High-fidelity rendering on shared computational resources

The generation of high-fidelity imagery is a computationally expensive process and parallel computing has been traditionally employed to alleviate this cost. However, traditional parallel rendering has been restricted to expensive shared memory or dedicated distributed processors. In contrast, parallel computing on shared resources such as a computational or a desktop grid, offers a low cost alternative. But, the prevalent rendering systems are currently incapable of seamlessly handling such shared resources as they suffer from high latencies, restricted bandwidth and volatility. A conventional approach of rescheduling failed jobs in a volatile environment inhibits performance by using redundant computations. Instead, clever task subdivision along with image reconstruction techniques provides an unrestrictive fault-tolerance mechanism, which is highly suitable for high-fidelity rendering. This thesis presents novel fault-tolerant parallel rendering algorithms for effectively tapping the enormous inexpensive computational power provided by shared resources. A first of its kind system for fully dynamic high-fidelity interactive rendering on idle resources is presented which is key for providing an immediate feedback to the changes made by a user. The system achieves interactivity by monitoring and adapting computations according to run-time variations in the computational power and employs a spatio-temporal image reconstruction technique for enhancing the visual fidelity. Furthermore, algorithms described for time-constrained offline rendering of still images and animation sequences, make it possible to deliver the results in a user-defined limit. These novel methods enable the employment of variable resources in deadline-driven environments

Microsoft Word - 07

ABSTRACT Crude extracts of Pterocarpus santalinus extracted with Petroleum ether, methanol, n-butanol, chloroform and ethanol were tested for antibacterial activity against 8 isolates viz. Staphylococcus aureus, Streptococcus mutans, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, C. glabrata, C. parapsilosis and C. tropicalis known to cause oral infections. Zone of inhibition produced by different extracts against the selected strains was measured and compared with standard antibiotic Ciprofloxacin (1%) and Fluconazole (1%). The antibacterial sensitivity of crude extracts were tested by the disc diffusion test, and results showed that ethanol extracts and methanol extracts had average inhibition zones ranged from 18-23 and 10-16 mm in diameter, respectively while no activity was observed for other extracts. Minimum Inhibitory Concentrations (MIC) of ethanol extract was evaluated against these oral pathogens ranged from 4-8 mg/ml while MIC of methanol extract ranged from 6-10 mg/ml. The synergy testing of ethanol extract was also carried out with known antimicrobial agents using agar well diffusion method. The results of conducted experiments using agar well diffusion demonstrated synergistic effects between antibiotics and plant extracts with significant reduction in the MICs of the test antibiotics against these strains. This study suggests the possibility of concurrent use of these antimicrobial drugs and extracts in combination in treating infections caused by these oral pathogens

Maintaining frame rate perception in interactive environments by exploiting audio-visual cross-modal interaction

The entertainment industry, primarily the video games industry, continues to dictate the development and performance requirements of graphics hardware and computer graphics algorithms. However, despite the enormous progress in the last few years, it is still not possible to achieve some of industry's demands, in particular high-fidelity rendering of complex scenes in real-time, on a single desktop machine. A realisation that sound/music and other senses are important to entertainment led to an investigation of alternative methods, such as cross-modal interaction in order to try and achieve the goal of "realism in real-time". In this paper we investigate the cross-modal interaction between vision and audition for reducing the amount of computation required to compute visuals by introducing movement related sound effects. Additionally, we look at the effect of camera movement speed on temporal visual perception. Our results indicate that slow animations are perceived as smoother than fast animations. Furthermore, introducing the sound effect of footsteps to walking animations further increased the animation smoothness perception. This has the consequence that for certain conditions, the number of frames that need to be rendered each second can be reduced, saving valuable computation time, without the viewer being aware of this reduction. The results presented are another step towards the full understanding of the auditory-visual cross-modal interaction and its importance for helping achieve "realism int real-time"

Exploiting audio-visual cross-modal interaction to reduce computational requirements in interactive environments

The quality of real-time computer graphics has progressed enormously in the last decade due to the rapid development in graphics hardware and its utilisation of new algorithms and techniques. The computer games industry, with its substantial software and hardware requirements, has been at the forefront in pushing these developments. Despite all the advances, there is still a demand for even more computational resources. For example, sound effects are an integral part of most computer games. This paper presents a method for reducing the amount of effort required to compute the computer graphics aspects of a game by exploiting movement related sound effects. We conducted a detailed psychophysical experiment investigating how camera movement speed and the sounds affect the perceived smoothness of an animation. The results show that walking (slow) animations were perceived as smoother than running (fast) animations. We also found that the addition of sound effects, such as footsteps, to a walking/running animation affects the animation smoothness perception. This entails that for certain conditions the number of frames that need to be rendered each second can be reduced saving valuable computation time. Our approach will enable the computed frame rate to be decreased, and thus the computational requirements to be lowered, without any perceivable visual loss of qualit

Time-constrained high-fidelity rendering on local desktop grids

Parallel computing has been frequently used for reducing the rendering time of high-fidelity images, since the generation of such images has a high computational cost. Numerous algorithms have been proposed for parallel rendering but they primarily focus on utilising shared memory machines or dedicated distributed clusters. A local desktop grid, composed of arbitrary computational resources connected to a network such as those in a lab or an enterprise, provides an inexpensive alternative to dedicated clusters. The computational power offered by such a desktop grid is time-variant as the resources are not dedicated. This paper presents fault-tolerant algorithms for rendering high-fidelity images on a desktop grid within a given time-constraint. Due to the dynamic nature of resources, the task assignment does not rely on subdividing the image into tiles. Instead, a progressive approach is used that encompasses aspects of the entire image for each task and ensures that the time-constraints are met. Traditional reconstruction techniques are used to calculate the missing data. This approach is designed to avoid redundancy to maintain time-constraints. As a further enhancement, the algorithm decomposes the computation into components representing different tasks to achieve better visual quality considering the time-constraint and variable resources. This paper illustrates how the component-based approach maintains a better visual fidelity considering a given time-constraint while making use of volatile computational resources

High-fidelity interactive rendering on desktop grids

Traditionally, high computational costs have restricted high-fidelity interactive rendering to expensive shared-memory or dedicated distributed processors. Desktop grids offer a low-cost alternative by combining arbitrary computational resources connected to a network, such as the resources in a laboratory or an office. However, the prevalent interactive rendering algorithms can't seamlessly handle the variable computational power offered by a desktop grid's nondedicated resources. A proposed fault-tolerant algorithm renders high-fidelity images at an interactive rate that can handle variable resources. A conventional approach of rescheduling failed jobs in a volatile environment would inhibit performance when rendering at interactive rates because the time margins are small. Instead, this method uses quasi-random sampling along with image reconstruction. This video shows examples of scenes rendered on a desktop grid

Phenyl Dihydrouracil: An Alternative Cereblon Binder for PROTAC Design

Thalidomide and its analogues are frequently used in PROTAC design. However, they are known to be inherently unstable, undergoing hydrolysis even in commonly utilized cell culture media. We recently reported that phenyl glutarimide (PG)-based PROTACs displayed improved chemical stability and, consequently, improved protein degradation efficacy and cellular potency. Our optimization efforts, aiming to further improve the chemical stability and eliminate the racemization-prone chiral center in PG, led us to the development of phenyl dihydrouracil (PD)-based PROTACs. Here we describe the design and synthesis of LCK-directing PD-PROTACs and compare their physicochemical and pharmacological properties to those of the corresponding IMiD and PG analogues

Selective CK1a Degraders Exert Antiproliferative Activity Against a Broad Range of Human Cancer Cell Lines

CK1a degradatio