GRAAL --- A Development Framework for Embedded Graphics Accelerators

This paper presents a versatile hardware/software cosimulation and co-design environment for embedded 3D graphics accelerators. The GRAphics AcceLerator design exploration framework (GRAAL) is an open system which offers a coherent development methodology based on an extensive library of SystemC RTL models of graphics pipeline components. GRAAL incorporates tools to assist in the visual debugging of the graphics algorithms implemented in hardware, and to estimate the performance in terms of throughput, power consumption, and area

Hardware Algorithms For Tile-Based Real-Time Rendering

In this dissertation, we present the GRAphics AcceLerator (GRAAL) framework for developing embedded tile-based rasterization hardware for mobile devices, meant to accelerate real-time 3-D graphics (OpenGL compliant) applications. The goal of the framework is a low-cost, low-power, high-performance design that delivers good image quality. We focus on several key problem areas in tile-based rasterization, such as: rasterization and triangle traversal, antialiasing, and geometrical primitive list sorting. We present an original triangle traversal hardware algorithm implementation, composed of a systolic primitive scan-conversion subsystem and a logic-enhanced memory subsystem, able to deliver 4 pixel positions per clock cycle in a very advantageous spatial pattern, exploited to reduce the power consumption and increase the throughput, to the pixel processing pipelines for rasterization. Area-sampling antialiasing is achieved with a pixel-coverage mask generation algorithm that reduces the mask storage costs by exploiting the quadrant symmetry property when deriving on the fly, via computationally inexpensive operations, the required coverage masks. The costs are reduced by an order of magnitude and the image quality, i.e., coverage mask accuracy, almost doubles when compared to prior state-of-the-art implementations. At the front end of the rasterization process, as the host processor needs to be able to process different other system tasks in a system-on-chip embedded architecture, we propose a novel and efficient hardware primitive list sorting algorithm that lowers on the one hand the effort of the host processor required to generate the primitive tiling lists and reduces on the other hand the external memory traffic. For an implementation footprint similar to an 8KB SRAM memory macro, the number of the instructions on the host processor for tiling list generation was lowered by 4–9x and the memory cost by 3–6x, for our embedded benchmark suite GraalBench, when compared to the software driver implementation alone. Our estimations indicate that the GRAAL design, clocked at a frequency of 200MHz, can sustain a rendering and fill rate of 2.4 million triangles/s and 460 million pixels/s for typical 3-D graphics scenes.Computer EngineeringElectrical Engineering, Mathematics and Computer Scienc

3D Graphics Tile-Based Systolic Scan-Conversion

Abstract — A 3D graphics systolic scan-conversion unit is presented that solves existing problems associated with tile-based hardware rasterization algorithms. In our proposal no searching overhead is needed to find the first hit position inside the primitives. Furthermore “ghost ” primitives are handled efficiently with a small constant delay irrespective of the primitive size. Finally, hit positions (communicated in a spatial pattern to increase texture cache hit ratios) can always be mapped to different memory banks in the Z-buffer or color-buffer breaking the “readmodify-write” dependency associated with depth test and color blending. Hardware synthesis in a commercial 0.18µm process technology has indicated that the hardware implementation requires an area of 269964µm 2, it can be clocked at a frequency of 200MHz and consumes 33mW. The rendering and the fill rate achieved are 2.4 million triangles/s and460 million pixels/s for graphics scenes with typical average triangle area of 160 pixels. I

GRAAL: A framework for low-power 3D graphics accelerators

The GRAphics AcceLerator (GRAAL) design-exploration framework is an open system that offers a coherent development methodology for hardware/software cosimulation and codesign of embedded 3D graphics accelerators. GRAAL incorporates tools to help visually debug graphics algorithms implemented in hardware and to estimate performance in terms of throughput, power consumption, and area.Microelectronics & Computer EngineeringElectrical Engineering, Mathematics and Computer Scienc

Ferric carboxymaltose for iron deficiency at discharge after acute heart failure: a multicentre, double-blind, randomised, controlled trial

Background: Intravenous ferric carboxymaltose has been shown to improve symptoms and quality of life in patients with chronic heart failure and iron deficiency. We aimed to evaluate the effect of ferric carboxymaltose, compared with placebo, on outcomes in patients who were stabilised after an episode of acute heart failure. Methods: AFFIRM-AHF was a multicentre, double-blind, randomised trial done at 121 sites in Europe, South America, and Singapore. Eligible patients were aged 18 years or older, were hospitalised for acute heart failure with concomitant iron deficiency (defined as ferritin <100 μg/L, or 100–299 μg/L with transferrin saturation <20%), and had a left ventricular ejection fraction of less than 50%. Before hospital discharge, participants were randomly assigned (1:1) to receive intravenous ferric carboxymaltose or placebo for up to 24 weeks, dosed according to the extent of iron deficiency. To maintain masking of patients and study personnel, treatments were administered in black syringes by personnel not involved in any study assessments. The primary outcome was a composite of total hospitalisations for heart failure and cardiovascular death up to 52 weeks after randomisation, analysed in all patients who received at least one dose of study treatment and had at least one post-randomisation data point. Secondary outcomes were the composite of total cardiovascular hospitalisations and cardiovascular death; cardiovascular death; total heart failure hospitalisations; time to first heart failure hospitalisation or cardiovascular death; and days lost due to heart failure hospitalisations or cardiovascular death, all evaluated up to 52 weeks after randomisation. Safety was assessed in all patients for whom study treatment was started. A pre-COVID-19 sensitivity analysis on the primary and secondary outcomes was prespecified. This study is registered with ClinicalTrials.gov, NCT02937454, and has now been completed. Findings: Between March 21, 2017, and July 30, 2019, 1525 patients were screened, of whom 1132 patients were randomly assigned to study groups. Study treatment was started in 1110 patients, and 1108 (558 in the carboxymaltose group and 550 in the placebo group) had at least one post-randomisation value. 293 primary events (57·2 per 100 patient-years) occurred in the ferric carboxymaltose group and 372 (72·5 per 100 patient-years) occurred in the placebo group (rate ratio [RR] 0·79, 95% CI 0·62–1·01, p=0·059). 370 total cardiovascular hospitalisations and cardiovascular deaths occurred in the ferric carboxymaltose group and 451 occurred in the placebo group (RR 0·80, 95% CI 0·64–1·00, p=0·050). There was no difference in cardiovascular death between the two groups (77 [14%] of 558 in the ferric carboxymaltose group vs 78 [14%] in the placebo group; hazard ratio [HR] 0·96, 95% CI 0·70–1·32, p=0·81). 217 total heart failure hospitalisations occurred in the ferric carboxymaltose group and 294 occurred in the placebo group (RR 0·74; 95% CI 0·58–0·94, p=0·013). The composite of first heart failure hospitalisation or cardiovascular death occurred in 181 (32%) patients in the ferric carboxymaltose group and 209 (38%) in the placebo group (HR 0·80, 95% CI 0·66–0·98, p=0·030). Fewer days were lost due to heart failure hospitalisations and cardiovascular death for patients assigned to ferric carboxymaltose compared with placebo (369 days per 100 patient-years vs 548 days per 100 patient-years; RR 0·67, 95% CI 0·47–0·97, p=0·035). Serious adverse events occurred in 250 (45%) of 559 patients in the ferric carboxymaltose group and 282 (51%) of 551 patients in the placebo group. Interpretation: In patients with iron deficiency, a left ventricular ejection fraction of less than 50%, and who were stabilised after an episode of acute heart failure, treatment with ferric carboxymaltose was safe and reduced the risk of heart failure hospitalisations, with no apparent effect on the risk of cardiovascular death. Funding: Vifor Pharma

Edoxaban versus warfarin in patients with atrial fibrillation

Contains fulltext : 125374.pdf (publisher's version ) (Open Access)BACKGROUND: Edoxaban is a direct oral factor Xa inhibitor with proven antithrombotic effects. The long-term efficacy and safety of edoxaban as compared with warfarin in patients with atrial fibrillation is not known. METHODS: We conducted a randomized, double-blind, double-dummy trial comparing two once-daily regimens of edoxaban with warfarin in 21,105 patients with moderate-to-high-risk atrial fibrillation (median follow-up, 2.8 years). The primary efficacy end point was stroke or systemic embolism. Each edoxaban regimen was tested for noninferiority to warfarin during the treatment period. The principal safety end point was major bleeding. RESULTS: The annualized rate of the primary end point during treatment was 1.50% with warfarin (median time in the therapeutic range, 68.4%), as compared with 1.18% with high-dose edoxaban (hazard ratio, 0.79; 97.5% confidence interval [CI], 0.63 to 0.99; P<0.001 for noninferiority) and 1.61% with low-dose edoxaban (hazard ratio, 1.07; 97.5% CI, 0.87 to 1.31; P=0.005 for noninferiority). In the intention-to-treat analysis, there was a trend favoring high-dose edoxaban versus warfarin (hazard ratio, 0.87; 97.5% CI, 0.73 to 1.04; P=0.08) and an unfavorable trend with low-dose edoxaban versus warfarin (hazard ratio, 1.13; 97.5% CI, 0.96 to 1.34; P=0.10). The annualized rate of major bleeding was 3.43% with warfarin versus 2.75% with high-dose edoxaban (hazard ratio, 0.80; 95% CI, 0.71 to 0.91; P<0.001) and 1.61% with low-dose edoxaban (hazard ratio, 0.47; 95% CI, 0.41 to 0.55; P<0.001). The corresponding annualized rates of death from cardiovascular causes were 3.17% versus 2.74% (hazard ratio, 0.86; 95% CI, 0.77 to 0.97; P=0.01), and 2.71% (hazard ratio, 0.85; 95% CI, 0.76 to 0.96; P=0.008), and the corresponding rates of the key secondary end point (a composite of stroke, systemic embolism, or death from cardiovascular causes) were 4.43% versus 3.85% (hazard ratio, 0.87; 95% CI, 0.78 to 0.96; P=0.005), and 4.23% (hazard ratio, 0.95; 95% CI, 0.86 to 1.05; P=0.32). CONCLUSIONS: Both once-daily regimens of edoxaban were noninferior to warfarin with respect to the prevention of stroke or systemic embolism and were associated with significantly lower rates of bleeding and death from cardiovascular causes. (Funded by Daiichi Sankyo Pharma Development; ENGAGE AF-TIMI 48 ClinicalTrials.gov number, NCT00781391.)