4 research outputs found

    Machine-learning-based side-channel evaluation of elliptic-curve cryptographic FPGA processor.

    Get PDF
    Security of embedded systems is the need of the hour. A mathematically secure algorithm runs on a cryptographic chip on these systems, but secret private data can be at risk due to side-channel leakage information. This research focuses on retrieving secret-key information, by performing machine-learning-based analysis on leaked power-consumption signals, from Field Programmable Gate Array (FPGA) implementation of the elliptic-curve algorithm captured from a Kintex-7 FPGA chip while the elliptic-curve cryptography (ECC) algorithm is running on it. This paper formalizes the methodology for preparing an input dataset for further analysis using machine-learning-based techniques to classify the secret-key bits. Research results reveal how pre-processing filters improve the classification accuracy in certain cases, and show how various signal properties can provide accurate secret classification with a smaller feature dataset. The results further show the parameter tuning and the amount of time required for building the machine-learning modelsUniversity of Derb

    Development of shape memory polymer-based deployable solar reflector by 4-D printing technology

    No full text
    4-D printing refers to the ability for a 3-D printed material to change its shape and properties once activated by external variants such as heat or moisture. The 3D model shape is initially printed by a 3D printer where printing of any free form shape is possible and for additive manufacturing purposes, using material that possesses the shape memory effect. The final prototype, which is a satellite reflector, is to be printed and tested. In this project, the material, Fullcure 720 is tested throughout the whole project. Test specimens are printed in order to investigate different parameters such as the tensile stress, maximum recoverable tensile strain and response rate of the material. Experiments on the specimens are also conducted to determine the properties of the material and shape memory effects. After testing, the desired properties are then incorporated to the design of the reflector. Several designs are considered before the final prototype is chosen and printed. Two prototypes, one with black coating, and one without any coating, are tested to determine its recovery rate.Bachelor of Engineering (Mechanical Engineering

    Prophylactic biological mesh reinforcement versus standard closure of stoma site (ROCSS): a multicentre, randomised controlled trial

    No full text
    Background: Closure of an abdominal stoma, a common elective operation, is associated with frequent complications; one of the commonest and impactful is incisional hernia formation. We aimed to investigate whether biological mesh (collagen tissue matrix) can safely reduce the incidence of incisional hernias at the stoma closure site. Methods: In this randomised controlled trial (ROCSS) done in 37 hospitals across three European countries (35 UK, one Denmark, one Netherlands), patients aged 18 years or older undergoing elective ileostomy or colostomy closure were randomly assigned using a computer-based algorithm in a 1:1 ratio to either biological mesh reinforcement or closure with sutures alone (control). Training in the novel technique was standardised across hospitals. Patients and outcome assessors were masked to treatment allocation. The primary outcome measure was occurrence of clinically detectable hernia 2 years after randomisation (intention to treat). A sample size of 790 patients was required to identify a 40% reduction (25% to 15%), with 90% power (15% drop-out rate). This study is registered with ClinicalTrials.gov, NCT02238964. Findings: Between Nov 28, 2012, and Nov 11, 2015, of 1286 screened patients, 790 were randomly assigned. 394 (50%) patients were randomly assigned to mesh closure and 396 (50%) to standard closure. In the mesh group, 373 (95%) of 394 patients successfully received mesh and in the control group, three patients received mesh. The clinically detectable hernia rate, the primary outcome, at 2 years was 12% (39 of 323) in the mesh group and 20% (64 of 327) in the control group (adjusted relative risk [RR] 0·62, 95% CI 0·43–0·90; p=0·012). In 455 patients for whom 1 year postoperative CT scans were available, there was a lower radiologically defined hernia rate in mesh versus control groups (20 [9%] of 229 vs 47 [21%] of 226, adjusted RR 0·42, 95% CI 0·26–0·69; p<0·001). There was also a reduction in symptomatic hernia (16%, 52 of 329 vs 19%, 64 of 331; adjusted relative risk 0·83, 0·60–1·16; p=0·29) and surgical reintervention (12%, 42 of 344 vs 16%, 54 of 346: adjusted relative risk 0·78, 0·54–1·13; p=0·19) at 2 years, but this result did not reach statistical significance. No significant differences were seen in wound infection rate, seroma rate, quality of life, pain scores, or serious adverse events. Interpretation: Reinforcement of the abdominal wall with a biological mesh at the time of stoma closure reduced clinically detectable incisional hernia within 24 months of surgery and with an acceptable safety profile. The results of this study support the use of biological mesh in stoma closure site reinforcement to reduce the early formation of incisional hernias. Funding: National Institute for Health Research Research for Patient Benefit and Allergan
    corecore