7 research outputs found

    Hardware IP Classification through Weighted Characteristics

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    Today’s business model for hardware designs frequently incorporates third-party Intellectual Property (IP) due to the many benefits it can bring to a company. For instance, outsourcing certain components of an overall design can reduce time-to-market by allowing each party to specialize and perfect a specific part of the overall design. However, allowing third-party involvement also increases the possibility of malicious attacks, such as hardware Trojan insertion. Trojan insertion is a particularly dangerous security threat because testing the functionality of an IP can often leave the Trojan undetected. Therefore, this thesis work provides an improvement on a Trojan detection method known as Structural Checking which analyzes Register-Transfer Level (RTL) and gate-level soft IPs. Given an unknown IP, the Structural Checking tool will break down the design primary ports and internal signals into assets that fall into six characteristics. These characteristics organize how the IP is structured and provide information about the unknown IP’s overall function. The tool also provides a library of known designs referred to as the Golden Reference Library (GRL). All entries in the library are also broken down into the same six characteristics and are either known to be clean or known to have a Trojan inserted. An overall percent match for each library entry against the unknown IP is calculated by first computing a percent match within each characteristic. A weighted average of these percent matches makes up the final percentage. If the library entry with the best match is known to have a Trojan inserted, then the unknown design is likely to have a Trojan as well and vice versa. Due to the structural variability of soft IP designs, it is vital to provide the best possible weighting of the six characteristics to best match the unknown IP to the most similar library entry. This thesis work provides a statistical approach to finding the best weights to optimize the Structural Checking tool’s matching algorithm

    Changes in Intraocular Pressure with Use of Periocular Triamcinolone Cream

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    Purpose: To evaluate the effect of periocular topical triamcinolone cream on intraocular pressure. Methods: A retrospective chart review identified 57 patients, 114 eyes using triamcinolone cream (0.1%, 0.025%) with subsequent intraocular pressure (IOP) checks at three follow-up visits. Descriptive, univariate, and multivariate analyses were performed to assess effects of age, therapy duration, consecutive weeks on steroid, prescription strength, time of day, and method of measurement on IOP levels. Generalized Estimating Equations were used in regression models to account for correlation of eyes within subjects and across visits. Results: We identified 57 patients using triamcinolone cream for allergic or eczematous dermatitis of the eyelid. Prescription strengths were 0.025% or 0.1% and patients were followed for a median of 4.9 months. Measurements of IOP at baseline did not change as compared to all IOP measurements at follow-ups and did not change with steroid strength. The mean change in IOP at all follow-up visits was 0.07 mm Hg (95% confidence interval [CI]: –0.36, 0.50). After adjustment for the method of tonometer and the patient’s age, the mean change was 0.03 mm Hg (95% CI: –0.68, 0.73, P = 0.93). Prescription strength and consecutive weeks of therapy were not associated with IOP. Two patients experienced a significant elevation in IOP of >10 mm Hg, one through the concomitant consequences of systemic corticosteroids usage and the other through prolonged topical application. Conclusion: In patients taking periocular triamcinolone cream, there was no clinically meaningful change in mean IOP between baseline and follow-up visits, and IOP measurements were not related to variances in prescription strength or duration of therapy
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