Physical unclonable functions (PUFs) are the circuits that extract a number of unique chip signatures determined by random physical variations from fabrication. Since they are able to securely store and generate secret keys, PUFs allow to bootstrap the hardware-based implementation of an information security. This manuscript proposes a novel ternary content addressable memory based PUF (TCAM-PUF) for secure embedded systems. The PUF responses are simulated under various conditions, which are start-up values of TCAM cells. The results show that the proposed TCAM-PUF provides higher reliability and uniqueness than SRAM-PUF, which is one of the widely-used memory cell-based weak PUFs. According to our simulation, our TCAM-PUF provides an inter-chip and intra-chip hamming distance of 49.5% and 3.5% (on average), respectively and uniformity of 49.8% (on average).

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In this paper, we propose a new variable latency L1 data cache architecture for multi-core processors. Our proposed architecture extends the traditional variable latency cache to be geared toward the multi-core processors. We added a specialized data structure for recording the latency of the L1 data cache. Depending on the added latency to the L1 data cache, the value stored to the data structure is determined. It also tracks the remaining cycles of the L1 data cache which notifies data arrival to the reservation station in the core. As in the variable latency cache of the single-core architecture, our proposed architecture flexibly extends the cache access cycles considering process variation. The proposed cache architecture can reduce yield losses incurred by L1 cache access time failures to nearly 0%. Moreover, we quantitatively evaluate performance, power, energy consumption, power-delay product, and energy-delay product when increasing the number of cache access cycles.

In this study, we investigate whether and to what extent country‐level board reforms affect audit pricing decisions. We find audit fees are positively associated with board reforms. An increase in audit fees is more pronounced for firms that switched up to Big N auditors following board reforms. After board reforms, firms are less likely to issue restatements, and both analyst forecast accuracy and management forecast frequency increase, indicating improved audit quality and information transparency in the postreform period. Moreover, the positive relation between board reforms and audit fees is more evident for firms in countries that lack institutional governance mechanisms, captured by emerging capital markets, high political risk, weak governmental enforcement actions and low corporate governance quality. Overall, our findings broadly support the view that audit fees increase upon demand for better audit quality.

Using data for 54 countries from 1989 to 2017, we empirically show that democratic development has a significant negative effect on audit fees. We find that a one standard deviation increase in democracy decreaseσ audit fees by 19.9% on average. Moreover, we find a big N premium decreases with democratization, and foreign auditors charge a higher premium to compensate information asymmetry against clients. We employ instrumental variables and unexpected regime changes as additional identification strategies. Overall, we show that democratization improves confidence in capital markets and reduces client-specific risks, which decreases audit fees.