Research on a non-destructive fluidic storage control device

Fluidic memory device with associated fluidic alpha numerical displa

Weighted p-bits for FPGA implementation of probabilistic circuits

Probabilistic spin logic (PSL) is a recently proposed computing paradigm based on unstable stochastic units called probabilistic bits (p-bits) that can be correlated to form probabilistic circuits (p-circuits). These p-circuits can be used to solve problems of optimization, inference and also to implement precise Boolean functions in an "inverted" mode, where a given Boolean circuit can operate in reverse to find the input combinations that are consistent with a given output. In this paper we present a scalable FPGA implementation of such invertible p-circuits. We implement a "weighted" p-bit that combines stochastic units with localized memory structures. We also present a generalized tile of weighted p-bits to which a large class of problems beyond invertible Boolean logic can be mapped, and how invertibility can be applied to interesting problems such as the NP-complete Subset Sum Problem by solving a small instance of this problem in hardware

MADX: Memristors-As-Drivers for Crossbar logic

Memristors have the potential to not only replace conventional memory, but also to open up new design possibilities because they store 1s and 0s as resistances rather than voltages. A memristor architecture that has attracted interest for its versatility and ease of integration with existing CMOS technologies is the crossbar array. In this paper, I modify the MAD scheme to create the MADX scheme for performing basic logic operations within a crossbar array. Then, I compare this scheme against two of the most well-known schemes, MAGIC and IMPLY. In the case study of a full-adder, both a one-bit and an 8-bit version, the MADX scheme achieves lower latency and substantially lower area requirements than both MAGIC and IMPLY. This is because it is more flexible about storing output values than either, does not destroy input values unlike IMPLY, and has more basic operations. In particular, it has XOR, which neither IMPLY nor MAGIC have and is useful for additionPlan II Honors Progra

New developments in the theory of Groebner bases and applications to formal verification

We present foundational work on standard bases over rings and on Boolean Groebner bases in the framework of Boolean functions. The research was motivated by our collaboration with electrical engineers and computer scientists on problems arising from formal verification of digital circuits. In fact, algebraic modelling of formal verification problems is developed on the word-level as well as on the bit-level. The word-level model leads to Groebner basis in the polynomial ring over Z/2n while the bit-level model leads to Boolean Groebner bases. In addition to the theoretical foundations of both approaches, the algorithms have been implemented. Using these implementations we show that special data structures and the exploitation of symmetries make Groebner bases competitive to state-of-the-art tools from formal verification but having the advantage of being systematic and more flexible.Comment: 44 pages, 8 figures, submitted to the Special Issue of the Journal of Pure and Applied Algebr

Adaptive voting computer system

A computer system is reported that uses adaptive voting to tolerate failures and operates in a fail-operational, fail-safe manner. Each of four computers is individually connected to one of four external input/output (I/O) busses which interface with external subsystems. Each computer is connected to receive input data and commands from the other three computers and to furnish output data commands to the other three computers. An adaptive control apparatus including a voter-comparator-switch (VCS) is provided for each computer to receive signals from each of the computers and permits adaptive voting among the computers to permit the fail-operational, fail-safe operation