random number generation
Field-programmable dynamics in a soft magnetic actuator enabling true random number generation and reservoir computing
Oliveros-Mata, Eduardo Sergio, Pylypovskyi, Oleksandr V., Raimondo, Eleonora, Illing, Rico, Zabila, Yevhen, Guo, Lin, Mu, Guannan, López, Mónica Navarro, Wang, Xu, Tzortzinis, Georgios, Filippatos, Angelos, Bermúdez, Gilbert Santiago Cañón, Garescì, Francesca, Finocchio, Giovanni, Makarov, Denys
Department of Mathematical and Computer Sciences, Physical Sciences and Earth Sciences, University of Messina, 8166 Messina, Italy Complex and even chaotic dynamics, though prevalent in many natural and engineered systems, has been largely avoided in the design of electromechanical systems due to concerns about wear and controlability. Here, we demonstrate that complex dynamics might be particularly advantageous in soft robotics, offering new functionalities beyond motion not easily achievable with traditional actuation methods. We designed and realized resilient magnetic soft actuators capable of operating in a tunable dynamic regime for tens of thousands cycles without fatigue. We experimentally demonstrated the application of these actuators for true random number generation and stochastic computing. These findings show that exploring the complex dynamics in soft robotics would extend the application scenarios in soft computing, human-robot interaction and collaborative robots as we demonstrate with biomimetic blinking and randomized voice modulation. A large number of mechanical systems, including simple ones such as the double pendulum, exhibit dynamics characterized by deterministic periodic and chaotic responses depending on the excitation frequency f and amplitude A of the applied force [1]. Mechanical systems with a tendency to chaotisation demonstrate multiple resonances and various transitions to chaos [2]. Today, the concept of complexity and, especially, deterministic chaos that refers to systems without stochastic fluctuations jet losing stability of phase space trajectories is explored for a variety of directions [3] even including biological systems [4] or optics [5]. In particular, chaos is a fundamental aspect of electromechanical systems and is broadly explored in motion planning for mobile rigid robots, fluid mixing, and improving energy harvesting, as well as in mechanisms used in washing machines, dishwashers, and air conditioners [6]. Although the analysis of traditional robotics and mechanisms has revealed inherent chaotic dynamics [7], chaos can also be intentionally generated through nonlinear feedback [6] to achieve specific functionalities. In contrast to rigid mechanisms, soft actuators can facilitate transition into complex dynamics without the need for dedicated feedback algorithms. Mechanically soft actuators do not possess any rigid components in their embodiment rendering them ideally suited to explore complex and even chaotic dynamics which is typically observed at higher frequencies (Supplementary Tables 1 and 2). The inherent nonlinear oscillations emerging in soft actuators for specific parameter values [8, 9] can be applied for secure, biomimetic, and soft computing applications.
Base Models Beat Aligned Models at Randomness and Creativity
West, Peter, Potts, Christopher
Alignment has quickly become a default ingredient in LLM development, with techniques such as reinforcement learning from human feedback making models act safely, follow instructions, and perform ever-better on complex tasks. While these techniques are certainly useful, we propose that they should not be universally applied and demonstrate a range of tasks on which base language models consistently outperform their popular aligned forms. Particularly, we study tasks that require unpredictable outputs, such as random number generation, mixed strategy games (rock-paper-scissors and hide-and-seek), and creative writing. In each case, aligned models tend towards narrow behaviors that result in distinct disadvantages, for instance, preferring to generate "7" over other uniformly random numbers, becoming almost fully predictable in some game states, or prioritizing pleasant writing over creative originality. Across models tested, better performance on common benchmarks tends to correlate with worse performance on our tasks, suggesting an effective trade-off in the required capabilities.
Energy-Efficient Sampling Using Stochastic Magnetic Tunnel Junctions
Alder, Nicolas, Kajale, Shivam Nitin, Tunsiricharoengul, Milin, Sarkar, Deblina, Herbrich, Ralf
We introduce an energy-efficient algorithm for uniform Float16 sampling, utilizing a roomtemperature stochastic magnetic tunnel junction device to generate truly random floating-point numbers. By avoiding expensive symbolic computation and mapping physical phenomena directly to the statistical properties of the floating-point format and uniform distribution, our approach achieves a higher level of energy efficiency than the state-of-the-art Mersenne-Twister algorithm by a minimum factor of 9721 and an improvement factor of 5649 compared to the more energy-efficient PCG algorithm. Building on this sampling technique and hardware framework, we decompose arbitrary distributions into many non-overlapping approximative uniform distributions along with convolution and prior-likelihood operations, which allows us to sample from any 1D distribution without closed-form solutions. We provide measurements of the potential accumulated approximation errors, demonstrating the effectiveness of our method. This not only increases the cost of products, but also presents obstacles in addressing climate change. Traditional AI methods like deep learning lack the ability to quantify uncertainties, which is crucial to address issues such as hallucinations or ensuring safety in critical tasks. Probabilistic machine learning, while providing a theoretical framework for achieving muchneeded uncertainty quantification, also suffers from high energy consumption and is unviable on a truly large scale due to insufficient computational resources (Izmailov et al., 2021). At the heart of probabilistic machine learning and Bayesian inference is Markov Chain Monte Carlo (MCMC) sampling (Kass et al., 1998; Murphy, 2012; Hoffman & Gelman, 2014). Although effective in generating samples from complex distributions, MCMC is known for its substantial computational and energy requirements, making it unsuitable for large-scale deployment for applications such as Bayesian neural networks (Izmailov et al., 2021). In general, random number generation is an expensive task that is required in many machine learning algorithms. To address these challenges, this paper proposes a novel hardware framework aimed at improving energy efficiency, in particular tailored for probabilistic machine learning methods. Our framework builds on uniform floating-point format sampling utilizing stochastically switching magnetic tunnel junction (s-MTJ) devices as a foundation, achieving significant gains in both computational resources and energy consumption compared to current pseudorandom number generators. In contrast to existing generators, this device-focused strategy not only enhances sampling efficiency but also incorporates genuine randomness originating from the thermal noise in our devices.
Research Papers about the developments in the Finite State Automation
Abstract: Graph-based neural network models are producing strong results in a number of domains, in part because graphs provide flexibility to encode domain knowledge in the form of relational structure (edges) between nodes in the graph. In practice, edges are used both to represent intrinsic structure (e.g., abstract syntax trees of programs) and more abstract relations that aid reasoning for a downstream task (e.g., results of relevant program analyses). In this work, we study the problem of learning to derive abstract relations from the intrinsic graph structure. Motivated by their power in program analyses, we consider relations defined by paths on the base graph accepted by a finite-state automaton. We show how to learn these relations end-to-end by relaxing the problem into learning finite-state automata policies on a graph-based POMDP and then training these policies using implicit differentiation.
Impact of Random Number Generation on Parallel Genetic Algorithms
Cicirello, Vincent A. (Stockton University)
In this paper, we present a parallel genetic algorithm (pGA) with adaptive control parameters and permutation representation for weighted tardiness scheduling with sequence-dependent setups, an NP-Hard problem. This pGA provides a linear to slightly superlinear speedup relative to its sequential counterpart. As part of our research, we explore the effects of different random number generation algorithms on the runtimes of both sequential and parallel GAs. GAs and other forms of evolutionary computation rely so heavily on random number generation that our results show that we can obtain a 20% increase in the speed of a pGA, and an over 25% increase in the speed of a sequential GA, simply by careful choice of random number generator---both the underlying generator as well as algorithms for specific number types such as Gaussian often needed for mutating real-valued genes.
When shuffling large arrays, how much time can be attributed to random number generation?
It is well known that contemporary computers don't like to randomly access data in an unpredictible manner in memory. However, not all forms of random accesses are equally harmful. Suppose that the array is large. Take an array made of 100 million elements. It far exceeds the CPU cache on the machines I own.
Trusted MCUs for IoT applications
As IoT technology continues to make our lives more comfortable through greater intelligence enabled by networking smart devices, it becomes increasingly important to protect the information stored and transmitted by these devices. Embedded MCUs are at the core of IoT-based products, and selecting the right MCU is key to meeting the present and future needs of your customers. An MCU designed for IoT applications needs to have sufficient processing capabilities, hardware-based security, and software algorithms to provide a safe and secure solution. Secure MCUs should offer multiple levels of security elements to support various security algorithms like Advanced Encryption Standard (AES), Data Encryption Standard (DES), and Secure Hash Algorithm (SHA). The MCU needs to provide a complete chain of security, secure boot process, hardware-based root of trust, true random number generation functionality in hardware, and user application code authentication, among other capabilities.