IA Scholar Query: Two-dimensional automata with rotated inputs.
https://scholar.archive.org/
Internet Archive Scholar query results feedeninfo@archive.orgThu, 04 Aug 2022 00:00:00 GMTfatcat-scholarhttps://scholar.archive.org/help1440Decomposing neural circuit function into information processing primitives
https://scholar.archive.org/work/jee5zuehivex7pfp6lks74wagq
ABSTRACTCognitive functions arise from the coordinated activity of neural populations distributed over large-scale brain networks. However, it is challenging to understand and measure how specific aspects of neural dynamics translate into operations of information processing, and, ultimately, cognitive functions. An obstacle is that simple circuit mechanisms–such as self-sustained or propagating activity and nonlinear summation of inputs–do not directly give rise to high-level functions. Nevertheless, they already implement simple transformations of the information carried by neural activity.Here, we propose that distinct neural circuit functions, such as stimulus representation, working memory, or selective attention stem from different combinations and types of low-level manipulations of information, or information processing primitives. To test this hypothesis, we combine approaches from information theory with computational simulations of canonical neural circuits involving one or more interacting brain regions that emulate well-defined cognitive functions. More specifically, we track the dynamics of information emergent from dynamic patterns of neural activity, using suitable quantitative metrics to detect where and when information is actively buffered ("active information storage"), transferred ("information transfer") or non-linearly merged ("information modification"), as possible modes of low-level processing. We find that neuronal subsets maintaining representations in working memory or performing attention-related gain modulation are signaled by their boosted involvement in operations of active information storage or information modification, respectively.Thus, information dynamics metrics, beyond detecting which network units participate in cognitive processing, also promise to specify how and when they do it, i.e., through which type of primitive computation, a capability that may be exploited for the parsing of actual experimental recordings.Nicole Voges, Johannes Hausmann, Andrea Brovelli, Demian Battagliawork_jee5zuehivex7pfp6lks74wagqThu, 04 Aug 2022 00:00:00 GMTLIPIcs, Volume 238, DNA 28, Complete Volume
https://scholar.archive.org/work/627o3xn4vbbgpdox5dwolgcuny
LIPIcs, Volume 238, DNA 28, Complete VolumeThomas E. Ouldridge, Shelley F. J. Wickhamwork_627o3xn4vbbgpdox5dwolgcunyThu, 04 Aug 2022 00:00:00 GMTEntropic associative memory for manuscript symbols
https://scholar.archive.org/work/a7ykh6v4gfebznwyh2qjq4trze
Manuscript symbols can be stored, recognized and retrieved from an entropic digital memory that is associative and distributed but yet declarative; memory retrieval is a constructive operation, memory cues to objects not contained in the memory are rejected directly without search, and memory operations can be performed through parallel computations. Manuscript symbols, both letters and numerals, are represented in Associative Memory Registers that have an associated entropy. The memory recognition operation obeys an entropy trade-off between precision and recall, and the entropy level impacts on the quality of the objects recovered through the memory retrieval operation. The present proposal is contrasted in several dimensions with neural networks models of associative memory. We discuss the operational characteristics of the entropic associative memory for retrieving objects with both complete and incomplete information, such as severe occlusions. The experiments reported in this paper add evidence on the potential of this framework for developing practical applications and computational models of natural memory.Rafael Morales, Noé Hernández, Ricardo Cruz, Victor D Cruz, Luis A Pinedawork_a7ykh6v4gfebznwyh2qjq4trzeThu, 04 Aug 2022 00:00:00 GMTOn Turedo Hierarchies and Intrinsic Universality
https://scholar.archive.org/work/3vxeg2fyejdnlp7mr4st2haq5u
This paper is about turedos, which are Turing machines whose head can move in the plane (or in a higher-dimensional space) but only in a self-avoiding way, by putting marks (letters) on visited positions and moving only to unmarked, therefore unvisited, positions. The turedo model has been introduced recently as a useful abstraction of oritatami systems, which where established a few years ago as a theoretical model of RNA co-transcriptional folding. The key parameter of turedos is their lookup radius: the distance up to which the head can look around in order to make its decision of where to move to and what mark to write. In this paper we study the hierarchy of turedos according to their lookup radius and the dimension of space using notions of simulation up to spatio-temporal rescaling (a standard approach in cellular automata or self-assembly systems). We establish that there is a rich interplay between the turedo parameters and the notion of simulation considered. We show in particular, for the most liberal simulations, the existence of 3D turedos of radius 1 that are intrinsically universal for all radii, but that this is impossible in dimension 2, where some radius 2 turedo are impossible to simulate at radius 1. Using stricter notions of simulation, intrinsic universality becomes impossible, even in dimension 3, and there is a strict radius hierarchy. Finally, when restricting to radius 1, universality is again possible in dimension 3, but not in dimension 2, where we show however that a radius 3 turedo can simulate all radius 1 turedos.Samuel Nalin, Guillaume Theyssier, Thomas E. Ouldridge, Shelley F. J. Wickhamwork_3vxeg2fyejdnlp7mr4st2haq5uThu, 04 Aug 2022 00:00:00 GMTMapping Research Topics in Software Testing: A Bibliometric Analysis
https://scholar.archive.org/work/e5bzjrtf7jd6famnf2wh5ynlau
The field of software testing is growing and rapidly-evolving. Aims: Based on keywords assigned to publications, we seek to identify predominant research topics and understand how they are connected and have evolved. Method: We apply co-word analysis to map the topology of testing research as a network where author-assigned keywords are connected by edges indicating co-occurrence in publications. Keywords are clustered based on edge density and frequency of connection. We examine the most popular keywords, summarize clusters into high-level research topics, examine how topics connect, and examine how the field is changing. Results: Testing research can be divided into 16 high-level topics and 18 subtopics. Creation guidance, automated test generation, evolution and maintenance, and test oracles have particularly strong connections to other topics, highlighting their multidisciplinary nature. Emerging keywords relate to web and mobile apps, machine learning, energy consumption, automated program repair and test generation, while emerging connections have formed between web apps, test oracles, and machine learning with many topics. Random and requirements-based testing show potential decline. Conclusions: Our observations, advice, and map data offer a deeper understanding of the field and inspiration regarding challenges and connections to explore.Alireza Salahirad, Gregory Gay, Ehsan Mohammadiwork_e5bzjrtf7jd6famnf2wh5ynlauWed, 03 Aug 2022 00:00:00 GMTMulti-Layer and Clustering-Based Security Implementation for an IoT Environment
https://scholar.archive.org/work/i56646qfrfevnaloyxwdcio344
IoT devices are having many constraints related to computation power and memory etc. Many existing cryptographic algorithms of security could not work with IoT devices because of these constraints. Since the sensors are used in large amount to collect the relevant data in an IoT environment, and different sensor devices transmit these data as useful information, the first thing needs to be secure is the identity of devices. The second most important thing is the reliable information transmission between a sensor node and a sink node. While designing the cryptographic method in the IoT environment, programmers need to keep in mind the power limitation of the constraint devices. Mutual authentication between devices and encryption-decryption of messages need some sort of secure key. In the proposed cryptographic environment, there will be a hierarchical clustering, and devices will get registered by the authentication center at the time they enter the cluster. The devices will get mutually authenticated before initiating any conversation and will have to follow the public key protocol.Deena Nath Gupta, Rajendra Kumarwork_i56646qfrfevnaloyxwdcio344Tue, 02 Aug 2022 00:00:00 GMTTechniques for combining fast local decoders with global decoders under circuit-level noise
https://scholar.archive.org/work/h7z4krmvibe6pkf4bjmndwpvfu
Implementing algorithms on a fault-tolerant quantum computer will require fast decoding throughput and latency times to prevent an exponential increase in buffer times between the applications of gates. In this work we begin by quantifying these requirements. We then introduce the construction of local neural network (NN) decoders using three-dimensional convolutions. These local decoders are adapted to circuit-level noise and can be applied to surface code volumes of arbitrary size. Their application removes errors arising from a certain number of faults, which serves to substantially reduce the syndrome density. Remaining errors can then be corrected by a global decoder, such as Blossom or Union Find, with their implementation significantly accelerated due to the reduced syndrome density. However, in the circuit-level setting, the corrections applied by the local decoder introduce many vertical pairs of highlighted vertices. To obtain a low syndrome density in the presence of vertical pairs, we consider a strategy of performing a syndrome collapse which removes many vertical pairs and reduces the size of the decoding graph used by the global decoder. We also consider a strategy of performing a vertical cleanup, which consists of removing all local vertical pairs prior to implementing the global decoder. Lastly, we estimate the cost of implementing our local decoders on Field Programmable Gate Arrays (FPGAs).Christopher Chamberland and Luis Goncalves and Prasahnt Sivarajah and Eric Peterson and Sebastian Grimbergwork_h7z4krmvibe6pkf4bjmndwpvfuTue, 02 Aug 2022 00:00:00 GMTUniversal anomalous fluctuations in charged single-file systems
https://scholar.archive.org/work/cimec6uoj5dobdna3cbyc6xami
Conventional classification of dynamical phenomena is based on universal hydrodynamic relaxation characterized by algebraic dynamical exponents and asymptotic scaling of the dynamical structure factor. This work uncovers a novel type of dynamical universality reflected in statistical properties of macroscopic fluctuating observables such as the transmitted charge. By considering a general class of one-dimensional single-file systems (meaning that particle crossings are prohibited) of interacting hardcore charged particles, we demonstrate that stringent dynamical constraints give rise to universal anomalous statistics of cumulative charge currents manifested both on the timescale characteristic of typical fluctuations and also in the rate function describing rare events. By computing the full counting statistics of net transferred charge between two extended subsystems, we establish a number of unorthodox dynamical properties in an analytic fashion. Most prominently, typical fluctuations in equilibrium are governed by a universal distribution that markedly deviates from the expected Gaussian statistics, whereas large fluctuations are described by an exotic large-deviation rate function featuring an exceptional triple critical point. Far from equilibrium, competition between dynamical phases leads to dynamical phase transitions of first and second order. Despite dynamical criticality, we find the large-deviation rate function of the joint particle-charge transfer obeys the fluctuation relation. Curiously, the univariate charge-current rate function experiences a spontaneous breaking of fluctuation symmetry upon varying the particle and charge densities in a nonequilibrium initial state. The rich phenomenology of the outlined dynamical universality is exemplified on an exactly solvable classical cellular automaton of charged hardcore particles.Žiga Krajnik, Johannes Schmidt, Vincent Pasquier, Tomaž Prosen, Enej Ilievskiwork_cimec6uoj5dobdna3cbyc6xamiTue, 02 Aug 2022 00:00:00 GMTPM-FSM: Policies Modulating Finite State Machine for Robust Quadrupedal Locomotion
https://scholar.archive.org/work/jq5e35yyejf57mes62b3s6wtpi
Deep reinforcement learning (deep RL) has emerged as an effective tool for developing controllers for legged robots. However, vanilla deep RL often requires a tremendous amount of training samples and is not feasible for achieving robust behaviors. Instead, researchers have investigated a novel policy architecture by incorporating human experts' knowledge, such as Policies Modulating Trajectory Generators (PMTG). This architecture builds a recurrent control loop by combining a parametric trajectory generator (TG) and a feedback policy network to achieve more robust behaviors. To take advantage of human experts' knowledge but eliminate time-consuming interactive teaching, researchers have investigated a novel architecture, Policies Modulating Trajectory Generators (PMTG), which builds a recurrent control loop by combining a parametric trajectory generator (TG) and a feedback policy network to achieve more robust behaviors using intuitive prior knowledge. In this work, we propose Policies Modulating Finite State Machine (PM-FSM) by replacing TGs with contact-aware finite state machines (FSM), which offer more flexible control of each leg. Compared with the TGs, FSMs offer high-level management on each leg motion generator and enable a flexible state arrangement, which makes the learned behavior less vulnerable to unseen perturbations or challenging terrains. This invention offers an explicit notion of contact events to the policy to negotiate unexpected perturbations. We demonstrated that the proposed architecture could achieve more robust behaviors in various scenarios, such as challenging terrains or external perturbations, on both simulated and real robots. The supplemental video can be found at: https://youtu.be/78cboMqTkJQ.Ren Liu, Nitish Sontakke, Sehoon Hawork_jq5e35yyejf57mes62b3s6wtpiMon, 01 Aug 2022 00:00:00 GMTJohn Horton Conway (1937–2020)
https://scholar.archive.org/work/atrm67fze5fjbb7qhm75morete
Alex Ryba, R T Curtis, Richard Borcherds, Manjul Bhargava, Dierk Schleicher, Jane Gilman, Aaron Siegel, Louis H. Kauffmanwork_atrm67fze5fjbb7qhm75moreteMon, 01 Aug 2022 00:00:00 GMTDistortion element in the automorphism group of a full shift
https://scholar.archive.org/work/rzg3vkkqjvegnhdeqvittrbf6y
We show that there is a distortion element in a finitely-generated subgroup G of the automorphism group of the full shift, namely an element of infinite order whose word norm grows polylogarithmically. As a corollary, we obtain a lower bound on the entropy dimension of any subshift containing a copy of G, and that a sofic shift's automorphism group contains a distortion element if and only if the sofic shift is uncountable. We obtain also that groups of Turing machines and the higher-dimensional Brin-Thompson groups mV admit distortion elements; in particular, 2V (unlike V) does not admit a proper action on a CAT(0) cube complex. The distortion element is essentially the SMART machine.Antonin Callard, Ville Salowork_rzg3vkkqjvegnhdeqvittrbf6yMon, 01 Aug 2022 00:00:00 GMTGenerative Design of Physical Objects using Modular Framework
https://scholar.archive.org/work/wbadsgor7zgmfpbsawnfngoffa
In recent years generative design techniques have become firmly established in numerous applied fields, especially in engineering. These methods are demonstrating intensive growth owing to promising outlook. However, existing approaches are limited by the specificity of problem under consideration. In addition, they do not provide desired flexibility. In this paper we formulate general approach to an arbitrary generative design problem and propose novel framework called GEFEST (Generative Evolution For Encoded STructure) on its basis. The developed approach is based on three general principles: sampling, estimation and optimization. This ensures the freedom of method adjustment for solution of particular generative design problem and therefore enables to construct the most suitable one. A series of experimental studies was conducted to confirm the effectiveness of the GEFEST framework. It involved synthetic and real-world cases (coastal engineering, microfluidics, thermodynamics and oil field planning). Flexible structure of the GEFEST makes it possible to obtain the results that surpassing baseline solutions.Nikita O. Starodubcev, Nikolay O. Nikitin, Konstantin G. Gavaza, Elizaveta A. Andronova, Denis O. Sidorenko, Anna V. Kalyuzhnayawork_wbadsgor7zgmfpbsawnfngoffaFri, 29 Jul 2022 00:00:00 GMTRandom Quantum Circuits
https://scholar.archive.org/work/57bh7e2hhbawvbw6cngsbn555e
Quantum circuits -- built from local unitary gates and local measurements -- are a new playground for quantum many-body physics and a tractable setting to explore universal collective phenomena far-from-equilibrium. These models have shed light on longstanding questions about thermalization and chaos, and on the underlying universal dynamics of quantum information and entanglement. In addition, such models generate new sets of questions and give rise to phenomena with no traditional analog, such as new dynamical phases in quantum systems that are monitored by an external observer. Quantum circuit dynamics is also topical in view of experimental progress in building digital quantum simulators that allow control of precisely these ingredients. Randomness in the circuit elements allows a high level of theoretical control, with a key theme being mappings between real-time quantum dynamics and effective classical lattice models or dynamical processes. Many of the universal phenomena that can be identified in this tractable setting apply to much wider classes of more structured many-body dynamics.Matthew P. A. Fisher, Vedika Khemani, Adam Nahum, Sagar Vijaywork_57bh7e2hhbawvbw6cngsbn555eThu, 28 Jul 2022 00:00:00 GMTEnhancing the diversity of self-replicating structures using active self-adapting mechanisms
https://scholar.archive.org/work/hwud2qhyirawfe7del6hbivigq
Numerous varieties of life forms have filled the earth throughout evolution. Evolution consists of two processes: self-replication and interaction with the physical environment and other living things around it. Initiated by von Neumann et al. studies on self-replication in cellular automata have attracted much attention, which aim to explore the logical mechanism underlying the replication of living things. In nature, competition is a common and spontaneous resource to drive self-replications, whereas most cellular-automaton-based models merely focus on some self-protection mechanisms that may deprive the rights of other artificial life (loops) to live. Especially, Huang et al. designed a self-adaptive, self-replicating model using a greedy selection mechanism, which can increase the ability of loops to survive through an occasionally abandoning part of their own structural information, for the sake of adapting to the restricted environment. Though this passive adaptation can improve diversity, it is always limited by the loop's original structure and is unable to evolve or mutate new genes in a way that is consistent with the adaptive evolution of natural life. Furthermore, it is essential to implement more complex self-adaptive evolutionary mechanisms not at the cost of increasing the complexity of cellular automata. To this end, this article proposes new self-adaptive mechanisms, which can change the information of structural genes and actively adapt to the environment when the arm of a self-replicating loop encounters obstacles, thereby increasing the chance of replication. Meanwhile, our mechanisms can also actively add a proper orientation to the current construction arm for the sake of breaking through the deadlock situation. Our new mechanisms enable active self-adaptations in comparison with the passive mechanism in the work of Huang et al. which is achieved by including a few rules without increasing the number of cell states as compared to the latter. Experiments demonstrate that this active self-adaptability can bring more diversity than the previous mechanism, whereby it may facilitate the emergence of various levels in self-replicating structures.Wenli Xu, Chunrong Wu, Qinglan Peng, Jia Lee, Yunni Xia, Shuji Kawasakiwork_hwud2qhyirawfe7del6hbivigqTue, 26 Jul 2022 00:00:00 GMTRandom Feedback Shift Registers, and the Limit Distribution for Largest Cycle Lengths
https://scholar.archive.org/work/coxdxagzfjaynd3ucb64e25tvi
For a random binary noncoalescing feedback shift register of width n, with all 2^2^n-1 possible feedback functions f equally likely, the process of long cycle lengths, scaled by dividing by N=2^n, converges in distribution to the same Poisson-Dirichlet limit as holds for random permutations in 𝒮_N, with all N! possible permutations equally likely. Such behavior was conjectured by Golomb, Welch, and Goldstein in 1959.Richard Arratia and E. Rodney Canfield and Alfred W. Haleswork_coxdxagzfjaynd3ucb64e25tviSun, 24 Jul 2022 00:00:00 GMTPrivate High-Dimensional Hypothesis Testing
https://scholar.archive.org/work/3ifnrb5cd5gudlvmfx57fs7jwu
We provide improved differentially private algorithms for identity testing of high-dimensional distributions. Specifically, for d-dimensional Gaussian distributions with known covariance Σ, we can test whether the distribution comes from 𝒩(μ^*, Σ) for some fixed μ^* or from some 𝒩(μ, Σ) with total variation distance at least α from 𝒩(μ^*, Σ) with (ε, 0)-differential privacy, using only Õ(d^1/2/α^2 + d^1/3/α^4/3·ε^2/3 + 1/α·ε) samples if the algorithm is allowed to be computationally inefficient, and only Õ(d^1/2/α^2 + d^1/4/α·ε) samples for a computationally efficient algorithm. We also provide a matching lower bound showing that our computationally inefficient algorithm has optimal sample complexity. We also extend our algorithms to various related problems, including mean testing of Gaussians with bounded but unknown covariance, uniformity testing of product distributions over {-1, 1}^d, and tolerant testing. Our results improve over the previous best work of Canonne et al. for both computationally efficient and inefficient algorithms, and even our computationally efficient algorithm matches the optimal non-private sample complexity of O(√(d)/α^2) in many standard parameter settings. In addition, our results show that, surprisingly, private identity testing of d-dimensional Gaussians can be done with fewer samples than private identity testing of discrete distributions over a domain of size d , which refutes a conjectured lower bound of .Shyam Narayananwork_3ifnrb5cd5gudlvmfx57fs7jwuSun, 24 Jul 2022 00:00:00 GMTModeling and Study of quantum cellular automata logic gates using Hopfield neural networks
https://scholar.archive.org/work/pofo3jljovhihc53dcabwkaayq
CMOS technology miniaturization limits have provided new alternative technologies, Quantum cellular automata (QCA) is a new technology in nanometer scale as one of the alternatives, QCA technology has large potential in terms of high space density and power dissipation with the development of faster computers and lower power consumption. This paper proposes the use of Hopfield neural network design of simple QCA cells and study device level uncertainties like stable polarization at the output cell, near to ground state configuration of QCA cells, nonlinear cell to cell response of QCA cell are also studied. The energy required for the output of qca cell are defined and study the non linear response using linear neurons thereby bringing QCA cells near to stable or ground state configurations. The unconstrained non-linear optimization method is used here to minimize the polarization of undesirable cells. This study is helpful to synthesize the QCA system thereby to achieve high speed and errorless QCA circuit.ganesh E Nwork_pofo3jljovhihc53dcabwkaayqFri, 22 Jul 2022 00:00:00 GMTArchitectural Systemic Approach: The Serpentine Gallery 2005, a Reciprocal Frame Case Study
https://scholar.archive.org/work/ulqxbtpp6ngrjki3ysgpdkk4cy
The application of the systemic approach in architecture aims to promote an integral, holistic view of the architectural design process. The literature reviewed calls for models with systemic behavior, and for these models to be applied in concrete cases. This paper proposes an original approach, using the foundation matrix and the constructive logic matrix. Both matrices are part of a developing model that is being tested on a case study. The work presented here had two objectives: to check this part of the model and gain more knowledge about the model itself. The selected case study, the 2005 Serpentine Gallery Pavilion, is a contemporary ephemeral construction of significant architectural interest. It is a reciprocal frame structure, linked to the construction history. The methodology used was a systemic analysis. In the first phase of the analysis, the reciprocal structures documented historically in the West were reviewed. The other two phases corresponded to the application of the two model matrices. Conceptual diagramming was used in all phases of the process. The results show the importance of the study of historical building solutions. The use of matrices facilitates the identification and understanding of the operations carried out in the design process of the case study. Matrices favor the organization of concepts and relationships from through a systemic approach. Understanding generation operations in an integrated way leads to a type of knowledge (relational knowledge) that allows architecture to be thought about in a holistic way. This makes the systemic view of art and technology as a unit possible, attending to the whole complexity of architectural thinking.Beatriz del Río-Calleja, Joaquín Grau Enguix, Alfonso García-Santoswork_ulqxbtpp6ngrjki3ysgpdkk4cyWed, 20 Jul 2022 00:00:00 GMTTwo-Dimensional Typewriter Automata
https://scholar.archive.org/work/umnjpsqtjbgpbeh3upeowjrocy
A typewriter automaton is a special variant of a two-dimensional automaton that receives two-dimensional words as input and is only capable of moving its input head through its input word in three directions: downward, leftward, and rightward. In addition, downward and leftward moves may only be made via a special "reset" move that simulates the action of a typewriter's carriage return. In this paper, we initiate the study of the typewriter automaton model and relate it to similar models, including three-way two-dimensional automata, boustrophedon automata, and returning automata. We study the recognition powers of the typewriter automaton model, establish closure properties of the class of languages recognized by the model, and consider operational state complexity bounds for the specific operation of row concatenation. We also provide a variety of potential future research directions pertaining to the model.Taylor J. Smithwork_umnjpsqtjbgpbeh3upeowjrocyWed, 20 Jul 2022 00:00:00 GMTAll Paths Lead to Rome
https://scholar.archive.org/work/t7ymr3ecmzgahme5kcayjjio2y
All roads lead to Rome is the core idea of the puzzle game Roma. It is played on an n × n grid consisting of quadratic cells. Those cells are grouped into boxes of at most four neighboring cells and are either filled, or to be filled, with arrows pointing in cardinal directions. The goal of the game is to fill the empty cells with arrows such that each box contains at most one arrow of each direction and regardless where we start, if we follow the arrows in the cells, we will always end up in the special Roma-cell. In this work, we study the computational complexity of the puzzle game Roma and show that completing a Roma board according to the rules is an -complete task, counting the number of valid completions is #Ptime-complete, and determining the number of preset arrows needed to make the instance uniquely solvable is Σ_2^P-complete. We further show that the problem of completing a given Roma instance on an n× n board cannot be solved in time 𝒪(2^o(n)) under ETH and give a matching dynamic programming algorithm based on the idea of Catalan structures.Kevin Goergen, Henning Fernau, Esther Oest, Petra Wolfwork_t7ymr3ecmzgahme5kcayjjio2yTue, 19 Jul 2022 00:00:00 GMT