Multicore and FPGA implementations of emotional-based agent architectures

The final publication is available at Springer via http://dx.doi.org/10.1007/s11227-014-1307-6.Control architectures based on Emotions are becoming promising solutions for the implementation of future robotic agents. The basic controllers of the architecture are the emotional processes that decide which behaviors of the robot must activate to fulfill the objectives. The number of emotional processes increases (hundreds of millions/s) with the complexity level of the application, reducing the processing capacity of the main processor to solve complex problems (millions of decisions in a given instant). However, the potential parallelism of the emotional processes permits their execution in parallel on FPGAs or Multicores, thus enabling slack computing in the main processor to tackle more complex dynamic problems. In this paper, an emotional architecture for mobile robotic agents is presented. The workload of the emotional processes is evaluated. Then, the main processor is extended with FPGA co-processors through Ethernet link. The FPGAs will be in charge of the execution of the emotional processes in parallel. Different Stratix FPGAs are compared to analyze their suitability to cope with the proposed mobile robotic agent applications. The applications are set up taking into account different environmental conditions, robot dynamics and emotional states. Moreover, the applications are run also on Multicore processors to compare their performance in relation to the FPGAs. Experimental results show that Stratix IV FPGA increases the performance in about one order of magnitude over the main processor and solves all the considered problems. Quad-Core increases the performance in 3.64 times, allowing to tackle about 89 % of the considered problems. Quad-Core has a lower cost than a Stratix IV, so more adequate solution but not for the most complex application. Stratix III could be applied to solve problems with around the double of the requirements that the main processor could support. Finally, a Dual-Core provides slightly better performance than stratix III and it is relatively cheaper.This work was supported in part under Spanish Grant PAID/2012/325 of "Programa de Apoyo a la Investigacion y Desarrollo. Proyectos multidisciplinares", Universitat Politecnica de Valencia, Spain.Domínguez Montagud, CP.; Hassan Mohamed, H.; Crespo, A.; Albaladejo Meroño, J. (2015). Multicore and FPGA implementations of emotional-based agent architectures. Journal of Supercomputing. 71(2):479-507. https://doi.org/10.1007/s11227-014-1307-6S479507712Malfaz M, Salichs MA (2010) Using MUDs as an experimental platform for testing a decision making system for self-motivated autonomous agents. Artif Intell Simul Behav J 2(1):21–44Damiano L, Cañamero L (2010) Constructing emotions. Epistemological groundings and applications in robotics for a synthetic approach to emotions. In: Proceedings of international symposium on aI-inspired biology, The Society for the Study of Artificial Intelligence, pp 20–28Hawes N, Wyatt J, Sloman A (2009) Exploring design space for an integrated intelligent system. Knowl Based Syst 22(7):509–515Sloman A (2009) Some requirements for human-like robots: why the recent over-emphasis on embodiment has held up progress. Creat Brain Like Intell 2009:248–277Arkin RC, Ulam P, Wagner AR (2012) Moral decision-making in autonomous systems: enforcement, moral emotions, dignity, trust and deception. In: Proceedings of the IEEE, Mar 2012, vol 100, no 3, pp 571–589iRobot industrial robots website. http://www.irobot.com/gi/ground/ . Accessed 22 Sept 2014Moravec H (2009) Rise of the robots: the future of artificial intelligence. Scientific American, March 2009. http://www.scientificamerican.com/article/rise-of-the-robots/ . Accessed 14 Oct 2014.Thu Bui L, Abbass HA, Barlow M, Bender A (2012) Robustness against the decision-maker’s attitude to risk in problems with conflicting objectives. IEEE Trans Evolut Comput 16(1):1–19Pedrycz W, Song M (2011) Analytic hierarchy process (AHP) in group decision making and its optimization with an allocation of information granularity. IEEE Trans Fuzzy Syst 19(3):527–539Lee-Johnson CP, Carnegie DA (2010) Mobile robot navigation modulated by artificial emotions. IEEE Trans Syst Man Cybern Part B 40(2):469–480Daglarli E, Temeltas H, Yesiloglu M (2009) Behavioral task processing for cognitive robots using artificial emotions. Neurocomputing 72(13):2835–2844Ventura R, Pinto-Ferreira C (2009) Responding efficiently to relevant stimuli using an emotion-based agent architecture. Neurocomputing 72(13):2923–2930Arkin RC, Ulam P, Wagner AR (2012) Moral decision-making in autonomous systems: enforcement, moral emotions, dignity, trust and deception. Proc IEEE 100(3):571–589Salichs MA, Malfaz M (2012) A new approach to modeling emotions and their use on a decision-making system for artificial agents. Affect Comput IEEE Trans 3(1):56–68Altera Corporation (2011) Stratix III device handbook, vol 1–2, version 2.2. http://www.altera.com/literature/lit-stx3.jsp . Accessed 14 Oct 2014.Altera Corporation (2014) Stratix IV device handbook, vol 1–4, version 5.9. http://www.altera.com/literature/lit-stratix-iv.jsp . Accessed 14 Oct 2014.Naouar MW, Monmasson E, Naassani AA, Slama-Belkhodja I, Patin N (2007) FPGA-based current controllers for AC machine drives: a review. IEEE Trans Ind Electr 54(4):1907–1925Intel Corporation (2014) Desktop 4th generation Intel Core Processor Family, Desktop Intel Pentium Processor Family, and Desktop Intel Celeron Processor Family, Datasheet, vol 1, 2March JL, Sahuquillo J, Hassan H, Petit S, Duato J (2011) A new energy-aware dynamic task set partitioning algorithm for soft and hard embedded real-time systems. 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Embedded GPU and multicore processors for emotional-based mobile robotic agents

Control architectures based on emotions are becoming promising solutions for the implementation of future robotic systems. The basic controllers of this architecture are the emotional processes that decide which behaviors the robot must activate to fulfill the objectives. The number of emotional processes increases (hundreds of millions/s) with the complexity level of the application, limiting the processing capacity of a main processor to solve the complex problems. Fortunately, the potential parallelism of emotional processes permits their execution in parallel, hence enabling the computing power to tackle the complex dynamic problems. In this paper, Graphic Processing Unit (GPU), multicore processors and single instruction multiple data (SIMD) instructions are used to provide parallelism for the emotional processes. Different GPUs, multicore processors and SIMD instruction sets are evaluated and compared to analyze their suitability to cope with robotic applications. The applications are set-up taking into account different environmental conditions, robot dynamics and emotional states. Experimental results show that, despite the fact that GPUs have a bottleneck in the data transmission between the host and the device, the evaluated GTX 670 GPU provides a performance of more than one order of magnitude greater than the initial implementation of the architecture on a single core. Thus, all complex proposed application problems can be solved using the GPU technology in contrast to the first prototype where only 55% of them could be solved. Using AVX SIMD instructions, the performance of the architecture is increased in 3.25 times in relation to the first implementation. Thus, from the 27 proposed applications about 88.8% are solved. In the case of the SSE SIMD instructions, the performance is almost doubled and the robot could solve about 74% of the proposed application problems. The use of AVX and SSE SIMD instructions provides almost the same performance as a quad- and a dual-core, respectively, with the advantage that they do not add any additional hardware cost.This work was supported by the Spanish Ministerio de Economia y Competitividad (MINECO) and by FEDER funds under Grant TIN2012-38341-C04-01 and by Universitat Politecnica de Valencia under Grant PAID/2012/325.Francisco Almenar; Domínguez Montagud, CP.; Hassan Mohamed, H.; Martínez Rubio, JM.; López Rodríguez, PJ. (2016). Embedded GPU and multicore processors for emotional-based mobile robotic agents. Future Generation Computer Systems. 56:192-201. https://doi.org/10.1016/j.future.2015.05.010S1922015

Journal of Real-Time Image Processing manuscript No. (will be inserted by the editor) Evaluation of real-time LBP computing in multiple architectures

Abstract Local Binary Pattern (LBP) is a texture operator that is used in several different computer vision applications requiring, in many cases, real-time operation in multiple computing platforms. The irruption of new video standards has increased the typical resolutions and frame rates, which need considerable computational performance. Since LBP is essentially a pixel operator that scales with image size, typical straightforward implementations are usually insufficient to meet these requirements. To identify the solutions that maximize the performance of the real-time LBP extraction, we compare a series different implementations in terms of computational performance and energy efficiency while analyzing the different optimizations that can be made to reach real-time performance on multiple platforms and their different available computing resources. Our contribution addresses the extensive survey of LBP implementations in different platforms that can be found in the literature. To provide for a more complete evaluation, we have implemented the LBP algorithms in several platforms such as Graphics Processing Units, mobile processors and a hybrid programming model image coprocessor. We have extended the evaluation of some of the solutions that can be found in previous work. In addition, we publish the source code of our implementations

Arquitectura de Agente Emocional para Aplicaciones de Control en Tiempo Real

Tesis por compendioArtificial agents are a technology suitable for solving problems. Agents can perform tasks that their users cannot and/or do not want to accomplish. Agents are systems with a significant degree of autonomy. Even being autonomous in their behavior, they assume the users' goals as their own goals, because there is an agreement between the agent and the user. It is a powerful technology, and the research on this field is very active. As agents are complex systems, it is necessary to define development frameworks that facilitate their conception, design and construction. We name these frameworks, artificial agent architectures. Each architecture is characterized by a few key ideas related to the way the agent represents its knowledge about the world, and how it organizes its behavior. We call these key ideas a paradigm. In this work, an artificial agent's architecture is proposed. In this architecture the organization of the behavior is emotionally driven. It is a bio-inspired architecture. The emotion in this case, however, is a very simplified version of the emotional process in the natural emotional agents. Although other agent architectures based on emotions have been proposed, they have been usually focused on the social skills of the agents, normally to interact with people. This situation could have been caused due to the knowledge we had about the importance of the emotion in the social relations between human beings, when people recognize the internal state of the others, or show their own internal states, and the emotional communication influences their behavior. However, the fundamental role of the emotion in a wide range of cognitive processes is being recognized because of the recent research in psychology and neuroscience. Emotions seem to make an essential contribution in processes such as perception, learning, memory, decision-making and problem solving. Deliberative rational thoughts themselves would be directed by emotions. Given this new view about the emotion, in this thesis, we have investigated the role of the emotions in the cognitive processes of an artificial agent, related them to the general decision making problem, not just the social interaction problem. As an example, in the application considered as a case study in this project, the emotional agent controls a mobile robot platform, in which there is not an important behavior layer of social interaction, and the emotional processes primarily motivate behaviors related to problems in a physical environment, with objects, parts, or areas of operation and navigation. In this thesis, we have defined a specification for the proposed emotional agent architecture, and have discussed the implementation aspects of it.Los agentes artificiales constituyen una tecnología de apoyo para la resolución de problemas. Un agente es un sistema con un grado significativo de autonomía, lo que le permite descargar a su usuario de tareas que éste no puede o no quiere realizar. Aun siendo autónomo en sus comportamientos, el agente asume los objetivos de su usuario como propios, ya que existe un contrato entre el agente y su representado. Se trata de una tecnología potente y que interesa desarrollar, con lo que el área de investigación en agentes está abierta y hay un esfuerzo continuo para construir agentes con cada vez mejores prestaciones. Siendo los agentes sistemas complejos, resulta necesario definir marcos de desarrollo que permitan concebirlos, diseñarlos y construirlos. Conocemos a estos marcos como arquitecturas de agentes artificiales. Cada una de estas arquitecturas se caracteriza por ciertas ideas clave, relacionadas con la forma en que el agente representa su conocimiento y organiza su comportamiento, en lo que se denomina un paradigma. Sin duda, queda mucho recorrido en este campo - ampliando por ejemplo las áreas de aplicación, o permitiendo funcionalidades adicionales, o aumentando la eficiencia de los procesos implicados, tanto en lo relativo al comportamiento del agente cuando éste está en explotación, como durante el propio proceso de construcción y validación del sistema. En este trabajo se propone una arquitectura de agente artificial en el que la organización del comportamiento está dirigida por un proceso emocional. Se trata de una arquitectura bio-inspirada. La emoción en este caso, sin embargo, es una versión muy simplificada del proceso emocional en los agentes emocionales naturales. Aunque se han definido otras arquitecturas de agentes artificiales basadas en emociones, han sido enfocadas, sobre todo, a construir agentes con habilidades sociales; normalmente para interactuar con las personas. Posiblemente esto ha sido debido a que ya hace mucho que se aceptaba la importancia de la emoción en las relaciones sociales entre los seres humanos; cuando éstos interpretan el estado interno de los demás o expresan su propio estado, alterando con ello sus comportamientos. Sin embargo, el papel fundamental de la emoción en un amplio espectro de procesos cognitivos está siendo reconocido a raíz de la investigación en psicología y neurología. Las emociones parecen contribuir de forma esencial en procesos como la percepción, el aprendizaje, la memoria, la toma de decisiones o la resolución de problemas. El propio pensamiento deliberativo racional estaría dirigido por las emociones. Teniendo en cuenta esta nueva visión de las emociones, en este trabajo se ha investigado el rol de la emoción en los procesos cognitivos de un agente artificial relacionados con la toma de decisiones en general, no sólo en lo relativo a los procesos de interrelación social. Así por ejemplo, en la aplicación considerada como caso de estudio de este trabajo, el agente emocional controla una plataforma de robot móvil de servicio, en la que no hay una capa de comportamiento social importante, y donde los procesos emocionales motivan fundamentalmente los comportamientos relacionados con problemas surgidos en un entorno físico, con objetos, piezas, o espacios de operación y navegación. En esta tesis se define una especificación para la arquitectura de agente emocional artificial propuesta y se discute aspectos de implementación de dicha arquitectura.Els agents artificials constitueixen una tecnologia de suport per a la resolució de problemes. Un agent és un sistema amb un grau significatiu d'autonomia, el que li permet descarregar al seu usuari de tasques que aquest no pot o no vol fer. Fins i tot sent autònom en els seus comportaments, l'agent assumeix els objectius del seu usuari com a propis, ja que hi ha un contracte entre l'agent i el seu representat. Es tracta d'una tecnologia potent i que interessa desenvolupar, de manera que l'àrea de recerca en agents està oberta i hi ha un esforç continu per construir agents amb cada vegada millors prestacions. Sent els agents sistemes complexos, resulta necessari definir marcs de desenvolupament que puguen permetre concebre'ls, dissenyar-los i construir-los. Coneixem a aquests marcs com arquitectures d'agents artificials. Cadascuna d'aquestes arquitectures es caracteritza per certes idees clau, relacionades amb la forma en què l'agent representa el seu coneixement i organitza el seu comportament, en el que s'anomena un paradigma. Sens dubte, queda molt de recorregut en aquest camp - ampliant les àrees d'aplicació, o permetent funcionalitats addicionals, o augmentant l'eficiència dels processos implicats, tant pel que fa al comportament de l'agent quan aquest està en explotació, com durant el mateix procés de construcció i validació del sistema. En aquest treball es proposa una arquitectura d'agent artificial en què l'organització del comportament està dirigida per un procés emocional. Es tracta d'una arquitectura bio-inspirada. L'emoció en aquest cas, però, és una versió molt simplificada del procés emocional en els agents emocionals naturals. Tot i que s'han definit altres arquitectures d'agents artificials basades en emocions, han estat enfocades, sobretot, a construir agents amb habilitats socials; normalment per interactuar amb les persones. Possiblement això ha segut perquè ja fa molt que s'acceptava la importància de l'emoció en les relacions socials entre els éssers humans; quan aquests interpreten l'estat intern dels altres o expressen el seu propi estat, alterant amb això els seus comportaments. No obstant això, el paper fonamental de l'emoció en un ampli espectre de processos cognitius està sent reconegut arran de la investigació en psicologia i neurologia. Les emocions semblen contribuir de forma essencial en processos com la percepció, l'aprenentatge, la memòria, la presa de decisions o la resolució de problemes. El mateix pensament deliberatiu racional estaria dirigit per les emocions. Tenint en compte aquesta nova visió de les emocions, en aquest treball s'ha investigat el paper de l'emoció en els processos cognitius d'un agent artificial relacionats amb la presa de decisions en general, no només pel que fa als processos d'interrelació social. Així per exemple, en l'aplicació considerada com a cas d'estudi d'aquest treball, l'agent emocional controla una plataforma de robot mòbil de servei, en què no hi ha una capa de comportament social important, i on els processos emocionals motiven fonamentalment els comportaments relacionats amb problemes sorgits en un entorn físic, amb objectes, peces, o espais d'operació i navegació. En aquesta tesi es defineix una especificació per a l'arquitectura d'agent emocional artificial proposta i es discuteixen aspectes d'implementació de la arquitectura.Domínguez Montagud, CP. (2017). Arquitectura de Agente Emocional para Aplicaciones de Control en Tiempo Real [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/86223TESISCompendi

Parallel Architectures for Planetary Exploration Requirements (PAPER)

The Parallel Architectures for Planetary Exploration Requirements (PAPER) project is essentially research oriented towards technology insertion issues for NASA's unmanned planetary probes. It was initiated to complement and augment the long-term efforts for space exploration with particular reference to NASA/LaRC's (NASA Langley Research Center) research needs for planetary exploration missions of the mid and late 1990s. The requirements for space missions as given in the somewhat dated Advanced Information Processing Systems (AIPS) requirements document are contrasted with the new requirements from JPL/Caltech involving sensor data capture and scene analysis. It is shown that more stringent requirements have arisen as a result of technological advancements. Two possible architectures, the AIPS Proof of Concept (POC) configuration and the MAX Fault-tolerant dataflow multiprocessor, were evaluated. The main observation was that the AIPS design is biased towards fault tolerance and may not be an ideal architecture for planetary and deep space probes due to high cost and complexity. The MAX concepts appears to be a promising candidate, except that more detailed information is required. The feasibility for adding neural computation capability to this architecture needs to be studied. Key impact issues for architectural design of computing systems meant for planetary missions were also identified

The fast multipole method at exascale

This thesis presents a top to bottom analysis on designing and implementing fast algorithms for current and future systems. We present new analysis, algorithmic techniques, and implementations of the Fast Multipole Method (FMM) for solving N- body problems. We target the FMM because it is broadly applicable to a variety of scientific particle simulations used to study electromagnetic, fluid, and gravitational phenomena, among others. Importantly, the FMM has asymptotically optimal time complexity with guaranteed approximation accuracy. As such, it is among the most attractive solutions for scalable particle simulation on future extreme scale systems. We specifically address two key challenges. The first challenge is how to engineer fast code for today’s platforms. We present the first in-depth study of multicore op- timizations and tuning for FMM, along with a systematic approach for transforming a conventionally-parallelized FMM into a highly-tuned one. We introduce novel opti- mizations that significantly improve the within-node scalability of the FMM, thereby enabling high-performance in the face of multicore and manycore systems. The second challenge is how to understand scalability on future systems. We present a new algorithmic complexity analysis of the FMM that considers both intra- and inter- node communication costs. Using these models, we present results for choosing the optimal algorithmic tuning parameter. This analysis also yields the surprising prediction that although the FMM is largely compute-bound today, and therefore highly scalable on current systems, the trajectory of processor architecture designs, if there are no significant changes could cause it to become communication-bound as early as the year 2015. This prediction suggests the utility of our analysis approach, which directly relates algorithmic and architectural characteristics, for enabling a new kind of highlevel algorithm-architecture co-design. To demonstrate the scientific significance of FMM, we present two applications namely, direct simulation of blood which is a multi-scale multi-physics problem and large-scale biomolecular electrostatics. MoBo (Moving Boundaries) is the infrastruc- ture for the direct numerical simulation of blood. It comprises of two key algorithmic components of which FMM is one. We were able to simulate blood flow using Stoke- sian dynamics on 200,000 cores of Jaguar, a peta-flop system and achieve a sustained performance of 0.7 Petaflop/s. The second application we propose as future work in this thesis is biomolecular electrostatics where we solve for the electrical potential using the boundary-integral formulation discretized with boundary element methods (BEM). The computational kernel in solving the large linear system is dense matrix vector multiply which we propose can be calculated using our scalable FMM. We propose to begin with the two dielectric problem where the electrostatic field is cal- culated using two continuum dielectric medium, the solvent and the molecule. This is only a first step to solving biologically challenging problems which have more than two dielectric medium, ion-exclusion layers, and solvent filled cavities. Finally, given the difficulty in producing high-performance scalable code, productivity is a key concern. Recently, numerical algorithms are being redesigned to take advantage of the architectural features of emerging multicore processors. These new classes of algorithms express fine-grained asynchronous parallelism and hence reduce the cost of synchronization. We performed the first extensive performance study of a recently proposed parallel programming model, called Concurrent Collections (CnC). In CnC, the programmer expresses her computation in terms of application-specific operations, partially-ordered by semantic scheduling constraints. The CnC model is well-suited to expressing asynchronous-parallel algorithms, so we evaluate CnC using two dense linear algebra algorithms in this style for execution on state-of-the-art mul- ticore systems. Our implementations in CnC was able to match and in some cases even exceed competing vendor-tuned and domain specific library codes. We combine these two distinct research efforts by expressing FMM in CnC, our approach tries to marry performance with productivity that will be critical on future systems. Looking forward, we would like to extend this to distributed memory machines, specifically implement FMM in the new distributed CnC, distCnC to express fine-grained paral- lelism which would require significant effort in alternative models.Ph.D

On the synthesis and processing of high quality audio signals by parallel computers

This work concerns the application of new computer architectures to the creation and manipulation of high-quality audio bandwidth signals. The configuration of both the hardware and software in such systems falls under consideration in the three major sections which present increasing levels of algorithmic concurrency. In the first section, the programs which are described are distributed in identical copies across an array of processing elements; these programs run autonomously, generating data independently, but with control parameters peculiar to each copy: this type of concurrency is referred to as isonomic}The central section presents a structure which distributes tasks across an arbitrary network of processors; the flow of control in such a program is quasi- indeterminate, and controlled on a demand basis by the rate of completion of the slave tasks and their irregular interaction with the master. Whilst that interaction is, in principle, deterministic, it is also data-dependent; the dynamic nature of task allocation demands that no a priori knowledge of the rate of task completion be required. This type of concurrency is called dianomic? Finally, an architecture is described which will support a very high level of algorithmic concurrency. The programs which make efficient use of such a machine are designed not by considering flow of control, but by considering flow of data. Each atomic algorithmic unit is made as simple as possible, which results in the extensive distribution of a program over very many processing elements. Programs designed by considering only the optimum data exchange routes are said to exhibit systolic^ concurrency. Often neglected in the study of system design are those provisions necessary for practical implementations. It was intended to provide users with useful application programs in fulfilment of this study; the target group is electroacoustic composers, who use digital signal processing techniques in the context of musical composition. Some of the algorithms in use in this field are highly complex, often requiring a quantity of processing for each sample which exceeds that currently available even from very powerful computers. Consequently, applications tend to operate not in 'real-time' (where the output of a system responds to its input apparently instantaneously), but by the manipulation of sounds recorded digitally on a mass storage device. The first two sections adopt existing, public-domain software, and seek to increase its speed of execution significantly by parallel techniques, with the minimum compromise of functionality and ease of use. Those chosen are the general- purpose direct synthesis program CSOUND, from M.I.T., and a stand-alone phase vocoder system from the C.D.P..(^4) In each case, the desired aim is achieved: to increase speed of execution by two orders of magnitude over the systems currently in use by composers. This requires substantial restructuring of the programs, and careful consideration of the best computer architectures on which they are to run concurrently. The third section examines the rationale behind the use of computers in music, and begins with the implementation of a sophisticated electronic musical instrument capable of a degree of expression at least equal to its acoustic counterparts. It seems that the flexible control of such an instrument demands a greater computing resource than the sound synthesis part. A machine has been constructed with the intention of enabling the 'gestural capture' of performance information in real-time; the structure of this computer, which has one hundred and sixty high-performance microprocessors running in parallel, is expounded; and the systolic programming techniques required to take advantage of such an array are illustrated in the Occam programming language

Scalable String and Suffix Sorting: Algorithms, Techniques, and Tools

This dissertation focuses on two fundamental sorting problems: string sorting and suffix sorting. The first part considers parallel string sorting on shared-memory multi-core machines, the second part external memory suffix sorting using the induced sorting principle, and the third part distributed external memory suffix sorting with a new distributed algorithmic big data framework named Thrill.Comment: 396 pages, dissertation, Karlsruher Instituts f\"ur Technologie (2018). arXiv admin note: text overlap with arXiv:1101.3448 by other author