On Restricting Real-Valued Genotypes in Evolutionary Algorithms

Real-valued genotypes together with the variation operators, mutation and crossover, constitute some of the fundamental building blocks of Evolutionary Algorithms. Real-valued genotypes are utilized in a broad range of contexts, from weights in Artificial Neural Networks to parameters in robot control systems. Shared between most uses of real-valued genomes is the need for limiting the range of individual parameters to allowable bounds. In this paper we will illustrate the challenge of limiting the parameters of real-valued genomes and analyse the most promising method to properly limit these values. We utilize both empirical as well as benchmark examples to demonstrate the utility of the proposed method and through a literature review show how the insight of this paper could impact other research within the field. The proposed method requires minimal intervention from Evolutionary Algorithm practitioners and behaves well under repeated application of variation operators, leading to better theoretical properties as well as significant differences in well-known benchmarks

Evolved embodied phase coordination enables robust quadruped robot locomotion

Overcoming robotics challenges in the real world requires resilient control systems capable of handling a multitude of environments and unforeseen events. Evolutionary optimization using simulations is a promising way to automatically design such control systems, however, if the disparity between simulation and the real world becomes too large, the optimization process may result in dysfunctional real-world behaviors. In this paper, we address this challenge by considering embodied phase coordination in the evolutionary optimization of a quadruped robot controller based on central pattern generators. With this method, leg phases, and indirectly also inter-leg coordination, are influenced by sensor feedback.By comparing two very similar control systems we gain insight into how the sensory feedback approach affects the evolved parameters of the control system, and how the performances differs in simulation, in transferal to the real world, and to different real-world environments. We show that evolution enables the design of a control system with embodied phase coordination which is more complex than previously seen approaches, and that this system is capable of controlling a real-world multi-jointed quadruped robot.The approach reduces the performance discrepancy between simulation and the real world, and displays robustness towards new environments.Comment: 9 page

Two-Stage Transfer Learning for Heterogeneous Robot Detection and 3D Joint Position Estimation in a 2D Camera Image using CNN

Collaborative robots are becoming more common on factory floors as well as regular environments, however, their safety still is not a fully solved issue. Collision detection does not always perform as expected and collision avoidance is still an active research area. Collision avoidance works well for fixed robot-camera setups, however, if they are shifted around, Eye-to-Hand calibration becomes invalid making it difficult to accurately run many of the existing collision avoidance algorithms. We approach the problem by presenting a stand-alone system capable of detecting the robot and estimating its position, including individual joints, by using a simple 2D colour image as an input, where no Eye-to-Hand calibration is needed. As an extension of previous work, a two-stage transfer learning approach is used to re-train a multi-objective convolutional neural network (CNN) to allow it to be used with heterogeneous robot arms. Our method is capable of detecting the robot in real-time and new robot types can be added by having significantly smaller training datasets compared to the requirements of a fully trained network. We present data collection approach, the structure of the multi-objective CNN, the two-stage transfer learning training and test results by using real robots from Universal Robots, Kuka, and Franka Emika. Eventually, we analyse possible application areas of our method together with the possible improvements.Comment: 6+n pages, ICRA 2019 submissio

Architectural aspects of self-aware and self-expressive computing systems: from psychology to engineering

Work on human self-Awareness is the basis for a framework to develop computational systems that can adaptively manage complex dynamic tradeoffs at runtime. An architectural case study in cloud computing illustrates the framework's potential benefits

Enabling Participants to Play Rhythmic Solos Within a Group via Auctions

The paper presents the interactive music system SoloJam, which allows a group of participants with little or no musical training to effectively play together in a ``band-like'' setting. It allows the participants to take turns playing solos made up of rhythmic pattern sequences. We specify the issue at hand for allowing such participation as being the requirement of decentralised coherent circulation of playing solos. This is to be realised by some form of intelligence within the devices used for participation. Here we take inspiration from the Economic Sciences, and propose this intelligence to take the form of making devices possessing the capability of evaluating their utility of playing the next solo, the capability of holding auctions, and of bidding within them. We show that holding auctions and bidding within them enables decentralisation of co-ordinating solo circulation, and a properly designed utility function enables coherence in the musical output. The approach helps achieve decentralised coherent circulation with artificial agents simulating human participants. The effectiveness of the approach is further supported when human users participate. As a result, the approach is shown to be effective at enabling participants with little or no musical training to play together in SoloJam

A Topical Review on Executive Functioning in Chronic Non-malignant Pain: Do Different Neurocognitive Dysfunctions in Chronic Non-malignant Pain Reflect a Common Underlying Process?

Clinical observations reveal that cognitive impairments are frequently reported in chronic non-malignant pain patients, and impairments in memory, attentional and executive functions have been found by performance-based neuropsychological tests. To days date, no systematic review has been conducted on cognitive impairment in this patient group. There is a need for clarification and systematization of the studies in this field. The aim of this study was to conduct a topical review on executive impairments in chronic pain, and systematize findings based on theoretical frameworks on executive functions and models of pain and attention. A database search identified 30 studies where evidence point towards deficits in executive function in chronic non-malignant pain. It is here concluded, based on the existing evidence, that the impairments might reflect an underlying deficit in executive control. This is supported by both clinical and experimental studies. In addition, executive control deficits are closely correlated with subjective reports of cognitive difficulties. This has implications for treatment of these symptoms. There may be possibilities to target this specific deficit by high-demanding working memory training programs. Future research should use methods from cognitive psychology to test out theory-driven hypotheses about the possibility of an underlying executive control deficit in chronic pain.Oppgaven er klausulert i 1 år. Tilgjengelig fra 2014-06-04

The role of organizational factors in how efficiency-thoroughness trade-offs potentially affect clinical quality dimensions – a review of the literature

Purpose The purpose of this paper is to increase knowledge of the role organizational factors have in how health personnel make efficiency-thoroughness trade-offs, and how these trade-offs potentially affect clinical quality dimensions. Design/methodology/approach The paper is a thematic synthesis of the literature concerning health personnel working in clinical, somatic healthcare services, organizational factors and clinical quality. Findings Identified organizational factors imposing trade-offs were high workload, time limits, inappropriate staffing and limited resources. The trade-offs done by health personnel were often trade-offs weighing thoroughness (e.g. providing extra handovers or working additional hours) in an environment weighing efficiency (e.g. ward routines of having one single handover and work-hour regulations limiting physicians' work hours). In this context, the health personnel functioned as regulators, balancing efficiency and thoroughness and ensuring patient safety and patient centeredness. However, sometimes organizational factors limited health personnel's flexibility in weighing these aspects, leading to breached medication rules, skipped opportunities for safety debriefings and patients being excluded from medication reviews. Originality/value Balancing resources and healthcare demands while maintaining healthcare quality is a large part of health personnel's daily work, and organizational factors are suspected to affect this balancing act. Yet, there is limited research on this subject. With the expected aging of the population and the subsequent pressure on healthcare services' resources, the balancing between efficiency and thoroughness will become crucial in handling increased healthcare demands, while maintaining high-quality care.publishedVersio