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      <title-group>
        <article-title>Collaborative Systems: Learning and Working Together</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Lukas Esterle</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Aarhus University and DIGIT</institution>
          ,
          <country country="DK">Denmark</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Autonomous systems interacting and collaborating need to understand their individual and collective goals as well as their individual capabilities. This keynote outlined challenges and approaches to enable systems to collaborate. Additionally we explore approaches to enable systems to learn and exploit the diverse knowledge of the individual agents in a collaborative manner. The rise of computing systems is unbroken, spreading from our wrist, pockets, to our cars, houses, and even cities [1]. Individual smart devices are being deployed and distributed around our environment with their very individual goals, resources, and capabilities [2, 3]. Systems therefore collaborate only on accident or if they have explicitly been designed to do so [4]. This leads to many systems operating with limited performance as they interfere with each other in the environment. The potential of collaboration with initially unknown systems, that might be able to support each other, is completely untapped. In previous work we relied on common implementations and knowledge when utilising nature-inspired approaches. In contrast, we aim to close the gap and enable systems to acknowledge each other and build upon their individual knowledge and capabilities in more recent and ongoing work.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;online multi-object k-coverage</kwd>
        <kwd>team formation</kwd>
        <kwd>autonomous adaptation</kwd>
        <kwd>federated learning</kwd>
      </kwd-group>
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      <p>
        communication efort required systems to have knowledge about others in their respective
environments in order to target their advertisement [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. As an alternative to direct message
exchanges, [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] utilised Reynolds’ flocking mechanism and adjusted the cohesion and separation
parameter dependent on the number of agents in the environment. For this, entropy was used
as a mechanism to attract and repel other agents.
      </p>
      <p>
        [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ] explored approaches where the agents willingness to interact is utilised to make local
decisions. This willingness is influenced by the motion of the target. Specifically, the willingness
of an agent to cover another object is proportional to the similarity of the direction of movement.
This way we can expect the agent to cover the object for an extended period of time. [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ], inspired
by the feeding techniques of humpback whales and hyenas, enabled individual agents to take
diferent tasks depending on how others are currently operating. Here, agents will deliberately
observe the environment when all objects are covered suficiently. This leads to higher detection
rates and better assignment of agents to individual objects while keeping over-provisioning
low. [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] investigated from where coordination control should be coming and created dedicated
observer and tracker agents. Observers are tasked to roam the environment to detect new
objects while tracker are dedicated to follow those object and provision them accordingly.
Tracker agents are either controlled by observers or can be operate autonomously. Finally, [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]
developed an near-optimised approach to solve the online multi-object -coverage problem
utilising linear programming in an aggregate computing framework.
2. Learning together
In all these cases, agents needed to know about each other. This would require developers
of diferent agents to agree on and adhere to common interfaces and standards. In order
to overcome this issue, future autonomous systems are required to have an awareness of
other agents. [
        <xref ref-type="bibr" rid="ref3">11, 3, 12</xref>
        ] described diferent levels of such an awareness. The awareness of
others can vary from simple stimulus-, time-, interaction-, to more complex goal-awareness.
However, for a simple interaction, we can argue that at least time-awareness is required in
order to anticipate external stimuli. With more awareness and deeper understanding of the
situation (e.g. interaction- and goal-awareness), autonomous systems can operate towards
collaborative behaviour. We later expanded the concept towards competence-awareness [13] to
give autonomous systems the awareness of competences of themselves and others. Only with
knowledge of the potential capabilities of others, we can start exploring possible collaborative
actions purposefully and beyond random action exploration.
      </p>
      <p>To overcome collaborative challenges, we recently started to explore potentials of
collaborative multi-agent learning. Here we explore various strands of research around deep learning and
aim to bring those strands together [14]. Specifically, we explore federated learning together
with early exits and split computing. Federated learning are techniques where the knowledge of
individual learners can be combined in a larger model [15]. By sharing the trained models only,
rather than the actual training input, privacy concerns can be mitigated. This is beneficial when
the individual learners are unknown or change at runtime. Usually, the tasks for which the
networks are trained are known to all agents. However individual agents could utilise available
data to estimate the tasks for which a network has been trained by another agent, allowing one
agents to draw conclusion about the inference capabilities of another agent. Overall,
trustworthiness and correctness can be verified by the individual agents upon receiving the networks by
utilising previous training data before merging received networks with local networks.</p>
      <p>Early exits is a concept allowing deep neural networks to not execute all neural layers but
stop execution at earlier neural layers either because satisfactory results are achieved or if later
layers should be executed at another computing location (e.g. from transferring computation
from the edge to the cloud) [16]. We specifically work towards approaches where we utilise
early exits in combination with federated learning. While general knowledge is shared with
other agents, specific knowledge is retained at the individual agent. By sharing the general
knowledge, inference can be improved overall. Specialising the individual agents further
increases performance under the assumption of observations remaining the same (or similar)
for the diferent agents. In future work, we are interested in collaborative agents, able to request
support from others in case their own inference result is unsatisfactory. Instead of transmitting
all information or even raw input data, only intermediate results from the early exits are being
shared among the agents, reducing the amount of information transmitted while preserving
important privacy aspects.
[11] L. Esterle, J. N. A. Brown, I think therefore you are: Models for interaction in collectives
of self-aware cyber-physical systems, ACM Trans. on Cyber-Physical Systems 4 (2020).
[12] A. Diaconescu, K. L. Bellman, L. Esterle, H. Giese, S. Götz, P. Lewis, A. Zisman,
Architectures for collective self-aware computing systems, in: Self-Aware Computing Systems,
2017, pp. 191–235.
[13] L. Esterle, J. N. Brown, The competence awareness window: Knowing what i can and
cannot do, in: Int. Conf. on Autonomic Computing and Self-Organizing Systems, 2020, pp.
62–63.
[14] L. Esterle, Deep learning in multiagent systems, in: A. Iosifidis, A. Tefas (Eds.), Deep</p>
      <p>Learning for Robot Perception and Cognition, 2022, pp. 435–460.
[15] J. Konečny`, H. B. McMahan, F. X. Yu, P. Richtárik, A. T. Suresh, D. Bacon, Federated learning:</p>
      <p>Strategies for improving communication eficiency, arXiv preprint arXiv:1610.05492 (2016).
[16] S. Teerapittayanon, B. McDanel, H.-T. Kung, Branchynet: Fast inference via early exiting
from deep neural networks, in: Int. Conf. on Pattern Recognition, 2016, pp. 2464–2469.</p>
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