Mobile Objects as Mobile Processes

Obliq is a lexically-scoped, distributed, object-based programming language. In Obliq, the migration of an object is proposed as creating a clone of the object at the target site, whereafter the original object is turned into an alias for the clone. Obliq has only an informal semantics, so there is no proof that this style of migration is safe i.e., transparent to object clients In previous work, we introduced Ojeblik, an abstraction of~Obliq, where, by lexical scoping sites have been abstracted away. We used Ojeblik in order to exhibit how the semantics behind Obliq's implementation renders migration unsafe. We also suggested a modified semantics that we conjectured instead to be safe. In this paper, we rewrite our modified semantics of \OBLIQ\ in terms of the pi-calculus, and we use it to formally prove the correctness of object surrogation, the abstraction of object migration in Ojebli

Theorization and translation in information technology institutionalization: evidence from Danish home care

Although institutional theory has become a more dominant perspective in information systems research, studies have only paid scant attention to how field dynamics and organizational processes coevolve during information technology institutionalization. Against this backdrop, we present a new conceptualization based on the “traveling of ideas” metaphor that distinguishes between theorization of ideas about IT usage across an organizational field and translation of such ideas into practical use of IT within particular organizations. Drawing on these distinct analytical views, we posit that IT institutionalization is constituted through recursive intertwining of theorization and translation involving both linguistic and material objects. To illustrate the detailed workings of this conceptualization, we apply it to a longitudinal study of mobile IT institutionalization within Danish home care. We demonstrate how heterogeneous actors within the Danish home care field theorized ideas about mobile IT usage and how these ideas translated into different local arrangements. Further, our account reveals a complex institutionalization process in which mobile IT was first seen as a fashionable recipe for improvement but subsequently became the subject of controversy. The paper adds to the emerging process and discourse literature on IT institutionalization by shedding new light on how IT ideas travel across a field and within individual organizations, how they transform and become legitimized over time, and how they take on different linguistic and material forms across organizational settings

An Autonomous Distributed Fault-Tolerant Local Positioning System

We describe a fault-tolerant, GPS-independent (Global Positioning System) distributed autonomous positioning system for static/mobile objects and present solutions for providing highly-accurate geo-location data for the static/mobile objects in dynamic environments. The reliability and accuracy of a positioning system fundamentally depends on two factors; its timeliness in broadcasting signals and the knowledge of its geometry, i.e., locations and distances of the beacons. Existing distributed positioning systems either synchronize to a common external source like GPS or establish their own time synchrony using a scheme similar to a master-slave by designating a particular beacon as the master and other beacons synchronize to it, resulting in a single point of failure. Another drawback of existing positioning systems is their lack of addressing various fault manifestations, in particular, communication link failures, which, as in wireless networks, are increasingly dominating the process failures and are typically transient and mobile, in the sense that they typically affect different messages to/from different processes over time

Contingent task and motion planning under uncertainty for human–robot interactions

Manipulation planning under incomplete information is a highly challenging task for mobile manipulators. Uncertainty can be resolved by robot perception modules or using human knowledge in the execution process. Human operators can also collaborate with robots for the execution of some difficult actions or as helpers in sharing the task knowledge. In this scope, a contingent-based task and motion planning is proposed taking into account robot uncertainty and human–robot interactions, resulting a tree-shaped set of geometrically feasible plans. Different sorts of geometric reasoning processes are embedded inside the planner to cope with task constraints like detecting occluding objects when a robot needs to grasp an object. The proposal has been evaluated with different challenging scenarios in simulation and a real environment.Postprint (published version

Exclusion and Object Tracking in a Network of Processes

This paper concerns two fundamental problems in distributed computing---mutual exclusion and mobile object tracking. For a variant of the mutual exclusion problem where the network topology is taken into account, all existing distributed solutions make use of tokens. It turns out that these token-based solutions for mutual exclusion can also be adapted for object tracking, as the token behaves very much like a mobile object. To handle objects with replication, we go further to consider the more general $k$-exclusion problem which has not been as well studied in a network setting. A strong fairness property for $k$-exclusion requires that a process trying to enter the critical section will eventually succeed even if \emph{up to} $k-1$ processes stay in the critical section indefinitely. We present a comparative survey of existing token-based mutual exclusion algorithms, which have provided much inspiration for later $k$-exclusion algorithms. We then propose two solutions to the $k$-exclusion problem, the second of which meets the strong fairness requirement. Fault-tolerance issues are also discussed along with the suggestion of a third algorithm that is also strongly fair. Performances of the three algorithms are compared by simulation. Finally, we show how the various exclusion algorithms can be adapted for tracking mobile objects

Towards a Semantic Gas Source Localization under Uncertainty

Towards a Semantic Gas Source Localization under Uncertainty.Communications in Computer and Information Science book series (CCIS, volume 855), doi:10.1007/978-3-319-91479-4_42This work addresses the problem of efficiently and coherently locating a gas source in a domestic environment with a mobile robot, meaning efficiently the coverage of the shortest distance as possible and coherently the consideration of different gas sources explaining the gas presence. The main contribution is the exploitation, for the first time, of semantic relationships between the gases detected and the objects present in the environment to face this challenging issue. Our proposal also takes into account both the uncertainty inherent in the gas classification and object recognition processes. These uncertainties are combined through a probabilistic Bayesian framework to provide a priority-ordered list of (previously observed) objects to check. Moreover the proximity of the different candidates to the current robot location is also considered by a cost function, which output is used for planning the robot inspection path. We have conducted an initial demonstration of the suitability of our gas source localization approach by simulating this task within domestic environments for a variable number of objects, and comparing it with an greedy approach.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Framing the Mobile Phone: The Psychopathologies of an Everyday Object

This article proposes that the affective processes that shape our relationship to the world of digital consumption and communication can be illuminated further when viewed through a lens of object relations psychoanalysis. We focus on the use of the mobile phone as both an object in the world and of the psyche in order to reflect upon its uses as an evocative object that shapes the psychosocial boundaries of experience in everyday life. We argue that in contrast to the concepts of interpersonal communication that can be found in some domains of popular culture and in communication studies, object relations psychoanalysis can be usefully deployed in order to explore the unconscious attachments that develop in relation to consumer objects, allowing for the complexity of feeling and reflection that may emerge in relation to them and the potential spaces of the mind. The mobile phone’s routine uses and characteristics are widely understood. At the same time, the mobile phone invites critical reflections that identify a paradoxical object of both creative and pathological use. Such reflexivity includes the mobile’s relationship to the complexity of psychosocial experience within the contemporary cultural moment. Applying the ideas of psychoanalysts Donald Winnicott, Thomas Ogden and Christopher Bollas, we argue that one explanation for why the mobile phone continues to attract not only enthusiastic cultural commentary but also a degree of apprehension across academic and popular-discursive settings can be found in its capacity to both disrupt and connect as an object of attachment and as a means of unconscious escap