7,543 research outputs found
On Formal Consistency between Value and Coordination Models
In information systems (IS) engineering dierent techniques for modeling
inter-organizational collaborations are applied. In particular, value models
estimate the profitability for involved stakeholders, whereas coordination models
are used to agree upon the inter-organizational processes before implementing
them. During the execution of inter-organizational collaboration, in addition, event
logs are collected by the individual organizations representing another view of the
IS. The combination of the two models and the event log represent the IS and they
should therefore be consistent, i.e., not contradict each other. Since these models
are provided by dierent user groups during design time and the event log is
collected during run-time consistency is not straight forward. Inconsistency occurs
when models contain a conflicting description of the same information, i.e.,
there exists a conflicting overlap between the models. In this paper we introduce
an abstraction of value models, coordination models and event logs which allows
ensuring and maintaining alignment between models and event log. We demonstrate
its use by outlining a proof of an inconsistency resolution result based on
this abstraction. Thus, the introduction of abstractions allows to explore formal
inter-model relations based on consistency
Alignment between PIN1 Polarity and Microtubule Orientation in the Shoot Apical Meristem Reveals a Tight Coupling between Morphogenesis and Auxin Transport
Morphogenesis during multicellular development is regulated by intercellular signaling molecules as well as by the mechanical properties of individual cells. In particular, normal patterns of organogenesis in plants require coordination between growth direction and growth magnitude. How this is achieved remains unclear. Here we show that in Arabidopsis thaliana, auxin patterning and cellular growth are linked through a correlated pattern of auxin efflux carrier localization and cortical microtubule orientation. Our experiments reveal that both PIN1 localization and microtubule array orientation are likely to respond to a shared upstream regulator that appears to be biomechanical in nature. Lastly, through mathematical modeling we show that such a biophysical coupling could mediate the feedback loop between auxin and its transport that underlies plant phyllotaxis
History-sensitive versus future-sensitive approaches to security in distributed systems
We consider the use of aspect-oriented techniques as a flexible way to deal
with security policies in distributed systems. Recent work suggests to use
aspects for analysing the future behaviour of programs and to make access
control decisions based on this; this gives the flavour of dealing with
information flow rather than mere access control. We show in this paper that it
is beneficial to augment this approach with history-based components as is the
traditional approach in reference monitor-based approaches to mandatory access
control. Our developments are performed in an aspect-oriented coordination
language aiming to describe the Bell-LaPadula policy as elegantly as possible.
Furthermore, the resulting language has the capability of combining both
history- and future-sensitive policies, providing even more flexibility and
power.Comment: In Proceedings ICE 2010, arXiv:1010.530
Integral resource capacity planning for inpatient care services based on hourly bed census predictions
The design and operations of inpatient care facilities are typically largely historically shaped. A better match with the changing environment is often possible, and even inevitable due to the pressure on hospital budgets. Effectively organizing inpatient care requires simultaneous consideration of several interrelated planning issues. Also, coordination with upstream departments like the operating theater and the emergency department is much-needed. We present a generic analytical approach to predict bed census on nursing wards by hour, as a function of the Master Surgical Schedule (MSS) and arrival patterns of emergency patients. Along these predictions, insight is gained on the impact of strategic (i.e., case mix, care unit size, care unit partitioning), tactical (i.e., allocation of operating room time, misplacement rules), and operational decisions (i.e., time of admission/discharge). The method is used in the Academic Medical Center Amsterdam as a decision support tool in a complete redesign of the inpatient care operations
Data optimizations for constraint automata
Constraint automata (CA) constitute a coordination model based on finite
automata on infinite words. Originally introduced for modeling of coordinators,
an interesting new application of CAs is implementing coordinators (i.e.,
compiling CAs into executable code). Such an approach guarantees
correctness-by-construction and can even yield code that outperforms
hand-crafted code. The extent to which these two potential advantages
materialize depends on the smartness of CA-compilers and the existence of
proofs of their correctness.
Every transition in a CA is labeled by a "data constraint" that specifies an
atomic data-flow between coordinated processes as a first-order formula. At
run-time, compiler-generated code must handle data constraints as efficiently
as possible. In this paper, we present, and prove the correctness of two
optimization techniques for CA-compilers related to handling of data
constraints: a reduction to eliminate redundant variables and a translation
from (declarative) data constraints to (imperative) data commands expressed in
a small sequential language. Through experiments, we show that these
optimization techniques can have a positive impact on performance of generated
executable code
Identification of YdhV as the first molybdoenzyme binding a Bis-Mo-MPT cofactor in escherichia coli
The oxidoreductase YdhV in Escherichia coli has been predicted to belong to the family of molybdenum/tungsten cofactor (Moco/Wco)-containing enzymes. In this study, we characterized the YdhV protein in detail, which shares amino acid sequence homology with a tungsten-containing benzoyl-CoA reductase binding the bis-W-MPT (for metal-binding pterin) cofactor. The cofactor was identified to be of a bis-Mo-MPT type with no guanine nucleotides present, which represents a form of Moco that has not been found previously in any molybdoenzyme. Our studies showed that YdhV has a preference for bis-Mo-MPT over bis-W-MPT to be inserted into the enzyme. In-depth characterization of YdhV by X-ray absorption and electron paramagnetic resonance spectroscopies revealed that the bis-Mo-MPT cofactor in YdhV is redox active. The bis-Mo-MPT and bis-W-MPT cofactors include metal centers that bind the four sulfurs from the two dithiolene groups in addition to a cysteine and likely a sulfido ligand. The unexpected presence of a bis-Mo-MPT cofactor opens an additional route for cofactor biosynthesis in E. coli and expands the canon of the structurally highly versatile molybdenum and tungsten cofactors
The Plurality of Daily Digital Health: The Emergence of a New Form of Health Coordination
This article presents the current datafication processes in the field of health as a new form of health coordination. Methodologically, the conceptual foundation of the article is embedded in neopragmatist thinking and mainly informed by the "economics of convention" (EC). At the beginning, it is made clear that the datafication processes in the health system and in people's everyday lives are primarily a future vision that has high hopes for improving and controlling health. The aim of the article is to analyze the current effects of these mobilization processes and to show that with datafication processes, a new coordination mode of a digital daily health is introduced. To this end, the new form of digital daily health is being introduced. For this purpose, its characteristics are described and its relevance for coordination processes is shown. After that, the intersection between the new form of digital daily health and individual health will be analyzed. Finally, the consequences of this new health coordination form will be shown on an individual level as well as on the level of political economy of health
The Impact of Coordination Quality on Coordination Dynamics and Team Performance: When Humans Team with Autonomy
abstract: This increasing role of highly automated and intelligent systems as team members has started a paradigm shift from human-human teaming to Human-Autonomy Teaming (HAT). However, moving from human-human teaming to HAT is challenging. Teamwork requires skills that are often missing in robots and synthetic agents. It is possible that adding a synthetic agent as a team member may lead teams to demonstrate different coordination patterns resulting in differences in team cognition and ultimately team effectiveness. The theory of Interactive Team Cognition (ITC) emphasizes the importance of team interaction behaviors over the collection of individual knowledge. In this dissertation, Nonlinear Dynamical Methods (NDMs) were applied to capture characteristics of overall team coordination and communication behaviors. The findings supported the hypothesis that coordination stability is related to team performance in a nonlinear manner with optimal performance associated with moderate stability coupled with flexibility. Thus, we need to build mechanisms in HATs to demonstrate moderately stable and flexible coordination behavior to achieve team-level goals under routine and novel task conditions.Dissertation/ThesisDoctoral Dissertation Engineering 201
Metacognition and Reflection by Interdisciplinary Experts: Insights from Cognitive Science and Philosophy
Interdisciplinary understanding requires integration of insights from
different perspectives, yet it appears questionable whether disciplinary experts
are well prepared for this. Indeed, psychological and cognitive scientific studies
suggest that expertise can be disadvantageous because experts are often more biased
than non-experts, for example, or fixed on certain approaches, and less flexible in
novel situations or situations outside their domain of expertise. An explanation is
that experts’ conscious and unconscious cognition and behavior depend upon their
learning and acquisition of a set of mental representations or knowledge structures.
Compared to beginners in a field, experts have assembled a much larger set of
representations that are also more complex, facilitating fast and adequate perception
in responding to relevant situations. This article argues how metacognition should be
employed in order to mitigate such disadvantages of expertise: By metacognitively
monitoring and regulating their own cognitive processes and representations,
experts can prepare themselves for interdisciplinary understanding. Interdisciplinary
collaboration is further facilitated by team metacognition about the team, tasks,
process, goals, and representations developed in the team. Drawing attention to
the need for metacognition, the article explains how philosophical reflection on the
assumptions involved in different disciplinary perspectives must also be considered
in a process complementary to metacognition and not completely overlapping with
it. (Disciplinary assumptions are here understood as determining and constraining
how the complex mental representations of experts are chunked and structured.) The
article concludes with a brief reflection on how the process of Reflective Equilibrium
should be added to the processes of metacognition and philosophical reflection in
order for experts involved in interdisciplinary collaboration to reach a justifiable
and coherent form of interdisciplinary integration. An Appendix of “Prompts or
Questions for Metacognition” that can elicit metacognitive knowledge, monitoring,
or regulation in individuals or teams is included at the end of the article
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