On Boolean Automata Networks (de)Composition1

2021 ◽  
Vol 181 (2-3) ◽  
pp. 163-188
Author(s):  
Kévin Perrot ◽  
Pacôme Perrotin ◽  
Sylvain Sené

Boolean automata networks (BANs) are a generalisation of Boolean cellular automata. In such, any theorem describing the way BANs compute information is a strong tool that can be applied to a wide range of models of computation. In this paper we explore a way of working with BANs which involves adding external inputs to the base model (via modules), and more importantly, a way to link networks together using the above mentioned inputs (via wirings). Our aim is to develop a powerful formalism for BAN (de)composition. We formulate three results: the first one shows that our modules/wirings definition is complete; the second one uses modules/wirings to prove simulation results amongst BANs; the final one expresses the complexity of the relation between modularity and the dynamics of modules.

2021 ◽  
Vol 11 (8) ◽  
pp. 3623
Author(s):  
Omar Said ◽  
Amr Tolba

Employment of the Internet of Things (IoT) technology in the healthcare field can contribute to recruiting heterogeneous medical devices and creating smart cooperation between them. This cooperation leads to an increase in the efficiency of the entire medical system, thus accelerating the diagnosis and curing of patients, in general, and rescuing critical cases in particular. In this paper, a large-scale IoT-enabled healthcare architecture is proposed. To achieve a wide range of communication between healthcare devices, not only are Internet coverage tools utilized but also satellites and high-altitude platforms (HAPs). In addition, the clustering idea is applied in the proposed architecture to facilitate its management. Moreover, healthcare data are prioritized into several levels of importance. Finally, NS3 is used to measure the performance of the proposed IoT-enabled healthcare architecture. The performance metrics are delay, energy consumption, packet loss, coverage tool usage, throughput, percentage of served users, and percentage of each exchanged data type. The simulation results demonstrate that the proposed IoT-enabled healthcare architecture outperforms the traditional healthcare architecture.


Author(s):  
Francisco González ◽  
Pierangelo Masarati ◽  
Javier Cuadrado ◽  
Miguel A. Naya

Formulating the dynamics equations of a mechanical system following a multibody dynamics approach often leads to a set of highly nonlinear differential-algebraic equations (DAEs). While this form of the equations of motion is suitable for a wide range of practical applications, in some cases it is necessary to have access to the linearized system dynamics. This is the case when stability and modal analyses are to be carried out; the definition of plant and system models for certain control algorithms and state estimators also requires a linear expression of the dynamics. A number of methods for the linearization of multibody dynamics can be found in the literature. They differ in both the approach that they follow to handle the equations of motion and the way in which they deliver their results, which in turn are determined by the selection of the generalized coordinates used to describe the mechanical system. This selection is closely related to the way in which the kinematic constraints of the system are treated. Three major approaches can be distinguished and used to categorize most of the linearization methods published so far. In this work, we demonstrate the properties of each approach in the linearization of systems in static equilibrium, illustrating them with the study of two representative examples.


2012 ◽  
Vol 23 (12) ◽  
pp. 1250085 ◽  
Author(s):  
ANDREW ADAMATZKY

Excitable cellular automata with dynamical excitation interval exhibit a wide range of space-time dynamics based on an interplay between propagating excitation patterns which modify excitability of the automaton cells. Such interactions leads to formation of standing domains of excitation, stationary waves and localized excitations. We analyzed morphological and generative diversities of the functions studied and characterized the functions with highest values of the diversities. Amongst other intriguing discoveries we found that upper boundary of excitation interval more significantly affects morphological diversity of configurations generated than lower boundary of the interval does and there is no match between functions which produce configurations of excitation with highest morphological diversity and configurations of interval boundaries with highest morphological diversity. Potential directions of future studies of excitable media with dynamically changing excitability may focus on relations of the automaton model with living excitable media, e.g. neural tissue and muscles, novel materials with memristive properties and networks of conductive polymers.


Author(s):  
Dilip Prasad

Windmilling requirements for aircraft engines often define propulsion and airframe design parameters. The present study is focused is on two key quantities of interest during windmill operation: fan rotational speed and stage losses. A model for the rotor exit flow is developed, that serves to bring out a similarity parameter for the fan rotational speed. Furthermore, the model shows that the spanwise flow profiles are independent of the throughflow, being determined solely by the configuration geometry. Interrogation of previous numerical simulations verifies the self-similar nature of the flow. The analysis also demonstrates that the vane inlet dynamic pressure is the appropriate scale for the stagnation pressure loss across the rotor and splitter. Examination of the simulation results for the stator reveals that the flow blockage resulting from the severely negative incidence that occurs at windmill remains constant across a wide range of mass flow rates. For a given throughflow rate, the velocity scale is then shown to be that associated with the unblocked vane exit area, leading naturally to the definition of a dynamic pressure scale for the stator stagnation pressure loss. The proposed scaling procedures for the component losses are applied to the flow configuration of Prasad and Lord (2010). Comparison of simulation results for the rotor-splitter and stator losses determined using these procedures indicates very good agreement. Analogous to the loss scaling, a procedure based on the fan speed similarity parameter is developed to determine the windmill rotational speed and is also found to be in good agreement with engine data. Thus, despite their simplicity, the methods developed here possess sufficient fidelity to be employed in design prediction models for aircraft propulsion systems.


1993 ◽  
Vol 1 (1) ◽  
pp. 3-9
Author(s):  
Heinz Riesenhuber

Thea purpose of science funding policy is to pave the way into new territory without knowing the final outcome to be expected. This needs the input of a wide range of scientific advice in response to well defined questions. There must be a serious intention to listen and if possible act on such advice.


1966 ◽  
Vol 112 (486) ◽  
pp. 471-484 ◽  
Author(s):  
Saul H. Rosenthal ◽  
Gerald L. Klerman

As currently used, the diagnosis of depression includes a wide range of clinical phenomena. This has not always been the case. Near the end of the 19th century, when the term depression began to evolve the meanings that it has today it was applied primarily to psychotics. The formulations of Freud in Mourning and Melancholia (1917), and of Kraepelin in Manic Depressive Insanity (1921) were based upon observations of patients who were both depressed and psychotic. In their work the contrast was between psychotic depression (or “melancholia”) on one hand, and normal sadness on the other. In the succeeding half-century, however, as psychiatry has extended its boundaries, increasing attention has been focused on non-psychotic depressions, often called “neurotic” or “reactive.” As these “neurotic” or “reactive” depressions reached public attention, a debate began over the way in which the depressive population should be described and the extent to which it should be subdivided. Critical and often sarcastic written battles were fought between the separatists and the unifiers during the 1920's and 1930's. These debates have been informatively chronicled by Partridge (1949). We have found it useful to divide these theorists into unifiers, dualists, and pluralists.


2018 ◽  
Vol 140 (12) ◽  
Author(s):  
Dilip Prasad

Windmilling requirements for aircraft engines often define propulsion and airframe design parameters. The present study is focused on two key quantities of interest during windmill operation: fan rotational speed and stage losses. A model for the rotor exit flow is developed that serves to bring out a similarity parameter for the fan rotational speed. Furthermore, the model shows that the spanwise flow profiles are independent of the throughflow, being determined solely by the configuration geometry. Interrogation of previous numerical simulations verifies the self-similar nature of the flow. The analysis also demonstrates that the vane inlet dynamic pressure is the appropriate scale for the stagnation pressure loss across the rotor and splitter. Examination of the simulation results for the stator reveals that the flow blockage resulting from the severely negative incidence that occurs at windmill remains constant across a wide range of mass flow rates. For a given throughflow rate, the velocity scale is then shown to be that associated with the unblocked vane exit area, leading naturally to the definition of a dynamic pressure scale for the stator stagnation pressure loss. The proposed scaling procedures for the component losses are applied to the flow configuration of Prasad and Lord (2010). Comparison of simulation results for the rotor-splitter and stator losses determined using these procedures indicates very good agreement. Analogous to the loss scaling, a procedure based on the fan speed similarity parameter is developed to determine the windmill rotational speed and is also found to be in good agreement with engine data. Thus, despite their simplicity, the methods developed here possess sufficient fidelity to be employed in design prediction models for aircraft propulsion systems.


Author(s):  
E. V. Mikhailovskaia ◽  
O. V. Sapunova

The article outlines the way the English system of punctuation marks is presented in contemporary ELT research and practice. The following types of sources are considered and analyzed in the article: grammar books for teaching English as the first, second or foreign language; reference books and web-sites aimed at preparing students for IELTS and TOEFL; books belonging to the genre known as popular science; purely scientific works on punctuation in general and the semicolon in particular. The main goals of the research are to reveal the central tendencies in teaching English punctuation on the example of the so-called weighty stops of vertical segmentation, namely the semicolon, and to see whether they manage to present a certain norm of using the stop. Thus, the present paper focuses on the semicolon one of the most controversial stops in the system, which has been proved to function both at the syntactic and stylistic levels. It is shown that a formal / grammatical approach is the most common way to treat punctuation in ELT literature; however, it does not take into account stylistic and prosodic peculiarities of the stops and thus fails to show the whole spectrum of its usage, as well as its phonetic and stylistic potential. Consequently, such an approach should not be applied to English one of the languages exhibiting a semantic-stylistic type of punctuation. It is proposed that the approach to be used in teaching English punctuation most effectively is pragmalinguistics, since it exploits a wide range of methods and means of analyzing a text, and also considers and highlights all the aspects of using the stops (their syntactic function, stylistic capacities and prosodic characteristics). Moreover, the article poses the question that the current methodology of the approach has to be further developed.


2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Ali Abbas ◽  
Bhawani Shankar Chowdhry ◽  
Muhammad Saqib ◽  
Vishal Dattana

The flying networks provide an efficient solution for a wide range of military and commercial purposes. The demand for portable and flexible communication is directed towards a quick growth in interaction among unmanned aerial vehicles (UAVs). Due to the frequent change in topology and high mobility of vehicles, routing and coordination becomes a challenging task. To maximize the throughput of the network, this study addresses the UAV swarm’s problems related to the coordination and routing and defines the proposed solution to solve these issues. For this, a network is assumed which contains an equal number of dynamic vehicles. It also presents the communication graph concept of UAVs and designs a fixed-wing UAV model to improve the efficiency of the network in terms of throughput. Furthermore, the proposed algorithm based on Cauchy particle swarm optimization (CPSO) aims towards the better performance of UAV swarms and aims to solve the combinatorial problem. The simulation results show and confirm the performance of the proposed algorithm.


2015 ◽  
Vol 3 (12) ◽  
pp. 1-186 ◽  
Author(s):  
Paul Roderick ◽  
Hugh Rayner ◽  
Sarah Tonkin-Crine ◽  
Ikumi Okamoto ◽  
Caroline Eyles ◽  
...  

BackgroundConservative kidney management (CKM) is recognised as an alternative to dialysis for a significant number of older adults with multimorbid stage 5 chronic kidney disease (CKD5). However, little is known about the way CKM is delivered or how it is perceived.AimTo determine the practice patterns for the CKM of older patients with CKD5, to inform service development and future research.Objectives(1) To describe the differences between renal units in the extent and nature of CKM, (2) to explore how decisions are made about treatment options for older patients with CKD5, (3) to explore clinicians’ willingness to randomise patients with CKD5 to CKM versus dialysis, (4) to describe the interface between renal units and primary care in managing CKD5 and (5) to identify the resources involved and potential costs of CKM.MethodsMixed-methods study. Interviews with 42 patients aged > 75 years with CKD5 and 60 renal unit staff in a purposive sample of nine UK renal units. Interviews informed the design of a survey to assess CKM practice, sent to all 71 UK units. Nineteen general practitioners (GPs) were interviewed concerning the referral of CKD patients to secondary care. We sought laboratory data on new CKD5 patients aged > 75 years to link with the nine renal units’ records to assess referral patterns.ResultsSixty-seven of 71 renal units completed the survey. Although terminology varied, there was general acceptance of the role of CKM. Only 52% of units were able to quantify the number of CKM patients. A wide range reflected varied interpretation of the designation ‘CKM’ by both staff and patients. It is used to characterise a future treatment option as well as non-dialysis care for end-stage kidney failure (i.e. a disease state equivalent to being on dialysis). The number of patients in the latter group on CKM was relatively small (median 8, interquartile range 4.5–22). Patients’ expectations of CKM and dialysis were strongly influenced by renal staff. In a minority of units, CKM was not discussed. When discussed, often only limited information about illness progression was provided. Staff wanted more research into the relative benefits of CKM versus dialysis. There was almost universal support for an observational methodology and a quarter would definitely be willing to participate in a randomised clinical trial, indicating that clinicians placed value on high-quality evidence to inform decision-making. Linked data indicated that most CKD5 patients were known to renal units. GPs expressed a need for guidance on when to refer older multimorbid patients with CKD5 to nephrology care. There was large variation in the scale and model of CKM delivery. In most, the CKM service was integrated within the service for all non-renal replacement therapy CKD5 patients. A few units provided dedicated CKM clinics and some had dedicated, modest funding for CKM.ConclusionsConservative kidney management is accepted across UK renal units but there is much variation in the way it is described and delivered. For best practice, and for CKM to be developed and systematised across all renal units in the UK, we recommend (1) a standard definition and terminology for CKM, (2) research to measure the relative benefits of CKM and dialysis and (3) development of evidence-based staff training and patient education interventions.FundingThe National Institute for Health Research Health Services and Delivery Research programme.


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