scholarly journals Multi-scale verification of distributed synchronisation

2020 ◽  
Vol 55 (3) ◽  
pp. 171-221
Author(s):  
Paul Gainer ◽  
Sven Linker ◽  
Clare Dixon ◽  
Ullrich Hustadt ◽  
Michael Fisher
Keyword(s):  
Distributed Systems ◽  
Coupled Oscillators ◽  
Population Based ◽  
Levels Of Abstraction ◽  
Biologically Inspired ◽  
Collective Models ◽  
Multi Scale ◽  
Pulse Coupled Oscillators ◽  
The Individual ◽  
Different Levels

AbstractAlgorithms for the synchronisation of clocks across networks are both common and important within distributed systems. We here address not only the formal modelling of these algorithms, but also the formal verification of their behaviour. Of particular importance is the strong link between the very different levels of abstraction at which the algorithms may be verified. Our contribution is primarily the formalisation of this connection between individual models and population-based models, and the subsequent verification that is then possible. While the technique is applicable across a range of synchronisation algorithms, we particularly focus on the synchronisation of (biologically-inspired) pulse-coupled oscillators, a widely used approach in practical distributed systems. For this application domain, different levels of abstraction are crucial: models based on the behaviour of an individual process are able to capture the details of distinguished nodes in possibly heterogenous networks, where each node may exhibit different behaviour. On the other hand, collective models assume homogeneous sets of processes, and allow the behaviour of the network to be analysed at the global level. System-wide parameters may be easily adjusted, for example environmental factors inhibiting the reliability of the shared communication medium. This work provides a formal bridge across the “abstraction gap” separating the individual models and the population-based models for this important class of synchronisation algorithms.

Implications of Person Fluctuation for the Stability and Validity of Test Scores

Methodology ◽  
2006 ◽  
Vol 2 (4) ◽  
pp. 142-148 ◽  
Author(s):  
Pere J. Ferrando
Keyword(s):  
Item Response ◽  
Test Scores ◽  
Temporal Stability ◽  
Person Fit ◽  
Item Parameters ◽  
Individual Trait ◽  
The Stability ◽  
The Individual ◽  
Different Levels ◽  
Fluctuation Model

In the IRT person-fluctuation model, the individual trait levels fluctuate within a single test administration whereas the items have fixed locations. This article studies the relations between the person and item parameters of this model and two central properties of item and test scores: temporal stability and external validity. For temporal stability, formulas are derived for predicting and interpreting item response changes in a test-retest situation on the basis of the individual fluctuations. As for validity, formulas are derived for obtaining disattenuated estimates and for predicting changes in validity in groups with different levels of fluctuation. These latter formulas are related to previous research in the person-fit domain. The results obtained and the relations discussed are illustrated with an empirical example.

Value-driven issues throughout the development of sociological theory

2020 ◽  
pp. 147-160
Author(s):  
Gulbarshyn Chepurko ◽  
Valerii Pylypenko
Keyword(s):  
Social Interactions ◽  
Social System ◽  
Sociological Theory ◽  
Social Scientists ◽  
Social Sphere ◽  
Technological Advances ◽  
The Social ◽  
The Individual ◽  
Different Levels

The paper examines and compares how the major sociological theories treat axiological issues. Value-driven topics are analysed in view of their relevance to society in times of crisis, when both societal life and the very structure of society undergo dramatic change. Nowadays, social scientists around the world are also witnessing such a change due to the emergence of alternative schools of sociological thought (non-classical, interpretive, postmodern, etc.) and, subsequently, the necessity to revise the paradigms that have been existed in sociology so far. Since the above-mentioned approaches are often used to address value-related issues, building a solid theoretical framework for these studies takes on considerable significance. Furthermore, the paradigm revision has been prompted by technological advances changing all areas of people’s lives, especially social interactions. The global human community, integral in nature, is being formed, and production of human values now matters more than production of things; hence the “expansion” of value-focused perspectives in contemporary sociology. The authors give special attention to collectivities which are higher-order units of the social system. These units are described as well-organised action systems where each individual performs his/her specific role. Just as the role of an individual is distinct from that of the collectivity (because the individual and the collectivity are different as units), so too a distinction is drawn between the value and the norm — because they represent different levels of social relationships. Values are the main connecting element between the society’s cultural system and the social sphere while norms, for the most part, belong to the social system. Values serve primarily to maintain the pattern according to which the society is functioning at a given time; norms are essential to social integration. Apart from being the means of regulating social processes and relationships, norms embody the “principles” that can be applied beyond a particular social system. The authors underline that it is important for Ukrainian sociology to keep abreast of the latest developments in the field of axiology and make good use of those ideas because this is a prerequisite for its successful integration into the global sociological community.

Differentiation of endemic areas by incidence rates of tick-borne infectious diseases as the basis for choosing prevention strategy and tactics

2019 ◽  
pp. 56-61
Author(s):  
N.V. Rudakov ◽  
N.A. Penyevskaya ◽  
D.A. Saveliev ◽  
S.A. Rudakova ◽  
C.V. Shtrek ◽  
...  
Keyword(s):  
High Risk ◽  
Infectious Diseases ◽  
Population Based ◽  
Preventive Therapy ◽  
Incidence Rates ◽  
Prevention Strategy ◽  
Individual Risk ◽  
The Individual ◽  
Integral Assessment ◽  
Very High

Research objective. Differentiation of natural focal areas of Western Siberia by integral incidence rates of tick-borne infectious diseases for determination of the strategy and tactics of their comprehensive prevention. Materials and methods. A retrospective analysis of official statistics for the period 2002-2018 for eight sub-federal units in the context of administrative territories was carried out. The criteria of differentiation were determined by means of three evaluation scales, including long-term mean rates of tick-borne encephalitis, tick-borne borreliosis, and Siberian tick-borne typhus. As a scale gradation tool, we used the number of sample elements between the confidence boundaries of the median. The integral assessment was carried out by the sum of points corresponding to the incidence rates for each of the analyzed infections. Results. The areas of low, medium, above average, high and very high risk of tick-borne infectious diseases were determined. Recommendations on the choice of prevention strategy and tactics were given. In areas of very high and high incidence rates, a combination of population-based and individual prevention strategies is preferable while in other areas a combination of high-risk and individual strategies is recommended. Discussion. Epidemiologic zoning should be the basis of a risk-based approach to determining optimal volumes and directions of preventive measures against natural focal infections. It is necessary to improve the means and methods of determining the individual risk of getting infected and developing tick-borne infectious diseases in case of bites, in view of mixed infection of vectors, as well as methods of post-exposure disease prevention (preventive therapy).

scholarly journals Circulating bioactive sclerostin levels in an Austrian population-based cohort

2021 ◽  
Author(s):  
Katharina Kerschan-Schindl ◽  
Ursula Föger-Samwald ◽  
Andreas Gleiss ◽  
Stefan Kudlacek ◽  
Jacqueline Wallwitz ◽  
...  
Keyword(s):  
Serum Levels ◽  
Population Based ◽  
Negative Regulator ◽  
Total Serum ◽  
Mineral Density ◽  
Cross Sectional ◽  
Robust Parameter ◽  
Austrian Population ◽  
Different Levels

Summary Background Circulating serum sclerostin levels are supposed to give a good estimation of the levels of this negative regulator of bone mass within bone. Most studies evaluating total serum sclerostin found different levels in males compared to females and in older compared to younger subjects. Besides an ELISA detecting total sclerostin an ELISA determining bioactive sclerostin has been developed. The aim of this study was to investigate serum levels of bioactive sclerostin in an Austrian population-based cohort. Methods We conducted a cross-sectional observational study in 235 healthy subjects. Using the bioactive ELISA assay (Biomedica) bioactive sclerostin levels were evaluated. Results Serum levels of bioactive sclerostin were higher in men than in women (24%). The levels correlated positively with age (r = 0.47). A positive correlation could also be detected with body mass index and bone mineral density. Conclusion Using the ELISA detecting bioactive sclerostin our results are consistent with data in the literature obtained by different sclerostin assays. The determination of sclerostin concentrations in peripheral blood thus appears to be a robust parameter of bone metabolism.

The Need for Personalized Risk-Stratified Approaches to Treatment for Gestational Diabetes: A Narrative Review

2021 ◽  
Author(s):  
Shamil D. Cooray ◽  
Jacqueline A. Boyle ◽  
Georgia Soldatos ◽  
Shakila Thangaratinam ◽  
Helena J. Teede
Keyword(s):  
Gestational Diabetes ◽  
Pregnancy Outcomes ◽  
Population Based ◽  
Adverse Pregnancy Outcomes ◽  
Therapeutic Interventions ◽  
Clinical Prediction Model ◽  
Increased Risk ◽  
Adverse Pregnancy ◽  
The Individual ◽  
Personalized Risk

AbstractGestational diabetes mellitus (GDM) is common and is associated with an increased risk of adverse pregnancy outcomes. However, the prevailing one-size-fits-all approach that treats all women with GDM as having equivalent risk needs revision, given the clinical heterogeneity of GDM, the limitations of a population-based approach to risk, and the need to move beyond a glucocentric focus to address other intersecting risk factors. To address these challenges, we propose using a clinical prediction model for adverse pregnancy outcomes to guide risk-stratified approaches to treatment tailored to the individual needs of women with GDM. This will allow preventative and therapeutic interventions to be delivered to those who will maximally benefit, sparing expense, and harm for those at a lower risk.

Embodying the culture of achievement: Culture between illness and perfection is a ‘thin line’ – obtaining the ideal female body as an act of achievement

2021 ◽  
pp. 1354067X2110040
Author(s):  
Josefine Dilling ◽  
Anders Petersen
Keyword(s):  
Experimental Study ◽  
Human Body ◽  
Female Body ◽  
The Body ◽  
Thin Line ◽  
Complex Processes ◽  
The Individual ◽  
Different Levels ◽  
The Ideal ◽  
Body Ideals

In this article, we argue that certain behaviour connected to the attempt to attain contemporary female body ideals in Denmark can be understood as an act of achievement and, thus, as an embodiment of the culture of achievement, as it is characterised in Præstationssamfundet, written by the Danish sociologist Anders Petersen (2016) Hans Reitzels Forlag . Arguing from cultural psychological and sociological standpoints, this article examines how the human body functions as a mediational tool in different ways from which the individual communicates both moral and aesthetic sociocultural ideals and values. Complex processes of embodiment, we argue, can be described with different levels of internalisation, externalisation and materialisation, where the body functions as a central mediator. Analysing the findings from a qualitative experimental study on contemporary body ideals carried out by the Danish psychologists Josefine Dilling and Maja Trillingsgaard, this article seeks to anchor such theoretical claims in central empirical findings. The main conclusions from the study are used to structure the article and build arguments on how expectations and ideals expressed in an achievement society become embodied.

scholarly journals Model-Driven Architectural Framework towards Safe and Secure Nuclear Power Reactors

Sensors ◽  
2021 ◽  
Vol 21 (15) ◽  
pp. 5136
Author(s):  
Bassem Ouni ◽  
Christophe Aussagues ◽  
Saadia Dhouib ◽  
Chokri Mraidha
Keyword(s):  
Nuclear Power ◽  
Nuclear Reactors ◽  
System Development ◽  
Levels Of Abstraction ◽  
Model Driven ◽  
Case System ◽  
Architectural Framework ◽  
Performance Check ◽  
High Level ◽  
Different Levels

Sensor-based digital systems for Instrumentation and Control (I&C) of nuclear reactors are quite complex in terms of architecture and functionalities. A high-level framework is highly required to pre-evaluate the system’s performance, check the consistency between different levels of abstraction and address the concerns of various stakeholders. In this work, we integrate the development process of I&C systems and the involvement of stakeholders within a model-driven methodology. The proposed approach introduces a new architectural framework that defines various concepts, allowing system implementations and encompassing different development phases, all actors, and system concerns. In addition, we define a new I&C Modeling Language (ICML) and a set of methodological rules needed to build different architectural framework views. To illustrate this methodology, we extend the specific use of an open-source system engineering tool, named Eclipse Papyrus, to carry out many automation and verification steps at different levels of abstraction. The architectural framework modeling capabilities will be validated using a realistic use case system for the protection of nuclear reactors. The proposed framework is able to reduce the overall system development cost by improving links between different specification tasks and providing a high abstraction level of system components.

Biologically inspired motion synthesis method of two-legged robot with compliant feet

Robotica ◽  
2011 ◽  
Vol 29 (7) ◽  
pp. 1049-1057 ◽  
Author(s):  
Teresa Zielinska ◽  
Andrzej Chmielniak
Keyword(s):  
Central Pattern Generator ◽  
Coupled Oscillators ◽  
Synthesis Method ◽  
Pattern Generator ◽  
Experimental Results ◽  
Human Gait ◽  
Legged Robot ◽  
Biologically Inspired ◽  
Reference Pattern ◽  
Periodic Signals

SUMMARYThis work presents biologically inspired method of gait generation. It uses the reference to the periodic signals generated by biological central pattern generator. The coupled oscillators with correction functions are used to produce leg joint trajectories. The human gait is the reference pattern. The features of generated gait are compared to the human walk. The spring-loaded foot design is presented together with experimental results.

Sign in / Sign up

Export Citation Format

Share Document