scholarly journals POLYCHRONY for System Design

2003 ◽  
Vol 12 (03) ◽  
pp. 261-303 ◽  
Author(s):  
Paul Le Guernic ◽  
Jean-Pierre Talpin ◽  
Jean-Christophe Le Lann
Keyword(s):  
Mathematical Model ◽  
Integrated Circuits ◽  
System Design ◽  
Point Of View ◽  
Relational Model ◽  
Signal Design ◽  
Synchronous Circuits ◽  
Design Language ◽  
Complex Architectures ◽  
High Level

Rising complexities and performances of integrated circuits and systems, shortening time-to-market demands for electronic equipments, growing installed bases of intellectual property (IP), requirements for adapting existing IP blocks with new services, all stress high-level design as a prominent research topic and call for the development of appropriate methodological solutions. In this aim, system design based on the so-called "synchronous hypothesis" consists of abstracting the nonfunctional implementation details of a system and lets one benefit from a focused reasoning on the logics behind the instants at which the system functionalities should be secured. With this point of view, synchronous design models and languages provide intuitive (ontological) models for integrated circuits. This affinity explains the ease of generating synchronous circuits and verify their functionalities using compilers and related tools that implement this approach. In the relational mathematical model behind the design language SIGNAL, this affinity goes beyond the domain of purely synchronous circuits, and embraces the context of complex architectures consisting of synchronous circuits and desynchronization protocols: globally asynchronous and locally synchronous architectures (GALS). The unique features of the relational model behind SIGNAL are to provide the notion of polychrony: the capability to describe circuits and systems with several clocks; and to support refinement: the ability to assist and support system design from the early stages of requirement specification, to the later stages of synthesis and deployment. The SIGNAL model provides a design methodology that forms a continuum from synchrony to asynchrony, from specification to implementation, from abstraction to concretization, from interfaces to implementations. SIGNAL gives the opportunity to seamlessly model circuits and devices at multiple levels of abstractions, by implementing mechanisms found in many hardware simulators, while reasoning within a simple and formally defined mathematical model. In the same manner, the flexibility inherent to the abstract notion of signal, handled in the synchronous-desynchronized design model of SIGNAL, invites and favors the design of correct by construction systems by means of well-defined transformations of system specifications (morphisms) that preserve the intended semantics and stated properties of the architecture under design. The aim of the present article is to review and summarize these formal, correct-by-construction, design transformations. Most of them are implemented in the POLYCHRONY tool-set, allowing for a mixed bottom–up and top–down design of an embedded hardware–software system using the SIGNAL design language.

scholarly journals The Growth of The Anti-Jewish Stereotype

1985 ◽  
Vol 30 (3) ◽  
pp. 270-306 ◽  
Author(s):  
Dik Van Arkel ◽  
M. W. H. Schreuder
Keyword(s):  
Mathematical Model ◽  
Source Material ◽  
Point Of View ◽  
The Past ◽  
Extensive Test ◽  
Anti Jewish ◽  
High Level ◽  
Historical Model ◽  
True Activity ◽  
Narrative Element

There are three good reasons at the present time to try to arrive at an historical model to explain the development of anti-Jewish stereotyping and prejudice, and in this way, provided it is worked out at a sufficiently high level of abstraction, at an historical model of racism.Thefirstreason is that both the Netherlands and its neighbours are increasingly faced with racism and that for a good line of action it is necessary to collect all kinds of knowledge. Moreover, it is desirable that historians prove willing to co-operate by making their particular contribution to this collection of knowledge. Thesecondreason is that in contemporary thinking about history a tendency seems to have made itself felt that considers the narrative element of history as the only true activity of the historian, so that a hypothetical-deductive, one might say Popperian, approach to the past seems to be wrong. Although I do not want to enter into a methodological discussion, which I am glad to leave to my friend P. H. H. Vries, who has very capably formulated a point of view that I subscribe to, my intention is to show the usefulness of an abstract, partially mathematical, model in this article. By the way, in the framework of an article it is impossible to present an extensive test of the predictions of the model by means of source material. It can only be hinted at. This article is not non-narrative because I want it to be non-narrative, but because of lack of space. A full exposition would need a book. I shall only present in summary what I hope is the logical argument that lies at the basis of the model.

scholarly journals Design automation of ΔΣ switched capacitor modulators using spice and MATLAB

2014 ◽  
Vol 11 (1) ◽  
pp. 47-59
Author(s):  
Dejan Mirkovic ◽  
Predrag Petkovic
Keyword(s):  
Integrated Circuits ◽  
Design Automation ◽  
Low Cost ◽  
Signal Design ◽  
Time Saving ◽  
Mixed Signal ◽  
Working Environments ◽  
High Level ◽  
Technology Processes ◽  
Simulation Time

Concerning the fact that the design of contemporary integrated circuits (IC) is practically impossible without using sophisticated Electronic Design Automation (EDA) software, this paper gives some interesting thoughts and considerations about that issue. As technology processes advances on year basis consequently EDA industry is forced to follow this trend as well. This, on the other hand, requires IC designer to frequently and efficiently accommodate to new working environments. Authors of this paper suggest a method for high level circuit analysis that is based on using common (open source or low cost) circuit simulators but precise and fast enough to meet requirements imposed by demanding mixed-signal blocks. The paper demonstrates the proposed EDA procedure on an example of second order ?? modulator design. It illustrates considerable simulation time saving which is more than welcome in a world of analogue and mixed-signal design.

Mathematical Model and Algorithm to Optimize the Construction of Adjustable Multi-Axis Heads

2013 ◽  
Vol 371 ◽  
pp. 617-621
Author(s):  
Eduard Niţu ◽  
Alexandru Babă ◽  
Monica Iordache ◽  
Aurel Costea ◽  
Doina Iacomi
Keyword(s):  
Mathematical Model ◽  
Manufacturing Systems ◽  
Computing Methods ◽  
Point Of View ◽  
Paper Study ◽  
Current Trends ◽  
High Level ◽  
Technical Solutions ◽  
Modular Structures ◽  
Adaptation Costs

Current trends in the field of manufacturing systems are mostly connected to the transfer of technical solutions specific to large manufacturing series toward small and medium manufacturing series. Our researches presented in this paper study thoroughly and expand the concept of modularization of multi-tool processing devices in order to obtain a high level of productivity and flexibility of the technological system, as well as a significant decrease of the adaptation costs. To this end, we elaborated and used computing methods, mathematical models, optimizing algorithms and original constructive solutions to develop new modular structures meant to optimize the construction and configuration of adjustable multi-spindle ends. We obtained the highest level of modularization for this type of equipment which integrates from the point of view of organs and is functional from the point of view of performance, highly efficient, in a flexible complex multi-tool system of simultaneous-successive and multi-directional processing.

Territorial Distribution of Alcohol and Drug Addictions Mortality Concerning Regional Disparities in the Slovak Republic from Year 1996 to Year 2015

2020 ◽  
Keyword(s):  
Mortality Rate ◽  
Slovak Republic ◽  
Regional Disparities ◽  
Point Of View ◽  
Extreme Position ◽  
Data Set ◽  
Female Sex ◽  
Male Sex ◽  
The Individual ◽  
High Level

BACKGROUND: This paper deals with territorial distribution of the alcohol and drug addictions mortality at a level of the districts of the Slovak Republic. AIM: The aim of the paper is to explore the relations within the administrative territorial division of the Slovak Republic, that is, between the individual districts and hence, to reveal possibly hidden relation in alcohol and drug mortality. METHODS: The analysis is divided and executed into the two fragments – one belongs to the female sex, the other one belongs to the male sex. The standardised mortality rate is computed according to a sequence of the mathematical relations. The Euclidean distance is employed to compute the similarity within each pair of a whole data set. The cluster analysis examines is performed. The clusters are created by means of the mutual distances of the districts. The data is collected from the database of the Statistical Office of the Slovak Republic for all the districts of the Slovak Republic. The covered time span begins in the year 1996 and ends in the year 2015. RESULTS: The most substantial point is that the Slovak Republic possesses the regional disparities in a field of mortality expressed by the standardised mortality rate computed particularly for the diagnoses assigned to the alcohol and drug addictions at a considerably high level. However, the female sex and the male sex have the different outcome. The Bratislava III District keeps absolutely the most extreme position. It forms an own cluster for the both sexes too. The Topoľčany District bears a similar extreme position from a point of view of the male sex. All the Bratislava districts keep their mutual notable dissimilarity. Contrariwise, evaluation of a development of the regional disparities among the districts looks like notably heterogeneously. CONCLUSIONS: There are considerable regional discrepancies throughout the districts of the Slovak Republic. Hence, it is necessary to create a common platform how to proceed with the solution of this issue.

On the displacements of the contours of the optic-electronic space images. Mathematical modeling of displacement

2017 ◽  
Vol 992 (4) ◽  
pp. 32-38 ◽  
Author(s):  
E.G. Voronin
Keyword(s):  
Mathematical Modeling ◽  
Remote Sensing ◽  
Mathematical Model ◽  
Point Of View ◽  
Design Features ◽  
Space Images ◽  
Electronic Imaging ◽  
Measuring Accuracy ◽  
Physical Laws

The article opens a cycle of three consecutive publications dedicated to the phenomenon of the displacement of the same points in overlapping scans obtained adjacent CCD matrices with opto-electronic imagery. This phenomenon was noticed by other authors, but the proposed explanation for the origin of displacements and the resulting estimates are insufficient, and developed their solutions seem controversial from the point of view of recovery of the measuring accuracy of opticalelectronic space images, determined by the physical laws of their formation. In the first article the mathematical modeling of the expected displacements based on the design features of a scanning opto-electronic imaging equipment. It is shown that actual bias cannot be forecast, because they include additional terms, which may be gross, systematic and random values. The proposed algorithm for computing the most probable values of the additional displacement and ways to address some of the systematic components of these displacements in a mathematical model of optical-electronic remote sensing.

Arising of Informal Women's Learn-to-code Communities

2021 ◽  
Vol 21 (2) ◽  
pp. 1-24
Author(s):  
Louise Ann Lyon ◽  
Chelsea Clayton
Keyword(s):  
Learning Community ◽  
Virtual Communities ◽  
Point Of View ◽  
Customer Relationship ◽  
Activity System ◽  
Learning Group ◽  
Management Platform ◽  
High Level ◽  
Verbal Encouragement ◽  
Activity Systems Analysis

Female-focused, grassroots communities purporting to help women learn to code are popping up in a variety of settings, indicating the motivation on the part of the participants to evade male-dominated settings while learning. However, little is known about how these groups function as an activity system. With current technology enabling the forming of virtual communities and the meteoric rise in use of the Salesforce CRM (customer relationship management) platform, a group of women have formed a coaching and learning community designed to help women move from Salesforce administrators to software developers through learning to code. We used activity systems analysis (ASA) to investigate this real-world instance of the larger phenomenon using an ethnographic approach. We used ASA to organize and make sense of the data by first creating a table listing the points on the activity system triangle (subject, rules, object, etc.) and filling in the points of the triangle based on the design of the coaching and learning group as described by participants; this gave us a high-level view of the activity system. To understand the subjects’ point of view of the system, we then created a new column in the table to fill in themes that emerged from our qualitative data analysis organized by dimension of the activity system. This process enabled us to capture the activity and the voices of participants as well as tensions that had emerged in the system. Findings show a range of outcomes, from participants crediting the group as a kickstart to the journey to successfully landing a job as a developer to members stalling in their progress after involvement. Results also show that purposeful tensions of welcoming novice questions and offering unsolicited verbal encouragement built into the activity system create a welcoming, safe environment for women learning to code.

Interfacial Delamination in Plastic Encapsulated Integrated Circuits (Pics)

1996 ◽  
Vol 445 ◽  
Author(s):  
Nickolaos Strifas ◽  
Aris Christou
Keyword(s):  
Integrated Circuits ◽  
Failure Analysis ◽  
Stress Corrosion ◽  
Integrated Circuit ◽  
Point Of View ◽  
Acoustic Microscopy ◽  
Electrical Performance ◽  
Premature Failure ◽  
Interfacial Delamination ◽  
Die Surface

AbstractThe reliability of plastic packaged integrated circuits was assessed from the point of view of interfacial mechanical integrity. It is shown that the effect of structural weaknesses caused by poor bonding, voids, microcracks or delamination may not be evident in the electrical performance characteristics, but may cause premature failure. Acoustic microscopy (C-SAM) was selected for nondestructive failure analysis of the plastic integrated circuit (IC) packages. Integrated circuits in plastic dual in line packages were initially subjected to temperature (25 °C to 85 °C) and humidity cycling (50 to 85 %) where each cycle was of one hour duration and for over 100 cycles and then analyzed. Delamination at the interfaces between the different materials within the package, which is a major cause of moisture ingress and subsequent premature package failure, was measured. The principal areas of delamination were found along the leads extending from the chip to the edge of the molded body and along the die surface itself. Images of the 3-D internal structure were produced that were used to determine the mechanism for a package failure. The evidence of corrosion and stress corrosion cracks in the regions of delamination was identified.

A note on design-based versus model-based variance estimation in stereology

2002 ◽  
Vol 34 (03) ◽  
pp. 484-490 ◽  
Author(s):  
Asger Hobolth ◽  
Eva B. Vedel Jensen
Keyword(s):  
Mathematical Model ◽  
Original Problem ◽  
Variance Estimation ◽  
Point Of View ◽  
Systematic Sampling ◽  
Variance Estimator ◽  
Shape Model ◽  
Model Based ◽  
Versus Model ◽  
Special Case

Recently, systematic sampling on the circle and the sphere has been studied by Gual-Arnau and Cruz-Orive (2000) from a design-based point of view. In this note, it is shown that their mathematical model for the covariogram is, in a model-based statistical setting, a special case of the p-order shape model suggested by Hobolth, Pedersen and Jensen (2000) and Hobolth, Kent and Dryden (2002) for planar objects without landmarks. Benefits of this observation include an alternative variance estimator, applicable in the original problem of systematic sampling. In a wider perspective, the paper contributes to the discussion concerning design-based versus model-based stereology.

Effective Properties of Superconducting and Superfluid Composites

1998 ◽  
Vol 12 (29n31) ◽  
pp. 3063-3073 ◽  
Author(s):  
Leonid Berlyand
Keyword(s):  
Mathematical Model ◽  
Linear Problem ◽  
Effective Properties ◽  
Point Of View ◽  
Periodicity Cell ◽  
Unit Size ◽  
Composite Media ◽  
Homogenization Procedure

We consider a mathematical model which describes an ideal superfluid with a large number of thin insulating rods and an ideal superconductor reinforced by such rods. We suggest a homogenization procedure for calculating effective properties of both composite media. From the numerical point of view the procedure amounts to solving a linear problem in a periodicity cell of unit size.

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