scholarly journals Generative capacity of kolam patterns using Tile pasting rules

2021 ◽  
Vol 1770 (1) ◽  
pp. 012087
Author(s):  
M.I.Mary Metilda ◽  
Lalitha D
Keyword(s):  
Generative Capacity

TOWARD UNDERSTANDING THE GENERATIVE CAPACITY OF ERASING RULES IN MATRIX GRAMMARS

2011 ◽  
Vol 22 (02) ◽  
pp. 411-426 ◽  
Author(s):  
GEORG ZETZSCHE
Keyword(s):  
Petri Net ◽  
Open Problem ◽  
Generative Capacity ◽  
Arbitrary Matrix ◽  
Matrix Grammar ◽  
Sentential Form

This article presents approaches to the open problem of whether erasing rules can be eliminated in matrix grammars. The class of languages generated by non-erasing matrix grammars is characterized by the newly introduced linear Petri net grammars. Petri net grammars are known to be equivalent to arbitrary matrix grammars (without appearance checking). In linear Petri net grammars, the marking has to be linear in size with respect to the length of the sentential form. The characterization by linear Petri net grammars is then used to show that applying linear erasing to a Petri net language yields a language generated by a non-erasing matrix grammar. It is also shown that in Petri net grammars (with final markings and arbitrary labeling), erasing rules can be eliminated, which yields two reformulations of the problem of whether erasing rules in matrix grammars can be eliminated.

scholarly journals Cross-national comparisons of human resources for health – what can we learn?

2005 ◽  
Vol 1 (1) ◽  
pp. 59-78 ◽  
Author(s):  
CARL-ARDY DUBOIS ◽  
MARTIN MCKEE
Keyword(s):  
Human Resources ◽  
Comparative Studies ◽  
Human Resources For Health ◽  
Health Sector ◽  
International Health ◽  
Comparative Approach ◽  
Generative Capacity ◽  
International Comparative ◽  
Context Specific ◽  
Cross National

After a long period of neglect, the issue of human resources for health (HRH) has recently emerged as a core component on the international health agenda, with policy makers increasingly eager to learn from experience elsewhere. This article investigates systematically the opportunities and challenges associated with the use of cross-national comparisons of HRH policies and practices. It reviews the evidence in favour of using international comparative studies on HRH, discusses emerging opportunities for developing a cross-national research agenda to guide HRH policies in Europe, and highlights obstacles which may hinder the implementation of comparative studies on HRH. While demonstrating many opportunities offered by the comparative approach to improve understanding of human resources processes in the health sector, this article also emphasizes the dangers of simplistic pleas for the transfer of human resource policies without taking into account the context-specific factors and the generative capacity of the social actors in the design and implementation of policy changes.

Everyday agency and transformation: Place, body and story in the divided city

2018 ◽  
Vol 54 (2) ◽  
pp. 131-148 ◽  
Author(s):  
Johanna Mannergren Selimovic
Keyword(s):  
Coping Mechanisms ◽  
Status Quo ◽  
Embodied Experience ◽  
Human Beings ◽  
Generative Capacity ◽  
Peace And Conflict ◽  
Analytical Work ◽  
The Everyday ◽  
The World ◽  
The City

How do we identify and understand transformative agency in the quotidian that is not contained in formal, or even informal structures? This article investigates the ordinary agency of Palestinian inhabitants in the violent context of the divided city of Jerusalem. Through a close reading of three ethnographic moments I identify creative micropractices of negotiating the separation barrier that slices through the city. To conduct this analytical work I propose a conceptual grid of place, body and story through which the everyday can be grasped, accessed and understood. ‘Place’ encompasses the understanding that the everyday is always located and grounded in materiality; ‘body’ takes into account the embodied experience of subjects moving through this place; and ‘story’ refers to the narrative work conducted by human beings in order to make sense of our place in the world. I argue that people can engage in actions that function both as coping mechanisms (and may even support the upholding of status quo), and as moments of formulating and enacting agential projects with a more or less intentional transformative purpose. This insight is key to understanding the generative capacity of everyday agency and its importance for the macropolitics of peace and conflict.

scholarly journals Predicting drug polypharmacology from cell morphology readouts using variational autoencoder latent space arithmetic

2021 ◽  
Author(s):  
Yuen Ler Chow ◽  
Shantanu Singh ◽  
Anne E Carpenter ◽  
Gregory P. Way
Keyword(s):  
Gene Expression ◽  
Cell Morphology ◽  
Learning Algorithm ◽  
Simulated Data ◽  
Biomedical Data ◽  
Data Types ◽  
Generative Capacity ◽  
Latent Space ◽  
Variational Autoencoder ◽  
Target Effects

A variational autoencoder (VAE) is a machine learning algorithm, useful for generating a compressed and interpretable latent space. These representations have been generated from various biomedical data types and can be used to produce realistic-looking simulated data. However, standard vanilla VAEs suffer from entangled and uninformative latent spaces, which can be mitigated using other types of VAEs such as β-VAE and MMD-VAE. In this project, we evaluated the ability of VAEs to learn cell morphology characteristics derived from cell images. We trained and evaluated these three VAE variants-Vanilla VAE, β-VAE, and MMD-VAE-on cell morphology readouts and explored the generative capacity of each model to predict compound polypharmacology (the interactions of a drug with more than one target) using an approach called latent space arithmetic (LSA). To test the generalizability of the strategy, we also trained these VAEs using gene expression data of the same compound perturbations and found that gene expression provides complementary information. We found that the β-VAE and MMD-VAE disentangle morphology signals and reveal a more interpretable latent space. We reliably simulated morphology and gene expression readouts from certain compounds thereby predicting cell states perturbed with compounds of known polypharmacology. Inferring cell state for specific drug mechanisms could aid researchers in developing and identifying targeted therapeutics and categorizing off-target effects in the future.

Completion Grammars and Completion Automata Revisited

1977 ◽  
Vol 37 ◽  
pp. 19-40
Author(s):  
Luc Steels
Keyword(s):  
Language Processing ◽  
Word Order ◽  
Generative Capacity ◽  
New Class ◽  
Automatic Translation ◽  
Linguistic Model ◽  
Transition Functions ◽  
Finite State ◽  
Formal Properties

An extension of completion grammars is being introduced such that the model now deals with prefix, infix, postfix and post-infix word order patterns. It is shown that this extension does not affect the weak generative capacity of the system, which was known to be of type 2. Also the existing notion of a completion automaton is reworked, mainly to have the distinction in word order be reflected by the operations of the automaton rather than by the transition functions of the underlying finite state machine. In some recent publications (e.g. Steels (1975), Steels and Vermeir (1976), Steels (1976a&b» we have been dealing with a linguistic model known as compZetion grammars. These grammars were designed to cope with a functional viewpoint on language, this means they deal with case structures for language,expressions, instead of phrase structures as do the well-known Chomsky-type grammars. The model of completion grammars was developed in a context of research on language processing and automatic translation. In particular it reflects the current tendency to build semantics directed systems, rather than syntax directed ones. (See for a more detailed discussion on the distinction between the two Wilks (1975) and Winograd (1973). For the use of completion grammars in the design of semantics directed systems, we refer to Steels (1975;1976a&b). What will concern us in this paper is an extension of the model, and a study of the formal properties of these extended systems. Also we will introduce a new class of automata. The paper is organized as follows. First we extend the notion of a completion grammar, we give some intuitive explanations for the extension (1.1.), specify the basic definitions (1.2.) and study its weak generative capacity (1.3.). A second section deals with the automata. Again we start with intuitive explanations (2.1.), give the basic definitions and various examples (2.2.) and finally prove the relation between the grammars and the automata (2.3.).

A COMPARISON OF THE DESCRIPTIONAL COMPLEXITY OF CLASSES OF LIMITED LINDENMAYER SYSTEMS: PART I

2012 ◽  
Vol 23 (01) ◽  
pp. 99-114
Author(s):  
RONNY HARBICH ◽  
BIANCA TRUTHE
Keyword(s):  
The Other ◽  
Lindenmayer Systems ◽  
Generative Capacity ◽  
Descriptional Complexity

We investigate the descriptional complexity of limited Lindenmayer systems and their deterministic and tabled variants with respect to the number of rules and the number of symbols. In this part, we confine ourselves to propagating limited Lindenmayer systems. We determine the decrease of complexity when the generative capacity is increased. For incomparable families, we give languages that can be described more efficiently in either of these families than in the other.

COMPUTATION BY ANNOTATION: MODELLING EPIGENETIC REGULATION

2008 ◽  
Vol 19 (05) ◽  
pp. 1087-1098
Author(s):  
FRANZISKA BIEGLER ◽  
MARK DALEY ◽  
M. ELIZABETH O. LOCKE
Keyword(s):  
Histone Modification ◽  
Epigenetic Regulation ◽  
Formal Model ◽  
Gene Annotation ◽  
Formal System ◽  
Regular Languages ◽  
Generative Capacity ◽  
Epigenetic Process

We present a formal model inspired by the epigenetic process of gene annotation via histone modification. In particular, we study the generative capacity of a system in which annotations on a set of strings control which substrings are ultimately produced by the system and in which only the annotations, and not the strings themselves, may be rewritten. On a biological level this represents a first attempt to better understand the computational limits of this form of epigenetic regulation. We introduce two different derivation modes for our formal system and show that these systems are actually quite weak. The weaker of the derivation modes is directly capable only of generating a subset of the regular languages while the more powerful derivation mode is also only capable of generating all regular languages modulo a begin- and an end-marker.

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