Search results for " Definition"
showing 10 items of 162 documents
What is a tree in the Mediterranean Basin hotspot? A critical analysis
2019
Background: Tree species represent 20% of the vascular plant species worldwide and they play a crucial role in the global functioning of the biosphere. The Mediterranean Basin is one of the 36 world biodiversity hotspots, and it is estimated that forests covered 82% of the landscape before the first human impacts, thousands of years ago. However, the spatial distribution of the Mediterranean biodiversity is still imperfectly known, and a focus on tree species constitutes a key issue for understanding forest functioning and develop conservation strategies. Methods: We provide the first comprehensive checklist of all native tree taxa (species and subspecies) present in the Mediterranean-Europ…
An enhanced approach based on IEEE 1459 for the detection of disturbing loads in distorted and unbalanced three-phase power systems
2009
This paper presents an enhanced approach for the detection of disturbing loads in distorted and/or unbalanced three-phase power systems in both cases of three and four-wires. It is based on the IEEE Std. 1459-2000 effective apparent power resolution and it requires only the separation of the fundamental components of voltage and current from the remaining harmonic content. In the paper, the formulation of the novel approach is given and some simulation results are presented.
A Life Cycle Model of XML Documents
2014
Electronic documents produced in business processes are valuable information resources for organizations. In many cases they have to be accessible long after the life of the business processes or information systems in connection with which they were created. To improve the management and preservation of documents, organizations are deploying Extensible Markup Language (XML) as a standardized format for documents. The goal of this paper is to increase understanding of XML document management and provide a framework to enable the analysis and description of the management of XML documents throughout their life. We followed the design science approach. We introduce a document life cycle model…
Fast Matrix Multiplication
2015
Until a few years ago, the fastest known matrix multiplication algorithm, due to Coppersmith and Winograd (1990), ran in time O(n2.3755). Recently, a surge of activity by Stothers, Vassilevska-Williams, and Le~Gall has led to an improved algorithm running in time O(n2.3729). These algorithms are obtained by analyzing higher and higher tensor powers of a certain identity of Coppersmith and Winograd. We show that this exact approach cannot result in an algorithm with running time O(n2.3725), and identify a wide class of variants of this approach which cannot result in an algorithm with running time $O(n^{2.3078}); in particular, this approach cannot prove the conjecture that for every e > 0, …
Some considerations on the nonabelian tensor square of crystallographic groups
2011
The nonabelian tensor square $G\otimes G$ of a polycyclic group $G$ is a polycyclic group and its structure arouses interest in many contexts. The same assertion is still true for wider classes of solvable groups. This motivated us to work on two levels in the present paper: on a hand, we investigate the growth of the Hirsch length of $G\otimes G$ by looking at that of $G$, on another hand, we study the nonabelian tensor product of pro--$p$--groups of finite coclass, which are a remarkable class of solvable groups without center, and then we do considerations on their Hirsch length. Among other results, restrictions on the Schur multiplier will be discussed.
Patterns of objectively measured sedentary time in 10- to 12-year-old Belgian children: an observational study within the ENERGY-project
2017
Background This study examined the frequency of and differences in sedentary bouts of different durations and the total time spent in sedentary bouts on a weekday, a weekend day, during school hours, during after-school hours and in the evening period in a sample of 10- to 12-year-old Belgian children. Methods Accelerometer data were collected as part of the ENERGY-project in Belgium (n = 577, 10.9 ± 0.7 years, 53% girls) in 2011. Differences in total sedentary time, sedentary bouts of 2–5, 5–10, 10–20, 20–30 and ≥30 min and total time accumulated in those bouts were examined on a weekday, a weekend day, during school hours, during after-school hours and in the evening period, using multile…
Extensional flow of HDPE/LDPE blends
1982
Elongational viscosity data, obtained through the converging flow analysis by Cogswell, are presented for two types of HDPE/LDPE blends at various compositions and different temperatures. The results relative to the homopolymer parents compare favourably with literature data obtained also with different and more sophisticated techniques. Those relative to blends show peculiar features for the two cases: when the newtonian viscosity of the LDPE is higher all the blends show a behaviour typical of the LDPE with a maximum in η el /η0 enhanced at small percentage of HDPE; when the newtonian viscosity of the LDPE is similar to that of the HDPE there is only a gradual change in the properties.
How to Extract Fragments from Agent Oriented Design Processes
2013
Using Method Engineering for creating agent oriented design processes is a challenging task because of the lack of a fragment repository defined and filled starting from a shared and unique definition of fragment. The creation of a repository implies the fragmentation of existing agent design processes. In this paper we propose a set of guidelines for extracting fragments from agent design processes. The work is based on a precise definition of fragment and it aims to establish a method for fragmenting processes and obtaining homogeneous fragments regardless of how the starting design processes are defined and described. © 2013 Springer-Verlag.
The cognitive therapy of evaluation: Therapeutic techniques-[2]
1991
Abstract The main aim of this paper is to introduce the techniques used in cognitive therapy of evaluation. The Cognitive therapy of evaluation is being developed from the theoretical background of general semantics theory and it is a therapy based on language as an instrument of cognitive processes, and on the role it plays, through word-facts identification, in the development and treatment of emotional problems. The main techniques developed (abstraction orders and the extensional devices) and other therapeutic issues are introduced and explained.
Die „Gewichtsphobie” - Ein Diskussionsbeitrag zum Problem der „atypischen” oder „nicht näher bezeichneten”Eß- und Gewichtsstörungen -
2000
A number of authors have stated that the problem of classifying patients whose diagnosis does not meet all the criteria of anorexia and bulimia nervosa has not been satisfactorily solved. The question has been asked if it is justified to regard characteristics like "weight phobia" or body image disturbance as valid diagnostic criteria. In the present study the differences observed in three groups of patients with eating and weight disorders (anorexia: n = 42; bulimia: n = 29; atypical group without "weight phobia": n = 14) were compared using the Giessen-Test. The atypical group was shown to be significantly more "tractable" on scale 2 than the main groups, which achieved a higher score on …