1,777 research outputs found
Integrated geometry and grid generation system for complex configurations
A grid generation system was developed that enables grid generation for complex configurations. The system called ICEM/CFD is described and its role in computational fluid dynamics (CFD) applications is presented. The capabilities of the system include full computer aided design (CAD), grid generation on the actual CAD geometry definition using robust surface projection algorithms, interfacing easily with known CAD packages through common file formats for geometry transfer, grid quality evaluation of the volume grid, coupling boundary condition set-up for block faces with grid topology generation, multi-block grid generation with or without point continuity and block to block interface requirement, and generating grid files directly compatible with known flow solvers. The interactive and integrated approach to the problem of computational grid generation not only substantially reduces manpower time but also increases the flexibility of later grid modifications and enhancements which is required in an environment where CFD is integrated into a product design cycle
Need to categorize: A comparative look at the categories of the Universal Decimal Classification system (UDC) and Wikipedia
This study analyzes the differences between the category structure of the
Universal Decimal Classification (UDC) system (which is one of the widely used
library classification systems in Europe) and Wikipedia. In particular, we
compare the emerging structure of category-links to the structure of classes in
the UDC. With this comparison we would like to scrutinize the question of how
do knowledge maps of the same domain differ when they are created socially
(i.e. Wikipedia) as opposed to when they are created formally (UDC) using
classificatio theory. As a case study, we focus on the category of "Arts".Comment: Paper for High Throughput Humanities - a satellite meeting at the
European Conference on Complex Systems 2010; Sept. 15, 2010 Lisbon University
Institute ISCTE, Lisbon, Portuga
The Development of the Journal Environment of Leonardo
We present animations based on the aggregated journal-journal citations of
Leonardo during the period 1974-2008. Leonardo is mainly cited by journals
outside the arts domain for cultural reasons, for example, in neuropsychology
and physics. Articles in Leonardo itself cite a large number of journals, but
with a focus on the arts. Animations at this level of aggregation enable us to
show the history of the journal from a network perspective
The effect of disjoining pressure on the shape of condensing films in a fin-groove corner
Thin film condensation is commonly present in numerous natural and artificial
processes. Phase-change driven passive heat spreaders such as heat pipes, which
are widely used in electronics cooling, employ a continuous condensation
process at the condenser region. When the wick structure of a heat pipe is
composed of grooves, the top surfaces of the walls (fins) located between
consecutive grooves function as the major source of condensation and the
condensate flows along the fin top into the grooves. Modeling of this
condensation problem is vital for the proper estimation of condensation heat
transfer, which constitutes the basis for the overall performance of an heat
pipe together with the evaporation process. In the current study, a solution
methodology is developed to model the condensation and associated liquid flow
in a fin-groove system. Conservation of mass and momentum equations, augmented
Young-Laplace equation and Kucherov-Rikenglaz equation are solved
simultaneously to calculate the film thickness profile. The model proposed
enables the investigation of the effect of disjoining pressure on the film
profile by keeping the fin-groove corner, where the film becomes thinnest,
inside the solution domain. The results show that dispersion forces become
effective for near isothermal systems with sharp fin-groove corners and the
film profile experiences an abrupt change, a slope break, in the close
proximity of the corner. The current study is the first computational
confirmation of this behavior in the literature
The structure of the Arts & Humanities Citation Index: A mapping on the basis of aggregated citations among 1,157 journals
Using the Arts & Humanities Citation Index (A&HCI) 2008, we apply mapping
techniques previously developed for mapping journal structures in the Science
and Social Science Citation Indices. Citation relations among the 110,718
records were aggregated at the level of 1,157 journals specific to the A&HCI,
and the journal structures are questioned on whether a cognitive structure can
be reconstructed and visualized. Both cosine-normalization (bottom up) and
factor analysis (top down) suggest a division into approximately twelve
subsets. The relations among these subsets are explored using various
visualization techniques. However, we were not able to retrieve this structure
using the ISI Subject Categories, including the 25 categories which are
specific to the A&HCI. We discuss options for validation such as against the
categories of the Humanities Indicators of the American Academy of Arts and
Sciences, the panel structure of the European Reference Index for the
Humanities (ERIH), and compare our results with the curriculum organization of
the Humanities Section of the College of Letters and Sciences of UCLA as an
example of institutional organization
Evolution of Wikipedia's Category Structure
Wikipedia, as a social phenomenon of collaborative knowledge creating, has
been studied extensively from various points of views. The category system of
Wikipedia, introduced in 2004, has attracted relatively little attention. In
this study, we focus on the documentation of knowledge, and the transformation
of this documentation with time. We take Wikipedia as a proxy for knowledge in
general and its category system as an aspect of the structure of this
knowledge. We investigate the evolution of the category structure of the
English Wikipedia from its birth in 2004 to 2008. We treat the category system
as if it is a hierarchical Knowledge Organization System, capturing the changes
in the distributions of the top categories. We investigate how the clustering
of articles, defined by the category system, matches the direct link network
between the articles and show how it changes over time. We find the Wikipedia
category network mostly stable, but with occasional reorganization. We show
that the clustering matches the link structure quite well, except short periods
preceding the reorganizations.Comment: Preprint of an article submitted for consideration in Advances in
Complex Systems (2012) http://www.worldscinet.com/acs/, 19 pages, 7 figure
Adiponectin and Cardiac Hypertrophy in Acromegaly
Background. Adiponectin is an adipocytes-derived hormone which has been shown to possess insulin-sensitizing, antiatherogenic, and anti-inflammatory properties. In acromegaly, the data on adiponectin is contradictory. The relationship between adiponectin levels and cardiac parameters has not been studied.Objectives. The aim of this study was to find out how adiponectin levels were affected in acromegalic patients and the relationship between adiponectin levels and cardiac parameters.Material and Methods. We included 30 subjects (15 male, 15 female), diagnosed with acromegaly and 30 healthy (10 male, 20 female) subjects. Serum glucose, insulin, GH, IGF-1 and adiponectin levels were obtained and the insulin resistance of the subjects was calculated. Echocardiographic studies of the subjects were performed.Results. We determined that adiponectin levels were significantly higher in the acromegalic group than the control group. In the acromegalic group, there was no statistically significant relation between serum adiponectin and growth hormone (GH), or insulin-like growth factor-1 (IGF-1) levels (p = 0.3, p = 0.1). We demonstrated that cardiac function and structure are affected by acromegaly. IVST, PWT, LVMI, E/A ratio, DT, ET, IVRT, VPR, and LVESV values were increased and the results were statistically significant. In the acromegalic group, adiponectin levels were positively related with left ventricle mass index (LVMI) but this correlation was found to be statistically weak (p = 0.03). In our study, there was a positive correlation between VAI and LVM. We also could not find any correlation between VAI and adiponectin levels.Conclusions. Although insulin resistance and high insulin levels occur in active acromegaly patients, adiponectin levels were higher in our study as a consequence of GH lowering therapies. Our study showed that adiponectin levels may be an indicator of the cardiac involvement acromegaly. However, the usage of serum adiponectin levels in acromegalic patients as an indicator of cardiac involvement should be supported with other, wide, multi-centered studies
THE IMPORTANCE OF COLLABORATION AMONG BALKAN STUDIES IN TURKEY AND EUROPEAN UNIVERSITIES
The Balkans connect the two old continents and different civilizations. So it is aplace of mixed melting pot of different peoples and cultures throughout history.After the World War II disintegration of the former Soviet bloc gained momentum with the phenomenon of globalization, along with the need to build relations with other states in the Balkan countries. They started to hear. This situation is commonground brings together around the region and other European countries. European Universities and Universities of Turkey were founded research centers for theunique structure of Balkans. These centers have investigated, historical relations with each other countries, trying to establish new relationships in different areas. If they cooperation with together, they will improve its effectiveness and efficiency
Multiphase Modeling of Water Injection on Flame Deflector
This paper describes the use of an Eulerian Dispersed Phase (EDP) model to simulate the water injected from the flame deflector and its interaction with supersonic rocket exhaust from a proposed Space Launch System (SLS) vehicle. The Eulerian formulation, as part of the multi-phase framework, is described. The simulations show that water cooling is only effective over the region under the liquid engines. Likewise, the water injection provides only minor effects over the surface area under the solid engines
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