نتایج جستجو برای: during 2009

تعداد نتایج: 1793878  

Journal: :Proceedings of the National Academy of Sciences of the United States of America 2007
M Alex Smith D Monty Wood Daniel H Janzen Winnie Hallwachs Paul D N Hebert

Many species of tachinid flies are viewed as generalist parasitoids because what is apparently a single species of fly has been reared from many species of caterpillars. However, an ongoing inventory of the tachinid flies parasitizing thousands of species of caterpillars in Area de Conservación Guanacaste, northwestern Costa Rica, has encountered >400 species of specialist tachinids with only a...

Journal: :Philosophical transactions. Series A, Mathematical, physical, and engineering sciences 2010
Alison Ord Bruce E Hobbs

Naturally, deformed rocks commonly contain crack arrays (joints) forming patterns with systematic relationships to the large-scale deformation. Kinematically, joints can be mode-1, -2 or -3 or combinations of these, but there is no overarching theory for the development of the patterns. We develop a model motivated by dislocation pattern formation in metals. The problem is formulated in one dim...

Journal: :Physical review. E, Statistical, nonlinear, and soft matter physics 2003
J Buceta M Ibañes J M Sancho Katja Lindenberg

We extend the mechanism for noise-induced phase transitions proposed by Ibañes et al. [Phys. Rev. Lett. 87, 020601 (2001)] to pattern formation phenomena. In contrast with known mechanisms for pure noise-induced pattern formation, this mechanism is not driven by a short-time instability amplified by collective effects. The phenomenon is analyzed by means of a modulated mean field approximation ...

Journal: :Optics letters 2000
P Lodahl M Bache M Saffman

We analyze pattern formation in doubly resonant intracavity second-harmonic generation in the presence of competing nondegenerate parametric downconversion. We show that for positive cavity detuning of the fundamental frequency the threshold for parametric oscillation is lower than that of transverse, pattern forming instabilities. The parametric oscillation strongly modifies the pattern dynami...

Journal: :Physical review. E, Statistical, nonlinear, and soft matter physics 2011
Luo-Luo Jiang Tao Zhou Matjaž Perc Bing-Hong Wang

We investigate the impact of cyclic competition on pattern formation in the rock-paper-scissors game. By separately considering random and prepared initial conditions, we observe a critical influence of the competition rate p on the stability of spiral waves and on the emergence of biodiversity. In particular, while increasing values of p promote biodiversity, they may act detrimentally on spat...

Journal: :Physical review. E, Statistical, nonlinear, and soft matter physics 2006
Kevin Wood Javier Buceta Katja Lindenberg

We present a comprehensive study of pattern formation in single-field relaxational systems with field-dependent coefficients. A modulated mean-field theory leads to a form amenable to analysis via the geometric architecture developed in our earlier work for systems that exhibit phase transitions between global steady states [Phys. Rev. E 69, 011102 (2004)]. We demonstrate that the phase diagram...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه علامه طباطبایی - دانشکده اقتصاد 1389

this thesis is a study on insurance fraud in iran automobile insurance industry and explores the usage of expert linkage between un-supervised clustering and analytical hierarchy process(ahp), and renders the findings from applying these algorithms for automobile insurance claim fraud detection. the expert linkage determination objective function plan provides us with a way to determine whi...

2016
Amira Chaabane Lassad Neifar Delphine Gey Jean-Lou Justine

Pseudorhabdosynochus Yamaguti, 1958 is a species-rich diplectanid genus, mainly restricted to the gills of groupers (Epinephelidae) and especially abundant in warm seas. Species from the Mediterranean are not fully documented. Two new and two previously known species from the gills of Mycteroperca spp. (M. costae, M. rubra, and M. marginata) in the Mediterranean and Eastern Atlantic Ocean are d...

Journal: :Folia biologica 2003
Jörg Bohlen Vendula Slechtová Radek Sanda Lucás Kalous Jörg Freyhof Jasna Vukic Danilo Mrdak

In this paper, we report on the distribution, habitat, population structure and conservation needs of Cobitis ohridana and Barbatula zetensis in the basin of the River Moraca in Montenegro. Our data show both species to be mainly distributed in the lower stretch of the main river and some tributaries in lowland habitats. Cobitis ohridana preferred more shallow water with a higher abundance of f...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید