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1

Algoritmo genetico para o problema de rotas de cobertura multiveiculo  

E-print Network

Algoritmo gen´etico para o problema de rotas de cobertura multive´iculo Washington Alves de¸c~oes sub´otimas s~ao obtidas aplicando-se duas propostas de algoritmo gen´etico (AG), os quais geram rotas de tamanho menor poss´ivel. Palavras-chave: Programa¸c~ao inteira e combinat´oria, algoritmo gen´etico

Gomes, Francisco A. M.

2

Un estudio sobre el uso de algoritmos geneticos multimodales  

E-print Network

Un estudio sobre el uso de algoritmos geneticos multimodales para seleccion de caractersticas J propuestas de algoritmos geneticos multimodales pa- ra seleccion de caractersticas como etapa de reduc- cion. La ex- perimentacion realizada muestra la adecuacion de es- te tipo de algoritmos geneticos para el

Granada, Universidad de

3

Optimizacion de Algoritmos Geneticos en el Procesamiento de Arboles de Steiner  

E-print Network

Optimizaci´on de Algoritmos Gen´eticos en el Procesamiento de ´Arboles de Steiner M´ario Jesus, S´isticas de los Algoritmos Gen´eticos parecen ser muy apropiadas para poder abordar problemas de resoluci mejorar a´un m´as esas propiedades. Palabras Clave: ´arbol de Steiner, puntos de Steiner, algoritmos gen´eticos

Jesus, Sérgio M.

4

Investigation of a Biological Repair Scheme Vincent Danos1  

E-print Network

Investigation of a Biological Repair Scheme Vincent Danos1 , J´er^ome F´eret2 , Walter Fontana3 , Russell Harmer4 , and Jean Krivine3 1 University of Edinburgh 2 INRIA, CNRS, ´Ecole Normale Sup´erieure 3

Fontana, Walter

5

Rule-based modelling, symmetries, refinements Vincent Danos1,3,4  

E-print Network

Rule-based modelling, symmetries, refinements Vincent Danos1,3,4 , J´er^ome Feret2 , Walter Fontana3 , Russell Harmer3,4 , and Jean Krivine5 1 University of Edinburgh 2 ´Ecole Normale Sup´erieure 3

Fontana, Walter

6

Rule-Based Modelling of Cellular Signalling Vincent Danos1,3,4  

E-print Network

Rule-Based Modelling of Cellular Signalling Vincent Danos1,3,4 , J´er^ome Feret2 , Walter Fontana3 , Russell Harmer3,4 , and Jean Krivine5 1 Plectix Biosystems 2 ´Ecole Normale Sup´erieure 3 Harvard Medical

Fontana, Walter

7

Svelato il codice genetico del lievito enologico  

Microsoft Academic Search

Primi al mondo, i ricercatori del 'The Australian Wine Research Institute' hanno completato il sequenziamento del genoma di un lievito enologico, descrivendo le 'ricette vitali' che danno forma all'amico dell'enologo. Questa ricerca apre la strada allo sviluppo di nuovi ceppi di lievito, in grado di offrire soluzioni innovative per il problema degli arresti di fermentazione, e di aumentare la gamma

Anthony R. Borneman; Angus H. Forgan; Paul J. Chambers; Isak S. Pretorius

8

Algoritmo genetico para la Descomposicion de Minkowski de poligonos convexos  

E-print Network

Algoritmo gen´etico para la Descomposici´on de Minkowski de pol´igonos convexos Edilma O´i presentamos un algoritmo gen´etico para el problema. 1 Introducci´on En diversas disciplinas actuales como rob´i presentamos una propuesta usando Algoritmos Gen´eticos, para resolver el problema de la de- scomposici´on de

Llanos, Diego R.

9

CONTROL EN LINEA CON ALGORITMOS GENETICOS Y RECOCIDO SIMULADO  

Microsoft Academic Search

An intelligent control method is presented, it used a PID law, first a set of gains is calculated by a floating point genetic algorithm in off line mode , then the system work on line in adaptive mode with gains change trough a simulated annealing algorithm, it is more fast than a genetic algorithm and them is selected for real

JOSÉ GABRIEL; JAIBER EVELIO CARDONA; RAMIRO ARANGO

2007-01-01

10

Extraccion de Conocimiento Mediante un Algoritmo Genetico Multiobjetivo Estilo  

E-print Network

Extracci´on de Conocimiento Mediante un Algoritmo Gen´etico Multiobjetivo Estilo Pittsburgh y con t´ecni- cas de optimizaci´on tales como las redes neurona- les [4], [5] y los algoritmos gen´eticos alto grado de interpreta- bilidad, proponemos el uso de algoritmos gen´eticos ya que creemos que

Casillas Barranquero, Jorge

11

Cooperative Assembly Systems Vincent Danos1  

E-print Network

this regulation relates to theirs processing information. As a first step, this paper investigates a class (as implicit functions of the cooperativity parameters). By combining both steps, we can derive large-scale objects. One would like to understand their assembly and how this assembly is regulated

Lygeros, John

12

Un Algoritmo Genetico para Aprendizaje de un Sistema Basado en Reglas Difusas tipo  

E-print Network

Un Algoritmo Gen´etico para Aprendizaje de un Sistema Basado en Reglas Difusas tipo Takagi Sugeno F´atico, sistemas basados en reglas difusas TS, algoritmos gen´eticos, I. INTRODUCCI ´ON El modelado difuso ling´on por m´inimos cuadrados. Para la definici´on de la BD se emplear´a un Algoritmo Gen´etico que incluye

Granada, Universidad de

13

AMLIORATION DES PLANTES Avance en el mejoramiento genetico del trigo en  

E-print Network

periodo invierno-primavera de 1982-83 y de 1983-84, se evaluaron 81 variedades de trigo (Triticum aestivum breeding in Mexico. During the winter-spring of 1982-83 and 1983-84, 81 wheat varieties (Triticum aestivum: Triticum aestivum, Mexican wheat program, wheat yield in Mexico, yield components, grain filling rate

Boyer, Edmond

14

Pauli measurements are universal Vincent Danos (CNRS, Univ Paris 7)  

E-print Network

as an important theoretical quantum computing model, it is only recently that some of its measurement patterns a potentially useful simplification of the underlying hardware needed to realise the feedforward mechanism. We is irrelevant to the result of a computation. The instruction M i stands for a one qubit measurement applied

Danos, Vincent - Laboratoire Preuves, Programmes et Systèmes, Université Paris 7

15

CIBIO, Centro de Investigaca~o em Biodiversidade e Recursos Geneticos, Vaira~o, Portugal; 2 Division of Evolutionary Biology,  

E-print Network

Division of Evolutionary Biology, Zoological Institute, Technical University of Braunschweig, Germany; 3¨r Evolutions- und Biodiversita¨tsforschung, Humboldt-Universita¨t, Berlin, Germany; 5 Zoologische Staatssammlung Mu¨nchen, Sektion Herpetologie, Mu¨nchen, Germany; 6 Museo Regionale di Scienze Naturali, Sezione

Brown, Jason

16

1. Perch tutti gli organismi viventi (a parte le solite, rare, eccezioni usano lo stesso insieme di  

E-print Network

altri aa #12;#12;#12;#12;Vedi codice genetico #12;Vedi codice genetico #12;Vedi codice genetico #12 ruota il vettore di stato di un angolo fissato nel piano dei vettori |i> - |s> #12;Algoritmo di Grover angolo fissato l'algoritmo termina dopo un # di passi Q, quando (­RsRi)Q |s> = |i> L'equazione è risolta

Morante, Silvia

17

Análisis de cerámicas romanas Terra Sigillata mediante espectroscopía de plasmas inducidos por láser (LIPS)  

Microsoft Academic Search

Laser induced plasma spectroscopy (LIPS) has been applied for the elemental analysis of roman pottery Terra Sigillata from different ceramic production centers. For each sample, representative LIP spectra of slip and body were obtained in addition of compositional depth profiles. In all the cases investigated, calcium and iron are the elements which best define the transition between slip and body

A. J. LóPez; G. NICoLáS; A. RAMIL; A. Yáñez

18

TOTAL SCORE AS A GENETIC INDEX OF MEAT QUALITY TRAITS IN CHIANINA BEEF CATTLE IL TOTAL SCORE QUALE INDICE GENETICO DELLA QUALITÀ DELLA CARNE DELLA RAZZA CHIANINA  

Microsoft Academic Search

SUMMARY The aim of this research was to study a Total Score Index, capable to resume the meat quality traits, and useful for improvement programs. The quality of meat from the Longissimus dorsi muscle, of 82 Chianina bulls, was analysed. The animals, reared in two Tuscan farms with different feeding-programs, were slaughtered at about 19 months of age. Colour traits,

Valeria Casavola

19

Graphs for Core Molecular Biology Vincent Danos 1 and Cosimo Laneve 2  

E-print Network

of private names, spanning all participants in the reaction. Along this recruitment phase, it is also checked collaborators, have convincingly argued that low­level name­based communication languages [10, 7] may prove level. As fas­ cinating as this new and potentially huge field of application may be, it is still

Danos, Vincent - Laboratoire Preuves, Programmes et Systèmes, Université Paris 7

20

Pressa il sodio e diventer isolante Lo conferma un articolo su Nature firmato anche da un studioso ticinese  

E-print Network

strutture cristalline. E lo fa con un procedimento genetico. Sul- la base di pochissimi dati inizia- li- litecnico di Zurigo, era uno dei maggioriutentidelCSCSdiMan- no. «Integrando il software nel- l'algoritmo genetico di Oganov, abbiamogeneratounavalangadi strutture», spiega Valle, «alla ri- cerca di quella

Oganov, Artem R.

21

Universit`a degli Studi di Napoli "Federico II"  

E-print Network

. . . . . . . . . . . . . . . . . . 71 3.3.2 Progettare un algoritmo genetico . . . . . . . . . . . . 74 4 Il lavoro sperimentale 79 4 . . . . . . . . . . . . . . . . . 108 4.6 Limiti dell'algoritmo genetico realizzato . . . . . . . . . . . . . 110 4.7 Considerazioni ricerca . . . 49 2.3.2 Strategie di ricerca nel reticolo . . . . . . . . . . . . . . 51 2.3.3 L'algoritmo

Mazzei, Alessandro

22

Universita degli Studi di Napoli ``Federico II''  

E-print Network

. . . . . . . . . . . . . . . . . . 71 3.3.2 Progettare un algoritmo genetico . . . . . . . . . . . . 74 4 Il lavoro sperimentale 79 4 . . . . . . . . . . . . . . . . . 108 4.6 Limiti dell'algoritmo genetico realizzato . . . . . . . . . . . . . 110 4.7 Considerazioni ricerca . . . 49 2.3.2 Strategie di ricerca nel reticolo . . . . . . . . . . . . . . 51 2.3.3 L'algoritmo

Mazzei, Alessandro

23

The Condor 110(1):112 c The Cooper Ornithological Society 2008  

E-print Network

of a population of Wild Turkeys (Meleagris gallopavo), a promiscuous species in which males and potentially, polygyny. Selecci´on Sexual y el Sistema de Apareamiento Gen´etico de Meleagris gallopavo Resumen. Las apareamiento gen´etico de una poblaci´on de Meleagris gallopavo. Esta es una especie promiscua en la cual los

Patricelli, Gail

24

GUADALAJARA JALISCO 2005 XLVIII CONGRESO NACIONAL SMF / XVIII REUNION ANUAL AMO Estudio de efectos foto-inducidos en modelos de  

E-print Network

experimentos descrita en el trabajo. Esperamos obtener resultados, cuyo análisis, nos ayude a obtener sustituir herramientas tradicionales de ese campo por láseres. Estos son fácil de controlar, seguros

Aguilar, Guillermo

25

Mixing Mechanism of a Discrete Co-Flow Jet Airfoil Bertrand P. E. Dano, Alexis Lefebvre and Gecheng Zha  

E-print Network

S Wing span area m Jet mass flow rate u,v,w Velocity components in x-, y-, and z-direction V Velocity) is to increase lift and stall margin, and reduce drag with low energy expenditure and minimal solid structure on an actual airplane can be obtained by using pressurized air from the aircraft engines to supply the jet

Zha, Gecheng

26

CROP PROTECTION Avaliação de Danos de Percevejos e de Desfolhadores em Genótipos de Soja de Ciclos Precoce, Semiprecoce e Médio  

Microsoft Academic Search

The damage of stinkbugs and defoliators in soybean genotypes was evaluated, under field conditions, at Tarumã and Ribeirão Preto, State of São Paulo, Brazil. Three experiments, one for each of three maturity group, were carried out, in the 1997\\/98 and 1998\\/99 seasons. In Tarumã, infestations of Diabrotica speciosa (Germar) and Cerotoma sp. occurred in both seasons and Anticarsia gemmatalis Hubn.

ANDRÉ L. LOURENÇÃO; NELSON R. BRAGA; MANOEL A. C. MIRANDA; GIULIANA E. VALLE

27

Society for Conservation Biology Blackwell Publishing Society for Conservation Biology  

E-print Network

estocacidad demogrdfica puede ser la mayor amenaza para poblaciones pequenias y aisladas de lobos, aunque la estocacidad ambiental y los efec- tos geneticos pueden complicar esta amenaza. Nuestro trabajo resalta la

28

Contributed Paper Evolutionary Distinctiveness, Threat Status,  

E-print Network

Singularidad Evolutiva, Estatus de Amenaza y Rareza Ecol´ogica en Primates Resumen: El programa de conservaci compuesta de la amenaza y el aislamiento gen´etico para clasificar especies para atenci´on de la conservaci

Mooers, Arne

29

POLITECNICO DI TORINO Facolt di Ingegneria  

E-print Network

.................................................................................................................. 3 2 Un Algoritmo Genetico per il Job Shop........................................................................................... 12 3.1 Schema dell'Algoritmo di Ricerca Genetica Locale........................................ 12 3.3 Algoritmo di Ricerca Loacle........................................................................... 14 4

Yao, Xin

30

Fisica Biologica 2 programma svolto 2009-2010  

E-print Network

algoritmo per individuarla. 9. Le scelte evolutive e la loro necessità. Il folding spontaneo e le catene di -amino acidi. 10. Degenerazione del codice genetico: evoluzione da un codice a doppiette ad uno

Morante, Silvia

31

El Octreotide incrementa el efecto hipotensor portal inducido por el bloqueo beta-adrenérgico crónico en pacientes cirróticos. Estudio randomizado y controlado  

Microsoft Academic Search

Aim: To evaluate HVPG effects of octreotide administration in cirrhotic patients receiving long-term propranolol. Patients & Methods: A randomized, controlled trial. First study: 28 patients were studied at baseline and 30' and 60' after octreotide (200 g) (n:14) or placebo (n:14) and then treated with propranolol for approximately 30 days (1065 mg\\/day). Second study: after baseline evaluation patients received octreotide

Julio D. Vorobioff; Sebastián Ferretti; Pedro Zangroniz; Marcelo Gamen; Eduardo Picabea; Carina Maglione; Virginia Reggiardo; Fernando Bessone; Ana Diez; Mario Tanno; Cristina Cuesta; Hugo Tanno

32

Steep clines within a highly permeable genome across a hybrid zone between two subspecies of the  

E-print Network

of the European rabbit MIGUEL CARNEIRO,* STUART J. E. BAIRD,* SANDRA AFONSO,* ESTHER RAMIREZ,§ PEDRO TARROSO Investigacß~ao em Biodiversidade e Recursos Geneticos, Campus Agrario de Vair~ao, Universidade do Porto, 4485 between hybridizing taxa. Correspondence: Miguel Carneiro, Fax: (+351) 25 266 1780; E-mail: miguel

Nachman, Michael

33

Transcriptional Activity, Chromosomal Distribution and Expression Effects of Transposable Elements in Coffea  

E-print Network

, Sa~o Jose´ do Rio Preto, Brazil, 2 School of Biology, Georgia Institute of Technology, Atlanta, Londrina, Brazil, 4 Empresa Brasileira de Pesquisa Agropecua´ria Recursos Gene´ticos e Biotecnologia (LGM), Brasi´lia, Brazil, 5 Centre de Coope´ration Internationale en Recherche Agronomique pour le De

Jordan, King

34

Detección y estudio mediante Fluorescencia Inducida por Láser de radicales libres formados por Disociación Multifotónica Infrarroja  

Microsoft Academic Search

Una de las principales aplicaciones actuales de los procesos de disociación multifotónica inducidos por radiación láser infrarroja (DMI) es la producción de radiales libres, con el fin de estudiar sus propiedades cinéticas y espectroscópicas. La disociación de moléculas poliatómicas en el IR con láseres de CO2 tiene lugar desde la superficie de energía molecular mas baja y conduce generalmente a

M. Santos; L. Díaz; J. A. Torresano; L. Rubio; B. Samoudi

2003-01-01

35

Aglomeración económica y congestión vial: los perjuicios por racionamiento del tráfico vehicular  

Microsoft Academic Search

La creciente urbanización latinoamericana de las últimas décadas ha inducido mayor demanda de vehículos y congestión de tráfico. Pretendiendo aliviar los costos de la congestión se han adoptado medidas polémicas que restringen la circulación del 20% o el 40% de los vehículos cada día de la semana laboral -en México 1988 y Bogotá 2008, “Pico y Placa”-. Para juzgar la

Carlos Alberto Medina; Carlos Eduardo Vélez

2011-01-01

36

Mantillas in Muscovy  

E-print Network

those who comprised my dissertation committee: Willis Barnstone, John C. Dowling, William B. Edgerton, Miguel Engui- danos, and Walter Poesse, of Indiana University; as well as Mikhail P. Alekseev of Pushkinskii Dom (Leningrad) and Zakharii L Plavskin...

Weiner, Jack

1970-01-01

37

Vinhoto e cama de frango como coadjuvantes na compostagem de bagaço de cana de açúcar  

Microsoft Academic Search

Resumo: Atualmente, a agricultura está passando por um proc esso de modernização, trazendo com isso inúmeros fatores negativos que influenciam na degradação do meio ambiente. Dejetos estão sendo jogados em lugares impróprios trazendo danos ao ar, solo e águas. Percebendo a gravidade deste problema, este trabalho foi realiza do visando contribuir para o melhoramento das condições ambientais e propor renda

Fernando Lira; Renato Cassol de Oliveira

2008-01-01

38

PLANT RESISTANCE Evaluation of Onion Cultivars for Resistance to Onion Thrips  

E-print Network

´todos, estudios en campo sobre resistencia de la cebolla a T. tabaci se llevaron a cabo en 2007 y 2008 en dos numero de larvas y evaluaciones del dan~o a la hoja. En otro experimento, se estimo el impacto de T

Nault, Brian

39

OBRIGATRIAS Disciplina: Urologia  

E-print Network

-Requisito: MC366(ANESTESIOLOGIA, DOR E MEDICINA INTENSIVA), MC365(CIRURGIA GERAL), MC369(ORTOPEDIA E. Abordagem de fraturas expostas e fraturas complexas 6. Controle de danos em ortopedia 7. Tratamento conservador em ortopedia 8. TCE e reabilitação pós trauma 9. Políticas de prevenção no trauma 10.Legislação e

Paraná, Universidade Federal do

40

Energy as Syntax P. Swain, A. Weisse, J. Ollivier, N. Oury  

E-print Network

Energy as Syntax P. Swain, A. Weisse, J. Ollivier, N. Oury (CSBE, Edinburgh), V. Danos, F. Boyde (Independent programmer, Edinburgh), E. Deeds, R. Harmer (Harvard) uRB-AN/IDEA lab project Tuesday, 29 March case of ical caseTuesday, 29 March 2011 #12;- a ring of 2-state protomers P(f): [favoured] f=0=inactive

Edinburgh, University of

41

Screening of Danofloxacin residue in bovine tissue by terbium-sensitized luminescence on C18 sorbent strips  

Technology Transfer Automated Retrieval System (TEKTRAN)

Danofloxacin (DANO) residue in bovine muscle was screened at 200 ng/g by terbium-sensitized luminescence (TSL) directly measured on 10x6 mm C18 sorbent strips. The analyte was first adsorbed on sorbent surface by immersion in defatted homogenates. After reagent application and desiccation, TSL was d...

42

ESTUDO DO EFEITO DO AUMENTO DA CARGA, DA PRESSÃO DE INFLAÇÃO E DO TIPO DE PNEU NA RESPOSTA ELÁSTICA DE UM PAVIMENTO  

Microsoft Academic Search

RESUMO - Neste Trabalho procura-se sintetizar a realidade da área de pavimentação, enfatizando os reduzidos investimentos em obras e pesquisas e a necessidade atual de boas condições de tráfego na rede face a um uso mais intensivo. São arrolados elementos que preocupam os engenheiros e a sociedade sobre os danos aos pavimentos provocados pelo excesso de carga associado a um

João Fortini Albano; Luis Antonio Lindau

43

Spectrofluorimetric Determination of Human Serum Albumin Using Terbium-Danofloxacin Probe  

PubMed Central

A spectrofluorimetric method is proposed for the determination of human serum albumin (HSA) and bovine serum albumin (BSA) using terbium-danofloxacin (Tb3+-Dano) as a fluorescent probe. These proteins remarkably enhance the fluorescence intensity of the Tb3+-Dano complex at 545?nm, and the enhanced fluorescence intensity of Tb3+-Dano is proportional to the concentration of proteins (HSA and BSA). Optimum conditions for the determination of HSA were investigated and found that the maximum response was observed at: pH = 7.8, [Tb3+] = 8.5 × 10?5?mol L?1, [Dano] = 1.5 × 10?4?mol L?1. The calibration graphs for standard solutions of BSA, HSA, and plasma samples of HSA were linear in the range of 0.2 × 10?6 ? 1.3 × 10?6?mol L?1, 0.2 × 10?6 ? 1.4 × 10?6?mol L?1, and 0.2 × 10?6 ? 1 × 10?6?mol L?1, respectively. The detection limits (S/N = 3) for BSA, HSA, and plasma sample of HSA were 8.7 × 10?8?mol L?1, 6.2 × 10?8?mol L?1, and 8.1 × 10?8?mol L?1, respectively. The applicability of the method was checked using a number of real biological plasma samples and was compared with the UV spectrometric reference method. The results was showed that the method could be regarded as a simple, practical, and sensitive alternative method for determination of albumin in biological samples. PMID:22645474

Ramezani, Amir M.; Manzoori, Jamshid L.; Amjadi, Mohammad; Jouyban, Abolghasem

2012-01-01

44

q MUSIC FOR LENT p MUSIC SELECTIONS FOR LITURGIES WITH ORGAN  

E-print Network

DANOS UN CORAZÃ?N 686 III DOMINGO DE CUARESMA MAR 3 CAMINARÃ? 551 EL SEÃ?OR ES COMPASIVO (SALMO 102) 247 WILL KNOW MELLEY THE GLORY OF THESE FORTY DAYS 467 THIRD SUNDAY OF LENT First scrutiny Rite @ 10am MAR 2/3 O LORD, FOR THY TENDER MERCY'S SAKE (10AM) FARRANT WE SHALL RISE AGAIN G 588 FOURTH SUNDAY OF LENT MAR 9

Huang, Jianyu

45

Spectrofluorimetric determination of cefixime using terbium-danofloxacin probe  

PubMed Central

Objective(s): Cefixime (Cfx), is a semi-synthetic third-generation oral cephalosporin antibiotic that is prescribed for the treatment of susceptible infections. There are some procedures for the determination of Cfx in pharmaceutical formulations and biological samples. Herein a spectrofluorimetric method was proposed for Cfx determination based on the fluorescence quenching of terbium-danofloxacin (Tb3+-Dano) in the presence of Cfx. Materials and Methods: Cfx was detected based on fluorescence quenching of terbium-danofloxacin (Tb3+-Dano) in the presence of Cfx with maximum excitation and emission wavelengths at 347 nm and 545 nm, respectively. The quenched fluorescence intensity of Tb3+- Dano system is proportional to the concentration of Cfx. The optimum conditions for the determination of Cfx were studied. Results: The maximum response was achieved under optimum conditions of [Tris buffer]= 0.008 mol/l (pH 6.5), [Tb3+]=1×10-4 mol/l and [Dano]=1×10-4 mol/l. The developed method was evaluated in terms of accuracy, precision and limit of detection. The linear concentration ranges for quantification of Cfx were 8.8×10-8-8.8×10-7 mol/l and 1.1×10-7-8.8×10-7 mol/l in standard and human serum samples with the detection limits (S/N=3) of 2.8×10-8 mol/l and 3.9×10-8 mol/l, respectively. The Cfx was determined in pharmaceutical tablets and spiked serum samples and the results were satisfactory. Conclusion: This method is simple, practical and relatively interference-free for determination of Cfx in pharmaceutical tablets and serum samples. PMID:24904718

Manzoori, Jamshid L.; Amjadi, Mohammad; Soltani, Naser; Jouyban, Abolghasem

2014-01-01

46

Venezuela Paleontolgica Evolucin de la biodiversidad  

E-print Network

. Producción: Printwork Art GmbH, St. Gallen ISBN 978-3-033-03606-2 Copyright © 2012, Marcelo R. Sánchez#12;Venezuela Paleontológica Evolución de la biodiversidad en el pasado geológico Marcelo R contraportada: Stéphane Garcia, Zürich Foto de portada: Arenas de los Médanos de Coro, Foto Marcelo R. Sánchez

Bermingham, Eldredge

47

A Non Parametric Model for the Forecasting of the Venezuelan Oil Prices  

E-print Network

A neural net model for forecasting the prices of Venezuelan crude oil is proposed. The inputs of the neural net are selected by reference to a dynamic system model of oil prices by Mashayekhi (1995, 2001) and its performance is evaluated using two criteria: the Excess Profitability test by Anatoliev and Gerko (2005) and the characteristics of the equity curve generated by a trading strategy based on the neural net predictions. ----- Se introduce aqui un modelo no parametrico para pronosticar los precios del petroleo Venezolano cuyos insumos son seleccionados en base a un sistema dinamico que explica los precios en terminos de dichos insumos. Se describe el proceso de recoleccion y pre-procesamiento de datos y la corrida de la red y se evaluan sus pronosticos a traves de un test estadistico de predictibilidad y de las caracteristicas del Equity Curve inducido por la estrategia de compraventa bursatil generada por dichos pronosticos.

Costanzo, Sabatino; Dehne, Wafaa; Prato, Hender

2007-01-01

48

Overview of crop management strategy for greenhouse tomatoes with an emphasis on employee development  

E-print Network

fruta esta reventada, . La segunda fruta esta pudriendose del lado de abajo. Estos tipos de dano occurren usualmente en plantas viejas 30 Figure 16: Proper knife deleafing Hacemos el deshoje por varias razones, Quitando hojas de las plantas previene... ser frutas reventadas. Este fen6meno ocurre porque la parte interior de la fruta crece mas rapido que la piel del tomate, y la piel se quiebra. Ademas, el deshoje inicia la producci6n de mds frutas nuevas en la planta. Nota. la manera, de deshojar...

Freeman, Christopher Neil

1999-01-01

49

Finding flows in the one-way measurement model  

SciTech Connect

The one-way measurement model is a framework for universal quantum computation in which algorithms are partially described by a graph G of entanglement relations on a collection of qubits. A sufficient condition for an algorithm to perform a unitary embedding between two Hilbert spaces is for the graph G, together with input and output I, O vertices I,O is contained in V(G), to have a flow in the sense introduced by Danos and Kashefi [Phys. Rev. A 74, 052310 (2006)]. For the special case of |I|=|O|, using a graph-theoretic characterization, I show that such flows are unique when they exist. This leads to an efficient algorithm for finding flows by a reduction to solved problems in graph theory.

Beaudrap, Niel de [Institute for Quantum Computing, University of Waterloo 200 University Avenue West, Waterloo, Ontario, N2L 3G1 (Canada)

2008-02-15

50

The Cretaceous-Tertiary boundary biotic crisis in the Basque country  

NASA Technical Reports Server (NTRS)

The Zumaya section has been selected as a classic locality for the study of the Cretaceous-Tertiary (K-T) boundary due to its richness in microfaune, macrofaune, and nannoflora. The sections present similar good conditions for the study of the K-T boundary. The sedimentary rocks of the Uppermost Maastrichtian from the Basque Country are purple or pink marls and marls-tones. Above it is found a clayed bed, 40 to 29 cm thick, grey or dark grey in its basal part, of Lowermost Danian age. Above there is alternation of micritic grey-pink limestones and thin clay beds of Dano-Montian age. The average sedimentation is 7 to 8 times higher during the Upper Maastrichtian than in the Dano-Montian. The macrofauna underwent a decrease since the Campanian and was not found in the last 11 m of the Zumaya section; it was associated with changes in paleoceanographic conditions and primary productivity of the oceans. The microfossil assemblages in the K-T transition allows the recognition of several phases of a complex crisis between two well established planktonic ecosystems. In the Mayaroensis Zone there is a stable ecosystem with 45 to 47 planktonic foraminifera species. The disappearance of A. mayaroensis starts a degradation of the ecosystem. The number of planktonic foraminiera species decreases between 20 and 45 percent. The next phase of the crisis was the result of main extinction events in the planktonic calcareous ecosystem. There are several cretaceous planktonic foraminifera species, probably reworked, whose numbers decrease upward. The next and last phase of the biotic crisis shows a diversification of the ecosystem; the number of planktonic foraminifera is 2 to 3 times higher than before and it is noted the first appearance of Tertiary nannoflora species, while Cretaceous species decrease and persisting species are still the main ones.

Lamolda, M. A.

1988-01-01

51

Detección y estudio mediante Fluorescencia Inducida por Láser de radicales libres formados por Disociación Multifotónica Infrarroja  

NASA Astrophysics Data System (ADS)

Una de las principales aplicaciones actuales de los procesos de disociación multifotónica inducidos por radiación láser infrarroja (DMI) es la producción de radiales libres, con el fin de estudiar sus propiedades cinéticas y espectroscópicas. La disociación de moléculas poliatómicas en el IR con láseres de CO2 tiene lugar desde la superficie de energía molecular mas baja y conduce generalmente a la formación de fragmentos en el estado electrónico fundamental, con diversos grados de excitación vibracional. En el Grupo de Procesos Multifotónicos del Instituto de Estructura de la Materia del C.S.I.C. hemos puesto a punto la técnica de Fluorescencia Inducida por Láser (LIF) para la detección y análisis en tiempo real de los fragmentos producidos en la DMI inducida mediante uno o dos campos láseres de diferentes longitudes de onda. Objetivos de nuestro trabajo han sido el estudio de los canales de disociación mayoritarios y de las especies transitoria producidas, así como de la distribución de energía interna con que éstas son generadas. En particular hemos detectado mediante LIF las especies: C2, CF, CH, SiH2, CF2, CH2, SiHCl, y CF3 a partir de la disociación de, entre otras, las siguientes moléculas: C2H3Br, C3F6, C4H8Si, C2H5ClSi y CH5ClSi. En este trabajo presentamos algunos de los resultados obtenidos mediante el estudio por LIF de estos radicales: estudio temporal de la señal LIF obtenida con determinación de tiempos de vida, espectros de excitación y fluorescencia, temperaturas vibracionales de formación, variación de la intensidad LIF con el tiempo de retraso entre los láseres de disociación y prueba, etc.

Santos, M.; Díaz, L.; Torresano, J. A.; Rubio, L.; Samoudi, B.

52

Open-field host specificity test of Gratiana boliviana (Coleoptera: Chrysomelidae), a biological control agent of tropical soda apple (Solanaceae) in the United States  

SciTech Connect

An open-field experiment was conducted to assess the suitability of the South American leaf feeding beetle Gratiana boliviana Spaeth for biological control of Solanum viarum Dunal in the USA. An open-field test with eggplant, Solanum melongena L., was conducted on the campus of the University of Buenos Aires, Argentina, and a S. viarum control plot was established 40 km from the campus. One hundred adult beetles were released in each plot at the beginning of the experiment during the vegetative stage of the plants, and forty additional beetles were released in the S. melongena plot at the flowering stage. All the plants in each plot were checked twice a week and the number of adults, immatures, and eggs recorded. Results showed almost a complete rejection of eggplant by G. boliviana. No noticeable feeding damage was ever recorded on eggplant. The experiment was ended when the eggplants started to senesce or were severely damaged by whiteflies and spider mites. The results of this open-field experiment corroborate previous quarantine/laboratory host-specificity tests indicating that a host range expansion of G. boliviana to include eggplant is highly unlikely. Gratiana boliviana was approved for field release in May 2003 in the USA. To date, no non-target effects have been observed either on eggplant or native species of Solanum. (author) [Spanish] Una prueba de campo fue conducida para evaluar la especificidad del escarabajo suramericano defoliador Gratiana boliviana Spaeth para control biologico de Solanum viarum Dunal en los Estados Unidos. La prueba con berenjena se realizo en el campo experimental de la Universidad de Buenos Aires, Argentina, y una parcela control con S. viarum fue establecida a 40 km. Cien escarabajos adultos fueron liberados en cada parcela al inicio del experimento durante la fase vegetativa, y cuarenta escarabajos adicionales fueron liberados en la parcela de berenjena durante la floracion. Todas las plantas en cada parcela fueron inspeccionadas dos veces a la semana y el numero de adultos, larvas, y posturas fueron registrados. Resultados indicaron un casi completo rechazo de la berenjena por G. boliviana. Ningun dano visible de defoliacion en la berenjena fue detectado. Las pruebas concluyeron cuando las plantas de berenjena alcazaron su madurez o fueron severamente danadas por mosca blanca y acaros. Resultados corroboran previas pruebas de especificidad en laboratorio/cuarentena que indican que la berenjena no es un hospedero de G. boliviana y que la posibilidad de llegar a ser una plaga de este cultivo es muy remota. Gratiana boliviana fue aprobado para ser liberado en el campo en mayo del 2003. Ningun dano ha sido observado hasta la fecha a plantas no blanco. (author)

Gandolfo, D.; McKay, F. [USDA-ARS South American Biological Control Laboratory, Hurlingham (Argentina); Medal, J.C.; Cuda, J.P. [University of Florida, Department of Entomology and Nematology, Gainesville, FL 32611 (United States)

2007-03-15

53

A Prospective Study on Time to Recovery in 254 Injured Novice Runners  

PubMed Central

Objectives Describe the diagnoses and the time to recovery of running-related injuries in novice runners. Design Prospective cohort study on injured runners. Method This paper is a secondary data analysis of a 933-person cohort study (DANO-RUN) aimed at characterizing risk factors for injury in novice runners. Among those sustaining running-related injuries, the types of injuries and time to recovery is described in the present paper. All injured runners were diagnosed after a thorough clinical examination and then followed prospectively during their recovery. If they recovered completely from injury, time to recovery of each injury was registered. Results A total of 254 runners were injured. The proportion of runners diagnosed with medial tibial stress syndrome was 15%, 10% for patellofemoral pain, 9% for medial meniscal injury, 7% for Achilles tendinopathy and 5% for plantar fasciitis. Among the 220 runners (87%) recovering from their injury, the median time to recovery was 71 days (minimum ?=?9 days, maximum ?=?617 days). Conclusions Medial tibial stress syndrome was the most common injury followed by patellofemoral pain, medial meniscal injury and Achilles tendinopathy. Half of the injured runners were unable to run 2×500 meters without pain after 10 weeks. Almost 5% of the injured runners received surgical treatment. PMID:24923269

Nielsen, Rasmus Oestergaard; Rønnow, Lotte; Rasmussen, Sten; Lind, Martin

2014-01-01

54

An analysis of the trade-off between spatial and temporal resources for measurement-based quantum computation  

E-print Network

In measurement-based quantum computation (MBQC), elementary quantum operations can be more parallelized than the quantum circuit model by employing a larger Hilbert space of graph states used as the resource. Thus MBQC can be regarded as a method of quantum computation where the temporal resource described by the depth of quantum operations can be reduced compared to the quantum circuit model by using the extra spatial resource described by graph states. To analyze the trade-off relationship of the spatial and temporal resources, we consider a method to obtain quantum circuit decompositions of general unitary transformations represented by MBQC on graph states with a certain underlying geometry called generalized flow. We present a method to translate any MBQC with generalized flow into quantum circuits without extra spatial resource. We also show an explicit way to unravel acausal gates that appear in the quantum circuit decomposition derived by a translation method presented in [V. Danos and E. Kashefi, Phys. Rev. A {\\bf 74}, 052310 (2006)] and that represent an effect of the reduction of the temporal resource in MBQC. Finally, by considering a way to deterministically simulate these acausal gates, we investigate a general framework to analyze the trade-off between the spacial and temporal resources for quantum computation.

Jisho Miyazaki; Michal Hajdušek; Mio Murao

2014-09-29

55

Development of an Immunochromatographic Strip Test for Rapid Detection of Ciprofloxacin in Milk Samples  

PubMed Central

A rapid, simple, and sensitive immunochromatographic test strip has been developed for testing residues of ciprofloxacin (CIP). A specific and sensitive monoclonal antibody (mAb) for CIP was generated by immunizing BALB/c mice with well-characterized CIP-Keyhole limpet haemocyanin. Under the optimized conditions, the cut-off limits of test strips for CIP were found to be 5 ng/mL in phosphate-buffered saline and 2.5 ng/mL in milk samples. Each test can be evaluated within 3 min. The cross-reactivities of the CIP test strip to enrofloxacin (ENR), norfloxacin (NOR), nadifloxacin (NDF), danofloxacin (DANO), pefloxacin (PEX), lomefloxacin (LOME), enoxacin (ENO), and sarafloxacin (SAR) were 71.4%, 71.4%, 66%, 50%, 33%, 20%, 12.5%, and 6.25%, respectively. The data indicate that the method is sensitive, specific, and has the advantages of simplicity and speed, therefore, this test strip is a useful screening method for the detection of CIP residues in milk samples. PMID:25211194

Liu, Liqiang; Luo, Liju; Suryoprabowo, Steven; Peng, Juan; Kuang, Hua; Xu, Chuanlai

2014-01-01

56

First report of the L1014S kdr mutation in wild populations of Anopheles gambiae M and S molecular forms in Burkina Faso (West Africa).  

PubMed

We investigated the occurrence of the L1014F and L1014S kdr mutations in malaria vector populations in Burkina Faso (West Africa). A cross-sectional survey was conducted at 10 sites all located in cotton cultivation areas which are assumed to be the major insecticide resistance selection foci in Burkina Faso. The hot ligation method was used to detect the two kdr mutations in field collected Anopheles gambiae s.l. samples. For the first time in Burkina Faso the L1014S mutation was identified in both M and S forms of An. gambiae s.s. populations collected from the site of Koupela in the central-eastern region at low frequency. Furthermore, the L1014S mutation was also found in one specimen of An. arabiensis collected from the Dano site. The data generated in this study provides additional evidence of the spread of the L1014S mutation into An. gambiae s.l. populations in West Africa. It is now important to evaluate the role of the L1014S mutation in the pyrethroid resistance phenotype and assess its potential impact on the efficacy of pyrethroid-based control measures in West Africa where several resistance mutations now coexist. PMID:23128044

Namountougou, Moussa; Diabaté, Abdoulaye; Etang, Josiane; Bass, Chris; Sawadogo, Simon P; Gnankinié, Olivier; Baldet, Thierry; Martin, Thibaud; Chandre, Fabrice; Simard, Frédéric; Dabiré, Roch K

2013-02-01

57

"Estudio tribologico de aceros para moldes. Aplicacion al moldeo por inyeccion de polibutilentereftalato reforzado con fibra de vidrio"  

NASA Astrophysics Data System (ADS)

Mould materials for injection moulding of polymers and polymer-matrix composites represent a relevant industrial economic sector due to the large quantity of pieces and components processed. The material selection for mould manufacturing, its composition and heat treatment, the hardening procedures and machining and finishing processes determine the service performance and life of the mould. In the first part of the present study, the relationship between the hardness and microstructure and the wear resistance of mould steels from large blocks has been studied by pin-on-disc tests, studying the main wear mechanisms. In order to determine the surface damage on mould steels under real injection conditions, different commercial steels have been studied by measuring the variation of surface roughness with the number of injected pieces with different reinforcement percentages and different mould geometries, by using optical profilometry and scanning electron microscopy techniques. It was important to determine the variation of surface roughness of the moulded pieces with the number of injection operations. The materials used were polybutyleneterephthalate pure and reinforced with either 20% or 50% glass fibre. For the different mould designs, the evolution of the glass fibre orientation with injection flow has been determined by image analysis and related to roughness changes and surface damage, both of the composite parts and of the mould steel surface. Finally, the abrasion resistance of the composite parts has been studied by scratch tests as a function of the number of injected parts and of the scratch direction with respect to injection flow and glass fibre orientation. Los materiales para moldes de inyeccion de polimeros y materiales compuestos representan un sector economicamente muy relevante debido al gran aumento del numero de componentes fabricados a partir de materiales polimericos obtenidos mediante moldeo por inyeccion. La seleccion del material para la fabricacion del molde, tienen una gran influencia sobre su comportamiento en servicio a lo largo de la vida util del molde. En la primera parte del presente estudio, a partir de ensayos punzon sobre disco, se ha determinado la relacion entre la resistencia al desgaste y la dureza de aceros para moldes obtenidos a partir de bloques de gran espesor, estudiando los principales mecanismos de desgaste que tienen lugar. A continuacion, con el fin de determinar el dano superficial que sufren los aceros para moldes en condiciones reales de inyeccion, se han estudiado distintos tipos de aceros utilizados comercialmente en moldes de inyeccion de polimeros y materiales compuestos, seleccionando las condiciones de operacion para determinar la variacion de la rugosidad superficial del acero en funcion del material inyectado, del numero de operaciones sucesivas de inyeccion y de la orientacion del flujo de inyeccion, mediante tecnicas de perfilometria optica y microscopia electronica de barrido. Ademas del dano superficial sufrido por el acero con el numero de piezas inyectadas, tambien se ha determinado la evolucion de la rugosidad superficial de los materiales inyectados, polibutilentereftalato (PBT) puro y materiales compuestos derivados de PBT por adicion de un 20 o un 50% en peso de fibra de vidrio. En el caso de las piezas inyectadas, se ha caracterizado su microestructura en funcion del flujo de inyeccion y de la densidad de fibra, se han determinado sus propiedades termicas y dinamico-mecanicas, asi como la variacion de la rugosidad superficial de las piezas inyectadas con el numero de operaciones de inyeccion y con la geometria de las distintas secciones de las piezas. Finalmente, se ha evaluado la resistencia a la abrasion de PBT reforzado con un 50% de fibra, en funcion del numero de piezas inyectadas y de la direccion de rayado con respecto a la orientacion del flujo de inyeccion.

Martinez Mateo, Isidoro Jose

58

Simulação de ejeções de massa coronal  

NASA Astrophysics Data System (ADS)

Ejeções de massa coronal (EMC) são bolhas gigantes de gás permeadas por campos magnéticos que são ejetadas do Sol durante um período de várias horas. Caso estas ejeções atinjam a Terra, geralmente, causam uma série de distúrbios às comunicações de longa distância e navegação, além de danos a satélites e transformadores. Portanto, é desejável que sejamos capazes de prever quando estas ejeções atingirão a Terra. Para tanto, é necessário um bom entendimento dos mecanismos causadores das ejeções e, principalmente, de como se dá a propagação das EMC e sua interação com o vento solar que permeia o meio interplanetário. Nesse sentido foi desenvolvido um programa computacional para resolver as equações MHD (Magneto-Hidro-Dinâmica) que regem a evolução das EMC. Primeiramente foram estabelecidas as condições necessárias para descrever o vento solar, no estado estacionário, que permeia todo o meio interplanetário. Num primeiro momento, resolveu-se o sistema de equações para o caso do vento isotérmico, conhecida como a solução de Parker, a fim de testarmos o modelo. Então, foi considerado o caso do vento solar com temperatura variável no meio interplanetário. Este resultado foi utilizado como a base de nosso sistema em seu instante inicial. Posteriormente foram feitas as considerações necessárias para descrever a propagação da Ejeção de Massa Coronal. As EMC foram simuladas como um aumento de densidade e temperatura local na coroa solar. A órbita e a posição da Terra foram incluídas no sistema. Os dados gerados possibilitaram uma análise da evolução da EMC pelo meio interplanetário até encontrar-se com a Terra. Os perfis de densidade e temperatura a 1 Unidade Astronômica são comparados com os dados de satélites reportados na literatura.

Corsini, M. A.; Silva, A. V. R.

2003-08-01

59

Speaking, writing, and memory span in children: output modality affects cognitive performance.  

PubMed

Low-level processes of children's written language production are cognitively more costly than those involved in speaking. This has been shown by French authors who compared oral and written memory span performance. The observed difficulties of children's, but not of adults' low-level processes in writing may stem from graphomotoric as well as from orthographic inadequacies. We report on five experiments designed to replicate and expand the original results. First, the French results were successfully replicated for German third-graders, and for university students. Then, the developmental changes of the cognitive costs of writing were examined during primary school, comparing the performance of second- and fourth-graders. Next, we show that unpractised writing modes, which were experimentally induced, also lead to a decrease of memory performance in adults, which supports the assumption that a lack of graphomotoric automation is responsible for the observed effects in children. However, unpractised handwriting yields clearer results than unpractised typing. Lastly, we try to separate the influences of graphomotoric as opposed to orthographic difficulties by having the words composed through pointing on a "spelling board". This attempt, however, has not been successful, probably because the pointing to letters introduced other low-level costs. In sum, throughout the four years of primary school, German children show worse memory span performance in writing compared to oral recall, with an overall increase in both modalities. Thus, writing had not fully caught up with speaking regarding the implied cognitive costs by the end of primary school. Therefore, conclusions relate to the question of how to assess properly any kind of knowledge and abilities through language production. Los procesos de bajo nivel en la producción de lenguaje escrito en niños son más costosos a nivel cognitivo que los que están implicados en el habla. Esto ha sido demostrado por autores franceses quiénes compararon la ejecución en la capacidad de retención en la memoria oral y escrita. Las dificultades observadas en niños, pero no en adultos, en procesos de bajo nivel en la escritura pueden derivarse de la inadecuación grafomotriz u ortográfica. Informamos sobre cinco experimentos diseñados para replicar y ampliar los resultados originales. Primero, los resultados franceses fueron replicados con éxito para alemanes en tercer curso y para estudiantes universitarios. Después, los cambios evolutivos en costes cognitivos en la escritura fueron estudiados durante la educación primaria, comparando la ejecución de los alumnos del segundo y cuarto curso. Posteriormente, demostramos que las formas de escribir no practicadas, que se han inducido experimentalmente, conducen a la disminución de la ejecución en la memoria también en adultos, lo cual apoya la hipótesis de que la falta de la automatización grafomotriz es la responsable de los efectos encontrados en niños. Sin embargo, la escritura a mano muestra resultados más claros que la escritura a máquina. Por último, hemos intentado separar la influencia de la grafomotricidad frente a las dificultades ortográficas componiendo las palabras señalando en una "pizarra de ortografía". Este intento, sin embargo, no ha tenido éxito, probablemente porque señalar letras ha introducido otros costes de bajo nivel. Resumiendo, a lo largo de los cuatro años de la educación primaria, los niños alemanes muestran peor ejecución en retención en memoria en la escritura, en comparación con el recuerdo oral, con un incremento general en ambas modalidades. Por tanto, al final de la educación primaria, la escritura no ha igualado todavía el habla en cuanto a los costes cognitivos. Por consiguiente, las conclusiones están relacionadas con la cuestión de cómo evaluar cualquier tipo de conocimiento o habilidades mediante la producción de lenguaje. Les processus de bas niveau de la production du langage écrit chez les enfants sont cognitivement plus coûteux que ceux impl

Grabowski, Joachim

2010-02-01

60

Was the 19th Century end of the Little Ice Age in the Alps forced by industrial black carbon?  

NASA Astrophysics Data System (ADS)

Glaciers in the European Alps began to retreat abruptly from their mid 19th century maximum, marking what appeared to be the end of the Little Ice Age. Alpine temperature and precipitation records suggest that glaciers should instead have continued to grow until circa 1910. Our current knowledge of the Alpine climate, climatologists consider the climatic end of the LIA to have come markedly later than the glaciological end, resulting in a paradox. Simulations of glacier length variations using glacier flow and mass balance models forced with instrumental and proxy temperature and precipitation fail to match the timing and magnitude of the observed late 19th century retreat. Matches between simulations and observations have only been achieved when additional glacier mass loss is imposed after 1865 or when precipitation signals are generated that would fit the glacier retreat rather than using actual precipitation records. A known transition however did occur across that half century and into the 20th century that may have held powerful potential consequences for absorption of solar radiation, earlier melt of snow cover, and, in turn, the retreat of glaciers. That transition was the dramatic rise in a byproduct of industrialization: black carbon. Ice cores indicate that BC concentrations increased abruptly at mid 19th century and largely continued to increase into the 20th century, consistent with known increases in BC emissions from the industrialization of Western Europe. We estimate the radiative forcings by these changes in BC loading and whether they were of sufficient magnitude to produce the pronounced negative glacier mass balance that began mid 19th century. Inferred annual surface radiative forcings increased stepwise to 13-17 W m-2 between 1850 and 1880, and to 9-22 W m-2 in the early 1900s, with snowmelt season (April/May/June) forcings reaching greater than 35 W m-2 by the early 1900s. These snowmelt season radiative forcings would have resulted in additional annual snow melting of as much as 0.9 m water equivalent across the melt season. Simulations of glacier mass balances with radiative forcing equivalent changes in atmospheric temperatures result in conservative estimates of accumulating negative mass balances of magnitude -15 m water equivalent by 1900 and -30 m water equivalent by 1930, magnitudes and timing consistent with the observed retreat. These results suggest a possible physical explanation for the abrupt retreat of glaciers in the Alps in the mid 19th century that is consistent with existing temperature and precipitation records and reconstructions. Fig. 3 Atmospheric structure in the Swiss Alps, photo courtesy of Dano Olivieri (www.onyrix.com).

Painter, T. H.; Flanner, M.; Marzeion, B.; Kaser, G.; VanCuren, R. A.; Abdalati, W.

2013-12-01

61

Improving Short Wave Breaking Behavior In Surfbeat Models  

NASA Astrophysics Data System (ADS)

In present surfzone modeling three approaches are widely applied: short-wave resolving models, ‘surfbeat’ models, which resolve wave energy modulations on the time-scale of wave groups and their associated infragravity waves, and wave averaged models. In all three approaches, wave breaking is a process that is highly schematized and governed by several empirical coefficients. In this presentation we will focus on the breaking process in ‘surfbeat’ models, such as XBeach (Roelvink et al, 2009). These models need to describe the short wave dissipation by breaking as a function of the slowly-varying short wave energy or wave height. The model usually applied is that by Roelvink (1993), which combines a probability that waves are breaking as function of wave heigth over water depth ratio H/h with a bore-type dissipation formulation similar to that by Battjes and Janssen (1978). A drawback of such a formulation is that there is no ‘memory’ in the breaking process, and the amount of breaking instantly varies with the water depth (though the wave height itself does have a memory). For cases with bichromatic waves, or for long-period swell, this does not reflect reality enough: waves that start breaking do not instantly stop breaking once the water depth increases, but continue until some lower threshold is reached. This concept was captured in Dally’s (1992) wave-by-wave approach, where individual waves are tracked in a probabilistic setting. We have now implemented a similar formulation in XBeach, where the property that waves are breaking is tracked; it is switched on when H/h exceeds a first criterion; this property is propagated using an advection equation and when H/h gets below a second criterion breaking is switched off. This formulation can do two things the previous one can’t: maintain groupiness inside the surf zone and have a maximum of wave breaking in the trough after a steep bar, as was observed for instance in Arcilla et al’s (1994) test 1C. Obviously this has important consequences for the forcing of both long waves and mean currents. In our presentation we will show results of comparisons of both formulations. References. Arcilla, A.S., Roelvink, J.A., O'Connor, B.A. Reniers, A., and Jimenez. J.A. The Delta Flume '93 Experiment. Coastal Dynamics '94. Arcilla, Stive and Kraus (eds), ASCE, New York, pp. 488-502. Battjes, J.A. and J.P.F.M. Janssen, (1978), Energy loss and set-up due to breaking in random waves, Proc. 16th Int. Coastal Eng. Conf., Hamburg, vol. 1: 569-587. Dally, W.R. (1992) Random breaking waves: Field verification of a wave-by-wave algorithm for engineering application. Coastal Engineering, Volume 16, Issue 4, March 1992, Pages 369-397. Roelvink, Dano, Ad Reniers, Ap van Dongeren, Jaap van Thiel de Vries, Robert McCall, Jamie Lescinski. Modelling storm impacts on beaches, dunes and barrier islands, Coast. Eng. (2009), doi:10.1016/j.coastaleng.2009.08.006 Roelvink, J.A. Dissipation in random wave groups incident on a beach. Coastal Eng., 19 (1993) pp. 127-150.

Roelvink, J.; Daly, C.; Vandongeren, A. R.; van Thiel de Vries, J.; McCall, R.

2009-12-01