471 research outputs found
An Unsung Hero of the Tanner--Jeffrey Subramanian
Jeffrey Subramanian beautifies the grounds surrounding the Tanner Building, but he also writes poetry and plays the cello. The author calls Jeffrey an unsung hero because he is, in fact, the author\u27s hero
Multiscale damage in co-cured composites - Perspectives from experiments and modelling
Bonded and co-cured composites are popular alternatives to structures joined with mechanical fasteners in aircraft but the complex and coupled damage mechanisms in the co-cured/bonded region are poorly understood, thus making the evaluation of their strength and durability difficult with current modelling strategies. This study explores the potential of interleaf inclusion in failure-prone, critical regions of co-cured composite specimens in improving the joint strength and interface fracture toughness and strives to advance the understanding of damage initiation in the co-cured region using an atomistic model. A two-pronged approach is pursued here with bench-scale experimental testing and molecular modelling in this study. Experiments are performed for mode I fracture toughness with double cantilever beam (DCB) on composite laminates with an epoxy interleaf layer. Two epoxy resins and three methods for interleaf inclusion are explored in this study; we supplement the results from DCB testing with insights from confocal microscopy on the crack tip and the interleaf layer pre- and post-testing. Molecular dynamic (MD) simulations capture the cohesive interactions at the threephase interface containing the carbon fiber, the prepreg epoxy, and the interleaf epoxy. Results highlight that an interleaf layer made from partially-cured and filmed epoxy, further consolidated in the composite lay-up is the most effective way to suppress void formation, improve dispersion, and maximize cohesive interactions at the interface of co-cured composites.Aerospace Structures & Computational Mechanic
Bol Processor BP2
Bol Processor 2 (BP2) is a music composition/improvisation software producing arrangements of sound-objects with a set of rules similar to formal grammars. The inference engine produces strings of symbols feeding an algorithm for the expansion of (polymetric) polyphonic/polyrhythmic structures, and ultimately a time-setting algorithm dealing with constraints on sound-objects. First interfaced with MIDI and Csound, BP2 has a great potential for modelling durations and melodic patterns in speech synthesis.Link on SourceForge: http://bolprocessor.sourceforge.netBol Processor 2 (BP2) es uno software de composición y improvisación de música producir arreglos de sonido de objetos con un conjunto de normas similares a las gramáticas formales. El motor de inferencia produce cadenas de símbolos que alimente un algoritmo para la expansión de (polimétrico) polifónicos/polirrítmica estructuras, y en última instancia, un algoritmo de establecimiento de tiempo de hacer frente a las limitaciones en el sonido-objetos. En primer lugar interconectado con MIDI y Csound, BP2 tiene un gran potencial para el modelado de las duraciones y los patrones melódicos en la síntesis de voz.Enlace en SourceForge: http://bolprocessor.sourceforge.netBol Processor 2 (BP2) est un logiciel de composition/improvisation générant des structures d'objets sonores à partir d'un ensemble de règles similaires à celles des grammaires formelles. Le moteur d'inférence produit des chaînes de symboles auxquelles sont appliquées un algorithme d'expansion de structures polyphoniques/polyrythmiques (polymetriques), puis un algorithme de temporalisation utilisant des contraintes sur les objets sonores. Interfacé à l'origine avec MIDI et Csound, BP2 peut être utilisé pour modéliser les durées et les formes mélodiques en synthèse de la parole.Lien sur SourceForge : http://bolprocessor.sourceforge.netBEL, B. Acquisition et représentation de connaissances en musique. Thèse de Doctorat en Sciences (nouveau régime) : Université de Droit, d'Economie et des Sciences d'Aix-Marseille III. Sous la direction de M. Alain Guénoche. Novembre 1990. Paris: EDILIVRES. 2008http://tel.archives-ouvertes.fr/tel-0000969
Tertiary patterns in inclined layer convection
Convection in an inclined layer generates various types of spatio-temporal patterns due to interaction of buoyancy and shear. At small angles of incline, the secondary instability of the uniform base state occurs in the form of buoyancy dominated longitudinal rolls. Above a critical angle of incline marking a co-dimension 2 point, shear driven transverse roll instabilities take over as the secondary instabilities. Computing the location of the co-dimension 2 point for varying thermal driving and inclination angle and determining all secondary bifurcations together with the resulting tertiary states allows to characterize the nonlinear phase diagram of inclined layer convection system. The semi-analytically computed phase diagram quantitatively matches experimental observations by Daniels et al. Close to the co-dimension 2 point, a subcritical secondary bifurcation leading to bistability is identified. In the bistable region, heteroclinic cycles generate bursting behavior
Damage arrest mechanisms in nanoparticle interleaved composite interfaces
The effectiveness of carbonaceous nanoparticles in arresting and delaying damage in nanocomposites has been attributed to multiscale toughening mechanisms. To explore their application in joined interfaces of composites, this study investigates the use of carbon nanotube (CNT) interleaved films for co-cured joining of composite parts and their consequent effects on the interfacial fracture toughness. Carbon nanotubes dispersed in a thermoset resin into thin films of two discrete thicknesses (200 μ and 500 μ) and three concentrations of CNT dispersion were chosen for this study (0.5% wt., 1% wt., and 2% wt.). The films were semi-cured in the oven before being incorporated as interleaves in the composite laminate interface. Fracture toughness of the interface in mode I loading conditions was determined through double cantilever beam (DCB). Micrographs of the fracture surfaces reveal a slip-and-stick based crack jump and arrest phenomena in mode I when nanoparticles are added to the interleaved interface. The thickness of the interleaves has a more significant effect on mode I toughening mechanisms than the concentration of the nanoparticles.Aerospace Structures & Computational Mechanic
Electroactive polymers: synthesis and applications/ Muralisrinivasan Natamai Subramanian
Includes bibliographical references and index"The book focuses on the development of high performance, high efficiency electroactive polymers (EAPs), and electromechanically active polymers by controlling molecular chemical structure and morphology for all applications. This book is ideal for academicians and researchers in polymer and materials science"--Intro -- Preface -- Contents -- About the Author -- Chapter 1 Introduction -- Chapter 2 Polymers -- fundamental -- Chapter 3 Electroactive polymers -- Chapter 4 Electroactive polymers -- synthesis -- Chapter 5 Blends and composites of EAP -- Chapter 6 Characterization of EAPs -- Chapter 7 Electroactive polymers -- applications -- Chapter 8 Electroactive polymers -- challenges -- Chapter 9 Present trends -- Chapter 10 Future trends -- Index1 online resource (213 pages
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Corrigendum to "Metabolites and growth factors produced by Airway epithelial cells induce tolerance in macrophages" [Life Sci. 302 (2022) 120659].
The authors regret the incorrect publication of the name of the co-author ‘Veedamali S Subramanian’ in the original article. The correct name ‘Veedamali S Subramanian’ is updated in the authors list. The authors would like to apologise for any inconvenience caused
Metrocoris dinendrai Basu, Polhemus and Subramanian, NEW SPECIES
Metrocoris dinendrai Basu, Polhemus and Subramanian, NEW SPECIES Figs. 33–44 Material examined. Holotype: Apterous male: INDIA, West Bengal, Darjeeling District, roadside cascades within Neora Valley National Park, 27.0828°N, 88.7437°E, 2006m. asl, 3.X.2012, coll. S. Basu, deposited at the Zoological Survey of India, H.Q., Kolkata (NZSI) Reg. No. 4774/H15. Paratypes: INDIA, West Bengal: 1 apterous male, 1 apterous female, 31 nymphs: same data as holotype Reg. No. 4775/H15; 2 apterous males, 1 apterous female, 1 macropterous female, 5 nymphs, Darjeeling District, stream on the way to Chengey Falls, near Lava, 27.0511°N, 88.6800°E, 1639 m. asl, 3.X. 2012, coll. S. Basu (NZSI) Reg. No. 4776/H15; 4 apterous males, 2 apterous females, 1 nymph, Darjeeling District, stream near Gorubathan, 26.96636°N, 88.7000°E, 370 m. asl., 1.X.2013, coll. S. Basu, (NZSI) Reg. No. 4777/H15. Description. Apterous male (Holotype): Fig.33 Size: Body length 5.42 mm, maximum width across mesoacetabula 2.53 mm. Colour: Dorsal body coloration yellowish to orange with dorsal black markings (Fig. 33). Interocular dark mark rectangular, bifid posteriorly, anterior margin not connected with dark mark of postclypeus, posterior portion in some individuals connected with dark inner margin of eye. Antennal segments black, with first segment yellow basally. Eyes black. Dark marks on pronotum broad T-shaped, connected to propleural margin (Fig.33). Meso- and metanota pale orange with dark markings as in Figs. 33, sublateral dark stripes broader than yellowish part on apical half, longitudinal dark stripe of mesopleuron extending nearly through its length. Abdominal terga black except segment VIII. Thoracic venter black, with a deep yellowish patch laterally (Fig. 36). Abdominal sterna II– VI black, sterna VII–VIII yellowish posteriorly. Fore femur black, basal one-fourth of ventral and dorsal surfaces yellowish, fore tibia and tarsus black. Rostrum black with pale yellowish lateral margins. Structural characteristics: Head width 1.36, length 0.73. Interocular region wider than eye, widths 0.61 and 0.25 respectively. Eye length 0.62, posterior half of eye covering anterior one fourth of propleuron. Length of antennal segments I–IV: 2.29, 0.97, 0.88, 0.65, first segment longer than combined lengths of remainder. Rostrum length 1.46, surpassing fore trochanter. Pronotum slightly bulbous in male, wider than long, width 1.61, length 0.57, slightly wider than head. Meso- and metanota 1.12 times wider than combined length, width 2.55, length 2.27. Fore femur (Fig. 39) slender and slightly curved at middle, ratio of length/width approximately 6.5, ventral surface with small constriction near middle, without indentation or tooth, with short dense hair fringe ventrally near apex, inner margin with rows of short hairs. Inner margin of fore tibia not modified, bearing rows of short hairs. Second tarsal segment long. Pretarsus with pair of sharp claws. Hind trochanter lacking modifications. Abdominal terga with prominent golden pubescence, combined length 1.83, maximum width 1.21. Abdominal sternum VIII bearing long dense hair fringe (Fig. 37). For measurements of leg segments see Table 1. Male genitalia: Male abdominal sternum VIII (Fig. 37) elongate, sub-oval, length 1.27, width 0.86, densely clothed with fringe of golden hairs. Posterior margin of abdominal tergum VIII straight. Pygophore (Fig. 42) elongate, heavily setiferous, apex truncate. Proctiger (Fig. 41) moderately elongate, lateral margins slightly convex, isolating angular basal lobes, apex broadly rounded, posterior margin with dense hair fringe. Parameres symmetrical (Fig.43) strongly curved near midpoint, apical section expanded to small head with outer margin concave, apex blunt, inner and outer margins with long distinct setae, several whitish dots distributed throughout. Endosomal sclerites as in Fig. 44. Apterous female: Fig. 34 Size: Body length 4.41–4.55, maximum width across mesoacetabula 2.29–2.31. Colour: Pattern of dark markings similar to that of male except much wider and more prominent; fore femur slender, lacking median invaginations; sterna VI–VII yellowish. Structural characteristics: Head length 0.74, width 1.21. Length of antennal segments 1–4: 1.87, 0.65, 0.60, 0.72. Eye length 0.61, width 0.24, interocular width 0.66. Length of rostrum 1.45. Pronotum wider than long, length 0.50, width 1.54. Combined lengths of meso- and metanota 2.12, width 2.21. Fore femur length/width ratio 6.3, lacking medial constriction; fore pretarsi bearing sharp, curved claws; hind trochanter lacking modifications. Abdominal sterna II–VI combined length 0.96, maximum width 1.57. For measurements of leg segments see Table 2. Female terminalia: Abdominal sternum VII semi-circular, length 0.30, width 1.07, slightly constricted laterally, clothed with short golden pubescence. Macropterous male: Unknown. Macropterous female: Fig. 35 Size: Body length 5.32, maximum width across mesoacetabula 2.67. Structural characteristics: Golden brown dorsally, marked with prominent black markings as shown in Fig.35. Median length of pronotum 2.41, humeral width 1.72, length of lateral margin from anterior angle to humerus 0.89, length of lateral margin from humerus to apex 1.76, apex of pronotum pointed, medially slightly bulged. Etymology. This name “dinendra” is a patronym dedicated to Professor Dinendra Roychoudhury of Department of Zoology of University of Calcutta, who had encouraged the first author to carry out entomological research. Habitat. This species was collected from high mountainous cascades within the Neora Valley National Park of the Darjeeling District in West Bengal. The insects were found in steep, rocky areas flooded with splashing water, and appear adapted to the cold waters. A preference for rushing, high gradient upland streams has also been observed by the second author (DP) for another currently undescribed species of the Metrocoris compar species group collected in northern Vietnam, suggesting this habitat association may be typical of the group as a whole. Comparative notes. Metrocoris dinendrai sp. nov. belongs to Metrocoris compar group based on the structure of male fore femur, which is slender and slightly curved; the strongly curved male parameres; the elongate male pygophore which bears dense dark pilosity; and the laterally constricted female terminal abdominal sterna. This new species can be recognized within this group by the distinctive shape of male paramere, which has a a slightly expanded apex that is somewhat concave on its outer margin (Fig. 43); the structure of male endosomal sclerites (Fig. 44); and the female trochanter clothed with thick black bristles. Within the Metrocoris compar group, M. dinendrai seems most similar to M. pardus from the Malay Peninsula (Zettel, 2011a), but has the distal arm of the male paramere more slender and elongate, and the outer margin of the paramere apex concave rather than convex (compare Fig. 43 to Fig. 8 in Zettel, 2011a). The basal lobes on the male proctiger also are more angular than in M. pardus, whereas the internal sclerotization of the male endosoma is similar in both species.Published as part of Basu, Srimoyee, Polhemus, D. A., Subramanian, K. A., Saha, G. K. & Venkatesan, T., 2016, Metrocoris Mayr (Insecta: Hemiptera: Gerridae) of India with descriptions of five new species, pp. 257-277 in Zootaxa 4178 (2) on pages 265-267, DOI: 10.11646/zootaxa.4178.2.5, http://zenodo.org/record/25873
The Africa Growth and Opportunity Act and its rules of origin : generosity undermined?
The African Growth and Opportunity Act (AGOA), signed into American law on May 18, 2000, is a major plank of U.S. initiatives toward the African continent. The Act aims broadly at improving economic policymaking in Africa, enabling countries to embrace globalization, and securing durable political and economic stability. As an incentive for Africa to adopt the necessary policy reform, AGOA offers increased preferential access for African exports to the United States. This paper describes the provisions of AGOA and assesses its quantitative impact on African exports, particularly in the apparel sector. Its main conclusions are: 1) AGOA will provide real opportunities to Africa. Even on conservative estimates about Africa's supply response, Africa's non-oil exports could be increased by about 8-11 percent. 2) However, the medium-term gains could have been much greater if AGOA had not imposed certain conditions and not excluded certain items from its coverage. The most important condition is the stringent rule-of-origin, that is, the requirement that exporters source certain inputs from within Africa or the United States. Estimates suggest that the absence of these conditions would have magnified the impact nearly five-fold, resulting in an overall increase in non-oil exports of US100-US$140 million increase that is expected in the presence of these restrictions. These restrictions, particularly on apparel, will come at a particularly inopportune time, as Africa will be exposed to competition from other developing countries when the quotas maintained on the latters'exports under the Multi-Fiber Arrangement (MFA) are eliminated. Africa's apparel exports will be lower by over 30 percent with the dismantling of the MFA. If, on the other hand, AGOA had provided unrestricted access, the negative impact of the dismantling could be nearly fully offset.Export Competitiveness,Economic Theory&Research,Trade Policy,Environmental Economics&Policies,Agribusiness&Markets,TF054105-DONOR FUNDED OPERATION ADMINISTRATION FEE INCOME AND EXPENSE ACCOUNT,Economic Theory&Research,Environmental Economics&Policies,Export Competitiveness,Trade Policy
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