bluuebunny/crossref_metadata_2025 huggingface dataset:
Posttraumatic Headache
Authors: Langdon Raquel , Taraman Sharief
Published: February 2018

After sustaining a concussion or mild traumatic brain injury, headaches are one of the most common complaints. The pathophysiologic changes that occur in the setting of injury likely contribute to or cause posttraumatic headaches. Posttraumatic headaches often present as migraine or tension-type headaches. Unlike pain from other types of injuries, headaches following mild traumatic brain injury are more likely to persist. Preexisting conditions such as migraine and mood disorders may influence posttraumatic headache and complicate management. Patients are at high risk to overuse abortive medications and develop medication overuse headache. Headache hygiene and early education are essential for effective management. Abortive medications include nonsteroidal anti-inflammatory drugs and triptans. Preventive medications include tricyclic antidepressants and antiepileptics. Patients who fail outpatient therapies may benefit from referral for intravenous medications in the emergency department. Patients with persistent posttraumatic headache may benefit from multimodal treatments including physical rehabilitation and pain-focused cognitive-behavioral therapies.

[
Pediatr Ann.
2018;47(2):e61–e68.]
Histoire de l’art, histoire de l’architecture et histoire des techniques (Europe, xve-xviiie siècle)
Authors: Nègre Valérie
Published: February 2018

L’article examine plusieurs orientations communes aux spécialistes de l’art, de l’architecture et des techniques de la période moderne (xve-xviiie siècle), en particulier trois questions qui sont au cœur des recherches récentes : les interactions entre théories et pratiques, la dimension matérielle de l’invention et la place de la matière comme clé de compréhension de la technique. Il souligne la forte implication des praticiens (conservateurs, restaurateurs, architectes et ingénieurs) dans l’histoire technique de l’art et l’histoire de la construction.
Mechanics of patronage: Christopher Polhem and the changing regimes of the Swedish state (1680-1750)
Authors: Orrje Jacob
Published: February 2018

Cet essai traite des politiques liées à la technologie pendant la période moderne à partir du mécanicien suédois Christophe Polhem. Durant la monarchie absolue du début du xviiie siècle, Polhem obtient avec succès un patronage royal. Mais sous la monarchie constitutionnelle des années 1720, ses relations royales deviennent problématiques. À partir de Polhem, cet article vise à montrer l’ironie de la manière dont certains mécaniciens, présentés comme de fidèles sujets de l’ordre de la première modernité, ont été considérés comme des agents de changements.
Olivier de Serres et son Théâtre d’agriculture
Authors: Vérin Hélène
Published: February 2018

Olivier de Serres a ouvert la voie de la science agricole moderne et de la sériciculture en France. Son important ouvrage, Le Theatre d’agriculture et mesnage des champs, publié en 1600, appartient à une double tradition : celle des écrits sur l’agriculture et celle des écrits sur les arts de la Renaissance. Après une présentation de l’auteur, nous nous attacherons à inscrire cette œuvre dans le contexte de ces traditions. Une dernière partie sera centrée sur la littérature consacrée à l’élevage des vers à soie durant la Renaissance en Europe.
Inventer une technique scripturaire au xviiie siècle : la « Chorégraphie ou l’art de décrire la dance »
Authors: Glon Marie
Published: February 2018

Cet article tâche de cerner « l’invention » dans une technique scripturaire : la « Chorégraphie ou l’art de décrire la dance », dont les principes sont publiés en 1700. Il s’agit de cerner les modalités d’invention de cette nouvelle technique, mais aussi ce que ces modalités d’invention suscitent en termes d’activités et de reconfigurations sociales. Ainsi, l’influence de la géométrie conduit à développer une écriture qui inclut aussi une dimension dessinée, ce qui permet à des acteurs situés hors du champ de l’écriture de se saisir de cette activité scripturaire. Il apparaît également que l’invention de cette technique réside non seulement dans la conception d’un système de signes, mais dans une activité de publication, impliquant de nombreux maîtres de danse. Ce faisant, ces derniers s’insèrent dans le monde de l’imprimé, se revendiquent en tant qu’auteurs et reconfigurent leurs activités. Il s’agit donc de penser la façon dont s’invente une technique, mais aussi la façon dont une technique permet la réinvention d’un métier et la création d’un nouveau réseau d’échanges, à l’échelle de l’Europe.
Tracer le monde : outils et instruments de la Renaissance aux Lumières
Authors: Millet Audrey
Published: February 2018

Du xvie au xviiie siècle, les scientifiques, les techniciens et les pouvoirs veulent mesurer et représenter le monde plus précisément. Cette mise en ordre passe par l’amélioration des instruments de transcription. Les ingénieurs, astronomes, mathématiciens ont en commun le dessin et les instruments. Plumes à dessiner, compas et équerres sont constamment améliorés. Derrière le caractère pratique et technique des instruments, se cache l’ambition des élites. Elles cherchent à rayonner au sein d’une société convertie aux innovations. Elles montrent aussi leur foi en l’universalité des connaissances.
La Tour de Londres au xviie siècle, un lieu de savoir
Authors: Ruellet Aurélien
Published: February 2018

La Tour de Londres, complexe fortifié situé sur la rive nord de la Tamise, abrite depuis la fin du Moyen Âge une prison, mais aussi des services techniques comme l’Artillerie ou la Monnaie. Au xviie siècle, la forteresse constitue un « lieu de savoir » où dialoguent différentes traditions intellectuelles et techniciennes et où circulent les individus qui les portent.
Technology and technical knowledge in the debate about the “great divergence”
Authors: Popplow Marcus
Published: February 2018

À la recherche des raisons pour lesquelles l’industrialisation apparaît d’abord en Europe plutôt que dans d’autres régions du monde, la technologie est souvent considérée comme un facteur prépondérant. Pourtant, les comparaisons restent souvent centrées sur les inventions spectaculaires et les performances quantifiables, perpétuant ainsi des catégories européocentrées. Cet article critique cette perspective de la recherche. En s’intéressant au problème du savoir technique, il propose d’enquêter sur les multiples aspects de l’expertise technique quelles que soient les régions du monde, plutôt que de poursuivre dans la perspective traditionnelle de l’application de la « science » aux problèmes techniques.
Religion and technological development in China and Europe between about 700 and 1800
Authors: Davids Karel
Published: February 2018

Le développement technique a de plus en plus divergé entre Chine et Europe après 1500. Cet article soutient qu’on ne peut pas seulement expliquer cette divergence par des variables économiques comme les prix du combustible et de la main-d’œuvre. Sont également intervenues des variations dans les contextes religieux en Chine et en Europe. Mais, contrairement aux considérations de nombreux historiens et théologiens, le facteur-clé ne peut pas être trouvé dans les différences de croyances et de valeurs dans les traditions religieuses. Plus pertinentes ont été les différences dans l’influence des institutions religieuses et dans le rôle des communications et des mouvements de personnes imputables aux traditions religieuses. Ces aspects de la religion ont contribué à des disparités dans la formation des hommes, la circulation des connaissances et l’innovation technique entre Chine et Europe qui se sont manifestées après 1500.
Les cabinets de physique des rois du Portugal (xviiie-xixe siècles)
Authors: Felismino David , Lourenço Marta C.
Published: February 2018

L’histoire des cabinets royaux de physique portugais est mal connue. Les vastes collections d’instruments scientifiques qui les composaient, organisées au cours des xviiie et xixe siècles, ainsi que d’importantes bibliothèques et collections d’histoire naturelle destinées à l’éducation des jeunes Infants et au divertissement de la cour, ont presque intégralement disparu. Dans de nombreux cas, leur mémoire n’a survécu qu’à travers un petit nombre d’inventaires, de récits d’aristocrates de l’époque et de quelques voyageurs étrangers de passage à Lisbonne.Les collections du cabinet royal de physique, organisées en forme systématique et enrichies par le mathématicien vénitien Michel Franzini (c. 1740-1810) durant les trois dernières décennies du xviiie siècle, ont été progressivement démontées et éparpillées, au cours du xixe siècle, avec l’émergence des institutions universitaires, polytechniques et militaires et, à partir de 1910, avec l’avènement de la République et la nationalisation des biens royaux. Celles-ci avaient déjà subi les conséquences de leur transfert au Brésil (1807-1821) et de l’occupation et de la confiscation françaises (1807-1810).Une étude récente menée au sein des collections des musées techniques et universitaires, des institutions d’enseignement, ainsi que des anciennes résidences royales, a permis de faire ressurgir de nombreux instruments ayant appartenu aux collections royales. Ces objets d’origine diverse (Angleterre, Allemagne, Pays-Bas, France, Italie, Portugal) et de nature hétéroclite (physique, chimie, astronomie, mathématique, etc.) contribuent à mieux faire connaître et comprendre les cabinets de physique des monarques portugais. Cet article présente, sous une forme succincte, les résultats de cette recherche, en discutant plusieurs aspects de la formation et de la dispersion, de la provenance et de la « muséalisation » des cabinets.
Les vicissitudes d’une collection d’objets techniques au xixe siècle : le cabinet des machines de la Société d’encouragement pour l’industrie nationale
Authors: Sauvalle Chloé
Published: February 2018

Le 1er novembre 1801, a lieu l’assemblée générale constitutive de la Société d’encouragement pour l’industrie nationale, qui se propose de devenir un centre d’expertise scientifique et technique ouvert sur le monde des savants, des ingénieurs, des artistes, des artisans, des industriels ou encore des manufacturiers. Elle se donne pour mission de recevoir les inventions qui lui sont apportées, de les expérimenter et d’assurer la diffusion des nouveaux procédés ainsi mis au point. Ayant pour vocation l’encouragement et étant chargée d’examiner de nouveaux procédés, l’institution se doit de conserver des ouvrages techniques, des modèles et des machines. Pour répondre à ce besoin, elle se dote d’un cabinet des machines.Il s’agit ici d’en restituer l’histoire, de sa constitution à sa fermeture. Deux axes permettent d’éclairer l’histoire de ce cabinet des machines. Tout d’abord l’histoire propre de la Société d’encouragement mettant en avant les difficultés, souvent d’ordre pratique, de la collecte et de la conservation d’objets et de machines, puis le parcours même de certains de ces objets qu’il est possible de retracer.
Missions commerciales et collections techniques au xixe siècle : l’introuvable « musée chinois » de la mission de Chine
Authors: Demeulenaere-Douyère Christiane
Published: February 2018

En 1843, le diplomate français Théodore de Lagrené s’engage dans un long voyage qui le conduit en Chine, pays qui s’ouvre alors au commerce avec l’Occident. Il emmène quatre délégués de l’industrie française, désignés par les chambres de commerce, dont la mission est de recueillir sur le terrain non seulement des informations commerciales et des contacts, mais aussi des échantillons de matières premières et de produits finis, des outils et des savoir-faire. L’un d’eux, Isidore Hedde, réunit une très importante collection d’échantillons et d’objets en relation avec l’industrie de la soie.À leur retour en France, les objets rapportés font l’objet de plusieurs expositions publiques. Mais, dans un temps qui méconnaît les musées ethnologiques et les musées commerciaux, et en raison des difficultés politiques et économiques du milieu du siècle, le « musée chinois » de la mission de Chine ne verra pas le jour. Il est voué à la dispersion. L’article traite de la constitution de ces collections techniques sur le terrain, de leur(s) statut(s) en France et finalement de leur dispersion actuelle.
La présence française dans la formation des ingénieurs américains durant les deux premiers tiers du xixe siècle : aspects institutionnels et intellectuels
Authors: Chatzis Konstantinos , Preveraud Thomas
Published: February 2018

Aux États-Unis, dans les deux premiers tiers du xixe siècle, la présence française dans la formation des ingénieurs s’exerce tant au niveau institutionnel qu’intellectuel. Les nombreuses institutions dans lesquelles les ingénieurs américains sont instruits s’inspirent largement des structures et méthodes d’enseignement des écoles françaises, ainsi qu’elles importent puis traduisent des manuels français pour l’enseignement de la mécanique théorique. Cependant, ce transfert, qui croise les contextes locaux de l’enseignement supérieur américain et les besoins domestiques des auteurs-professeurs, est soumis à un important travail d’adaptation menant, à la fin du siècle, au spectacle d’un pays dont la formation en matière d’ingénierie s’impose sur la scène mondiale de la technique.
Necropoli dell’Isola Sacra. Le ricerche 1968-89 : ripercorrendo un’esperienza
Authors: Baldassarre Ida , Bragantini Irene , Dolciotti Anna Maria , Morselli Chiara , Taglietti Franca
Published: February 2018

L’articolo ripercorre metodi, problematiche e risultati delle ricerche condotte nella necropoli dell’Isola Sacra (1968-1989) sotto la direzione di I. Baldassarre, con lo scopo di giungere a una lettura in chiave antropologica di una necropoli romana di età imperiale a partire dalla documentazione archeologica. La necropoli si sviluppa ai due lati di una strada (seconda metà del I sec. d.C.) alla quale le tombe fanno riferimento con una costante ricerca di visibilità. Lo studio ha permesso di ricostruire modi e tempi dell’occupazione dello spazio funerario da parte delle singole tombe che si addossano le une alle altre creando l’immagine di edificazioni per gruppi unitari. Si tratta di tombe familiari, la cui funzione risulta dall’apparato epigrafico, dai dispositivi per i rituali funerari, dalla scarsità di materiali di corredo, che appaiono piuttosto in relazione a sepolture individuali, più « povere », che affollano tutti gli spazi liberi tra le tombe a cella. La ricerca ha anche messo in luce il ruolo chiave degli apparati figurativi e lo strutturarsi di un repertorio di decorazione funeraria, tema di particolare interesse per il ceto libertino che seppellisce nella necropoli. Nel quadro del crescente interesse per l’ideologia funeraria romana e riproponendo la storia di una ricerca nata molti anni fa in una Università piena di stimoli, l’articolo intende evidenziare quanto un contesto affrontato nella sua globalità possa contribuire ad approfondire la discussione relativa a questi temi.
Sepolture e monete : il prezzo dell’Ade ? A proposito dei rinvenimenti monetali in tombe della necropoli di Porto all’Isola Sacra
Authors: Camilli Luciano , Taglietti Franca
Published: February 2018

Attraverso l’analisi delle monete rinvenute nella necropoli dell’Isola Sacra durante le campagne di scavo condotte dall’équipe di ricerca delle Università di Roma – La Sapienza e di Napoli – L’Orientale dal 1973 al 1989, viene esaminata la pratica di deporre moneta entro la tomba al fine di individuare le diverse funzioni che la moneta può rivestire in questo contesto e più in generale in ambito sepolcrale (obolo di Caronte, offerta, segno di status, amuleto o talismano). Il materiale numismatico si colloca per lo più nei primi due secoli dell’impero con una forte concentrazione in età antonina, conformemente alla cronologia di uso della necropoli ; sono utilizzati i nominali più bassi del sistema monetario che in generale sembrano tratti dalla coeva moneta circolante : si segnala l’inusuale presenza abbondante di quadranti.
Lo studio antropologico delle sepolture di Larcius Felix ed Onesime
Authors: Nava Alessia , Rossi Paola Francesca , Sperduti Alessandra , Bondioli Luca
Published: February 2018

Nello studio dei contesti a cremazione, l’integrazione tra dato archeologico e antropologico permette una più completa caratterizzazione del defunto e una più nitida lettura dei « gesti funerari » che hanno preceduto/accompagnato la sua sepoltura. Le due urne ostiensi di Larcius Felix e di Onesime rappresentano, da questo punto di vista, un eccezionale rinvenimento, in quanto la presenza delle epigrafi – che identificano il genere e l’età di morte degli individui contenuti negli ossuari – ha dato modo di verificare le stime biologiche ottenute dalle analisi dei resti cremati. Inoltre, i dati registrati nel corso del microscavo delle urne, le osservazioni tafonomiche e le valutazioni sul grado di rappresentatività dei singoli distretti scheletrici hanno consentito di ricostruire alcuni aspetti del rituale.
Il nuovo mitreo dei marmi colorati sulla via della Marciana a Ostia Antica
Authors: David Massimiliano
Published: February 2018

Le indagini svolte nel quartiere fuori porta Marina cominciano ad offrire il quadro evolutivo non solo del paesaggio costiero, ma anche delle forme dinamiche di un’urbanizzazione che si snoda dal I secolo a.C. fino al IV secolo d.C. Questo stesso suburbio si trasformò alla fine del IV secolo in uno di quei luoghi sordidi citati da una ben nota iscrizione, dove edifici prestigiosi come il sontuoso edificio studiato da G. Becatti o le terme della Marciana convivevano con oscure officine e remoti luoghi di incontro. In questo contesto una caupona, progettata e costruita ex novo alla metà del III secolo, venne ristrutturata e adattata alle esigenze di una comunità mitraica. L’edificio, denominato Mitreo dei marmi colorati, si dotò di una particolarissima aula cultuale con pavimentazione marmorea e pareti intonacate e dipinte ad imitazione di raffinati marmi. L’interpretazione e la raffinazione della cronologia dell’edificio sono resi particolarmente complessi non solo dai caratteri di unicità del monumento, ma anche dal particolare meccanismo di formazione della stratigrafia in larga parte condizionata dal cantiere di spoliazione ivi impiantato dopo il Mille.
Un Capricorno ad Ostia (anzi due)
Authors: Nucci Roberta Geremia
Published: February 2018

Questo contributo prende le mosse da una recente scoperta : la presenza, nella decorazione frontonale del tempio di Roma e Augusto a Ostia, di due figure di Capricorni, che sono ricostruiti in maniera alternativa da quella finora proposta. Si esamina quindi in breve la bibliografia relativa ai motivi della scelta del Capricorno come segno zodiacale di Augusto, illustrandone tutte le caratteristiche che lo rendono il segno più adatto a quel momento storico. A tale fine sono indagati sia gli aspetti più genericamente astrologici sia quelli più puntualmente politici e dinastici, che in questo ambito sono di maggiore interesse. Nella seconda parte, si propone una datazione più circostanziata del tempio, che può contribuire, nonostante l’assenza di dati epigrafici, a sfatare alcune credenze sulla datazione del culto imperiale fuori dell’Vrbs. In tale ottica il tempio ostiense assume, all’interno degli edifici per il culto imperiale, un ruolo importante sia per la precocità del suo impianto, sia per l’elaborazione di alcuni modelli formali ed iconografici di grande impatto e successivo sviluppo.
Development & Characterization of Alumina Coating by Atmospheric Plasma Spraying
Authors: Sebastian Jobin , Scaria Abyson , Kurian Don George
Published: February 2018

Ceramic coatings are applied on metals to prevent them from oxidation and corrosion at room as well as elevated temperatures. The service environment, mechanisms of protection, chemical and mechanical compatibility, application method, control of coating quality and ability of the coating to be repaired are the factors that need to be considered while selecting the required coating. The coatings based on oxide materials provides high degree of thermal insulation and protection against oxidation at high temperatures for the underlying substrate materials. These coatings are usually applied by the flame or plasma spraying methods. The surface cleanliness needs to be ensured before spraying. Abrasive blasting can be used to provide the required surface roughness for good adhesion between the substrate and the coating. A pre bond coat like Nickel Chromium can be applied on to the substrate material before spraying the oxide coating to avoid chances of poor adhesion between the oxide coating and the metallic substrate. Plasma spraying produces oxide coatings of greater density, higher hardness, and smooth surface finish than that of the flame spraying process Inert gas is often used for generation of plasma gas so as to avoid the oxidation of the substrate material. The work focuses to develop, characterize and optimize the parameters used in Al2O3 coating on transition stainless steel substrate material for minimizing the wear rate and maximizing the leak tightness using plasma spray process. The experiment is designed using Taguchi’s L9 orthogonal array. The parameters that are to be optimized are plasma voltage, spraying distance and the cooling jet pressure. The characterization techniques includes micro-hardness and porosity tests followed by Grey relational analysis of the results
Dry Sliding Wear Behavior of Titanium Metal Powder Filled Aluminum Alloy Composites for Gear Application
Authors: kumar ashiwani , Patnaik Amar , Bhat I.K.
Published: February 2018

In the current research work, the influence of titanium metal powder on wear beheviour of Al 7075 composites is investigated. These composites were fabricated by using the high vacuum casting machine. The Tribological beheviour of titanium metal powder aluminum alloy composites was investigated by performing dry sliding experiments as a function of wear with a E-31 harden steel disk( 62 HRC) as the counterpart on pin on disk machine . Wear experiments were performed for normal load of 20, 35, 50 , 65 and 80 N at sliding velocities of 0.25, 0.5, 0.75, 1, 1.25 m/s and sliding distance (250 ,500, 750, 1000 and 1250 m at room temperature. The tests were performed on Taguchi’s L25 orthogonal array and the effect of working parameters on wear rate was studied using ANOVA. To investigate the dominant sliding wear mechanism for different steady state experiment conditions, the SEM micrograph of worn surfaces were analyzed using scanning electron microscopy. The wear rate was found to minimum as compared to unfilled alloy and the wear resistance improves the aluminum alloy composites. Finally, it was investigated that the analysis of microstructure and wear properties of titanium metal powder filled alloy composite.
Biosorption of Basic Textile Dye from Aqueous Solution Using Pongamia pinnata as Adsorbent
Authors: Gunturu Bhargavi , Ramakrishnan Geethalakshmi , Sahadevan Renganathan
Published: February 2018

In the present study, the efficiency of biosorbent derived form Pongamiapinata to remove a basic textile dye Methylene Blue from an aqueous solution was evaluated in batch system. The influence of adsorption parameters such as biosorbent dosage (0.2-1.0g/L), PH (2-10) and initial dye concentration (30-110 mg/L) on the biosorption process was studied. It was noticed that adsorbent dosage has negative effect on dye uptake, could be due to reduced mass transfer rate of dye on to adsorbent. High equilibrium uptake was observed at PH 8. However, initial dye concentration has shown linear relationship with dye uptake. As the dye concentration increases, the number of dye molecules available to be adsorbed on to adsorbent surface increases. Equilibrium isotherms for the adsorption of methylene blue was analyzed through Langmuir and Freundlich isotherm models. The data best fit with Freundlich model than Langmuir isotherm model, suggesting the adsorption was by multilayer mechanism. Maximum adsorption capacity (Q ̊) was found to be 40.49mg/g. It can be concluded from the study that the adsorbent derived from P.pinnata can be a potential low cost competent of activated carbon for textile dyes removal.
Improving Mechanical Properties of Dissimilar Material Friction Welds
Authors: Cheepu Muralimohan , Muthupandi V. , Che Woo Seong
Published: February 2018

Friction welding of stainless steel to titanium with aluminum insert metal was investigated to improve the mechanical properties of the joints. Two different methods were used to insert the aluminum as a barrier between to substrates. The process parameters were found to be different for these two methods to obtain the sound welds. The friction welds between stainless steel and titanium with aluminum insert prevented the formation of brittle intermetallic compounds in the weld interface. A new intermetallic compounds such as AlTi and Al3Ti were formed between titanium and aluminum insert metal interface which are more ductile than the FeTi and CrTi intermetallic compounds. The joints characterized that the aluminum insert metal improved the metallurgical reaction at the weld interfaces thus indicates the results of decrease in microhardness of the intermetallic compounds which have major influence on the strength of the joints. The tensile strength of the aluminum insert welds was higher than the direct joints between the stainless steel and titanium. Higher tensile properties were attained at higher upset pressure condition due to the effect of higher force upon the welded materials and the remnant narrower thickness of insert metal.
Influence of Water Cooling and Post-Weld Ageing on Mechanical and Microstructural Properties of the Friction-Stir Welded 6061 Aluminium Alloy Joints
Authors: Venkateswarulu Devuri , Cheepu Muralimohan , Krishnaja Devireddy , Muthukumaran S.
Published: February 2018

A 6061-T6 aluminium alloy was friction stir welded in submerged water as well as in air cool at a constant traverse speed and different rotational speed in order to investigate the microstructural characterization and mechanical behaviour of the joints. In order to improve the tensile strength of the joints, weldments were studied at different heat treatment processes such as post weld aged condition and solutionized condition. It is observed that, water cooled joints are resulted in enhancing of both strength and ductility with the lower strain hardening ability than the air cooled joints. The width of the hardness distribution varies with the different cooling process of the joints. The highest hardness peak observed to be located in the heat affected zone of the joints. The maximum tensile strength of the joints achieved for welds under water cooled conditions in contrast to air cooled conditions. Moreover, a combination of water cooling and post weld ageing is proven to be the optimal path to improving the microstructural and mechanical properties of the joints with a maximum efficiency of 89.87% of the base metal strength. The microstructural observations of the joints revealed the presence of voids defects for the low rotational speed joints due to the insufficient heat input. The nugget of the higher tensile strength joints were free from defects and showed the fine grained material flow patterns which are constructive to obtain better mechanical properties.
Evaluation of Deformation Modulus for the Jointed Rock Masses Using Equivalent Continuum Approach
Authors: Khanna Rahul , Sayeed Imran , Dubey Rajendra Kr.
Published: February 2018

The rock masses are intercepted by several geological discontinuities that make them different from other engineering materials. The response of rock masses during excavation of ground for development of large engineering structures such as dams, tunnels, underground caverns etc. is very complicated. As the engineering structures are significantly larger than the rock blocks with discontinuities, therefore the rock masses may be represented in form of an equivalent continuum. Rock masses in this form are being utilized to determine important engineering properties such as compressive strength and modulus of deformation by means of empirical relationships. These properties have been used as an alternative for in-situ testing for designing of engineering structures. This paper evaluates the deformation modulus (Ed) of jointed rock masses by means of various available relationships for three rock types namely metavolcanics, dolomite and slate occurring extensively in Lesser Himalayan region of northern India. The determined empirical results are validated with the field investigation outputs. An attempt has also been made to work out new empirical relationships based on the field results.
Horizontal Pullout Capacity of a Group of Two Vertical Square Anchors Embedded in Medium Dense Sand
Authors: RAJU K V S B , Pankaja B.S.
Published: February 2018

In the present study an attempt is made to evaluate the ultimate horizontal pullout capacity of group of two square anchors embedded in medium dense sand by conducting laboratory model tests. The size of the model box used in the present study is 1.2m lengthx0.75m width and 1.5m height. A series of experiments were conducted on single and group of anchors subjected to horizontal pullout load on mild steel square plates of size 10 cm and 15 cm were used .Clean dry local river sand was used in the present study. All the tests were carried out on dry clean sand with a relative density of 55% corresponding to medium dense state. The raining technique was adopted to prepare the sample in the model box to achieve the desired density. In the present study the ratio of H/B is equal to 5 and 6; where H = depth of embedment from top of tank to bottom of lower anchor, B=width of anchor. The parameter S/B is equal to 0,1,2; where S = clear spacing between the anchor, and B= width of anchor. It was found from the present study as H/B ratio increases the pull out capacity increases and also for each H/B ratio as the S/B ratio increases pull out capacity decreases due to decrease in passive resistance. In the present study the group efficiency factor was found which is defined as the ratio pull out capacity of group of anchors to the pull out capacity of single anchor. It was found that the group efficiency factor was found to be greater than 1 and further as S/B ratio increases the group efficiency factor decreases for same H/B ratio. Also as H/B increases the efficiency factor also increases. The anchor breakout factor (Nγ) was also found which tends to increase with increase in depth of embedment and decreases with clear spacing between the anchors. The present data was compared with that of published literature on single anchors and it was found to compare well.
The Behaviour and Performance of Geo-Textiles with Reference to CBR Value on Clay Soil
Authors: Sandhya Rani R. , Hyma A , Ravi Shekar K. , Pradeep Kumar P.
Published: February 2018

Geo-textiles are polymers of high tensile strength, and they are flexible in nature. They are widely used in a variety of engineering applications including soil reinforcement. Hence, it was necessary to make an in depth study on the use of geo-textiles and their relative advantages. This work focuses on a comparative study on the load carrying capacities using geo-textiles. A series of California Bearing Ratio (CBR) tests were performed on soil reinforced with geo-textiles, placed in single and double layers at different depths. The CBR value and stress-strain results of this study provided a better understanding on the comparative changes in load carrying capacities of the soil. The information will help in better decision making in the field of soil reinforcement.
Geotechnical Evaluation of Traditional ‘Bunds’ - Earthen Levees - From Goa
Authors: do Carmo Souza Leonardo Roque , Kandolkar Sumitra S.
Published: February 2018

Ancient Goa was reclaimed from the marshy deltas by remnants of the Saraswat Civilization who settled there and brought with them their ancient technology. We need to learn from these ancient structures that have survived nearly 8000 years and therefore are truly sustainable. Their construction method needs to be replicated to help India’s growing infrastructure demand and lowland reclamation. They use renewable, locally available materials like Soil, Lime, Ash, Cowdung and Straw. They are multi functional: habitation, irrigation, pisiculture, agriculture, rainwater harvesting, infrastructure etc. they possess a stable shape. They save at an average 80% more space than standard embankments. A 6-8% mix of Lime and Coconut Leaf Ash gave best results for soil stabilization. They have good slope stability with a factor of safety of more than 1.5. They have no seepage problems. The self-repairing sustainable coconut tree root system provided 20% more shear strength and seismic stability. As they have already existed for many years they are already undergone settlement and consolidation. This is green engineering that has scope for ancient technology aiding modern technology and spurring India’s growth in it race for international primacy as a technological superpower.
Incorporation of Axial Aging Effects of Pile Foundations into Pushover Analysis of Offshore Jacket Platforms
Authors: George Jerin M. , Kurian V. John , Wahab M.M.A.
Published: February 2018

The integrity assessment of jacket platforms using non-linear pushover analysis in the past had shown that most of the platform failure occur due to the lack of strength in the pile foundation. When the failure of jacket platforms in extreme weather conditions were studied, it was observed that the foundation was intact while the platform failed. This disagreement between the simulation and the actual condition can be explained by the phenomenon of Aging of pile foundations. Experimentally, the axial capacity of pile foundations have been found to be improving with time due to aging. The rate of improvement of the capacity can be empirically predicted using the properties of the soil in which the pile is installed. An empirical equation namely Skov and Denver equation was utilised to determine the improvement in capacity of offshore jacket piles in this study. This improvement was incorporated into the pile-soil modelling of jacket platforms using a new, yet very simple technique of stepping up the axial soil structure interaction curves. Pushover analysis of two offshore jacket platforms with the modified pile-soil model was done using the software SACS. The RSR (Reserve Strength Ratio) obtained from the pushover analysis showed significant difference due to the incorporation of the axial aging effects of the piles. Jacket A has showed a maximum improvement in RSR of 11% and a maximum reduction of RSR of 11% whereas Jacket B has showed a maximum improvement in RSR of 27% and a maximum reduction of RSR of 17%. The study has given a good insight into the changes in behaviour of a jacket platform due to aging of its pile foundations and is expected to improve the structural integrity assessment techniques of aged offshore jacket platforms.
Seismic Response of Multistoried Building with Different Foundations Considering Interaction Effects
Authors: Shetgaonkar Shreya , Savoikar Dr. Purnanand
Published: February 2018

Current seismic design practice assumes the base of the building to be fixed and does not consider the flexibility of foundation and soil. This assumption is realistic only when the structure is founded on solid rock or when the relative stiffness of the foundation soil compared to the superstructure is high. Whereas, in reality due to natural ability of soil to deform, supporting soil medium modifies the response of the structure during earthquake to some extent. In this work the effect of soil structure interaction on seismic response of building resting on different types of foundation was studied. Present work aims to study the effect of soil structure interaction on seismic response of building resting on fixed base, pile foundation, raft foundation and combined pile-raft foundation. G+9 RCC building is analyzed for earthquake loads considered in zone III by response spectrum method and storey displacement and base shear force of building by considering and without considering SSI effect is found out by using MIDAS GEN software.
Geotechnical Characterization of Dredged Material and Effect of Lime Stabilisation on its Strength Characteristics
Authors: Mohammad Sabreena , Akram Wasim , Mirza Shakeel A.
Published: February 2018

Increase in developmental activities and the limited availability of suitable sites for civil engineering project construction is greatly encouraging engineers to consider improvement of weak soil deposits for constructing infrastructures. Among various weak soil deposits, “Dredged Material” from famous Lakes is causing serious health and environmental problems. Dredging of lakes generate lot of waste material, which needs to be disposed-off methodically without disturbing environment. Many Researchers have reported that geotechnical properties of dredged material qualify it for use in the manufacture of high value advantageous products. For all applications, a brief study about Geotechnical characterization of dredged material is very important, which will help in proper use of this material as well as sustainable development of the Dal Lake. Therefore, in this study, an attempt is being made to highlight some geotechnical properties of this solid waste for its bulk utilization in various construction activities. The stabilization of the dredged soil with lime is an effective means of chemical stabilization of soils and it is seen that the index and engineering properties of dredged soil are significantly altered by the addition of lime. A significant step is being taken by this study to achieve economic use of construction materials by attempting to prevent the wastage of such soil material through the improvement of its properties to meet the requirements.
Microtexture Study: Effect of Different Irradiation Sources on Zirconium and its Alloys
Authors: Revelly Ajay Kumar
Published: February 2018

The comparative study of Ga+ ion, Nb+ ion, proton and electron (H+ and e-) irradiation on single crystal and poly crystal Zirconium (Zr), characterised in terms of misorientation profile change, EBSD maps or microtexture, XRD residual stresses development and irradiation hardening effect. It was concluded that the rate of damage is varying with respect to irradiation source. In the present study both the Zr and its alloys were used to conclude this main objective.
Turbulent Natural Convection in Partitioned Square Cavities with Different Lengths and Positions
Authors: Nouri-Borujerdi A. , Sepahi F.
Published: February 2018

The effect of partition on turbulent natural convection has been investigated numerically with different lengths and positions in an air filled square cavity. The top wall of the cavity is assumed to be cold and the other three walls are hot. Two-dimensional governing equations based on Reynolds-averaged Navier-Stokes equations are solved numerically by control volume method in a staggered grid manner. The iterative SIMPLE algorithm is also used to solve the discretized momentum equations to compute the intermediate velocity and pressure fields linked through the momentum equations. The hybrid differencing scheme which is based on a combination of central and upwind schemes is employed to discretize the convective and diffusion terms of the equations respectively. To describe the structure of turbulent flow which is changed due to the increasing importance of viscous effects, wall function was applied to simulate the turbulent flow. The results show that when the partition is placed on the top or bottom wall, the heat transfer rate through the bottom wall increases by increasing the partition length. The number of vortices established in the cavity depends on the partition length. Furthermore, when the partition is mounted on the left or right wall, only a small part of the top wall has a direct interaction with the left wall and the rest of that has an indirect interaction with the bottom wall.
Integrated Thermal Structural Analysis of Advanced Composite Plates and Shells
Authors: Thangaratnam Kari , Divya Divya , Kumar Evangeline
Published: February 2018

Thermo-structural analysis with advanced composite plates and shells has been performed using Finite element method in order to determine temperature response and associated thermal stress. On solving the Fourier’s heat conduction equation, temperature profile is arrived at, with the assumption of linear/uniform temperature distribution through the thickness. Finite element program is developed for steady-state heat transfer problems using Semiloof shell element. Validation for integrated thermo-structural analysis has been done and compared with the available results from literature. The new results thus obtained are presented in terms of temperature, thermal stress, and displacement. The results obtained will be useful particularly in nuclear reactor vessels and Thermal Protection System (TPS) in aeronautical engineering.
Mixed Culture Microalgae-Based Coconut Biodiesel as Fuel to Improve DI CI Engine Performance, Emission Characteristics
Authors: Katam Ganesh Babu , Veeresh Babu A. , Madhu Murthy K. , Kumar M. Kiran
Published: February 2018

The depleting Fossil fuels reserves are caused to look into new Renewable energy sources to fulfill Diesel fuel demand in developing countries such as India. Increasing urbanization is lead to the search for new alternative sources like biodiesel. In India demand of diesel fuel in Industry and Transportation sector. To resolve all the above problems, researchers, scientists were produced biodiesel from first, second and third generation biodiesel sources. Among all the sources Algae was the most Oil rich sources. The byproducts in algae to biodiesel conversion process are most valuable than other. In the present work author tried to work in a new approach, i.e. the mixed culture algae particles are emulsified in pure Coconut biodiesel fuel by using TritonX-100 as a surfactant to prepare an emulsified fuel. This fuel sample was applied to DI CI engine to improve performance, emission characteristics. The experimental results were shown that there is the improvement in diesel engine performance; emission characteristics especially break thermal efficiency and NOx emission reduction than diesel fuel due to its clean combustion.
Levelized Cost of Electricity and Plant Load Factor of 7.5 MW Grid Connected Biomass Power Plant
Authors: Sharma Rashmi , Saxena Bharat Kumar , Rao K.V.S.
Published: February 2018

Large amount of agricultural waste is produced after harvesting of crops like wheat, paddy, soya-bean, maize, mustard, sugarcane, groundnut etc. The conventional way is to burn it in the fields or dump it across the wasteland. The burning of biomass residue in the fields has very adverse effect for the environment and leads to air pollution. A more efficient way is to use biomass residues of agricultural crops for production of electricity through biomass based power plants. In India, grid connected biomass power and co-generation installed capacity has increased from 1,102 MW in 2006 to 8,182 MW in 2017. This paper analyses the twenty years’ performance of a 7.5 MW biomass power plant situated at Rangpur village near Kota city of Rajasthan, India, based on capital cost, present cost of biomass per tonne, data obtained from 2006 to 2015 related to annual power generation, and annual consumption of biomass. Levelized Cost of Electricity is found to be varying from Rs. 4.43/kWh to Rs. 4.64/kWh for interest rates varying from 8% to 16%. Plant Load Factor is found to be varying from 29% to 82% during the period of 2006-07 to 2014-15 for nine years, with an average plant load factor of 73%.
Lattice Boltzmann Simulation of Transient Natural Convection in a Staggered Cavity with Four Vertically Heated Walls
Authors: Gogoi Bidyut B.
Published: February 2018

The work in this manuscript deals with the numerical simulation of natural convection in a staggered cavity with the help of a recently developed two-dimensional double Multiple-Relaxation-Time (MRT) thermal Lattice Boltzmann method (LBM). In the last decade, there has been a rapid rise in the development of Lattice Boltzmann methods. However, its application in the simulation of natural convection from a staggered cavity has been carried out for the first time in this study. A careful undermining into the existing literature of heat and mass transfer reveal that study of natural convections in cross-sectional cavities is notably absent. Therefore, in this manuscript, we attempt to review the recently developed method and tried to analyze its implementation on natural convection in a staggered cavity with four differentially heated vertical walls. The problem geometry has eight boundaries. It is a staggered cavity with adiabatic horizontal walls and differentially heated vertical walls. The flow inside the thermally driven staggered cavity has been carefully studied for Rayleigh numbers 103, 104 and 105. The velocity and pressure boundary conditions are determined by a non-equilibrium extrapolation rule. As no benchmark results are available in the literature for this relatively new problem, we carry out its simulation with the help of a yet another well established scheme. This scheme is a higher-order compact (HOC) scheme with fourth order spatial accuracy and second order temporal accuracy. Our results show that there is a very good agreement between both these methods which exemplifies the accuracy and credibility of our results.
Characterization of Exponential Cohesive Zone Model for Fracture Assessment of De-Bonded Composite Panels
Authors: Muthupandian J. , Pradeep Koovaparambil Ramunny
Published: February 2018

Composite structures are prone to delamination/de-bond and effective tool to simulate de-lamination is cohesive zone model. Cohesive zone model uses multiple adhesive failure parameters. The influence of adhesive parameters on the delamination and fracture of Double cantilever Beam, subjected to Mode-I loading through finite element simulations is studied usingExponential Cohesive Zone Model (ECZM). Influence of Normal stress (σ), normal deflection (δn) and tangential deflection (δt) on the de-bond propagation is examined.From the analysis it is found that the tangential deflection (δt) has negligible impact on Mode-I loading and fracture of the specimen. Significant effects are seen for the perturbation of Normal stress (σ) and Normal deflection (δn). A Finite element based ECZM for composite layer (HTS/M18) with EPG 2601 adhesive is proposed. The model is validated by comparing with test data.
Study on Mechanical Property of Aluminium 6061 with E Glass Fiber Reinforced Composite
Authors: Vinayashree Vinayashree , Shobha R.
Published: February 2018

Aluminium composites are in predominant use due to their lower weight and high strength among the MMC’s. Aluminium 6061 is selected as matrix and E-glass fiber is selected as reinforcement. Fabrication of composite is done by stir casting method. Each fabrication carries the E-glass reinforcement content varied from 2% to 10%. The present article attempts to evaluate the mechanical properties of E-glass fibre reinforced composite and study the effect of reinforcement on the matrix alloy through mechanical properties. When compared to ascast mechanical properties the UTS has increased from 74.28 N/sq mm to 146.8 N/sq mm for a composite at 6% E-glass. The hardness of as-cast has also increased from 22 RHB to 43 RHB at 6% E-glass and the wear of composite has exhibited a decreasing tend with increase in reinforcement content along the sliding distance. The results are analyzed in certain depth in the current paper. The mechanical properties of composites have improved with the increase in the weigh percentage of glass fiber in the aluminium matrix.