bluuebunny/crossref_metadata_2025 huggingface dataset:
Observations on global urban millennials’ social and civic interactions mediated by new technologies
Authors: Abramek Blanca , Casalegno Federico , Dumpawar Suruchi , Gupta Anika , Zeamer Vicky
Published: December 2016

Chercheurs et visionneurs de la ville ont centré beaucoup d’attention sur la smart city du futur. Dans cet article, nous proposons une méthodologie de recherche qualitative qui place la proposition de la ville du futur dans les expériences et attentes actuelles du groupe de population qui grandit le plus dans ces villes : Millennials, cette population comprise entre les 18 et 35 ans. Sur la base de nos résultats, nous décrivons des tendances clés dans le comportement urbain des Millennials et les lions aux développements dans les infrastructures et connexités urbaines. Enfin, nous utilisons ces tendances comme base pour la proposition d’une Networked City , une ville caractérisée par l’information ouverte liant l’infrastructure numérique et physique et se focalisant sur la socialité et l’interaction.
Thermal Conductivity of Human Bone in Cryoprobe Freezing as Related to Density
Authors: Walker Kyle E. , Baldini Todd , Lindeque Bennie G.
Published: December 2016

Cryoprobes create localized cell destruction through freezing. Bone is resistant to temperature flow but is susceptible to freezing necrosis at warmer temperatures than tumor cells. Few studies have determined the thermal conductivity of human bone. No studies have examined conductivity as related to density. The study goal was to examine thermal conductivity in human bone while comparing differences between cancellous and cortical bone. An additional goal was to establish a relationship between bone density and thermal conductivity. Six knee joints from 5 cadavers were obtained. The epiphyseal region was sliced in half coronally prior to inserting an argon-circulating cryoprobe directed away from the joint line. Thermistor thermometers were placed perpendicularly at measured increments, and the freezing cycle was recorded until steady-state conditions were achieved. For 2 cortical samples, the probe was placed intramedullary in metaphyseal samples and measurements were performed radially from the central axis of each sample. Conductivity was calculated using Fournier's Law and then plotted against measured density of each sample. Across samples, density of cancellous bone ranged from 0.86 to 1.38 g/mL and average thermal conductivity ranged between 0.404 and 0.55 W/mK. Comparatively, cortical bone had a density of 1.70 to 1.86 g/mL and thermal conductivity of 0.0742 to 0.109 W/mK. A strong 2-degree polynomial correlation was seen (
R
2
=0.8226,
P
<.001). Bone is highly resistant to temperature flow. This resistance varies and inversely correlates strongly with density. This information is clinically relevant to maximize tumor ablation while minimizing morbidity through unnecessary bone loss and damage to surrounding structures. [
Orthopedics.
2017; 40(2):90–94.]
Myeloid Sarcoma in the Orbit
Authors: Qian Xiaoxiao , Gigantelli James W. , Abromowitch Minnie , Morgan Linda A. , Suh Donny W.
Published: December 2016

The authors describe a case of myeloid sarcoma of the orbit in a pediatric patient. An 8-month-old male infant presented to the ophthalmology clinic with a left orbital mass, which had been increasing in size over the previous 2 months. The mass was initially diagnosed at another clinic as an infantile hemangioma, and had been treated with a topical formulation of timolol. In the ophthalmology clinic, orbital magnetic resonance imaging showed a solid enhancing mass. A biopsy was performed, and histopathology revealed myeloid sarcoma. The disease responded well to a standard chemotherapy regimen. Myeloid sarcoma is a rare, extra-medullary presentation that can occur as an isolated tumor, concurrently with or at relapse of acute myeloid leukemia. Because few cases of myeloid sarcoma in the orbit have been reported, this case report aids in the management of myeloid sarcoma in pediatric patients. The report describes an 8-month-old male infant, the youngest patient to develop myeloid sarcoma without preexisting acute myeloid leukemia.

[
J Pediatr Ophthalmol Strabismus
. 2016;53:e64–e68.]
Noster predecessor David: la regalità davidica in Occidente tra XII e XIII secolo
Authors: D’Angelo Francesco
Published: December 2016

[it] L’articolo è dedicato alla figura di Davide, re d’Israele, e al modo in cui, tramite il ricorso al simbolismo tipologico, egli fu evocato come modello e prefi gurazione di alcuni sovrani cristiani tra XII e XIII secolo: Sverrir Sigur›arson raffi gurò se stesso come il “Davide della Norvegia”; Luigi IX fu accostato a Davide per le sue virtù cristiane; per Giovanni Senzaterra il paragone doveva ricordare al re l’elettività della monarchia inglese; infi ne da Gerusalemme Federico II, imperatore universale e unto del Signore, si presentò al mondo come legittimo erede e successore di Davide.
Los músicos en la festividad del Corpus de Sevilla. Entre la baja Edad Media y el Renacimiento
Authors: Bejarano Pellicer Clara
Published: December 2016

Este artículo aborda las primeras referencias históricas a los músicos en la ciudad de Sevilla, que se encuadran cronológicamente desde la Baja Edad Media hasta aproximadamente 1525. El objetivo de este estudio consiste en perfilar los orígenes y antecedentes institucionales de las estructuras típicas de la Modernidad en lo que a aspectos musicales se refiere, para comprobar en qué medida las tendencias apuntadas se consolidaron o se transformaron en el período posterior, ya bien entrado el siglo XVI. La festividad del Corpus constituye un entorno privilegiado de observación. Para ello, se recurre a fuentes archivísticas, narrativas y bibliográficas combinadas.
Indicios de participación ḏimmí o muladí en los asedios carolingios a Tortosa (804/806-809)
Authors: Suñé Arce Josep
Published: December 2016

El siguiente artículo analiza los conceptos utilizados en la Vita Hludowici imperatoris del Astrónomo para designar a los combatientes andalusíes que defendieron Tortosa de los ataques carolingios entre los años 804/806 y 809. De todos esos términos, el de Mauri y el de cives destacan por encima de los demás y, en consecuencia, reciben un trato especial. Tras compararlos con los datos ofrecidos por otras fuentes latinas, musulmanas y arqueológicas, el estudio concluye que con el primero de esos conceptos se hace referencia a grupos de marineros andalusíes, los conocidos en las obras árabes como baḥriyyūn, y con el segundo a las elites hispano-godas de la ciudad de Tortosa.
L’artisanat des matières dures animales : nouvelles connaissances à partir des rebuts d’atelier
Authors: Khan Bénédicte
Published: December 2016

Nombreux et variés sont les objets en os, en ivoire, en corne ou encore en bois de cervidé qui furent fabriqués et utilisés en Méditerranée orientale à l’époque romano-byzantine. Néanmoins, l’artisanat de ces matières est encore mal connu. La pauvreté des sources historiques notamment nous enjoint ainsi à fonder nos ana­lyses presque exclusivement sur l’étude des objets archéologiques, avec un intérêt particulier accordé aux éléments provenant de dépôts secondaires artisanaux. Ces dépôts contiennent en effet une source non négligeable d’informations en lien avec les manières de travailler la matière, principalement à travers la diversité des pièces mises au jour, représentatives de différentes étapes de la chaîne opératoire de production. C’est pourquoi il est nécessaire d’étudier ces dépôts sous le triple spectre de l’archéozoologie, de la technologie et de l’expérimentation, leur complémentarité offrant une compréhension plus globale de cet artisanat et facilitant son replacement dans le cadre général de la société romano-byzantine.
Le cas de la céramique du Bronze récent de la Grèce du Nord et de l’Albanie du Sud
Authors: Krapf Tobias
Published: December 2016

Cet article aborde la question de l’influence de la culture mycénienne sur la région septentrionale de l’Égée sur la base des importations de céramique. Bien que de la céramique ait été importée de la Grèce méridionale/centrale aux côtes de la Macédoine depuis le Bronze moyen, ce n’est qu’à partir de l’HR IIIA2 qu’elle apparaît en plus grande quantité. Ces vases, d’une technique avancée, ont vite été imités en Macédoine centrale dans une chaîne opératoire différente qui n’influença guère la céramique traditionnelle locale. Plus au nord-ouest, sur les sites de Sovjan et Maliq, situés dans le bassin de Korçë, on trouve très rarement des importations mycéniennes dans l’habitat, mais elles jouaient un certain rôle dans les offrandes funéraires prestigieuses. En général, les cultures du nord de l’Égée étaient plutôt conservatrices et les contacts n’avaient pas d’influences substantielles.
L’impact des religions chrétienne et musulmane sur le paysage urbain de Syrie-Palestine (ive-viiie siècle) : Le cas des églises et des mosquées
Authors: Brailly Aurore
Published: December 2016

Après une brève présentation du contexte, nous mettrons en évidence les adaptations de l’architecture urbaine concernant l’organisation des nouveaux espaces liturgiques des villes de Syrie-Palestine, de la christianisation (période proto-byzantine) à l’islamisation (période omeyyade). Nous relèverons ainsi les répercussions sur le paysage urbain de la lutte du christianisme contre le paganisme préexistant pour, ensuite, proposer une évolution du processus de christianisation, du ive au viie siècle, avec le cas des églises. Enfin, nous mettrons en perspective les termes de l’implantation – et non de la lutte – de l’islam face au christianisme, du viie au viiie siècle, avec le cas des mosquées. Ces phénomènes seront observés à Damas avec l’étude du temple de Jupiter Damascène devenu une église dédiée à Saint-Jean-Baptiste puis une mosquée omeyyade.
L’armement, marqueur du pouvoir dans les pratiques funéraires des élites barbares de l’armée romaine tardive et protobyzantine (ive-vie siècle)
Authors: Glad Damien
Published: December 2016

Many publications attribute the fall of the late Roman Empire to the « barbarization » of the army. This paper questions this schematic and restrictive point of view with the balkanic archaeological data, in an area less studied than some others. Starting from markers of power, Empire’s influence on the barbarian chiefs with prestigious weapons allow to confirm their integration within the elite of the Empire. From one burial excavated in Durostorum necropolis, this paper analyzes late roman and early byzantine prestigious weapons as markers of power.
De Chauvet à Lascaux
Authors: Petrognani Stéphane
Published: December 2016

Obviously “Ancient” rock art has been less studied than Magdalenian art; the reason for such a lack of interest may be its less spectacular character and its apparent relative rarity. Studies carried out by Jean Combier in the Ardeche valley since the late fifties, by Michel Corblanchet in the Lot as early as the seventies as well as those by Brigitte and Gilles Delluc in Aquitaine contributed to correct this imbalance. The study of “archaïc” rock art in Aquitaine by the Delluc constitute the only real synthesis about “ancient” parietal art. Nevertheless, this study is limited to Aquitaine. Broadening this geographic domain to the whole France and taking into account recent findings (Cosquer, Chauvet, Cussac) gives a new drive to research. We define as “ancient” the ornate aurignacian, gravettian and solutrean (pre-magdalenian) ensembles. In our study we concern ourselves with putting into perspective recently found elements and elements to be reconsidered within the chronology. Can we differentiate aurignacian, gravettian and solutrean cultures through a thematic and technostylistic approach? Does this double approach allows to isolate “momentary traditions” and “symbolic territories” within aurignacian, gravettian and solutrean complexes?
« Pierres », « Idoles », « Statues » : les stèles mayas vues par les Espagnols à la conquête du nouveau monde
Authors: Ferran Elise
Published: December 2016

Dans ce travail nous souhaitons aborder la difficulté d’interprétation d’un objet iconique dont le contexte socio-culturel a été en grande partie perdu. Plutôt que de focaliser notre attention sur les images produites, nous mettrons l’accent sur la pluralité des regards portés sur ces images. Au xvie siècle, les missionnaires espagnols découvrent des objets mayas qui leur sont complètement étrangers, mais qu’ils décrivent suivant leurs propres référents culturels. Quoique fortement ethnocentriques, ces témoignages restent des sources documentaires inestimables pour la compréhension de l’art maya. « Pierres », « idoles », « statues », sont des termes qu’ils ont tour à tour employés pour décrire ce que les archéologues nomment aujourd’hui « stèles mayas », tantôt figuratives, tantôt aniconiques. Nous illustrerons comment le regard posé sur les Mayas et leurs objets de culte, au moment de la Conquête, contribue à construire notre propre regard de l’art et de la société maya.
Les fondations culturelles arabes et les métamorphoses du panarabisme
Authors: Mermier Franck
Published: December 2016

Cet article traite des transformations du panarabisme à travers l’étude de plusieurs fondations culturelles panarabes en montrant comment l’érosion de sa dimension politique nationaliste s’est faite au profit d’un panarabisme culturel relayant souvent la volonté d’hégémonie des Etats, notamment ceux du Conseil de coopération du Golfe. Il montre que le panarabisme, en dépit de sa dissociation d’avec le nationalisme arabe, conserve cependant une fonction de légitimation politique, ce qui se traduit par une montée des rivalités et une surenchère d’investissements dans les domaines de la culture, de l’éducation et de la science, moins peut-être au niveau des politiques publiques que dans celui de la diplomatie culturelle. L’étude questionne aussi l’émergence, au niveau régional, d’organisations non gouvernementales visant à promouvoir de nouvelles formes d’expression artistique et véhiculant de nouvelles conceptions du panarabisme culturel.
Égyptiens expatriés aux Émirats arabes unis : ancrages, connexions transnationales et expériences cosmopolites
Authors: Pagès‑El Karoui Delphine
Published: December 2016

Dubaï se révèle particulièrement attractive pour les Égyptiens, leur offrant un mode de vie occidental, moderne et globalisé, dans un pays arabe et musulman. En dépit d’un intérêt croissant pour le Golfe, peu de travaux récents ont étudié les migrants arabes. Quels ancrages les Égyptiens développent-ils aux Émirats, malgré la précarité de leur statut ? Leurs connexions transnationales sont-elles d’autant plus fortes que l’intégration à la nation leur est refusée ? Quelles expériences font-ils de la super-diversité dans ces villes cosmopolites ? Après avoir interrogé l’existence d’une communauté égyptienne, nous montrerons comment certains Égyptiens, après de longs séjours, peuvent développer des sentiments d’appartenance à la ville (mais pas au pays, ni à la région du Golfe), et comment s’élabore une égyptianité transnationale, surtout chez les secondes générations. On s’intéressera aussi à l’intensification des pratiques transnationales depuis 2011, comme une réponse à l’accroissement de l’insécurité migratoire.
Les non-dits de l’asile en Afrique subsaharienne
Authors: Lassailly-Jacob Véronique
Published: December 2016

Au sortir de 13 années de lutte armée pour la libération nationale qui s’acheva par l’indépendance en 1975, le Mozambique connut ensuite, dans le contexte de la guerre froide, une longue guerre civile de 1976 à 1992 qui entraîna à nouveau la fuite de milliers de réfugiés dans les pays limitrophes. En Zambie, ils furent regroupés, assistés et protégés par le Haut commissariat aux Réfugiés de l’ONU (HCR) et de nombreuses Organisations Non Gouvernementales (ONG) dans un vaste site agricole avant d’être rapatriés en 1993 et 1994. Cet article analyse la méthodologie et les résultats d’une enquête à passages répétés menée par l’auteur entre 1993 et 2007 dans ce site de réfugiés. Il révèle d’une part les difficultés de l’enquête sur le temps long et sur les situations d’urgence et d’illégalité et d’autre part, les non-dits d’une politique d’asile qui utilise la présence des réfugiés pour mettre en valeur le territoire par leur force de travail et par les investissements de la communauté internationale. Ce sont des éléments de compréhension sur la faisabilité et les enseignements de l’enquête à passages répétés dans un site de réfugiés qui sont ici discutés.
Generation of Atmospheric Constants over Some Locations in West Africa: A Theoretical Aid for Measuring Instruments Design
Authors: Emetere Moses E. , Akinyemi Marvel L.
Published: December 2016

The performance of AERONET or AMMA in West Africa over the past two decades had been successful but not without its challenges. These challenges had resulted in the loss of large volume of useful data. The frequent failures of ground measuring devices over West Africa have been linked to the manufacturer and christened 'manufacturer-error'. In this paper, it was proposed that the frequent failure of ground measuring devices is due to systemic-error. To address the systemic-error, we propose that the configuration of the constants-embedded in the compact flash of the measuring devices is not compatible with the atmospheric conditions of the West African climate. A statistical investigation was carried out on both the ground and satellite dataset to determine the aerosols retention capacity within the West African space. A dispersion model was developed to incorporate salient assumptions and parameters like the Unified number. Fourteen and thirteen years dataset were obtained from Multi-angle Imaging SpectroRadiometer (MISR) and AERONET respectively. Five locations were considered in this study; Ilorin-Nigeria, Ouagadougou-Burkina Faso, Lome-Togo, Conakry-Guinea and Niamey-Niger which are positioned on latitude 8.5 oN, 12.37 oN, 6.17 oN, 9.55 oN, 13.5 oN and longitude 4.53 oE, 1.53 oW, 1.35 oE, 13.67 oW, 2.12 oE respectively. It was observed that the same aerosols retention occurred in West Africa region between 2003 and 2005. Also, it was observed that the high aerosols retention over the locations portray danger to the life form, such as unbearable thermal comfort, increased heat flux, partial famine e.t.c. Hence, the proper documentation and execution of the correct atmospheric constants over locations of West Africa is a novel concept.
Factors that Influence Students' Decision to Choose a Particular University: A Conjoint Analysis
Authors: Ghansah Benjamin , Benuwa Ben Bright , Ansah Ernest Kwame , Ghansah Nathaniel Ekow , Magama Cwebile , Ocquaye Elias Nii Noye
Published: December 2016

Ghanaian universities have employed various marketing mix to stimulate demand for their services; particularly in recruitment and engagement of home and international students. This paper examines the relative influence of factors affecting the college choice decisions of students. It is based on a survey of 2,534 admitted students at a major university in Ghana, to which 39 percent of the sample responded. We used Factor analysis to rate 26 University borne attributes upon which student decisions are based. The outcome was used to build a five-scale preference measure, which were evaluated with a qualitative approach in analyzing gathered data using descriptive statistics, cross tabulation and chi square. The results revealed some marketing strategies that can be used in institutions of higher learning to boost students’ enrolment in their order of perceived effectiveness. The following were found to influence decisions: word of mouth (family and friends), proximity/nearness, accreditation/affiliation, affordability and lecturing Style.
Overall Performance Improvement of an Small Scale Venture Using Critical Key Performance Indicators
Authors: Nallusamy S.
Published: December 2016

Inventory theory and supply chain management have become important to small businesses in order to improve an organization’s competitive strength and survival. The rapid growth of small businesses of late has seen them to face a challenge in managing their inventory effectively and efficiently. A study was carried out in F.E. (Private) limited a pioneer in distribution of electrical equipments based in Chennai, whose two major challenges were, stock-out and excess stock due to uncertainty in demand. The organization wanted to develop its performance and overall efficiency by considering a change in the inventory policy. The main aim of this research is to attain operational excellence through inventory management and measure its effectiveness using critical key performance indicators. A new inventory policy was developed to improve the inventory turns and measure its performance after implementing the new inventory policy. The results revealed that the implementation of new inventory policy helped to save over Rs. 2.25 lakhs per month in terms of total inventory carrying cost to the selected organization.
Specific System Random Load Forecasts for Nigerian 330 kV 38-Bus Transmission Grid
Authors: Melodi Adegoke Oladipo , Adeyanju Olatunji M.
Published: December 2016

This study presents random load forecasts for the Nigerian 330 kV 38-bus transmission grid using a complex trend analysis technique. By considering randomness of monthly load peaks and normal distribution function, yearly load mean and confidence intervals were predicted for the transmission buses from an obtained 10-year historical load population. Also using the proposed algorithm of the mentioned technique, long-term random load forecasts for the transmission system were obtained. The obtained forecasts were compared with results from an earlier prediction model created for the same grid, which comprises a Monte Carlo technique that considers the location’s predominant control variables as population and GDP growth; the maximum obtainable error was 24%. The obtained results of forecasts and comparison are applicable for determining effective transmission system planning policy in Nigeria for the forecast period.
Chloride Resistance of Recycled Aggregate Concrete under Wetting-Drying Cycles
Authors: Qi Bing , Gao Jian Ming , Shen Da Man
Published: December 2016

Recycled aggregates concrete (RAC) becomes an important participant in recycled materials. This study was performed in order to evaluate the effect of recycled coarse aggregates (RCA) on the chloride resistance of concretes with different coarse aggregates replacement ratio under wetting–drying cycles. Composition influence on the concrete were studied with different the addition of admixtures. The results indicate that the free chloride content decreased with the increasing of depth, whist it increased with the increasing replacement ratio of RCA at the same depth. Wetting–drying cycles accelerated the process of chloride diffusion. It was also found that the addition of admixtures can improve the ability of chloride resistance of concrete.
Sea Water Effects on Surface Morphology and Interfacial Bonding of Sugar Palm Fiber to Sago Matrix
Authors: Mardin H. , Wardana I.N.G. , Kusno Kamil , Pratikto  , Wahyono S.
Published: December 2016

Effects of sea water immersion for palm fiber in relation to surface morphology, roughness and bonding between the fiber and sago matrix were observed. Duration of immersion varied in 1, 2, 3 and 4 weeks, and then dried at room temperature for 3 hours continued by oven at 80 °C for 6 hours. SEM and roughness arithmetic tests were applied to see surface morphology, roughness and bonding between fiber and the matrix. Result shows fiber morphology and roughness varies by the duration of immersion. The surface roughness increases as immersion continues along with fiber - matrix bonding improvement. The maximum duration of 4 weeks fiber immersion resulted in the best interlocking of matrix and fibers, as the slits between them disappear.
Phase Field Simulation of Grain Growth with Particle Pinning
Authors: Teng Chun Yu , Fu Yun , Ren Zhan Yong , Li Yong Hong , Wang Yun , Ouyang Wen Li
Published: December 2016

The properties of alloys depend on its microstructure, such as the size of grains. In general, the balanced mechanical properties of alloys can be obtained with small grain size. While the grain size of alloys may increases under heat treatment, thermal mechanical processing and service condition of high temperature, i.e., the grain growth is inevitable. The effort of most research is to control the rate of grain growth and avoid abnormal grain growth. For example, pinning the grain boundary and reduce its mobility with the second phase particles in order to prevent grain growth. Therefore, the properties of the alloys will not decreases dramatically and the structure retains a high degree of integrity. The details of grain growth with particle pinning were investigated by phase field simulations in the present paper. It is found that, with the same size of pinning particles, the pinning effect increases with the increases of the pinning particle number. With the same pinning particle number, the pinning effect increases with the increases of pinning particle size. Under the same total volume of pinning particles while different particle size and number, the pinning effect is complicated and it will be discussed in details. The pinning effect decreases with the increases of grain boundary energy. These findings could shed light on the understanding of the grain growth kinetics with particle pinning.
Rate-Dependent Material Parameters of the Combined Isotropic/Kinematic Hardening Model for the TRIP980 Steel Sheet
Authors: Joo Geun Su , Huh Hoon
Published: December 2016

This paper is concerned with rate-dependent hardening behaviors of the TRIP980 steel sheet. In sheet metal forming, sheet metals experiences complicated loading at various strain rates. In order to predict deformed shape in sheet metal forming, accurate material properties and an appropriate constitutive model in numerical simulation are important to consider reverse loading and various strain rates simultaneously.This paper deals with rate-dependent material parameters of the isotropic/kinematic hardening model. Tension/compression tests of the TRIP980 steel sheet are performed with a newly developed experimental technique at various strain rates ranging from 0.001 to 100 s−1. Tension/compression hardening curves of the TRIP980 steel sheet are approximated by the Chun et al model at each strain rate condition respectively. From acquired material parameters, rate dependencies of tension/compression hardening behaviors are investigated.
Measurement of Bauschinger Effect in Ultrafine-Grained A1070 Aluminum Rods
Authors: Koizumi Takayuki , Kuroda Mitsutoshi
Published: December 2016

In this study, the Bauschinger effect in ultrafine-grained pure aluminum rods (A1070) was investigated. The samples were produced by multipass equal-channel angular pressing (ECAP) with ‘route BC’, which is known to give nearly equiaxial-shaped crystal grains. Dumbbell-shaped specimens with a circular cross section were machined from the samples subjected to ECAP to carry out uniaxial tensile and compressive tests, which were followed by reversal of the loading direction at a prestrain of 1%. The influence of the grain size on the intensity of the Bauschinger effect was investigated. The Bauschinger effect is interpreted to be a manifestation of internal stresses produced near the grain boundaries by the accumulation of dislocations. On the basic of our experimental results, the roles of the grain boundaries, which are usually at least partially considered as barriers to dislocation motion, are reconsidered.
On the Role of Grains in Plastic Deformation and Low Cycle Fatigue of Polycrystalline Metal
Authors: Abe Takeji
Published: December 2016

In the previous papers, the author discussed the role of r-value (anisotropic parameter in plasticity) on the surface roughening after plastic deformation. In the present paper, discussion is made on the effects of mutual constraint of deformation between neighboring grains at the grain boundary on the surface roughening. A characteristic parameter called constraint ratio is introduced to express the degree of the mutual restriction between grains. The well-known Coffin-Manson relation in low cycle fatigue is deduced considering to the surface roughening after cyclic deformation.
MD Analysis of Effect of Relative Humidity on Molecular Chain’s Network Structure of PEM
Authors: Riku Isamu , Kawanishi Keisuke , Mimura Koji
Published: December 2016

To clarify the effect of relative humidity on molecular chain’s network structure, we at first employ Molecular Dynamics (MD) method to constitute the computational model for Nafion membrane, in which the water channel is artificially reproduced with an aggregation of water molecules. And then, relaxation calculation is performed and a relatively stable microstructure of Nafion membrane is derived. It is found that the regions of relatively low density of molecular chain’s network appear interchangeably together with those of relatively high density of water molecules.
Experimental Study and Finite Element Simulation of Bending Fretting Fatigue for Tempered 42CrMo Steel
Authors: Ding Jun , Zhu Yi Lin
Published: December 2016

In this paper, experiments of the plain bending fatigue for cyclic softening material tempered 42CrMo steel plate and the bending fretting fatigue for tempered 42CrMo steel plate against 52100 bearing steel cylinder are conducted. The difference of the bending fretting fatigue and the plain bending fatigue for tempered 42CrMo steel is analyzed, and the effect of cyclic bending loads with the same normal load on the fatigue lives is discussed. Besides, finite element simulations of the bending fretting fatigue process for tempered 42CrMo steel by ABAQUS are carried out. In this simulation, an advanced cyclic elasto-plastic constitutive model is implemented in to ABAQUS as a user material subroutine (UMAT) in order to consider the influence of ratchetting and cyclic softening feature. And a simplified equivalent two-dimensional plane strain finite element model with an equivalent normal force obtained from the three-dimensional finite element model is adopted. From the numerical simulation, the influence of cyclic bending loads on the bending fretting fatigue for tempered 42CrMo steel is discussed, and then the bending fretting fatigue lives are estimated by employing Smith–Watson–Topper critical plane criteria. Comparison with the corresponding experiments shows that the estimated results are in good agreement with the experimental results.
Atomistic-Level Simulation of Deformation in Polycarbonate
Authors: Kubo Atsushi , Umeno Yoshitaka
Published: December 2016

Coarse-graining molecular dynamics simulations were carried out for deformation and fracture problems in polycarbonate. The effects of temperature and molar mass on deformation behavior were qualitatively investigated. Temperatures below the glass transition point were examined. The temperature effect was found to be consistent with all-atom simulations and experiments. On the investigation of molar mass effect, it was revealed that complex entanglement of massive molecules can prevent voids from growing.
Effects of Non-Associated Flow Rule on AHSS Shear Fracture
Authors: Lee Hong Woo , Oh Kyung Seok
Published: December 2016

Recently, advanced high strength steels (AHSSs) have been widely applied to the structural parts of vehicles thanks to their good combination of strength and ductility. When one makes parts with AHSSs, however, fractures in sharp corners of the parts are frequently observed below forming limit, which is normally defined by strain based FLC(Forming Limit Curve). This phenomenon is well-known as “Shear Fracture”. Recent researches point out that additional numerical techniques should be considered in order to predict it accurately. Kim et al. [1] suggested that shear fracture can be predictable with continuum-based finite elements rather than conventional shell elements, and more constitutive informations for large strain thermo-mechanical simulation are needed to improve accuracy. Luo and Wierzbicki [2] showed that shear fracutre in stretch-bending test can be fully characterized by proposed MMC(Modified Mohr-Coulomb). This paper shows that solid-shell approach based on hyper-elastoplastic material model enables one to properly predict shear fracture pheonomenon without any special failure criteria. Furthermore, the effects of non-associated flow rule on shear fracture will be also discussed with several numerical examples.
Influence of Geometrical Imperfection on Failure Mode of DP780 Steel Utilizing Damage Models Embedded RVE Technique
Authors: Zhao Kun , Zhuang Xin Cun , Pei Xin Hua , Zhao Zhen
Published: December 2016

As dual-phase (DP) steel sheet is widely used in automotive manufacture, researches on failure mode of DP steel have been carried out experimentally and numerically in recent years. In this paper, failure mode of DP 780 steels with geometrical imperfection, which was assumed as a consequence of previous process, was investigated via a microstructure approach utilizing RVE technique. Multiple damage models were applied on characteristic microstructures and the modified pointed-ended geometrical imperfection was ingrained. Considering the progress of crack evolution, the depth and the location of geometrical imperfection were critical factors in determining the mode of crack initiation and propagation. Essentially, geometrical imperfection influenced the failure mode of investigated DP steel via aggravating the structural heterogeneity.
Anisotropic Damage Evolution for Perforated Sheet under Tensile Deformation
Authors: Nagaki Shigeru , Saboi Daigo , Muroi Kenta , Iizuka Makoto , Oshita Kenichi
Published: December 2016

It is important to formulate a constitutive equation which represents the growth of voids during plastic deformation in order to predict ductile fracture of metallic materials. For this purpose, we proposed an anisotropic Gurson’s yield function with the damage tensor, which represents the anisotropy due to the void distribution and the damage evolution was assumed isotropic for simplicity. Then we also proposed an anisotropic void growth law derived from the anisotropic Gurson’s yield function based on thermodynamic consideration. In this study we carried out the uniaxial tensile test of perforated sheets of stainless steel and aluminum alloy as the ideal two dimensional model of the damaged material and investigate the damage growth during plastic deformation. As a result, we obtained a good agreement between the experimental and the calculated void growth for both materials and it is also found that material parameters for damage evolutions are almost the same for both materials and are hardly affected by the work-hardening exponent.
Effect of Lattice Rotation on Hardening Behavior of HCP Metals
Authors: Kurisu Takaaki , Tadano Yuichi , Hagihara Seiya
Published: December 2016

Strain hardening behavior is known to strongly affect the formability of metallic sheets. The effect of lattice rotation on the hardening behavior of hexagonal close-packed (HCP) metals is numerically investigated using a homogenization-based crystal plasticity model to represent the polycrystalline behavior. The effect of lattice rotation on strain hardening behavior evaluated using different initial textures, and the geometrical hardening effect of HCP metals is investigated. In addition, the critical resolved shear stress of each slip system is varied and is shown to affects the strain hardening in HCP metals. In this study, we further discuss the possibility to improve the formability of HCP metals.
Transient Thermal Analysis of Cold Strip Rolling Considering Rough Surface Contacts
Authors: Wu Chu Han , Qu Pei Lei , Zhang Liang Chi , Li Shan Qing , Jiang Zheng Lian
Published: December 2016

This paper presents a transient thermal analysis of cold strip rolling, integrating both the microscale asperity deformation and macroscale strip deformation. A statistical characterisation was carried out to obtain the contact pressure and thermal contact conductance at the roll-strip interface. To address the effects of rolling speed and temperature rise, Johnson-cook constitutive model of yielding strength was employed to incorporate the strain rate and temperature variation in the analysis. It was found that the developed model can successfully predict both the interface contact stress and temperature rise in the rolling bite.
Investigation on Wrinkling Deformation in Multi-Pass Incremental Sheet Forming Process
Authors: Liu Zhao Bing , Meehan Paul Anthony
Published: December 2016

Incremental Sheet Forming (ISF) is a promising rapid prototyping technology used to form complex three-dimensional shapes. For forming a part with severely sloped regions, design of multi-stage deformation passes (intermediate shapes or preforms) before the final part, is widely adopted as a desirable and practical way to control the material flow in order to obtain a more uniform thickness distribution and avoid forming failure. However, a problem sometimes encountered in multi-pass forming is wrinkling deformation between two adjacent deformation passes. This may lead to forming process instability and even fracture. The overall quality of the final part may also deteriorate even if the part is formed successfully. In this paper, the wrinkling phenomenon in multi-pass incremental sheet forming is investigated by means of finite element analysis (FEA) and experimental tests to analyse the wrinkling formation mechanism. This research gives an insight into the optimized design of deformation passes in order to eliminate the unwanted wrinkling deformation in multi-pass incremental forming process.
Simple Springback Cause Analysis Using Measured Shapes of Dies and Pressed Part
Authors: Hiramoto Jiro , Urabe Masaki , Ishiwatari Akinobu , Yoshida Fusahito
Published: December 2016

A new springback cause analysis method was developed for sheet press forming with measured 3-dimentional shapes of dies and a formed part. In conventional springback cause analysis, a stress distribution is calculated by elasto-plastic FEM analysis of press forming. The newly developed method can be directly applied to a press formed part and its forming dies: an elastic FEM analysis of press forming is conducted using measured shapes of both a pressed part and forming dies, and a stress distribution which causes springback is obtained; and then a springback cause analysis is carried out based on the stress distribution. This calculation method is easier than that of conventional press forming simulation because plastic material properties and friction parameters are not required in its procedure. The philosophy of the new method and an example of application to an automotive part are described in this paper.
Comparative Research on the Crushing Behaviour of Aluminium Sheet Wrapped Square Carbon Fibre Reinforced Plastic (CFRP) Tubes
Authors: Hussein Rafea Dakhil , Ruan Dong , Lu Guo Xing
Published: December 2016

In this study, hollow square carbon fibre reinforced plastic (CFRP) tubes and aluminium sheet wrapped CFRP tubes have been axially crushed at a quasi-static loading velocity of 0.05 mm/s. A specially designed and manufactured platen with four cutting blades was used to cut and crush these two tubular structures. The four cutting blades had height of 5 mm and width of 3 mm with round tip to reduce the initial peak force and achieve a stable crushing deformation mode. Notches at one end of each tube were utilized to control the location of initial failure. The crashworthiness characteristics of hollow CFRP tubes and aluminium sheet wrapped CFRP tubes with notches that crushed by the platen with cutting blades were compared with those of tubes that crushed by a flat platen. Experimental results showed that using the platen with blades to crush the specimens with notches exhibited more stable deformation mode than the specimens without notches. Mean crushing force, energy absorption and specific energy absorption (SEA) increased when CFRP was wrapped with aluminium sheet and crushed by the platen with blades. The increase of average value of mean crushing force, energy absorption and specific energy absorption of aluminium sheet wrapped CFRP tube and crushed by the platen with blades are 16.5%, 17.3% and 5% respectively more than those for hollow tubes that crushed by a flat platen.
An Experimental Study on Axial Joint Strength Made of Fe-28Mn-6Si-5Cr Shape Memory Alloy at Various Deformation Speeds
Authors: Yamamoto Yasuhiro , Fujita Kazuki , Iwamoto Takeshi
Published: December 2016

Fe-SMA is attempted to be applied to large structural members such as pipe joints and vibration absorbers. However, if the pipe joint is used as pipelines and curved pipes in the underground, etc., it is considered that the applications require the long endurance for several loading conditions at various deformation rates. In the past, the axial strength of the pipe joint is estimated under a quasi-static tensile test at just single strain rate. However, it is hard to find papers which estimate the axial strength of the pipe joint as well as examining its rate sensitivity. In this study, at first, the pipe joint made of Fe-SMA is prepared. It is attempted to conduct a push-out test at various deformation rates and find the joint strength when a tightening function of the joint is lost. Here, the joint strength is defined by the strength when circumferential strain on the surface of joint starts decreasing. Additionally, rate sensitivity of axial strength defined is discussed.
Kinetics of Myeloid-Derived Suppressor Cell Frequency and Function during Simian Immunodeficiency Virus Infection, Combination Antiretroviral Therapy, and Treatment Interruption
Authors: Dross Sandra E. , Munson Paul V. , Kim Se Eun , Bratt Debra L. , Tunggal Hillary C. , Gervassi Ana L. , Fuller Deborah H. , Horton Helen
Published: December 2016

During chronic lentiviral infection, poor clinical outcomes correlate both with systemic inflammation and poor proliferative ability of HIV-specific T cells; however, the connection between the two is not clear. Myeloid-derived suppressor cells (MDSC), which expand during states of elevated circulating inflammatory cytokines, may link the systemic inflammation and poor T cell function characteristic of lentiviral infections. Although MDSC are partially characterized in HIV and SIV infection, questions remain regarding their persistence, activity, and clinical significance. We monitored MDSC frequency and function in SIV-infected rhesus macaques. Low MDSC frequency was observed prior to SIV infection. Post-SIV infection, MDSC were elevated in acute infection and persisted during 7 mo of combination antiretroviral drug therapy (cART). After cART interruption, we observed MDSC expansion of surprising magnitude, the majority being granulocytic MDSC. At all stages of infection, granulocytic MDSC suppressed CD4+ and CD8+ T cell proliferation in response to polyclonal or SIV-specific stimulation. In addition, MDSC frequency correlated significantly with circulating inflammatory cytokines. Acute and post-cART levels of viremia were similar, however, the levels of inflammatory cytokines and MDSC were more pronounced post-cART. Expanded MDSC during SIV infection, especially during the post-cART inflammatory cytokine surge, likely limit cellular responses to infection. As many HIV curative strategies require cART interruption to determine efficacy, our work suggests treatment interruption–induced MDSC may especially undermine the effectiveness of such strategies. MDSC depletion may enhance T cell responses to lentiviral infection and the effectiveness of curative approaches.
Epigenetic Networks Regulate the Transcriptional Program in Memory and Terminally Differentiated CD8+ T Cells
Authors: Rodriguez Ramon M. , Suarez-Alvarez Beatriz , Lavín José L. , Mosén-Ansorena David , Baragaño Raneros Aroa , Márquez-Kisinousky Leonardo , Aransay Ana M. , Lopez-Larrea Carlos
Published: December 2016

Epigenetic mechanisms play a critical role during differentiation of T cells by contributing to the formation of stable and heritable transcriptional patterns. To better understand the mechanisms of memory maintenance in CD8+ T cells, we performed genome-wide analysis of DNA methylation, histone marking (acetylated lysine 9 in histone H3 and trimethylated lysine 9 in histone), and gene-expression profiles in naive, effector memory (EM), and terminally differentiated EM (TEMRA) cells. Our results indicate that DNA demethylation and histone acetylation are coordinated to generate the transcriptional program associated with memory cells. Conversely, EM and TEMRA cells share a very similar epigenetic landscape. Nonetheless, the TEMRA transcriptional program predicts an innate immunity phenotype associated with genes never reported in these cells, including several mediators of NK cell activation (VAV3 and LYN) and a large array of NK receptors (e.g., KIR2DL3, KIR2DL4, KIR2DL1, KIR3DL1, KIR2DS5). In addition, we identified up to 161 genes that encode transcriptional regulators, some of unknown function in CD8+ T cells, and that were differentially expressed in the course of differentiation. Overall, these results provide new insights into the regulatory networks involved in memory CD8+ T cell maintenance and T cell terminal differentiation.
Performance of a driven hitch-cart for draft animal power under different power take-off torque and ballast levels condition
Authors: Masella Piernicola , Guerrini Lorenzo , Parenti Alessandro , Baldi Fabio , Spugnoli Paolo
Published: December 2016

The performance of a two-wheel driven hitch-cart designed for draft animal power has been assessed. The cart fits a three-point linkage system and a ground-driven power take-off (PTO). Conventional pneumatic tires and metallic wheels have been tested in dedicated draft trials with increasing torque applied to PTO (7.0 to 70 Nm) at two ballast levels (100 and 200 kg). Draft force varies from a minimum of about 760 N (pneumatic tires and the lowest ballast), up to about 4480 N (metallic wheels and the highest ballast), with a linear increase as a function of the PTO applied torque. In term of global efficiency the better performances was achieved in different conditions. The metallic wheels deliver greater power to the PTO than pneumatic tires. Furthermore, they had global efficiencies higher than pneumatic for high power requirements, while the pneumatics perform better when the required power is low. Slippage rises as a function of increasing torque and decreasing ballast, with metallic wheels allowing delivery of greater PTO torque at the same slippage extent. The performances of the cart are consistent with the use of implements designed for small tractors.
Reading as learning in the primary school
Authors: Henning Elizabeth
Published: December 2016

No abstract available.