bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance of Flexible Chemoresistive Gas Sensors after Having Undergone Automated Bending Tests
Authors: Alvarado Miriam , La Flor Silvia De , Llobet Eduard , Romero Alfonso , Ramírez José Luis
Published: November 2019

Many sensors are developed over flexible substrates to be used as wearables, which does not guarantee that they will actually withstand being bent. This work evaluates the gas sensing performance of metal oxide devices of three different types, before and after having undergone automated, repetitive bending tests. These tests were aimed at demonstrating that the fabricated sensors were actually flexible, which cannot be taken for granted beforehand. The active layer in these sensors consisted of WO3 nanowires (NWs) grown directly over a Kapton foil by means of the aerosol-assisted chemical vapor deposition. Their response to different H2 concentrations was measured at first. Then, they were cyclically bent, and finally, their response to H2 was measured again. Sensors based on pristine WO3-NWs over Ag electrodes and on Pd-decorated NWs over Au electrodes maintained their performance after having been bent. Ag electrodes covered with Pd-decorated NWs became fragile and lost their usefulness. To summarize, two different types of truly flexible metal oxide gas sensor were fabricated, whereas a third one was not flexible, despite being grown over a flexible substrate following the same method. Finally, we recommend that one standard bending test procedure should be established to clearly determine the flexibility of a sensor considering its intended application.
Sensitivity Improvement of Urchin-Like ZnO Nanostructures Using Two-Dimensional Electron Gas in MgZnO/ZnO
Authors: Bak So-Young , Lee Jeongseok , Kim Yoojong , Lee Se-Hyeong , Woo Kyoungwan , Lee Sanghyun , Yi Moonsuk
Published: November 2019

This paper introduces a strategy for improving the sensitivity of a gas sensor to NO2 gas. The gas sensor was fabricated using urchin-like ZnO nanostructures grown on MgO particles via vapor-phase growth and decorated with MgZnO nanoparticles via a sol-gel process. The urchin-like ZnO gas sensor decorated with MgZnO showed higher sensitivity to NO2 gas than a pristine urchin-like ZnO gas sensor. When ZnO and MgZnO form a heterojunction, a two-dimensional electron gas is generated. This improves the performance of the fabricated gas sensor. The growth morphology, atomic composition, and phase structure were confirmed through field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction, respectively.
Relative Humidity Sensors Based on Microfiber Knot Resonators—A Review
Authors: Han Young-Geun
Published: November 2019

Recent research and development progress of relative humidity sensors using microfiber knot resonators (MKRs) are reviewed by considering the physical parameters of the MKR and coating materials sensitive to improve the relative humidity sensitivity. The fabrication method of the MKR based on silica or polymer is briefly described. The many advantages of the MKR such as strong evanescent field, a high Q-factor, compact size, and high sensitivity can provide a great diversity of sensing applications. The relative humidity sensitivity of the MKR is enhanced by concerning the physical parameters of the MKR, including the waist or knot diameter, sensitive materials, and Vernier effect. Many techniques for depositing the sensitive materials on the MKR surface are discussed. The adsorption effects of water vapor molecules on variations in the resonant wavelength and the transmission output of the MKR are described regarding the materials sensitive to relative humidity. The sensing performance of the MKR-based relative humidity sensors is discussed, including sensitivity, resolution, and response time.
Recent Trends, Technical Concepts and Components of Computer-Assisted Orthopedic Surgery Systems: A Comprehensive Review
Authors: Kubicek Jan , Tomanec Filip , Cerny Martin , Vilimek Dominik , Kalova Martina , Oczka David
Published: November 2019

Computer-assisted orthopedic surgery (CAOS) systems have become one of the most important and challenging types of system in clinical orthopedics, as they enable precise treatment of musculoskeletal diseases, employing modern clinical navigation systems and surgical tools. This paper brings a comprehensive review of recent trends and possibilities of CAOS systems. There are three types of the surgical planning systems, including: systems based on the volumetric images (computer tomography (CT), magnetic resonance imaging (MRI) or ultrasound images), further systems utilize either 2D or 3D fluoroscopic images, and the last one utilizes the kinetic information about the joints and morphological information about the target bones. This complex review is focused on three fundamental aspects of CAOS systems: their essential components, types of CAOS systems, and mechanical tools used in CAOS systems. In this review, we also outline the possibilities for using ultrasound computer-assisted orthopedic surgery (UCAOS) systems as an alternative to conventionally used CAOS systems.
AttentivU: An EEG-Based Closed-Loop Biofeedback System for Real-Time Monitoring and Improvement of Engagement for Personalized Learning
Authors: Kosmyna Nataliya , Maes Pattie
Published: November 2019

Information about a person’s engagement and attention might be a valuable asset in many settings including work situations, driving, and learning environments. To this end, we propose the first prototype of a device called AttentivU—a system that uses a wearable system which consists of two main components. Component 1 is represented by an EEG headband used to measure the engagement of a person in real-time. Component 2 is a scarf, which provides subtle, haptic feedback (vibrations) in real-time when the drop in engagement is detected. We tested AttentivU in two separate studies with 48 adults. The participants were engaged in a learning scenario of either watching three video lectures on different subjects or participating in a set of three face-to-face lectures with a professor. There were three conditions administrated during both studies: (1) biofeedback, meaning the scarf (component 2 of the system) was vibrating each time the EEG headband detected a drop in engagement; (2) random feedback, where the vibrations did not correlate or depend on the engagement level detected by the system, and (3) no feedback, when no vibrations were administered. The results show that the biofeedback condition redirected the engagement of the participants to the task at hand and improved their performance on comprehension tests.
An Empirical Study on V2X Enhanced Low-Cost GNSS Cooperative Positioning in Urban Environments
Authors: Schwarzbach Paul , Michler Albrecht , Tauscher Paula , Michler Oliver
Published: November 2019

High-precision and lane selective position estimation is of fundamental importance for prospective advanced driver assistance systems (ADAS) and automated driving functions, as well as for traffic information and management processes in intelligent transportation systems (ITS). User and vehicle positioning is usually based on Global Navigation Satellite System (GNSS), which, as stand-alone positioning, does not meet the necessary requirements in terms of accuracy. Furthermore, the rise of connected driving offers various possibilities to enhance GNSS positioning by applying cooperative positioning (CP) methods. Utilizing only low-cost sensors, especially in urban environments, GNSS CP faces several demanding challenges. Therefore, this contribution presents an empirical study on how Vehicle-to-Everything (V2X) technologies can aid GNSS position estimation in urban environments, with the focus being solely on positioning performance instead of multi-sensor data fusion. The performance of CP utilizing common positioning approaches as well as CP integration in state-of-the-art Vehicular Ad-hoc Networks (VANET) is displayed and discussed. Additionally, a measurement campaign, providing a representational foundation for validating multiple CP methods using only consumer level and low-cost GNSS receivers, as well as commercially available IEEE 802.11p V2X communication modules in a typical urban environment is presented. Evaluating the algorithm’s performance, it is shown that CP approaches are less accurate compared to single positioning in the given environment. In order to investigate error influences, a skyview modelling seeking to identify non-line-of-sight (NLoS) effects using a 3D building model was performed. We found the position estimates to be less accurate in areas which are affected by NLoS effects such as multipath reception. Due to covariance propagation, the accuracy of CP approaches is decreased, calling for strategies for multipath detection and mitigation. In summary, this contribution will provide insights on integration, implementation strategies and accuracy performances, as well as drawbacks for local area, low-cost GNSS CP in urban environments.
Sustainability through the Digitalization of Industrial Machines: Complementary Factors of Fuel Consumption and Productivity for Forklifts with Sensors
Authors: Pashkevich Natallia , Haftor Darek , Karlsson Mikael , Chowdhury Soumitra
Published: November 2019

Increasing the fuel efficiency of industrial machines through digitalization can enable the transport and logistics sector to overcome challenges such as low productivity growth and increasing CO2 emissions. Modern digitalized machines with embedded sensors that collect and transmit operational data have opened up new avenues for the identification of more efficient machine use. While existing studies of industrial machines have mostly focused on one or a few conditioning factors at a time, this study took a complementary approach, using a large set of known factors that simultaneously conditioned both the fuel consumption and productivity of medium-range forklifts (n = 285) that operated in a natural industrial setting for one full year. The results confirm the importance of a set of factors, including aspects related to the vehicles’ travels, drivers, operations, workload spectra, and contextual factors, such as industry and country. As a novel contribution, this study shows that the key conditioning factors interact with each other in a non-linear and non-additive manner. This means that addressing one factor at a time might not provide optimal fuel consumption, and instead all factors need to be addressed simultaneously as a system.
Effect of pH on Rheological and Filtration Properties of Water-Based Drilling Fluid Based on Bentonite
Authors: Gamal Hany , Elkatatny Salaheldin , Basfar Salem , Al-Majed Abdulaziz
Published: November 2019

The design of drilling fluids is very important for the drilling operation success. The rheological properties play a key role in the performance of the drilling fluid. Therefore, studying the mud rheological properties of the water-based drilling fluid based on bentonite is essential. The main objectives of this study are to address the effect of pH changes on the rheological and filtration properties of the water-based drilling fluid based on bentonite and to provide a recommended pH range for this drilling fluid for a safe and high-performance drilling operation. Different samples of the water-based drilling fluid based on bentonite with different pH values were prepared, and the rheological properties such as plastic viscosity, yield point, and gel strength were measured. After that, the filtration test was performed under 300 psi differential pressure and 200 °F. The pH for the water-based drilling fluid based on bentonite significantly affects the mud rheology. The shear stress and shear rate relation were varying with the change in the pH. Increasing the pH from 8 to 12 resulted in decreasing the plastic viscosity by 53% and the yield point by 82%, respectively. The ratio of yield point / plastic viscosity was 1.4 for pH of 8 while it decreased to 0.5 for a pH of 11 and 12. There was a significant decrease in the gel strength readings by increasing the pH. The filtrate volume and filter cake thickness increased by increasing pH. The filtration volume increased from 9.5 cm3 to 12.6 cm3 by increasing the pH from 9 to 12. The filter cake thickness was 2 mm at 9 pH, while it was increased to 3.6 mm for 12 pH. It is recommended from the results to keep the pH of water-based drilling fluid based on bentonite in the range of 9 to 10 as it provides the optimum mud rheological and filtration properties. The findings of this study illustrated that keeping the pH in the range of 9 to 10 will reduce the plastic viscosity that will help in increasing the rate of penetration and reducing the required pump pressure to circulate the mud to the surface which will help to sustain the drilling operation. In addition, reducing the filtrate volume will produce a thin filter cake which will help in avoiding the pipe sticking and protect the environment. In general, optimizing the pH of the water-based drilling fluid based on bentonite in the range of 9 to 10 will improve the drilling operation and minimize the total cost.
Product Design Supporting Improved Water, Sanitation, and Energy Services Delivery in Low-Income Settings
Authors: Sharpe Taylor , Muragijimana Christian , Thomas Evan
Published: November 2019

Several approaches have been proposed in the literature supporting product design applied in low-income settings. These approaches have typically focused on individual- and household-level beneficiaries, with an emphasis on participatory, human-centered co-design methods. In this paper, we present a design approach that is, in contrast, focused on supporting providers of improved water, sanitation, and energy services. We establish requirements for design in these contexts, especially addressing design iteration. We describe sets of feedback systems between designers and various sources of expert knowledge, codifying roles of design stakeholders in this context. We demonstrate these principles across three case studies: a sanitation service monitoring technology in Kenya; a water flowmeter technology in Kenya; and a water storage monitoring technology in Sierra Leone.
Key Criteria and Competences Defining the Sustainability of Start-Up Teams and Projects in the Incubation and Acceleration Phase
Authors: Hudáková Monika , Urbancová Hana , Vnoučková Lucie
Published: November 2019

This study investigates and identifies crucial and efficient competencies of start-up founders and new business leaders, together with the identification of crucial support provided by accelerator programs. These competencies are necessary as individuals and businesses increasingly focus on innovations, industry 4.0, and technologies. This requires an innovative set of entrepreneurs´ competencies to move businesses to the next level. The study gathered data by means of a quantitative questionnaire research and interviews conducted among start-up projects in accelerator programs over the past three years (2017–2019). In total, 158 start-ups were surveyed, and 38 successful teams were interviewed during this period. To analyze results, content analysis was used and Pearson’s chi-square test and the association test were employed using descriptive and two-dimensional statistics tools. The results identified key success criteria and competencies of successful start-up teams. These include knowledge of the ecosystem, resource planning and use, an ability to move from the initial stages, awareness of communication methods, and lobbying. Our findings are that key activities leading to the acceleration of projects are raising awareness among the target group, furthering the development of contacts, facilitating more efficient use of resources, and enabling the identification of barriers to the next phase of development and ways to remove them. The results may inspire other researchers to conduct studies under other conditions to further identify and understand these entrepreneurial competencies.
Post-Mortem Analysis of Inhomogeneous Induced Pressure on Commercial Lithium-Ion Pouch Cells and Their Effects
Authors: Fuchs Georg , Willenberg Lisa , Ringbeck Florian , Sauer Dirk Uwe
Published: November 2019

This work conducts a post-mortem analysis of a cycled commercial lithium-ion pouch cell under an induced inhomogeneous pressure by using a stainless-steel sphere as a force transmitter to induce an inhomogeneous pressure distribution on a cycled lithium-ion battery. After the cycling, a macroscopic and microscopic optical analysis of the active and passive materials was executed. Also, scanning electron microscopy was used to analyze active material particles. The sphere shape results in a heterogenic pressure distribution on the lithium-ion battery and induces a ring of locally high electrochemical activity, which leads to lithium plating. Furthermore, a surface layer found on the anode, which is a possible cause of electrolyte degradation at the particle–electrolyte interface. Significant deformation and destruction of particles by the local pressure was observed on the cathode. The analysis results validate previous simulations and theories regarding lithium plating on edge effects. These results show that pressure has a strong influence on electrolyte-soaked active materials.
Sentinel-2 Satellites Provide Near-Real Time Evaluation of Catastrophic Floods in the West Mediterranean
Authors: Caballero Isabel , Ruiz Javier , Navarro Gabriel
Published: November 2019

Flooding is among the most common natural disasters in our planet and one of the main causes of economic and human life loss worldwide. Evidence suggests the increase of floods at European scale with the Mediterranean coast being critically vulnerable to this risk. The devastating event in the West Mediterranean during the second week of September 2019 is a clear case of this risk crystallization, when a record-breaking flood (locally called the “Cold Drop” (Gota Fría)) has swollen into a catastrophe to the southeast of Spain surpassing previous all-time records. By using a straightforward approach with the Sentinel-2 twin satellites from the Copernicus Programme and the ACOLITE atmospheric correction processor, an initial approximation of the delineated flooded zones, including agriculture and urban areas, was accomplished in quasi-real time. The robust and flexible approach requires no ancillary data for rapid implementation. A composite of pre- and post-flood images was obtained to identify change detection and mask water pixels. Sentinel-2 identifies not only impacts on land but also on water ecosystem and its services, providing information on water quality deterioration and concentration of suspended matter in highly sensitive environments. Subsequent water quality deterioration occurred in large portions of Mar Menor, the largest coastal lagoon in the Mediterranean. The present study demonstrates the potentials brought by the free and open-data policy of Sentinel-2, a valuable source of rapid synoptic spatio-temporal information at the local or regional scale to support scientists, managers, stakeholders, and society in general during and after the emergency.
Numerical Simulation Study on Salt Release Across the Sediment–Water Interface at Low-Permeability Area
Authors: Li Weijian , Wang Jinguo , Chen Zhou , Yang Yun , Liu Ruitong , Zhuo Yue , Yang Dong
Published: November 2019

Salt release from dredger filling sediment is a significant threat to freshwater resources in coastal regions around the world. This study focuses on the estimation of the field-scale salt-release process from the low-permeability sediment–water interface under different hydrological and hydrodynamic conditions. In situ sampling tests and physical experiments were implemented to calculate hydrogeological parameters and monitor sediment and water salinity. Numerical modeling was used to calibrate the molecular diffusion coefficient, of which the correlation coefficient was over 0.9, and explore the salt-release process across the sediment–water interface in Yuehu Lake, China. Furthermore, we discuss the influence of hydrologic conditions in terms of the lake stage and hydrodynamic conditions with water-exchange on the process of salt exchange between the sediment and water based on numerical simulations. Our findings showed that water-exchange accelerated the process of salt release from the sediment and maintained a relatively low salinity in the surface water. The salt-release rate decreased gradually as the concentration gradient between the water and sediment decreased. A frequency of water-exchange of 90 d maintained a rapid salt-release rate with fewer water-exchange steps. The influence of the lake stage was weak on the salt-release process at low-permeability area and salt release was not impeded before the salt capacity of water reached the maximum value. When the water–sediment salinity reached equilibrium, the salt-release process between the water and sediment equilibrated as the supply from the lower layers equaled the release to the water at the interface. These results are important in regard to controlling surface water salinization in coastal reclamation areas.
Study of the oxidation states and magnetic properties of iron in volcanic glasses : Lipari and Teotihuacan obsidians
Authors: Régnard Jean-René , Chavez-Rivas Fernando , Chappert Jacques
Published: November 2019

Les propriétés du fer dans les verres volcaniques telles que sa localisation dans la matrice, sa présence sous forme d'atome isolé ou d'amas d'oxyde de fer peuvent donner des informations utiles sur les conditions d'oxydo-réduction et de refroidissement de la lave ainsi que sur l'équilibre thermodynamique existant entre la phase gazeuse et les phases condensées pendant l'éruption. C'est dans ce but qu'ont été utilisées différentes techniques physiques telles que la fluorescence X, la diffraction des rayons X, la spectroscopie Mössbauer, les mesures magnétiques, la microscopie et la microsonde électronique pour l'étude de deux obsidiennes. Après contrôle de l'état amorphe, on a caractérisé les deux états de charge du fer présent dans deux obsidiennes noires provenant de Lipari (Italie) et Teotihuacan (Mexique). On montre la présence dans l'obsidienne de Lipari d'atomes de fer isolés (principalement Fe²⁺) et d'amas très fins (< 100 Å) de magnétite. Dans l'obsidienne de Teotihuacan, on observe la présence d'ions Fe²⁺ et Fe isolés (environ 50 %) et d'amas fins (100-900 Å) et très fins de magnétite (environ 50 %).
La libération de l'eau, du gaz carbonique et des hydrocarbures des cordiérites. Cinétique des mécanismes. Détermination des sites. Intérêt pétrogénétique
Authors: Zimmermann Jean-Louis
Published: November 2019

Les échantillons correspondent à différentes origines géographiques et génétiques : faciès amphibolite et granulite du Bamble (Norvège du Sud), granite du Velay (France) associé à un métamorphisme de basse pression, gneiss à antophyllite, à biotite de Madagascar, série métamorphique de très basse pression de la Cordillère Bétique (Espagne), série métamorphique de très haute pression du Rif Interne (Maroc).

Les fluides sont extraits par étuvage sous vide, 1) par paliers successifs, 2) par accroissement continu de la température, et analysés par spectrométrie de masse.

L'abondance et la nature des fluides piégés varient selon les faciès. Le gaz carbonique, l'oxyde de carbone et les composés organiques sont très abondants dans le faciès granulite. A l'inverse, bien qu'elle possède aussi des composés carbonés, la phase fluide du faciès amphibolite est essentiellement aqueuse (85 à 90 % d'H₂O contre 60 % dans le faciès granulite). En général, il y a proportionnalité entre la teneur en eau et la pression estimée de la phase aqueuse lors de la formation du minéral. L'étude cinétique du dégazage, notamment de la déshydratation, peut fournir de précieuses indications sur l'histoire thermique du minéral. En supposant que le départ de l'eau soit une réaction chimique de premier ordre, on voit que la température du taux maximum de déshydratation est dans plusieurs cas proche de la température de formation du minéral évaluée par les études pétrographiques. L'existence de plusieurs maxima peut correspondre à différents événements de l'histoire du minéral ; toutefois les impuretés des cavités structurales peuvent modifier la cinétique du dégazage.
Crystallochemistry and thermochemistry of sodi-potassic copper silicate Na2-2xK2xCuSi4O10
Authors: Kawamura Katsuyuki , Iiyama Jean Toshimichi
Published: November 2019

Il existe trois espèces distinctes dans la famille des silicates sodi-potassiques de cuivre Na[2-2x]K[2x]CuSi₄O₁₀. Les pôles sodique et potassique ne se forment que par synthèse hydrothermale tandis que le composé intermédiaire (x = 0,5) se trouve dans la nature sous le nom de litidionite. Le pôle sodique et la litidionite sont isostructuraux avec le groupe spatial P[-1]. La structure est constituée de tubes silicatés formés par les anneaux de six tétraèdres Si — O. Ils sont liés par Cu et Na. Le potassium dans la litidionite et un autre Na du pôle sodique se trouvent dans les grandes cavités de la chaîne formée par les tétraèdres. Le pôle potassique appartient au groupe P2₁m avec les tubes constitués d'anneaux de huit tétraèdres.

Les essais de réactions d'échange d'ions Na — K dans ces minéraux ont été effectués sous une pression de 1 000 bars et à 500 °C. Les résultats montrent que les solutions solides de la litidionite peuvent coexister avec les solutions dont le rapport K/(Na + K) varie dans un vaste domaine. Les solutions solides au voisinage du pôle sodique sont limitées à un rapport K(Na/K) = 0,0 ~ 0,38 dans la solution hydrothermale en équilibre avec le minéral. Le pôle potassique ne peut coexister qu'avec des solutions aqueuses extrêmement riches en K (K/(Na + K) > 0,96).

L'analyse thermodynamique de l'isotherme d'échange Na — K observé montre que les propriétés de mélange de cette famille cristalline peuvent être bien exprimées par des solutions solides régulières à deux sites avec les paramètres d'interaction b = 1,37 kcal/mole, C₁₁ = 1,75 kcal/mole et C₂₂ = 1,83 kcal/mole avec Δμ° d'échange correspondant 1,99 kcal/mole.
Experimental results bearing on the stability of the blueschist-facies minerals deerite, howieite and zussmanite, and their petrological significance
Authors: Lattard Dominique , Schreyer Werner
Published: November 2019

La deerite (Fe²⁺,Mn²⁺,Fe³⁺,Ti⁴⁺,V³⁺)₁₈ Si₁₂(O,OH)₅₀, la howieite, Na (Fe²⁺,Fe³⁺,Mn²⁺)₁₂ Si₁₂ (O,OH)₄₄ et la zussmanite, K Fe²⁺₁₃ (Si,Al)₁₈ (O,OH)₅₆ (formules simplifiées) apparaissent dans des roches métamorphiques ferrifères appartenant presque exclusivement à des formations du faciès des « schistes bleus ».

Des études expérimentales à hautes pressions (7-30 kbar), dans des conditions hydrothermales, ont abouti à la synthèse de la ferri-deerite, Fe²⁺₁₂ Fe³⁺₆ Si₁₂ O₄₀(OH)₁₀, alors que celles de la howiéite et de la zussmanite n'ont pu être réalisées à cause de l'extrême lenteur des réactions mises en jeu. Cependant, des expériences de déstabilisation sur des spécimens naturels démontrent sans équivoque que les trois minéraux ne sont stables qu'à basses températures. La courbe de déstabilisation d'une ferri-deerite en orthoferrosilite + magnétite + quartz + H₂O a été déterminée de façon réversible depuis 500 °C-17 kbar jusqu'à 600 °C-28 kbar, environ. Une zussmanite naturelle se déstabilise à partir d'environ 530 °C -25 kbar à 580 °C-15 kbar, aussi bien en présence du tampon Fe/« FeO » qu'avec le tampon Ni/NiO. La limite maximale de stabilité d'une howieite naturelle, contenant Fe²⁺, Fe³⁺, Mn²⁺, varie sensiblement avec la fugacité d'oxygène : pour des pressions de 10 à 25 kbar, le minéral se déstabilise à partir de 460 °C en présence du tampon Fe/Fe₃O₄, mais seulement à partir de 490 °C dans le cas du tampon Ni/NiO.

L'extrapolation des résultats expérimentaux à des pressions plus faibles, comparables à celles qui règnent dans la croûte terrestre, indique que la deerite, la howieite et la zussmanite ont des domaines de stabilité qui se superposent largement à ceux des minéraux typiques du faciès des « schistes bleus ». Un examen des paragenèses observées dans des roches ferrifères formées à des pressions basses ou moyennes suggère également une limitation aux hautes pressions des champs de stabilité des trois minéraux.
A model for fluids in metamorphosed ultramafic rocks III. Mass transfer under amphibolite facies conditions in olivine˗enstatite rocks of the Central Alps, Switzerland
Authors: Pfeifer Hans-Rudolf
Published: November 2019

Le domaine le plus fortement métamorphique de la zone pennique des Alpes centrales est caractérisé par la présence de lentilles ultramafiques métriques à hectométriques d'origine harzburgitique. On observe dans celles-ci une zonation souvent concentrique indiquant une altération hydrothermale liée au métamorphisme régional. Du centre au bord, cinq zones ont été distinguées : 1) roche originale (olivine-enstatite-chlorite-Fe-Cr-Spinelle), 2) zone hydratée (olivine-talc-chlorite-Cr-Fe-spinelle), 3) zone hydratée et carbonatée (talc-magnésite-chlorite-amphibole-Fe-spinelle), 4) zone fortement enrichie en Ca, Al et Si (amphibole-chlorite-Fe-spinelle ± magnésite-pentlandite), 5) zone marginale complexe (diverses zones mono-et biminérales à biotite, amphibole ou plagioclase). Les limites de chaque zone sont très spectaculaires et significatives ; elles permettent de reconstruire les réactions d'interaction entre le fluide et la toche. Sur la base de conditions de température et de pression de 580-650 °C et 5 kbar, la composition du fluide dans les diverses zones peut être déduite et nous constatons que CO₂, O₂ et S₂ augmentent vers l'extérieur des lentilles, X[CO₂] variant entre 0 et 0,9. Les concentrations des espèces aqueuses telle que SiO₂, Ca, Al et Mg augmentent également vers l'extérieur. Le pH varierait entre 5 et 7. A partir de critères de terrain et d'hypothèses sur les modifications de volume et de masse de chaque zone, le sens et la quantité de transferts de masse sont déterminés. Alors que Mg et Fe resteraient constants, de grandes quantités de Si, Al et Ca d'origine externe pénétreraient dans les lentilles ultramafiques en provoquant jusqu'à 30 % d'augmentation de volume. Le fait que les roches encaissantes (gneiss, amphibolite, marbre) ne soient guère altérées indique une origine plus lointaine de la phase fluide, ce qui est confirmé par des analyses d'isotopes stables. Le mécanisme dominant de transport des espèces aqueuses serait celui d'infiltration dans la direction du gradient de pression de la phase fluide. Localement, à la limite des zones, le changement de la composition avec la distance de certains minéraux indique une combinaison de diffusion et infiltration.
La géochimie isotopique du faciès granulite du Bamble (Norvège) et l'origine des fluides carbonés dans la croûte profonde
Authors: Pineau Françoise , Javoy Marc , Behar Françoise , Touret Jacques
Published: November 2019

Les diverses espèces carbonées existant dans les roches caractéristiques du faciès granulite de Bamble (Norvège) ont été séparées et analysées isotopiquement dans le but de déterminer la part du carbone d'origine crustale et celle qui peut être attribuée au manteau. Les inclusions fluides préservées dans les cristaux de quartz ont un δ¹³C bas, caractéristique du carbone crustal de cette région de socle riche en matière organique. Elles sont le témoin de la phase prograde du métamorphisme. D'après les isotopes de l'oxygène, les carbonates synmétamorphiques tardifs ont fixé un équilibre isotopique correspondant à une température de 400 à 700 °C. Les δ¹³C variant de — 11,6 à — 4,3 sont les témoins de l'influence grandissante du CO₂ mantélique. Les hypérites (roches basiques intrusives amphibolitisées) sont caractérisées par une phase carbonatée de δ¹³C égal à — 8,2 ± 1 ‰ et par une phase carbonée libérée uniquement à la fusion représentant de 60 à 90 % du carbone total. Ce carbone correspond probablement au carbone dissous dans le magma au moment de sa mise en place et préservé dans le réseau d'un ou plusieurs minéraux silicatés.
Le monde celtique au IIIe siècle av. J.-C. Rapport sur les recherches récentes
Authors: Szabó Miklós
Published: November 2019

The Celtic world in the 3rd century B.C. Report on recent research.

The eastward shift in the centre of gravity of the Celtic world was a determining factor in the history of the 3rd century. The Balkan invasion of 280/279 B.C. is to be integrated into this context because of its colonizing nature. The consequences of the defeat in Greece manifested themselves throughout a vast area stretching from the British Isles and Central Anatolia to the plains of Northern Europe and the Mediterranean by the formation of new units (the Scordisci, the kingdom of Tylis in Thrace, the Galatae of Asia Minor) and also by the influence exerted upon the western territories by the new eastern centre of La Tène civilization. The structural mutation of the Celtic World was accelerated by direct contacts with the Mediterranean. The transformation of the Celtic army and the change in military equipment and, similarly, the appearance of public sanctuaries, the beginning of Celtic coinage and the golden age of La Tène art are inseparable from the historical context of the 3rd century B.C.
L’apparition des grands sanctuaires au IIIe siècle avant notre ère
Authors: Lejars Thierry
Published: November 2019

L’apparition des grands sanctuaires, avec de riches dépôts, est certainement le phénomène le plus frappant du IIIe siècle av. J.-C. dans les régions occidentales du monde celtique : Picardie, Pays de Loire, Poitou-Charentes et Bretagne.

Le problème de l’origine de ces sanctuaires est abordé à partir de l’examen de certains aspects rituels ainsi que de l’analyse des mobiliers les plus anciens.

L’invention de cette forme de sanctuaire qui conduira au fanum d’époque romaine, ne peut être dissociée des mouvements de populations qui caractérisent l’Europe celtique des IVe et IIIe siècles av. J.-C.
The earliest insular Celtic art : Some unanswered questions
Authors: Megaw John Vincent Stanley , Megaw Ruth
Published: November 2019

Le premier art celtique insulaire : quelques questions sans réponse.

Depuis qu’Arthur Evans a, le premier, discuté de la nature de l’art insulaire de l’Age du Fer, en 1895, les relations entre les Iles Britanniques et le Continent à l’époque pré-romaine sont restées un acquis reconnu de l’archéologie celtique. Cependant, il y a moins de certitude dans les tentatives qui ont été faites pour mettre à jour les mécanismes dans lesquels ces relations supposées auraient fonctionné. Par exemple, tandis que l’on s’accorde en général sur les apports des styles “végétal” (Waldalgesheim) et “des épées”, on continue de regretter l’absence de définitions précises pour ces modèles tels qu’ils apparaissent dans l’art insulaire.

Cette communication passe en revue brièvement la bibliographie des quarante dernières années, en remarquant que la liste des importations continentales anciennes assurées reste réduite et souvent problématique. D’autre part, le résultat des études récentes faites sur la zone de la “culture d’Arras”, dans le Nord-Est de l’Angleterre, confirme que cette région avait une production probablement aussi ancienne que tout autre art laténien des Iles Britanniques.
L’importance de la Bohême au IIIe siècle av. J.-C. à la lumière de la recherche archéologique récente
Authors: Motyková-Šneidrová Karla
Published: November 2019

The importance of Bohemia in the 3rd century B. C. in the light of recent archaeological research.

A new rise begins in Bohemia in the 3rd century B.C. and continues in the following century by reaching its climax with the oppida civilization. Though it is beyond doubt that the decisive social layer, in this period too, was the military one, there are significative changes in the whole economical area. One has to underline, in particular, the importance of siderurgy, its influence on the development of agriculture (ploughshares, scythes) and consequently probably also on the rise of population number. Distinguished works of arts by ornaments-makers, which often combine different technics, a completely specific production of sapropelite ornaments together with direct importations are witnesses to the high demands of the élite.

An other indication of the importance of Bohemia in the 3rd century B.C. is the exceptional discovery of a clay table, designed in all probability for the melting of coin flans. This was found in the filling of a hut, scooped on an open dwelling-place near Tuchlovice in Central Bohemia.
Entre l’utile et l’art. Les fibules laténiennes en Roumanie
Authors: Zirra Vlad Vintilă
Published: November 2019

La distribution et les variations typologiques des fibules laténiennes connues du territoire de l’actuelle Roumanie reflètent de manière emblématique l’adoption très progressive, par les populations indigènes, de certains éléments culturels introduits à la suite de l’installation de groupes Celtiques en Transylvanie dans la seconde moitié du IVe siècle av. J.-C.
Christianisme et conscience européenne
Authors: Wackenheim Charles
Published: November 2019

Charles Wackenheim : Christianity and the European conscience. If Christianity has exerted a major influence on the European conscience, other sources have contributed to its making : Graeco-Roman culture, Judaism, Islam, and the considerable two-way flow in the relationships between European expansionism and non-European peoples. Consequently, any idea of a «Christian» re-building of Europe is a matter of ideological fiction rather than a realistic appreciation of historical data.
A l'ordre du jour des futurs dialogues œcuméniques
Authors: Birmelé André
Published: November 2019

Partant du constat que la plupart des questions traditionnellement controversées entre Eglises ont fait l'objet d'un dialogue fructueux dans les dernières années , cette étude réfléchit au passage d'un ensemble d'accords à un accord d'ensemble. Un ensemble de consensus partiels exige une nouvelle réflexion sur le modèle d'unité, la levée des condamnations historiques et la qualité des différences subsistantes. La deuxième partie de l'article trace certaines pistes pour le nécessaire dialogue sur les enjeux éthiques. Le large consensus doctrinal doit nécessairement trouver sa traduction éthique qui sera révélatrice de la véracité des consensus aujourd'hui affirmés.
Le lieu ecclésial et liturgique de l'acte du baptême
Authors: Siegwalt Gérard
Published: November 2019

La présente contribution sur la question du baptême veut être un hommage à André Benoît, non simplement formellement mais substantiellement, en ce qu'elle essaye d'intégrer à la réflexion systématique l'apport de la patristique dont l'auteur lui doit en premier lieu l'amour qu'il a pour elle. A l'historien, cette réflexion n'apprendra rien, sinon qu'elle le confortera dans la conscience que l'histoire de l'Eglise est, selon sa vérité, celle d'une tradition vivante, de la traditio de la substance de l'évangile du Christ reçue, vécue et attestée par l'Eglise dans des formes concrètes auxquelles l'évangile la pousse et dont, comme de l'évangile lui-même, elle a à répondre.

Le texte est un extrait d'une réflexion plus vaste sur le baptême chrétien et veut situer l'acte du baptême dans l'Eglise en tant que lieu de vie centré sur le « mystère » du Christ tel qu'il est célébré dans la liturgie. Il montre les implications de cela pour la compréhension même du catéchuménat.
Les enfants d'Abraham ou les chemins de la promesse et de la liberté. Exégèse de Galates 4,21-31
Authors: Wagner Guy
Published: November 2019

«Abraham's children or the ways of promise and freedom» : exegesis of Galatians 4,21-31.

Galatians 4,21-31 is an allegorical tale in so far as Paul uses characters from Genesis to explain the mishaps in the materializing of the promise made to Abraham. Like Agar, Israel turns to Sinai in search of salvation and consequently fails to recognize its Christ. This is close to the approach of pagan religion (stoichein and stoicheia). The episode is thus the conclusion to chapters 3 and 4 and a natural unit of the epistle. The alliance predicted by the Scriptures comes from heaven with the resurrection of the Crucified one as foreseen in Isaiah 52,13 -54,1.
Les orants dans l'art funéraire du christianisme ancien (suite)
Authors: Prigent Pierre
Published: November 2019

Les orants de l'art paléo-chrétien sont d'abord des images symboliques impersonnelles qui affirment, de manière générale, la victoire sur la mort : outre tombe la vie nouvelle s'exprime parfaitement dans la prière d'action de grâce.

Il arrive cependant, et de plus en plus souvent au fil des ans, que l'image cherche à représenter un défunt nettement individualisé pour proclamer qu'il a accédé au statut céleste que Dieu lui accorde.
Ségrégationnisme et intégrationnisme comme mobiles sous-jacents à l'antinomie de Dt 14,21 et Lv 17,15-16
Authors: Cohen Matty
Published: November 2019

Segregation and integration as motives underlying the antinomy of Dt 14-21 and Lv 17, 15-16.

The automatic prohibition underlying impurity laws of the Priest Codex invalidates the thesis of modern exegetes maintaining that D is the only document which forbids the nebelah. The antinomy between Dt 14-21 and Lv 17, 16-17 is the corollary of the ideological and theological divergences of D and Ρ codes.
La cultura empresarial y su relación con los estilos de aprendizaje en la industria de celulosa, cartón y papel en méxico
Authors: Ignacio Gómez Romero José Gerardo , Villarreal Solís María Deyanira , Villarreal Solís Francisco Martín
Published: November 2019

Este trabajo diagnostica la cultura empresarial dominante y los estilos de aprendizaje preponderantes, asimismo analiza la relación existente entre ambos conceptos en la industria de celulosa, cartón ypapel en México, dado que en la actualidad el aprendizaje es un recurso valioso para las organizaciones, de manera tal que descubrir su estilo de aprendizaje en el entorno de la cultura es un factor que favorece la supervivencia en el volátil contexto actual.
Se aplicó un instrumento a más de 400 directivos en 25 plantas en 15 estados del país, y los datos obtenidos se analizaron con ANOVAS y regresión lineal. Se diagnosticaron la cultura y los estilos de aprendizaje dominantes, se encontraron relaciones entre determinados tipos de cultura y los estilos de aprendizaje organizacional.
Eficiencia de proyectos de desarrollo de software y modelos de conversión de funcionalidad
Authors: Chávez Arellano Ricardo , Pineda Domínguez Daniel , Cuadrado Gallego Juan José
Published: November 2019

La industria del software es fundamental en el funcionamiento de la sociedad y las organizaciones de nuestro tiempo. Éstas invierten en sistemas de información para su administración de manera automatizada, lo cual requiere un proyecto de desarrollo de sistemas que se produce en la industria del software bajo el nuevo paradigma conocido como Agile. El objetivo de esta investigación fue desarrollar un modelo de conversión entre el método común de medición de funcionalidad de software de Puntos de función de IFPUG y el de Puntos de relato de Agile, obteniéndose nueve modelos de conversión entre ambas metodologías y cuyo uso ayudará a ser más eficientes los proyectos de
desarrollo de software.
La responsabilidad social interna, estudio analítico para las plantas maquiladoras
Authors: López Torres Virginia Guadalupe , Moreno Moreno Luis Ramón , Marín Vargas María Enselmina
Published: November 2019

El estudio analiza la responsabilidad social interna de las plantas maquiladoras, específicamente:
salario, salud y seguridad en el trabajo. Los sujetos de estudio son los obreros y las plantas. Para la
recolección de datos se utilizó un cuestionario y las guías de LEST y RULA. Los resultados ilustran que
el medio ambiente y las prácticas de trabajo son nocivos para la salud ocupacional del obrero, que las
empresas no otorgan beneficios adicionales a sus trabajadores; lo que significa que sus prácticas de
responsabilidad social interna son nulas. Hechos que demandan que el Estado sea un contrapoder
que vigile la conducta de dichas empresas y valore el hacer de la RS interna una nueva fuente de
derecho.
Desempeño competitivo del sector agroindustrial en el estado de Michoacán
Authors: Delfín Ortega Odette V. , Bonales Valencia Joel
Published: November 2019

Este artículo presenta el resultado de una investigación realizada sobre el sector agroindustrial de productos alimenticios procesados de exportación en el estado de Michoacán. El objetivo es determinar el impacto de la calidad, el precio, la innovación tecnológica, la gestión ambiental, el mercado y las políticas públicas agroindustriales en la competitividad internacional del sectoragroindustrial de Michoacán.
Se llevó a cabo una revisión teórica, donde se identificaron las variables y se constató que son pocos los estudios que se han realizado de la agroindustria en Michoacán. Por lo que el artículo proporciona un aporte para la toma de decisiones en el diseño de las políticas públicas del sector agroindustrial.
Para poder medir la competitividad se utilizó un cuestionario compuesto por 80 ítems que se aplicó a 51 empresas exportadoras identificadas del sector. Para el procesamiento de información se utilizó la escala tipo Likert. Una vez procesada la información se utilizaron diferentes programas y técnicas estadísticas (análisis correlacional, regresión lineal, etcétera). Con los resultados obtenidos se identificó el grado de correlación que existe entre las variables, sobresaliendo la variable mercado.
También se constató que existe competitividad en el sector, excepto por las políticas públicas agroindustriales que mostró una baja competitividad.
The Many Styles of Learning Styles Research: A Response to Fallace (2019)
Authors: Doroudi Shayan
Published: November 2019

Fallace (2019) claims that the notion of learning styles has roots in ethnocentrism. While some of the work on learning styles research does indeed seem ethnocentric, neither was this work the earliest work on learning styles nor was it seemingly influential on much of the later research on learning styles.
ANALISIS SISTEM AKUNTANSI INSTANSI PADA KANTOR PERWAKILAN BADAN KEPENDUDUKAN DAN KELUARGA BERENCANA NASIONAL PROVINSI SULAWESI UTARA
Authors: Worung Yefie Ignasia , Morasa Jenny , Tinangon Jantje
Published: November 2019

The central government is a party that is given the responsibility and rights to run the government systems, and social services to the society. In order to fulfill these duties, central government needs a system that can assist the government in carrying out its functions. Accounting Institution System is one embodiment of the systems of government that regulate the flow of goods, services and funds into supporting the implementation of the government's job. The purpose of this study is to analyze the suitability of the SAI management system procedures and regulations, analyze the course of the reconciliation process, and analyze the use of information systems related to Accounting Institution System on BKKBN SULUT. The analytical method used is descriptive comparative method which is a method for finding answers fundamentally about causation by analyzing factors of occurrence or the appearance of certain phenomena. The results showed that the organizational structure has described the separation of responsibilities and authority, especially the things related to the SAI that consist of SAK and SIMAK-BMN, the implementation of the SAI in BKKBN SULUT has not been fully implemented in accordance with applicable regulations, both internal and external reconciliation generally been accomplished by the procedure and only experienced by technical errors, while the information relating to the SAI system has been implemented properly and structured.