444 research outputs found

    I-surfaces with one T-singularity

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    We classify normal stable surfaces with KX2=1, pg= 2 and q= 0 with a unique singular point which is a non-canonical T-singularity, thus exhibiting two divisors in the main component and a new irreducible component of the moduli space of stable surfaces M¯ 1 , 3

    Structure and Strength of Dislocation Junctions: An Atomic Level Analysis

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    The quasicontinuum method is used to simulate three-dimensional Lomer-Cottrell junctions both in the absence and in the presence of an applied stress. The simulations show that this type of junction is destroyed by an unzipping mechanism in which the dislocations that form the junction are gradually pulled apart along the junction segment. The calculated critical stress needed for breaking the junction is comparable to that predicted by line tension models. The simulations also demonstrate a strong influence of the initial dislocation line directions on the breaking mechanism, an effect that is neglected in the macroscopic treatment of the hardening effect of junctions.Comment: 4 pages, 3 figure

    Mesoscopic Analysis of Structure and Strength of Dislocation Junctions in FCC Metals

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    We develop a finite element based dislocation dynamics model to simulate the structure and strength of dislocation junctions in FCC crystals. The model is based on anisotropic elasticity theory supplemented by the explicit inclusion of the separation of perfect dislocations into partial dislocations bounding a stacking fault. We demonstrate that the model reproduces in precise detail the structure of the Lomer-Cottrell lock already obtained from atomistic simulations. In light of this success, we also examine the strength of junctions culminating in a stress-strength diagram which is the locus of points in stress space corresponding to dissolution of the junction.Comment: 9 Pages + 4 Figure

    X-ray absorption spectroscopy study of diluted magnetic semiconductors: Zn1-xMxSe (M = Mn, Fe, Co) and Zn1-xMnxY (Y = Se, Te)

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    We have investigated 3d electronic states of doped transition metals in II-VI diluted magnetic semiconductors, Zn1-xMxSe (M = Mn, Fe, Co) and Zn1-xMnxY (Y = Se, Te), using the transition-metal L2,3-edge X-ray absorption spectroscopy (XAS) measurements. In order to explain the XAS spectra, we employed a tetragonal cluster model calculation, which includes not only the full ionic multiplet structure but also configuration interaction (CI). The results show that CI is essential to describe the experimental spectra adequately, indicating the strong hybridization between the transition metal 3d and the ligand p orbitals. In the study of Zn1-xMnxY (Y = Se, Te), we also found considerable spectral change in the Mn L2,3-edge XAS spectra for different ligands, confirming the importance of the hybridization effects in these materials.Comment: This paper consists of 22 pages including 4 figures. This paper is submitted to Physical Review

    Learning Mechanics and Game Mechanics Under the Perspective of Self-Determination Theory to Foster Motivation in Digital Game Based Learning

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    Background: Using digital games for educational purposes has been associated with higher levels of motivation among learners of different educational levels. However, the underlying psychological factors involved in digital game based learning (DGBL) have been rarely analyzed considering self-determination theory (SDT, Ryan \& Deci, 2000b); the relation of SDT with the flow experience (Csikszentmihalyi, 1990) has neither been evaluated in the context of DGBL

    Schottky barrier heights at polar metal/semiconductor interfaces

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    Using a first-principle pseudopotential approach, we have investigated the Schottky barrier heights of abrupt Al/Ge, Al/GaAs, Al/AlAs, and Al/ZnSe (100) junctions, and their dependence on the semiconductor chemical composition and surface termination. A model based on linear-response theory is developed, which provides a simple, yet accurate description of the barrier-height variations with the chemical composition of the semiconductor. The larger barrier values found for the anion- than for the cation-terminated surfaces are explained in terms of the screened charge of the polar semiconductor surface and its image charge at the metal surface. Atomic scale computations show how the classical image charge concept, valid for charges placed at large distances from the metal, extends to distances shorter than the decay length of the metal-induced-gap states.Comment: REVTeX 4, 11 pages, 6 EPS figure

    Particle-Size-Induced Valence Changes in Samarium Clusters

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    Samarium clusters exhibit mixed-valence behavior which is sensitive to particle size. XPS and UPS data show samarium to be primarily divalent (4f{sup 6} ) at small particle size. The trivalent state (4f{sup 5} ) becomes progressively more abundant with increasing s1ze, becoming the dominant state for the bulk metal. These results are interpreted using a model in which band narrowing, due to reduced surface coordination, is more dominant than surface tension effects in establishing the valence of small samarium clusters

    Enhancing the sustainability performance of Agri-Food Supply Chains by implementing Industry 4.0

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    [EN] In order to enhance the sustainability in the supply chain, its members should define and pursue common objectives in the three dimensions of the sustainability (economic, environmental and social). The Agri-Food Supply Chain (AFSC) is a network of different members such as farmers (producers), processors and distributors (wholesales, retailers.), etc.. In order to achieve the performance objectives of the AFSC, Industry 4.0 technologies can be implemented. The aim of this paper is to present a classification of these technologies according to two criteria: objective to be achieved (environmental or social) specified in the main issues to be covered in each objective and member of the AFSC supply chain where it is implemented. In this work, we focus on technologies that deal with environmental and social sustainability because economic sustainability will depend on the specific characteristics of the business (a supply chain using a specific Industry 4.0 technology may be profitable while others do not).This work has been funded by the Project GV/2017/065 "Development of a decision support tool for the management and improvement of sustainability in supply chains" funded by the Regional Government of Valencia. Authors also acknowledge the Project 691249, RUC-APS: Enhancing and implementing Knowledge based ICT solutions within high Risk and Uncertain Conditions for Agriculture Production Systems.Pérez Perales, D.; Verdecho Sáez, MJ.; Alarcón Valero, F. (2019). Enhancing the sustainability performance of Agri-Food Supply Chains by implementing Industry 4.0. IFIP Advances in Information and Communication Technology. 568:496-503. https://doi.org/10.1007/978-3-030-28464-0_43S496503568Camarinha-Matos, L.M., Fornasiero, R., Afsarmanesh, H.: Collaborative networks as a core enabler of Industry 4.0. In: Camarinha-Matos, L.M., Afsarmanesh, H., Fornasiero, R. (eds.) PRO-VE 2017. IAICT, vol. 506, pp. 3–17. Springer, Cham (2017). https://doi.org/10.1007/978-3-319-65151-4_1Stich, V., Gudergan, G., Zeller, V.: Need and solution to transform the manufacturing industry in the age of Industry 4.0 – a capability maturity index approach. In: Camarinha-Matos, L.M., Afsarmanesh, H., Rezgui, Y. (eds.) PRO-VE 2018. IAICT, vol. 534, pp. 33–42. Springer, Cham (2018). https://doi.org/10.1007/978-3-319-99127-6_3Flores, M., Maklin, D., Golob, M., Al-Ashaab, A., Tucci, C.: Awareness towards Industry 4.0: key enablers and applications for internet of things and big data. In: Camarinha-Matos, L.M., Afsarmanesh, H., Rezgui, Y. (eds.) PRO-VE 2018. IAICT, vol. 534, pp. 377–386. Springer, Cham (2018). https://doi.org/10.1007/978-3-319-99127-6_32Seuring, S., Müller, M.: From a literature review to a conceptual framework for sustainable supply chain management. J. Clean. Prod. 16, 1699–1710 (2008)Prima, W.A., Xing, K., Amer, Y.: Collaboration and sustainable agri-food supply chain: a literature review. In: MATEC (2016). https://doi.org/10.1051/matecconf/20165802004Pérez Perales, D., Alarcón Valero, F., Drummond, C., Ortiz, Á.: Towards a sustainable agri-food supply chain model. The case of LEAF. In: Ortiz, Á., Andrés Romano, C., Poler, R., García-Sabater, J.-P. (eds.) Engineering Digital Transformation. LNMIE, pp. 333–341. Springer, Cham (2019). https://doi.org/10.1007/978-3-319-96005-0_40Savastano, M., Amendola, C., Bellini, F., D’Ascenzo, F.: Contextual impacts on industrial processes brought by the digital transformation of manufacturing: a systematic review. Sustainability 11, 891 (2019)Varela, L., Araújo, A., Ávila, P., Castro, H., Putnik, G.: Evaluation of the relation between lean manufacturing, Industry 4.0, and sustainability. Sustainability 11, 1439 (2019)Bonilla, S.H., Silva, H.R.O., da Silva, M.T., Gonçalves, R.F., Sacomano, J.B.: Industry 4.0 and sustainability implications: a scenario-based analysis of the impacts and challenges. Sustainability 10, 3740 (2018)Bányai, T., Tamás, P., Illés, B., Stankeviciute, Z., Bányai, A.: Optimization of municipal waste collection routing: impact of Industry 4.0 technologies on environmental awareness and sustainability. Int. J. Environ. Res. Public Health. 16, 634 (2019)Lin, K.C., Shyu, J.Z., Ding, K.: A cross-strait comparison of innovation policy under Industry 4.0 and sustainability development transition. Sustainability 9, 786 (2017)Kamble, S.: Sustainable Industry 4.0 framework: a systematic literature review identifying the current trends and future perspectives. In: Process Safety and Environmental Protection Transactions of the Institution of Chemical Engineers, Part B, vol. 117, pp. 408–25. Institution of Chemical Engineers (2018)Franciosi, C., Iung, B., Miranda, S., Riemma, S.: Maintenance for sustainability in the Industry 4.0 context: a scoping literature review. IFAC-Pap. Online 51(11), 903–908 (2018)Bocken, N.M.P., Short, S.W., Rana, P., Evans, S.: A literature and practice review to develop sustainable business model archetypes. J. Clean. Prod. 65, 42–56 (2014)Bourlakis, M., Maglaras, G., Aktas, E., Gallear, D., Fotopoulos, C.: Firm size and sustainable performance in food supply chains: insights from Greek SMEs. Int. J. Prod. Econ. 152, 112–130 (2014)Garbie, I.H.: An analytical technique to model and assess sustainable development index in manufacturing enterprises. Int. J. Prod. Res. 52(16), 4876–4915 (2014)Beier, G., Niehoff, S., Ziems, T., Xue, B.: Sustainability aspects of a digitalized industry - a comparative study from China and Germany. Int. J. Precis. Eng. Manuf. Green Technol. 4, 227–234 (2017)Pérez, D., Verdecho, M.J., Alarcón, F: Industry 4.0 for the development of more sustainable decision support tools for agri-food supply chain management. In: 13rd International Conference on Industrial Engineering and Industrial Management, XXIII, Gijón, Spain (2019)Xiaolin, L., Linnan, Y., Lin, P., Wengfeng, L., Limin, Z.: Procedia engineering county soil fertility information management system based on embedded GIS. Procedia Eng. 29, 2388–2392 (2012)Satyanarayana, G.V.: Wireless sensor based remote monitoring system for agriculture using ZigBee and GPS. In: 2013 (CAC2S), pp. 110–114 (2013)Phillips, A.J., Newlands, N.K., Liang, S.H.L., Ellert, B.H.: Integrated sensing of soil moisture at the field-scale: measuring, modeling and sharing for improved agricultural decision support. Comput. Electron. Agric. 107, 73–88 (2014)Liopa-tsakalidi, A., Tsolis, D., Barouchas, P.: Application of mobile technologies through an integrated management system for agricultural production. Procedia Technol. 8, 165–170 (2013). (Haicta)Yerpude, S., Singhal, T.K.: Impact of Internet of Things (IoT) data on demand forecasting. Indian J. Sci. Technol. 10, 5 (2017)Wolfert, S., Ge, L., Verdouw, C., Bogaardt, M.: Big data in smart farming – a review. Agric. Syst. 153, 69–80 (2017)Castka, P., Balzarova, M.A.: ISO 26000 and supply chains-on the diffusion of the social responsibility standard. Int. J. Prod. Econ. 111(2), 274–286 (2008)Stock, T., Obenaus, M., Kunz, S., Kohl, H.: Industry 4.0 as enabler for a sustainable development: A qualitative assessment of its ecological and social potential. Process. Saf. Environ. 118, 254–267 (2018)Verdecho, M.J., Pérez, D., Alarcón F.: Proposal of a customer-oriented sustainable balanced scorecard for agri-food supply chains. In: 12th International Conference on Industrial Engineering and Industrial Management, Girona, Spain, 12–13 July (2018)Valcour, P.M., Hunter, L.W.: Technology, organizations, and work-life integration. In: Kossek, E.E. Lambert, S.J. (eds.), Work and Life Integration: Organizational, Cultural, and Individual Perspectives, pp. 61–84. Lawrence Erlbaum Associates, Mahwah (2005)Arntz, M., Gregory, T., Zierahn, U.: The risk of automation for jobs in OECD countries: a comparative analysis. In: OECD Social, Employment and Migration Working Papers, no. 189. OECD Publishing, Paris (2016)Grubert, J., Langlotz, T., Zollmann, S., Regenbrecht, H.: Towards pervasive augmented reality: context-awareness in augmented reality. IEEE Trans. Vis. Comput. Graph. 23, 1 (2016)Velthuis, A.G.J.: New Approaches to Food-Safety Economics. Kluwer Academic Publishers, Dordrecht (2003)Sándor, Z.P., Csiszár, C.: Development stages of intelligent parking information systems for trucks. Acta Polytechnica Hungarica 10(4), 161–174 (2013)Scognamiglio, V., Arduini, F., Palleschi, G., Rea, G.: Biosensing technology for sustainable food safety. Trends Analyt. Chem. 62, 1–10 (2014)Brynjolfsson, E., McAfee, A.: The Second Machine Age. Work, Progress, and Prosperity in a Time of Brilliant Technologies. W.W. Norton & Company, London (2014)Smith, A., Caiazza, T.: Automation in everyday life (2017). http://assets.pewresearch.org/wpcontent/uploads/sites/14/2017/10/03151500/PI_2017.10.04_Automation_FINAL.pdfHefferon, K.L.: Nutritionally enhanced food crops; progress and perspectives. Int. J. Mol. Sci. 16, 3895–3914 (2015)Glass, S., Fanzo, J.: Genetic modification technology for nutrition and improving diets: an ethical perspective. Curr. Opin. Biotech. 44, 46–51 (2017)Moe, T.: Perspectives on traceability in food manufacture’. Trends Food Sci. Technol. 9(5), 211–214 (1998)Latino, M., Corallo, A., Menegoli, M.: From Industry 4.0 to Agriculture 4.0: how manage product data in agri-food supply chain for voluntary traceability, a framework proposed. In: 20th International Conference on Food and Environment (ICFE), Rome (2018)Linus, U.O.: Traceability in agriculture and food supply chain: a review of basic concepts, technological implications, and future prospects. J. Food Agric. Environ. 1(1), 101–106 (2003)Maumbe, B.M., Okello, J.: Uses of information and communication technology (ICT) in agriculture and rural development in Sub-Saharan Africa: experiences from South Africa and Kenya. IJICTRDA 1(1), 1–22 (2010)Dlodlo, N., Kalezhi, J.: The internet of things in agriculture for sustainable rural development. In: International Conference on Emerging Trends in Networks and Computer Communications (ETNCC) (2015
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