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991.
992.
Openness has become an important, all‐encompassing term denoting activities facilitated by sharing, using, producing, and redistributing information and communication resources within digital information systems. We compare theoretical advancements that emphasize processes and characteristics of openness with the limitations of extant approaches that have largely focused on improvements to productivity and efficiency. Based on Foucault and Bruner's ideas, this paper contributes a new critical narrative approach to understanding openness explicitly focused on structural transformation and power. The analysis focuses on the case of open development, examining 20 key studies based primarily on developing countries. The critical narrative approach unpacked the production of power/knowledge across actors, intentions, and outcomes of openness research and practice. We find that discursive formations are reliant on technocentric and normative ideals of researchers, leading to narratives of hypothetical outcomes that exclude marginalized perspectives. We propose hermeneutic composability and contesting normative narratives of openness as analytical techniques for an integrated, mutually constitutive conception of interactions between individuals, open artefacts, and open social praxis. 相似文献
993.
Fernández-Godino M. Giselle Dubreuil Sylvain Bartoli Nathalie Gogu Christian Balachandar S. Haftka Raphael T. 《Structural and Multidisciplinary Optimization》2019,60(6):2205-2220
Structural and Multidisciplinary Optimization - When simulations are very expensive and many are required, as for optimization or uncertainty quantification, a way to reduce cost is using... 相似文献
994.
The purpose of this paper is to present an extension of the generalised supertwisting algorithm (STA) to the multivariable framework. We begin by introducing an algorithm that may be deemed as a linear, quasicontinuous, or discontinuous multivariable system, depending on the functions that define them. For the class represented by such an algorithm we prove the robust, Lyapunov stability of the origin and characterise the perturbations that preserve its stability. In particular, when its vector field is discontinuous or quasicontinuous our algorithm is endowed with finite‐time stability. Due to its resemblance to the scalar case, we denote such finite‐time stable systems as generalised multivariable STA. Furthermore, the class of finite‐time stable systems comprise the currently available versions of STAs. To finalise, by means of simulation examples, we show that our proposed finite‐time stable algorithms are well suited for signals online differentiation and highlight their dynamical traits. 相似文献
995.
Goncharenko V. I. Lebedev G. N. Mikhailin D. A. 《Journal of Computer and Systems Sciences International》2019,58(1):147-158
Journal of Computer and Systems Sciences International - This paper suggests a novel approach to online two-dimensional route planning for a coordinated flight of a group of unmanned aerial... 相似文献
996.
Multimedia Tools and Applications - Multimedia computing has evolved as a remarkable technology which provides services to view, create, edit, process, and search multimedia contents. All these... 相似文献
997.
Yassen Mahmood T. Hussan Mohammed R. Hammas Hussain A. Al-Saedi Hussam Ali Jawad K. 《Wireless Personal Communications》2019,104(2):649-662
Wireless Personal Communications - The design of a fractal based slot antenna, to serve the dual-band communication applications, is proposed in this paper. The structure of the proposed antenna is... 相似文献
998.
Wireless Personal Communications - The issues based on gastroenterology are the most distressing diseases in a human anatomy with the largest solid organ, liver that requires serious attention in... 相似文献
999.
Calcite has a highly anisotropic thermal expansion coefficient, and repeated heating and cooling cycles can potentially destabilize chalks by breaking cement bonds between neighboring particles. Based on tensile strength measurements, we investigated how temperature cycles induce weakening of chalk. Tensile strength tests were performed on chalk specimens sampled from Kansas (USA) and Mons (Belgium), each with differing amounts of contact cement. Samples of the two chalk types were tested in dry and water-saturated states, and then exposed to 0, 15, and 30 temperature cycles in order to find out under what circumstances thermally induced tensile strength reduction occurs. The testing results show that the dry samples were not influenced by temperature cycling in either of the chalk types. However, in the water-saturated state, tensile strength is increasingly reduced with progressive numbers of temperature cycles for both chalk samples, especially for the more cemented Kansas chalk. The Kansas chalk demonstrated higher initial tensile strength compared to the less cemented Mons chalk, but the strength of both chalks was reduced by the same relative proportion when undergoing thermal cycles in the water-saturated state. 相似文献
1000.
Ting Hui Yuan Zhen Hua Zhang Jin Li Da Quan Zhang Li Xin Gao Wen Ge Li Zhi Feng Fan 《工业材料与腐蚀》2019,70(7):1298-1305
In the study, polyaniline/reduced‐graphene oxide (PANI‐RGO) composites, fabricated by loading 2, 5, and 8wt% graphene oxide, was prepared by in‐situ emulsion polymerization and reduction. They are characterized by Fourier transform infrared spectroscopy, X‐ray diffraction, and scanning electron microscopy. Epoxy coatings adding PANI and PANI‐RGO composites were coated on the surface of AA5083 Al alloy. The anticorrosion performance of the coatings is measured by electrochemical impedance spectroscopy and potentiodynamic polarization curve in 3.5wt% NaCl solution. The results demonstrate that the epoxy/PANI‐RGO coating exhibits a better protection against AA5083 alloy corrosion compared with the epoxy/PANI coating. Enhancement of the passivation performance of PANI was obtained by the addition of RGO into epoxy/PANI coating system. 相似文献