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41.
Abdouli Khouloud Cherif W. Valent M. A. Graça M. P. F. Ktari L. Messaoudi O. Elgharbi S. Elsofany W. I. 《Journal of Materials Science: Materials in Electronics》2021,32(17):22106-22118
Journal of Materials Science: Materials in Electronics - This paper reports the effect of chromium’s substitution in magnetic oxides with perovskite structure La0.5Sm0.2Sr0.3Mn1-xCrxO3... 相似文献
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Through the diversity of criteria and stakes, the uncertain nature of the entailed phenomena and the multi‐scale aspects to be taken into account, a river restoration project can be considered as a complex problem. Integrative approaches and modelling tools are thus needed to help river managers make predictions on the evolution of hydromorphological, socio‐economic, safety and ecological issues. Such approach can provide valuable information for handling long‐term management plans that consider the interaction and the balance of stakeholders interests and river system functioning. In this paper, we present a probabilistic participatory modelling (PM) method that assesses the effects of given restoration actions, knowing the hydromorphological modifications that they may induce on the safety, ecological and socio‐economic aspects with the help of local stakeholders through several workshops. To support this strategy, we used Bayesian networks (BNs) as modelling tools as their causal graphs can combine multidimensional knowledge and data from diverse natures. We introduce the causal graphs elaborated with the help of the stakeholders and convert it into BNs that can assist restoration decisions by considering the available decision and utility functions to provide guidance to decision‐makers. This was applied to the “Lac des Gaves” reach in the Hautes‐Pyrénées, France, a reach that has gone through severe sediment extractions for over 50 years. Each network represents possible restoration decisions linked to one of the observed issues. The paper demonstrates how BNs used as a decision support system (DSS) can help to assess the influence of given management strategies on the river system with the consideration of stakeholders’ knowledge and integration in all the modelling process. 相似文献
44.
Multimedia Tools and Applications - Currently we are facing a wide interest in multimedia security and copyright protection due to the explosion of data exchange in the Internet and the extensive... 相似文献
45.
Redouane Bouchekir Mohand Cherif Boukala 《Innovations in Systems and Software Engineering》2018,14(3):229-244
Many real-life critical systems are described with large models and exhibit both probabilistic and non-deterministic behaviour. Verification of such systems requires techniques to avoid the state space explosion problem. Symbolic model checking and compositional verification such as assume-guarantee reasoning are two promising techniques to overcome this barrier. In this paper, we propose a probabilistic symbolic compositional verification approach (PSCV) to verify probabilistic systems where each component is a Markov decision process (MDP). PSCV starts by encoding implicitly the system components using compact data structures. To establish the symbolic compositional verification process, we propose a sound and complete symbolic assume-guarantee reasoning rule. To attain completeness of the symbolic assume-guarantee reasoning rule, we propose to model assumptions using interval MDP. In addition, we give a symbolic MTBDD-learning algorithm to generate automatically the symbolic assumptions. Moreover, we propose to use causality to generate small counterexamples in order to refine the conjecture assumptions. Experimental results suggest promising outlooks for our probabilistic symbolic compositional approach. 相似文献
46.
Boufenneche Yassine Zitouni Rafik George Laurent Gharbi Nawel 《Wireless Networks》2021,27(6):3927-3946
Wireless Networks - Performance and communication security in the Internet of Things (IoT) area draw a major concern for both academic and industrial communities. Indeed, an emerging number of IoT... 相似文献
47.
Hossein Birjandi Nejad Mark A. Paczkowski Yassine Malajati R. Brian Melkowits 《应用聚合物科学杂志》2018,135(25)
A need exists for rheological modifiers that provide thickening for organic (oil) phases in the personal care industry. Despite such a significant need, most commercially available oil thickeners have several deficiencies, notably poor efficiency and clarity in formulations. To address this gap, we have developed a novel polyurethane‐based oil thickener (Oil‐Thickener PU) that provides significant thickening (gelation at <1 wt %) and high clarity in a range of natural oils and synthetic emollients. In this work, the structure, thickening mechanism, and viscoelastic properties of neat Oil‐Thickener PU film and Oil‐Thickener in sunflower oil gel are investigated in depth. Results show that the Oil‐Thickener PU provides thickening by forming a physically crosslinked network in oil via hydrogen bonding, resulting in a gel that is shear and temperature sensitive. Given its efficiency and uniqueness, the Oil‐Thickener PU is projected to have use in applications where a thickened organic phase is required. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46372. 相似文献
48.
Amal Al-Abri Yassine Jamoussi Naoufel Kraiem Zuhoor Al-Khanjari 《Telematics and Informatics》2017,34(6):878-893
There are a number of approaches to learning such as traditional approaches (teacher-centered) and collaborative approaches (learner-centered). Nowadays, the concepts of collaboration and social interactions are the major trends in education. Therefore, many researchers embrace these concepts to offer the educational field enhanced learning environments which are supported by communication and collaboration techniques. The adaptation causes the existence of varied approaches which are addressing the collaborative learning techniques. As a result, there is a need for a mechanism to study those approaches and highlight their eminence. The aim of this paper is to give a comprehensive overview about the state-of-art in collaborative learning, especially by integrating social media tools. To do so, the study adopts a classification framework based on four different views (subject, purpose, method, and tool). The framework has been used to compare ten collaborative e-learning approaches. The finding indicates the potential of all approaches in developing an online learning environment for remote collaborative learning despite the lack of fulfilling all the requirements highlighted in the four views. 相似文献
49.
Yassine Ennaciri Mohammed Bettach Hanan El Alaoui-Belghiti 《The International journal of environmental studies》2020,77(2):297-306
ABSTRACTThe production of phosphoric acid generates an enormous amount of phosphogypsum with emission of toxic fluorine acid gas. To remedy these environmental problems, a novel and a simple procedure permits converting phosphogypsum waste by recycled fluorine acid into valuable products. The obtained results confirm the efficiency of this procedure, which synthesises at room temperature the calcium fluoride in the form of nano-crystalline powder and the ammonium bisulphate salt from the exact stoichiometric proportions of phosphogypsum, hydrofluoric acid and ammonia. The total conversion of phosphogypsum is achieved after reaction time equal to one hour and a half. Generally, this novel procedure offers not only a solution for reducing phosphogypsum waste and fluorine gas emission, but also gives rise to valuable products, useful to industry and agriculture. 相似文献
50.
基于非线性稳定模型,推导出弯曲和轴向荷载作用下具有双向对称I型截面的简支梁柱构件的分析方案。设计中对一些具有代表性的荷载工况提供了一种独特紧凑的截面形式。分析中考虑了一阶弯曲分布,装载高度,预屈曲挠度效应和轴向荷载。通过采用壳单元的非线性有限元分析对建议的解决方案进行验证。所提议方法与非线性平衡方程计算结果能很好地吻合,证明古典线性稳定性的解决方案低估了这种构件在侧向屈曲稳定中的抵抗能力,尤其是大翼缘的I型截面。对轴力在超静定梁的抗侧向屈曲中所起作用进行数值研究,发现:当梁的轴向变形受到限制时会在梁中产生轴拉力作用,这导致了一些梁截面变形减小,梁呈现出无分叉的非线性性能。 相似文献