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51.
52.
Khan Abdul Manan Yun Deok-won Zuhaib Khalil Muhammad Iqbal Junaid Yan Rui-Jun Khan Fatima Han Changsoo 《International Journal of Control, Automation and Systems》2017,15(2):802-814
International Journal of Control, Automation and Systems - In this paper, we have addressed two issues for upper limb assist exoskeleton. 1) Estimation of Desired Motion Intention (DMI); 2) Robust... 相似文献
53.
In light of current calls by medical professionals to confront the global issue of obesity and related illnesses, we developed a mobile application called STEP UP that monitors physical activity and provides data that can be easily shared within a social network. We then conducted an exploratory, theoretical study based on the theory of reasoned action (TRA) followed by an experimental trial and user study. The purpose of the studies was to explore the effect of persuasive technology on physical activity behavior and to investigate its effectiveness in motivating users to use the technology to be more physically active. The application was found to have a positive effect on the participants and their level of physical activity. They enjoyed using the application and were motivated to walk more, especially when enabled to share their step counts with their friends. The social component of the application clearly enhanced users’ walking experience, as the atmosphere of friendly competition motivated them to walk more. Based on user responses, we conclude that a further enhanced application that includes chat functionality may be even more successful in supporting increased physical activity and thus healthier lifestyle. 相似文献
54.
Khaled Safi Samer Mohammed Inke Marie Albertsen Eric Delechelle Yacine Amirat Mohamad Khalil Jean-Michel Gracies Emilie Hutin 《Signal, Image and Video Processing》2017,11(6):1081-1088
The present study proposes a new approach for the assessment of the human balance control. This approach is based on the decomposition of the center of pressure displacement using empirical mode decomposition (EMD) that provides an effective time-frequency analysis of non-stationary signals. Twenty-eight healthy subjects performed quiet standing in four conditions—feet apart/together with respect to eyes open/closed—while recording the stabilometric signals in the anteroposterior (AP) and mediolateral (ML) directions. The EMD method decomposes each stabilometric signal into several subsignals called intrinsic mode functions (IMFs). Stabilogram-diffusion analysis technique is applied to generate the diffusion curve of each IMF signal. Each diffusion curve is modeled as a second-order system and provides representative features, such as the gain parameter. Analysis of the gain parameter shows the major effect of visual input and feet conditions on the strategy to control/stabilize the balance. Significant differences were found between young and elderly, and between women and men. In addition, the impact of feet position seems to be higher in ML direction than in AP direction. 相似文献
55.
56.
Rejane Martins Fernandes Canha Kenneth de Borja Jaguaribe Ana Lúcia Homce de Cresce El Debs Mounir Khalil El Debs 《Engineering Structures》2009,31(3):788-798
This paper presents a theoretical and experimental analysis of socket base connections of precast concrete structures with regard to the behavior of transverse walls. The experimental program included seven specimens, for which the type of interface in contact with cast-in-place concrete, the load eccentricities and the embedded lengths were all varied. A design model was proposed to calculate the reinforcements of the transverse walls. Based on the obtained results, some conclusions can be drawn: (a) The top of the transverse wall on the compression side of the smooth connections and the top of the two transverse walls of the rough connections are submitted to a bending-tension and this tension prevails on the bending; (b) The design model proposed for the calculation of the reinforcement of the transverse wall on the compression side provides the best prediction of the experimental results for all specimens when compared to the current design models; (c) For rough interfaces, the top of the transverse wall on the tension side is more requested than the top of transverse wall on the compression side; (d) The results of the proposed design model for the reinforcement of the transverse wall on the tension side of rough connections were in close agreement with the experimental results. 相似文献
57.
Khalil Parvaneh Reza Haghbakhsh Alireza Shariati Cor J. Peters 《American Institute of Chemical Engineers》2015,61(9):3094-3103
A new model, named the crossover‐UNIQUAC model, has been proposed based on the crossover procedure for predicting constant‐pressure liquid–liquid equilibria (LLE). In this manner, critical fluctuations were incorporated into the classical UNIQUAC equation. Coexistence curves were estimated for systems having a diverse range of asymmetries. These systems included the LLE of five different mixtures, composed of nitrobenzene with one of the members of the alkane homologous family (either pentane, octane, decane, dodecane, or tetradecane), as well as an extra system having a different chemical nature, namely the mixture of n‐perfluorohexane and hexane, to further check the validity of the proposed approach. Using these nonideal mixtures, the validity of the new model was investigated within wide ranges, covering near‐critical to regions falling far away from the critical point. The graphical trends, as well as the quantitative comparison with experimental data indicated the good agreement of the proposed model results with the experimental data. A maximum AARD% value of 3.97% was obtained in calculating molar compositions by the proposed model for such challenging systems covering noncritical, as well as critical regions. In addition, to show the strength of the proposed crossover approach to describe properties other than LLE, molar heat capacities were investigated for the system of nitrobenzene + dodecane. © 2015 American Institute of Chemical Engineers AIChE J, 61: 3094–3103, 2015 相似文献
58.
Production of lipid from depolymerised lignocellulose using the biocontrol yeast,Rhodotorula minuta: The fatty acid profile remains stable irrespective of environmental conditions
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59.
T. K. K. Khalil U. Müller G. Ondracekd
《Materialwissenschaft und Werkstofftechnik》1996,27(5):227-238
Bioinert implant ceramics Part III. The powder-technological densification of nanoscaled ultra-fine powders of the Al2O3-SiO2-TiO2-system The characterization and densification of different nanoscaled power compositions out of the Al2O3-SiO2-TiO2-system is described, which have been produced by the hydrolysis- and/or sol-gel-method. Beside their chemical composition their morphology, specific surfaces and densities before and after pressure application as well as sintering are measured and the effect of drying and calcination is investigated separately. The results provide clearly
- that drying parameters do not have any relevant influence on densification
- that calcination at 1273 K/3 h leads to agglomerated powders free of humid constituents
- that the specific surfaces of the powders as well as their density decrease with increasing SiO2-content and increase with increasing Al2O3- and TiO2-content
- that agglomeration does not disadvantageously effect the densification, but that favorized concentration regions exist which provide high-dense, crack-free sintered pellets.
60.
Piero Portincasa Leonilde Bonfrate Mirco Vacca Maria De Angelis Ilaria Farella Elisa Lanza Mohamad Khalil David Q.-H. Wang Markus Sperandio Agostino Di Ciaula 《International journal of molecular sciences》2022,23(3)
Gut microbiota encompasses a wide variety of commensal microorganisms consisting of trillions of bacteria, fungi, and viruses. This microbial population coexists in symbiosis with the host, and related metabolites have profound effects on human health. In this respect, gut microbiota plays a pivotal role in the regulation of metabolic, endocrine, and immune functions. Bacterial metabolites include the short chain fatty acids (SCFAs) acetate (C2), propionate (C3), and butyrate (C4), which are the most abundant SCFAs in the human body and the most abundant anions in the colon. SCFAs are made from fermentation of dietary fiber and resistant starch in the gut. They modulate several metabolic pathways and are involved in obesity, insulin resistance, and type 2 diabetes. Thus, diet might influence gut microbiota composition and activity, SCFAs production, and metabolic effects. In this narrative review, we discuss the relevant research focusing on the relationship between gut microbiota, SCFAs, and glucose metabolism. 相似文献