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Boosted on-chip energy storage with transistors

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National Science Review 2022年第10期9卷 56-57页

作者： Tongchao Liu Khalil amine Chemical Sciences and Engineering Division Argonne National Laboratory Materials Science and Engineering Stanford University

On-chip energy-storage devices play an important role in powering wireless environmental sensors and microelectrome chanical systems [1,2].Starting from the 1980s,on-chip energy-storage devices,including microbatteries and super capacitors,have been applied to power the real-time clock on a chip [3].These tiny batteries/supercapacitors enable the real-time clock to keep working when the electronics are *** this way,electronic devices can be restarted with a valid *** the development of electronic devices,signal processing and communication have become much faster,while also requiring more powerful energy-storage devices to drive them [4-6].

关键词： high-temperature superconductivity oxygen doping electric field effect all-solid-state field effect transistor superconductor–insulator transition

Mechanical Characterisation of Interface for Steel/Polymer Composite Using Pull-out Test: Shear-Lag and Frictional Analysis

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Journal of Materials Science & Technology 2006年第4期22卷 552-558页

作者： Mohamed KHARRAT Maher DAMMAK amine CHARFI Institut Préparatoire aux Etudes d'Ingénieurs de Sfax Tunisia Laboratoire des Systèmes ElectromécaniquesEcole Nationale d'Ingénieurs de SfaxTunisia Laboratoire des Systèmes Electromécaniques Ecole Nationale d'Ingénieurs de SfaxTunisia

Fibre-matrix interface is known to have contribution to the mechanical performance of fibre-reinforced composite by its potential for load transfer between the fibre and the matrix. Such load transfer is of great importance in dentistry when a post is used for fixing a ceramic crown on the tooth. In this study, a pull-out test was carried out to analyse the interfacial properties of a steel fibre embedded in a polyester and epoxy matrices. It was found that the fibre-matrix interface is debonded on the whole embedded length when the fibre stress reached the debonding stress. Then, the fibre stress fell down to the initial extraction stress required to pulling out the debonded fibre from the matrix. Both debonding stress and initial extraction stress initiated a linear increase with the implantation length after the debonding stress reached horizontal asymptotes. To analyse the fibre-matrix load transfer before debonding, an analytical shear-lag model was adopted to in this test conditions. Fitting the experimental results with the analytical model provided the interfacial shear strength. By considering the Coulomb friction at the fibre-matrix interface during the fibre extraction process, an analytical model which considers Poisson＇s effects on both fibre and matrix, was developed. In this model, knowledge of the initial extraction stress of the fibre provides the residual normal stress at the fibre-matrix interface.

关键词： Fibre Matrix Interface Pull-out Shear-lag Debonding Friction

Numerical investigation of the stresses in backfilled stopes overlying a sill mat

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第3期9卷 108-119页

作者： Mohamed amine Sobhi Li Li Research Institute on Mines and the Environment Department of Civil Geological and Mining Engineering école Polytechnique de Montréal MontréalCanada

Backfill is commonly used in underground mines to help increase the ore recovery rate and reduce the ore dilution. The use of a part of mine waste as underground backfill material also helps reduce the environmental impact of mining operations. After all, backfill is used to provide a working platform or safer working space. Its primary and most important role is to improve the rock mass stability around mine openings. However, most available solutions to stress analyses were developed for an isolated stope, without taking into account the influence of mine depth, or of adjacent stopes. In this paper,results from a numerical study carried out to evaluate the stresses in backfilled stopes overlying a sill mat are presented. Mine depth and excavation of the underlying stope below the sill mat(horizontal pillar)are both taken into consideration. The influence of stope geometry, backfill, sill mat and rock properties on the stresses is also evaluated. Compared with the case of a single isolated backfilled stope, the numerical results show that the stress magnitudes in the overlying backfill are considerably increased due to the excavation of the underlying stope. In general, the stresses also increase with mine depth and backfill stiffness, while these tend to decrease with an increase in the surrounding rock mass *** results suggest that existing solutions for backfill design may need to be revised.

关键词： Mine depth Backfill Sill mat Stresses Numerical modeling

On the Optimal Design of Cable Driven Parallel Robot with a Prescribed Workspace for Upper Limb Rehabilitation Tasks

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Journal of Bionic Engineering 2019年第3期16卷 503-513页

作者： Laribi Med amine Carbone Giuseppe Zeghloul Said Department of GMSC Pprime Institute CNRS-University of Poitiers - ENSMA - UPR 3346 Poitiers France Department of Mechanical Energy and Management Engineering University of Calabria 87036 Rende Italy CESTER Technical University of Cluj-Napoca Muncii Ave. 103-105 400641 Cluj-Napoca Romania

This paper deals with an optimization approach to design a cable driven parallel robot intended for upper limb rehabilitation tasks. The cable driven parallel robots have characteristics that make them best candidate for rehabilitation exercise purposes such as large workspace, re-configurable architecture, portability and cost effectiveness. Here, both the cable tensions that are needed to move a wristband as well as the workspace need to be carefully optimized for fulfilling the prescribed operation tasks. A specific case of study is addressed in this work by referring to LA RM wire driven exercising device (LAWEX), which is applied to upper limbs exercises. To that end, a motion capture system is used to collect quantitative data on the prescribed workspace of a human upper limb. A specific optimization problem is settled up for considering combining two optimization goals, namely, the smallest robot size reaching a prescribed workspace and the minimum cable tension distributions. A sequence of optimization steps is defined using Genetic Algorithms (GAs) applied to LAWEX robot. The proposed objective function is based on a mathematical formulation of the power of a point with respect to bounding surfaces in combination with a performance index to show the distributions of the minimum cable tensions.

关键词： LAWEX robot design bionic robot cable-driven robots optimization power of the point rehabilitation tasks

Endoscopic retrieval of gastric trichobezoar after fragmentation with electrocautery using polypectomy snare and argon plasma coagulation in a pediatric patient

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Gastroenterology Report 2016年第3期4卷 251-253,I0003页

作者： Mohammed amine Benatta Digestive Endoscopy Unit Military Central HospitalAlgiersAlgeria

Trichobezoars are rare,composed of hair and more common in female pediatric patients with psychiatric *** extraction is the most common removal *** two endoscopic removals after fragmentation have beenreported in the English *** report herein a third case of a trichobezoar that was successfully retrieved afterendoscopic fragmentation with snare polypectomy and argon plasma coagulation in a six-year-old female *** mass was completely removed in 10 pieces after 15 *** patient’s course was *** monthslater,she is doing *** endoscopic removal was effective,minimally invasive and time saving.

关键词： trichobezoar retrieval endoscopic fragmentation

Suppressing the Impedance Rise of LiNi_(0.8)Co_(0.2)O_2/Graphite Cells by Al, Ti and Mg Doping

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过程工程学报 2004年第1期4卷 59-63页

作者：陈春华谢松柳俊 amine K Dept. Mat. Sci.& Eng. University of Science and Technology of China Hefei Anhui 230026 China Electrochem. Technol. Progy. Chem. Technol. Div. ANL. Argonne Illinois 60439 USA

The research on utilizing lithium-ion batteries with LiNi0.8Co0.2O2-based cathode for hybrid electric vehicles is intensively underway in several national laboratories of US Department of Energy. The impedance of LiNi0.8Co0.2O2/graphite lithium-ion cells is observed to experience a substantial rise during accelerated calendar life storage, due mainly to the significant increase of the interfacial resistance on the cathode side. By means of electrochemical measurements and AC impedance spectroscopy, it is found that doping the LiNi0.8Co0.2O2 cathode with small amount of Al, Ti and Mg can effectively suppress this impedance rise. Possible mitigation of oxidizing ability of Ni4+ due to Al, Ti and Mg doping is proposed to achieve this impedance stabilization.

关键词：掺杂铝钛镁电池电极阻抗

Analysis and optimal synthesis of single loop spatial mechanisms

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第9期12卷 665-679页

作者： Med amine LARIBI Lotfi ROMDHANE Sad ZEGHLOUL Laboratoire de Génie Mécanique LAB-MA-05 Ecole Nationale d'Ingénieurs de Sousse Institut Pprime-UPR 3346 CNRS-Université de Poitiers-ENSMA Département Génie Mécanique et Systémes Complexes SP2MIBP30179 86962 Futuroscope France

In this work, a systematic approach is presented to obtain the input-output equations of a single loop 4-bar spatial mechanisms. The dialytic method along with Denavit-Hartenberg parameters can be used to obtain these equations efficiently. A genetic algorithm （GA） has been used to solve the problem of spatial mechanisms synthesis. Two types of mechanisms, e.g., RSCR and RSPC （R： revolute; S： spherical; C： cylindrical; P： prismatic）, have illustrated the application of the GA to solve the problem of function generation and path generation. In some cases, the GA method becomes trapped in a local minimum. A combined GA-fuzzy logic （GA-FL） method is then used to improve the final result. The results show that GAs, combined with an adequate description of the mechanism, are well suited for spatial mechanism synthesis problems and have neither difficulties inherent to the choice of the initial feasible guess, nor a problem of convergence, as it is the case for deterministic methods.

关键词： Spatial mechanisms Genetic algorithm-fuzzy logic (GA-FL) method Denevit-Hartenberg parameters Mechanism synthesis

Dependency-aware unequal erasure protection codes

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第z1期7卷 27-33页

作者： BOUABDALLAH amine LACAN Jérme Laboratory for Analysis and Architecture of Systems Toulouse 31077 France Applied Mathematics and Computer Science DepartmentENSICAToulouse 31056France Telecommunications for Space and AeronauticToulouse 31000France

Classical unequal erasure protection schemes split data to be protected into classes which are encoded independently. The unequal protection scheme presented in this paper is based on an erasure code which encodes all the data together according to the existing dependencies. A simple algorithm generates dynamically the generator matrix of the erasure code according to the packets streams structure, i.e., the dependencies between the packets, and the rate of the code. This proposed erasure code was applied to a packetized MPEG4 stream transmitted over a packet erasure channel and compared with other classical protection schemes in terms of PSNR and MOS. It is shown that the proposed code allows keeping a high video quality-level in a larger packet loss rate range than the other protection schemes.

关键词： Data dependencies integration Unequal erasure protection (UEP) Lossy networks Reliable video transmissions MPEG4 video codec

Influence of Discretization Step on Asymptotic Stability of a Certain Class of Two-dimensional Continuous-discrete Fractional Linear Systems

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Acta Mathematicae Applicatae Sinica 2022年第1期38卷 68-77页

作者： Souad BOUGUESSA Djillali BOUAGADA Mohammed amine GHEZZAR Department of Mathematics and Computer Science ACSY Team-Laboratory of Pure and Applied Mathe-maticsAbdelhamid Ibn Badis University MostaganemP.O.Box 227/118University of Mostaganem27000 MostaganemAlgeria

The effectiveness of this paper lies in the influence of the discretization step on the asymptotic stability of the positive two-dimensional fractional linear *** aims at investigating whether,how and when this step affects the asymptotically stable two-dimensional positive fractional linear continuous-discrete *** accomplish this study,a new test was outlined and used so that the asymptotic stability of the system was measured both before and after being exposed to the sampling ***,the conditions of that stability were *** a result,the outcome of the approximation shows that the stability is preserved under a particular set of *** this basis,the newly proposed approach is recommended for testing the intended stability of such systems.A numerical example is tested to show the accuracy and the applicability of the proposed tests.

关键词： discretization positivity stability two-dimensional systems