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Theoretical bounds on Fresnel compressive holography performance(Invited Paper)

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Chinese Optics Letters 2014年第6期12卷 99-102页

作者： Adrian Stern Yair Rivenson department of Electro-Optics engineering Ben-Gurion University of the NegevBeer-Sheva 84105 Israel Faculty of engineering Bar-Ilan University5290 Ramat-Gan Israel

During the last years the theory of compressive sensing has found significant utility in the digital holography realm. In this letter we summarize and extend our previous theoretical results which determine the relation between the number of Fresnel samples required on the object illumination type, illumination wavelength, imaging geometry and sensor＇s size and resolution.

关键词： Theoretical bounds on Fresnel compressive holography performance

Performance evaluation of waste electrical and electronic equipment disassembly layout configurations using simulation

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Frontiers of Environmental Science & engineering 2017年第5期11卷 65-75页

作者： Ozan Capraz Olcay Polat Askiner Gungor department of industrial engineering Naxmk Kemal University Corlu/Tekirdag 59860 Turkey department of industrial engineering Pamukkale University Pamukkale/Denizli 20160 Turkey

Recycling of waste electrical and electronic equipment （WEEE） is crucially important since it handles hazardous waste according to ever tightening laws and regulations and it adds benefits to economy and sustainable environment. Disassembly is one of the most important processes performed during the recovery of WEEE. The overall goal of disassembly is to maximize the retrieval of various metals and plastics contained in WEEE in order to reduce their negative effects on human health and environmental sustainability and to increase economic gains. This study aims to evaluate alternative layout configurations for WEEE disassembly systems （WDS）. In this context, various configurations were compared in terms of pre-defined performance criteria, such as the total number of disassembled WEEE and the total revenue from sales, using simulation models. The results of this study show that the perfomaance of a WDS was significantly affected by output transfer systems along with the specialization of operators on certain types of WEEE.

关键词： WEEE Recovery Disassembly Layout planning Simulation

On the Atomic Kinetic Energies in Ceramic Oxides

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Journal of Materials Science and Chemical engineering 2017年第12期5卷 17-27页

作者： Yacov Finkelstein Raymond Moreh Rony Shneck Chemistry Division Nuclear Research Center-Negev Beer-Sheva Israel department of Physics Ben-Gurion University of the Negev Beer-Sheva Israel department of Materials and engineering Ben-Gurion University of the Negev Beer-Sheva Israel

We calculated the mean atomic kinetic energy, , of the X atom (X = Si, Ti, Hf, O) in some ceramic oxides, SiO2, TiO2 and HfO2 using the published partial vibrational density of states (PVDOS). These were simulated by means of lattice dynamics, molecular dynamics and density functional theory. The predicted values are compared to those recently obtained by electron Compton scattering (ECS), with an overall good agreement of ~4%. In accord with calculations, the ECS measurements reveal a small, but detectable, dependence of on the fine structural details of the oxide, e.g. whether it is in a crystalline or amorphous form, and whether it exhibits surface or bulk characteristics. This study illustrates the limitations and the potential of PVDOS simulations in predicting experimental atomic kinetic energies, and can be viewed as a promising approach for elucidating valuable structural and dynamical information of ceramic oxides and other materials.

关键词： Ceramic Oxides Atomic Kinetic Energy Vibrational Density of States Electron Compton Scattering

Performance Analysis of Intelligent Robust Facility Layout Design

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Chinese Journal of Mechanical engineering 2017年第2期30卷 407-418页

作者： G MOSLEMIPOUR T S LEE Y T LOONG department of industrial engineering Payame Noor University Faculty of engineering and Technology Multimedia University

Design of a robust production facility layout with minimum handling cost （MHC） presents an appropriate approach to tackle facility layout problems in a dynamic volatile environment, in which product demands randomly change in each planning period. The objective of the design is to find the robust facility layout with minimum total material handling cost over the entire multiperiod planning horizon. This paper proposes a new mathematical model for designing robust machine layout in the stochastic dynamic environment of manufacturing systems using quadratic assignment problem （QAP） formulation. In this investigation, product demands are assumed to be normally distributed random variables with known expected value, variance, and covariance that randomly change from period to period. The proposed model was verified and validated using randomly generated numerical data and benchmark examples. The effect of dependent product demands and varying interest rate on the total cost function of the proposed model has also been investigated. Sensitivity analysis on the proposed model has been performed. Dynamic programming and simulated annealing optimization algorithms were used in solving the modeled example problems.

关键词： Robust layout Dynamic stochastic environment Manufacturing system Dynamic programming

Accelerated proportional degradation hazards-odds model in accelerated degradation test

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Journal of Systems engineering and Electronics 2015年第2期26卷 397-406页

作者： Tingting Huang Zhizhong Li School of Reliability and Systems engineering Beihang University department of industrial engineering Tsinghua University

An accelerated proportional degradation hazards-odds model is proposed. It is a non-parametric model and thus has path- free and distribution-free properties, avoiding the errors caused by faulty assumptions of degradation paths or distribution of degra- dation measurements. It is established based on a link function which combines the degradation cumulative hazard rate function and the degradation odds function through a transformation pa- rameter, and this makes the accelerated proportional degradation hazards model and the accelerated proportional degradation odds model special cases of it. Hypothesis tests are discussed, and the proposed model is applicable when some model assumptions are satisfied. This model is utilized to estimate the reliability of minia- ture bulbs under low stress levels based on the degradation data obtained under high stress levels to validate the effectiveness of this model.

关键词： accelerated proportional degradation hazards(APDH) accelerated proportional degradation odds(APDO) link function non-parametric

MAINTENANCE OF MULTI-STATE PRODUCTION SYSTEMS DETERIORATED BY RANDOM SHOCKS AND PRODUCTION

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Journal of Systems Science and Systems engineering 2011年第1期20卷 110-118页

作者： Won Seok YANG Dae E.LIM Kyung C.CHAE department of Business Administration Hannam University department of industrial and Systems engineering

We consider the preventive maintenance of a production system that is deteriorated by random shocks and the production process itself. The degree of deterioration is modeled by discrete and finite states. Shocks arrive according to a Poisson process and deteriorate the system by random amounts. The system may deteriorate whenever it produces an item. The system is continuously monitored and repaired if the system state is at or above a predetermined level for maintenance. We analyze the lifetime, product quantity, average cost, and average profit considering revenue from the product and cost due to setup, operation, and repair. Assuming a structure of system parameters and costs, using numerical examples, we investigate the impact of production and shock arrivals on the average profit and the optimal maintenance level that maximizes the average profit. The proposed model is applicable to manufacturing tasks in which machines wear due to production, for example, press processes, milling, turning, punching, and drilling.

关键词： Multi-state deterioration random shock maintenance cost-benefit analysis

Catalysts for the hydrogen evolution reaction in alkaline medium:Configuring a cooperative mechanism at the Ag-Ag_(2)S-MoS_(2) interface

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Journal of Energy Chemistry 2022年第11期31卷 481-488,I0013页

作者： Avraham Bar-Hen Simon Hettler Ashwin Ramasubramaniam Raul Arenal Ronen Bar-Ziv Maya Bar Sadan department of Chemistry Ben-Gurion University of the NegevBeer-Sheva 8410501Israel department of Chemistry Nuclear Research Center NegevP.O.Box 9001Beer-Sheva 84190Israel Laboratorio de Microscopías Avanzadas Universidad de Zaragoza50018 ZaragozaSpain Instituto de Nanociencia y Materiales de Aragon CSIC-U.de ZaragozaCalle Pedro Cerbuna 1250009 ZaragozaSpain department of Mechanical and industrial engineering University of MassachusettsAmherstMA 01003United States ARAID Foundation 50018 ZaragozaSpain

Designing electrocatalysts for HER in alkaline conditions to overcome the sluggish kinetics associated with the additional water dissociation step is a recognized challenge in promoting the hydrogen *** this end,delicately tuning the atomic-scale structure and surface composition of nanoparticles is a common strategy and,specifically,making use of hybrid structures,can produce synergistic effects that lead to highly active ***,we present a core-shell catalyst of Ag@MoS_(2)that shows promising results towards the hydrogen evolution reaction(HER)in both 0.5 M H_(2)SO_(4)and 0.5 M *** this hybrid structure,the MoS_(2)shell is strained and defective,and charge transfer occurs between the conductive core and the shell,contributing to the electrocatalytic *** shelling process results in a large fraction of Ag_(2)S in the cores,and adjusting the relative fractions of Ag,Ag_(2)S,and MoS_(2)leads to improved catalytic activity and fast charge-transfer *** suggest that the enhancement of alkaline HER is associated with a cooperative effect of the interfaces,where the Ag(Ⅰ)sites in Ag_(2)S drive the water dissociation step,and the formed hydrogen subsequently recombines on the defective MoS_(2)*** study demonstrates the benefits of hybrid structures as functional nanomaterials and provides a scheme to activate MoS_(2)for HER in alkaline conditions.

关键词： Water splitting Core-shell Catalytic mechanism Electrocatalysis 2D materials

A new method for the fast simulation of models of highly dependable Markov system

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Science China(Technological Sciences) 2005年第1期48卷 23-30页

作者： XIAO Gang LI Zhizhong department of industrial engineering Tsinghua University Beijing 100084 China Department of Industrial Engineering Tsinghua University Beijing 100084 China

To fast evaluate the small probability that starts from the all-components-up state, the system hits the failed sets before returning to the all-components-up state, Important Sampling or Important Splitting is used commonly. In this paper, a new approach distinguished from Important Sampling and Important Splitting is presented to estimate this small probability of highly dependable Markov system. This new approach achieves variance reduction through improving the estimator itself. The new estimator is derived from the integral equation describing the state transitions of Markov system. That the variance of this estimator is less than that of naive simulation at all time is proved theoretically. Two example involved reliability models with deferred repair are used to compare the methods of RB, IGBS, SB-RBS, naive simulation, and the method presented in this paper. Results show our method has the least RE.

关键词： statistical estimator, variance reduction, dependability measures, Markov system, integral equation.

Characterization of machine tools and measurement system for micromilling

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Nanotechnology and Precision engineering 2019年第1期2卷 23-28页

作者： Andrea Abeni Matteo Lancini Aldo Attansio department of Mechanical and industrial engineering University of Brescia

Technological progress has led to increased demand for small components with tiny features, which cannot be achieved through conventional machining. industrial application of processes based on microcutting is limited by some issues concerning the geometrical scale. The process performance is significantly affected by milling machine, tool holder, tool, workpiece material microstructure, workpiece fixtures, and process parameters. At present, an ultimate micromachining assessment procedure is not available. This study aims to propose and conduct an experiment on a testing procedure for micromilling. The set up to be implemented and the output to be considered are defined and described. Three major stages are identified: estimation of the effective bandwidth of the load cell–tool holder system, the milling machine natural frequency measurement, and micromilling test execution. The entire procedure is performed, and its robustness is demonstrated.

关键词： Micromilling Machine tool performance test Tool run-out Force analysis Modal analysis