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Challenges in the Mining and Utilization of Deep Mineral Resources

Engineering 2017年第4期3卷 432-433页

作者： Meifeng Cai Edwin t. Brown Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology Beijing Beijing 100083 China Colder Associates Pty. Ltd. Brisbane QLD 4064 Australia the University of Queensland Brisbane OLD 4072 Australia

As Mote et al. [1] have noted in this journal, advances in the fields of engineering science and technology have played an indispensable role in shaping the social and economic development of humankind. However, the continuing development of science and technology, along with the world’s ever-growing population, is consuming the earth’s resources, including its mineral resources, at what may ultimately prove to be unsustainable rates. After hundreds of years of mining, the more accessible shallow mineral resources are being depleted, and some have now been completely exhausted. this means that the economic exploitation of more of the earth’s deeper mineral resources is now required in order to meet society’s growing demand for minerals. this demand is not only for the traditional metallic ores and energy sources, but also for minerals such as rare earths, which are being used at an increasing rate with the advent of new technologies in the fields of communication, power generation, and power storage, among others. the efficient mining and utilization of deep mineral resources is not one of the Grand Challenges for Engineering that were identified in recent years by the US National Academy of Engineering, the UK Royal Academy of Engineering, and the Chinese Academy of Engineering (CAE), as listed by Mote et al. [1]. However, it is clear that traditional and newer mineral resources will be required in order to develop solutions to most of the Grand Challenges that have been identified.Exploitable mineral resources exist at great depth in the form of a number of orebody types in a range of geological and geometrical settings. the current seven deepest mines in the world mine tabular or stratiform gold deposits in the Witwatersrand Basin of South Africa. the deepest of these mines are now around 4 km deep. the next deepest mines in the world are two base metal mines in Canada, which are about 3 km deep. For the purpose of this discussion, deep mining is taken to i

关键词： Mineral resources

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Design of a two-dimensional Recursive Filter Using the Bees Algorithm

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International journal of Automation and computing 2010年第3期7卷 399-402页

作者： D.t.Pham Ebubekir Koc Manufacturing Engineering Centre Cardiff University Cardiff CF24 3AA UK

this paper presents the first application of the bees algorithm to the optimisation of parameters of a two-dimensional （2D） recursive digital filter. the algorithm employs a search technique inspired by the foraging behaviour of honey bees. the results obtained show clear improvement compared to those produced by the widely adopted genetic algorithm （GA）.

关键词： Bees algorithm swarm intelligence optimisation two-dimensional digital filter design.

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A structural topological optimization method for multi-displacement constraints and any initial topology configuration

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Acta Mechanica Sinica 2010年第5期26卷 735-744页

作者： j. H. Rong j. H. Yi School of Automotive and Mechanical Engineering Changsha University of Science and TechnologyChangsha 410076 China

In density-based topological design, one expects that the final result consists of elements either black （solid material） or white （void）, without any grey areas. Moreover, one also expects that the optimal topology can be obtained by starting from any initial topology configuration. An improved structural topological optimization method for multidisplacement constraints is proposed in this paper. In the proposed method, the whole optimization process is divided into two optimization adjustment phases and a phase transferring step. Firstly, an optimization model is built to deal with the varied displacement limits, design space adjustments, and reasonable relations between the element stiffness matrix and mass and its element topology variable. Secondly, a procedure is proposed to solve the optimization problem formulated in the first optimization adjustment phase, by starting with a small design space and advancing to a larger deign space. the design space adjustments are automatic when the design domain needs expansions, in which the convergence of the proposed method will not be affected. the final topology obtained by the proposed procedure in the first optimization phase, can approach to the vicinity of the optimum topology. then, a heuristic algorithm is given to improve the efficiency and make the designed structural topology black/white in both the phase transferring step and the second optimization adjustment phase. And the optimum topology can finally be obtained by the second phase optimization adjustments. two examples are presented to show that the topologies obtained by the proposed method are of very good 0/1 design distribution property, and the computational efficiency is enhanced by reducing the element number of the design structural finite model during two optimization adjustment phases. And the examples also show that this method is robust and practicable.

关键词： topological optimization Displacement constraint Continuum structure Design space adjustment Rational approximation material model

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Introduction to the special column： communication, cooperation, and cognition in predators

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Current Zoology 2017年第3期63卷 295-299页

作者： Arik KERSHENBAUM Daniel t. BLUMStEN Department of Zoology University of Cambridge Cambridge CB23EJ UK Evolutionary Biology University of California Los Angeles CA 90095-1606 USADepartment of Ecology and

Communication is the glue that holds societies together and we might expect that highly social species with more to communicate about will have more complex communication systems and more complex cognitive abilities. Social species gain benefits from living in groups, and many of these benefits rely on intra-group communication. For example, predator-specific alarm calls can lead to different evasion responses (Suzuki 2014), or difficult to obtain food resources can be acquired using aggregation calls (King and janik 2015).

关键词：捕食者交流合作社会性认知能力通讯系统群体生活回避反应

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Design and Robust Performance Evaluation of a Fractional Order PID Controller Applied to a DC Motor

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IEEE/CAA journal of Automatica Sinica 2017年第2期4卷 304-314页

作者： j.Viola L.Angel j.M.Sebastian Universidad Pontificia Bolivariana Universidad Politecnica de Madrid Centre for Automation and Robotics (CAR) UPM-CSIC

this paper proposes a methodology for the quantitative robustness evaluation of PID controllers employed in a DC motor. the robustness analysis is performed employing a 2~3 factorial experimental design for a fractional order proportional integral and derivative controller(FOPID), integer order proportional integral and derivative controller(IOPID)and the Skogestad internal model control controller(SIMC). the factors assumed in experiment are the presence of random noise,external disturbances in the system input and variable load. As output variables, the experimental design employs the system step response and the controller action. Practical implementation of FOPID and IOPID controllers uses the MAtLAB stateflow toolbox and a NI data acquisition system. Results of the robustness analysis show that the FOPID controller has a better performance and robust stability against the experiment factors.

关键词： Factorial experimental design fractional-order PID controller robustness analysis SIMC PID controller

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towards a unified nonlocal, peridynamics framework for the coarse-graining of molecular dynamics data with fractures

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Applied Mathematics and Mechanics(English Edition) 2023年第7期44卷 1125-1150页

作者： H.Q.YOU X.XU Y.YU S.SILLING M.D'ELIA j.FOStER Department of Mathematics Lehigh UniversityBethlehemPA 18015U.S.A Department of Petroleum and Geosystems Engineering The University of Texas at AustinTX 78712-1139U.S.A. Center for Computing Research Sandia National LaboratoriesCA 94551-0969U.S.A.

Molecular dynamics(MD)has served as a powerful tool for designing materials with reduced reliance on laboratory ***,the use of MD directly to treat the deformation and failure of materials at the mesoscale is still largely beyond *** this work,we propose a learning framework to extract a peridynamics model as a mesoscale continuum surrogate from MD simulated material fracture data ***,we develop a novel coarse-graining method,to automatically handle the material fracture and its corresponding discontinuities in the MD displacement data *** by the weighted essentially non-oscillatory(WENO)scheme,the key idea lies at an adaptive procedure to automatically choose the locally smoothest stencil,then reconstruct the coarse-grained material displacement field as the piecewise smooth solutions containing ***,based on the coarse-grained MD data,a two-phase optimizationbased learning approach is proposed to infer the optimal peridynamics model with damage *** the first phase,we identify the optimal nonlocal kernel function from the data sets without material damage to capture the material stiffness ***,in the second phase,the material damage criterion is learnt as a smoothed step function from the data with *** a result,a peridynamics surrogate is *** a continuum model,our peridynamics surrogate model can be employed in further prediction tasks with different grid resolutions from training,and hence allows for substantial reductions in computational cost compared with *** illustrate the efficacy of the proposed approach with several numerical tests for the dynamic crack propagation problem in a single-layer *** tests show that the proposed data-driven model is robust and generalizable,in the sense that it is capable of modeling the initialization and growth of fractures under discretization and loading settings that are different from the ones used during training.

关键词： nonlocal model machine learning homogenization peridynamics material fracture

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Identification of a disulfide bonded protein from cytoplasm of Bacillus subtilis

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Chinese Science Bulletin 1997年第20期42卷 1756-1760页

作者： Wang, t Kadokura, H Yamasaki, M Chinese Acad Sci Inst Bot Beijing 100095 Peoples R China

DISULFIDE bonds are important for some proteins to form stable secondary or tertiary conforma-tion. these known disulfide bonded proteins are mainly present in periplasm or cel1ular or-ganelles, most of which are secreted proteins or membrane proteins. It is generally recog-nized that cytoplasmic proteins do not have disulfide bonds because of reducing environment

关键词： Bacillus subtilis cytoplasm disulfide bonded protein.

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Cataract blindness in Hungary

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International journal of Ophthalmology(English edition) 2020年第3期13卷 438-444页

作者： Gábor L.Sándor Gábor tóth Dorottya Szabó Irén Szalai Regina Lukács Anita Pék Georgina Z.tóth András Papp Zoltán Z.Nagy Hans Limburg jános Németh Department of Ophthalmology Semmelweis UniversityBudapest 1085Hungary Department of Ophthalmology Flór Ferenc HospitalKistarcsa 2143Hungary Department of Ophthalmology Petz Aladár HospitalGyor 9024Hungary Faculty of Health Sciences Semmelweis UniversityBudapest 1088Hungary Health Information Services Grootebroek 1613The Netherlands

AIM:to estimate the prevalence of blindness and visual impairment resulting from cataract in the population aged≥50 y in Hungary,and to assess the cataract surgical ***:A rapid assessment of avoidable blindness(RAAB)was conducted.A total of 3523 eligible people were randomly selected and *** participant underwent surgery for cataract was interviewed with regard to the year,place,and costs of the *** with obvious cataract were asked why they had not yet undergone surgery(barriers to surgery).RESULtS:An estimated 12514 people were bilaterally blind;the visual acuity(VA)in 19293 people wasthe VA in 73962 people wasthe better eye due to *** estimated 77933 eyes are blind;98067 eyes had a VA oftimated 277493 eyes had a VA ofto *** all cataract surgeries were conducted in government *** age-and sexadjusted cataract surgical coverage with VAthe rate of good visual outcome after surgery was 79.5%.Ocular comorbidity was the main cause of poor outcome(78.1%),followed by late complications(such as posterior capsule opacification)(17.2%),inadequate optical correction(3.1%),and surgical complications(1.6%).the main barrier to surgery in people with bilateral cataract and VA oft felt’.CONCLUSION:the prevalence of visual impairment resulting from cataract is slightly higher than *** quality of the cataract surgical service seems adequate in ***,the number of cataract operations per year should continue to increase due to the increasing patient demands and the aging population.

关键词： cataract prevalence blindness visual impairment rapid assessment of avoidable blindness

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Analgesic and anti-inflammatory activities of Passiflora foetida L.

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Asian Pacific journal of tropical Medicine 2011年第8期4卷 600-603页

作者： Sasikala V Saravanan S Parimelazhagan t Bioprospecting Laboratory Department of BotanyBharathiar UniversityCoimbatoreTamil NaduIndia

Objective:to investigate the analgesic and anti-inflammatory activities of ethanol extract of Passiflora foetida(***) ***:Ethanol extract of *** leaf was evaluated for analgesic action by acetic acid-induced writhing and hot plate method in albino *** anti-inflammatory property of ethanolic leaf extract was tested by carrageenan induced acute paw edema and histamine induced acute paw edema in ***:the dose 200 mg/kg of P. foetida leaf extract exhibited highest significant analgesic activity[(13.50±0.43) min]at a reaction time of 20 min in hot plate method in *** ethanol extract of leaf dose 100 mg/kg produced a highly significant anti inflammatory effect[(1.302±0.079) mL]in ***:It is very clear that *** also has analgesic and anti-inflammatory activities for the pharmaceuticals.

关键词： Passiflora foetida Carrageenan Histamine Analgesic Anti-inflammatory

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Integrated procedure for shape and topology optimization of shell structures

Integrated procedure for shape and topology optimization of ...

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the Fourth World Congress of Structural and Multidisciplinary Optimization

作者： R.Ansola j.Canales j.A.tárrago j.Rasmussen Departamento de Ingeniería Mecánica.Escuela Superior de Ingenieros de Bilbao UPV/EHU.Alda.Urquijo s/n 48013 BilbaoSpain Departamento de Ingeniería Mecánica.Escuela Superior de Ingenieros de Bilbao UPV/EHU.Alda.Urquijo s/n 48013 BilbaoSpain Departamento de Ingeniería Mecánica.Escuela Superior de Ingenieros de Bilbao UPV/EHU.Alda.Urquijo s/n 48013 BilbaoSpain Institute of Mechanical *** University.Pontoppidanstraede 101 DK-9220 AalborgDenmark

＜正＞the global scope of this work is to develop an integrated shape and topology optimization system for the optimum design of shell structures, which are now finding widespread use in aeronautical, automotive, civil and mechanical engineering. the proposed investigation project aims to progress on a brand new work line which has captured the mind of many researchers: the shape and topology optimization for "Computer Aided Optimal Design" [1]. this project is based on the combination of shape and topology optimization techniques, with the aim of finding the optimal shape and material distribution that maximizes the stiffness of the shell. Most research in the last decades considered both optimization techniques separately, seeking an initial optimal topology and refining the shape of the solution later [2]. the method implemented in this work uses a combined approach, were the shape of the shell structure and material distribution are optimized simultaneously. this formulation involves a variable ground structure for topology optimization, since the shape of the shell is modified in the course of the process. the presented method will enhance the exploration of better designs for carrying the applied loads, due to the ability of optimizing not only the shape of the structure, but also the material distribution over the shell. this technique would provide the designer with a tool which would help to conceive the best configuration of the element considered in each situation. the method has been implemented into a general optimization software called ODESSY, developed at the Institute of Mechanical Engineering in Aalborg. the computational model was successfully tested in several numerical applications to illustrate and validate the approach, discussing the efficiency and feasibility of the method.

关键词： Shell structure optimization topology homogenization.

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