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Forecasting vulnerability of deep extraction level excavations to drawinduced cave loads

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第3期11卷 527-534页

作者： matthew E.Pierce Pierce Engineering

Block and panel caving methods are increasingly used for mining of large and strong orebodies at large depths below the ground surface (>1 km). This paper focuses on the production phase of caving when the extraction level is fully developed and subjected to the weight of overlying caved material. A limit equilibrium solution for estimation of cave loads is critically reviewed and combined with existing empirical tools in order to forecast extraction level performance under cave loading. The analysis results, presented in nomogram form, suggest that the risk of severe squeezing of extraction level tunnels does not increase with cave depths below 500-1000 m due to the beneficial effects of arching. Under normal extraction ratios (ER = ~50%), severe squeezing experienced from cave loads in deep mines appears to be unlikely in all but the weakest rock masses (σcm < 5 MPa, where σcm is the rock mass global strength), even with poor draw control or low drawpoint availability. The likelihood of severe squeezing is greater when large draw areas (HR = 50-75 m, where HR is the hydraulic radius) are combined with low drawpoint availability or poor draw control and locally higher extraction ratios (ER = ~75%), even in better quality rock (σcm = 5-10 MPa). The analysis results are back-analyzed with the extraction level performance before and after a doubling production of rate and draw area at the deep ore zone (DOZ) mine in Indonesia. The extraction level conditions predicted by the nomograms correlate well with the experience at the DOZ, in which extraction level damage increases significantly over the production rampup, accompanied by a significant drop in drawpoint availability.

关键词： Block caving Panel caving Extraction level Draw control Squeezing

The importance of being connected:membrane contact sites and Parkinson’s disease

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Neural Regeneration Research 2023年第10期18卷 2202-2203页

作者： matthew E.Gegg Department of Clinical and Movement Neurosciences UCL Queen Square Institute of NeurologyLondonUK

Membrane contact sites (MCS) occur between closely apposed organelles and are a means to transport ions and macromolecules between themselves,co-ordinate cellular metabolism,and direct organelle fission and *** MCS be... 详细信息

关键词： connected transport ordinate

Phenotypic trait matching predicts the topology of an insular plant–bird pollination network

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Integrative Zoology 2018年第3期13卷 339-347页

作者： matthew BIDDICK Kevin CBURNS School of Biological Sciences Victoria University of WellingtonWellingtonNew Zealand

Conceptualizing species interactions as networks has broadened our understanding of ecological ***,the factors shaping interaction patterns among species and,therefore,network structure remain *** potentially important factor is the matching of phenotypic ***,we tested for trait matching in a bird–flower visitation network from New *** first quantified the overall network structure and tested whether flower size could account for differences in the visitation rates of flowering *** then explored the relationship between the flower size and bill *** results showed that the interaction network is *** species with large flowers received more visits from birds than plant species with small ***,plant species with large flowers were visited more frequently by birds with large bills,while species with smaller flowers were visited more frequently by birds with small ***,the interaction patterns between birds and flowering plants could be predicted by their morphology,suggesting that phenotypic trait matching is an important predictor of network structure.

关键词： bird-flower visitation network flower morphology plant-animal interactions size coupling

A Structural Bisulfite Assay to Identify DN Cruciforms

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Molecular Plant 2016年第9期9卷 1328-1336页

作者： matthew Gentry Lars Hennig Department of Plant Biology Uppsala BioCenter Swedish University of Agricultural Sciences and Linnean Center for Plant Biology 75007 Uppsala Sweden

In the half century since the discovery of the double-helix structure of DNA, it has become increasingly clear that DNA functionality is based on much more than its sequence in a double-helical structure. Further advances have highlighted the importance of additional aspects of DNA structure： its packaging in the higher order chromatin structure, positioning of nucleosomes along the DNA, and the occurrence of non-helical DNA structures. Of these, the latter has been problematic to prove empirically. Here, we describe a method that uses non-denaturing bisulfite sequencing on isolated Arabidopsis thaliana nuclei to determine the location of cytosines positioned outside the double helix as a result of non-B-form DNA structures. We couple this with computational methods and S1 nuclease digest to reliably identify stable, non-B-form, cruciform structures. This enables us to identify a palindrome in the promoter of FLOWERING LOCUS T that forms a stable non-B-form structure. The stronger conservation of the ability to form a nonhelical secondary structure than of the sequence suggests that this structure is biologically relevant.

关键词： DNA structure cruciform DNA genome organization

FTC of hidden Markov process with application to resource allocation in air operation

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Journal of Systems Engineering and Electronics 2011年第1期22卷 12-21页

作者： Neng Eva Wu matthew Charies Ruschmann Department of Electrical and Computer Engineering Binghamton UniversityState University of New York

This paper investigates the feedback control of hidden Markov process（HMP） in the face of loss of some observation *** control action facilitates or impedes some particular transitions from an inferred current state in the attempt to maximize the probability that the HMP is driven to a desirable absorbing *** control problem is motivated by the need for judicious resource allocation to win an air operation involving two opposing *** effectiveness of a receding horizon control scheme based on the inferred discrete state is *** to loss of sensors that help determine the state of the air operation is achieved through a decentralized scheme that estimates a continuous state from measurements of linear models with additive *** discrete state of the HMP is identified using three well-known detection *** sub-optimal control policy based on the detected state is implemented on-line in a closed-loop,where the air operation is simulated as a stochastic process with SimEvents,and the measurement process is simulated for a range of single sensor loss rates.

关键词： hidden Markov process(HMP) decentralization information fusion fault tolerant estimation air operation receding horizon control(RHC).

Nanovaccines for remodeling the suppressive tumor microenvironment： New horizons in cancer immunotherapy

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Frontiers of Chemical Science and Engineering 2017年第4期11卷 676-684页

作者： Shi, Kai Haynes, matthew Huang, Leaf Univ North Carolina Chapel Hill Eshelman Sch Pharm Div Mol Pharmaceut Chapel Hill NC 27599 USA

Despite limited successes in clinical develop- ment, therapeutic cancer vaccines have experienced resurgence in recent years due to an enhanced emphasis upon co-mitigating factors underlying immune response. Specifically, reversing the immune-suppressive effects of the tumor microenvironment, mediated by a variety of cellular and molecular signaling mechanisms, has become fundamental toward enhancing therapeutic efficacy. Therein, our lab has implemented various nano-vaccines based on the lipid-coated calcium phosphate platform for combined immunotherapy, in which antigenic, epitope- associated peptides as well as immune-suppression inhibitors can be co-delivered, often functioning through the same formulation. In probing the mechanism of action of such systems in vitro and in vivo, an improved effect synergy can be elucidated, inspiring future preclinical efforts and hope for clinical success.

关键词： vaccine nanoparticle tumor immunotherapy,microenvironment

Numerical estimates for the regularization of nonautonomous ill-posed problems

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International Journal of Modeling, Simulation, and Scientific Computing 2015年第1期6卷 123-144页

作者： matthew A.Fury Division of Science&Engineering Penn State Abington 1600 Woodland Road Abington PA 19001USA

The regularization of ill-posed problems has become a useful tool in studying initial value problems that do not adhere to certain desired properties such as continuous dependence of solutions on initial *** direct computation of the solution becomes difficult in this situation,many authors have alternatively approximated the solution by the solution of a closely defined well posed *** this paper,we demonstrate this process of regularization for nonautonomous ill-posed problems including the backward heat equation with a time-dependent diffusion *** the process,we provide two different approximate well posed models and numerically compare convergence rates of their solutions to a known solution of the original ill-posed problem.

关键词： Regularizing family of operators ill-posed problem backward heat equation

Quantum feedback networks and control:A brief survey

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Chinese Science Bulletin 2012年第18期57卷 2200-2214页

作者： JAMES matthew R ARC Centre for Quantum Computation and Communication Technology Research School of EngineeringAustralian National UniversityCanberraACT 0200Australia

The purpose of this paper is to provide a brief review of some recent developments in quantum feedback networks and control.A quantum feedback network (QFN) is an interconnected system consisting of open quantum systems linked by free fields and/or direct physical *** network constructs,including series connections as well as feedback loops,are *** quantum feedback network theory provides a natural framework for analysis and *** properties such as dissipation,stability,passivity and gain of open quantum systems are *** system design is also discussed,primarily in the context of open linear quantum stochastic *** issue of physical realizability is discussed,and explicit criteria for stability,positive real lemma,and bounded real lemma are *** for linear quantum systems,coherent H∞ and LQG control are described.

关键词：开放量子系统反馈网络控制系统有界实引理 LQG控制网络结构反馈回路网络理论

The Log-Concavity of Kazhdan-Lusztig Polynomials of Uniform Matroids

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Journal of Systems Science & Complexity 2023年第1期36卷 117-128页

作者： XIE matthew H Y ZHANG Philip B College of Science Tianjin University of TechnologyTianjin 300384China College of Mathematical Science Tianjin Normal UniversityTianjin 300387China

Elias,et al.(2016)conjectured that the Kazhdan-Lusztig polynomial of any matroid is *** by a computer proof of Moll’s log-concavity conjecture given by Kauers and Paule,the authors use a computer algebra system to pr... 详细信息

关键词： HolonomicFunctions Kazhdan-Lusztig polynomial log-concavity uniform matroid