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Coupling within Fluvial Geomorphic Systems:Spatial and Temporal Implications

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Journal of Earth Science 2000年第1期19卷 11-29页

作者： Adrian M Harvey department of Geography, university of liverpool, liverpool l69 3BX, England

Coupling within fluvial systems relates to the connectivity between the various components of the system. It can be viewed at several scales from local scales of hillslopetochannel and reachtoreach coupling, to larger scales of zonal coupling between the major functional zones of the fluvial system, and to the scale of regional coupling. Coupling influences how the system responds to environmental change and how the effects of environmental change are propagated through the system. This paper provides a review, based largely on previously published work, of the coupling concept, and how the effective temporal scales vary with the spatial scale of coupling. local scale coupling is considered through the hillslope to channel coupling in the Howgill Fells, northwest England, observed over a 30year monitoring period, together with examples from badlands in Spain, and reachtoreach coupling on the River Dane, northwest England. At the zonal scale the relative influence of climatic and baselevel change on coupling through dryregion alluvial fans is considered on fan systems in Spain, Nevada, and UAE/Oman. For large scale regional coupling, the response of the Tabernas basin, southeast Spain to tectonic uplift, is examined. The factors influencing coupling mechanisms vary with temporal and spatial scales. At the hillslopetochannel scale the significant factors are the magnitude and frequency characteristics of sediment generation and removal mechanisms within the context of progressive morphological change. Effective timescales range from the individual event to decadal timescales. At the zonal scale, that of alluvial fans, the significant factors are climatic change, and particularly in the appropriate morphological setting, baselevel change. Effective timescales are of the order of hundreds to thousands of years. At the regional scale, the response to tectonic uplift may take >100 ka to be transmitted through the drainage basin.

关键词： fluvial system coupling gully systems alluvial fans climatic change base level tectonics.

An improved group search optimizer for mechanical design optimization problems

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Progress in Natural Science:Materials International 2009年第1期19卷 91-97页

作者： Hai Shena,b,c,Yunlong Zhu a,Ben Niu a,b,Q.H.Wu d a Key laboratory of Industrial Informatics,Shenyang Institute of Automation,Chinese Academy of sciences,Shenyang 110016,China b Graduate School of the Chinese Academy of sciences,Beijing 100049,China c College of Physics Science and Technology,Shenyang Normal university,Shenyang 110034,China d department of Electrical Engineering and Electronics,the university of liverpool,Brownlow Hill,liverpool,l69 3GJ,uk [a]Key laboratory of Industrial Informatics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China [b]Graduate School of the Chinese Academy of Sciences Beijing 100049 China [c]College of Physics Science and Technology Shenyang Normal University Shenyang 110034 China [d]Department of Electrical Engineering and Electronics The University of Liverpool Brownlow Hill Liverpool L69 3GJ UK

This paper presents an improved group search optimizer(iGSO) for solving mechanical design optimization *** the proposed algorithm,subpopulations and a co-operation evolutionary strategy were adopted to improve the global search capability and convergence *** iGSO is evaluated on two optimization problems of classical mechanical design:spring and pressure *** experimental results are analyzed in comparison with those reported in the *** results show that iGSO has much better convergence performance and is easier to implement in comparison with other existing evolutionary algorithms.

关键词： Mechanical optimization problem GSO Constrained optimization problem

SOME PROPERTIES OF lSQR FOR lARGE SPARSE lINEAR lEAST SQUARES PROBlEMS

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Journal of Systems Science & Complexity 2010年第4期23卷 815-821页

作者： Zhongxiao JIA department of mathematical sciences,Tsinghua university,Beijing 100084,China. department of mathematical sciences Tsinghua University

It is well-known that many Krylov solvers for linear systems,eigenvalue problems,andsingular value decomposition problems have very simple and elegant formulas for residual *** not only allow us to further understand the methods theoretically but also can be usedas cheap stopping criteria without forming approximate solutions and residuals at each step beforeconvergence takes *** for large sparse linear least squares problems is based on the lanczosbidiagonalization process and is a Krylov ***,there has not yet been an analogouslyelegant formula for residual *** paper derives such kind of *** addition,the authorgets some other properties of lSQR and its mathematically equivalent CGlS.

关键词： CGlS krylov subspace lanczos bidiagonalization least squares lsqr normal equations.

Optimal variational principle for backward stochastic control systems associated with lévy processes

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Science China Mathematics 2012年第4期55卷 745-761页

作者： TANG MaoNing 1 & ZHANG Qi 2,1 department of mathematical sciences,Huzhou university,Huzhou 313000,China 2 School of mathematical sciences,Fudan university,Shanghai 200433,China 1. department of mathematical sciences Huzhou University Huzhou 313000 China2. School of Mathematical Sciences Fudan University Shanghai 200433 China

The paper is concerned with optimal control of backward stochastic differentiM equation （BSDE） driven by Teugel＇s martingales and an independent multi-dimensional Brownian motion, where Teugel＇s martingales are a family of pairwise strongly orthonormal martingales associated with l6vy processes （see e.g., Nualart and Schoutens＇ paper in 2000）. We derive the necessary and sufficient conditions for the existence of the optimal control by means of convex variation methods and duality techniques. As an application, the optimal control problem of linear backward stochastic differential equation with a quadratic cost criteria （or backward linear-quadratic problem, or BlQ problem for short） is discussed and characterized by a stochastic Hamilton system.

关键词： stochastic control stochastic maximum principle ldvy processes Teugel's martingales backwardstochastic differential equations

Structural signature and contact force distributions in the simulated three-dimensional sphere packs subjected to uniaxial compression

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Science China(Physics,Mechanics & Astronomy) 2010年第5期53卷 892-904页

作者： lIU lianFeng1,2,ZHANG lei1 & lIAO ShuFang1 1 department of mathematical sciences,Xi’an Jiaotong-liverpool university,Suzhou 215123,China 2 School of Science,Xi’an Jiaotong university,Xi’an 710049,China 1. department of mathematical sciences Xi’an Jiaotong-Liverpool University Suzhou 215123 China2. School of Science Xi’an Jiaotong University Xi’an 710049 China

Packing of spherical particles in a three-dimensional cylindrical container is simulated by using Discrete Element *** packed bed of spheres is also subjected to vertical compression which results in a dense *** of the packing during compaction are examined in detail in terms of the contact number,deviator fabric,and radial distribution ***,contact force distributions are measured at different locations in the pack,*** centre,the side wall,and the base(or bottom wall) of the *** simulations show that random close packing(RCP) tends to exist in the centre of the pack,while ordered packing structures exist near the container's *** uniaxial compression doesn't seem to alter the packing structure in the pack centre remarkably,but to reduce the structural anisotropy of the packing close to the container's *** simulated results have also helped to establish the correlations between packing structures and contact force ***,it is shown that small contact force distributions are sensitive to local packing *** simulated results are shown to be consistent with the recent experimental and simulation findings.

关键词： packing contact force distribution discrete element method particles boundary effect

Prognostic impact of preoperative nutritional and immune inflammatory parameters on liver cancer

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 266-269页

作者： Sung uk Bae department of Surgery School of MedicineDongsan Medical CenterKeimyung UniversityDaegu KS002South Korea

The immune response to tissue damage or infection involves inflammation,a multifaceted biological process distinguished by immune cell activation,mediator secretion,and immune cell recruitment to the site of *** blood-based immune-inflammatory biomarkers with prognostic significance in malignancies have been *** this issue of the World Journal of Gastrointestinal Surgery,they examined the prognosis of liver cancer radical resection in relation to pre-operative systemic immune-inflammation and nutritional risk *** older and younger individuals often reveals compromised nutritional and immu-nological statuses in the ***,performing preoperative evaluations of the nutritional status and immunity in geriatric patients is *** addition to being a primary treatment modality,radical resection is associated with a sig-nificant mortality rate following *** dietary consump-tion and an elevated metabolic rate within tumor cells contribute to the increased proba-bility of malnutrition associated with the ailment,consequently leading to a sub-stantial deterioration in *** studies,reinforce the importance of nu-tritional and immune-inflammatory *** to surgical intervention,geriatric nutritional risk and systemic immune-inflammatory indices should be prioritized,particularly in older patients with malignant diseases.

关键词： Systemic immune inflammation index Nutritional risk index Radical resection liver cancer Prognosis Correlation

Fast Training of Support Vector Machines Using Error-Center-Based Optimization

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International Journal of Automation and computing 2005年第1期2卷 6-12页

作者： l. Meng, Q. H. Wu department of Electrical Engineering and Electronics, the university of liverpool, liverpool, l69 3GJ, uk department of Electrical Engineering and Electronics The University of Liverpool Liverpool UK

This paper presents a new algorithm for Support Vector Machine (SVM) training, which trains a machine based on the cluster centers of errors caused by the current machine. Experiments with various training sets show that the computation time of this new algorithm scales almost linear with training set size and thus may be applied to much larger training sets, in comparison to standard quadratic programming (QP) techniques.

关键词： Support vector machines quadratic programming pattern classification machine learning

Cross-Domain Bilateral Access Control on Blockchain-Cloud Based Data Trading System

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Computer Modeling in Engineering & sciences 2024年第10期141卷 671-688页

作者： Youngho Park Su Jin Shin Sang uk Shin Electronics and Information Communications Research Center Pukyong National UniversityBusan48513Republic of Korea department of Information Security Graduate SchoolPukyong National UniversityBusan48513Republic of Korea Division of Computer Engineering Pukyong National UniversityBusan48513Republic of Korea

Data trading enables data owners and data requesters to sell and purchase *** the emergence of blockchain technology,research on blockchain-based data trading systems is receiving a lot of ***,to reduce the on-chain storage cost,a novel paradigm of blockchain and cloud fusion has been widely considered as a promising data trading ***,the fact that data can be used for commercial purposes will encourage users and organizations from various fields to participate in the data *** the data marketplace,it is a challenge how to trade the data securely outsourced to the external cloud in a way that restricts access to the data only to authorized users across multiple *** this paper,we propose a cross-domain bilateral access control protocol for blockchain-cloud based data trading *** consider a system model that consists of domain authorities,data senders,data receivers,a blockchain layer,and a cloud *** proposed protocol enables access control and source identification of the outsourced data by leveraging identity-based cryptographic *** the proposed protocol,the outsourced data of the sender is encrypted under the target receiver’s identity,and the cloud provider performs policy-match verification on the authorization tags of the sender and receiver generated by the identity-based signature ***,data trading can be achieved only if the identities of the data sender and receiver simultaneously meet the policies specified by each *** demonstrate efficiency,we evaluate the performance of the proposed protocol and compare it with existing studies.

关键词： Bilateral access control blockchain data sharing policy-match

Dimensions of a class of high-dimensional homogeneous Moran sets and Moran classes

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Progress in Natural Science:Materials International 2002年第9期12卷 17-22页

作者： YAN Ping(department of mathematical sciences, Tsinghua university, Beijing 100084, China) Tsing Hua Univ Dept Math Sci Beijing 100084 Peoples R China

A class of high-dimensional homogeneous Moran sets and Moran classes are introduced and some dimensional properties are studied. The Hausdorff dimension, modified lower box-counting dimension, lower and upper box-counting dimension, and packing dimension of high-dimensional homogeneous and partial homogeneous Cantor sets are determined. Moreover, a kind of fractal E is obtained, which is not regular but with the property Dimw(Ed) = dDimw(E), where w denotes any of the dimensions mentioned above.

关键词： Moran set Moran class homogeneous Cantor set partial homogeneous Cantor set dimension.