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Numerical Analysis of Unconventional Forging Process of Hollowed Shaft from Ti-6Al-4V Alloy

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Journal of Shanghai Jiaotong university(Science) 2011年第2期16卷 157-161页

作者： GONTARZ Andrzej PATER zbigniew TOFIL Arkadiusz Department of Computer Modelling and Metal Forming Technologies Lublin University of Technology Technical Institute State School of Higher Education in Chelm

This paper presents theoretical analysis of unconventional forging process of hollowed shaft from Ti-6Al-4V alloy in a three-slide forging *** method in comparison with other metal forming methods allows for obtaining of hollowed *** designed process is verified theoretically by means of numerical simulations based on finite element method with assumption of 3D state of *** following factors are considered in the analysis:material flow kinematics,strain distribution,temperature distribution and force of *** the basis of results,it is stated that the application of designed technology allows for obtaining of a product of assumed quality.A comparison is made between material consumption in analyzed process and material consumption in typical metal forming methods,also in used at present technology of shaft manufacturing by machining *** is stated that the application of forging in the three-slide forging press allows for a considerable decrease of manufacturing costs due to material savings and decrease of labor consumption of operations at finishing.

关键词： hollowed shaft die forging three-slide forging press finite element method

A New Dynamical Evolutionary Algorithm Based on Statistical Mechanics

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Journal of Computer Science & Technology 2003年第3期18卷 361-368页

作者：李元香邹秀芬康立山 zbigniew Michalewicz Software Engineering Laboratory Wuhan University Wuhan 430072 P.R. China Computer Science Department University of North Carolina at Charlotte Charlotte NC 28223-0001 USA

In this paper, a new dynamical evolutionary algorithm (DEA) is presented basedon the theory of statistical mechanics. The novelty of this kind of dynamical evolutionary algorithmis that all individuals in a population (called particles in a dynamical system) are running andsearching with their population evolving driven by a nev selecting mechanism. This mechanismsimulates the principle of molecular dynamics, which is easy to design and implement. A basictheoretical analysis for the dynamical evolutionary algorithm is given and as a consequence twostopping criteria of the algorithm are derived from the principle of energy minimization and the lawof entropy increasing. In order to verify the effectiveness of the scheme, DEA is applied to solvingsome typical numerical function minimization problems which are poorly solved by traditionalevolutionary algorithms. The experimental results show that DEA is fast and reliable.

关键词： dynamical evolutionary algorithm statistical mechanics stopping criterion dynamical system

Prey reduce risk-taking and abundance in the proximity of predators

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Current Zoology 2017年第6期63卷 591-598页

作者： Anders. R MФLLER zbigniew KWIECINSKI Piotr TRYJANOWSKI Ecologie Systematique Evolution Universite Paris-Sud CNRS AgroParisTech Universite Paris-Saclay Orsay Cedex F-91405 France blnstitute of Zoology Poznan University of Life Science Wojska Polskiego 71C Poznan PL-60-625 Poland

Prey have evolved anti-predator defences that reduce or eliminate the risk of predation. Predators often reproduce at specific sites over many years causing permanent threats to local prey species. Such prey may respond by moving elsewhere thereby reducing local population abundance, or they may stay put and adjust their behavior to the presence of predators. We tested these predictions by analyzing population abundance and anti-predator behavior within 100 m of and 500 m away from nests of sparrowhawks Accipiter nisus and goshawks A. gentilis for 80 species of birds. Population abundance of prey was reduced by 11% near goshawk nests and by 15% near sparrowhawk nests when compared with nearby control sites in similar habitats. Flight initiation distance （FID） of prey, estimated as the distance at which birds took flight when approached by a human, increased by 50% in the presence of hawk nests, providing evidence of adjustment of anti-predator behavior to prevailing risks of predation. Susceptibility to predation was estimated as log transformed abundance of the observed number of prey items obtained from prey remains collected around nests minus log transformed expected number of prey according to point counts of breeding birds. FID increased from 10 to 46 m with increasing susceptibility of prey species to predation by the goshawk and from 12 to 15 m with increasing susceptibility of prey species to predation by the sparrowhawk. These findings suggest that prey adjust their distribution and anti-predator behavior to the risk of predation.

关键词： accipiter hawks FID flight initiation distance goshawk population abundance prey preference sparrowhawk.

Evolutionary approaches for supply chain optimisation Part I:single and two-component supply chains

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International Journal of Intelligent Computing and Cybernetics 2012年第4期5卷 444-472页

作者： Maksud Ibrahimov Arvind Mohais Sven Schellenberg zbigniew Michalewicz Department of Computer Science University of AdelaideAdelaideAustralia SolveIT Software AdelaideAustralia University of Adelaide AdelaideAustralia

Purpose–The purpose of this paper and its companion(Part II:multi-silo supply chains)is to investigate methods to tackle complexities,constraints(including time-varying constraints)and other *** tis part,the paper aims to devote attention to single silo and two-silo supply *** also aims to discuss three *** first model is based on the winebottling real-world system and exposes complexities of a single operational component of the supply *** second model extends it to two components:production and *** last system is a real-world implementation of the two-component supply ***/methodology/approach–Evolutionary approach is proposed for a single component *** two-component experimental supply chain is addressed by the algorithm based on cooperative *** final problem of steel sheet production is tackled with the evolutionary ***–The proposed systems produce solutions better than solutions proposed by human experts and in a much shorter ***/value–The paper discusses various algorithms to provide the decision support for the real-world *** proposed systems are in the production use.

关键词： Genetic algorithms Cooperative coevolution Coordinated supply chain Time-varying constraints Supply chain management Time-varying control systems

Evolutionary approaches for supply chain *** II:multi-silo supply chains

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International Journal of Intelligent Computing and Cybernetics 2012年第4期5卷 473-499页

作者： Maksud Ibrahimov Arvind Mohais Sven Schellenberg zbigniew Michalewicz Department of Computer Science University of AdelaideAdelaideAustralia SolveIT Software AdelaideAustralia

Purpose–The purpose of this paper and its companion(Part I:single and two-component supply chains)is to investigate methods to tackle complexities,constraints(including time-varying constraints)and other *** this part,attention is devoted to multi-silo supply chain and the relationships between the *** first part of the paper aims to consider two types of experimental supply chains:with one-to-many and many-to-one *** second half of the paper aims to present two approaches on optimising the material flow in the real-world supply chain ***/methodology/approach–Cooperative coevolutionary and classical sequential approaches are taken to address the experimental multi-silo supply *** to the nature and the complexity of the supply chain presented in the second half of the paper,evolutionary algorithm was not sufficient to tackle the problem.A fuzzy-evolutionary algorithm is proposed to address the ***–The proposed systems produce solutions better than solutions proposed by human experts and in much shorter ***/value–The paper discusses various algorithms to provide the decision support for the real-world *** system proposed for the real-world supply chain is in the process of integration to the production environment.

关键词： Genetic algorithms Cooperative coevolution Coordinated supply chain Time-varying constraints Time-varying control systems supply chain management

Luminescence study of europium(III) tris(β-diketonato)/phosphonate complexes in chloroform

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Journal of Rare Earths 2008年第2期26卷 185-191页

作者： Stefan Lis zbigniew Piskula Krzysztof Staninski Sayaka Tamaki Masayuki Inoue Yuko Hasegawa Department of Rare Earths Faculty of Chemistry Adam Mickiewicz University Grunwaldzka 6 Department of Chemistry Faculty of Science Science University of Tokyo

The extraction of Eu（Ⅲ） with β-diketone, HA, and monodentate or bidentate Lewis bases, B, into chloroform and the luminescence properties of the extracted species were studied. Pivaloyltrifluoroacetone, Hpta, and 2-thenoyltfifluoroacetone, Htta, were used as the β-diketones. The Lewis bases, B, were tetraethyl methylene diphosphonate, POPO, which was bidentate, and diethyl benzylphosphonate, PhPO which was monodentate. Based on the extraction data, the stability constants, log β, of the first complexes between tfis（β-diketonato）Eu（Ⅲ） and the phosphonate, EuA3B, were determined to be 6.0 for the POPO complex and 3.40 for the PhPO complex. The Eu（Ⅲ） luminescence intensity in the EuA3POPO was larger than EuA3 where A was either pta or tta at similar concentrations of Eu（Ⅲ）, while that in Eu（pta）3PhPO was stronger than EuA3; however, in Eu（tta）3PhPO, it was weaker than Eu（tta）3. The POPO functions as a sensitizer, and the PhPO functions as a quencher for the tta chelate and as a sensitizer for the pta chelate. From the lifetime and quantum yield, φ, of the Eu（Ⅲ） luminescence in the complexes as well as the observation of the extractability of Eu（Ⅲ） with the Hpta and the phosphonates and of the luminescence spectra of the complexes, it was confirmed that the extraction of Eu（Ⅲ） was remarkably enhanced with a β-diketonate and a strong Lewis base, and also the ternary complex that was formed as the extracted species, showed luminescence enhancement. This phenomenon may be due the formation of a strong bond between the Eu（Ⅲ） and the strong Lewis base leading to more hydrophobicity in the extracted species and also to more effective energy transfer from the Lewis base to the Eu（Ⅲ）. It was not significant whether the donor atoms were N or O.

关键词： tris(β-diketonato)Eu(Ⅲ) extraction luminescence phosphonate ligands rare earths

Adaptive control of anti-aircraft missile launcher mounted on a mobile base

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Theoretical & Applied Mechanics Letters 2012年第4期2卷 47-50页

作者： Izabela Krzysztofik zbigniew Koruba Department of Computer Technology and Armament Kielce University of Technology7 Aleja Tysiaclecia PP St.Kielce 24-314Poland

This paper presents the problem of control of anti-aircraft missile launcher mounted on a moving carrier-vehicle. Direct excitations on the vehicle from the road cause adverse vibrations of the launcher. In order to increase the precision of the guiding system in the conditions of self-propelled movement of the setup on a bumpy road, the adaptive control algorithm was proposed. Some research results of computer simulation are presented in a graphical form.

关键词： adaptive control anti-aircraft missile launcher

Boron nitride nanotube reinforced polyurethane composites

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Progress in Natural Science:Materials International 2013年第2期23卷 170-173页

作者： Luhua Li Ying Chen zbigniew H. Stachurski Institute for Frontier Materials Deakin University Geelong Waurn Ponds Campus Research School of Engineering College of Engineering and Computer Science The Australian National University

Bulk-sized boron nitride nanotube (BNNT) reinforced polyurethane (PU) composites at different volume contents have been produced. A large quantity of BNNT fillers are synthesized by a boron ink method. Compared to the neat PU, the 0.5 vol% and 2.0 vol% BNNT reinforced composites show 38.2% and 6.3% increases in compressive modulus, respectively. The relatively less enhanced compressive modulus of the 2.0 vol% composite may be due to the agglomerations of nanotubes at high volume percentages. Contrary to normal behaviour, the composites show decreasing Rockwell (HRR) hardness values with an increasing volume fraction.

关键词： Composite Boron nitride nanotube Compressive modulus Rockwell hardness

Recent advances and trends in roll bonding process and bonding model:A review

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Chinese Journal of Aeronautics 2023年第4期36卷 36-74页

作者： Zixuan LI Shahed REZAEI Tao WANG Jianchao HAN Xuedao SHU zbigniew PATER Qingxue HUANG College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030002China Institute of Materials Science Technische Universita¨t DarmstadtDarmstadt 64287Germany Faculty of Mechanical Engineering&Mechanics Ningbo UniversityNingbo 315211China Faculty of Mechanical Engineering Lublin University of TechnologyLublin20618Poland

This review presents a thorough survey of the roll bonding process with a focus on the bimetallic bars/tubes as well as the bonding models and *** review aims to provide insight into cold,hot and cryogenic bonding mechanisms at the micro and atomic scale and act as a guide for researchers working on roll bonding,other joining processes and bonding ***-while,the shortcomings of roll bonding processes are presented from the aspect of formable shapes,while bonding models are shown from the aspect of calculation time,convergence,interface behav-ior of dissimilar materials as well as hot bonding status *** well-accepted numerical methodologies of bonding models,namely the contact algorithm and cohesive zone model(CZM)of bonding models and in simulations of the bonding process are ***,recent advances and trends in the application of the combination of mechanical interlocking and metallurgical bonding,special energy fields,gradient structure,novel materials,green technology and soft computing method in the roll bonding process are also *** challenges for advancing and prospects of the roll bonding process and bonding model are presented in an attempt to shed some light on the future research direction.

关键词： Bimetallic Bonding mechanism Bonding model Numerical simulation Roll bonding process