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Study on copper adsorption on olivine

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Journal of university of science and technology Beijing 2001年第1期8卷 1-5页

作者： Rolf A. Kleiv, Lei Shao, Kunt L. Sandvik, Wei Wu, Cunyi Song Department of Geology and Mineral Resources Engineering, norwegian university of science and technology, 7034 Trondheim, Norway Resources Engineering School, university of science and Teclmolog Department of Geology Engineering Norwegian Univ. of Sci. and Technol. 7034 Trondheim Norway

The copper adsorption on olivine supplied by A/S Olivine production plant at Aheim in western Norway has been studied. The factors which affect the uptake of copper have been evaluated. The results reveal that the equilibrium PH in aqueous solution has the greatest influence on the copper adsorption thanks to the competitive adsorption between proton and copper ions, and the adsorption of copper to olivine increases rapidly with the pH increasing from 4 to 6. The initial copper concentration and olivine dose also possess significant effect on copper adsorption. The adsorption efficieny of copper increases with the increase of olivine dose or the decrease of initial copper concentration at the same pH. The ionic strength effect on the adsorption has also been investigated, but it owns little effect on the adsorption process of copper due to the formation of inner sphere surface complexation of copper on olivine. The experimental data show that olivine has a high acid buffer capacity and is an effective adsorbent for copper.

关键词： copper adsorption olivine ionic strength acid mine drainage

PERFORMANCE ANALYSIS OF OPTIMAL CHANNEL ESTIMATION AND MULTIUSER DETECTION IN A RANDOMLY-SPREAD CDMA CHANNEL

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Journal of Systems science & Complexity 2010年第1期23卷 22-34页

作者： Keigo TAKEUCHI Mikko VEHKAPER Toshiyuki TANAKA Ralf R.MLLER Department of Information and Communication Engineering University of Electro-Communications Department of Electronics and Telecommunications Norwegian University of Science and Technology Department of Systems science Graduate School of InformaticsKyoto University

This paper analyzes performance of optimal channel estimation and multiuser detection(MUD) in a block-fading code-division multiple-access (CDMA) channel on the assumptions of randomspreading and large-system limit,by using the replica method developed in statistical *** authors find that the asymptotic spectral efficiency of the linear minimum mean-squared error(LMMSE) MUD which was proposed and analyzed by Evans and Tse in 2000 is indistinguishable fromthat of the optimal MUD for small system *** results imply that performance of MUD scarcelyimproves even if one spends more computational cost than that of the LMMSE MUD,i.e.,at most thecube of the number of users,on the above-described conditions.

关键词： Channel estimation code-division multiple-access (CDMA) systems multiuser detection replica method spectral efficiency.

Determination of thermal conductivity of magnesium-alloys

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Journal of Central South university of technology 2001年第1期8卷 60-63页

作者： ZHOU Jie min 1,YANG Ying 1,Magne Lamvik 2,WANG Gang 1 (1.Department of Applied Physics and Heat Engineering, Central South university, Changsha 410083, China 2.norwegian university of science and technology) Department of Applied Physics and Heat Engineering Central South University Changsha China norwegian university of science and technology China

An indirect method, Angstroms method was adopted and an instrument was designed to determine the thermal conductivity of magnesium metal and alloys. Angstroms method is an axial periodic heat flow technique by which the thermal diffusivity can be measured directly. Then thermal conductivity can be obtained with relation to thermal diffusivity. Compared with the recommended data from the literature the fitted values of the thermal diffiusivity correspond with 3%, and the credible probability of the thermal conductivity in the range of 0 450 ℃ is about 95%. The method is applicable in the given temperature range.

关键词： angstroms method thermal conductivity thermal diffusivity magnesium alloy

Kinetics of the Oxidative Dehydrogenation of Propane over a VMgO Catalyst

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Journal of Energy Chemistry 2002年第Z1期 33-42页

作者： L.Late,E.A.BlekkanDepartment of Chemical Engineering, norwegian university of science and technology (NTNU), N-7491 Trondheim, Norway[Manuscript received June 6, 2002 revised July 2, 2002]

The reaction kinetics of the oxidative dehydrogenation of propane was studied at 475-550℃ over a VMgO catalyst. Vanadium-magnesium-oxides are among the most selective and active catalysts for the dehydrogenation of propane to propylene. Selectivity to propylene up to about 60% was obtained at 10% conversion, but the selectivity decreased with increasing conversion. No oxygenates were detected, the only by-products were CO and CO2. The reaction rate of propane was found to be first order in propane and close to zero order in oxygen, which is in agreement with a Mars van Krevelen mechanism with the activation of the hydrocarbon as the rate determining step. The activation energy of the conversion of propane was found to be 122±6 kJ/mol.

关键词： propane oxidative dehydrogenation VMgO kinetics

Ultrasonic focusing and scanning with multiple waves

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Chinese Physics B 2013年第1期22卷 312-317页

作者：张碧星刘冬冬师芳芳 Hefeng Dong State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Department of Electronics and Telecommunications Norwegian University of Science and Technology

This paper presents a new focusing and scanning method which focuses multiple waves on a target. The key of the method is to control excitation pulses for each element of the transducer array. The excitation pulse on each array element is obtained by time reversing the signal received by the same element, which is generated by an imaginary source at the target. The excitation pulses from all array elements are transmitted and arrive at the target simultaneously, and focusing is achieved. The performance of the two methods is compared in numerical examples, and it is demonstrated that the proposed method achieves a satisfactory focusing and a good signal-to-noise ratio no matter where the target location is.

关键词： ultrasonic focusing and scanning multiple waves transducer array

Dynamic Fuzzy Logic Control of Genetic Algorithm Probabilities

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Dynamic Fuzzy Logic Control of Genetic Algorithm Probabiliti...

2011 4th IEEE International Conference on Computer science and Information technology(ICCSIT 2011)

作者： Huijuan Guo Department of Computer science Taiyuan Normal university Taiyuan China Yi Feng Vanceinfo Technologies Inc. Beijing China Shengtong Zhong Department of Computer and Information science norwegian university of science and technology Trondheim Norway

Genetic algorithms are traditionally used to solve combinatorial optimization *** implementation of Genetic algorithms involves of using genetic operators（crossover, mutation,selection,etc.）.Meanwhile,parameters（such as pop- ulation size,probabilities of crossover and mutation）of Genetic algorithm need to be chosen or *** this paper,we propose a hybrid Fuzzy-Genetic Algorithm（FLGA）approach to solve the multiprocessor scheduling *** on tractional Genetic algorithms,a fuzzy logic controller is added to tune parameters dynamically which potentially can improve the overall perfor- *** detail,the probabilities of crossover and mutation is tuned by a fuzzy logic controller based on fuzzy *** to the Standard Genetic Algorithm（SGA）,the experiments results clearly show that the FLGA method performs significantly better.

关键词： Multiprocessor Scheduling Problem Hybrid Fuzzy-Genetic Algorithm

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对用BBK规则衡量信托的评论(英文)

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“科技增强国力，青年开创未来——携手走向辉煌的新世纪”中国科协第三届青年学术年会

作者： Haibo Xiao (Department of Telematics,The norwegian university of science and technology,Norway)

At ESORICS-94,Beth,Borcherding and Klein presented a paper called Valuation of Trust in Open Networks which describes a scheme for valuation of trust in distributed *** scheme contains several weaknesses which can produce wrong trust values and which would make systems that depend on it easy targets for malicious *** paper describes these weaknesses and gives some suggestions on how trust can be studied.

关键词： Trust Reliability Security Distributed systems

Adaptive Neural Network Control of Uncertain Nonlinear Plants with Input Saturation

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Adaptive Neural Network Control of Uncertain Nonlinear Plant...

2009中国控制与决策会议

作者： Jing Zhou * Petroleum Department,International Research Institute of Stavanger,N-5008 Bergen,Norway ** Department of Engineering Cybernetics,norwegian university of science and technology,N-7491 Trondheim,Norway.

＜正＞In this paper,an adaptive controller is developed for uncertain nonlinear systems in the presence of input saturation. The control design is achieved by using backstepping technique with neural network *** some existing control schemes for systems with input saturation,the developed controller does not require uncertain parameters within a known compact *** showing stability,transient performance is also established and can be adjusted by tuning certain design *** results obtained on a drilling system are presented to demonstrate the effectiveness of the proposed control scheme.

关键词： Adaptive control backstepping saturation neural networks

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连铸操作和钢清洁度控制

连铸操作和钢清洁度控制

2005中国钢铁年会

作者： Lifeng Zhang (Professor at the Department of Materials science & Engineering, norwegian university of science & technology, 7491 Trondheim, Norway, perryzhang2002@163. com)

该文分析了连铸操作在夹杂物和钢清洁度改善上的影响。首先综述了钢中夹杂物气孔和缺陷,夹杂物类别以及夹杂物析出和长大的机理。然后介绍了改善夹杂物去除和提高钢洁净度的铸机操作。有关夹杂物和纯度的现象或参数详述如下:表面现象和... 详细信息

该文分析了连铸操作在夹杂物和钢清洁度改善上的影响。首先综述了钢中夹杂物气孔和缺陷,夹杂物类别以及夹杂物析出和长大的机理。然后介绍了改善夹杂物去除和提高钢洁净度的铸机操作。有关夹杂物和纯度的现象或参数详述如下:表面现象和卷渣,流体流动形态,拉速,铸机弧形半径,电磁工艺和结晶器保护渣。本文为改善钢的质量提供了有用信息。

关键词：夹杂物缺陷连铸上表面现象和卷渣流体流动形态拉速连铸机弧形半径电磁工艺结晶器保护渣