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Full-Text Articles in Social and Behavioral Sciences

Dynamic Response Analysis Of The Rotating Blade Of Horizontal Axis Wind Turbine, Xiong Liu, Xianmin Zhang, Gangqiang Li, Yan Chen, Zhiquan Ye Jan 2010

Dynamic Response Analysis Of The Rotating Blade Of Horizontal Axis Wind Turbine, Xiong Liu, Xianmin Zhang, Gangqiang Li, Yan Chen, Zhiquan Ye

Faculty of Engineering and Information Sciences - Papers: Part A

This paper presents a dynamic response analysis of the blade of horizontal axis wind turbines using finite element method. The blade is treated as a cantilever and modeled with two-node beam element. The blade element-momentum theory is applied to calculate the aerodynamic loads. Dynamic inflow and dynamic stall are taken into account to reflect the transient aerodynamics. The centrifugal stiffening is introduced to consider the restoring effects of centrifugal force. An aerodynamic damping model is presented for calculating the overall damping ratio instantaneously during time-domain simulation. The structural dynamic equation is solved using Newmark method and the overall dynamic response ...


A Hybrid Highly Birefringent Fiber Optic Sensing System For Simultaneous Strain And Temperature Measurement, Piotr Lesiak, Ginu Rajan, Yuliya Semenova, Gerald Farrell, Anna Boczkowska, Andrzej Domanski, Tomasz Wolinski Jan 2010

A Hybrid Highly Birefringent Fiber Optic Sensing System For Simultaneous Strain And Temperature Measurement, Piotr Lesiak, Ginu Rajan, Yuliya Semenova, Gerald Farrell, Anna Boczkowska, Andrzej Domanski, Tomasz Wolinski

Faculty of Engineering and Information Sciences - Papers: Part A

A novel hybrid fiber optic sensor based on integration of polarimetric fiber sensors for simultaneous strain and temperature measurement is presented in this paper. Two types of polarimetric fibers are used: a side-hole fiber and a polarization maintaining photonic crystal fiber. The disadvantage of each sensor type can be overcome by using the sensors in a complementary manner to measure temperature independently from average strain. © 2010 Photonics Society of Poland.


Simulation Of Macroscopic Deformation Using A Sub-Particle Dem Approach, Leela Kempton, David J. Pinson, Sheng Chew, Paul Zulli, Aibing Yu Jan 2010

Simulation Of Macroscopic Deformation Using A Sub-Particle Dem Approach, Leela Kempton, David J. Pinson, Sheng Chew, Paul Zulli, Aibing Yu

Faculty of Engineering and Information Sciences - Papers: Part A

A limitation in numerical modelling of the ironmaking blast furnace is the lack of ability to quantify the effects of particle deformation and subsequent loss of porosity arising from the softening and melting of ferrous materials. Previous attempts to consider deformation focussed solely on the macroscopic effects such as resistance to gas flow, with an assumed decrease in porosity proportional to temperature. Instead, it is proposed to approximate particle scale deformation using a modified subparticle Discrete Element Method approach, where each 'ore' particle is represented using an agglomerate of discrete elements with temperature dependent properties. Cohesive forces binding the agglomerate ...


Comparison Of Thermal Stability In Max211 And 312 Phases, Wei Kong Pang, It-Meng Low, B H. O'Connor, Andrew J. Studer, Vanessa Peterson, Zheng-Ming Sun, J P. Palmquist Jan 2010

Comparison Of Thermal Stability In Max211 And 312 Phases, Wei Kong Pang, It-Meng Low, B H. O'Connor, Andrew J. Studer, Vanessa Peterson, Zheng-Ming Sun, J P. Palmquist

Faculty of Engineering and Information Sciences - Papers: Part A

The susceptibility of four MAX phases (Ti2AlC, Cr2AlC, Ti3AlC2, and Ti3SiC2) to high-temperature thermal dissociation in vacuum has been investigated using in-situ neutron diffraction.


Thrust And Bending Moment Of Rigid Piles Subjected To Moving Soil, Wei-Dong Guo, H Y. Qin Jan 2010

Thrust And Bending Moment Of Rigid Piles Subjected To Moving Soil, Wei-Dong Guo, H Y. Qin

Faculty of Engineering and Information Sciences - Papers: Part A

An experimental apparatus was developed to investigate the behaviour of vertically loaded free-head piles in sand undergoing lateral soil movement(wf). A large number of tests have been conducted to date. Presented herein are 14 typical model pile tests concerning 2 diameters, 2 vertical pile loading levels, and varying sliding depths with the movement Wf driven by a triangular loading block. The results are provided regarding driving force, and induced shear force (T), bending movement (M) and deflection (y) along the piles with Wf/ normalised sliding depth. The tests enable simple expressions to be proposed, capitalised on theory for laterally ...


Model Tests On Free-Standing Passive Pile Groups In Sand, Wei-Dong Guo, E. H. Ghee Jan 2010

Model Tests On Free-Standing Passive Pile Groups In Sand, Wei-Dong Guo, E. H. Ghee

Faculty of Engineering and Information Sciences - Papers: Part A

A number of tests have been conducted to investigate response of vertically loaded capped pile groups in sand undergoing uniform lateral soil movement. The development of shear force, bending moment and deflection along the piles was measured. Presented in this paper are 4 tests on 2-pile free-standing groups, with a view to establish solutions for predicting the pile response. It was concluded that (1) maximum bending moment Mmax is largely linearly related to the sliding force Tmax in stable and moving layers; (2) The combined impact of pile-cap fixity, soil movement profiles, and axial load may be quantified by a ...


Bauschinger Effect In Microalloyed Steels: Part I. Dependence On Dislocation-Particle Interaction, Andrii Kostryzhev, Martin Strangwood, Claire L. Davis Jan 2010

Bauschinger Effect In Microalloyed Steels: Part I. Dependence On Dislocation-Particle Interaction, Andrii Kostryzhev, Martin Strangwood, Claire L. Davis

Faculty of Engineering and Information Sciences - Papers: Part A

The Bauschinger effect (yield stress decreasing at the start of reverse deformation after forward prestrain) is an important factor in strength development for cold metal forming technology. In steels, the magnitude of the Bauschinger effect depends on composition, through the presence of microalloy precipitates, and prior processing, through the size and distribution of microalloy precipitates and presence of retained work hardening. In this article, the microstructures of two (Nb- and Nb-V-microalloyed) steel plates, in terms of (Ti,Nb,V,Cu)-rich particle distributions and dislocation densities, have been quantitatively related to the Bauschinger parameters for the same processing conditions. For ...


Organisational Culture And Organisational Impacts Of Information Systems: A Review Of The Empirical Literature, Fei Peng, Rajeev Sharma, Sherah Kurnia, Reeva Lederman, Suelette Dreyfus Jan 2010

Organisational Culture And Organisational Impacts Of Information Systems: A Review Of The Empirical Literature, Fei Peng, Rajeev Sharma, Sherah Kurnia, Reeva Lederman, Suelette Dreyfus

Faculty of Engineering and Information Sciences - Papers: Part A

Organisational culture is an important influence in shaping the organisational impacts of Information Systems. However, the conceptualisation and operationalisation of culture in empirical studies does not reflect the richness of the theoretical literature. In particular, our review finds that the dynamic, emergent and reciprocal nature of the IS-culture relationship has not been adequately examined in the empirical literature. This is partly due to the methodologies employed in existing research. Suggestions for enriching empirical research into the ISculture relationship are discussed.


A Critique Of The Marker Variable Technique: The Effect Of Alternative Marker Variable Criteria, Rajeev Sharma, Philip Yetton, Jeff Crawford Jan 2010

A Critique Of The Marker Variable Technique: The Effect Of Alternative Marker Variable Criteria, Rajeev Sharma, Philip Yetton, Jeff Crawford

Faculty of Engineering and Information Sciences - Papers: Part A

The marker variable technique offers a practical and easy method to address the validity threat on account of common method variance to the findings of individual studies. Hawever, the validity of the marker variable technique has not been established. This paper examines the validity threat to the marker variable technique arising from multiple criteria for the selection of the marker variable proposed in the literature. Our findings shaw that the conclusions that can be drawn under different criteria are significantly and substantially different, raising doubts about the validity of the marker variable technique. Proposals for developing theoretically grounded criteria for ...


Seven-Level Cascaded Anpc-Based Multilevel Converter, Sridhar R. Pulikanti, Georgios S. Konstantinou, Vassilios G. Agelidis Jan 2010

Seven-Level Cascaded Anpc-Based Multilevel Converter, Sridhar R. Pulikanti, Georgios S. Konstantinou, Vassilios G. Agelidis

Faculty of Engineering and Information Sciences - Papers: Part A

A seven-level converter based on the cascaded connection of a three-level active neutral-point-clamped (ANPC) converter and individual H-bridge cells per phase is presented in this paper. This converter only requires a single DC source for all three phases and extends the amplitude of output voltage of the converter with similar DC-link voltage. The operation principles and control strategies based on a fundamental frequency harmonic elimination PWM are discussed. The regulation of FC voltage depends on the positions of switching angles over a quarter period in the available solutions and on the load power factor. In order to extend the regulation ...


Efficient Structured Support Vector Regression, Ke Jia, Lei Wang, Nianjun Liu Jan 2010

Efficient Structured Support Vector Regression, Ke Jia, Lei Wang, Nianjun Liu

Faculty of Engineering and Information Sciences - Papers: Part A

Support Vector Regression (SVR) has been a long standing problem in machine learning, and gains its popularity on various computer vision tasks. In this paper, we propose a structured support vector regression framework by extending the max-margin principle to incorporate spatial correlations among neighboring pixels. The objective function in our framework considers both label information and pairwise features, helping to achieve better cross-smoothing over neighboring nodes. With the bundle method, we effectively reduce the number of constraints and alleviate the adverse effect of outliers, leading to an efficient and robust learning algorithm. Moreover, we conduct a thorough analysis for the ...


A Multi-Resolution Approach To Learning With Overlapping Communities, Lei Tang, Xufei Wang, Huan Liu, Lei Wang Jan 2010

A Multi-Resolution Approach To Learning With Overlapping Communities, Lei Tang, Xufei Wang, Huan Liu, Lei Wang

Faculty of Engineering and Information Sciences - Papers: Part A

The recent few years have witnessed a rapid surge of par- ticipatory web and social media, enabling a new laboratory for studying human relations and collective behavior on an unprecedented scale. In this work, we attempt to harness the predictive power of social connections to determine the preferences or behaviors of individuals such as whether a user supports a certain political view, whether one likes one product, whether he/she would like to vote for a presidential candidate, etc. Since an actor is likely to participate in mul- tiple dierent communities with each regulating the actor's behavior in varying ...


A Scalable Algorithm For Learning A Mahalanobis Distance Metric, Junae Kim, Chunhua Shen, Lei Wang Jan 2010

A Scalable Algorithm For Learning A Mahalanobis Distance Metric, Junae Kim, Chunhua Shen, Lei Wang

Faculty of Engineering and Information Sciences - Papers: Part A

A distance metric that can accurately re°ect the intrinsic characteristics of data is critical for visual recognition tasks. An e®ective solution to de¯ning such a metric is to learn it from a set of training sam- ples. In this work, we propose a fast and scalable algorithm to learn a Ma- halanobis distance. By employing the principle of margin maximization to secure better generalization performances, this algorithm formulates the metric learning as a convex optimization problem with a positive semide¯nite (psd) matrix variable. Based on an important theorem that a psd matrix with trace of one ...


Coastal Reservoir In Murray-Darling River And Its Useful Experience For Yellow River, Shu-Qing Yang Jan 2010

Coastal Reservoir In Murray-Darling River And Its Useful Experience For Yellow River, Shu-Qing Yang

Faculty of Engineering and Information Sciences - Papers: Part A

this paper deals with the similarities between the Yellow River Basin and Murray - Darling River Basin. It is found that two of them are facing similar problems, such as water shortage, poor quality for water supply and decreasing runoff etc. Two basins suffer the sharp temporal and spatial variation in water resources, which results in flood threat and water stress alternatively. Consequently these two rivers have attracted global attention due to their significant impacts on their local economical development and ecological system. To alleviate the water stress conditions, this paper investigates the feasibility of coastal reservoirs at the river mouths ...


Computational Intelligence For Carbon-Centric Computing, John Fulcher Jan 2010

Computational Intelligence For Carbon-Centric Computing, John Fulcher

Faculty of Engineering and Information Sciences - Papers: Part A

The focus of this paper is twofold: firstly we make a case for the use of Computational Intelligence (CI) techniques in the modelling and/or prediction of global weather, CO2 emissions, climate change and similar endeavours. CI exploits processes found in Nature, albeit by way of software simulations on digital computers (i.e. in silico), and excel in particular at pattern recognition and/or classification. Moreover, they are characterized as being non-algorithmic, bottom-up, data-driven, and learn-by-example. The second focus of this paper is to propose the use of carbonrather than silicon-based computing, specifically in the form of DNA (or molecular ...


On Pogorelov Estimates For Monge-Ampere Type Equations, Jiakun Liu, Neil Trudinger Jan 2010

On Pogorelov Estimates For Monge-Ampere Type Equations, Jiakun Liu, Neil Trudinger

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, we prove interior second derivative estimates of Pogorelov type for a general form of Monge-Ampère equation which includes the optimal transportation equation. The estimate extends that in a previous work with Xu-Jia Wang and assumes only that the matrix function in the equation is regular with respect to the gradient variables, that is it satisfies a weak form of the condition introduced previously by Ma,Trudinger and Wang for regularity of optimal transport mappings. We also indicate briefly an application to optimal transportation.


Harmonic Elimination Control Of A Five-Level Dc-Ac Cascaded H-Bridge Hybrid Inverter, Georgios S. Konstantinou, Sridhar R. Pulikanti, Vassilios G. Agelidis Jan 2010

Harmonic Elimination Control Of A Five-Level Dc-Ac Cascaded H-Bridge Hybrid Inverter, Georgios S. Konstantinou, Sridhar R. Pulikanti, Vassilios G. Agelidis

Faculty of Engineering and Information Sciences - Papers: Part A

A five-level hybrid cascaded inverter operating under selective harmonic elimination (SHE) pulse-width modulation (PWM) control is discussed in this paper. The topology is a cascaded connection of a conventional three-phase, two-level inverter and an H-bridge module for each phase with a single DC-source. The topology boosts the output voltage within limits and with no additional DC-DC converters. However, such boosting feature depends on the control of the floating capacitor voltage and the load power factor. The regulation of the floating capacitor for the given modulation strategy is also analyzed. Experimental results taken from a single-phase laboratory prototype are presented to ...


Mechanism Of Sediment Transport In Uni-Directional, Bi-Directional Flows, Shu-Qing Yang Jan 2010

Mechanism Of Sediment Transport In Uni-Directional, Bi-Directional Flows, Shu-Qing Yang

Faculty of Engineering and Information Sciences - Papers: Part A

The aim of the present study is to investigate the relationship between flow strength and sediment discharge. The appropriate definition of energy dissipation rate E in Bagnold's theorem is discussed and it is found that the sediment transport rate g, in unidirectional and bi-directional flows can be well predicted when E is defined as the product of bed shear stress T. and near bed velocity u. then the linear relationship between u. E and the sediment transport rate is examined using measured data. The good agreement between measured and predicted values indicates that the phenomena of sediment transport can ...


A Λ-Cut And Goal-Programming-Based Algorithm For Fuzzy-Linear Multiple-Objective Bilevel Optimization, Ya Gao, Guangquan Zhang, Jun Ma, Jie Lu Jan 2010

A Λ-Cut And Goal-Programming-Based Algorithm For Fuzzy-Linear Multiple-Objective Bilevel Optimization, Ya Gao, Guangquan Zhang, Jun Ma, Jie Lu

Faculty of Engineering and Information Sciences - Papers: Part A

Bilevel-programming techniques are developed to handle decentralized problems with two-level decision makers, which are leaders and followers, who may have more than one objective to achieve. This paper proposes a λ-cut and goal-programming-based algorithm to solve fuzzy-linear multiple-objective bilevel (FLMOB) decision problems. First, based on the definition of a distance measure between two fuzzy vectors using λ-cut, a fuzzy-linear bilevel goal (FLBG) model is formatted, and related theorems are proved. Then, using a λ-cut for fuzzy coefficients and a goal-programming strategy for multiple objectives, a λ-cut and goal-programming-based algorithm to solve FLMOB decision problems is presented. A case study for ...


Collaborative Management Of Web Ontology Data With Flexible Access Control, Jie Lu, Chao Wang, Guangquan Zhang, Jun Ma Jan 2010

Collaborative Management Of Web Ontology Data With Flexible Access Control, Jie Lu, Chao Wang, Guangquan Zhang, Jun Ma

Faculty of Engineering and Information Sciences - Papers: Part A

The creation and management of ontology data on web sites (e.g. instance data that is used to annotate web pages) is important technical support for the growth of the semantic web. This study identifies some key issues for web ontology data management and describes an ontology data management system, called robinet, to perform the management. This paper presents the structure of the system and introduces a Web ontology data management model that enables a flexible access control mechanism. This model adds rules into the robinet system to utilize the semantics of ontology for controlling the access to ontology data ...


Team Situation Awareness Measure Using Semantic Utility Functions For Supporting Dynamic Decision-Making, Jun Ma, Jie Lu, Guangquan Zhang Jan 2010

Team Situation Awareness Measure Using Semantic Utility Functions For Supporting Dynamic Decision-Making, Jun Ma, Jie Lu, Guangquan Zhang

Faculty of Engineering and Information Sciences - Papers: Part A

Team decision-making is a remarkable feature in a complex dynamic decision environment, which can be supported by team situation awareness. In this paper, a team situation awareness measure (TSAM) method using a semantic utility function is proposed. The semantic utility function is used to clarify the semantics of qualitative information expressed in linguistic terms. The individual and team situation awareness are treated as linguistic possibility distributions on the potential decisions in a dynamic decision environment. In the TSAM method, team situation awareness is generated through reasoning and aggregating individual situation awareness based on a multi-level hierarchy mental model of the ...


Spatial And Temporal Interpolation Of Environmental Data, Tom Smith, Phil Jones, Elizabeth Kent, Maurice Cox, Noel A. Cressie, Dick Dee, Richard Smith Jan 2010

Spatial And Temporal Interpolation Of Environmental Data, Tom Smith, Phil Jones, Elizabeth Kent, Maurice Cox, Noel A. Cressie, Dick Dee, Richard Smith

Faculty of Engineering and Information Sciences - Papers: Part A

Environmental data analyzed to a regular spatial and temporal grid is often desired for monitoring and climate studies. For example, monitoring of regional to global temperature change and changes in the daily temperature range and extremes may use analyzed temperatures. We use the term 'analyses' in the broadest sense to encompass any form of transformation to a regular grid (so from simple gridding through to dynamical reanalyses). Resolution depends on the period and region of the analysis: typically coarser analysis grids correspond to longer periods and larger areas. Some analyses are updated in near-real time.


Femtosecond Second-Harmonic Generation In Periodically Poled Lithium Niobate Waveguides Written By Femtosecond Laser Pulses, Zhangchao Huang, Chenghou Tu, Shuanggen Zhang, Yongnan Li, Fuyun Lu, Yaxian Fan, Enbang Li Jan 2010

Femtosecond Second-Harmonic Generation In Periodically Poled Lithium Niobate Waveguides Written By Femtosecond Laser Pulses, Zhangchao Huang, Chenghou Tu, Shuanggen Zhang, Yongnan Li, Fuyun Lu, Yaxian Fan, Enbang Li

Faculty of Engineering and Information Sciences - Papers: Part A

We present in this Letter the second-harmonic generation of femtosecond pulses in double-line-written waveguides fabricated in periodically poled lithium niobate (PPLN) with femtosecond laser pulses. In a 10-mm-long sample, a normalized conversion efficiency of 12.6% W−1 cm−2 has been achieved for 40 fs pump pulses with the wavelengths centered at 1550 nm. Simulation results show that in PPLN waveguides the FWHM of wavelength tuning curve for 40 fs pump pulses is 42 nm, which is 15 times of that for 40 ps pump pulses.


Compressive Evaluation In Human Motion Tracking, Yifan Lu, Lei Wang, Richard Hartley, Hongdong Li, Dan Xu Jan 2010

Compressive Evaluation In Human Motion Tracking, Yifan Lu, Lei Wang, Richard Hartley, Hongdong Li, Dan Xu

Faculty of Engineering and Information Sciences - Papers: Part A

The powerful theory of compressive sensing enables an efficient way to recover sparse or compressible signals from non-adaptive, sub-Nyquist-rate linear measurements. In particular, it has been shown that random projections can well approximate an isometry, provided that the number of linear measurements is no less than twice of the sparsity level of the signal. Inspired by these, we propose a compressive anneal particle filter to exploit sparsity existing in image-based human motion tracking. Instead of performing full signal recovery, we evaluate the observation likelihood directly in the compressive domain of the observed images. Moreover, we introduce a progressive multilevel wavelet ...


Impacts Of Coal Shrinkage, Permeability And Petrography On Gas Regime In Mines Case Study: Tahmoor Coal Mine, Nsw, Australia, Naj Aziz, Ian Porter, F Sereshki Jan 2010

Impacts Of Coal Shrinkage, Permeability And Petrography On Gas Regime In Mines Case Study: Tahmoor Coal Mine, Nsw, Australia, Naj Aziz, Ian Porter, F Sereshki

Faculty of Engineering and Information Sciences - Papers: Part A

The volumetric changes in the coal matrix (Coal Shrinkage), permeability under various gas environment conditions as well as perographical properties were studied in the laboratory. The shrinkage and permeability of coal were examined with respect to changing gas type and confining pressures. The shrinkage tests were carried out in high-pressure bombs while the permeability study was conducted in a specially constructed high-pressure chamber. Methane (CH4), carbon dioxide (CO2), nitrogen, (N2) and a 50%-50% volume mixture of CO2/CH4 gas were used in the study. The tests showed that under different pressure levels gas type affected permeability and shrinkage characteristics ...


Uniform Regularity In A Wedge And Regularity Of Traces Of Cr Functions, Luca Baracco, Stefano Pinton, Tran Vu Khanh Jan 2010

Uniform Regularity In A Wedge And Regularity Of Traces Of Cr Functions, Luca Baracco, Stefano Pinton, Tran Vu Khanh

Faculty of Engineering and Information Sciences - Papers: Part A

No abstract provided.


Iterative Soft Compensation For Ofdm Systems With Clipping And Superposition Coded Modulation, Jun Tong, Li Ping, Zhonghao Zhang, Vijay Bhargava Jan 2010

Iterative Soft Compensation For Ofdm Systems With Clipping And Superposition Coded Modulation, Jun Tong, Li Ping, Zhonghao Zhang, Vijay Bhargava

Faculty of Engineering and Information Sciences - Papers: Part A

This paper deals with the clipping method used in orthogonal frequency-division multiplexing (OFDM) systems to reduce the peak-to-average power ratio (PAPR). An iterative soft compensation method is proposed to mitigate the clipping distortion, which can outperform conventional treatments. The impact of signaling schemes on the residual clipping noise power is studied via the symbol variance analysis. It is found that superposition coded modulation (SCM) can minimize the residual clipping noise power among all possible signaling schemes. This indicates that SCM-based OFDM systems are more robust to clipping effect than other alternatives when soft compensation is applied. It is also shown ...


High-Energy, Khz-Repetition-Rate, Ps Cryogenic Yb:Yag Chirped-Pulse Amplifier, Kyung-Han Hong, Juliet Gopinath, Darren Rand, Aleem M. Siddiqui, Shu-Wei Huang, Enbang Li, Benjamin J. Eggleton, John D. Hybl, Tso Yee Fan, Franz X. Kartner Jan 2010

High-Energy, Khz-Repetition-Rate, Ps Cryogenic Yb:Yag Chirped-Pulse Amplifier, Kyung-Han Hong, Juliet Gopinath, Darren Rand, Aleem M. Siddiqui, Shu-Wei Huang, Enbang Li, Benjamin J. Eggleton, John D. Hybl, Tso Yee Fan, Franz X. Kartner

Faculty of Engineering and Information Sciences - Papers: Part A

We demonstrate amplification of picosecond laser pulses to 40 mJ at a 2 kHz pulse repetition frequency (PRF) from a two-stage cryogenic chirped-pulse Yb:YAG amplifier, composed of a regenerative amplifier (RGA) and a two-pass booster amplifier. The RGA produces 8.2 mJ of energy at 2 kHz PRF and 13.2 mJ at 1 kHz PRF with excellent energy stability (~0.3% rms) and beam quality ( M2<1.1 ). Pulse stretching and compression are achieved by using a chirped fiber Bragg grating and a multilayer dielectric grating pair, respectively. Compressed 15 ps pulses from the RGA are obtained with a throughput efficiency of ~80% (~6.5 mJ for 2 kHz ). The booster amplifier further amplifies the pulses to 40 mJ at 2 kHz PRF, and ~32 mJ, ~15 ps pulses are expected after compression. The amplifier chain seeded from a femtosecond Yb-fiber laser enables the optical self-synchronization between signal and pump in optical parametric chirped-pulse amplifier applications.


Mechanical Property Development During Uoe Forming Of Large Diameter Pipeline Steels, Andrii Kostryzhev, Martin Strangwood, Claire L. Davis Jan 2010

Mechanical Property Development During Uoe Forming Of Large Diameter Pipeline Steels, Andrii Kostryzhev, Martin Strangwood, Claire L. Davis

Faculty of Engineering and Information Sciences - Papers: Part A

Mechanical properties of large diameter welded steel pipes depend on the thermomechanically controlled rolled (TMCR) plate microstructure and UOE pipe-forming cold deformation sequence. Strength from plate to pipe may increase (work-hardening) or decrease (the Bauschinger effect). Bauschinger effect parameters depend on steel composition and plate processing history. The present study is examining two pipeline grades: X60 (Nb-alloyed) and X65 (Nb- and V-alloyed). Mechanical properties are determined by grain refinement, solid solution, precipitation strengthening mechanisms, and work-hardening (work-softening). The reverse deformation yield drop increases with an increase in the precipitate particle volume fraction and pre-strain. Annealing, leading to a decrease in ...


The Impact Of Strategy And Maturity On Business Analytics And Firm Performance: A Review And Research Agenda, Graeme Shanks, Rajeev Sharma, Peter Seddon, Peter Reynolds Jan 2010

The Impact Of Strategy And Maturity On Business Analytics And Firm Performance: A Review And Research Agenda, Graeme Shanks, Rajeev Sharma, Peter Seddon, Peter Reynolds

Faculty of Engineering and Information Sciences - Papers: Part A

Business analytics involves interpreting organizational data to improve decision-making and to optimise business processes. It has the potential to improve firm performance and increase competitive advantage. Although many case studies have been reponed that describe business analytics applications and speculate about how they might contribute to firm performance, there is no clearly articulated and theoretically grounded model in the literature. This paper proposes a theoretical framework jor understanding how and why business analytics technology and capabilities can lead to value-creating actions that lead to improved form performance and competitive advantage. We jocus particularly on how strategy and maturity impact business ...