Search results

1 – 10 of over 32000
Book part
Publication date: 15 April 2020

Yubo Tao and Jun Yu

This chapter examines the limit properties of information criteria (such as AIC, BIC, and HQIC) for distinguishing between the unit-root (UR) model and the various kinds of…

Abstract

This chapter examines the limit properties of information criteria (such as AIC, BIC, and HQIC) for distinguishing between the unit-root (UR) model and the various kinds of explosive models. The explosive models include the local-to-unit-root model from the explosive side the mildly explosive (ME) model, and the regular explosive model. Initial conditions with different orders of magnitude are considered. Both the OLS estimator and the indirect inference estimator are studied. It is found that BIC and HQIC, but not AIC, consistently select the UR model when data come from the UR model. When data come from the local-to-unit-root model from the explosive side, both BIC and HQIC select the wrong model with probability approaching 1 while AIC has a positive probability of selecting the right model in the limit. When data come from the regular explosive model or from the ME model in the form of 1 + nα/n with α ∈ (0, 1), all three information criteria consistently select the true model. Indirect inference estimation can increase or decrease the probability for information criteria to select the right model asymptotically relative to OLS, depending on the information criteria and the true model. Simulation results confirm our asymptotic results in finite sample.

Article
Publication date: 1 March 2004

A.B. Yu

Discrete element method (DEM) has been extensively used in the laboratory of particulate and multiphase processing at the University of New South Wales (UNSW) to study the…

2933

Abstract

Discrete element method (DEM) has been extensively used in the laboratory of particulate and multiphase processing at the University of New South Wales (UNSW) to study the fundamentals of particulate matter at a particle scale. This paper briefly reviews the work in the laboratory, which covers the development of simulation techniques and their application to the study of particle packing and flow, transport properties and constitutive relationships of typical static or dynamic particulate systems. It is concluded, through representative comparison between simulated and measured results under different conditions, that DEM, as a major technique for discrete particle simulation, is an effective method for particle scale research of particulate matter.

Details

Engineering Computations, vol. 21 no. 2/3/4
Type: Research Article
ISSN: 0264-4401

Keywords

Book part
Publication date: 15 March 2022

Chung-Gee Lin, Min-Teh Yu, Chien-Yu Chen and Pei-Hsuan Hsu

This chapter derives sentiment indicators (implied volatility and implied skewness) from the option pricing models of Corrado and Su (1996), Bakshi, Kapadia, and Madan (2003), and…

Abstract

This chapter derives sentiment indicators (implied volatility and implied skewness) from the option pricing models of Corrado and Su (1996), Bakshi, Kapadia, and Madan (2003), and Zhang, Zhen, Sun, and Zhao (2017), and then integrates these sentiment indicators with artificial intelligence deep neural network (AIDNN) for developing the behavioral finance AIDNN (BFAIDNN) algorithms. We apply the BFAIDNN algorithms to daily derivatives data of Taiwan Futures and Options markets from 2015 to 2017. Our results demonstrate that the trading strategies established by the BFAIDNN algorithms can generate positive rewards.

Details

Advances in Pacific Basin Business, Economics and Finance
Type: Book
ISBN: 978-1-80117-313-1

Keywords

Article
Publication date: 7 May 2024

Tian-Yu Wu, Jianfei Zhang, Yanjun Dai, Tao-Feng Cao, Kong Ling and Wen-Quan Tao

To present the detailed implementation processes of the IDEAL algorithm for two-dimensional compressible flows based on Delaunay triangular mesh, and compare the performance of…

Abstract

Purpose

To present the detailed implementation processes of the IDEAL algorithm for two-dimensional compressible flows based on Delaunay triangular mesh, and compare the performance of the SIMPLE and IDEAL algorithms for solving compressible problems. What’s more, the implementation processes of Delaunay mesh generation and derivation of the pressure correction equation are also introduced.

Design/methodology/approach

Programming completely in C++.

Findings

Five compressible examples are used to test the SIMPLE and IDEAL algorithms, and the comparison with measurement data shows good agreement. The IDEAL algorithm has much better performance in both convergence rate and stability over the SIMPLE algorithm.

Originality/value

The detail solution procedure of implementing the IDEAL algorithm for compressible flows based on Delaunay triangular mesh is presented in this work, seemingly first in the literature.

Details

Engineering Computations, vol. 41 no. 3
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 3 April 2023

Kangkang Yu, Jack Cadeaux, Ben Nanfeng Luo and Cheng Qian

This study aims to extend ambidexterity theory from the perspective of organisational learning and examine how process ambidexterity, which comprises operational flexibility and…

Abstract

Purpose

This study aims to extend ambidexterity theory from the perspective of organisational learning and examine how process ambidexterity, which comprises operational flexibility and operational routine, responds to environmental uncertainty and ultimately reduces organisational risks.

Design/methodology/approach

This study tests the hypotheses by analysing 464 annual reports of 115 listed companies in the Chinese agricultural and food industry using content and secondary data analyses. Four case studies are also provided.

Findings

The results show that (1) environmental uncertainty has a positive effect on either operational flexibility or operational routine; (2) both operational flexibility and operational routine have negative effects on organisational risks, supporting the view that process ambidexterity mediates the relationship between environmental uncertainty and organisational risks; and (3) organisational slack plays the role of “double-edged sword” by negatively moderating the effect of environmental uncertainty on operational flexibility and positively moderating the effect of environmental uncertainty on operational routine.

Originality/value

In an uncertain environment, companies are exposed to greater risk. This study contributes to risk management in three ways: first, it extends ambidexterity theory to process management and proposes how process ambidexterity balances operational flexibility and routines. Second, it distinguishes between the different conditions under which flexibility or routines are superior. Third, it explains the mechanisms related to how organisations can resolve environmental uncertainty into risk through process ambidexterity.

Details

International Journal of Operations & Production Management, vol. 43 no. 12
Type: Research Article
ISSN: 0144-3577

Keywords

Article
Publication date: 13 September 2023

Dong-Jin Lee, Grace B. Yu and M. Joseph Sirgy

The purpose of this paper is to reflect on the construct of phygital experiences and provide ideas that may spur future research on phygital consumer experiences in relation to…

Abstract

Purpose

The purpose of this paper is to reflect on the construct of phygital experiences and provide ideas that may spur future research on phygital consumer experiences in relation to consumer well-being using qualitative research methods.

Design/methodology/approach

With the increase in consumers’ online and offline interactions, there is a greater need for marketers to prompt integrated consumer experiences (i.e. integrated customer experiences through online and offline interactions). The authors developed this essay based on a literature review of phygital experiences and consumer well-being.

Findings

This commentary provides suggestions on how to expand the conceptual boundaries of phygital experiences by examining the effects of consumer phygital experiences in relation to consumer need satisfaction, consumer happiness and benefits to the firm. The commentary also includes several methodological suggestions that can guide future qualitative research.

Originality/value

The value of this commentary involves insights about research methods stimulated by the current research on consumer well-being.

Details

Qualitative Market Research: An International Journal, vol. 27 no. 3
Type: Research Article
ISSN: 1352-2752

Keywords

Article
Publication date: 11 December 2019

Zhangyu Wu, Hongfa Yu, Haiyan Ma, Bo Da and Yongshan Tan

Coral aggregate seawater concrete (CASC) is a new type of lightweight aggregate concrete that is becoming widely used in reef engineering. To investigate the corrosion behavior of…

Abstract

Purpose

Coral aggregate seawater concrete (CASC) is a new type of lightweight aggregate concrete that is becoming widely used in reef engineering. To investigate the corrosion behavior of different kinds of rebar in CASC exposed to simulated seawater for 0-270 d, the electrochemical techniques, including linear polarization resistance (LPR) technique and the electrochemical impedance spectroscopy (EIS), were used in the present work.

Design/methodology/approach

The electrochemical techniques, including LPR technique and the EIS, were used in the present work.

Findings

Based on the time-varying law of linear polarization curves, self-corrosion potential (Ecorr), polarization resistance (Rp), corrosion current density (Icorr), corrosion rate (i), and the characteristics of EIS diagrams for different types of rebar in CASC, it can be found that the anti-corrosion property of them can be ranked as epoxy resin coated steel > 2205 duplex stainless steel (2205S) > 316 L stainless steel (316 L) > organic coated steel > ordinary steel. Additionally, the linear regression equation between Rp and charge transfer resistance (Rct) was established. Finally, the EIS corrosion standard of rebar was established from the LPR corrosion standard, which provides a direct standard for the EIS technique to determine the condition of rebar in CASC.

Originality/value

The linear regression equation between polarization resistance and charge transfer resistance was established. And the EIS corrosion standard of rebar was established from the LPR corrosion standard, which provides a direct standard for the EIS technique to determine the condition of rebar in CASC.

Details

Anti-Corrosion Methods and Materials, vol. 67 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 10 July 2023

Qian Wang, Biao Ma, Liang Yu, Man Chen, Guoyu Wang and Liangjie Zheng

This paper aims to explore the influence of applied pressure on the tribological properties of the friction component in a wet multi-disc clutch during the running-in process.

Abstract

Purpose

This paper aims to explore the influence of applied pressure on the tribological properties of the friction component in a wet multi-disc clutch during the running-in process.

Design/methodology/approach

The running-in evolutionary was explored in terms of global friction performance. The variation of friction torque and mean COF of the initial 300 engagement cycles was obtained by full-scale tests. Finally, an optical microscope was used to detect the wear characteristics of friction surfaces.

Findings

The applied pressure showed a significant influence on the tribological behaviors of wet clutches during the running-in process. The mean COF decreased and then increases with the increase of the applied pressure. A higher applied pressure contributed to more asperity summits being sheared, thus resulting in a smoother surface. Considering a suitable wore performance, properly applied pressure is necessary.

Originality/value

The results provide theoretical guidance for selecting the optimal applied pressure in the running-in of wet clutches.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2022-0256/

Details

Industrial Lubrication and Tribology, vol. 75 no. 6
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 1 February 1981

B.G. Avetikov, A.N. Tsvetkov and Ye. I. Yurevich

Flexible assembly systems in any part of the world are still rare. From the USSR is a report of a machine that is working and saving money. Using industrial robots and an adaptive…

Abstract

Flexible assembly systems in any part of the world are still rare. From the USSR is a report of a machine that is working and saving money. Using industrial robots and an adaptive control system 39 operators have been replaced in 3 shift working. A variety of products can be assembled on the one machine with only a need to switch grippers and some auxiliaries on changeover.

Details

Assembly Automation, vol. 1 no. 2
Type: Research Article
ISSN: 0144-5154

Article
Publication date: 25 April 2022

Zhao-Qin Wang, Yu Shi and Xiao-Rong Wang

The bisection inverse search bow height control interpolation (BIS-BHCI) method for nonuniform rational B-splines (NURBS) curve is proposed to accomplish the serial robotic plasma…

Abstract

Purpose

The bisection inverse search bow height control interpolation (BIS-BHCI) method for nonuniform rational B-splines (NURBS) curve is proposed to accomplish the serial robotic plasma cladding of planar complex curve coating with high precision.

Design/methodology/approach

A plasma–computer integrated cladding system is constructed based on a Motoman-UP6 serial robot and a plasma power. Based on the BIS-BHCI method, combining the serial robotic kinematics with the NURBS curve model, an offline plasma cladding software is developed for Motoman-UP6. Before plasma cladding, a planar NURBS curve coating is designed and defined and its BIS-BHCI is carried out with proper parameters. Then, the cladding programs are generated using the BIS-BHCI results and the robotic kinematics and inputted into the serial robotic controller. After that, the plasma cladding of the planar NURBS curve coating is implemented based on the Motoman-UP6 serial robot.

Findings

The simulation and plasma cladding for the NURBS curve coating shows that the BIS-BHCI method is feasible and effective. Plasma cladding of complex NURBS curve coating based on serial robot is feasible and effective.

Originality/value

The complex NURBS curve coating is prepared based on a serial robot platform for the first time. It provides a theoretical and technical basis for plasma cladding to produce surface coatings of industrial complex parts. With the increasing application of complex parts, the plasma cladding process of complex NURBS curve coatings has a broad application prospect.

Details

Industrial Robot: the international journal of robotics research and application, vol. 49 no. 6
Type: Research Article
ISSN: 0143-991X

Keywords

1 – 10 of over 32000