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Article
Publication date: 28 August 2024

Jingxuan Chai, Jie Mei, Youmin Gong, Weiren Wu, Guangfu Ma and Guoming Zhao

Asteroids have the characteristics of noncooperative, irregular gravity and complex terrain on the surface, which cause difficulties in successful landing for conventional…

55

Abstract

Purpose

Asteroids have the characteristics of noncooperative, irregular gravity and complex terrain on the surface, which cause difficulties in successful landing for conventional landers. The purpose of this paper is to study the trajectory tracking problem of a multi-node flexible lander with unknown flexible coefficient and space disturbance.

Design/methodology/approach

To facilitate the stability analysis, this paper constructs a simplified dynamic model of the multi-node flexible lander. By introducing the nonlinear transformation, a concurrent learning-based adaptive trajectory tracking guidance law is designed to ensure tracking performance, which uses both real-time information and historical data to estimate the parameters without persistent excitation (PE) conditions. A data selection algorithm is developed to enhance the richness of historical data, which can improve the convergence rate of the parameter estimation and the guidance performance.

Findings

Finally, Lyapunov stability theory is used to prove that the unknown parameters can converge to their actual value and, meanwhile, the closed-loop system is stable. The effectiveness of the proposed algorithm is further verified through simulations.

Originality/value

This paper provides a new design idea for future asteroid landers, and a trajectory tracking controller based on concurrent learning and preset performance is first proposed.

Details

Aircraft Engineering and Aerospace Technology, vol. 96 no. 9
Type: Research Article
ISSN: 1748-8842

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Article
Publication date: 9 August 2022

Chunyun Zhang, Jie Mei, Yushuai Bai, Miao Cui, Haifeng Peng and X. W. Gao

The purpose of this study is to simultaneously determine the constitutive parameters and boundary conditions by solving inverse mechanical problems of power hardening…

133

Abstract

Purpose

The purpose of this study is to simultaneously determine the constitutive parameters and boundary conditions by solving inverse mechanical problems of power hardening elastoplastic materials in three-dimensional geometries.

Design/methodology/approach

The power hardening elastoplastic problem is solved by the complex variable finite element method in software ABAQUS, based on a three-dimensional complex stress element using user-defined element subroutine. The complex-variable-differentiation method is introduced and used to accurately calculate the sensitivity coefficients in the multiple parameters identification method, and the Levenberg–Marquardt algorithm is applied to carry out the inversion.

Findings

Numerical results indicate that the complex variable finite element method has good performance for solving elastoplastic problems of three-dimensional geometries. The inversion method is effective and accurate for simultaneously identifying multi-parameters of power hardening elastoplastic problems in three-dimensional geometries, which could be employed for solving inverse elastoplastic problems in engineering applications.

Originality/value

The constitutive parameters and boundary conditions are simultaneously identified for power hardening elastoplastic problems in three-dimensional geometries, which is much challenging in practical applications. The numerical results show that the inversion method has high accuracy, good stability, and fast convergence speed.

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Article
Publication date: 3 May 2016

Changqing Miao, Jie Yu and Mingxing Mei

This paper aims to research steel wire corrosion pitting distribution characteristics and evolution, the shape, number and size of corrosion pits from one tied arch bridge were…

279

Abstract

Purpose

This paper aims to research steel wire corrosion pitting distribution characteristics and evolution, the shape, number and size of corrosion pits from one tied arch bridge were tested, analyzed and researched.

Design/methodology/approach

The probability distribution model of corrosion pits of different shapes was established, and the law of corrosion pit growth and evolution was researched. The relationship between the steel wire local corrosion parameters and the average degree of corrosion was explored.

Findings

The results revealed that the pits of steel wires can be divided into four categories of shapes: a deep ellipsoidal shape, a shallow ellipsoidal shape, a groove shape and a saddle shape. When developing to a certain degree, the small dark narrow type corrosion pit will turn into a large open pit of either a shallow ellipsoidal shape, a groove shape or a saddle shape.

Originality/value

The maximum depth of the corrosion pits was close to the Weibull distribution, and the maximum width and length of the wire corrosion pits were close to the logarithmic normal distribution, causing a large error when using a uniform corrosion model of steel wire mechanics.

Details

Anti-Corrosion Methods and Materials, vol. 63 no. 3
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 23 September 2024

FaGuang Jiang, Kebing Chen, Yang Chen and Cheng Tian

In response to the challenges posed by the conventional manual flange docking method in the LNG (Liquefied Natural Gas) loading process, such as low positioning accuracy…

41

Abstract

Purpose

In response to the challenges posed by the conventional manual flange docking method in the LNG (Liquefied Natural Gas) loading process, such as low positioning accuracy, constraints on production efficiency and safety hazards, this study analyzed the LNG five-axis loading arm’s main functions and structural characteristics.

Design/methodology/approach

An automated solution for the joints of the LNG loading arm was designed. The forward kinematic model of the LNG loading arm was established using the Denavit–Hartenberg (D-H) parameter method, and its workspace was analyzed. The Newton–Raphson iteration method was employed to solve the inverse kinematics of the LNG loading arm, facilitating trajectory planning. The relationship between the target position and the joint variables was established to verify the stability of the arm’s motion. Flange center identification was achieved using the Hough transform function. Based on the ROS platform, combined with Gazebo and Rviz, an experimental simulation of automatic docking of the LNG loading arm was conducted.

Findings

The docking errors in the XYZ directions were all less than 0.8 mm, meeting the required docking accuracy. Moreover, the motion performance of the loading arm during docking was smooth and free of abrupt changes, validating its capability to accomplish the automatic docking task.

Originality/value

The proposed trajectory planning and automatic docking scheme can be used for the rapid filling of LNG filling arms and LNG tankers to improve the efficiency of LNG transportation. In guiding the docking, the proposed automatic docking scheme is an accurate and efficient way to improve safety.

Details

Engineering Computations, vol. 41 no. 8/9
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 26 November 2019

Le Wang, Hai-Hua Hu, Jie Yan and Maggie Qiuzhu Mei

The purpose of this paper is to explore the antecedents of self-disclosure intention on mobile social applications. This study integrates privacy calculus model and elaboration…

1625

Abstract

Purpose

The purpose of this paper is to explore the antecedents of self-disclosure intention on mobile social applications. This study integrates privacy calculus model and elaboration likelihood theory to reconcile the rational and heuristic views of privacy decision making.

Design/methodology/approach

Using a “random dialing” sampling method, an empirical survey with 913 respondents was conducted. A series of regression models were employed to test the proposed relationships. Robust checks with sub-group analysis were conducted.

Findings

Self-disclosure intention develops along a dual route including the central route and the peripheral route. When the central route predominates, social media users form their attitudes toward self-disclosure based on a rational calculus of the privacy concern and perceived rewards. When the peripheral route predominates, users perform a more heuristic evaluation of relevant informational cues (information about privacy harms, the extent of information asymmetry between users and operators) and contextual cues (flow experience, privacy disclosure of friends). Peripheral cues moderate the relationships between central cues and self-disclosure intention.

Originality/value

This paper extends the Elaboration Likelihood Model by investigating the interaction between the central route and peripheral route. The results provide alternative explanations on the renowned “privacy paradox” phenomenon.

Details

Journal of Enterprise Information Management, vol. 33 no. 2
Type: Research Article
ISSN: 1741-0398

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Article
Publication date: 22 November 2018

Jie Liang and Nan Mei

The purpose of this paper is to examine the following research question in partner selection decisions in business-to-business strategic partnerships/collaborations literature…

587

Abstract

Purpose

The purpose of this paper is to examine the following research question in partner selection decisions in business-to-business strategic partnerships/collaborations literature: How do inertia and uncertainty affect partner selection? Explicitly, the paper analyzes how inertia of previous alliance selection routines and uncertainty of entire market movement shape firms’ preferences regarding exploratory partner selection (i.e. selecting new partners who never collaborate with the focal firm).

Design/methodology/approach

Grounded on inter-firm partnerships, partner selection and network theory literature, the study empirically tests a fine-grained sample of 511 open-end funds initiated by 61 fund management firms in China. To do so, it runs Tobit regression for main analysis and applies a variety of sensitivity analyses to check the robustness.

Findings

Results show that inertia in previous partner selection has a negative effect on exploration. Importantly, these inertial forces impact domestic firms but not international firms. Market uncertainty also affects exploratory partner selection: short-term market uncertainty encourages exploration, whereas long-term uncertainty inhibits it. These effects also depend on firms’ type: long-term market uncertainty has a negative effect on exploration for international firms but not for domestic firms. Both types of firms exhibit a stronger tendency toward exploration when they encounter short-term uncertainty. However, this inclination is stronger in international firms.

Originality/value

Earlier research has examined how inertia affects exploitation but largely overlooked its effect on exploration. A critical examination of firm and environment level factors provides a deeper understanding of why and when firms have inconsistent preferences for specific partner selection strategies. Thus, this study offers a unique perspective for understanding firms’ exploratory partner selection by focusing on two important characteristics of focal firms: one internal (inertia) and one external (market uncertainty) in nature.

Details

Journal of Business & Industrial Marketing, vol. 34 no. 6
Type: Research Article
ISSN: 0885-8624

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Article
Publication date: 25 June 2019

Mei Cai, Guo Wei and Jie Cao

This paper aims to demonstrate how to make emergency decision when decision makers face a complex and turbulent environment that needs quite different decision-making processes…

234

Abstract

Purpose

This paper aims to demonstrate how to make emergency decision when decision makers face a complex and turbulent environment that needs quite different decision-making processes from conventional ones. Traditional decision techniques cannot meet the demands of today’s social stability and security.

Design/methodology/approach

The main work is to develop an instance-driven classifier for the emergency categories based upon three fuzzy measures: features for an instance, solution for the instance and effect evaluation of the outcome. First, the information collected from the past emergency events is encodes into a prototype model. Second, a three-dimensional space that describes the locations and mutual distance relationships of the emergency events in different emergency prototypes is formulated. Third, for any new emergency event to be classified, the nearest emergency prototype is identified in the three-dimensional space and is classified into that category.

Findings

An instance-driven classifier based on prototype theory helps decision makers to describe emergency concept more clearly. The maximizing deviation model is constructed to determine the optimal relative weights of features according to the characteristics of the new instance, such that every customized feature space maximizes the influence of features shared by members of the category. Comparisons and discusses of the proposed method with other existing methods are given.

Practical implications

To reduce the affection to economic development, more and more countries have recognized the importance of emergency response solutions as an indispensable activity. In a new emergency instance, it is very challengeable for a decision maker to form a rational and feasible humanitarian aids scheme under the time pressure. After selecting a most suitable prototype, decision makers can learn most relevant experience and lessons in the emergency profile database and generate plan for the new instance. The proposed approach is to effectively make full use of inhomogeneous information in different types of resources and optimize resource allocation.

Originality/value

The combination of instances can reflect different aspects of a prototype. This feature solves the problem of insufficient learning data, which is a significant characteristic of emergency decision-making. It can be seen as a customized classification mechanism, while the previous classifiers always assume key features of a category.

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Article
Publication date: 4 May 2023

Yi-Yun Cheng and Yilin Xia

The purpose of this study is to provide a systematic literature review on taxonomy alignment methods in information science to explore the common research pipeline and…

263

Abstract

Purpose

The purpose of this study is to provide a systematic literature review on taxonomy alignment methods in information science to explore the common research pipeline and characteristics.

Design/methodology/approach

The authors implement a five-step systematic literature review process relating to taxonomy alignment. They take on a knowledge organization system (KOS) perspective, and specifically examining the level of KOS on “taxonomies.”

Findings

They synthesize the matching dimensions of 28 taxonomy alignment studies in terms of the taxonomy input, approach and output. In the input dimension, they develop three characteristics: tree shapes, variable names and symmetry; for approach: methodology, unit of matching, comparison type and relation type; for output: the number of merged solutions and whether original taxonomies are preserved in the solutions.

Research limitations/implications

The main research implications of this study are threefold: (1) to enhance the understanding of the characteristics of a taxonomy alignment work; (2) to provide a novel categorization of taxonomy alignment approaches into natural language processing approach, logic-based approach and heuristic-based approach; (3) to provide a methodological guideline on the must-include characteristics for future taxonomy alignment research.

Originality/value

There is no existing comprehensive review on the alignment of “taxonomies”. Further, no other mapping survey research has discussed the comparison from a KOS perspective. Using a KOS lens is critical in understanding the broader picture of what other similar systems of organizations are, and enables us to define taxonomies more precisely.

Details

Journal of Documentation, vol. 79 no. 6
Type: Research Article
ISSN: 0022-0418

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Article
Publication date: 26 April 2013

T.S. Dhahi, U. Hashim and M.E. Ali

The purpose of this paper was to systematically study the electrical properties of 5‐, 42‐ and 75‐nm gap polysilicon structures to evaluate the potentiality of these structures to…

124

Abstract

Purpose

The purpose of this paper was to systematically study the electrical properties of 5‐, 42‐ and 75‐nm gap polysilicon structures to evaluate the potentiality of these structures to be used in biomolecular sensing devices.

Design/methodology/approach

The authors previously reported the fabrication and morphological characterization of these structures. In this report, they electrically probed the presence of nanogap through current measurement. The effects of electrolytes on the capacitance profiles of these structures were systematically studied with air, water and various dilutions of phosphate buffer saline.

Findings

An increment in capacitance was found with the increment in electrolyte concentration. Improvement in current flow, capacitance, permittivity, and conductivity were observed with the smaller size nanogaps, suggesting their applications in low power consuming devices.

Originality/value

Since nanogap‐based dielectric biosensing devices need to be operated with a low level of current to avoid biomolecular damage, these structures should have potential applications in dielectric‐based biomolecular detection using a low cost dielectric analyser.

Details

Microelectronics International, vol. 30 no. 2
Type: Research Article
ISSN: 1356-5362

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Book part
Publication date: 7 December 2023

Mikael Johnsson

It is suggested that, to be successful, innovation teams should be small and consist of people with key expertise who want to participate and develop new solutions within their…

Abstract

It is suggested that, to be successful, innovation teams should be small and consist of people with key expertise who want to participate and develop new solutions within their organisations. When it comes to conducting innovation work, I suggest shared leadership may be a factor influencing success. In this chapter, a theoretical framework is presented on the shared leadership of innovation teams. The key to establishing shared leadership in innovation teams is to plan for it as the team is created, not after the team has already been formed, as this may result in various problems in the intended innovation project. The proposed framework details key aspects to consider; some of which are related to external factors such as management and resources, and some to internal factors such as the team’s size, competencies, and their ability to develop norms and ways of working together. The proposed framework is applicable for managers, innovation leaders, and team members, and contributes to previous research on shared leadership and innovation leadership. Further research on the proposed framework is suggested.

Details

Innovation Leadership in Practice: How Leaders Turn Ideas into Value in a Changing World
Type: Book
ISBN: 978-1-83753-397-8

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