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Article

Qiao Qiao, Jianping Yuan and Xin Ning

The purpose of this paper is to establish the dynamics model of a Z-folded PhoneSat considering hinge friction and to investigate the influence of disturbances, such as…

Abstract

Purpose

The purpose of this paper is to establish the dynamics model of a Z-folded PhoneSat considering hinge friction and to investigate the influence of disturbances, such as friction, stiffness asymmetry, deployment asynchronicity and initial disturbance angular velocity, on the attitude of PhoneSat during and after deployment.

Design/methodology/approach

For the Z-folded PhoneSat, the dynamics model considering hinge friction is established and the dynamics simulation is carried out. The effects of friction, stiffness asymmetry, deployment asynchronicity and initial disturbance angular velocity on the attitude motion of the PhoneSat are studied and the attitude motion regularities of the PhoneSat considering the disturbance factors mentioned above are discussed.

Findings

Friction has a main contribution to reducing the oscillation of attitude motion and damping out the residual oscillation, ultimately decreasing the deployment time. An increasing length of deployment time is required with the increasing stiffness asymmetry and time difference of asynchronous deployment, which also have slight disturbances on the attitude angle and angular velocity of PhoneSat after the deployment. The initial disturbance angular velocity in the direction of deployment would be proportionally weakened after the deployment, whereas initial disturbance angular velocity in other direction induces angular velocities of other axes, which dramatically enhances the complexity of attitude control.

Originality/value

The paper is a useful reference for engineering design of small satellites attitude control system.

Details

Aircraft Engineering and Aerospace Technology, vol. 89 no. 3
Type: Research Article
ISSN: 1748-8842

Keywords

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Article

Junhua Zhang, Jianping Yuan, Wei Wang and Jiao Wang

The purpose of this paper is to obtain the reachable domain (RD) for spacecraft with a single normal impulse while considering both time and impulse constraints.

Abstract

Purpose

The purpose of this paper is to obtain the reachable domain (RD) for spacecraft with a single normal impulse while considering both time and impulse constraints.

Design/methodology/approach

The problem of RD is addressed in an analytical approach by analyzing for either the initial maneuver point or the impulse magnitude being arbitrary. The trajectories are considered lying in the intersection of a plane and an ellipsoid of revolution, whose family can be determined analytically. Moreover, the impulse and time constraints are considered while formulating the problem. The upper bound of impulse magnitude, “high consumption areas” and the change of semi-major axis and eccentricity are discussed.

Findings

The equations of RD with a single normal impulse are analytically obtained. The equations of three scenarios are obtained. If normal impulse is too large, the RD cannot be obtained. The change of the semi-major axis and eccentricity with large normal impulse is more obvious. For long-term missions, the change of semi-major axis and eccentricity leaded by multiple normal impulses should be considered.

Practical implications

The RD gives the pre-defined region (all positions accessible) for a spacecraft under a given initial orbit and a normal impulse with certain magnitude.

Originality/value

The RD for spacecraft with normal impulse can be used for non-coplanar orbital transfers, emergency evacuation after failure of rendezvous and docking and collision avoidance.

Details

Aircraft Engineering and Aerospace Technology, vol. 91 no. 7
Type: Research Article
ISSN: 1748-8842

Keywords

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Article

Yuan Ping, Haiyan Su, Jianping Zhao and Xinlong Feng

This paper aims to propose two parallel two-step finite element algorithms based on fully overlapping domain decomposition for solving the 2D/3D time-dependent natural…

Abstract

Purpose

This paper aims to propose two parallel two-step finite element algorithms based on fully overlapping domain decomposition for solving the 2D/3D time-dependent natural convection problem.

Design/methodology/approach

The first-order implicit Euler formula and second-order Crank–Nicolson formula are used to time discretization respectively. Each processor of the algorithms computes a stabilized solution in its own global composite mesh in parallel. These algorithms compute a nonlinear system for the velocity, pressure and temperature based on a lower-order element pair (P1b-P1-P1) and solve a linear approximation based on a higher-order element pair (P2-P1-P2) on the same mesh, which shows that the new algorithms have the same convergence rate as the two-step finite element methods. What is more, the stability analysis of the proposed algorithms is derived. Finally, numerical experiments are presented to demonstrate the efficacy and accuracy of the proposed algorithms.

Findings

Finally, numerical experiments are presented to demonstrate the efficacy and accuracy of the proposed algorithms.

Originality/value

The novel parallel two-step algorithms for incompressible natural convection problem are proposed. The rigorous analysis of the stability is given for the proposed parallel two-step algorithms. Extensive 2D/3D numerical tests demonstrate that the parallel two-step algorithms can deal with the incompressible natural convection problem for high Rayleigh number well.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 2
Type: Research Article
ISSN: 0961-5539

Keywords

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Article

Chen Jianping and Yang Zhongwei

The purpose of this paper is to examine the extent to which financial privacy is present and necessary in dealings between banks and clients in China.

Abstract

Purpose

The purpose of this paper is to examine the extent to which financial privacy is present and necessary in dealings between banks and clients in China.

Design/methodology/approach

This paper provides a comparative study drawing, in particular, on developments in the USA.

Findings

It is a trend in legislation in the western developed countries that the right to privacy is taken seriously and private information in the financial activities is protected by law. The legislation in the USA is typically systematic and complete. The fact that financial privacy protection is sparsely stipulated in finance or administrative laws but the protection of privacy has yet not been systematically written into law in China so far, which is inconsistent with the current situations of the financial industry. China should deal with the relationship between banks and clients, administrative power and personal rights, judicial interpretation and legislation from the aspect of financial practice, so as to set up the legal system to protect financial privacy by learning from the legislation in the USA based on the national conditions.

Originality/value

The paper provides a systematic view of the value of financial privacy in the modern world, with recommendations for reform in China.

Details

International Journal of Law and Management, vol. 51 no. 4
Type: Research Article
ISSN: 1754-243X

Keywords

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Book part

Jianping Shen and Van E.

In this chapter we discuss the content and process of the Learning-Centered Leadership Development Program for Practicing and Aspiring Principals. In terms of the content…

Abstract

In this chapter we discuss the content and process of the Learning-Centered Leadership Development Program for Practicing and Aspiring Principals. In terms of the content, based on extensive literature review the program focuses on seven dimensions of principal leadership associated with student achievement. In terms of process, one pair of practicing and aspiring principals from each school engage in five levels of learning – moving from (a) experiential, to (b) declarative, to (c) procedural, to (d) contextual, and to (e) evidential. The pair of practicing and aspiring principals works with two additional teacher leaders to develop sufficient leadership density in the school to plan and implement renewal activities along the seven dimensions to improve student achievement. We also reflect upon the lessons learned from implementing the program.

Details

Successful School Leadership Preparation and Development
Type: Book
ISBN: 978-1-78052-322-4

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Article

Wang Haisu and Fang Zhongxiu

The paper aims to examine the similarities of fast‐growth private enterprises (PEs) in China with particular focus on enterprises listed on growth enterprises market in…

Abstract

Purpose

The paper aims to examine the similarities of fast‐growth private enterprises (PEs) in China with particular focus on enterprises listed on growth enterprises market in order to draw managerial implications for other PEs.

Design/methodology/approach

The paper looks at the release effects of intangible assets in PEs. It examines the excavation effects of preferential policy on PEs and goes on to discuss the agglomeration effects of the inherent advantages of these.

Findings

The paper argues that the fast growth of PEs in our sample was attributable to three main factors, i.e. benefits of intangible assets marketisation, shrewd use of government preferential policies and technological and managerial capabilities.

Practical implications

This research calls for the Chinese Government to adjust relevant policies to create a fair and competitive environment for enterprises with different ownerships and different scales.

Originality/value

The paper highlights the fact that the social and economic conditions of China in the post‐transition period have changed greatly and that the Chinese Government needs to clarify and define the existing characteristics and functions of enterprises and improve their service‐oriented functions.

Details

Journal of Chinese Entrepreneurship, vol. 2 no. 3
Type: Research Article
ISSN: 1756-1396

Keywords

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Article

Pengpeng Cheng, Daoling Chen and Jianping Wang

For comfort evaluation of underwear pressure, this paper proposes an improved GA algorithm to optimize the weight and threshold of BP neural network, namely PSO-GA-BP…

Abstract

Purpose

For comfort evaluation of underwear pressure, this paper proposes an improved GA algorithm to optimize the weight and threshold of BP neural network, namely PSO-GA-BP neural network prediction model.

Design/methodology/approach

The objective parameters of underwear, body shape data, skin deformation and other data are selected for simulation experiments to predict the objective pressure and subjective evaluation in dynamic and static state. Compared with the prediction results of BP neural network prediction model, GA-BP neural network prediction model and PSO-BP neural network prediction model, the performance of each prediction model is verified.

Findings

The results show that the BP neural network model optimized by PSO-GA algorithm can accelerate the convergence speed of the neural network and improve the prediction accuracy of underwear pressure.

Originality/value

PSO-GA-BP model provides data support for underwear design, production and processing and has guiding significance for consumers to choose underwear.

Details

International Journal of Clothing Science and Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0955-6222

Keywords

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Article

Sifeng Liu, Keqin Sheng and Jeffrey Forrest

The purpose of this paper is to show which models, uncertain or certain, simple or complicated, are more suitable when they are faced with incomplete information and…

Abstract

Purpose

The purpose of this paper is to show which models, uncertain or certain, simple or complicated, are more suitable when they are faced with incomplete information and inaccurate data.

Design/methodology/approach

The characteristics of fuzzy mathematics, grey system theory, rough set theory and the basic characteristics of incomplete information and inaccurate data in uncertain systems are analysed.

Findings

The similarities and differences among fuzzy mathematics, grey system theory, rough set theory and probability statistics are compared. The principle of simplicity of scientific theories, methods, and models are discussed.

Practical implications

It is suggested that the tendency to concentrate on a complicated model isn't always necessary when faced with the condition of incomplete information and inaccurate data.

Originality/value

The paper shows that a more satisfied result can be obtained with an uncertain model than with a meticulous model on a certain situation.

Details

Kybernetes, vol. 41 no. 5/6
Type: Research Article
ISSN: 0368-492X

Keywords

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Article

Rosa Enn

The purpose of this paper is to draw attention to an indigenous community that lives in the periphery of Taiwan. The Dao on Orchid Island have had to face serious abuse of…

Abstract

Purpose

The purpose of this paper is to draw attention to an indigenous community that lives in the periphery of Taiwan. The Dao on Orchid Island have had to face serious abuse of their human rights in terms of ecological exploitation and environmental injustice. The article highlights the empowerment of the indigenous group through collective learning. In this process the importance of being represented at both local and international levels is emphasized. Despite the democratization and implemented mechanism to protect indigenous peoples' rights and dignity, the issue of self‐determination and dependency on financial compensation still remains unsolved.

Design/methodology/approach

Data are collected and elaborated primarily using recognized research methods that are common in social anthropology (Bernard). Field research was conducted in 2007, 2008, and 2011 in Taiwan. A variety of interviews and formal and informal conversations formed the basis of data collection. According to qualitative content analysis, concepts and procedures developed by Gläser and Laudel, Bernard, as well as Schmidt were applied.

Findings

The outcomes of the research highlight the need to investigate the dynamic between modern technologies and the fight of vulnerable minorities in multicultural and democratic countries. Collective learning, solidarity, and presence at national and international levels are essential to improve empowerment to gain justice and respect of human rights.

Research limitations/implications

The indigenous Dao were excluded from decision making processes regarding the government's appropriation of land on Orchid Island to be used to store nuclear waste. The Dao gained power due to educational technologies within a local and global network. Although Taiwan promotes its cultural diversity nowadays, social and environmental justice is still a goal to reach.

Originality/value

The paper provides valuable insights of an indigenous community in Taiwan and their struggles against environmental injustice and exploitation. Due to the fieldwork, a unique and authentic picture of the indigenous peoples' situation is offered.

Details

Multicultural Education & Technology Journal, vol. 6 no. 3
Type: Research Article
ISSN: 1750-497X

Keywords

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Article

Jibing Chen, Yanfang Yin , Jianping Ye and Yiping Wu

The purpose of this paper is to investigate the thermal fatigue behavior of a single Sn-3.0Ag-0.5Cu (SAC) lead-free and 63Sn-37Pb (SnPb) solder joint treated by rapidly…

Abstract

Purpose

The purpose of this paper is to investigate the thermal fatigue behavior of a single Sn-3.0Ag-0.5Cu (SAC) lead-free and 63Sn-37Pb (SnPb) solder joint treated by rapidly alternating heating and cooling cycles.

Design/methodology/approach

With the application of electromagnetic-induced heating, the specimen was heated and cooled, controlled with a system that uses a fuzzy logic algorithm. The microstructure and morphology of the interface between the solder ball and Cu substrate was observed using scanning electron microscopy. The intermetallic compounds and the solder bump surface were analyzed by energy-dispersive X-ray spectroscopy and X-ray diffraction, respectively.

Findings

The experimental results showed that rapid thermal cycling had an evident influence on the surface and interfacial microstructure of a single solder joint. The experiment revealed that microcracks originate and propagate on the superficial oxide of the solder bump after rapid thermal cycling.

Originality/value

Analysis, based on finite element modeling and metal thermal fatigue mechanism, determined that the rimous cracks can be explained by the heat deformation theory and the function of temperature distribution in materials physics.

Details

Soldering & Surface Mount Technology, vol. 27 no. 2
Type: Research Article
ISSN: 0954-0911

Keywords

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