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Article
Publication date: 23 January 2009

Lihui Geng, Tao Zhang, Deyun Xiao and Jingyan Song

The purpose of this paper is to propose an identification algorithm to obtain generalized attitude model (GAM) of satellites in on‐orbit environment, which includes missing…

465

Abstract

Purpose

The purpose of this paper is to propose an identification algorithm to obtain generalized attitude model (GAM) of satellites in on‐orbit environment, which includes missing attitude data and multi‐noise. The identified GAM and noise model are the basis of attitude control and state estimation on‐orbit.

Design/methodology/approach

To cope with noises contaminating both input and output of attitude model, the errors‐in‐variables model is transformed into a traditional Box‐Jenkins model according to the attitude control loop. The wavelet denoising (WD) technique is helpful to predict the missing output data using the identified GAM.

Findings

By the numerical simulation, it is verified that the proposal accompanied with WD has a faster prediction capability than that of the algorithm without WD. As a result, the proposed approach is suitable to attitude model identification of on‐orbit satellites.

Originality/value

This identification algorithm can deal with two kinds of on‐orbit conditions and has a fast parameter convergent rate. Therefore, it has a practical application value in on‐orbit environment.

Details

Aircraft Engineering and Aerospace Technology, vol. 81 no. 2
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 6 January 2012

Qiang Meng, Tao Zhang, Jingfeng He, Jingyan Song and Xuedong Chen

The precise control and dynamic analysis of the electrical Stewart platform have not been so well treated in the literature. This paper aims to design a novel model‐based…

550

Abstract

Purpose

The precise control and dynamic analysis of the electrical Stewart platform have not been so well treated in the literature. This paper aims to design a novel model‐based controller to improve the tracing performance of the electrical Stewart platform. Moreover, the simulations under uncertain environments are used to verify the robustness of the controller.

Design/methodology/approach

In the electrical Stewart platform, there exist two special movements of the motor systems: motor systems' movement with the actuators and meanwhile the rotors and snails' rotation around their axis. The Kane equation is used to compute the driven torque of the movements of motor systems, actuators and movable platform. The improved dynamic models of the electrical Stewart platform which consider the motor systems and actuators' influences are used to design the novel controller. The PID controller and the simple model‐based controller are also developed to compare with the novel one. Moreover, the robustness of the controller is verified by the platform friction and the parameters uncertainty.

Findings

Simulation results show that the novel model‐based controller can gain a better tracing performance than the PID controller and even the simple model‐based controller. Under the environments of the platform with friction and 5% parameters variety, the tracing performance of the novel controller is also satisfactory, which verifies the robustness of the controller. Most importantly, the novel model‐based controller can be used in a higher precision control demand and a more complicated environment.

Originality/value

The main contribution of this paper is to derive a novel model‐based controller considering the motor systems' influence, which enhances the robustness of the controller. To the authors' best knowledge, such a framework for the improved model based controller has not been well treated in the past literature. The conventional PID controller and a simple model‐based controller are also built to verify the advantages of the improved model‐based controller.

Details

Industrial Robot: An International Journal, vol. 39 no. 1
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 6 January 2012

Yi Zhu, Tao Zhang, Jingyan Song and Xiaqin Li

The purpose of this paper is to improve the traditional bug algorithms for the navigation of mobile robots in unknown environments by considering the limitations in previous works…

401

Abstract

Purpose

The purpose of this paper is to improve the traditional bug algorithms for the navigation of mobile robots in unknown environments by considering the limitations in previous works such as generating long path, limited to static environments as well as ignoring implementation issues. With this purpose, a new bug‐type algorithm termed Distance Histogram Bug (DH‐Bug) is proposed for overcoming these limitations.

Design/methodology/approach

DH‐Bug redefines the traditional motion modes and switching criteria to shorten the path length. In order to extend the framework of the traditional bug algorithms to tackle the navigation problem in dynamic environments, a new mode and the related switching conditions are designed for dealing with moving obstacles. Moreover, a realization method termed the Distance Histogram (DH) method which takes many implementation issues into full account is proposed for implementing DH‐Bug on real robots.

Findings

DH‐Bug is convergent in static environments and it also guarantees “approximate” convergence based on several reasonable assumptions when there are moving obstacles. Simulations results show that DH‐Bug generates shorter average path length than some classical Bug algorithms in static environments and it also performs well in most simulations that contain moving obstacles except for some extremely adverse scenarios which have been discussed in the paper. Experiments on real robots further verify its applicability in both static environments and dynamic environments containing moving obstacles.

Originality/value

Compared with previous works, DH‐Bug has three main contributions. First, in static environments, it can shorten the average path length than many classical bug algorithms in the premise of guaranteeing convergence. Second, it can be applied in dynamic environments containing moving obstacles. Third, unlike the previous bug algorithms that always ignore the practical implementation issues, DH‐Bug presents not only an abstract concept, but also a realization approach for realizing this concept on real robots.

Details

Industrial Robot: An International Journal, vol. 39 no. 1
Type: Research Article
ISSN: 0143-991X

Keywords

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Article
Publication date: 22 June 2010

Tao Zhang, Yi Zhu and Jingyan Song

The purpose of this paper is to focus on the local minima issue encountered in motion planning by the artificial potential field (APF) method, investigate the currently existing…

1016

Abstract

Purpose

The purpose of this paper is to focus on the local minima issue encountered in motion planning by the artificial potential field (APF) method, investigate the currently existing approaches and analyze four types of previous methods. Based on the conclusions of analysis, this paper presents an improved wall‐following approach for real‐time application in mobile robots.

Design/methodology/approach

In the proposed method, new switching conditions among various behaviors are reasonably designed in order to guarantee the reliability and the generality of the method. In addition, path memory is incorporated in this method to enhance the robot's cognition capability to the environment. Therefore, the new method greatly weakens the blindness of decision making of robot and it is very helpful to select appropriate behaviors facing to the changeable situation. Comparing with the previous methods which are normally considering specific obstacles, the effectiveness of this proposed method for the environment with convex polygon‐shaped obstacles has been theoretically proved. The simulation and experimental results further demonstrate that the proposed method is adaptable for the environment with convex polygon‐shaped obstacles or non‐convex polygon‐shaped obstacles. It has more widely generality and adaptiveness than other existed methods in complicated unknown environment.

Findings

The proposed method can effectively realize real time motion planning with high reliability and generality. The cognition capability of mobile robot to the environment can be improved in order to adapt to the changeable situation. The proposed method can be suitable to more complex unknown environment. It is more applicable for actual environment comparing with other traditional APF methods.

Originality/value

This paper has widely investigated the currently existed approaches and analyzes deeply on four types of traditional APF methods adopted for real time motion planning in unknown environment with simulation works. Based on the conclusions of analysis, this paper presents an improved wall‐following approach. The proposed method can realize real time motion planning considering more complex environment with high reliability and generality. The simulation and experimental results further demonstrate that the proposed method is adaptable for the environment with convex polygon‐shaped obstacles or non‐convex polygon‐shaped obstacles. It has more widely generality and adaptiveness than other existed methods in complicated unknown environment.

Details

Industrial Robot: An International Journal, vol. 37 no. 4
Type: Research Article
ISSN: 0143-991X

Keywords

Available. Open Access. Open Access
Article
Publication date: 22 November 2024

Feng Zhao, Jianbao Zhang and Zhen Luo

The correlations and deviations between market prices, production prices and values are critical indexes for testing the labor theory of value. However, there is not yet a…

102

Abstract

Purpose

The correlations and deviations between market prices, production prices and values are critical indexes for testing the labor theory of value. However, there is not yet a universally accepted method of solving for the production price vector, and given the complexity and volatility of economic dynamics, production prices based on the assumption of economic equilibrium cannot be accurate measuring. This paper attempts to propose a new approach to test the labor theory of value.

Design/methodology/approach

This paper proposes a different approach. From the perspective of disequilibrium price, the paper deduces that the range of the relative prices of commodities is determined by the relative value, the rate of surplus-value and the technical structure of production inputs, with relative price fluctuating within the value range specified by the labor theory of value under market competition influences.

Findings

With empirical research results based on China’s economic data, this paper not only affirms the scientific and practical explanatory power of the labor theory of value in a more general sense but also uncovers how surplus value is distributed across sectors, which can be used to analyze market competition and technical relations and their impacts on industrial structure and distribution.

Originality/value

The disequilibrium analytical framework provides a new perspective for the empirical study of labor theory of value. Moreover, it evolves the labor theory of value into a robust empirical framework, breaking through the theoretical path of the traditional labor theory of value that is mostly limited to the normative discussion of exploitation.

Details

China Political Economy, vol. 7 no. 1
Type: Research Article
ISSN: 2516-1652

Keywords

Available. Open Access. Open Access
Article
Publication date: 5 December 2024

Xin Fan and Xiaoyu Song

Regulating and guiding the sound development of capital under a socialist system is not only a significant theoretical innovation rooted in Chinese…

51

Abstract

Purpose

Regulating and guiding the sound development of capital under a socialist system is not only a significant theoretical innovation rooted in Chinese practice by the Communist Party of China (CPC) but also a major practical exploration for the smooth progression of the party and the nation’s modernization endeavors.

Design/methodology/approach

Adopting an analytical framework that unifies theoretical, historical and practical logic, this paper explores the rationality of capital’s existence under a socialist system based on the notion that capital is a materialized production relationship. It also examines the staged evolution of capital theory under socialism, highlighting the great leap forward realized by the capital theory of socialism with Chinese characteristics.

Findings

With the CPC Central Committee’s deepening understanding of the capital patterns in the socialist system, capital-related policies have undergone a developmental journey through several stages – from the negation and elimination of capital to the support and operation of capital and finally to the stage of regulating and guiding capital. This reflects the reciprocal and complementary relationship between capital theory and capital policy.

Originality/value

In response to issues such as the disorderly expansion of capital in the new development stage, it is imperative to actively promote a practical pathway safeguarded by the adherence to Party leadership, guided by the capital theory of socialism with Chinese characteristics and targeted toward common prosperity.

Details

China Political Economy, vol. 7 no. 2
Type: Research Article
ISSN: 2516-1652

Keywords

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Article
Publication date: 9 November 2020

Keisuke Kokubun and Misako Yasui

The purpose of this paper is to investigate gender differences in organizational commitment (OC) and the relationship between OC and rewards among employees who work for Japanese…

782

Abstract

Purpose

The purpose of this paper is to investigate gender differences in organizational commitment (OC) and the relationship between OC and rewards among employees who work for Japanese manufacturing companies within China.

Design/methodology/approach

This study utilized hierarchical regression analysis to examine survey data obtained from 27,854 employees who worked for 64 Japanese manufacturing companies within China.

Findings

The results reveal that autonomy and role clarity had a stronger influence, and co-worker support had a weaker influence, on OC for male employees than for female employees. These differences may be because more male employees than female employees prefer working with higher autonomy and well-defined roles than with co-worker support. After all, male employees, who place a great emphasis on independence, competition, decision-making and challenges, rely on intrinsic rewards more than social rewards.

Research limitations/implications

This study used data collected from Japanese manufacturing companies to understand the differences between OC and rewards in local male and female Chinese employees. We recommend that future research uses other national affiliates to clarify the characteristics of male and female Chinese workers more objectively and to test the validity of this research.

Practical implications

The results of this study support revising human resource management practices within multinational enterprises to enable female and male host-country workers to contribute to their companies on a long-term basis by taking into account the differences between the cultures of the home and host countries.

Originality/value

Although previous research has elucidated the OC–rewards relationship in particular countries, it has not met the requirements of foreign managers from different corporate cultures who face differences in the OC–rewards relationship between their male and female employees. In this sense, this research is the first attempt to tackle this theme and contribute to the literature.

Details

Cross Cultural & Strategic Management, vol. 28 no. 3
Type: Research Article
ISSN: 2059-5794

Keywords

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Article
Publication date: 7 January 2021

Antony King Fung Wong, Mehmet Ali Koseoglu and Seongseop (Sam) Kim

This study aims to examine the current state of the research activities of scholars in the hospitality and tourism field by analyzing the first 20 years of the new millennium.

935

Abstract

Purpose

This study aims to examine the current state of the research activities of scholars in the hospitality and tourism field by analyzing the first 20 years of the new millennium.

Design/methodology/approach

Longitudinal analyses using 14,229 journal articles as data source were realized by adopting BibExcel, Gephi and VOSviewer network analysis software packages.

Findings

This study provides a comprehensive overview of the hospitality and tourism research based on authorship and social network analysis, with patterns of prolific authors compared over four distinct periods.

Research limitations/implications

The hospitality and tourism academic society is clearly illustrated by tracing academic publication activities across 20 years in the new millennium. In addition, this study provides a guide for scholars to search for multidisciplinary collaboration opportunities. Government agencies and non-governmental organisations can also benefit from this study by identifying appropriate review panel members when making decisions about hospitality- and tourism-related proposals.

Originality/value

To the best of authors’ knowledge, this study is the first to use bibliometric analysis in assessing research published in leading hospitality and tourism journals across the four breakout periods in the new millennium.

Details

International Journal of Contemporary Hospitality Management, vol. 33 no. 2
Type: Research Article
ISSN: 0959-6119

Keywords

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Article
Publication date: 31 December 2015

ENZE LIU

The purpose of this paper is to provide a historical review of China’s anti-corruption efforts, from the ancient period of Chinese slavery societies to the late 1970s before China…

1133

Abstract

Purpose

The purpose of this paper is to provide a historical review of China’s anti-corruption efforts, from the ancient period of Chinese slavery societies to the late 1970s before China launched its profound economic reform, under the current status of the harsh crusade against corruption that the Chinese new leadership initiated.

Design/methodology/approach

This paper is mainly based on a great deal of historical literature and empirical findings, with relevant comparative analysis on policies and regulations between various periods of China.

Findings

The phenomenon of corruption has existed in Chinese history for thousands of years, throughout Chinese slavery societies, feudal societies, republic period and the People’s Republic of China (PRC). Anti-corruption laws formed an important part of ancient Chinese legal system, and each dynasty has made continuous and commendable progress on fighting such misconduct. Innumerable initiatives have also been taken by the ruling party Chinese Communist Party (CCP) since the founding of the PRC. The PRC government created various specially designed government organizations and a series of updated regulations for preventing economic crimes. They have realized that periodic movements against corruption would no longer be helpful, and the paramount issue nowadays is indeed how bold the leaders are in striking out those unhealthy tendencies.

Originality/value

This paper fills in the blanks in the Western world with a comprehensive description of, and comments on, the historical efforts on China’s corruption and economic crime prevention. It also, in various ways, provides meaningful information that links to China’s current furious war against corruption.

Details

Journal of Financial Crime, vol. 23 no. 1
Type: Research Article
ISSN: 1359-0790

Keywords

Available. Open Access. Open Access
Article
Publication date: 5 December 2024

Zhixuan Feng and Fengyi Liu

Utilizing the Marxist theory of unequal exchange to explain the terms of trade between nations, this paper elucidates one possible mechanism that…

55

Abstract

Purpose

Utilizing the Marxist theory of unequal exchange to explain the terms of trade between nations, this paper elucidates one possible mechanism that gives rise to ecologically unequal exchange between developed and developing economies.

Design/methodology/approach

We propose a two-sector linear production model and demonstrate that a decrease in the organic composition of capital and an increase in the rate of surplus value in a sector will lead to a relative price decrease and value transfer out of that particular sector, as well as increasing the environmental costs of trade. Furthermore, we measure the levels of unequal exchange (value transfer) and ecologically unequal exchange of 40 economies and empirically validate their relationship.

Findings

The findings suggest that an important cause of the ecologically unequal exchange is the value transfer between economies caused by the international division of labor and real wage disparities. The inequality in international trade is a significant factor contributing to the gap in the ecological environment level between developed and developing economies.

Originality/value

By introducing the theory of unequal exchange or value transfer into the analysis of ecological unequal exchange, we provide a mathematical framework for analyzing ecological unequal exchange and a method for calculating the scale of ecological unequal exchange and value transfer, thereby enhancing the theoretical depth and practical significance of the ecological unequal exchange theory.

Details

China Political Economy, vol. 7 no. 2
Type: Research Article
ISSN: 2516-1652

Keywords

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