Hou Liqiang, Cai Yuanli, Zhang Rongzhi, Li Hengnian and Li Jisheng
A multi-disciplinary robust design optimization method for micro Mars entry probe (no more than 0.8 m in diameter) is proposed. The purpose of this paper is to design a Mars entry…
Abstract
Purpose
A multi-disciplinary robust design optimization method for micro Mars entry probe (no more than 0.8 m in diameter) is proposed. The purpose of this paper is to design a Mars entry probe, not only the geometric configuration, but the trajectory and thermal protection system (TPS). In the design optimization, the uncertainties of atmospheric and aerodynamic parameters are taken into account. The probability distribution information of the uncertainties are supposed to be unknown in the design. To ensure accuracy levels, time-consuming numerical models are coupled in the optimization. Multi-fidelity approach is designed for model management to balance the computational cost and accuracy.
Design/methodology/approach
Uncertainties which cannot defined by usual Gaussian probability distribution are modeled with degree of belief, and optimized through with multiple-objective optimization method. The optimization objectives are set to be the thermal performance of the probe TPS and the corresponding belief values. Robust Pareto front is obtained by an improved multi-objective density estimator algorithm. Multi-fidelity management is performed with an Artificial Neural Network (ANN) surrogate model. Analytical model is used first, and then with the improvement of accuracy, rather complex numerical models are activated. ANN updates the database during the optimization, and makes the solutions finally converge to a high-level accuracy.
Findings
The optimization method provides a way for conducting complex design optimization involving multi-discipline and multi-fidelity models. Uncertainty effects are analyzed and optimized through multi-disciplinary robust design. Because of the micro size, and uncertain impacts of aerodynamic and atmospheric parameters, simulation results show the performance trade-off by the uncertainties. Therefore an effective robust design is necessary for micro entry probe, particularly when details of model parameter are not available.
Originality/value
The optimization is performed through a new developed multi-objective density estimator algorithm. Affinity propagation algorithm partitions adaptively the samples by passing and analyzing messages between data points. Local principle component techniques are employed to resample and reproduce new individuals in each cluster. A strategy similar to NSGA-II selects data with better performance, and converges to the Pareto front. Models with different fidelity levels are incorporated in the multi-disciplinary design via ANN surrogate model. Database of aerodynamic coefficients is updated in an online manner. The computational time is greatly reduced while keeping nearly the same accuracy level of high fidelity model.
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Linsheng Huang, Yashan Chen and Yile Chen
This study aims to explore the relationship between folk religious place-making and the development of urban public spaces and summarize its influence on community network…
Abstract
Purpose
This study aims to explore the relationship between folk religious place-making and the development of urban public spaces and summarize its influence on community network construction and daily behavior to discover the authentic practices and role of folk faith culture in social space.
Design/methodology/approach
Taking Macau's Shi Gandang Temple and its belief culture as an example, on-site research, historical evidence and interviews were used to elaborate and analyze the processes of place-making, social functions, management mechanisms and folk culture to establish a new perception of folk religious place-making in contemporary urban spaces.
Findings
The article argues that the culture of folk beliefs profoundly influences urban spaces and the social management system of Macau and has a positive significance in building the local community and geopolitical relations. In addition, it suggests that the participation of folk religious places in local practices is important as key nodes and emotional hubs of local networks, reconciling conflicts between communities of different backgrounds and driving urban spaces toward diversity while forming a positive interaction and friendly cooperation between regional development and self-contained management mechanisms, governance models and cultural orientations.
Originality/value
This study takes an architectural and anthropological perspective of the impact of faith on urban spaces and local governance, using the Shi Gandang Temple in Macau as an example, to complement related studies.
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Guocheng Xiang, Jingjing Liu and Yuxuan Yang
The modernization of China’s economy is an integral part of Chinese-style modernization. According to the principle of unifying…
Abstract
Purpose
The modernization of China’s economy is an integral part of Chinese-style modernization. According to the principle of unifying theoretical, historical and practical logic, theoretically explaining the modernization of China’s economy is both a political necessity and a higher scientific requirement.
Design/methodology/approach
Following this evolutionary line – from modes of production to the general economic development mechanism and then to patterns of economic operation and development – this paper employs the principal contradiction analysis method to offer an interpretation of China’s economic modernization from the broad Marxist political economy perspective.
Findings
In economic terms, “get organized” primarily refers to the development and mutual promotion of team-based and market-based division of labor organizations, as discussed by Karl Marx. “Get organized” (specifically the development of team-based division of labor organizations) acts as the engine of China’s economic modernization and serves as the historical logical starting point. Division of labor is the theoretical logical starting point for interpreting China’s economic modernization. The two of them are congruent, achieving the unity of theoretical and historical logic at the starting point. The development and mutual promotion of these “two types of division of labor” inherently generate the general mechanism of economic development first comprehensively discussed by Marx and Friedrich Engels, which involves the division of labor development and market expansion accumulating cyclically and reinforcing each other. This mechanism drives both the high-speed and high-quality development of China’s economic modernization.
Originality/value
The broad Marxist political economy paradigm facilitates explaining China’s economic modernization theoretically, historically and practically with unified logic. “Get organized” serves as both the engine and the realization mechanism of this modernization, with the Communist Party of China (CPC) consistently being the core force of this organizational effort.
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Abstract
Purpose
The purpose of this paper is to investigate the effects of carbon nanotubes (CNTs) on the mechanical, thermal and colour properties of solvent-containing two-component polyurethane (PU) coating.
Design/methodology/approach
Fourier transform infrared spectroscopy and observation of dispersion stability were used to assess the effects of acid treatment on CNTs. The CNTs and PU composite coating was synthesised by in situ polymerisation and bending polymerisation, and the mechanical, thermal and colour appearance properties of coating were characterised.
Findings
It was found that desirable modifications to CNTs occurred after acid treatment; thus, mainly carboxylic acid groups were introduced onto the surface of CNTs. And the acid-treated CNTs could improve the mechanical and thermal properties of PU coating, and the properties of composite coating was improved more successfully by in situ polymerisation than by blending polymerisation.
Practical implications
The investigation established a method to synthesise CNTs and PU composite coating. The mechanical and thermal properties of PU coating could be improved by the inclusion of CNTs.
Originality/value
This study established a method to synthesise CNTs and PU composite coating by in situ polymerisation and blending polymerisation; the effects of CNTs on modifying mechanical, thermal and colour properties of PU coating were investigated and compared in detail.
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Yaqi Diao, Jihui Wang, Renhong Song, Xue Fei, Zhichang Xue and Wenbin Hu
The purpose of this paper is to prepare a multifunctional nanocomposite that is slow-release and resistant to seawater corrosion and biofouling corrosion and to explore the…
Abstract
Purpose
The purpose of this paper is to prepare a multifunctional nanocomposite that is slow-release and resistant to seawater corrosion and biofouling corrosion and to explore the synergistic effect between the two corrosion inhibitors.
Design/methodology/approach
The morphology, structure and release properties of CAP@HNTs, BTA@HNTs and CAP/BTA@HNTs were investigated by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, specific surface area analysis and UV spectrophotometry. The corrosion resistance and antimicrobial properties were investigated by electrochemical measurements and bioinhibition rate tests, and the synergistic effect between the two corrosion inhibitors was explored by X-ray photoelectron spectroscopy.
Findings
The CAP/BTA@HNTs are responsive to acidic environments and have significantly improved antibacterial and corrosion resistance compared with CAP@HNTs and BTA@HNTs. CAP and BTA have a positive synergistic effect on anticorrosion and antifouling.
Originality/value
Two types of inhibitors, anticorrosion and antifouling, were loaded into the same nanocontainer to prepare a slow-releasable and multifunctional nanocomposite with higher resistance to seawater corrosion and biocorrosion and to explore the synergistic effect of CAP and BTA on corrosion resistance.
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The purpose of this paper is to synthesize and characterize a series of alicyclic two-component waterborne polyurethane (2K-WPU) which is composed of non-ionic polyisocyanate…
Abstract
Purpose
The purpose of this paper is to synthesize and characterize a series of alicyclic two-component waterborne polyurethane (2K-WPU) which is composed of non-ionic polyisocyanate aqueous dispersion and hydroxyl aqueous dispersion.
Design/methodology/approach
The appearances of aqueous dispersions and 2K-WPU films were observed by photographs. The micromorphology of alicyclic polyisocyanate aqueous dispersion was examined by scanning electron microscopy (SEM). The molecule structures of WPU were studied by Fourier transform infrared (FTIR). The effect of NCO:OH molar ratio of two components and trimethylolpropane (TMP) content on the thermal stability, mechanical and water resistance properties of 2K-WPU films was studied.
Findings
It was found by SEM that alicyclic polyisocyanate particles in aqueous dispersion showed a kind of spherical particle appearance, in which hydrophobic polyisocyanate was encapsulated by hydrophilic ether linkages segment. FTIR showed that WPU was polymerized through mixture of polyisocyanate component and hydroxyl component and increasing NCO:OH molar ratio of two components from 1.1:1 to 1.5:1 had increased the content of urea, urethane and allophanate of 2K-WPU films. Increasing NCO:OH molar ratio had improved the mechanical and thermal properties of the 2K-WPU film, but the water resistance of the 2K-WPU film increased first and then weakened. Increasing TMP contents from 1 to 0.75 mol for 1:5 system had improved the mechanical, thermal and water resistance properties of the 2K-WPU film.
Practical implications
The investigation established a method to prepare alicyclic 2K-WPU which is composed of non-ionic polyisocyanate aqueous dispersion and hydroxyl aqueous dispersion. The prepared 2K-WPU film could be applied in the field of waterborne surface coating, e.g. textile, wood and synthetic leather surfaces (Hasan et al., 2017; Akindoyo et al., 2016).
Originality/value
The paper established a method to synthesize alicyclic two-component 2K-WPU. The effect of NCO:OH molar ratio and TMP content on the thermal stability, mechanical and water resistance properties of 2K-WPU films were studied.
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Sumeer Gul, Shazia Bashir and Shabir Ahmad Ganaie
The purpose of this paper is to explore the status of institutional repositories (IRs) in the South Asian region. The various characteristic features of IRs are studied.
Abstract
Purpose
The purpose of this paper is to explore the status of institutional repositories (IRs) in the South Asian region. The various characteristic features of IRs are studied.
Design/methodology/approach
Open directory of open access repositories (DOAR) as a data-gathering tool was consulted for extracting the desired data.
Findings
India, Sri Lanka and Bangladesh lead other South Asian nations in terms of IRs count. Majority of the IRs are operational in nature with higher number of operational IRs from India. In terms of record count, India leads the list. “Journal articles” outscore other content type and majority of the IRs have OAI-PMH as their base URL. DSpace stays a prioritized software for content management in IRs. Majority of the IRs have not defined their content management policies. English stays a prioritized language of the content dotting the South Asian IRs and majority of the IRs not providing usage statistics. A good score of IRs has incorporated Web 2.0 tools in them with RSS as the preferred Web 2.0 tool. A good count of the IRs has not customized their interface. Majority of the IRs have interface in two languages.
Research limitations/implications
The main limitation of the study is that the findings of the research are based on the data collected through the repositories indexed by Open DOAR.
Originality/value
The study tries to explore the characteristic features of IRs from the South Asian region.
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Karl Marx's social capital reproduction theory is his significant contribution to economics. The purpose of this paper is to review the contributions of the exploration of Chinese…
Abstract
Purpose
Karl Marx's social capital reproduction theory is his significant contribution to economics. The purpose of this paper is to review the contributions of the exploration of Chinese economists (especially Professor Liu Guoguang) in the concretization of Marx’s social capital reproduction theory combined with socialist construction since 1949.
Design/methodology/approach
During this process, Professor Liu Guoguang, a famous Chinese Marxist economist, has made an outstanding contribution by creating a Marxist social capital reproduction model with Chinese characteristics and a distinctive Marxist economic growth model. Professor Liu's exploration is still of crucial practical significance to building a socialist market economy today.
Findings
The process and achievements in the sinicization exploration of Marx's social capital reproduction theory were reviewed. With the reform and opening up, fundamental changes have occurred in China's economic system – the centralized planned economic system has been transformed into a socialist market economic system.
Originality/value
The planned management of the national economy is replaced by a macro-regulation system characterized by gross control gradually, and the concepts of agriculture, light industry, and heavy industry, and their intercorrelation are no longer applied in theory and policy. However, the sinicization exploration of Marx's social capital reproduction theory in the older generation of Marxist economists represented by Liu is not only of historical significance but also of important practical significance.