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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Yin Pan and Tiejun Zhou
Due to the rapid urbanization in China, the living environment in urban areas improves considerably, while that in rural settlements does not improve remarkably, or even worsens…
Abstract
Due to the rapid urbanization in China, the living environment in urban areas improves considerably, while that in rural settlements does not improve remarkably, or even worsens. The purpose of the research is to propose an organizational approach to the improvement of the living environment in the poverty-stricken rural settlements and an architectural design pattern under a variety of requirements in the context of China’s rapid urbanization and socio-economic development in the redevelopment of rural settlements in Yongsheng Village, Lizhuang Town, Yibin City of Sichuan Province in Southwest China. In this redevelopment project, the architects, as the important third party, are not just architects in the traditional sense in that they are involved in the organizational process and architectural design throughout the whole project. The redevelopment project has been completed, and is aimed at providing a scientific redevelopment model and a design method for other rural residents by guiding them in the improvement of their living environment under a variety of restrictions.
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Wenxiang Sun, Jisheng Peng and Yong Huang
The purpose of this paper is to implement a comparative analysis on the evolution of technology policies of central and local governments in China and to uncover the relationship…
Abstract
Purpose
The purpose of this paper is to implement a comparative analysis on the evolution of technology policies of central and local governments in China and to uncover the relationship of technology policies.
Design/methodology/approach
A quantitative method based on policy contents from policy power, policy goals and policy instruments was developed to build a policy database and, taking Jiangsu province's policy practice as an example, was used to comparatively analyze the evolutionary process and the relationship of technology policies issued by central and local governments in China.
Findings
Comparative analysis shows that technology policies of central government are focused on the strategy of “Market in Exchange for Technology”. However, technology absorption as the critical part to realize the strategy was neglected due to the competition of interests among different agents. Local government has gradually developed a different technology development strategy to promote independent innovation on the basis of its better economic and science and technology conditions. So, the correlation coefficients of technology policies between central and local (Jiangsu) governments on policy power, policy instruments and policy goals have decreased continually.
Research limitations/implications
Because of the limitation of data and time, this paper adopted quantification criteria on the contents of policies. Also, it is necessary to explore the coordination of technology policies between central and local governments.
Practical implications
Chinese technology policies should balance administrative rights reasonably between central and local governments and promote the coordination among the central authority, ministries, commissions, local governments and enterprises.
Originality/value
This paper has made a novel quantitative and comparative analysis about the relationship of technology policies between central and local (Jiangsu) governments.
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Wen Zeng, Changqing Yao and Hui Li
Science and technology policy plays an important role in promoting the development of economic and social development in China. At present, the research on science and technology…
Abstract
Purpose
Science and technology policy plays an important role in promoting the development of economic and social development in China. At present, the research on science and technology policy is mainly focused on the basic theories and some quantitative research. The analyses for contents of massive science and technology policies are relatively less. This paper makes use of semantic technologies to extract and analyze the relatively important information from massive science and technology policies. The purpose of this paper is to facilitate users to quickly and effectively obtain valuable information from the massive science and technology policies. The key methods and study results are presented in the paper. The study results can provide references for further study and application in China.
Design/methodology/approach
The paper presented the analysis model and method for science and technology policy in China. The terms and sentences are the important information in the science and technology policy. The study adopted the technology of natural language processing to analyze the linguistics characteristics of terms and combined with statistical analyses to extract the terms from Chinese science and technology policy. Then, the authors designed an algorithm, calculated and analyzed the important sentences in Chinese science and technology policies. The experiments were run on the Java test platform.
Findings
This paper put forward the analysis model and method for science and technology policy in China. The study obtained the following conclusions: term extraction of science and technology policy: the paper analyzed characteristic of terms in Chinese science and technology policy and designed a method of extracting a term that was suitable for the science and technology policy. The calculation of important sentences for science and technology policy: the paper designed an algorithm and calculated the importance of the sentences to obtain valuable information from the massive science and technology policies.
Research limitations/implications
In our methods, there are some defects to be improved or solved in the future. For example, the precision of algorithm needs to be improved. The significance of this paper is to propose and use the analysis model to process Chinese science and technology policy; we can provide an auxiliary tool to help policy beneficiaries. Enterprises and individuals can be more effective to extraction and mining information from massive science and technology policy and find the target policy.
Practical implications
To verify the effectiveness of the method, the paper selected the real policies about the new energy vehicles as experimental data; at the same time, the paper added uncorrelated policies. It used the proposed analysis model of science and technology policy to calculate and find out the relatively important sentences. The results of study showed that the proposed method can obtain better performance. It verified the validity of this method. The model and method have been applied to actual retrieval system.
Social implications
The proposed model and method in the paper have been applied to actual retrieval system for users.
Originality/value
The paper proposed the new analysis model and method to analyze science and technology policies in China. The presented model and method are a new attempt. According to the experimental results, this exploration and study are valuable. In addition, the idea and method will give a good start for improving information services of massive science and technology policies in China.
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Mohamed El-Amin, Jisheng Kou and Shuyu Sun
This paper aims to introduce modeling, numerical simulation and convergence analysis of the problem of nanoparticles’ transport carried by a two-phase flow in a porous medium. The…
Abstract
Purpose
This paper aims to introduce modeling, numerical simulation and convergence analysis of the problem of nanoparticles’ transport carried by a two-phase flow in a porous medium. The model consists of equations of pressure, saturation, nanoparticles’ concentration, deposited nanoparticles’ concentration on the pore-walls and entrapped nanoparticles concentration in pore-throats.
Design/methodology/approach
A nonlinear iterative IMPES-IMC (IMplicit Pressure Explicit Saturation–IMplicit Concentration) scheme is used to solve the problem under consideration. The governing equations are discretized using the cell-centered finite difference (CCFD) method. The pressure and saturation equations are coupled to calculate the pressure, and then the saturation is updated explicitly. Therefore, the equations of nanoparticles concentration, the deposited nanoparticles concentration on the pore walls and the entrapped nanoparticles concentration in pore throats are computed implicitly. Then, the porosity and the permeability variations are updated.
Findings
Three lemmas and one theorem for the convergence of the iterative method under the natural conditions and some continuity and boundedness assumptions were stated and proved. The theorem is proved by induction states that after a number of iterations, the sequences of the dependent variables such as saturation and concentrations approach solutions on the next time step. Moreover, two numerical examples are introduced with convergence test in terms of Courant–Friedrichs–Lewy (CFL) condition and a relaxation factor. Dependent variables such as pressure, saturation, concentration, deposited concentrations, porosity and permeability are plotted as contours in graphs, whereas the error estimations are presented in a table for different values of the number of time steps, number of iterations and mesh size.
Research limitations/implications
The domain of the computations is relatively small; however, it is straightforward to extend this method to the oil reservoir (large) domain by keeping similar definitions of CFL number and other physical parameters.
Originality/value
The model of the problem under consideration has not been studied before. Also, both solution technique and convergence analysis have not been used before with this model.
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This paper aims to collect and compile the historical data of Guanfu Salt Farm, officially built by the Song Dynasty (960–1279) within modern Hong Kong territories, to reconstruct…
Abstract
Purpose
This paper aims to collect and compile the historical data of Guanfu Salt Farm, officially built by the Song Dynasty (960–1279) within modern Hong Kong territories, to reconstruct its history for the reflection of Hong Kong society of the time.
Design/methodology/approach
This paper is largely based on identification and analysis of historical documents, including keyword search on electronic databases and verification with the original sources, with reference to archaeological findings when necessary.
Findings
This paper reconstructs the history of Guanfu Salt Farm based on documentary sources with reference to archaeological findings. English translation of Chinese sources is also provided when necessary.
Originality/value
There has been an absence of systematic compilation of historical data of Hong Kong during the Song Dynasty, which are limited in quantity and scattered across different sources. This paper seeks to fill the vacuum of knowledge about pre-colonial Hong Kong, with a more comprehensive reconstruction of the history of Guanfu Salt Farm.
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In 2017, the Chinese Super League (CSL), the first professional football division in the People’s Republic of China (PRC), became the highest-spending league in the international…
Abstract
Purpose
In 2017, the Chinese Super League (CSL), the first professional football division in the People’s Republic of China (PRC), became the highest-spending league in the international players’ transfer market, with a total spending of €377m. Moreover, the government of the PRC is backing the CSL with an ambitious football plan. Therefore, the purpose of this paper is to examine the governance of the CSL by questioning the organisational viability of the league.
Design/methodology/approach
In addition to the relevant international literature, this study is based on 14 recent scholarly articles published in Mandarin from 2013 to 2018 to reflect the national academic debate. Moreover, website research on all CSL clubs has been conducted. The institutional analysis follows the integrative change model of Cunningham (2002) complemented by agency and bureaucracy theory.
Findings
The CSL still faces substantial governance problems caused by the divergence of goal setting, organisational inefficiencies and compliance issues. The organisational change is notably constrained by internal competitive value commitments and external power dependency.
Research limitations/implications
The institutional findings on the CSL provide a starting point for empirical studies. The approach contributes to the theory of sport governance processes.
Practical implications
The material and insights are informative for decision makers to evaluate the competitiveness of the CSL.
Originality/value
This paper is the first international in-depth analysis of the governance of the CSL using the body of knowledge published in Mandarin.
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The purpose of this paper is to reveal the characteristics of strategic behavior during knowledge cooperation in organization and compare the differences in strategy choice…
Abstract
Purpose
The purpose of this paper is to reveal the characteristics of strategic behavior during knowledge cooperation in organization and compare the differences in strategy choice between knowledge transferor and knowledge receiver under intricate context consisting of two different objective orientations (organizational and individual) and two different information conditions (perfect and imperfect information) that represent different knowledge application contexts (conventional and available knowledge and intricate and personalized knowledge). Moreover, this paper also wishes to develop a new analysis paradigm of dynamic cooperation game to the micro-interactive mechanism research on individuals’ knowledge sharing in organization.
Design/methodology/approach
Through comparing and referring to previous literatures, and considering the authentic knowledge cooperation practice, this paper first suggested that the behavior characteristics of knowledge sharing between individuals in organization should be observed from the perspective of dynamic cooperation game that would accurately describe the “coopetition” essence of knowledge sharing. Further, an intricate multi-analysis context including two different objective orientations and two different information conditions was constructed. Under this multi-analysis context, the objective functions of knowledge transferor (knowledge output) and knowledge receiver (knowledge returning) were established respectively. Lastly, according to the revenue optimum principle of organizational and individual the strategic choice characteristics were analyzed through the Nash equilibrium to analyze objective functions.
Findings
“Knowledge transaction” motive is classic strategic characteristic of individuals’ knowledge cooperation, and to increase competitiveness of knowledge sharer is a crucial prerequisite for knowledge sharing under any analysis context combination (no matter organizational or individual objective, no matter perfect or imperfect information). Knowledge sharing appears more conservative and stringent under imperfect information condition, and the effort level of knowledge transferring is strategically adjusted according to the value assessment of received knowledge. The institutional constraints and incentives have little effect on the promotion of knowledge sharing under the imperfect information condition where professional knowledge is more intricate, personalized and implicit, because organization members are more sensitive to knowledge competitiveness.
Originality/value
This paper provides a knowledge sharing study with a new analysis paradigm from micro-interactive perspective by aiming at the “coopetition” essence of knowledge cooperation in organization. This analysis paradigm chooses the way of dynamic cooperation game to reveal the strategic characteristics of knowledge sharing among individuals (knowledge transferor and knowledge receiver) and to assess the role of institutional constraints and incentives in promoting the knowledge sharing. At the same time, the establishing of multi-context model with two different perspective dimensions (objective orientation and information condition) make research closer to the authentic circumstance of knowledge cooperation in organization.
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Wenjing Zhu, Dexin Zhang, Jihe Wang and Xiaowei Shao
The purpose of this paper is to present a novel high-precision relative navigation method for tight formation-keeping based on thrust on-line identification.
Abstract
Purpose
The purpose of this paper is to present a novel high-precision relative navigation method for tight formation-keeping based on thrust on-line identification.
Design/methodology/approach
Considering that thrust acceleration cannot be measured directly, an on-line identification method of thrust acceleration is explored via the estimated acceleration of major space perturbation and the inter-satellite relative states obtained from space-borne acceleration sensors; then, an effective identification model is designed to reconstruct thrust acceleration. Based on the identified thrust acceleration, relative orbit dynamics for tight formation-keeping is established. Further, using global positioning system (GPS) measurement information, a modified extended Kalman filter (EKF) is suggested to obtain the inter-satellite relative position and relative velocity.
Findings
Compared with the normal EKF and the adaptive robust EKF, the proposed modified EKF has better estimation accuracy in radial and along-track directions because of accurate compensation of thrust acceleration. Meanwhile, high-precision relative navigation results depend on high-precision acceleration sensors. Finally, simulation studies on a chief-deputy formation flying control system are performed to verify the effectiveness and superiority of the proposed relative navigation algorithm.
Social implications
This paper provides a reference in solving the problem of high-precision relative navigation in tight formation-keeping application.
Originality/value
This paper proposes a novel on-line identification method for thrust acceleration and shows that thrust identification-based modified EKF is more efficient in relative navigation for tight formation-keeping.