Xiwen Cai, Haobo Qiu, Liang Gao, Xiaoke Li and Xinyu Shao
This paper aims to propose hybrid global optimization based on multiple metamodels for improving the efficiency of global optimization.
Abstract
Purpose
This paper aims to propose hybrid global optimization based on multiple metamodels for improving the efficiency of global optimization.
Design/methodology/approach
The method has fully utilized the information provided by different metamodels in the optimization process. It not only imparts the expected improvement criterion of kriging into other metamodels but also intelligently selects appropriate metamodeling techniques to guide the search direction, thus making the search process very efficient. Besides, the corresponding local search strategies are also put forward to further improve the optimizing efficiency.
Findings
To validate the method, it is tested by several numerical benchmark problems and applied in two engineering design optimization problems. Moreover, an overall comparison between the proposed method and several other typical global optimization methods has been made. Results show that the global optimization efficiency of the proposed method is higher than that of the other methods for most situations.
Originality/value
The proposed method sufficiently utilizes multiple metamodels in the optimizing process. Thus, good optimizing results are obtained, showing great applicability in engineering design optimization problems which involve costly simulations.
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Zhiyuan Huang, Haobo Qiu, Ming Zhao, Xiwen Cai and Liang Gao
Popular regression methodologies are inapplicable to obtain accurate metamodels for high dimensional practical problems since the computational time increases exponentially as the…
Abstract
Purpose
Popular regression methodologies are inapplicable to obtain accurate metamodels for high dimensional practical problems since the computational time increases exponentially as the number of dimensions rises. The purpose of this paper is to use support vector regression with high dimensional model representation (SVR-HDMR) model to obtain accurate metamodels for high dimensional problems with a few sampling points.
Design/methodology/approach
High-dimensional model representation (HDMR) is a general set of quantitative model assessment and analysis tools for improving the efficiency of deducing high dimensional input-output system behavior. Support vector regression (SVR) method can approximate the underlying functions with a small subset of sample points. Dividing Rectangles (DIRECT) algorithm is a deterministic sampling method.
Findings
This paper proposes a new form of HDMR by integrating the SVR, termed as SVR-HDMR. And an intelligent sampling strategy, namely, DIRECT method, is adopted to improve the efficiency of SVR-HDMR.
Originality/value
Compared to other metamodeling techniques, the accuracy and efficiency of SVR-HDMR were significantly improved. The SVR-HDMR helped engineers understand the essence of underlying problems visually.
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Bottlenecked by rural underdevelopment, China’s overall development is bound to be inadequate and unbalanced. Through a brief retrospect of the reform directed against the…
Abstract
Purpose
Bottlenecked by rural underdevelopment, China’s overall development is bound to be inadequate and unbalanced. Through a brief retrospect of the reform directed against the “equalitarianism (egalitarianism)” in China’s rural areas, as well as the Chinese Government’s conceptual transformation and systemic construction and improvement thereof, the purpose of this paper is to clarify the panoramic significance of rural reform; the necessity, priority, and long-term nature of the current rural development; and the important role of public policy in doing so. It also looks ahead to consider the prospects for future rural reform.
Design/methodology/approach
This paper first reviews the rural reforms that were carried out in 1978. Second, it introduces the government’s conceptual change regarding rural reform and the establishment and improvement of the system that underlies it. Finally, the future of rural reform is envisaged.
Findings
The initial rural reforms brought extensive and profound changes to China’s rural areas. The experience of rural reform has been referred to and escalated by other fields of study. Hence, rural reforms have become something of global significance. Moreover, since the government can undertake reforms well beyond the reach of farmers, its views must be modified in a timely manner, and only then may it reasonably construct and improve the system pertaining to the “three rural issues (agriculture, rural areas, and farmers).”
Originality/value
This paper reviews the rural reforms carried out in 1978. It introduces the government’s change of concept with respect to rural reforms and the establishment and improvement of the system based on the “three rural issues,” thus looking forward to the future of rural reforms. The findings of this paper are of significance to the formulation of future agricultural policies.
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Jingjun Chen, Xiwen Tang, Yuan Xia, Shangfei Bao and Jianting Shen
This study aims to explore the influence of information presentation conditions on the flow experience of digital reading for high school students.
Abstract
Purpose
This study aims to explore the influence of information presentation conditions on the flow experience of digital reading for high school students.
Design/methodology/approach
Firstly, a survey determines the preferred reading medium and the types of texts that high school students frequently read. Secondly, Experiment 1 focuses on the effects of the text type and reading medium on flow experience and reading comprehension. Finally, Experiment 2 addresses a narrative text presented on a smartphone, and discusses the influence of advance organizer, presentation format and page layout on flow experience and reading comprehension.
Findings
In digital reading, the narrative text has a stronger flow experience than explanatory text; the flow experience of reading narration on smartphones is more evident than on computers. The advance organizer and text combined with pictures are more conducive to a flow experience when a smartphone is used as a reading medium. From the perspective of reading comprehension, scrolling is more suitable for reading text combined with pictures and paging best suits pure text.
Originality/value
Through experimental methods, this study reveals the influence of information presentation conditions on the digital reading flow experience, which is a meaningful and innovative topic. The findings can provide more enlightenment and reference for the design and promotion of digital resources and digital reading by teenagers.
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Xiwen Zhang, Zhen Zhang, Wenhao Sun, Jilei Hu, Liangliang Zhang and Weidong Zhu
Under the repeated action of the construction load, opening deformation and disturbed deformation occurred at the precast box culvert joints of the shield tunnel. The objective of…
Abstract
Purpose
Under the repeated action of the construction load, opening deformation and disturbed deformation occurred at the precast box culvert joints of the shield tunnel. The objective of this paper is to investigate the effect of construction vehicle loading on the mechanical deformation characteristics of the internal structure of a large-diameter shield tunnel during the entire construction period.
Design/methodology/approach
The structural response of the prefabricated internal structure under heavy construction vehicle loads at four different construction stages (prefabricated box culvert installation, curved lining cast-in-place, lane slab installation and pavement structure casting) was analyzed through field tests and ABAQUS (finite element analysis software) numerical simulation.
Findings
Heavy construction vehicles can cause significant mechanical impacts on the internal structure, as the construction phase progresses, the integrity of the internal structure with the tunnel section increases. The vertical and horizontal deformation of the internal structure is significantly reduced, and the overall stress level of the internal structure is reduced. The bolts connecting the precast box culvert have the maximum stress at the initial stage of construction, as the construction proceeds the stress distribution among the bolts gradually becomes uniform.
Originality/value
This study can provide a reference for the design model, theoretical analysis and construction technology of the internal structure during the construction of large-diameter tunnel projects.
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Lixue Zou, Xiwen Liu, Wray Buntine and Yanli Liu
Full text of a document is a rich source of information that can be used to provide meaningful topics. The purpose of this paper is to demonstrate how to use citation context (CC…
Abstract
Purpose
Full text of a document is a rich source of information that can be used to provide meaningful topics. The purpose of this paper is to demonstrate how to use citation context (CC) in the full text to identify the cited topics and citing topics efficiently and effectively by employing automatic text analysis algorithms.
Design/methodology/approach
The authors present two novel topic models, Citation-Context-LDA (CC-LDA) and Citation-Context-Reference-LDA (CCRef-LDA). CC is leveraged to extract the citing text from the full text, which makes it possible to discover topics with accuracy. CC-LDA incorporates CC, citing text, and their latent relationship, while CCRef-LDA incorporates CC, citing text, their latent relationship and reference information in CC. Collapsed Gibbs sampling is used to achieve an approximate estimation. The capacity of CC-LDA to simultaneously learn cited topics and citing topics together with their links is investigated. Moreover, a topic influence measure method based on CC-LDA is proposed and applied to create links between the two-level topics. In addition, the capacity of CCRef-LDA to discover topic influential references is also investigated.
Findings
The results indicate CC-LDA and CCRef-LDA achieve improved or comparable performance in terms of both perplexity and symmetric Kullback–Leibler (sKL) divergence. Moreover, CC-LDA is effective in discovering the cited topics and citing topics with topic influence, and CCRef-LDA is able to find the cited topic influential references.
Originality/value
The automatic method provides novel knowledge for cited topics and citing topics discovery. Topic influence learnt by our model can link two-level topics and create a semantic topic network. The method can also use topic specificity as a feature to rank references.
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With the analysis of the causes of corruption, this study aims to investigate specific anti-corruption measures that can be implemented to reform the political system and the…
Abstract
Purpose
With the analysis of the causes of corruption, this study aims to investigate specific anti-corruption measures that can be implemented to reform the political system and the social climate of China.
Design/methodology/approach
This study examines 97 severe corruption cases of high-ranking officials in China, which occurred between 2012 and 2015. As this insinuates that both institutional and social corruption are major problems in China, the analysis delves into multiple facts of corruption, including different types, four primary underlying causes, and suggestions regarding the implementation of three significant governmental shifts that focus on investigation, prevention tactics and legal regulations.
Findings
China’s corruption is not only individual-based but also it has developed into institutional corruption and social corruption. Besides human nature and instinct, the causes of corruption can be organised into four categories, namely, social customs, social transitions, institutional designs and institutional operations. For the removed high-ranking officials, the formation of interest chains was an important underlying cause behind their corruption.
Originality/value
This study makes a significant contribution to the literature because this study provides a well-rounded approach to a complex issue by highlighting the significance of democracy and the rule of law as ways to regulate human behaviour to combat future corruption.
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Qiuhong Chen, Ning Geng and Kan Zhu
The purpose of this paper is to reveal the distributional characteristics and evolutional patterns in source periodicals, topics, authors, funding, and institutes of research…
Abstract
Purpose
The purpose of this paper is to reveal the distributional characteristics and evolutional patterns in source periodicals, topics, authors, funding, and institutes of research papers in Chinese Agricultural Economics so as to understand the current situations and developmental tendency of Chinese agricultural economics research over the past decade.
Design/methodology/approach
Using the citation analysis method, this paper analyzed the distributional characteristics and evolution of source periodicals, fields, authors and topics of 2,203 highly cited journal papers from the database of China National Knowledge Infrastructure (CNKI) and 189 cited journal papers from database of Social Sciences Citation Index (SSCI) in agricultural economics first-authored by Chinese scholars from 2006 to 2015.
Findings
First, over the past decade, agricultural economics research in China has seen a rapid development. Specially, 103 scholars and 42 institutes have played key roles in the development, and 12 Chinese periodicals and 3 international journals have been the most influential outlets. Second, the coverage of the topics in Chinese agricultural economics research is broad and has expanded over the past decade. The rural land issue has been the most popular topic, while the issues regarding rural institutional arrangements and industrialization in rural areas have been explored extensively. However, issues in other fields, such as agricultural markets and trade, rural labor, food safety, etc. have to be further studied. Third, the improvements of economic theory and quantitative analytic techniques, the supports from research funding, and an increase in the collaboration between Chinese scholars and those from other countries have made great contribution to the rapid development of Chinese agricultural economics research over the past decade.
Originality/value
This paper is an original work that identifies the most influential journal papers including highly cited journal papers from CNKI and cited journal papers from SSCI, using citation frequency and standard Essential Science Indicators method. This is a contribution relative to the methods used by previous studies, which did not account for frequency of citation of a paper. Moreover, this study is based on data from two databases, CNKI and SSCI, suggesting that the coverage of sample papers is broader compared to those of previous studies.
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Huang Chunyan, Zhong Funing and He Jun
The purpose of this paper is to analyze and compare the costs of price and income subsidies when the food security policy targets the urban poor. The result may help policymakers…
Abstract
Purpose
The purpose of this paper is to analyze and compare the costs of price and income subsidies when the food security policy targets the urban poor. The result may help policymakers choose a desired subsidy scheme to ensure food security for the urban poor facing food price surge.
Design/methodology/approach
The analysis consists of three parts: constructing an empirical model on provincial panel data in 1993‐2009 estimating the impact of grain price on food security among urban residents by different income level; evaluating the potential costs of shifting to income subsidy aiming to maintain the real income levels of the low income, lowest income or the poor residents if grain price increases by 20 percent; and comparing with the cost of price subsidy to achieve the same policy goal.
Findings
The paper finds that, food price surge will hurt the urban poor much more seriously than the high income population; the rich residents may receive more benefit from price subsidy; and income subsidy has obviously a cost advantage while the targeted people benefit more.
Originality/value
The obvious value of the paper is to show that income subsidy is much more desired than price subsidy, if the policy goal is to help the poor during food price surge.