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1 – 10 of 49Teng Shao, Hong Jin and Lihua Zhao
According to the survey and measurement on rural housing in the Northeast severe cold regions of China, this paper analyzed the existing situation and problems of current rural…
Abstract
According to the survey and measurement on rural housing in the Northeast severe cold regions of China, this paper analyzed the existing situation and problems of current rural housing in terms of integral development, functional layout, envelop structure, interior thermal environment, heating system and energy utilization etc.. Based on the climatic features of severe cold regions, as well as rural financial and technical conditions, living and production mode, residential construction characteristics and existing resource status etc., the feasible approaches of achieving building energy saving has been proposed, thus acting as a guidance for new rural housing design in severe cold regions.
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Abstract
Purpose
The finite element method (FEM) is used to calculate the two-dimensional anti-plane dynamic response of structure embedded in D’Alembert viscoelastic multilayered soil on the rigid bedrock. This paper aims to research a time-domain absorbing boundary condition (ABC), which should be imposed on the truncation boundary of the finite domain to represent the dynamic interaction between the truncated infinite domain and the finite domain.
Design/methodology/approach
A high-order ABC for scalar wave propagation in the D’Alembert viscoelastic multilayered media is proposed. A new operator separation method and the mode reduction are adopted to construct the time-domain ABC.
Findings
The derivation of the ABC is accurate for the single layer but less accurate for the multilayer. To achieve high accuracy, therefore, the distance from the truncation boundary to the region of interest can be zero for the single layer but need to be about 0.5 times of the total layer height of the infinite domain for the multilayer. Both single-layered and multilayered numerical examples verify that the accuracy of the ABC is almost the same for both cases of only using the modal number excited by dynamic load and using the full modal number of infinite domain. Using the ABC with reduced modes can not only reduce the computation cost but also be more friendly to the stability. Numerical examples demonstrate the superior properties of the proposed ABC with stability, high accuracy and remarkable coupling with the FEM.
Originality/value
A high-order time-domain ABC for scalar wave propagation in the D’Alembert viscoelastic multilayered media is proposed. The proposed ABC is suitable for both linear elastic and D’Alembert viscoelastic media, and it can be coupled seamlessly with the FEM. A new operator separation method combining mode reduction is presented with better stability than the existing methods.
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Huifang Li, Mi Zhao, Lihua Wu, Piguang Wang and Xiuli Du
The purpose of this paper is to propose a stable high-order absorbing boundary condition (ABC) based on new continued fraction for scalar wave propagation in 2D and 3D unbounded…
Abstract
Purpose
The purpose of this paper is to propose a stable high-order absorbing boundary condition (ABC) based on new continued fraction for scalar wave propagation in 2D and 3D unbounded layers.
Design/methodology/approach
The ABC is obtained based on continued fraction (CF) expansion of the frequency-domain dynamic stiffness coefficient (DtN kernel) on the artificial boundary of a truncated infinite domain. The CF which has been used to the thin layer method in [69] will be applied to the DtN method to develop a time-domain high-order ABC for the transient scalar wave propagation in 2D. Furthermore, a new stable composite-CF is proposed in this study for 3D unbounded layers by nesting the above CF for 2D layer and another CF.
Findings
The ABS has been transformed from frequency to time domain by using the auxiliary variable technique. The high-order time-domain ABC can couple seamlessly with the finite element method. The instability of the ABC-FEM coupled system is discussed and cured.
Originality/value
This manuscript establishes a stable high-order time-domain ABC for the scalar wave equation in 2D and 3D unbounded layers, which is based on the new continued fraction. The high-order time-domain ABC can couple seamlessly with the finite element method. The instability of the coupled system is discussed and cured.
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Zhirui Zhao, Lina Hao, Guanghong Tao, Hongjun Liu and Lihua Shen
This study discusses the tracking trajectory issue of the exoskeleton under the bounded disturbance and designs an useful tracking trajectory control method to solve it. By using…
Abstract
Purpose
This study discusses the tracking trajectory issue of the exoskeleton under the bounded disturbance and designs an useful tracking trajectory control method to solve it. By using the proposed control method, the tracking error can be successfully convergence to the assigned boundary. Meanwhile, the chattering effect caused by the actuators is already reduced, and the tracking performance of the pneumatic artificial muscles (PAMs) elbow exoskeleton is improved effectively.
Design/methodology/approach
A prescribed performance sliding mode control method was developed in this study to fulfill the joint position tracking trajectory task on the elbow exoskeleton driven by two PAMs. In terms of the control structure, a dynamic model was built by conforming to the adaptive law to compensate for the time variety and uncertainty exhibited by the system. Subsequently, a super-twisting algorithm-based second-order sliding mode control method was subjected to the exoskeleton under the boundedness of external disturbance. Moreover, the prescribed performance control method exhibits a smooth prescribed function with an error transformation function to ensure the tracking error can be finally convergent to the pre-designed requirement.
Findings
From the theoretical perspective, the stability of the control method was verified through Lyapunov synthesis. On that basis, the tracking performance of the proposed control method was confirmed through the simulation and the manikin model experiment.
Originality/value
As revealed by the results of this study, the proposed control method sufficiently applies to the PAMs elbow exoskeleton for tracking trajectory, which means it has potential application in the actual robot-assisted passive rehabilitation tasks.
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Qingqing Wu, Xianguan Zhao, Lihua Zhou, Yao Wang and Yudi Yang
With the rapid development of internet technology, open online social networks provide a broader platform for information spreading. While dissemination of information provides…
Abstract
Purpose
With the rapid development of internet technology, open online social networks provide a broader platform for information spreading. While dissemination of information provides convenience for life, it also brings many problems such as security risks and public opinion orientation. Various negative, malicious and false information spread across regions, which seriously affect social harmony and national security. Therefore, this paper aims to minimize negative information such as online rumors that has attracted extensive attention. The most existing algorithms for blocking rumors have prevented the spread of rumors to some extent, but these algorithms are designed based on entire social networks, mainly focusing on the microstructure of the network, i.e. the pairwise relationship or similarity between nodes. The blocking effect of these algorithms may be unsatisfactory in some networks because of the sparse data in the microstructure.
Design/methodology/approach
An algorithm for minimizing the influence of dynamic rumor based on community structure is proposed in this paper. The algorithm first divides the network into communities, and integrates the influence of each node within communities and rumor influence probability to measure the influence of each node in the entire network, and then selects key nodes and bridge nodes in communities as blocked nodes. After that, a dynamic blocking strategy is adopted to improve the blocking effect of rumors.
Findings
Community structure is one of the most prominent features of networks. It reveals the organizational structure and functional components of a network from a mesoscopic level. The utilization of community structure can provide effective and rich information to solve the problem of data sparsity in the microstructure, thus effectively improve the blocking effect. Extensive experiments on two real-world data sets have validated that the proposed algorithm has superior performance than the baseline algorithms.
Originality/value
As an important research direction of social network analysis, rumor minimization has a profound effect on the harmony and stability of society and the development of social media. However, because the rumor spread has the characteristics of multiple propagation paths, fast propagation speed, wide propagation area and time-varying, it is a huge challenge to improve the effectiveness of the rumor blocking algorithm.
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Xu Ren, Xiaofang Deng and Lihua Liang
This paper aims to investigate how project nature affects the effectiveness of knowledge transfer between projects in project-based organizations (PBOs) and to analyze the roles…
Abstract
Purpose
This paper aims to investigate how project nature affects the effectiveness of knowledge transfer between projects in project-based organizations (PBOs) and to analyze the roles of inter-project communication, transfer intention and information technology (IT) in the influencing process.
Design/methodology/approach
This paper adopted a questionnaire survey method to collect data from construction enterprises in China and subsequently proceeded to structural equation modeling analysis with a total of 261 samples.
Findings
The results indicate that the similarity of projects could promote the inter-project communication and improve transfer intention, which further influences knowledge transfer effectiveness positively within PBOs. The urgency of projects has a negative impact on inter-project communication and transfer intention. The temporality of projects also negatively affects inter-project communication. They consequently hinder the knowledge transfer behaviors between projects. Additionally, the application of IT improves the frequency of communication and makes up for the negative impact of geographical distance between projects on knowledge transfer.
Practical implications
Based on the results, a series of strategies is recommended to improve knowledge transfer effectiveness between projects, including standardizing project management, promoting information construction, establishing a post-project evaluation system and creating a shared culture, so that the competitive advantages of PBOs could be improved.
Originality/value
The study explores the factors influencing knowledge transfer between projects from the perspective of project nature and provides guidance for enhancing knowledge management and project management practices.
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Lihua Chen, Yi Lu and Rui Zhao
The purpose of this paper is make a significant contribution to the supply chain knowledge system through research on modern supply chain system in China, providing guidance for…
Abstract
Purpose
The purpose of this paper is make a significant contribution to the supply chain knowledge system through research on modern supply chain system in China, providing guidance for theoretical research such as methodology of dynamic resource allocation and application of innovative small- and middle-sized service system in the supply chain.
Design/methodology/approach
The paper uses structural analysis of Chinese competitive advantage, and it applies comparative analysis of supply chain models in China, the USA and Japan through the factor disintegration of trading environment.
Findings
China’s supply chain model has virtual scale and virtual capabilities. The relationship with suppliers is more dynamic. The requirements for resolving uncertainty are higher. Business transfer is more frequent.
Research limitations/implications
Researchers are encouraged to propose the specific supply chain models in China further with the game theory, auction theory, etc.
Practical implications
It provides advice for government policy making and gives Chinese enterprises guidance to improve operation management.
Originality/value
This paper specifically analyzes characteristics of China supply chain and gives enlightenment for supply chain innovation.
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Zheng Liu, Na Huang, Chunjia Han, Mu Yang, Yuanjun Zhao, Wenzhuo Sun, Varsha Arya, Brij B. Gupta and Lihua Shi
The aim of this study was to analyze the effects of carbon reduction efforts and preservation efforts on system benefits in the cold chain industry of fresh products.
Abstract
Purpose
The aim of this study was to analyze the effects of carbon reduction efforts and preservation efforts on system benefits in the cold chain industry of fresh products.
Design/methodology/approach
This study develops an optimal decision game model for the fresh products in the cold chain, incorporating the retailer's preservation effort and the supplier's carbon emission reduction effort. It quantifies the relationship between carbon emission reduction effort, preservation effort and system profit. The model considers parameters like carbon trading price, consumer low-carbon preference and consumer freshness preference, reflecting real-world conditions and market trends. Numerical simulations are conducted by varying these parameters to observe their impact on system profit.
Findings
Under the carbon cap-and-trade policy, the profit of the fresh cold chain system is higher than that of the fresh cold chain system without carbon constraints, and the profit of the supplier under decentralized decision-making is increased by nine times in the simulation results. The increase in carbon trading prices can effectively improve the freshness level of fresh products cold chain, carbon emission reduction level and system profit.
Originality/value
This study comprehensively considers the factors of freshness and carbon emission reduction, provides the optimal low-carbon production decision-making reference for the fresh food cold chain and promotes the sustainable development of the fresh food cold chain.
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Gaoyan Lyu, Lihua Chen and Baofeng Huo
The purpose of this paper is to investigate how different logistics resources and resource patterns, such as logistics infrastructure, logistics location, logistics knowledge and…
Abstract
Purpose
The purpose of this paper is to investigate how different logistics resources and resource patterns, such as logistics infrastructure, logistics location, logistics knowledge and logistics information, affect logistics capabilities and operational performance.
Design/methodology/approach
Based on data collected from 273 companies in China, this study examines impacts of individual logistics resource dimensions on resource integration capability, customer service capability and operational performance through contingency approach. Furthermore, three logistics resource patterns are identified and linked with resource integration capability and operational performance through configuration approach.
Findings
Contingency results show that different logistics resources have different impacts on resource integration capability and operational performance. Configuration results reveal that companies’ capabilities and operational performance vary for different logistics resource patterns: the high-uniform pattern has a better resource integration capability and operational performance than other patterns, while all logistics resource patterns have similar customer service capability levels.
Research limitations/implications
Future studies should examine other resource capabilities and performance indicators of companies and extend this study to other countries and regions.
Originality/value
This study contributes to the logistics resource literature through empirically investigating relationships among logistics resources, resource integration capability and operational performance using contingency approach, and through identifying different logistics resource patterns based on configuration approach. The findings extend the logistics resource literature, particularly on research of logistics parks in China.
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This paper seeks to make people aware of the condition of Chinese cultural information resources sharing through the case of the National Cultural Information Resources Sharing…
Abstract
Purpose
This paper seeks to make people aware of the condition of Chinese cultural information resources sharing through the case of the National Cultural Information Resources Sharing Project (NCIRSP). The paper seeks to provide an overview of NCIRSP, and summarize its achievements.
Design/methodology/approach
This paper first indicates that cultural information resources sharing is a kind of special resources sharing, and NCIRSP in China is a good example of the realization of this kind of resources sharing. The author introduces NCIRSP in general, and analyzes the operation and its achievements. The author considers that there are some problems which exist in the practice of NCIRSP which will hinder its development and proposes measures to solve those problems.
Findings
NCIRSP is a project which is advanced by the Chinese government as well as governments at other levels, which means the project has a strong organization and powerful support. The operation of NCIRSP is made up by four aspects: the network, the construction of digital resources, the implementation of technology, and the websites of services. These four aspects determine the effective operation of NCIRSP and promote the project to make great achievements. Meanwhile, there are problems which hinder NCIRSP from developing further, including the unbalanced collection of cultural information resources in various areas, the scattered storage of resources, and the absence of a sophisticated training mechanism for professionals engaged in the project. Measures to solve the problems are suggested.
Originality/value
NCIRSP is an innovative project supported by the Government of China, even though it is rarely known about by people outside China. This paper introduces NCIRSP in detail, and makes people aware of the situation of cultural information resources sharing in China.
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