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1 – 10 of 43Bo Yan, Xiao-hua Wu, Bing Ye and Yong-wang Zhang
The Internet of Things (IoT) is used in the fresh agricultural product (FAP) supply chain, which can be coordinated through a revenue-sharing contract. The purpose of this paper…
Abstract
Purpose
The Internet of Things (IoT) is used in the fresh agricultural product (FAP) supply chain, which can be coordinated through a revenue-sharing contract. The purpose of this paper is to make the three-level supply chain coordinate in IoT by considering the influence of FAP on market demand and costs of controlling freshness on the road.
Design/methodology/approach
A three-level FAP supply chain that comprises a manufacturer, distributor, and retailer in IoT is regarded as the research object. This study improves the revenue-sharing contract, determines the optimal solution when the supply chain achieves maximum profit in three types of decision-making situations, and develops the profit distribution model based on the improved revenue-sharing contract to coordinate the supply chain.
Findings
The improved revenue-sharing contract can coordinate the FAP supply chain that comprises a manufacturer, distributor, and retailer in IoT, as well as benefit all enterprises in the supply chain.
Practical implications
Resource utilization rate can be improved after coordinating the entire supply chain. Moreover, loss in the circulation process is reduced, and the circulation efficiency of FAPs is improved because of the application of IoT. The validity of the model is verified through a case analysis.
Originality/value
This study is different from other research in terms of the combination of supply chain coordination, FAPs, and radio frequency identification application in IoT.
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Wenqing Wu, Xin Ma, Yuanyuan Zhang, Yong Wang and Xinxing Wu
The purpose of this paper is to study a fractional grey model FAGM(1,1,tα) based on the GM(1,1,tα) model and the fractional accumulated generating operation, and then predict the…
Abstract
Purpose
The purpose of this paper is to study a fractional grey model FAGM(1,1,tα) based on the GM(1,1,tα) model and the fractional accumulated generating operation, and then predict the national health expenditure, the government health expenditure and the out-of-pocket health expenditure of China.
Design/methodology/approach
The presented univariate grey model is systematically studied by using the grey modelling technique, the fractional accumulated generating operation and the trapezoid approximation formula of definite integral. The optimal system parameters r and α are evaluated by the particle swarm optimisation algorithm.
Findings
The expressions of the time response function and the restored values of this model are derived. The GM(1,1), NGM(1,1,k,c) and GM(1,1,tα) models are particular cases of the FAGM(1,1,tα) model with deterministic r and α. Compared with other forecasting models, the results of the FAGM(1,1,tα) model have higher precision.
Practical implications
The superiority of the new model has high potential to be used in the medicine and health fields and others. Results can provide a guideline for government decision making.
Originality/value
The univariate fractional grey model FAGM (1,1,tα) successfully studies the China’s health expenditure.
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Yong Wang and Xiaotian (Tina) Zhang
Initial public offering (IPO) underpricing remains a puzzle after decades of investigation. The stock markets in emerging economies are attractive to international investors but…
Abstract
Initial public offering (IPO) underpricing remains a puzzle after decades of investigation. The stock markets in emerging economies are attractive to international investors but their unique characteristics need to be examined. Chinese stock markets experienced much more significant IPO underpricing than most other stock markets in the world. This paper offers a two-period wealth maximum model to explain the strategic IPO underpricing by state owners. Given the fact that the entire IPO procedure, including IPO price, is regulated and controlled by state owners, we argue that state owners strategically underprice the IPO, because they care less about the IPO proceeds but more about the wealth gain after IPO. The empirical finding of a positive relationship between IPO underpricing and state ownership in Chinese stock market is consistent with the wealth maximization hypothesis of IPO pricing. The paper offers better understanding for IPO procedure of state-owned enterprises in emerging markets.
Chuanbo Zheng, Cheng Zhang, Xiao Yong Wang and Jie Gu
Duplex stainless steel is composed of equal amounts of austenite and ferrite, which has excellent corrosion resistance and strength. However, after the metal was welded, the ratio…
Abstract
Purpose
Duplex stainless steel is composed of equal amounts of austenite and ferrite, which has excellent corrosion resistance and strength. However, after the metal was welded, the ratio of austenite and ferrite in the joint is unbalanced, and secondary phase precipitates are produced, which is also an important cause of pitting corrosion in the joint.
Design/methodology/approach
This paper aims to study the mechanical and corrosion behavior of welded joints, by adjusting the welding parameters of laser hybrid welding, dual heat sources are used to weld 2205 duplex stainless steel. The two-phase content of different parts of the welded joint is measured to study the influence of the ratio of the two-phase on the mechanical and corrosion properties of the joint.
Findings
The ratio of austenite and ferrite in different welded joints has an obvious difference, and from top to bottom, the austenite content decreased gradually, and the ferrite content increased gradually. The harmful phases are precipitated in the middle and lower part of the joint. The strength of welded joints is slightly lower than that of base metal. At the same time, the fracture analysis shows that some ferrite phases are affected by the precipitate in the grain and produce quasi-cleavage fracture. The corrosion results show that the corrosion resistance of the welded joints is lower than that of the base metal, and the concentration of chloride ions affects the corrosion resistance.
Originality/value
In this paper, the authors use the influence of different welding processes on the two-phase ratio of the joint to further study the influence of the microstructure on the corrosion resistance and mechanical properties of the weld.
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Hu Chen, Hong Li, Fei Lin, Yi-Jiao Zhao, Yu-Jiao Guo, Xin-yue Zhang, Yong Wang and Peijun Lyu
This paper aims to use cone-beam computed tomography (CBCT) and computer-aided design/3D printing technology to design and fabricate a drill guide template for access cavity…
Abstract
Purpose
This paper aims to use cone-beam computed tomography (CBCT) and computer-aided design/3D printing technology to design and fabricate a drill guide template for access cavity preparation of permanent molars, and conduct a preliminary evaluation of its effectiveness.
Design/methodology/approach
CBCT scans were performed on two permanent maxillary first molars extracted due to periodontitis. Based on the scans, guide templates of access cavities were designed. The angle of the guiding cylinders was determined based on the direction of the long axis of the tooth. A 3D resin printer with high resolution was used to print the guide templates. The printed guide templates were used by a dentist with specialized clinical experience to perform access cavity preparation in a dental simulator. Then the prepared access cavities were scanned again by CBCT, and scan data were compared to the design data.
Findings
The 3D printed drill guide template had a close fit with the extracted tooth fit. The access cavity prepared using the guide template enabled the removal of the pulp chamber roof, and formed a straight-line access. Points were selected for measurement at regularly spaced intervals of 0.5 mm along the side wall of the access cavity. The mean deviation between the actual access cavities of the two permanent maxillary first molars and the designed cavities was less than 0.1 mm, with a maximum deviation of about 0.5 mm, showing a good conformance between the actual cavity and the designed cavity.
Originality/value
A drill guide template was designed and fabricated by 3D printing technology, which easily guided burs to complete the access cavity preparation work forming an ideal cavity shape with satisfying accuracy, and thus may reduce the complications during pulp chamber entry.
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Adhi Alfian, Hamzah Ritchi and Zaldy Adrianto
Increased fraudulent practices have heightened the need for innovation in anti-fraud programs, necessitating the development of analytics techniques for detecting and preventing…
Abstract
Purpose
Increased fraudulent practices have heightened the need for innovation in anti-fraud programs, necessitating the development of analytics techniques for detecting and preventing fraud. The subject of fraud analytics will continue to expand in the future for public-sector organizations; therefore, this research examined the progress of fraud analytics in public-sector transactions and offers suggestions for its future development.
Design/methodology/approach
This study systematically reviewed research on fraud analytics development in public-sector transactions. The review was conducted from June 2021 to June 2023 by identifying research objectives and questions, performing literature quality assessment and extraction, data synthesis and research reporting. The research mainly identified 43 relevant articles that were used as references.
Findings
This research examined fraud analytics development related to public-sector financial transactions. The results revealed that fraud analytics expansion has not spread equally, as most programs have been implemented by governments and healthcare organizations in developed countries. This research also exposed that the analytics optimization in fraud prevention is higher than for fraud detection. Such analytics help organizations detect fraud, improve business effectiveness and efficiency, and refine administrative systems and work standards.
Research limitations/implications
This research offers comprehensive insights for researchers and public-sector professionals regarding current fraud analytics development in public-sector financial transactions and future trends.
Originality/value
This study presents the first systematic literature review to investigate the development of fraud analytics in public-sector transactions. The findings can aid scholars' and practitioners' future fraud analytics development.
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Pingping Hou, HongYan Huang, Yong Wang, Jun Zhang and Dewen Sun
The purpose of this study is to prepare a robust superhydrophobic coating on concrete substrate with remarkable chemical and mechanical durability through “all-covalent” strategy.
Abstract
Purpose
The purpose of this study is to prepare a robust superhydrophobic coating on concrete substrate with remarkable chemical and mechanical durability through “all-covalent” strategy.
Design/methodology/approach
Amino-modified silica nano/micro-particles were prepared through two synthetic steps. “All-covalent” strategy was introduced to prepare a robust superhydrophobic coating on concrete surface via a “all-in-one” dispersion and a simple spraying method. The successful construction of the products was confirmed by Fourier transform infrared spectroscopy, water contact angles (WCA), X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM). The concrete protective properties were verified by solution immersion test, pull-off test and rapid chloride migration coefficient test. The mechanical durability was tested by falling sand impact.
Findings
Hierarchical structures combined with the low-surface-energy segments lead to typically superhydrophobic coating with a WCA of 156° and a sliding angle of 1.3°. The superhydrophobic coating prepared through “all-covalent” strategy not only improves chemical and mechanical durability but also achieves higher corrosion and wear resistance than the comparison sample prepared by physically blending strategy. More importantly, the robust superhydrophobic coating showed excellent adhesion and protective performance of concrete engineerings.
Practical implications
This new “all-covalent” superhydrophobic coating could be applied as a concrete protective layer with properties of self-cleaning, anti-graffiti, etc.
Originality/value
Introduction of both silica nanoparticles and silica microparticles to prepare a robust superhydrophobic coating on concrete surface through “all-covalent” strategy has not been systematically studied previously.
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Hong-Feng Li, Jun Sun, Xiao-Yong Wang, Lei-Lei Xing and Guang-Zhu Zhang
The purpose of this paper is to add expanded perlite (EP) immobilized microorganisms that replace part of the standard sand in mortar to improve the self-healing ability of mortar…
Abstract
Purpose
The purpose of this paper is to add expanded perlite (EP) immobilized microorganisms that replace part of the standard sand in mortar to improve the self-healing ability of mortar cracks and reduce the water absorption of mortar after healing.
Design/methodology/approach
Bacillus pseudofirmus spores were immobilized with EP particles as self-healing agents. The effects of adding self-healing agents on the compressive strength of mortar specimens were observed. The ability of mortar specimens to heal cracks was evaluated using crack microscopic observation and water absorption experiments. The filler at the cracks was microscopically analyzed by scanning electron microscope and X-ray diffraction experiments.
Findings
First, the internal curing effect of EP promotes the hydration of cement in mortar, which generates more amount and denser crystal structure of Ca(OH)2 at mortar cracks and improves the self-healing ability of mortar. Second, the self-healing ability of mortar improves with the increase of self-healing agent admixture. Adding a self-healing agent of high admixture makes the planar undulation of calcite crystal accumulation at mortar cracks more significant. Finally, the initial crack widths that can be completely healed by adding EP and self-healing agents to the mortar are 200 µm and 600 µm, respectively.
Originality/value
The innovation points of this study are as follows. (1) The mechanism of the internal curing effect of EP particles on the self-healing ability of mortar cracks was revealed by crack microscopic observation tests and microscopic experiments. (2) The effect of different self-healing agent amounts on the self-healing ability of mortar cracks has been studied. (3) The effects of EP particles and self-healing agents on healing different initial widths were elucidated by crack microscopic observation tests.
Graphical abstract
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Wenqing Wu, Xin Ma, Yong Wang, Yuanyuan Zhang and Bo Zeng
The purpose of this paper is to develop a novel multivariate fractional grey model termed GM(a, n) based on the classical GM(1, n) model. The new model can provide accurate…
Abstract
Purpose
The purpose of this paper is to develop a novel multivariate fractional grey model termed GM(a, n) based on the classical GM(1, n) model. The new model can provide accurate prediction with more freedom, and enrich the content of grey theory.
Design/methodology/approach
The GM(α, n) model is systematically studied by using the grey modelling technique and the forward difference method. The optimal fractional order a is computed by the genetic algorithm. Meanwhile, a stochastic testing scheme is presented to verify the accuracy of the new GM(a, n) model.
Findings
The recursive expressions of the time response function and the restored values of the presented model are deduced. The GM(1, n), GM(a, 1) and GM(1, 1) models are special cases of the model. Computational results illustrate that the GM(a, n) model provides accurate prediction.
Research limitations/implications
The GM(a, n) model is used to predict China’s total energy consumption with the raw data from 2006 to 2016. The superiority of the GM(a, n) model is more freedom and better modelling by fractional derivative, which implies its high potential to be used in energy field.
Originality/value
It is the first time to investigate the multivariate fractional grey GM(α, n) model, apply it to study the effects of China’s economic growth and urbanization on energy consumption.
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Pingping Hou, Zheng Qian, Meng Xin Hu, Ji Qi Liu, Jun Zhang, Wei Zhao, Xiao Li, Yong Wang, HongYan Huang and Qian Ping Ran
The purpose of this study is to explore the interfacial adhesion between superhydrophobic coatings FC-X (X = 1%, 2%, 3%, 4% and 5%) and the concrete substrate, along with the…
Abstract
Purpose
The purpose of this study is to explore the interfacial adhesion between superhydrophobic coatings FC-X (X = 1%, 2%, 3%, 4% and 5%) and the concrete substrate, along with the impact of FC-X on the water repellency characteristics of the concrete substrate.
Design/methodology/approach
One synthetic step was adopted to prepare novel F-SiO2 NP hybrid fluororesin coating. The impact of varying mass fractions of F-SiO2 NPs on the superhydrophobicity of FC-X was analyzed and subsequently confirmed through water contact angle (WCA) measurements. Superhydrophobic coatings were simply applied to the concrete substrate using a one-step spraying method. The interfacial adhesion between FC-X and the concrete substrate was analyzed using tape pasting tests and abrasion resistance measurements. The influence of FC-X on the water repellency of the concrete substrate was investigated through measurements of water absorption, impermeability and electric flux.
Findings
FC-4% exhibits excellent superhydrophobicity, with a WCA of 157.5° and a sliding angle of 2.3°. Compared to control sample, FC-X exhibits better properties, including chemical durability, wear resistance, adhesion strength, abrasion resistance, water resistance and impermeability.
Practical implications
This study offers a thorough investigation into the practical implications of enhancing the durability and water repellency of concrete substrates by using superhydrophobic coatings, particularly FC-4%, which demonstrates exceptional superhydrophobicity alongside remarkable chemical durability, wear resistance, adhesion strength, abrasion resistance, water resistance and impermeability.
Originality/value
Through the examination of the interfacial adhesion between FC-X and the concrete substrate, along with an assessment of FC-X’s impact on the water repellency of the concrete, this paper provides valuable insights into the practical application of superhydrophobic coatings in enhancing the durability and performance of concrete materials.
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