Hui Guo, Jinzhou Jiang, Suoting Hu, Chun Yang, Qiqi Xiang, Kou Luo, Xinxin Zhao, Bing Li, Ziquan Yan, Liubin Niu and Jianye Zhao
The bridge expansion joint (BEJ) is a key device for accommodating spatial displacement at the beam end, and for providing vertical support for running trains passing over the gap…
Abstract
Purpose
The bridge expansion joint (BEJ) is a key device for accommodating spatial displacement at the beam end, and for providing vertical support for running trains passing over the gap between the main bridge and the approach bridge. For long-span railway bridges, it must also be coordinated with rail expansion joint (REJ), which is necessary to accommodate the expansion and contraction of, and reducing longitudinal stress in, the rails. The main aim of this study is to present analysis of recent developments in the research and application of BEJs in high-speed railway (HSR) long-span bridges in China, and to propose a performance-based integral design method for BEJs used with REJs, from both theoretical and engineering perspectives.
Design/methodology/approach
The study first presents a summary on the application and maintenance of BEJs in HSR long-span bridges in China representing an overview of their state of development. Results of a survey of typical BEJ faults were analyzed, and field testing was conducted on a railway cable-stayed bridge in order to obtain information on the major mechanical characteristics of its BEJ under train load. Based on the above, a performance-based integral design method for BEJs with maximum expansion range 1600 mm (±800 mm), was proposed, covering all stages from overall conceptual design to consideration of detailed structural design issues. The performance of the novel BEJ design thus derived was then verified via theoretical analysis under different scenarios, full-scale model testing, and field testing and commissioning.
Findings
Two major types of BEJs, deck-type and through-type, are used in HSR long-span bridges in China. Typical BEJ faults were found to mainly include skewness of steel sleepers at the bridge gap, abnormally large longitudinal frictional resistance, and flexural deformation of the scissor mechanisms. These faults influence BEJ functioning, and thus adversely affect track quality and train running performance at the beam end. Due to their simple and integral structure, deck-type BEJs with expansion range 1200 mm (± 600 mm) or less have been favored as a solution offering improved operational conditions, and have emerged as a standard design. However, when the expansion range exceeds the above-mentioned value, special design work becomes necessary. Therefore, based on engineering practice, a performance-based integral design method for BEJs used with REJs was proposed, taking into account four major categories of performance requirements, i.e., mechanical characteristics, train running quality, durability and insulation performance. Overall BEJ design must mainly consider component strength and the overall stiffness of BEJ; the latter factor in particular has a decisive influence on train running performance at the beam end. Detailed BEJ structural design must stress minimization of the frictional resistance of its sliding surface. The static and dynamic performance of the newly-designed BEJ with expansion range 1600 mm have been confirmed to be satisfactory, via numerical simulation, full-scale model testing, and field testing and commissioning.
Originality/value
This research provides a broad overview of the status of BEJs with large expansion range in HSR long-span bridges in China, along with novel insights into their design.
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Yangsheng Ye, Degou Cai, Lin Geng, Hongye Yan, Junkai Yao and Feng Chen
This study aims to propose a semiempirical and semitheoretical cyclic compaction constitutive model of coarse-grained soil filler for the high-speed railway (HSR) subgrade under…
Abstract
Purpose
This study aims to propose a semiempirical and semitheoretical cyclic compaction constitutive model of coarse-grained soil filler for the high-speed railway (HSR) subgrade under cyclic load.
Design/methodology/approach
According to the basic framework of critical state soil mechanics and in view of the characteristics of the coarse-grained soil filler for the HSR subgrade to bear the train vibration load repeatedly for a long time, the hyperbolic empirical relationship between particle breakage and plastic work was derived. Considering the influence of cyclic vibration time and stress ratio, the particle breakage correction function of coarse-grained soil filler for the HSR subgrade under cyclic load was proposed. According to the classical theory of plastic mechanics, the shearing dilatation equation of the coarse-grained soil filler for the HSR subgrade considering particle breakage was modified and obtained. A semiempirical and semitheoretical cyclic compaction constitutive model of coarse-grained soil filler for the HSR subgrade under cyclic load was further established. The backward Euler method was used to discretize the constitutive equation, build a numerical algorithm of “elastic prediction and plastic modification” and make a secondary development of the program to solve the cyclic compaction model.
Findings
Through the comparison with the result of laboratory triaxial test under the cyclic loading of coarse-grained soil filler for the HSR subgrade, the accuracy and applicability of the cyclic compaction model were verified. Results show that the model can accurately predict the cumulative deformation characteristics of coarse-grained soil filler for the HSR subgrade under the train vibration loading repeatedly for a long time. It considers the effects of particle breakage and stress ratio, which can be used to calculate and analyze the stress and deformation evolution law of the subgrade structure for HSR.
Originality/value
The research can provide a simple and practical method for calculating deformation of railway under cyclic loading.
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The deformation of the roadbed is easily influenced by the external environment to improve the accuracy of high-speed railway subgrade settlement prediction.
Abstract
Purpose
The deformation of the roadbed is easily influenced by the external environment to improve the accuracy of high-speed railway subgrade settlement prediction.
Design/methodology/approach
A high-speed railway subgrade settlement interval prediction method using the secretary bird optimization (SBOA) algorithm to optimize the BP neural network under the premise of gray relational analysis is proposed.
Findings
Using the SBOA algorithm to optimize the BP neural network, the optimal weights and thresholds are obtained, and the best parameter prediction model is combined. The data were collected from the sensors deployed through the subgrade settlement monitoring system, and the gray relational analysis is used to verify that all four influencing factors had a great correlation to the subgrade settlement, and the collected data are verified using the model.
Originality/value
The experimental results show that the SBOA-BP model has higher prediction accuracy than the BP model, and the SBOA-BP model has a wider range of prediction intervals for a given confidence level, which can provide higher guiding value for practical engineering applications.
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Rodrigo Soares Santana, Gustavo Hermínio Salati Marcondes de Moraes and Hermes Moretti Ribeiro da Silva
This study aims to evaluate the influence of factors attributed to relationship attractiveness between supplier and customer, from the supplier’s perspective.
Abstract
Purpose
This study aims to evaluate the influence of factors attributed to relationship attractiveness between supplier and customer, from the supplier’s perspective.
Design/methodology/approach
The empirical exercise was based on the use of multivariate data analysis with confirmatory factor analysis and a partial least squares approach to structural equation modeling.
Findings
The study resulted in a robust model, with a high explanatory factor for the latent variable relational attractiveness and commitment was the most influential factor, followed by expected value and interorganizational trust.
Research limitations/implications
Some limitations of the study can be highlighted: conducting research in a single cooperative and with a single audience; choosing a short-cycle supply chain, which may make it difficult to generalize to other industries; the cross-section nature of data also hinders the analysis to understand how the association between variables of interest may vary over time.
Practical implications
The negative influence of interpersonal trust reinforces the importance of developing collaborative attitudes between parties, whereas the non-significant value for dependence (financial and volume dependence) shows this is not a risk factor for relational attractiveness in a supply chain. Such results provide evidence on how to develop relationship management between suppliers and customers that are part of the same supply chain.
Social implications
It offers a new perspective for research in cooperatives, which still have no consensus on the motivating factors for members’ participation, including as evidence the results of the largest flower producing center in Latin America. The more a cooperative succeeds in increasing relational attractiveness, the greater the cooperative power and the ability to adapt to shocks and changes, which are fundamental factors for the success and longevity of the cooperative.
Originality/value
The research presents a model that is comprehensive enough to fit in different contexts and consider its specific characteristics. Additionally, this paper has added in-depth information on the relational attractiveness relationships in the context of a developing country.
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Yanmin Zhou, Zheng Yan, Ye Yang, Zhipeng Wang, Ping Lu, Philip F. Yuan and Bin He
Vision, audition, olfactory, tactile and taste are five important senses that human uses to interact with the real world. As facing more and more complex environments, a sensing…
Abstract
Purpose
Vision, audition, olfactory, tactile and taste are five important senses that human uses to interact with the real world. As facing more and more complex environments, a sensing system is essential for intelligent robots with various types of sensors. To mimic human-like abilities, sensors similar to human perception capabilities are indispensable. However, most research only concentrated on analyzing literature on single-modal sensors and their robotics application.
Design/methodology/approach
This study presents a systematic review of five bioinspired senses, especially considering a brief introduction of multimodal sensing applications and predicting current trends and future directions of this field, which may have continuous enlightenments.
Findings
This review shows that bioinspired sensors can enable robots to better understand the environment, and multiple sensor combinations can support the robot’s ability to behave intelligently.
Originality/value
The review starts with a brief survey of the biological sensing mechanisms of the five senses, which are followed by their bioinspired electronic counterparts. Their applications in the robots are then reviewed as another emphasis, covering the main application scopes of localization and navigation, objection identification, dexterous manipulation, compliant interaction and so on. Finally, the trends, difficulties and challenges of this research were discussed to help guide future research on intelligent robot sensors.
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Marcielle Anzilago and Ilse Maria Beuren
This study aims to analyze the effects of interorganizational cost management and opportunism on the reflexes of relational norms on satisfaction with interorganizational…
Abstract
Purpose
This study aims to analyze the effects of interorganizational cost management and opportunism on the reflexes of relational norms on satisfaction with interorganizational cooperation in franchised companies. The collective synergy arising from these relationships mainly seeks to increase competitiveness and commercial development. Windolph and Moeller observed that interorganizational cost management increases satisfaction in the relationship with partners, while relational norms attenuate the negative effect on supplier satisfaction.
Design/methodology/approach
A survey was carried out with managers of franchised companies in the food industry. The managers were identified on the social network Linkedin. After that, an invitation was sent to participate in the research. A total of 88 valid responses were obtained. The questionnaire consists of 40 extracted assertions. A pre-test was carried out to verify the comprehensibility of the wording of the assertions. Structural equation modeling with partial least squares (PLS-SEM) was used for data analysis. For analysis, validation and adequacy tests of the model were carried out, and executed in the software SmartPLS.
Findings
Survey results reveal that interorganizational cost management increases franchisor relationship satisfaction. Relational social norms mitigate the negative effect of opportunism on satisfaction with cooperation. And interorganizational cost management plays an important role in the relationship between relational norms and satisfaction with cooperation between franchisor and franchisees.
Research limitations/implications
However, limitations resulting from the methodological design of the research must be considered in the interpretation of the results, at the same time that they provide opportunities for new research. As for the methodological aspects, the study cannot be generalized to other branches of companies, because it is a sector with franchises with specific characteristics. It should also be considered that the study was limited to investigating the proposed model, but other constructs can be observed in the literature. Finally, to empirically assess the constructs of the theoretical model, research instruments from studies other than those considered here can be used.
Practical implications
This study contributes with relevant literature and the management practice of interorganizational cooperation by empirically demonstrating the importance of interorganizational cost management as a management control mechanism and to mitigate the effects of opportunism between franchisor and franchisees.
Social implications
It also contributes to the inclusion of social norms in the relationship between franchisor and franchisees with a view to increasing franchisee satisfaction with their franchisor, which also aims to mitigate the impacts of opportunism in this relationship. It contributes to the social order, as they reveal ways to mitigate possible conflicts between franchisor and franchisee and generate greater transparency in the relationship.
Originality/value
This study is justified by the fact that it investigates relational aspects of cooperation between franchisor and franchisees, a form of interorganizational cooperation that is growing in the market. It is also justified by highlighting the importance of interorganizational cost management as a means of mitigating the opportunistic effects between franchisor and franchisees, proving to be an important management mechanism. Research is especially important because interorganizational strategies have been spreading in corporate environments (Dekker, Ding & Groot, 2016) and the maintenance of the relationship is dependent on satisfaction with cooperation.
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Danusa Silva da Costa, Lucely Nogueira dos Santos, Nelson Rosa Ferreira, Katiuchia Pereira Takeuchi and Alessandra Santos Lopes
The aim was not to perform a systematic review but firstly to search in PubMed, Science Direct, Scopus and Web of Science databases on the papers published in the last five years…
Abstract
Purpose
The aim was not to perform a systematic review but firstly to search in PubMed, Science Direct, Scopus and Web of Science databases on the papers published in the last five years using tools for reviewing the statement of preferred information item for systematic reviews without focusing on a randomized analysis and secondly to perform a bibliometric analysis on the properties of films and coatings added of tocopherol for food packaging.
Design/methodology/approach
On January 24, 2022, information was sought on the properties of films and coatings added of tocopherol for use as food packaging published in PubMed, Science Direct, Scopus and Web of Science databases. Further analysis was performed using bibliometric indicators with the VOSviewer tool.
Findings
The searches returned 33 studies concerning the properties of films and coatings added of tocopherol for food packaging, which were analyzed together for a better understanding of the results. Data analysis using the VOSviewer tool allowed a better visualization and exploration of these words and the development of maps that showed the main links between the publications.
Originality/value
In the area of food science and technology, the development of polymers capable of promoting the extension of the shelf life of food products is sought, so the knowledge of the properties is vital for this research area since combining a biodegradable polymeric material with a natural antioxidant active is of great interest for modern society since they associate environmental preservation with food preservation.
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Shunsuke Managi, Jingyu Wang and Lulu Zhang
The purpose of this paper is to provide the extensive review on dynamic monitoring of forestry area in China.
Abstract
Purpose
The purpose of this paper is to provide the extensive review on dynamic monitoring of forestry area in China.
Design/methodology/approach
Countermeasure and suggestions were proposed for three aspects including the establishment of data sets with unified standards, top-level design of monitoring and assessment and analysis models, and establishment of the decision support platform with multiple scenario simulation.
Findings
Finally, the authors proposed key research area in this field, i.e., improving the systematic and optimal forest management through integrating and improving the data, models and simulation platforms and coupling the data integration system, assessment system and decision support system.
Originality/value
The authors explored the limitation of dynamic monitoring and state of the art research on data accumulation, professional model development and the analytical platform.
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Yang Li, Yaochen Qin, Liqun Ma and Ziwu Pan
The ecological environment of the Loess Plateau, China, is extremely fragile under the context of global warming. Over the past two decades, the vegetation of the Loess Plateau…
Abstract
Purpose
The ecological environment of the Loess Plateau, China, is extremely fragile under the context of global warming. Over the past two decades, the vegetation of the Loess Plateau has undergone great changes. This paper aims to clarify the response mechanisms of vegetation to climate change, to provide support for the restoration and environmental treatment of vegetation on the Loess Plateau.
Design/methodology/approach
The Savitsky–Golay (S-G) filtering algorithm was used to reconstruct time series of moderate resolution imaging spectroradiometer (MODIS) 13A2 data. Combined with trend analysis and partial correlation analysis, the influence of climate change on the phenology and enhanced vegetation index (EVI) during the growing season was described.
Findings
The S-G filtering algorithm is suitable for EVI reconstruction of the Loess Plateau. The date of start of growing season was found to gradually later along the Southeast–Northwest direction, whereas the date of the end of the growing season showed the opposite pattern and the length of the growing season gradually shortened. Vegetation EVI values decreased gradually from Southeast to Northwest. Vegetation changed significantly and showed clear differentiation according to different topographic factors. Vegetation correlated positively with precipitation from April to July and with temperature from August to November.
Originality/value
This study provides technical support for ecological environmental assessment, restoration of regional vegetation coverage and environmental governance of the Loess Plateau over the past two decades. It also provides theoretical support for the prediction model of vegetation phenology changes based on remote sensing data.
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Debolina Halder Adhya, Eesa M. Al Bastaki, Sara Suleymanova, Nasiruddeen Muhammad and Arunprasad Purushothaman
The COVID-19 pandemic has compelled higher education institutions (HEI) in the United Arab Emirates (UAE) and globally to shift to a new pedagogy that is sustainable and resilient…
Abstract
Purpose
The COVID-19 pandemic has compelled higher education institutions (HEI) in the United Arab Emirates (UAE) and globally to shift to a new pedagogy that is sustainable and resilient to crises and disruptions. It necessitated the integration of technologies as part of pedagogical innovation and modification of higher education practices – advancing toward a more holistic integration of physical and digital tools and methods to enable more flexible, creative, collaborative and participatory learning. In terms of pedagogy, an open approach to learning is essential, combining in-person teaching with technological tools and online learning.
Design/methodology/approach
This paper examines theoretical and empirical literature to define the potential benefits of utilizing open educational practices (OEP) in higher education, including better access, furthering equity and enhancing teaching, learning and assessment.
Findings
It proposes a comprehensive framework built on a continuum of open pedagogy (OP) that comprises “Emphasis”, “Essentials” and “Evolution”. Based on this framework, a set of recommendations for using OEP for successful knowledge building is provided.
Originality/value
The research determined the significance of increased OEP involvement for sustainable learning possibilities and the UAE’s initiatives in developing educators to support innovative pedagogies and technology-enabled teaching-learning standards. The study suggests placing more emphasis on faculty and student scaffolding while using OP for better learning experiences and outcomes, as well as more institutional support and the need for policy development to transform the UAE into a global hub for sustainable education.