Shuang Han, Jing Zhang, Quanyue Yang, Zijian Yuan, Shubin Li, Fengying Cui, Chuntang Zhang and Tao Wang
The performance of the classical car-following system is easily affected by external disturbances. To enhance the performance of the classical car-following model under sudden…
Abstract
Purpose
The performance of the classical car-following system is easily affected by external disturbances. To enhance the performance of the classical car-following model under sudden external disturbances, a novel car-following model is established to smooth traffic flow.
Design/methodology/approach
This paper proposed a Proportion Integration Differentiation (PID) control strategy based on classical control theory and developed a novel car-following model. The linear system theory and Laplace transform are used to derive a closed-loop transfer function. Then, the stability condition is obtained by using the Routh stability criterion and the small gain theorem. Finally, the validity and feasibility of the PID control strategy is proved by numerical simulations.
Findings
The analytic results and the numerical simulation results show that both the integration part and the differential part have the positive effect to suppress traffic oscillation efficiently; the collaboration of these two parts has more power to improve the stability of traffic flow. It means that the proposed model integrated with the PID control strategy has the ability of anti-interference and smooth traffic compared with the classical car-following model.
Originality/value
This paper introduces the PID control strategy into the classical car-following system, which enhances the stability of the system and also provides an efficient method for optimizing the traffic flow system.
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Dengdeng Wanyan and Zijian Wang
This article aims to provide reference for government departments and public cultural institutions in strengthening the provision of public cultural services for low-income…
Abstract
Purpose
This article aims to provide reference for government departments and public cultural institutions in strengthening the provision of public cultural services for low-income groups, improving services methods and fostering their cultural awareness and cultural rights.
Design/methodology/approach
Evidence from an empirical study on representative small and medium-sized cities.
Findings
This paper defines the specific aspects of the difficulties faced by urban low-income people in obtaining public cultural services, and it is no longer limited to analyze the causes behind these difficulties from a specific perspective.
Originality/value
The difficulties faced by urban low-income people in obtaining public cultural services are mainly reflected in the following four aspects: external condition pressure, individual condition limitations, service supply difference and feedback mechanism failure.
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Zijian Wang, Ximing Xiao, Shiwei Fu and Qinggong Shi
This study aims to uncover the mechanisms behind the marginalization of county-level public libraries.
Abstract
Purpose
This study aims to uncover the mechanisms behind the marginalization of county-level public libraries.
Design/methodology/approach
The research surveyed 25 counties in central China, including Hubei, Chongqing, Hunan, and Guizhou provinces. Semi-structured interviews were conducted with library directors and deputy directors, focusing on main and branch library construction, cultural inclusivity, library assessment, and digital services.
Findings
Contributing factors to library marginalization were identified as economic pressure, institutional domain, longstanding issues, organizational entity, and societal misconceptions. Building on this, the study introduces the HBAC model to explain county-level public library marginalization. Considering the actual social context of these libraries, the article proposes a “3 + 1” approach to mitigate their marginalization.
Originality/value
The research methodology, analysis process, theoretical model, and recommendations provided could shed light on academic research and practical exploration in the field of public libraries globally.
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Linhao Ouyang, Zijian Zhang, Xiaoling Huang and Shi Xie
The purpose of this study is to restore the spatial distribution of overseas remittance businesses in Shantou during the 1940s. It explores various socioeconomic factors that…
Abstract
Purpose
The purpose of this study is to restore the spatial distribution of overseas remittance businesses in Shantou during the 1940s. It explores various socioeconomic factors that influenced the concentration of local remittance business investment in real estate. By reconstructing the spatial distribution of remittance business activities in Shantou, this study hopes to lay a foundation for further analysis of the business strategies of Chaoshan merchants.
Design/methodology/approach
This research draws on information from the published Swatow Guide, archival sources and cadastral maps to identify the location of remittance enterprises and the native place and overseas networks of property owners.
Finding
This study reveals that the spatial distribution of the remittance enterprises was determined by the native place origins of local property owners, and that the inflow of overseas Chinese capital contributed to real estate development in Shantou.
Research limitations/implications
Despite the limited access to Chinese official archives, this paper manages to identify several building blocks and neighbors in Shantou for spatial analysis.
Practical implications
This study is the first attempt to use the geographical information system (GIS) method in Chinese urban history research and hopes to establish a larger historical database of Shantou as a sample for comparison.
Originality/value
This investigation advances the spatial study of urban history and overseas Chinese remittances in the maritime society of South China.
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Zijian Cheng, Zhangxin (Frank) Liu and Jiaxin Xie
Does the choice of listing process matter in determining a firm's future crash risk? It is understood that the main function of an equity market is to provide price discovery…
Abstract
Purpose
Does the choice of listing process matter in determining a firm's future crash risk? It is understood that the main function of an equity market is to provide price discovery, however, it is not clear whether the choice of listing methods would matter to the shareholders' wealth in the long term. We are the first to answer this question by utilising a hand-collected dataset that identifies all companies that went public via reverse merger (RM) in a growing emerging market.
Design/methodology/approach
Using hand-collected data from 2000 to 2018 in China, we follow the literature to construct two crash risk measures for RM and IPO firms. Our main analysis is performed using OLS regressions on the full sample as well as a sample using Propensity Score Matching. Our results hold with a number of robustness checks.
Findings
We find that reverse merger (RM) firms exhibit higher future stock price crash risk than initial public offering (IPO) firms. This relationship is more predominant in non-state-owned enterprises, and we find weak evidence suggesting such relationship weakens as firms stay longer in the market. There is no significant difference in future stock price crash risk between RM firms listed during IPO suspension periods and normal IPO firms.
Originality/value
We are the first to study the choice of listing method and its impact on firms' future stock price crash risk.
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Qiang Zhang, Zijian Ye, Siyu Shao, Tianlin Niu and Yuwei Zhao
The current studies on remaining useful life (RUL) prediction mainly rely on convolutional neural networks (CNNs) and long short-term memories (LSTMs) and do not take full…
Abstract
Purpose
The current studies on remaining useful life (RUL) prediction mainly rely on convolutional neural networks (CNNs) and long short-term memories (LSTMs) and do not take full advantage of the attention mechanism, resulting in lack of prediction accuracy. To further improve the performance of the above models, this study aims to propose a novel end-to-end RUL prediction framework, called convolutional recurrent attention network (CRAN) to achieve high accuracy.
Design/methodology/approach
The proposed CRAN is a CNN-LSTM-based model that effectively combines the powerful feature extraction ability of CNN and sequential processing capability of LSTM. The channel attention mechanism, spatial attention mechanism and LSTM attention mechanism are incorporated in CRAN, assigning different attention coefficients to CNN and LSTM. First, features of the bearing vibration data are extracted from both time and frequency domain. Next, the training and testing set are constructed. Then, the CRAN is trained offline using the training set. Finally, online RUL estimation is performed by applying data from the testing set to the trained CRAN.
Findings
CNN-LSTM-based models have higher RUL prediction accuracy than CNN-based and LSTM-based models. Using a combination of max pooling and average pooling can reduce the loss of feature information, and in addition, the structure of the serial attention mechanism is superior to the parallel attention structure. Comparing the proposed CRAN with six different state-of-the-art methods, for the predicted results of two testing bearings, the proposed CRAN has an average reduction in the root mean square error of 57.07/80.25%, an average reduction in the mean absolute error of 62.27/85.87% and an average improvement in score of 12.65/6.57%.
Originality/value
This article provides a novel end-to-end rolling bearing RUL prediction framework, which can provide a reference for the formulation of bearing maintenance programs in the industry.