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This paper aims to study a disturbance rejection controller to improve the anti-interference capability and the position tracking performance of airborne radar stabilized platform that ensures the stability and clarity of synthetic aperture radar imaging.

This study proposes a disturbance rejection control scheme for an airborne radar stabilized platform based on the active disturbance rejection control (ADRC) inverse estimation algorithm. Exploiting the extended state observer (ESO) characteristic, an inversely ESO is developed to inverse estimate the unmodeled state and extended state of the platform system known as total disturbances, which greatly improves the estimation performance of the disturbance. Then, based on the inverse ESO result, feedback the difference between the output of the tracking differentiator and the inverse ESO result to the nonlinear state error feedback controller (NLSEF) to eliminate the effects of total disturbance and ensure the stability of the airborne radar stabilized platform.

Simulation experiments are adopted to compare the performance of the ADRC inverse estimation algorithm with that of the proportional integral derivative controller which is one of the mostly applied control schemes in platform systems. In addition, classical ADRC is compared as well. The results have shown that the ADRC inverse estimation algorithm has a better disturbance rejection performance when disturbance acts in airborne radar stabilized platform, especially disturbed by continuous airflow under some harsh air conditions.

The originality of this paper is exploiting the ESO characteristic to develop an inverse ESO, which greatly improves the estimation performance of the disturbance. And the ADRC inverse estimation algorithm is applied to ameliorate the anti-interference ability of the airborne radar stabilization platform, especially the ability to suppress continuous interference under complex air conditions.

This study aims to investigate the acoustic roughness of rails on China’s high-speed railways, with a focus on short-wavelength irregularities (less than 80 cm), which are known to significantly contribute to noise. The goal is to develop a specific acoustic roughness spectrum tailored for China’s high-speed railway system, as no such spectrum currently exists.

A long-term tracking study was conducted on major railway lines in China, monitoring rail roughness throughout the initial operational period and the rails’ service life. Data preprocessing techniques such as peak removal and curvature correction were applied for acoustic adjustments. A spatial-wavelength domain transformation was performed, providing the distribution patterns and statistical characteristics of acoustic roughness on China’s high-speed rails. Based on these analyses, a model for constructing the acoustic roughness spectrum was developed.

The study found that the acoustic roughness of China’s high-speed railway rails follows a χ² distribution with six degrees of freedom. For wavelengths greater than 8 cm, the acoustic roughness spectrum remains below the ISO specified limits. In the wavelength range of 3.2 cm to 6.3 cm, the roughness is comparable to or within the limits specified by ISO 3095:2005 and ISO 3095:2013. However, for wavelengths shorter than 2.5 cm, the roughness exceeds ISO limits.

This research fills the gap in the lack of a specific acoustic roughness spectrum for China’s high-speed railways. By establishing a tailored spectrum based on long-term data analysis, the findings provide valuable insights for noise control and rail maintenance in the context of China’s high-speed rail system.

This paper aims to improve the anti-interference ability of the airborne radar stabilization platform, especially the ability to suppress continuous disturbance under complex air conditions to ensure the clarity and stability of airborne radar imaging.

This paper proposes a new active disturbance rejection control (ADRC) strategy based on the cascade extended state observer (ESO) for airborne radar stabilization platform, which adopts two first-order ESOs to estimate the angular velocity value and the angular position value of the stabilized platform. Then makes the error signal which subtracts the estimated value of ESO from the output signal of the tracking-differentiator as the input signal of the nonlinear state error feedback (NLSEF), and according to the output signal of the NLSEF and the value which dynamically compensated the total disturbances estimated by the two ESO to produce the final control signal.

The simulation results show that, compared with the classical ADRC, the ADRC based on the cascade ESO not only estimates the unknown disturbance more accurately but also improves the delay of disturbance observation effectively due to the increase of the order of the observer. In addition, compared with the classical PID control and the classical ADRC, it has made great progress in response performance and anti-interference ability, especially in the complex air conditions.

The originality of the paper is the adoption of a new ADRC control strategy based on the cascade ESO to ameliorate the anti-interference ability of the airborne radar stabilization platform, especially the ability to suppress continuous interference under complex air conditions.

The purpose of this paper is to describe how people in a coastal community act upon anxieties about overexploitation of a shared resource and their attempts to ease the moral tension caused by the rapid industrialization of their fishery. This anthropological study contributes to the cross-disciplinary discussion of community-based resource management.

The study is based on ethnographic fieldwork done at the Nanfang'ao port located in northeastern Taiwan. This port has several prosperous offshore fisheries including a mackerel fishery. The mackerel fishery has undergone important transformations in recent decades. The first was a total transformation of fishing methods in 2013. The second was the government's formulation of the “Regulations for Fishing Vessels Catching Mackerels and Jacks,” implemented in 2014. This research illustrates how people in a community take various approaches to pursue sustainability for the human beings and the more-than-human world.

In Nanfang'ao port, local people have developed a meaningful cultural festival through the integration of various symbols and rituals from different contexts in an effort to call attention to moral issues associated with the mackerel fishery.

This research contributes to the discussion on community resource management of marine fishery.

This study aims to examine the evolution of spatial–temporal patterns in China’s hotel industry from 1978 to 2018.

A database comprising over 140,000 hotels with more than 30 rooms was created. The exploratory spatial–temporal data analysis (ESTDA) method, based on space–time cube model, was used to explore and visualize the spatial–temporal pattern of hotels.

The Chinese hotel industry can be divided into two development stages, namely, a large hotel-dominant stage before 2000 and a small–medium-sized hotel-dominant stage after 2000. China’s prefecture-level cities were clustered into four tiers. The higher the tier, the earlier the city will initiate hotel development. The Chinese hotel industry has four continuous hotspots (the Yangtze River Delta, Pearl River Delta, Bohai Rim and Sichuan and Chongqing) and some temporary hotspots.

This study lacks quantitative investigation, which could show the underlying mechanism of the evolution of the Chinese hotel industry.

This study is the first to investigate China’s hotel evolution over 40 years by applying big data and the ESTDA method. The systematic and evolutionary exploration will enable hotel researchers to understand the spatial–temporal nature of hotel distribution better. Introducing the ESTDA method into tourism and hotel research also provides an additional tool to researchers. Hotel investors and operators, city and tourism planners and market regulators can learn from the evolution of location patterns to make better where and when decisions.

This paper aims to provide an in-depth analysis of the process of standards setting based on the case of long-term evolution time division duplex (LTE TDD) deployment in China.

Using actor-network theory (ANT) as a theoretical framework, multi-level analyses are presented to explain the process of adoption of LTE TDD at a global level.

Findings identified the complex interaction between the social and technical aspects of fourth-generation (4G) by highlighting the co-evolving nature, diversity and interface that constitute the next-generation network environment.

ANT provides a framework of ideas for describing the process of technology adoption and for developing stories that explain it.

The findings shed light on a critical insight of the interrelationships between TD-SCDMA and LTE TDD and identify the policy successes and failures of 4G mobile networks.

Research in the area of technology‐enhanced learning (TEL) throughout the last decade has largely focused on sharing and reusing educational resources and data. This effort has led to a fragmented landscape of competing metadata schemas, or interface mechanisms. More recently, semantic technologies were taken into account to improve interoperability. The linked data approach has emerged as the de facto standard for sharing data on the web. To this end, it is obvious that the application of linked data principles offers a large potential to solve interoperability issues in the field of TEL. This paper aims to address this issue.

In this paper, approaches are surveyed that are aimed towards a vision of linked education, i.e. education which exploits educational web data. It particularly considers the exploitation of the wealth of already existing TEL data on the web by allowing its exposure as linked data and by taking into account automated enrichment and interlinking techniques to provide rich and well‐interlinked data for the educational domain.

So far web‐scale integration of educational resources is not facilitated, mainly due to the lack of take‐up of shared principles, datasets and schemas. However, linked data principles increasingly are recognized by the TEL community. The paper provides a structured assessment and classification of existing challenges and approaches, serving as potential guideline for researchers and practitioners in the field.

Being one of the first comprehensive surveys on the topic of linked data for education, the paper has the potential to become a widely recognized reference publication in the area.

Despite a large amount of BIM data at the handover stage, it is still difficult to identify and effectively isolate valuable construction supply chain (CSC) data that need to be reliably handed over for operation. Moreover, the role of reconciling disparate data is usually played by one party. The integration of blockchain and BIM is a plausible framework for building a reliable digital asset lifecycle. This paper proposes a BIM single source of truth (BIMSSoT) data model using blockchain for ensuring a reliable CSC data delivery.

This paper utilises a blended methodology, the foundation of which is ingrained in business and management research with elements of information and communication technology (ICT) research wherever required. Knowledge elicitation case studies utilising novel interventions such as a data flow diagram (DFD), taxonomy and entity-relationship diagram (ERD) were used in this paper to develop the BIMSSoT data model. The model was validated using an expert forum, and its technological feasibility was established by developing a proof of concept.

The practical contribution of this research leads to the progression of BIM towards digital engineering to go beyond object-based 3D modelling by building structured and reliable datasets, transitioning from project-centric records to a digital ecosystem of linked databases by utilizing blockchain's potential for ensuring trusted data.

To the best of the author's knowledge, prior to this paper, no research had investigated a detailed data model development leveraging blockchain and BIM to integrate an immutable and complete record of CSC data as another dimension of BIM for operations.

This book chapter aimed to examine the relationships between green supply chain practices and environmental performance in Malaysian Small and Medium Enterprises (SMEs). The practices of green supply chain in achieving environmental performance have been one priority concerns in Malaysia. However, green supply chain practices adoption remains emergence.

This manuscript adopted the multiple regression analysis in investigating the green supply chain (GSC) practices and environmental performance's variables. The self-administered surveys were randomly disseminated to Malaysian SMEs and 59 responses were returned. The result theoretically ascertained the positive relationship between GSC practices and environmental performance measures.

The findings are in aligned with the Resource-Based View (RBV) theory that conceptualized the GSC practices and strategies to sustain the environmental performance within the SMEs. In a nutshell, these findings would serve as the research implications and recommendations to the scholars, industrial practitioners, and policymakers who are interested in these GSC practices and environmental performance. This would further serve as a guideline for companies that tend to implement these GSC practices for improving its environmental performance.

The research revealed that ‘eco-design and packaging’ and ‘reverse logistics’ are significant to environmental performance, but both ‘green procurement’ and ‘investment recovery’ are not significant to environmental performance. The literature gaps exhibited for this manuscript; hence, future studies should be carried out on supply chain practices and environmental performance since there is no prescriptive method in sustaining environmental performance that matches all conditions in Malaysian SMEs.

Prior research showed that danwei, the work unit, was very important in determining workers' social, economic, and political lives in pre-reform urban China. In this chapter, we argue that danwei continues to be an agent of social stratification in contemporary urban China. Using data from a 1999 survey that we conducted in three large Chinese cities, Wuhan, Shanghai, and Xi'an, we assess the extent to which workers' socioeconomic well-being depends on the financial conditions of their danwei. Results show that the financial situation of danwei remains one of the most important determinants of earnings and benefits. However, the explanatory power of danwei's financial situation is much greater for earnings than for benefits.