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This paper aims to review the critical technology development of avian radar system at airports.

After the origin of avian radar technology is discussed, the target characteristics of flying birds are analyzed, including the target echo amplitude, flight speed, flight height, trajectory and micro-Doppler. Four typical airport avian radar systems of Merlin, Accipiter, Robin and CAST are introduced. The performance of different modules such as antenna, target detection and tracking, target recognition and classification, analysis of bird information together determines the detection ability of avian radar. The performances and key technologies of the ubiquitous avian radar are summarized and compared with other systems, and their applications, deployment modes, as well as their advantages and disadvantages are introduced and analyzed.

The ubiquitous avian radar achieves the long-time integration of target echoes, which greatly improves detection and classification ability of the targets of birds or drones, even under strong background clutter at airport. In addition, based on the big data of bird situation accumulated by avian radar, the rules of bird activity around the airport can be mined to guide the bird avoidance work.

This paper presented a novel avian radar system based on ubiquitous digital radar technology. The authors’ experience has confirmed that this system can be effective for airport bird strike prevention and management. In the future, the avian radar system will see continued improvement in both software and hardware, as the system is designed to be easily extensible.

An interactive processing scheme is proposed to improve the target detection probability as well as the tracking performance of the radar system.

Firstly, with the spatial-correlated features extracted from the foreground and background statistical models, the thresholds were adapted to distinguish the dim small targets from clutters in the complex incoherent radar images. Then, the target trajectories were constructed with the target tracking algorithm. According to the temporal correlation with the target life cycle, the thresholding values were modified in the neighbourhood of the predicted positions to improve the detection sensitivity in these areas during the tracking process. Finally, the temporal-correlated features of the remained clutters were used to further reduce the false alarm rate.

The proposed algorithm was applied on the simulated data, as well as the image sequences obtained with the incoherent marine radars. The detection results demonstrated that the interactive algorithm could detect and track the dim small targets with relatively low false alarm rate.

The interactive processing scheme could be applied for low-altitude airspace surveillance with incoherent marine radar.

The proposed scheme outperforms the classical radar target detection algorithms and the state-of-the-art image processing algorithms for video-based surveillance.

The study aims to find potential method to enhance the stability and antioxidant activity of vitamins.

Vitamin E (VE) and β-cyclodextrin (CD) were used to prepare the VE-β-CD inclusion complex via a solution method. The yielded VE-β-CD obtained from optimal experimental conditions was characterized. The mechanism of complex formation and the properties of the complex was investigated by steady-state and time-resolved fluorescence techniques. The antioxidant activity of VE-β-CD was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and compared with pure VE.

Three experimental factors – reaction temperature (T), molar ratio of VE to β-CD (rm) and inclusion time (t) – were studied for the preparation of VE-β-CD. At experimental conditions of T = 60°C, rm = 1:3 and t = 3 h, a maximum inclusion rate of VE (78.62%) was obtained. The Fourier-transform infrared spectroscopy (FTIR) shows that VE molecule was physically encapsulated by β-CD in the yielded product. Subsequentially, the steady-state fluorescence intensity of VE was found to increase upon encapsulation by β-CD due to the hindrance of fluorescence quenching of VE molecules inside the hydrophobic cavity of β-CD, and an inclusion constant K was determined to equal 3.58 × 103 L/mol from the fluorescence results. The fluorescent observation was confirmed by time-resolved fluorescence experiment as the lifetime of VE increased with an increase in β-CD concentration.

The ability of removing radicals by VE was significantly enhanced after the formation of inclusion complex with β-CD.

Bird strike risk (BSR) evaluation is a significant part of the avian radar system worldwide installed and operated at airports. The paper aims to discuss these issues.

This paper proposed a method using the real-time avian radar data to evaluate BSR with the estimations of bird strike probability and severity. The probability estimation model considered the attributes of the relative positions of the flock and the runway, the altitude of the flock and the aircraft, the flight path of the aircraft, and the ability of the bird species to avoid collision. The severity was estimated by the combination of the Delphi method and the analytic hierarchy process (AHP), called DAHP, which took full advantage of the expert knowledge and quantitative calculation.

The model was tested successfully on the simulated data at Beijing Capital International Airport (BCIA) with three runways and real data at Beihai Fucheng Airport (BFA) with one runway.

The BSR evaluation model was specifically designed for the airports with avian radars. It enabled the airport managers to objectively evaluate the risk in real time and to take effective measures.

The proposed BSR evaluation model was constructed with the real-time features of birds and aircraft based on the DAHP framework, providing scientific guidance for aviation safety and environmental management at the airport.

Foreign object debris (FOD) poses a significant hazard to aviation safety and brings huge economic losses to the aerospace industry due to aircraft damage and out‐of‐service delays. Different schemes and sensors have been utilized for FOD detection. This paper aims to look into a video‐based FOD detection system for airport runway security and propose a scheme for FOD surveillance network establishment.

The FOD detection algorithm for the system is analyzed in detail, including four steps of pre‐processing, background subtraction, post‐processing and FOD location.

The overall algorithm is applied to two sets of live video images. The results show that the algorithm is effective for FOD targets of different shades under different lighting conditions. The proposed system is also evaluated by the ground‐truth data collected at Nanyang Airport.

The runway security can be greatly increased by designing an affordable video‐based FOD detection system.

The paper presents critical techniques of video‐based FOD detection system. The scheme for FOD surveillance network, as a significant part of aviation risk management at airports, is applicable and extensible.

Incoherent primary radar is an applicable means for security surveillance of low-altitude airspace. An experimental airspace surveillance radar system has been developed for such applications. Target detector based on radar images is a powerful technique for the system. The main difficulty in designing such a detector is the rejection of heavy edge clutter for the plane position indicator (PPI) radar images after background subtraction.

The paper proposes an edge clutter rejection (ECR) detector with spatial characteristics to detect target instead of sheer threshold segmentation.

The paper chooses the optimal parameter values for the ECR detector and compares it with the existing techniques. Detection results show that the proposed detector achieves higher probability of detection with low false alarm rate, outperforming the fixed-threshold detector and the popular constant false alarm rate detectors. The ECR detector also presents limited computational cost due to its concentration on the pixels detected by the fixed-threshold algorithm with low threshold.

The aviation security of low-altitude airspace can be greatly increased by designing affordable airspace surveillance radar system.

The paper presents critical techniques for clutter rejection with PPI images, which is a significant part of the surveillance system.

The purpose of this paper is to examine how the concentration of a specific customer type – governmental customer, affects the pricing of audit services in the USA.

This paper applies a standard audit pricing model by regressing audit fees on governmental customer concentration and other common determinants of audit fees. This paper also adopts an instrumental variable approach and performs propensity-score matched sample analyzes to mitigate the potential endogeneity problem.

Using data from major customer disclosures of US publicly listed firms from 2000 to 2014, this paper finds that governmental customer concentration is positively associated with audit fees, suggesting that a higher level of governmental customer concentration increases a firm’s audit risks and audit effort. In addition, this paper performs cross-sectional analyzes and show that the association between governmental customer concentration and audit fees is more pronounced for firms with weak internal governance, weak external monitoring and high financial risks.

This paper furthers the understanding of the interactive relationships in supply chain systems and adds new evidence to the literature on customer concentration. Prior studies on customer concentration typically treat all customer types in a uniform manner. To the knowledge, this is the first study that separates governmental customers from other types of customers in an audit pricing setting. The findings highlight the importance of examining governmental customer concentration when assessing a firm’s audit risks and audit fees.

This study aims to explore the switching behaviour of short video (SV) users and its influencing factors and promote the sustainable development of SV platforms (SVPs) and the marketing strategy formulation of library and information institutions.

Using the qualitative research method of semi-structured interviews and grounded theory, this study conducts an exploratory study on the user switching phenomenon of an SVP. The authors encoded the interview text at three levels, extracted the factors influencing user switching behaviour on an SVP and constructed the corresponding theoretical model.

This study identifies the following major internal and external factors influencing user switching behaviour of SVP: platform quality, social environment, individual characteristics and use needs. It also elaborates on the impact of these internal and external factors on user switching behaviour.

This study explored the factors influencing SV user switching behaviour and constructed corresponding theoretical models, enriching research in information technology and social media switching. In practice, this study helped the existing SVPs and library and information institutions establish a corresponding early warning mechanism to prevent the loss of existing users and attract new users.

This paper aims to shed some light on the history of the Chinese videogames industry, to document the growth of the leading companies and reveal how they have been morphing into platforms delivering constellations of apps and digital content (audiovisual, films, music, literature, video streaming […]). The paper tracks the development of digital services through the prism of videogames thereby showing how this industry emerged out of the deployment of the internet.

The paper provides an overview and a synthesis of what is known about the Chinese game industry, particularly based on consultancy documents and publications from firms. The paper is based on desk research, a review of literature and trade press and the analysis of the annual reports of the leading players (NetEase, Tencent […]).

The rise of videogames and the creation of specific company’s “ecosystems” illustrate the capacity of the industry to innovate and its significance for the Chinese economy. It reveals that gaming has been a cornerstone of many Chinese technology companies. The (young) companies came up with the innovative business models (FTP, virtual items) that were required to further expand the market. They found new ways to interact with their customers through communities and various tools.

The paper relies on consultancy documents and publications from firms on heterogeneous data from industry and consultants. This approach comes with some limitations from a methodological viewpoint. It allows documenting the historical trends and describing the industrial landscape but not to qualify the relationships among players. Besides, the use of these sources leads to a greater focus on business models and a more limited one on the policy dimension. The latter is often perceived only through the glasses of the companies.

The data provided are meant to be useful to become familiar with the Chinese games industry.

The paper indicates that the online game industry is a complex web of activities with tensions and contradictions between stakeholders (industry, government and consumers). In the case of China, there is a conflict between the willingness to liberalize the economy and the will to maintain an ideological monopoly through cultural industries.

Little research has been devoted to the role of videogames in emerging economies, to its specific features and to the relationships with the media industry and the information and communications technology sector. The contribution of this “digital native” to the production and distribution of digital content remains less studied. The paper provides an up-to-date overview of the Chinese case.

The purpose of this paper is to examine a Chinese indigenous concept of organizational ownership behavior (OOB) as an aspect of employee suzhi in relation to organizational citizenship behavior (OCB) in the Western context.

A content analysis based on a review of related research in Western mainstream and Chinese domestic literature is conducted.

Suzhi at the organizational level can be linked to the construct of OCB. In Chinese organizations, a relevant concept to OCB can be better understood as OOB to capture the sociopolitical and cultural context unique to Chinese organizations. The dimensional structure of OOB is presented to differentiate it from OCB which is popular in the Western context.

The identified construct of OOB offers important implications for indigenous Chinese management research and human resources management (HRM) practice. OOB, based on Chinese management practice, can better conform to China’s unique historical and cultural context and management practices. This concept varies distinctively from Western OCB in terms of its connotation and dimensions.

The concept of OOB as an indigenous employee organizational behavior in the Chinese context is conceptualized. The paper differentiates the OOB construct from OCB and presents an initial set of six dimensions of OOB for future research.