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  1. Article ; Online: Self-Supervised Learning for the Distinction between Computer-Graphics Images and Natural Images

    Kai Wang

    Applied Sciences, Vol 13, Iss 1887, p

    2023  Volume 1887

    Abstract: With the increasing visual realism of computer-graphics (CG) images generated by advanced rendering engines, the distinction between CG images and natural images (NIs) has become an important research problem in the image forensics community. Previous ... ...

    Abstract With the increasing visual realism of computer-graphics (CG) images generated by advanced rendering engines, the distinction between CG images and natural images (NIs) has become an important research problem in the image forensics community. Previous research works mainly focused on the conventional supervised learning framework, which usually requires a good quantity of labeled data for training. To our knowledge, we study, for the first time in the literature, the utility of the self-supervised learning mechanism for the forensic classification of CG images and NIs. The idea is to make use of a large number of readily available unlabeled data, along with a self-supervised training procedure on a well-designed pretext task for which labels can be generated in an automatic and convenient way without human manual labeling effort. Differing from existing self-supervised methods, based on pretext tasks targeted at image understanding, or based on contrastive learning, we propose carrying out self-supervised training on a forensics-oriented pretext task of classifying authentic images and their modified versions after applying various manipulations. Experiments and comparisons showed the effectiveness of our method for solving the CG forensics problem under different evaluation scenarios. Our proposed method outperformed existing self-supervised methods in all experiments. It could sometimes achieve comparable, or better, performance. compared with a state-of-the-art fully supervised method under difficult evaluation scenarios with data scarcity and a challenging forensic problem. Our study demonstrates the utility and potential of the self-supervised learning mechanism for image forensics applications.
    Keywords image forensics ; self-supervised learning ; machine learning ; computer-graphics image ; neural network ; image manipulation ; Technology ; T ; Engineering (General). Civil engineering (General) ; TA1-2040 ; Biology (General) ; QH301-705.5 ; Physics ; QC1-999 ; Chemistry ; QD1-999
    Subject code 006
    Language English
    Publishing date 2023-02-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: Impact of Corporate Governance on Environmental Protection Investment of China’s Listed Enterprises in High-polluting Industry

    Kai Wang

    Nature Environment and Pollution Technology, Vol 20, Iss 1, Pp 385-

    2021  Volume 390

    Abstract: With the rapid development of the economy, people’s pursuit of the quality of life is getting higher. Thus, environmental pollution will be punished, and the high-polluting industry will face more problems in development. To explore the impact of ... ...

    Abstract With the rapid development of the economy, people’s pursuit of the quality of life is getting higher. Thus, environmental pollution will be punished, and the high-polluting industry will face more problems in development. To explore the impact of corporate governance on environmental protection investment, 28 listed enterprises in high-polluting industry in China were selected as samples. Corporate governance was reflected from four aspects as explaining variables including shareholding structure, board composition, characteristics of the supervisory board and executive incentive. The relationship between corporate governance and high-polluting enterprises’ environmental protection investment was analysed by using the data of China’s listed enterprises in the high-polluting industry from 2015 to 2019. The results indicate that there is a positive correlation between legal person proportion and environmental protection investment of high-polluting enterprises, and a U-shaped relationship of the Herfindahl index. There is a significant positive correlation between board size and environmental protection investment of high-polluting enterprises, and the relationship is significantly negative of the size of the board of supervisors. The conclusions are helpful to improve the corporate governance of high-polluting enterprises, to enhancing environmental protection investment.
    Keywords listed enterprises ; high-polluting industry ; corporate governance ; panel data ; Environmental effects of industries and plants ; TD194-195 ; Science (General) ; Q1-390
    Subject code 650
    Language English
    Publishing date 2021-03-01T00:00:00Z
    Publisher Technoscience Publications
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: Urban aerial mobility

    Kai Wang / Xiaobo Qu

    The Innovation, Vol 4, Iss 2, Pp 100392- (2023)

    Reshaping the future of urban transportation

    2023  

    Keywords Science (General) ; Q1-390
    Language English
    Publishing date 2023-03-01T00:00:00Z
    Publisher Elsevier
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Article ; Online: Quantum circuit simulation of superchannels

    Kai Wang / Dong-Sheng Wang

    New Journal of Physics, Vol 25, Iss 4, p

    2023  Volume 043013

    Abstract: Quantum simulation is one of the central discipline to demonstrate the power of quantum computing. In recent years, the theoretical framework of quantum superchannels has been developed and applied widely as the extension of quantum channels. In this ... ...

    Abstract Quantum simulation is one of the central discipline to demonstrate the power of quantum computing. In recent years, the theoretical framework of quantum superchannels has been developed and applied widely as the extension of quantum channels. In this work, we study the quantum circuit simulation task of superchannels. We develop a quantum superchannel simulation algorithm based on the convex decomposition into sum of extreme superchannels. We demonstrate the algorithm by numerical simulation of qubit superchannels with high accuracy, making it applicable to current experimental platforms. Our study stands as an expansion of the superchannel theory to the field of quantum simulation and algorithm, as well as an extension of quantum simulation from channels and open-system dynamics to superchannels and processes with manifest quantum memory effects.
    Keywords quantum simulation ; quantum superchannel ; extreme points ; Science ; Q ; Physics ; QC1-999
    Language English
    Publishing date 2023-01-01T00:00:00Z
    Publisher IOP Publishing
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  5. Article ; Online: Meet our Editorial Board Member

    Kai Wang

    Journal of Applied Bioanalysis, Vol 5, Iss 1, Pp 7-

    Dr. Kai Wang

    2019  Volume 8

    Keywords Bioanalysis ; Bioanalytical Chemistry ; Pharmacy and materia medica ; RS1-441 ; Chemistry ; QD1-999
    Language English
    Publishing date 2019-01-01T00:00:00Z
    Publisher Betasciencepress Publishers
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article ; Online: Urban aerial mobility

    Kai Wang / Aoyong Li / Xiaobo Qu

    The Innovation, Vol 4, Iss 2, Pp 100393- (2023)

    Network structure, transportation benefits, and Sino-US comparison

    2023  

    Keywords Science (General) ; Q1-390
    Language English
    Publishing date 2023-03-01T00:00:00Z
    Publisher Elsevier
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  7. Article ; Online: Research on hidden fire source detection in goaf of Hengyi coal mine

    Kai Wang / Kai Dou / Sichen Zhao / Shoushi Zhang

    E3S Web of Conferences, Vol 385, p

    2023  Volume 01010

    Abstract: Coal fires cause waste of coal resources, air pollution, and threaten the safe production of coal mines, but concealed fire source detection is difficult, and a single detection method has limitations, which makes it difficult to accurately determine the ...

    Abstract Coal fires cause waste of coal resources, air pollution, and threaten the safe production of coal mines, but concealed fire source detection is difficult, and a single detection method has limitations, which makes it difficult to accurately determine the location of fire source. In order to verify the detection effect of the composite detection method on the concealed fire source, according to the isotope radon detection method and magnetic detection principle, the proton magnetometer and radon meter were used to detect the hidden fire source detection area of Hengyi Coal Mine. According to the verification of subsequent anomalous area drilling, the results show that when detecting hidden fire sources, a variety of fire source detection methods can improve the accuracy and efficiency of fire source detection. The exploration and research in Hengyi Coal Mine has laid a solid foundation for the subsequent work of extinguishing coal fires, which is conducive to the safe production of coal mines.
    Keywords Environmental sciences ; GE1-350
    Subject code 690
    Language English
    Publishing date 2023-01-01T00:00:00Z
    Publisher EDP Sciences
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article ; Online: A Study on the Evacuation of an Extra-Long Highway Tunnel Fire—A Case Study of Chengkai Tunnel

    Kai Wang / Jingwei Hu / Ruiding Chen / Jianhua Wang

    Sustainability, Vol 15, Iss 4865, p

    2023  Volume 4865

    Abstract: The smoke from tunnel fires spreads over long distances and is difficult to vent. Smoke accumulation leads to high temperatures, low visibility, and high concentrations of toxic gases, which greatly hinders the evacuation of people inside the tunnel. In ... ...

    Abstract The smoke from tunnel fires spreads over long distances and is difficult to vent. Smoke accumulation leads to high temperatures, low visibility, and high concentrations of toxic gases, which greatly hinders the evacuation of people inside the tunnel. In this paper, a representative extra-long highway tunnel—Chengkai Tunnel—is selected as the engineering background, and a tunnel model is built using FDS and Pathfinder software to simulate the fire scenario and evacuation scenario under different longitudinal wind speeds. The concept of safe evacuation reliability is proposed to describe the relationship between the ASET (available safe egress time) and the RSET (required safe egress time). The simulation results show that with the increase in longitudinal wind speed, the ASET upstream of fire source increases first and then remains unchanged, while ASET downstream of fire source increases first and then decreases. The ASET upstream of the fire source is affected by visibility, while the ASET downstream of the fire source is affected by visibility when the wind speed is low, and is affected by temperature as the wind speed increases. The bottleneck effect is an important reason for the long evacuation time of people. The blockage time is a power function of the evacuation movement time, and increasing the width of the cross passage can improve the evacuation efficiency of the tunnel. The increase in the number of evacuees will reduce the reliability of the safe evacuation of personnel. Among all simulated scenarios, a longitudinal wind speed of 2.5 m/s has the highest safe evacuation reliability, with 0.79, 0.92, and 0.99 for scenarios R1, R2, and R3, respectively. Excessive wind speed reduces the safe evacuation reliability downstream of the fire source.
    Keywords extra-long highway tunnel ; tunnel evacuation ; ASET ; RSET ; safety evacuation reliability ; Environmental effects of industries and plants ; TD194-195 ; Renewable energy sources ; TJ807-830 ; Environmental sciences ; GE1-350
    Subject code 551
    Language English
    Publishing date 2023-03-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article ; Online: Bending and Fitting

    Kai Wang

    Social Sciences, Vol 6, Iss 4, p

    Disciplinarized Institutionalization of Modern Science in China during the ‘Treaty Century’

    2017  Volume 153

    Abstract: This article investigates how Western science established itself through disciplinarized institutionalization in China as the country entered the modern era, delineating China’s science and technology (S&T) enterprises evolving within the social settings ...

    Abstract This article investigates how Western science established itself through disciplinarized institutionalization in China as the country entered the modern era, delineating China’s science and technology (S&T) enterprises evolving within the social settings primarily decided by Confucianism doctrines including Scholar-bureaucrat virtue. Although the perspective of this study is mainly historical, I also adopt a sociological approach to scientific knowledge production in order to argue that, the socialization of Western science during the ‘Treaty Century’ (1842–1943) has shaped and channeled the growth of modern S&T as well as its governance in contemporary China in a normative manner. It is this sociological interpretation of the history of modern science in China that sheds new light on our understanding of scientific knowledge as a component element of belief system that crosses countries, social structures, and civilizations. The main findings also include the premises on which the S&T governance issues are explored in China’s case, in particular, the increased social mobility at the intrusion of the Western.
    Keywords disciplinarized institutionalization ; modern science ; scholar-bureaucratic virtue ; utilitarian view ; Social Sciences ; H
    Subject code 950
    Language English
    Publishing date 2017-12-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  10. Article ; Online: Design and Application of Logical Range Framework Based on Digital Twin

    Hao Chen / Zheng Dang / Xinhong Hei / Kai Wang

    Applied Sciences, Vol 13, Iss 6589, p

    2023  Volume 6589

    Abstract: With the development of the concept of integrated flight testing, joint testing has become a key research trend. The use of a Logical Range can allow one to overcome the shortcomings of traditional test ranges, allowing for full use of the resources of ... ...

    Abstract With the development of the concept of integrated flight testing, joint testing has become a key research trend. The use of a Logical Range can allow one to overcome the shortcomings of traditional test ranges, allowing for full use of the resources of each range when implementing joint flight testing. However, the Logical Range concept also has problems, such as those relating to the low reusability of test resources and insufficient ability to monitor the resource status in real-time. Considering such problems, a Logical Range framework based on digital twin technology is proposed in this paper. On the basis of this framework, a Logical Range system based on a digital twin for the real-time mapping of real physical behavior is constructed and the three key technologies used in the system are detailed. The feasibility of the framework is successfully verified through a flight test, demonstrating that the proposed framework can provide key support for the application of digital twin technology in the field of flight testing.
    Keywords logical range ; flight test ; joint test ; digital twin ; Technology ; T ; Engineering (General). Civil engineering (General) ; TA1-2040 ; Biology (General) ; QH301-705.5 ; Physics ; QC1-999 ; Chemistry ; QD1-999
    Subject code 621
    Language English
    Publishing date 2023-05-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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