9 research outputs found

    Extreme Limit Theory of Competing Risks under Power Normalization

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    Advanced science and technology provide a wealth of big data from different sources for extreme value analysis.Classic extreme value theory was extended to obtain an accelerated max-stable distribution family for modelling competing risk-based extreme data in Cao and Zhang (2021). In this paper, we establish probability models for power normalized maxima and minima from competing risks. The limit distributions consist of an extensional new accelerated max-stable and min-stable distribution family (termed as the accelerated p-max/p-min stable distribution), and its left-truncated version. The limit types of distributions are determined principally by the sample generating process and the interplay among the competing risks, which are illustrated by common examples. Further, the statistical inference concerning the maximum likelihood estimation and model diagnosis of this model was investigated. Numerical studies show first the efficient approximation of all limit scenarios as well as its comparable convergence rate in contrast with those under linear normalization, and then present the maximum likelihood estimation and diagnosis of accelerated p-max/p-min stable models for simulated data sets. Finally, two real datasets concerning annual maximum of ground level ozone and survival times of Stanford heart plant demonstrate the performance of our accelerated p-max and accelerated p-min stable models

    Extreme analysis of typhoons disaster in mainland China with insurance management

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    Due to climate change, typhoons, especially extreme typhoons, are becoming more intense and causing ascending financial losses. A majority of previous studies on typhoon economic losses over a period of time considered all types of typhoon rather than the extreme typhoons. This study focuses on the risk management of extreme typhoons by establishing the compensation mechanism and a typhoon-specific insurance product. The annual maximum losses of typhoons is first modelled by generalized extreme value distribution (GEV) under the Extreme Value Theory (EVT). The prediction of unexpected economic losses is then obtained via VaR and CVaR for the compensation mechanism among individual, insurance company and government. To analyse the typhoon vulnerability of 11 Chinese coastal provinces (or municipalities), the Multiple-Criteria Decision Making (MCDM) method, combining Analytic Hierarchy Process (AHP) based Grey Rational Analysis (GRA) and Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS), is applied for evaluating the typhoon vulnerability of these regions for 2022. The nationwide best estimates for typhoon reserves on the basis of insurance compensation mechanism is therefore calculated and will be allocated to these 11 provinces according to the vulnerability ranking obtained via MCDM method. The findings indicate that the top three provinces (Guangdong, Fujian and Zhejiang) in typhoon vulnerability rankings are also with the highest losses and frequency in practice, while Hebei has the highest insurance premium

    Wide-Range Linear Iontronic Pressure Sensor with Two-Scale Random Microstructured Film for Underwater Detection

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    A broad linear range of ionic flexible sensors (IFSs) with high sensitivity is vital to guarantee accurate pressure acquisition and simplify back-end circuits. However, the issue that sensitivity gradually decreases as the applied pressure increases hinders the linearity over the whole working range and limits its wide-ranging application. Herein, we design a two-scale random microstructure ionic gel film with rich porosity and a rough surface. It increases the buffer space during compression, enabling the stress deformation to be more uniform, which makes sure that the sensitivity maintains steady as the pressure loading. In addition, we develop electrodes with multilayer graphene produced by a roll-to-roll process, utilizing its large interlayer spacing and ion-accessible surface area. It benefits the migration and diffusion of ions inside the electrolyte, which increases the unit area capacitance and sensitivity, respectively. The IFS shows ultra-high linearity and a linear range (correlation coefficient ∼ 0.9931) over 0–1 MPa, an excellent sensitivity (∼12.8 kPa–1), a fast response and relaxation time (∼20 and ∼30 ms, respectively), a low detection limit (∼2.5 Pa), and outstanding mechanical stability. This work offers an available path to achieve wide-range linear response, which has potential applications for attaching to soft robots, followed with sensing slight disturbances induced by ships or submersibles

    Wide-Range Linear Iontronic Pressure Sensor with Two-Scale Random Microstructured Film for Underwater Detection

    No full text
    A broad linear range of ionic flexible sensors (IFSs) with high sensitivity is vital to guarantee accurate pressure acquisition and simplify back-end circuits. However, the issue that sensitivity gradually decreases as the applied pressure increases hinders the linearity over the whole working range and limits its wide-ranging application. Herein, we design a two-scale random microstructure ionic gel film with rich porosity and a rough surface. It increases the buffer space during compression, enabling the stress deformation to be more uniform, which makes sure that the sensitivity maintains steady as the pressure loading. In addition, we develop electrodes with multilayer graphene produced by a roll-to-roll process, utilizing its large interlayer spacing and ion-accessible surface area. It benefits the migration and diffusion of ions inside the electrolyte, which increases the unit area capacitance and sensitivity, respectively. The IFS shows ultra-high linearity and a linear range (correlation coefficient ∼ 0.9931) over 0–1 MPa, an excellent sensitivity (∼12.8 kPa–1), a fast response and relaxation time (∼20 and ∼30 ms, respectively), a low detection limit (∼2.5 Pa), and outstanding mechanical stability. This work offers an available path to achieve wide-range linear response, which has potential applications for attaching to soft robots, followed with sensing slight disturbances induced by ships or submersibles

    Wide-Range Linear Iontronic Pressure Sensor with Two-Scale Random Microstructured Film for Underwater Detection

    No full text
    A broad linear range of ionic flexible sensors (IFSs) with high sensitivity is vital to guarantee accurate pressure acquisition and simplify back-end circuits. However, the issue that sensitivity gradually decreases as the applied pressure increases hinders the linearity over the whole working range and limits its wide-ranging application. Herein, we design a two-scale random microstructure ionic gel film with rich porosity and a rough surface. It increases the buffer space during compression, enabling the stress deformation to be more uniform, which makes sure that the sensitivity maintains steady as the pressure loading. In addition, we develop electrodes with multilayer graphene produced by a roll-to-roll process, utilizing its large interlayer spacing and ion-accessible surface area. It benefits the migration and diffusion of ions inside the electrolyte, which increases the unit area capacitance and sensitivity, respectively. The IFS shows ultra-high linearity and a linear range (correlation coefficient ∼ 0.9931) over 0–1 MPa, an excellent sensitivity (∼12.8 kPa–1), a fast response and relaxation time (∼20 and ∼30 ms, respectively), a low detection limit (∼2.5 Pa), and outstanding mechanical stability. This work offers an available path to achieve wide-range linear response, which has potential applications for attaching to soft robots, followed with sensing slight disturbances induced by ships or submersibles
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