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The traditional manufacturing systems are often enterprise-centric systems, whereas the modern chemical industry is oriented towards industrial chain integration. Enterprise entities present a loosely coupled state at the scale of the industrial chain, with decentralized characteristics. This poses greater challenges and requirements for the industrial safety system. Based on the characteristics of the chemical manufacturing industry and blockchain, the application of the information security of blockchain in the chemical manufacturing industry is studied herein and the cyber-physical systems security architecture model of dual blockchains is proposed. The first-layer blockchain is applied at the system's core function level to solve security issues at the system level and provide security guarantees for communication, transactions, and billing between users and manufacturers. Meanwhile, the second layer involves the system resource layer, which not only solves the security problem of cross-level platform data interaction, but also enables the point-to-point security of the device-level cyber-physical system to ensure internal equipment communication information security. A domestic commercial concrete manufacturing company's real production and operation data were used to simulate basic functions such as transaction requests, trade success, and blockchain queries. After multiple tests, results show that its basic blockchain, query response, transaction creation, and block creation functions are all finished within milliseconds, meeting the industrial requirements. Its safety verification can meet the requirements of safety, efficiency, and low latency for production control in chemical industry sites, proving the feasibility of applying the dual blockchain model in the chemical manufacturing industry. Based on data security, privacy, and integrity requirements, the blockchain technology proposed in this article provides a more efficient, transparent, and secure operation and management solution for the chemical industry. [ABSTRACT FROM AUTHOR]

This paper proposes an adaptive sliding mode control based on an auxiliary distance sensor for nonlinear platoons over vehicular ad‐hoc networks under Denial‐of‐Services (DoS) attacks and external disturbances. DoS attacks can cause packet dropping for the wireless network and will lead to the collision or degradation to adaptive cruise control of platoons. To solve this problem, an adaptive Radial Basis Function (RBF) sliding mode control method is proposed for the attacked platoons. RBF neural networks are used to approximate the unknown nonlinear part and external disturbances contained in the vehicle models. Then the adaptive sliding mode controllers are designed to achieve the control goals: the spacing error converges to zero, and the platoon maintains the string stability. The system's internal stability and string stability are proved. Numerical examples are applied to show the effectiveness of the proposed method. Compared with the existing method, the spacing error is decreased from 5.0726, 6.4637 to 0.0264 for secure distributed adaptive platooning control in PF topology and LPF topology, and the average distance is increased from 7.0580 m, 5.7442 m to 11.8498 m for secure distributed adaptive platooning control in PF topology and LPF topology to maintain a safe distance under the situation of DoS attacks. [ABSTRACT FROM AUTHOR]

In this paper, we study the extreme values of the Rankin–Selberg L -functions associated with holomorphic cusp forms in the vertical direction. Assuming the generalised Riemann hypothesis (GRH), we prove that $$ \begin{align*} \underset{T^{\delta}\leq t\leq T}{\max}\bigg\lvert L\bigg(\frac12+it,f\times f\bigg)\bigg\rvert \geq\exp\bigg(C\sqrt{\frac{\log T\log\log\log T}{\log\log T}}\bigg) \end{align*} $$ with $C\leq \mathscr {X}\sqrt {1-\delta }$ , where $\mathscr {X}:=({2}/{\pi })\int _{0}^{\pi /3}\sin ^2\xi \,d\xi $ and $0\leq \delta. [ABSTRACT FROM AUTHOR]

This article, published in the European Heart Journal, discusses a case study of an 82-year-old patient who was found to have both a giant abdominal aortic aneurysm and a thoracic aortic dissecting aneurysm. Due to the patient's age and medical history, open surgery was deemed high-risk, and a one-stage operation was chosen to isolate both aneurysms. The authors used three-dimensional printing to guide the creation of fenestrations in sixth fenestrated physician-modified stent grafts. The patient had a successful operation and was discharged from the hospital without complications. [Extracted from the article]

At the different radioactivity, temperature, pressure, heights, and incident angles, the influences of the electromagnetic wave propagating in the \alpha -decay radionuclide layer (RNL) coated on a perfect electric conductor system were simulated by the finite-difference time-domain method. The maximum electron density ionized by 5.45-MeV \alpha -particles is \sim 1.8\times 10^11 per cubic centimeter when the radioactivity is 10 Ci/ \mathrmcm^2 . The decrease of the reflectivity at altitude is much better than at ground and the decreasing amplitudes could reach 1–20 dB in the frequency range from 300 MHz to 40 GHz at an altitude of 10 000 m. In addition, the same RNL would significantly reduce the back scattering bistatic radar cross section (RCS) of the platform. The decrease of RCS along the direction of the originally strongest reflection wave is nearly 25.5 dB when the incident angle is 60°. [ABSTRACT FROM PUBLISHER]

We present a novel active imaging approach that uses optimized wide band filtered illumination to obtain multi-spectral reflectance information. Our optimization algorithm utilizes light source and camera spectral information in order to maximize the signal strength and the robustness to noise. Through the use of active wide band illumination, our system can obtain material reflectance information in the presence of moderate (indoor) unknown ambient illumination. Our method is very simple and does not require special equipment. It can be used by photographers to obtain material properties in uncontrolled environment and to synthesize captured scenes under arbitrary illumination. [ABSTRACT FROM AUTHOR]