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With the continuous development of information and communication technologies (ICT) as well as their applications in the industrial environment, industrial internet comes into being. In comparison to the relatively closed and secure production environment of traditional industries, the industrial internet faces significant security challenges in terms of data privacy. This paper investigates the privacy-preserving control problem for data opacity of the industrial internet to provide a resilient defending strategy against cyber threats, where the system to be controlled is modeled as a networked discrete-event system (DES) and malicious eavesdroppers exist to infer the system secret based on its observations. We here aim at designing a networked supervisor to achieve the following two objectives: (1) eavesdroppers cannot infer the system secret based on its observations, which is formulated as the requirement of opacity enforcement, (2) under the control of the designed networked supervisor, the system could still achieve the predetermined control requirement. To solve the previously mentioned privacy-preserving supervisory control problem, this paper first proposes a privacy-preserving control architecture for networked DES, in which each component is modeled as a finite-state automaton to simulate its dynamics. We design an algorithm based on the constructed models to synthesize the networked supervisor by transforming the original privacy-preserving control problem into a classical Ramadge-Wonham supervisory control problem. Furthermore, this paper proves (1) the designed synthesis algorithm is sound and complete, and (2) the existence of the supremal networked supervisor for this privacy-preserving supervisory control problem. 国家重点研发计划 (编号: 2018YFB1701202) 和国家自然科学基金青年基金 (批准号: 51905197) 资助项目.

Information sharing solves the problem of information asymmetry between banks to a certain extent, but it also brings about the leakage of customer privacy. Therefore, how to protect data privacy while sharing data is an urgent issue. Blockchain protects the privacy of accounts and data while sharing data. Therefore, we propose a blockchain-based loan over-prevention mechanism. The program can hide the customer loan/repayment amount and thus protect the customer's privacy; we prove that the customer's loan amount is within a certain range and does not exceed the remaining loanable amount via a range proof. In order to share customer loan information between banks, we store the commitment of customers' amounts in the blockchain, and banks can obtain relevant information directly from the chain, which also reduces the amount of communication between banks. Finally, we implement the model and performe a performance analysis.

A sub-picomole level topotecan hydrochloride determination method was first proposed using sodium dodecyl sulfate (SDS) as a sensitized reagent at a novel disposable electrode (an improved wax-impregnated graphite electrode). The effects of different kinds of surfactants on the electrochemical response to topotecan hydrochloride were examined. The results indicate the electrochemical signal was apparently improved by SDS. At optimal conditions, the oxidative peak current increased linearly with the logarithm of concentrations for topotecan hydrochloride in the ranges of 2.0 × 10−12 to 1.0 × 10−11 mol/L and 8.0 × 10−11 to 8.0 × 10−10 mol/L with a detection limit of 6.4 × 10−13 mol/L. The proposed method could be applied in determining topotecan hydrochloride in urine.

In a new two-phase system (tetrahydrofuran/saturated NaCl aqueous solution) monolayer protected clusters (MPCs) were prepared. The AuCl4− anion in saturated electrolyte aqueous solution was transferred into the organic phase of tetrahydrofuran by tetra-n-butylammonium bromide ((C4H9)4NBr) and was reduced quickly by sodium borohydride in the presence of alkanethiol. The functionalized MPCs were characterized by solubility, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray (EDX) analysis and UV-vis spectroscopy. Electrochemical measurements of MPCs in CH2 Cl2 exhibited 7 pairs of reversible voltammetric waves within the potential range of −1.0 to 1.0V (vs Ag/AgCl), which was ascribed to the quantized capacitance charging of nanoparticle double layers. All the results show that the new preparing method is feasible.

The azocalix[4]arene film modified glassy carbon electrode was established for the convenient and sensitive detection of four DNA bases (guanine, adenine, thymine and cytosine). Field emission scanning electron microscopy, attenuated total reflectance-FTIR and X-ray photoelectron spectroscopy were used to characterize the film. The azocalix[4]arene film exhibited excellent electrocatalytic activity toward the oxidation of all bases. Well-separated voltammetric peaks were obtained among guanine, adenine, thymine and cytosine, which lead to the feasibility for the simultaneous determination of all of them in a mixture without separation or pretreatment. Linear calibration curves were obtained from 0.125 to 200.0 μM for adenine, 0.125 to 175.0 μM for guanine, 2.50 to 650.0 μM for thymine, and 2.50 to 650.0 μM for cytosine. This sensor also exhibits good stability, reproducibility and long lifetime.

Wireless underground sensor networks (WUSNs) consist of wireless devices buried below the ground surface and aboveground sink devices, in which the communication medium is not only air but also soil. In this paper, improved channel models based on time-domain are developed to characterize underground-underground, underground-aboveground and aboveground-underground electromagnetic waves channels, which capture the effects of environment parameters such as soil composition and soil moisture, and system parameters such as the antenna gain, operating frequency, the sensor burial depth. The propagation characteristics are investigated through simulation results of path loss between two nodes. This work will accelerate the design and realization of WUSNs.