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A lattice-based group signature scheme (LGSS) is an active cryptographic primitive, where each group member can sign messages anonymously in the name of the entire group and each valid signature should be traced to some group member on the lattice. In each LGSS, the size of the group signature usually depends on the number of group members and the security parameter. Thus, designing a constant-size LGSS is an interesting problem. At PKC 2018, Ling, Nguyen, Wang and Xu presented the first constant-size group signature scheme under lattice assumptions. Its design is based on a zero-knowledge argument of the knowledge of a valid message-signature pair for the Ducas-Micciancio signature scheme, which follows the sign-then-encrypt-then-prove protocol. In contrast to this work, we construct a new constant-size LGSS. The scheme adopts the sign-hybrid-encrypt approach and makes use of the Lyubashevsky signature scheme. Our work is efficient in the signing algorithm, more precise on the open algorithm and shorter in public key, secret key and signature size than previous studies. Furthermore, we prove that the scheme has full anonymity and full traceability under the Ring Learning With Errors and Ring Short Integer Solution assumptions in the random oracle model.

Takes a field measurement in traffic statistics, indoor and outdoor temperature and humidity, analyzes the thermal environment of the railway station waiting room of Xi’an. Investigates the thermal comfort status using ASHRAE seven sensation scales by questionnaires, survey the people’s satisfaction to the environment of waiting room.

In this study, Biosorption of Ni (II) ions from aqueous solution by using biomass ofAspergillusnigerwas investigated. Different parameters such as initial pH, Ni (II) ions concentration, contact time and temperature were explored. The biosorption of Ni (II) ions was highly pH dependent and the optimum pH for biosorption of Ni (II) ions was found to be 7.0. The biosorption equilibrium was established in about 30min of contact time. Ni (II) ions removal increased with increasing temperature in the studied range. Equilibrium uptake of Ni (II) ions onto biomass increased with increasing initial Ni (II) ions concentration (20-300mg/L). The Langmuir and Freundlich isotherm models were applied to experimental equilibrium data and the Langmuir model better described the equilibrium metal uptake than the Freundlich model. These results suggest that the biomass ofAspergillusnigeris a promising biosorbent for removal of nickel (II) ions from the wastewater.

In this study, Biosorption of Cr (VI) ions from aqueous solution by using biomass of Aspergillus niger was investigated. The effects of initial solution pH, biosorbent amount, contact time, initial concentration and temperature were explored. In batch experiments, the biosorption capacity of Cr (VI) decreased with increase in solution pH. The biosorption of Cr (VI) ions with pH range of 2.0-8.0 was found to be optimal at pH 2. Biosorption capacity of Cr (VI) ions decreased with increased biosorbent dosage. The bosorption capacity was increased with the increasing initial Cr (VI) concentration and temperature in studied range. The biosorption process followed the pseudo-second order kinetic model and the correlation coefficients from the pseudo-second order model were all higher than 0.9997 in all studied temperatures. These results suggest that the biomass of Aspergillus niger is a promising biosorbent for removal of Cr (VI) ions from the wastewater.

By describing the environmental requirements for food storage, puts forward the green air conditioning system to create a low-temperature environment for food of these creatures such as ice storage air-conditioning, ground source heat pumps, solar cooling and so on. Combined the related system diagram or schematic in the context of promoting green and healthy, pointed out the future direction of development of the low-temperature grain storage.

Energy storage capacitance is necessary part of pulse power generator. Generally, it is difficult to match the equivalent capacitance in high voltage side and energy storage capacitance in low voltage side of the pulse transformer. Resultantly, it requires high flow capability of switch device. In this paper, three methods are presented to solve this problem based on reasons of overcurrent. The results of simulation and experiments show that the efficiency of generator was higher with the method of thyristor and inductance in reverse parallel, and this method would be the most effective resolution.

In this paper, a compact TLT is developed basted on the theories of transmission line and a LCR triggered switch is introduced. A compact structure of components and topology is designed to reduce the influence of the total inductance of capacitor discharge circuit. The experimental results indicate that the voltage gain is up to 1.98. A pulse with peak voltage of up to 20kV, duration time of 200ns and rise time of about 25ns is obtained; the TLT could work successfully in 500Hz.