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In this paper, we examine a bivariate insurance risk model that incorporates two distinct business lines. The model encompasses both independent aggregate claims and common shocks to represent the interdependence between losses in these two lines of business. The monitoring of the bivariate risk model occurs periodically, with constant inter-observation intervals. During each observation, dividends may be distributed using a barrier strategy in both business lines. To evaluate the expected present value of operating costs until ruin, we employ the two-dimensional Fourier-cosine series expansion as an approximation technique. The paper derives explicit approximation formulas and conducts an analysis of the approximation errors. In addition, numerous numerical results are presented to demonstrate the effectiveness of our method, and we examine the impacts of various parameters in the model. At the same time, we also study the problem of capital allocation and the optimal dividend barrier problem for bivariate processes.

In view of the impact of climate change on human development, countries have taken measures to reduce carbon emissions and carbon sequestration. Forest carbon sink plays a pivotal part in achieving carbon neutrality in China. China has put forward the 'double carbon' goal of carbon peak and carbon neutralisation. Firstly, using the data of nine forest resources inventory from 1973 to 2018, an evaluation model of forest carbon sequestration effect in China is established, and 24 provinces in China are compared and analysed. Secondly, the grey correlation analysis model is used to study the dynamic change of forest carbon sink effect and forest resources in China. Finally, it provides reasonable advice for the development and management of forest resources in China, improves the level of forest management, and provides a basis for the implementation of China's carbon peak and carbon neutral strategy.

The regulatory mechanisms of the processes of RNA accumulation were examined from a chemical perspective in repeat-expansion disorders, which induce cytotoxicity and cause neurodegenerative diseases. We found that the accumulation, including production, gelation, and sedimentation, of RNA repeats transcribed from repeat expansions related to neurodegenerative diseases was greatly accelerated by G-quadruplex-forming RNA repeats, although no acceleration was induced by hairpin-forming RNA repeats. We also investigated the relationship between accumulation and physical solution properties, such as viscosity and water activity, and found that RNA accumulation was promoted through a decrease in the dielectric constant. Importantly, we found that the RNA accumulation required RNA G-quadruplexes and was promoted by changes in the dielectric property of the cell induced by an ion channel inhibitor. Our study is the first to show that the accumulation processes that induce toxicity in cells can be controlled via electrostatic interactions in the RNA G-quadruplex; thus, these can form the basis of guidelines for the chemical control of cell toxins.

To understand the mechanism for formation of non-canonical nucleic acid structures, especially G-quadruplexes, is important for gene expression because the G-quadruplexes inhibit efficiently biological reactions. In this study, we utilized a fluorescent G-quadruplex ligand to quantitatively monitor G-quadruplex formation and dissociation in six different G-rich templates during transcription. Interestingly, increased and decreased G-quadruplex formation were observed depending on the sequence contexts. The formation of G-quadruplex was related to stabilization of the G-quadruplex after unwinding of the templates by the surrounding environment, while dissociation of the G-quadruplex was related to the potential triplet structures formed between C-rich sequences in the non-template strand and G-rich sequences in the template strand. The interaction between the template and non-template strand plays an important role in regulating G-quadruplex formation and dissociation in the template strand, which affects gene expression.The folding and dissociation of G-quadruplexes in template strands during transcription were quantitatively investigated. In certain sequence contexts, C-rich non-template strands played important roles in regulating G-quadruplex folding before and after transcription potentially through triplet formation and further influenced gene expression.

Based on the established full-car active suspension model, fuzzy control theory was combined with neural network control, the fuzzy neural network control system of vehicle active suspension was designed, simulation and analysis of random road input and sine wave input were carried on. The results show that, by comparison with the traditional suspension system, the peak and standard deviation of vehicle mass vertical acceleration decreased by 55.38% and 59.04%, the peak of vehicle mass vertical acceleration decreased by 49.96% when vehicle go through the sine wave at the speed of 5m/s, the ride comfort was improved obviously.

A laser ablated plasma created by an ArF excimer laser of wavelength of 193 nm, laser power of 150-200 mJ, repetition rate of 1 Hz, and zinc, copper, iron and nickel targets was studied. Quantitative emission studies are reported that are both space and time resolved. The space results of the laser ablated plasma suggest a confined plasma with a gaussian type distribution of atoms and ions. The time resolved studies show a maximum emission signal occurring at approximately 20 s with a lifetime of less than 100 s.

Quantitative plasma power emission measurements of the effect of increasing laser energy for the interaction of a 193-nm wavelength laser on four selected metals are presented. A correlation between a theoretical model for mass vaporized and increasing laser energy intensity was found for the selected metals.

A novel device for low-power fault-tolerant laser-to-fiber coupling is described; it makes use of self-pumped phase conjugation in photorefractive BaTiO_3. We found the degree of fault tolerance to improve by 2 orders of magnitude to 0.02 dB per 100-μm displacement within the determined displacement range at intensities incident on the crystal as low as 2 mW, compared with the losses without the BaTiO_3 present.

The effects of pressure over the range 10 to 760 Torr and of atmosphere (air, argon, and helium) on an ArF-excimer laser (λ= 193 nm) ablated plasma created above the surface of a copper target was studied with the use of emission measurements. These factors greatly influenced the shape, line-to-background (L/B) ratio, and temperature of the plasma. In general, the size of the plasma decreased with increasing pressure. In air or argon, and at pressures less than 50 Torr, the plasma consisted of two distinct regions. With the use of neutral copper [Cu(I)] lines, reduced pressure from 760 to 10 Torr resulted in a 7-fold increase in air and an 11-fold increase in an argon atmosphere. With the use of a helium atmosphere, the maximum line intensity was obtained at 50 Torr. This was a 1.5-fold increase over that obtained at 760 Torr. With a reduction in the pressure in air or argon, the position of maximum intensity (for copper atom and ion lines) moved away from the surface. For helium, the position of maximum intensity did not significantly vary in accordance with a reduction in the pressure. In general, the plasma temperature decreased with decreasing pressure.

Spatial measurements of the emission spectra of a laser-generated plasma were obtained for copper and lead targets. Results showed that the two metals gave quite different sizes of plasma, the plasma formed with copper extending 2 mm, and that with lead extending 5 mm, above the metal surface. Excitation temperatures of the plasma ranged from 13,200 to 17,200 K for copper and 11,700 to 15,300 K for lead.

Determination of the excitation temperature of a laser ablated plasma created when an excimer beam of wavelength 193 nm, pulse energy of 200 mJ and repetition rate of 1 Hz is focussed on a copper target was found to be 15,924 K. Atom to ion emission ratios with increasing laser energy showed an increase in ion emission (compared to atom) at a laser energy of 120 mJ. Theoretical simulation of mass ablated with selected properties (specific heat, thermal conductivity, and density) of copper, zinc, iron, and nickel were studied.