We considered a class of stochastic premium risk model with investment income, and assumed that the interest rate process was a non-negative Lévy process. We obtained nonexponential upper bounds of the ruin probability by martingale and inductive approaches, respectively, and gave some numerical simulations to illustrate the advantage of the nonexponential upper bounds.

The numerical solution of wave front did not propagate forward when one tried to solve the onedimensional degenerate nonlinear parabolic (DNP) problem with the standard mixed finite element method. By analyzing the defect of the standard mixed finite element method for solving the degenerate equations, we proposed a nonstandard mixed finite element method. The definition of intermediate variable in the method did not include diffusion coefficient, but only the derivative of primal unknown function with respect to spatial variable. Based on typical model problems, the effectiveness of the proposed method was verified by the numerical experiments.

By using the fixed point theorem of cone expansion and compression, we studied the secondorder singular boundary value problem with general differential operator, in which the coefficients of linear differential operator were also allowed to be singular. We obtained the existence result of at least one positive solution under the nonlinearity satisfying either superlinear or sublinear conditions, and gave an example to test the validity of the result.

We considered a class of stochastic SIR epidemic models with saturated incidence. By using Markov semigroup theory, we proved that the system had a unique stable stationary distribution when Rs₀^>1.

The author considered a class of struggle of existence in multigroup of nonlinear singular perturbation systems. Under appropriate conditions, the author constructed the external solution of the system, boundary layer correction terms and initial layer correction terms, and obtained the asymptotic expansion of the solution. The author discussed the existence of solution of the problem and the uniform validity of its asymptotic expansion.

We considered a blowup profile of solutions for a class of parabolic equations with nonlocal boundary conditions. On the basis of some integral inequalities, we suitably weakened the assumptions about the initial values, and obtained the global blowup properties and the blowup rate estimates of positive solutions.

We considered the structures of Lie color triple systems, and introduced the definition of generalized derivations of Lie color triple systems. Using the relations between Lie color triple systems and Lie color algebras, we obtained the related results of generalized derivations of Lie color triple systems.

By giving the notion of a strong biderivation of a Leibniz algebra, we proved that a strong biderivation can give a derivation extension of Leibniz algebras, and gave a new method for constructing Leibniz algebras.

The author gave a sufficient condition for a surjective Jordan homomorphisms to be a homomorphisms or an antihomomorphisms in the nest algebra, and proved that every surjective Jordan homomorphism between finite dimensional nest algebras must be a homomorphism or an antihomomorphism.

By gaving mutual determination relationship between quadratic matrix and quadratic polynomial, we obtained invariance of rank for generalized Jordan products of quadratic matrix and a new rank equations associated with quadratic matrix by means of matrix transformation. The results summarized and generalized the relevant results of the rank equations such as the (scalar) idempotent matrix, (scalar) involutory matrix, etc.

We gave a uniaxial optimal perfectly matched layer (PML) method for solving the scattering problem of time harmonic elastic wave based on the complex coordinate stretching in the frequency domain. By introducing a small parameter ε₀ in the absorption function, the optimal PML method for scattering problem was no longer dependent on the thickness of the PML layer. The results show that the optimal PML solution converges exponentially to the solution of the original elastic wave scattering problem if the parameter ε_0 is small sufficiently.

According to the definitions and properties of the weighted Lebesgue spaces and Herz spaces with variable exponent, using the property of variable index, and by the estimates of the Hlder inequalities, we proved the boundedness of the multilinear CalderónZygmund operators on the product of weighted Lebesgue spaces with variable exponent, and then proved the operators were bounded on the product of weighted Herz spaces with variable exponent.

We estimated the upper bound of the first eigenvalue of the Schrdinger operator L=-Δ-k(2-1/p)(S-nH²) on the ndimensional closed kextremal (k≥1) submanifold Mⁿ in a unit sphere  S^n+p(n≥3) by choosing suitable text function. Then, we gave some characteristics of submanifolds M^n based on the eigenvalue, where H and S were the mean curvature and the squared length of the second fundamental form, of Mⁿ respectively, Δ was the Laplace operator on Mⁿ.

By designing a new approximation of Hessian matrix, we obtained a new quadratic approximate model of function in the current iteration point, and used this model and delay strategy to obtain a new stepsize. Combined with the new stepsize, we proposed a modified iteratively approximated gradient projection algorithm for solving the problem of sparse signal reconstruction in compressed sensing, and gave the proof of convergence. Experimental result shows that the proposed algorithm can not only restore the nonzero elements in the original signal, but also reconstruct the signal effectively. Compared with the classical algorithm, the proposed algorithm has higher reconstruction efficiency.

With the design technique of robust controller and the design idea of robust quadratic stabilization controller, robust control of the closedloop system was
carried out to eliminate the adverse effects of delay factors and uncertainties on the actual system. By constructing a new Lyapunov functional, the author proposed design method of delaydependent and delayindependent controller based on linear matrix inequality. The results show that the designed state feedback controller can make the closedloop system satisfy the performance requirements within the allowable range of uncertainty, and reduce the sensitivity of the system. Numerical results show that the obtained results are more universal and can be applied to the nonstandard systems with uncertain timevarying delay.

By using the Markov inequality and Kolmogorov exponential inequality, we obtained the law of the iterated logarithm for extended negatively depenent (ND) identically distributed sequence for sublinear expectation space under a general moment condition. Thus, the law of the iterated logarithm under sub linear expectation space was generalized.

Let {X_n, n≥1} be an asymptotically linear  negative quadrant dependent (ALNQD) sequence with the same distribution, and f_n(x) be the kernel estimator of the density function f(x) based on the sample X₁,…,X_n. Under some suitable assumptions, the author proved the strong consistency, the uniform strong consistency and the rorder consistency of the kernel density estimator by using the moment inequalities of ALNQD sequences and BorelCantelli lemma.

Using the system of idempotents in a Banach algebra, we considered the generalized Drazin inverse of the sum of two elements. For two elements a,b
 in a Banach algebra, we gave the expressions for the generalized Drazin inverse of the sum a+b under the condition that b²a=a^πbabb^π, a²b=a^πabab^π.

We supposed that a subgroup D of a Sylow p-subgroup P of a group G satisfied 1<D≤P, where p was a prime divisor of |G|. The new sufficient conditions for the characterization of p-nilpotent groups and p-supersolvable groups were obtained by using Msupplemented property of each order of |D| subgroup in the normalizer N_G(P) of P and combining the weakly ssupplemented property of H (P)={H
≤P|P′≤H≤Φ(P)}.

Based on the structure of the quasidihedral 2-group and the properties of its elements in group theory, we used the basic method in algebra to construct all homomorphisms from two different the quasidihedral 2-groups. We also got the result that conjecture of Asai and Yoshida was satisfied on the quasi-dihedral 2-group.

We considered a class of delayed SIQR epidemic models with saturated incidence rate. Using the eigenvalue method, and the time delay caused by the cure cycle as the bifurcation parameter, we discussed the local asymptotic stability of the viral equilibrium, gave sufficient conditions for the  local asymptotic stability of the viral equilibrium, and determined the delay critical point for the occurrence of a local  Hopf bifurcation of the model. Simulation results verified the correctness of the obtained results.

Using the elements of a nonnegative rectangular tensor A, classification discussion idea and some techniques of inequalities, the author gave an upper bound estimation of the largest singular value of A. The obtained results were verified by numerical examples. Numerical results show that the obtained estimation is more accurate than some existing results.

We applied artificial immune system algorithm to the real-time detection of botnet, and proposed an online detection model based on deterministic dendritic cell algorithm. Combining the characteristics of botnets, the behavior signals were defined, and the real\|time detection of the host of botnet based on the heuristic information was realized. The validity of the model was experimentally verified by using standard data sets. Experimental results show that  this model has the advantages of real-time, simple behavior definition and accepting the definition of multiple kinds of heuristic information. Moreover, the false negative rate and false positive rate of detection of botnet are low.

In order to further improve the revenue of cloud service providers, the author proposed a revenue optimization algorithm based on alliance perception in hybrid cloud environment under the condition of reducing the cost of cloud service provider resources. The algorithm built a cloud service provider alliance, and considered  two types of virtual machine request: spot virtual machine and ondemand virtual machine. The cloud service providers at the peak load could still get the maximum revenue by outsourcing requests to other members of the alliance or the way of terminating spot virtual machine.

We proposed a seismic data compression algorithm based on waveletbased Contourlet transform (WBCT) with embedded block with coding optimized (EBCOT). Firstly, the WBCT was used to obtain the sparse representation for seismic data, and the WBCT direction decomposition was optimized according to the rule of code block entropy minimization, which reduced the complexity of the code blocks and improved the coding efficiency. Secondly, in view of the bandpass features of different geological information in wavelet domain, we improved the method of mask treatment of the region of interest (ROI) of JPEG2000 algorithm, set different weights to the different wavelet subbands for mask treatment.  Finally, the compressed bit stream was generated by EBCOT encoding. The experimental results show that the reconstructions of seismic data not only improve the PSNR, but also significantly reduce the distortions of local texture of seismic data with the same axis.

In order to hide watermark information in the original image better and accelerate detection of the watermark information, the author designed a digital image watermarking algorithm based on compressive sensing and discrete cosine transform (DCT). Firstly, original carrier image was divided into several sub blocks, and discrete cosine transform was used to decompose each sub block. Secondly, compressed sensing was used to process watermark information
 to reduce the amount of embedded information. Finally, the watermark information was embedded into the corresponding position of the original carrier sub block, and the watermark detection was realized by matching pursuit algorithm. The performance of digital image watermarking algorithm was evaluated from two aspects of subjective and objective. The results show that the watermark of this algorithm has good perception, and has good robustness against common attacks. It solves contradiction between watermark transparency and robustness, and accelerates the speed of watermark extraction.

Aiming at the defects of single feature that could only describe the partial information of image content. In order to obtain more accurate image retrieval results, we designed an image retrieval algorithm based on multifeature combination and user feedback. Firstly, many features of the image were extracted and combined to form a feature vector for image retrieval, the Euclidean distance was used to calculate the similarity between images, and the
 initial image retrieval was realized. Secondly, through the  evaluation and feedback of the initial image retrieval results, the machine learning algorithm was used to adjust the initial image retrieval results according to the feedback results, so as to achieve accurate image retrieval. Finally, the standard data of image library retrieval were simulated and tested. The test results show that the proposed algorithm achieves stable image retrieval results, and the accuracy of image retrieval is obviously higher than other algorithms.

Through the improvement of ant colony algorithm and particle swarm algorithm, using the combination of advantages of the two algorithms, the author established an ant colony particle swarm optimization algorithm to improve the efficiency of cloud computing resource scheduling and solve the resource scheduling problem in cloud computing. The experimental results show that the algorithm consumes less time and gets better results.

Aiming at the problems of computation efficiency, communication cost and security in the current certificateless multisignature scheme, we proposed a certificateless multisignature scheme based on bilinear pairings, simulated three different types of attackers, and analyzed the non forgery of the new signature algorithm. The method was based on the idea of certificateless short signature, and constructed a parallel multisignature scheme with short signature length. Simulation results show that, compared with the existing schemes, the new scheme reduces the communication cost and the amount of computation of the signature, so it is more suitable for resource constrained network environment.

In order to effectively recognize the information of text by using Android intelligent terminals, we proposed a text feature extraction method based on spectral residual (SR) and stroke width transform (SWT). Firstly, the salient map was obtained based on salient detection of the spectral residual. Secondly, the maximum entropy discriminant method was used to segment and establish salient text candidate regions in salient map. Finally, the SWT algorithm was used to extract characteristics of equivalent width of closed edge in the candidate region. The C/S architecture experimental platform was constructed based on Android intelligent terminal and server, and experimental results on both the MSRA-TD500 text dataset and laboratory dataset show that the algorithm can effectively obtain salient text feature in the image, and the performance of the algorithm is improved when the computing efficiency is guaranteed.

In order to improve the identification effect of network communication load state, we proposed a identification model of network communication load state based on relevance vector machine. Firstly, the parameters which affected the quality of network communication were extracted, and the relationship between them and their load states was analyzed. Secondly, the throughput of wireless sensor network was regarded as the standard of load state identification, and the relevance vector machine was used to construct the classifier of network communication load state to realize the identification of network communication load state. Finally, the specific data was used to test the performance of network communication load state identification. The test results show that the relevance vector machine can accurately identify the network communication load state, and the correct rate of the network communication load state identification is higher than other models.

In view of the problems of low recognition accuracy and slow speed in current emotion recognition model, we designed an  emotion recognition model based on kernel correlation analysis algorithm. Firstly, the current research status of emotion recognition was analyzed, and the causes of low recognition accuracy were found out. Secondly, the characteristics of emotion recognition was extracted, and the feature subset of emotion recognition was selected by kernel correlation analysis algorithm to reduce the number of feature vectors of emotion recognition. Finally, the Gauss mixture model was used to model the training set of emotion recognition, and the simulation experiments were carried out by the specific emotional data set. The experimental results show that the kernel correlation analysis algorithm can effectively remove the disadvantageous features of emotion recognition, accelerate the speed of emotion recognition, and improve the accuracy of emotion recognition.

In order to solve the problems of high bit error rate and poor communication quality in the current communication system interference signal separation method, we proposed a method of computer communication interference signal separation based on neural network. Firstly, the limitations were pointed out by analyzing the current computer communication interference signal separation. Secondly, the channel model of computer communication system was built, and neural networks was used to optimize and control the stability of computer communication system, and the interference signals were separated. Finally, the simulation experiment was used to analyze the validity and superiority. The results show that the proposed method can separate computer communication interference signal accurately, improve the signal to noise ratio of output signal, and reduce bit error rate of communioation system.

Aiming at the problems of uneven energy consumption and short network life cycle in clustering algorithms for wireless sensor networks, we designed a clustering algorithm for wireless sensor networks with integrated load balancing and energy consumption. Firstly, the nodes were reasonably divided into the corresponding clusters according to the distance between the sensor nodes and the base station nodes. Secondly, the load balancing factor was in
troduced to build data aggregation routing in wireless sensor networks to save data transmission energy. Finally, MATLAB2014 toolbox was used to analyze the performance of clustering algorithm in wireless sensor networks. The results show that the proposed algorithm can improve the energy efficiency of sensor nodes, maintain the balance of energy consumption of sensor nodes, and prolong the lifetime of wireless sensor networks.

In order to resist the quantum attack on users information, on the basis of existing probabilistic cryptosystem, we introduced the idea of probability into multivariate public key cryptosystem and gave a new public key cryptosystem, namely probabilistic multivariate public key cryptography based on unordered sequences. With this method, the sequence of plaintext message was changeless,   the disturbance information was out of order, and the positions of
 them in the constructed plaintext were random. The collision of plaintext message and disturbance information existed in the process of decryption, so recovery of plaintext message might be itself or its subsequence. Both sides of communication should be agreed upon the length of the subsequence of plaintext message in advance when using the public key cryptography. If the contracted number was consistent with the length of the subsequence, the decryption was considered successful.

Aiming at the deficiency of low energy adaptive clustering hierarchy (LEACH) protocol, we proposed an improved routing protocol based on clustering mechanism for dynamic grid transmission and data fusion. The improved protocol established a hierarchical clustering routing structure, used the dynamic grid theory to control the data volume transmission, and applied data filtering algorithm for data fusion. Results of simulation experiments indicate that the improved protocol can effectively reduce the energy consumption of network and extend the lifecycle of network.

The parameters of the water model of the self-consistent charge density\|functional tight\|binding (SCC-DFTB) method  were optimized by using the iterative Boltzmann inversion method.  The results show that the modified water model by iterative Boltzmann inversion method can better agree  with the experimental results, and the  diffusion coefficient of water molecules is closer to the experimental value.

We studied the perturbation of Mei symmetries and adiabatic invariants for dynamical systems with nonstandard Lagrangians. Firstly, we gave the EulerLagrange equation of the system, the criterion equation to Mei symmetry and the exact invariants. Secondly, we gave the differential equations of motion of the system after a small disturbance,  studied the perturbation of Mei symmetry and the adiabatic invariants for dynamical systems under a small disturbance, and obtained the Mei adiabatic invariants of the system after a small disturbance. Finally, we  illustrated the application of the results.

A transversely isotropic cylindrical shell inside filling with water and outside surrounded by a water layer was used to simulate the long bone. The circle acoustic source was located in outer water layer of long cortical bone. The group velocities and the excitation intensities of the guided waves were numerically simulated and analyzed, and the influence of the anisotropic parameters and the inner radius of long bone on the dispersion and the  excitation intensity of guided wave were investigated. The results show that when long bone changes from isotropic into transverse isotropic, the group velocity peaks of high order longitudinal guided wave increase obviously; when the anisotropic parameter \%ε\% decreases, the peak value of group velocity of high order longitudinal guided wave  decreases obviously, and the group velocity curve moves to  the low frequency region; when the anisotropic parameter  \%δ\% decreases, the peak value of group velocity of high order longitudinal guided wave  increases obviously; when the inner radius of long bone increases, and near the low frequency  50 kHz, the group velocity of the lowest order of longitudinal guided wave L01 decreases obviously, and the excitation intensity enhances obviously; the lowest order and the second order longitudinal guided wave can be used to detect the change of thickness of the long bone and anisotropic characteristics, respectively.

We investigated dynamic process of hydrogen bonding of the 1-hydroxy-2-naphthaldehyde (HN12) molecule and molecular isomer in the ground and excited states by means of the density functional theory and timedependent density functional theory. The results show that the hydrogen bond length becomes shorter and the redshift phenomenon of infrared spectrum of the hydroxyl group in the hydrogen bond appears when the HN12 molecule in the ground state is excited to the first electron excited state. The excited state intramolecular proton transfer reactions can take place. The reverse proton transfer reaction is difficult to take place in the excited state, but the reverse proton process is easy to appear in the ground state. There is a cyclic mechanism between the ground state and excited state in the HN12 molecule and the molecular isomer.

Co substrates with different thicknesses were deposited on the Si(100) substrates by magnetron sputtering method, then FeCo/SiO2 thin films were prepared by solgel spincoating combined with hydrogen reduction on the Co underlayers. Crystal structure of the samples were tested by Xray diffractometer, while magnetic properties of the thin films were characterized by vibrating sample magnetometer (VSM). The results show that the crystal orientation of FeCo gradually changes from (110) to (200) with the increase of the thickness of Co underlayers. When the thickness of Co underlayer is 10 nm, the value of I₍₂₀₀₎/I₍₁₁₀₎ is the largest, this indicates that the strongest orientation of FeCo(200) is preferred. At the same time, the inplane saturation magnetization of the film is maximum, and the coercivity is minimum, so the thickness of Co increases which is beneficial to improve the soft magnetic properties of FeCo/SiO₂ composite films.

A pure phase material Na₄MnV(PO₄)₃@C(NMVP@C) was prepared by solgel method, the Na₄MnV(PO₄)₃ was synthesized by graphene, and the JahnTeller effect was inhibited by reducing the content of Mn in the material. Electrochemical performance of materials were tested by  galvanostatic dischargecharge method. The results show that when the Na₄MnV(PO₄)3@C was used as a cathode material for sodium ion batteries,  the specific capacity of 25—40 V was 105 mA·h/g, the average voltage was 3.6 V, and the capacity retention rate after 30 cycles was 63%. The capacity retention rate of composite material after 30 cycles was 71%. The specific capacity of low manganese material Na_3.5Mn_0.5V_1.5(PO₄)3@C was 110 mA·h/g in 25—42 V, and the capacity retention  rate after 50 cycles was 90%. The capacity retention rate of material was greatly improved.

We studied the chiral transition and water solvation effect of two kinds of the most stable configurations of glutamic acid molecules by using the B3LYP method of density functional theory, the MP2 method of perturbation theory, and SMD model method of selfconsistent reaction field (SCRF) theory. The results show that the dominant channels of the configuration one are channel a and channel b, stepdetermining free energy barriers are 242.3, 245.7 kJ/mol, respectively. The dominant channel of the configuration two is the  channel a, and stepdetermining free energy barrier is 243.5 kJ/mol which is generated by the transition state of proton transfer from the chiral carbon to the amino N. The water solvation effect enables the stepdetermining energy barrier is reduced to 101.5 kJ/mol for the dominant channel of the configuration one. The stepdetermining reaction rate is 1.002×10^-5s^-1 at  298.15 K, and it is 3.802×10^-5 s^-1 at 310.00 K. So the  glutamic acid molecules can slowly realize optical isomerism in the life rich water environment.

Using the method of density functional theory B3LYP, we investigated the chiral transition process of the phenylalanine molecule under the cooperative action of dualH₂O at the level of 6-311+G(2-df-). We drew a complete reaction potential energy surface for chiral transition path of phenylalanine molecule by finding the structures of the extreme value points including the transition states and intermediates, and analyzed the geometric and electronic structure properties of extreme value points. The results show that the H atom on the chiral C atom of Sphenylalanine molecule can transfer to the other side of the C atom via the O atoms of carboxyl atoms as a bridge, and achieve the chiral transition of phenylalanine molecule from Stype to Rtype. On this path there are four intermediates and five transition states. The maximum reaction energy barrier is 173.808 1 kJ/mol, which comes from the second transition state TS₂SPhe&2H₂O₂.

By analyzing the structure of aspartate kinase (AK), we screened the Pro184 site that might affect the binding of allosteric inhibitors, and the mutant strain P184Q was successfully screened by saturation sitedirected mutagenesis. The enzymatic properties show that the V_max of P184Q was 3 times higher than that of widetype (WT), n=1.39 indicating that the positive cooperativity of the substrate decreased, the K_m value decreased simultaneously, and the affinity of the substrate increased. The optimum pH of P184Q was 6.5. The optimum temperature of P184Q was
 25 ℃. The halflife period was 2.8 h. Futhermore, P184Q show strong resistance to metal ions, organic solvent and inhibitors Thr+Met, Lys+Met, Thr+Lys and Lys.

We studied the antibacterial effects and mechanism of extracts from Orostachys cartilaginous A.Bor on Salmonella typhoon and Shigella dysenteric. The experimental results show that there are obvious antibacterial effects of ethyl acetate, petroleum ether and chloroform phases on S.typhoon and S.dysenteric. Compared with the control group, the difference is very significant (p<0.01). The minimum inhibitory mass concentration (MIC) of the extracts on the experimental bacteria are obviously different. The MIC of ethyl acetate and petroleum ether extract on S.typhoon are 1.5 mg/mL, and the MIC of ethyl acetate on S.dysenteric is 1 mg/mL. O.cartilaginous A.Bor may inhibit growth of S.typhoon and S.
dysenteric by interfering with the synthesis of cytoderm and inhibition of biofilm formation. The antibacterial effects increase with the increase
of the mass concentration of the extract and the prolonging of the action time.

We obtained the lyophilized products of water extracts by removing oil, water extract, freeze drying pine pollen. The water extracts was diluted with Escherichia coli OP50 to a final mass concentration of 0.5,1.0,2.0 mg/mL to culture Caenorhabditis elegans. By measuring the lifespan, oviposition, swallowing, locomotion of C.elegans, we determined that water extracts of pine pollen had no toxic effects on C.elegans. Through oxidative
stress induced by 10 mmol/L hydrogen peroxide, we determined that 0.5,1.0,2.0 mg/mL water extracts of pine pollen had a significant protective effect on oxidative stress of C.elegans.

The synergistic degradation characteristics of 17β-estradiol (E2) by compound bacteria containing Acinetobacter  LM1 and Pseudomonas LY1 were investigated by using pure and simulated culture methods, respectively. The results show that when the cell number ratio was 1, the degradation rate of E2 by compound bacteria was 2.2 and 2.6 times higer than that of strain LM1 and LY1, respectively, and the cell number ratio of strain LM1 and LY1 tended to be 1 in the process of degradation. The degradation rates of E2 with initial mass concentrations of 1,5,10, 20 mg/L compound bacteria were 99.6%,97%,93%, 85% under conditions of 28 ℃ and 150 r/min, respectively. The degradation rate of E2 was significantly decreased by  compound bacteria when the mass fraction of NaCl was 3.5% in the culture media (p<0.05). The degradation rates of E2 in chicken manure, pig manure and soil samples by compound bacteria were 2.7,3.0 and 2.8 times higer than that of the control group at 25 ℃. Therefore, the compound bacteria composed of strains LM1 and LY1 could degrade E2 by synergistic action.