This paper studies the threshold characteristic of epidemic on complex networks with given degree distribution and obtains the critical condition for a major outbreak of epidemic. In a minor outbreak situation, we derive the distribution and the mean size of connected branch of such network. We also obtain the scale of a major outbreak, i.e. the ratio of the number of vertices in a huge branch to the total number of vertices in the network.

A supersaturated design is essentially a factorial design with the equal occurrence of levels property and no fully aliased factors in which the number of main effects is greater than the number of runs. It attracts a lot of interest because of its potential in factor screening experiments. The construction and analysis of symmetrical supersaturated designs have been widely explored, while asymmetrical (or mixed-level) supersaturated designs deserve further investigation. The main purpose of this article is to provide constructing methods for E(f_NOD)-optimal mixed-level supersaturated designs. We use a E(f_NOD)-optimal design and an orthogonal array (OA) to construct a new E(f_NOD)-optimal supersaturated designs with more mixed-level factors.

There are some certain relationships between the financial market and the physical world. The fluctuation of security price shows a certain characteristic of particle behavior. Firstly, we summarize the square potential well in quantum physics, and extend the objective law to more general and complex ones. Then we solve the transcendental equation by MATLAB, and deduce the numerical solution of the wave function and its probability distribution image. Lastly, we use one dimensional unsymmetrical finite deep square potential well to fit the rate of return of Shanghai Stock Index. We find that the fitting effect is satisfactory, and the volatility of Stock Index has some rich physical connotations. This research could enrich the results of Econophysics, and has important enlightenment to capital market construction and risk management.

When the portfolio is regarded as a moving point in the “risk-return” plane, we can use the running track of the portfolio in the plane to describe its past historical performance and future trend. The interaction effect between the two portfolios can also be seen as “gravitation”. The theoretical analysis shows that when we select the proper alignment and focus point, the running track of the moving point is conic section, due to the common effect by the focus point “gravitation” attraction and its velocity. The empirical result is acceptable. According to the eccentricities classification of 66 portfolios, the classification result shows that most of stock funds and hybrid funds are elliptical funds, the monetary fund are parabolic funds, most of bond funds are hyperbolic funds. The upper branch of parabola can not fit all the scattered points very well, in need of classification fitting. We use Sharpe ratios to evaluate the performance of the portfolios. The result shows that Sharpe ratios is positively correlated with the eccentricities. Finally, according to physics, the “gravitational constant” can be determined by using the velocity rate formula when the elliptical fund runs to the top of the elliptic orbit. The gravitational constant G₀ is 1.72×10^-14 (λ^－3·week^－2·yuan^－1).

By traveling wave reduction, the Phi-4 equation u_tt-u_xx+m²u+λ u³=0 can be transformed into the complex ordinary equation (c²-1)(w′)²+m²w²+λ2w⁴+μ=0. Then by the complex method, we obtain new meromorphic general solutions containing elliptic solutions and its degeneration. Compared with other results on the Phi-4 equation, our conclusion is that the complex method is a powerful and effective mathematical tool for surveying exact traveling wave solutions for some nonlinear partial differential equations.

Machine learning algorithms are widely used in the field of medical oncology. In this paper, the four classic algorithms, including logistic regression, artificial neural network, support vector machine and AdaBoost methods, are applied to the patients with pulmonary adenocarcinoma ground nodules. The comparison and analysis of model performance, on accuracy, sensitivity, specificity, F1-score and G-score parts, shows that the accuracy of the four models is more than 85% while the clinician is only 78% in diagnosis. We obtain the characteristics of different models: the back propagation neural network has the highest accuracy and has strong self-learning ability, support vector machines need to adjust the parameters to optimize the model and the training effect from SVM is better for small samples. Logistic regression does not require parameters adjustment, but it is time-consuming to train under large samples. AdaBoost has the good quality of combining multiple models before making a diagnosis, which provides the clinician with a preoperative diagnosis plan.

The microwave extraction of Champagne were optimized by single factor test with the extraction time, microwave power and liquid-solid ratio as process parameters. The results showed that the optimum process parameters were microwave power 1 000 W, liquid-solid radio 1∶10 g·mL^-1 and time 40 min.Compared with the traditional water extraction method, the microwave treatment increases the extraction rate of active ingredients in champagne by 1.75 times. The technology of extracting Champagne using microwave technology has good stability, short extraction time and high extraction efficiency. In addition, the microwave extraction mechanism of Chinese medicine were investigated by observing the microstructure of the cell through SEM.

It is of great importance to establish an effective method that provids scientific references for clinical research to determine simultaneously multi-targets in human serums with clinical background data which are difficult to get. To get accurate phthalates (PAEs) content in human serums, the removal of high background pollution and interference has become the key problem. In this study, the effects of different interference factors on the blank background were investigated. The results showed that the background of the blank was affected seriously by the solvents, materials, sample concentration methods and so on. Owing to the high background pollution, the results of PAEs content are inaccurate in serums. Some measures were taken to reduce the interferences on the determination of PAEs, such as using freshly prepared eluent, reducing the sample exposure time to the air, using silica gel that had been extracted,activated and deactivated in turn, and using silica gel column made of glass. Thereby, a stable and reliable method has been established for the determination of multi-targets in human serums.

Vibration induced by pedestrian loading of a suspension floor in a venue building is studied and controlled by tuned mass damper in this paper as its vertical frequency lies in the range of the pedestrian load. A simplified floor model was proposed and verified by comparison of dynamic characteristics with the original overall structure to save computational time. The design parameters and installation locations of the tuned mass dampers were determined based on optimal control design principles. Dynamic responses of the simplified suspension floor with and without tuned mass damper under 12 kinds of pedestrian cases, such as general random pedestrian cases, extremely random pedestrian cases, beat and jump pedestrian cases, were investigated in detail. Results show that the peak acceleration responses of the floor without damper are much bigger than the limit requirement. However, the vibration responses are effectively controlled by the optimal designed tuned mass damper and up to 61% of the damping effect is achieved. In addition, although the displacement responses of the floor are very small and can be ignored in pedestrian loadings, good control effect can also be found by using the tuned mass damper. This paper sheds some lights on vibration control of similar engineering problems.

In order to analyze the influence of oil inflow and property parameters on the flow state of oil-water core annular flow in ball valves, the VOF model was used to track the oil-water interface, and the turbulent flow was described by standard turbulence k-ε model. The oil phase volume fraction, the pressure difference at both ends, and distance of oil adhere to pipe-wall under different oil velocity and oil phase properties were analyzed. The results show that the oil phase flow velocity increases, the volume fraction of oil phase increases and then tends to a certain value, the pressure difference at both ends of the valve presents an upward trend. With the increase of oil phase viscosity, oil phase volume fraction increases, pressure difference at both ends of the valve massses, and the distance adhered to wall decreases.

A dynamic collaborative harmony search algorithm is studied and applied to the perceptual model of wireless sensor networks. The proposed algorithm devises a multi-population dynamic collaborative evolutionary strategy for improving the algorithm diversity. In the harmony memory consideration phase, the roulette selection are employed to enhance the searching effectiveness. Meanwhile, the key parameters are adjusted dynamically for improving the overall performance of the original harmony search algorithm. The optimization problem of wireless sensor network coverage optimization is optimized, and the results show that the proposed algorithm has achieved better results.

A solid carbon source biofilm reactor with corncob as filler was used to treat low C/N ratio wastewater by simultaneous nitrification and denitrification (SND) technology. The effect of different hydraulic loadings and C/N ratio on the denitrification effect of the system was investigated. The surface morphology of the corncobs was detected before and after the biofilm formation. The results show that the average removal rates of NH⁺₄-N and TN are 92.16% and 91.18%, respectively, at the hydraulic loading of 0.045 m³·m^-2·h^-1. When the influent C/N ratio is controlled between 0 and 12, the effluent COD_Cr concentration is below 50 mg·L^-1, and the average TN removal rate is above 79.63%. The denitrification effect increases with the increase of the C/N ratio. Scanning electron microscopy shows that corn cob is a better solid carbon source biofilm reactor packing, suitable for denitrification treatment of urban sewage with low carbon and nitrogen ratio.

Through the traditional methods of bibliometrics and Cite-Space software, the paper analyzes the literature output time, keywords, authors and agencies of the “Life-Production-Ecological Space” study. Finally, the paper summarizes the research hotspots and status quo of the existing “three-life space” literature. It draws the results: ①Domestic research on “three-life space” first appeared at the end of the 20th century. In 2012, it became a research hotspot. The number of documents has increased rapidly and has remained stable in recent years. ②There are many researchers in this field, and Fan Jie has published the most literature. ③The Institute of Geographic Sciences and Natural Resources Research of the Chinese Academy of Sciences has the highest frequency of publication, and it is at the center of the cooperation network of scientific research institutions. There are more cooperations with institutions in the same city or in the same sector, and there is less cross-regional and interdisciplinary cooperation. ④In recent years, the “three-life space” research has the characteristics of multi-disciplinary and multi-scale research methods. The research content mainly focuses on the construction of the theoretical framework, classification, evaluation and optimization of “three-life space.”

Combing the catalog of national-level mass innovation space, with the help of geostatistics and social statistical methods, this paper analyzes the distribution characteristics of mass innovation space on province and city scale. The results show: ①Spatial distribution of mass innovation spaces has obvious characteristics of the diffusion zone along the north-south direction. The interregional differences are large and it shows a significant clustering feature; ②The distribution of mass innovation spaces present positive spatial autocorrelation at the urban scale.It also shows high agglomeration and high and low aggregation; ③The comprehensive social and economic conditions of the city have a certain impact on the total amount of spaces created by the public, among which the conditions of science, technology and education affect the growth rate of the public space, and the degree of development of the service industry and the industrial structure have a great influence on the distribution of the public space; ④Policy, location, industry, functional positioning, the development of a comprehensive environment and other factors together promote the mass innovation spaces gathering. But in different cities and at different stages of development of mass innovation space, the impact of these factors has a great difference.

The definition of intrapreneurship widely refers to the existing organization business. Due to the international and domestic market competition, organizational entrepreneurship has become an important factor affecting the organization and social economic development. This review analyzes the internal business concept formation, entrepreneurship dimension effect machine factors entrepreneurship and entrepreneurship with a bearing to the future research.