Break The Spell Of Total Correlation In betaTCVAE

In the absence of artificial labels, the independent and dependent features in the data are cluttered. How to construct the inductive biases of the model to flexibly divide and effectively contain features with different complexity is the main focal point of unsupervised disentangled representation learning. This paper proposes a new iterative decomposition path of total correlation and explains the disentangled representation ability of VAE from the perspective of model capacity allocation. The newly developed objective function combines latent variable dimensions into joint distribution while relieving the independence constraints of marginal distributions in combination, leading to latent variables with a more manipulable prior distribution. The novel model enables VAE to adjust the parameter capacity to divide dependent and independent data features flexibly. Experimental results on various datasets show an interesting relevance between model capacity and the latent variable grouping size, called the "V"-shaped best ELBO trajectory. Additionally, we empirically demonstrate that the proposed method obtains better disentangling performance with reasonable parameter capacity allocation

SIRT1 (sirtuin (silent mating type information regulation 2 homolog) 1 (S. cerevisiae))

SIRT1 is a member of the mammalian sirtuin genes that encode for seven protein lysine modifiers with deacetylase, ADP-ribosyltransferase and other deacylase activities. SIRT1 plays diverse roles in regulating cell proliferation, differentiation, stress response, metabolism, energy homeostasis, aging and cancer. Besides deacetylating histone substrates, SIRT1 regulates functions of an array of non-histone proteins including transcriptional factors for gene regulation, DNA repair machinery elements for reducing catastrophic genome lesions, epigenetic factors for chromatin and gene regulation, nuclear receptors and circadian clock as well as related factors for metabolism, and other cell signaling molecules. SIRT1 is involved in many types of human cancer

The coherent sound field separation method combining compressive sensing

When multiple coherent sound sources are distributed on the same side of the holographic surface, the conventional method must use known information such as sound source distribution and geometry. In view of this situation, a method of coherent sound field separation combined with compressive sensing is proposed. The method is based on the plane equivalent source near-field acoustic holography method and the orthogonal matching pursuit algorithm of compressive sensing technology. Get the distribution of the virtual sound source on the plane, and then the virtual sound sources are grouped and selected. Finally, the distribution of sound pressure in the near-field plane after separation of the sound field is calculated using the conduction matrix. The method does not require other prior knowledge. The simulation results show that this method can be used as an effective complementary method for coherent sound field separation based on single-sided measurement

Ex Perimental Study on Water Absorption of Coal Under Different Pressure Source Conditions

AbstractIn order to study the effect of pressure on the water absorption capability of coal, the water injection experiments of two coal samples were done under different pressure source conditions and room temperature by using self-designed pressurized water device. The experimental results show that pressure has a positive effect on water absorbability; water absorbability gets large as the pressure increases; the earlier water absorbability of coal is rapid, and the water absorbability of coal displays a similar Langmuir-isothermal adsorption curve with the changes of time, and it has saturated water absorbability. The water injection pressure is higher, which not only strengthened the ability of expanding seepage space, but also developed the transporting water and storage water space. The later water absorption curve of coal becomes weaker, and water adsorption process is mainly influenced by capillary force. The pressure water only supplies provisions and time is the main influential factor

Source localization in reverberation environment based on improved equivalent sound source near-field acoustic holography algorithm

The compressive-equivalent source method near-field acoustic holography (C-ESM) is disturbed by reverberation in the enclosed space such as room and cabin, which leads to large reconstruction error and disturbs the judgment of sound source position. In order to solve this problem, an improved C-ESM algorithm based on room impulse response (RIR) is proposed to filter out reverberation interference in this paper. Different from the original equivalent source method, the improved algorithm constructs the transfer function through the room impulse response to establish the relationship between the equivalent source and the sound pressure on any plane in space, and the sparse signal reconstruction method of the compressive sensing technology is used to obtain the strength of the equivalent source. Then the transfer function to any plane of space is established according to the free field Green’s function, to eliminate the interference of reverberation and improve the effect of sound source location. The accuracy and effectiveness of the improved method are verified by preliminary numerical simulation. And the results show that compared with the original algorithm, this method has obvious advantages in sound source localization in a reverberant field

Numerical simulations of the sliding impact between an ice floe and a ship hull structure in ABAQUS

This paper studies the hull structural responses of a steel grillage subjected to sliding ice loads, which have been rarely investigated in the literature. Sliding ice loads are modelled using nonlinear finite element analysis (NLFEA) method; and Abaqus Explicit is adopted as the numerical solver. Deformations and damages of ice and steel are both considered. A rigid ice model is also simulated for comparison purposes. The hull’s local structural responses under different load cases, including deformation, contact forces, and energy distribution, have been analysed. The effects of static structure-to-structure friction coefficient and the relative stiffness between ice and structure are studied. It is found that the deformation of structures will increase the total friction coefficient, which is defined as the ratio of the friction force (the tangential contact force) to the normal contact force. When the ice floe is considered rigid, the static friction coefficient has little effect on the local structural responses of the hull. If using a higher-strength steel material for hull structures in the ice-classed ship design, the hull’s deflection and total friction decrease, and the hull dissipates less energy as expected. Moreover, stationary load cases with the same loading condition in the normal direction as sliding load cases are also simulated. When using the deformable ice material model, the simulation results show that the hull’s final contact forces and deflection in stationary load cases are larger than those in sliding load cases. Besides, the effect of steel material is more significant in stationary load cases than in sliding load cases.publishedVersio

An improved stability criterion for linear time-varying delay systems

This paper considers the stability problem of linear systems with time-varying delays. A modified Lyapunov–Krasovskii functional (LKF) is constructed, which consists of delay-dependent matrices and double integral items under two time-varying subintervals. Based on the modified LKF, a less conservative stability criterion than some previous ones is derived. Furthermore, to obtain a tighter bound of the integral terms, the quadratic generalized free-weighting matrix inequality (QGFMI) is fully applied to different delay subintervals, which further reduces the conservatism of the stability criterion. Finally, three numerical examples are presented to show the effectiveness of the proposed approach