Self-Supervised Generative-Contrastive Learning of Multi-Modal Euclidean Input for 3D Shape Latent Representations: A Dynamic Switching Approach

We propose a combined generative and contrastive neural architecture for learning latent representations of 3D volumetric shapes. The architecture uses two encoder branches for voxel grids and multi-view images from the same underlying shape. The main idea is to combine a contrastive loss between the resulting latent representations with an additional reconstruction loss. That helps to avoid collapsing the latent representations as a trivial solution for minimizing the contrastive loss. A novel dynamic switching approach is used to cross-train two encoders with a shared decoder. The switching approach also enables the stop gradient operation on a random branch. Further classification experiments show that the latent representations learned with our self-supervised method integrate more useful information from the additional input data implicitly, thus leading to better reconstruction and classification performance

Catalytic Removal of Ozone by Pd/ACFs and Optimal Design of Ozone Converter for Air Purification in Aircraft Cabin

Ozone in aircraft cabin can bring obvious adverse impact on indoor air quality and occupant health. The objective of this study is to experimentally explore the ozone removal performance of flat-type catalyst film by loading nanometer palladium on the activated carbon fibers (Pd/ACFs), and optimize the configuration of ozone converter to make it meet the design requirements. A one-through ozone removal unit with three different Pd/ACFs space was used to test the ozone removal performance and the flow resistance characteristic under various temperature and flow velocity. The results show that the ozone removal rate of the ozone removal unit with the Pd/ACFs space of 1.5 mm can reach 99% and the maximum pressure drop is only 1.9 kPa at the reaction temperature of 200℃. The relationship between pressure drop and flow velocity in the ozone removal unit has a good fit to the Darcy-Forchheimer model. An ozone converter with flat-type reactor was designed and processed based on the one-through ozone removal experiment, its ozone removal rate and maximum pressure drop were 97% and 7.51 kPa, separately, with the condition of 150℃ and 10.63 m/s. It can meet the design requirements of ozone converter for air purification and develop a healthier aircraft cabin environment

Strongly interacting Bose-Fermi mixture: mediated interaction, phase diagram and sound propagation

Motivated by recent surprising experimental findings, we develop a strong-coupling theory for Bose-Fermi mixtures capable of treating resonant inter-species interactions while satisfying the compressibility sum rule. We show that the mixture can be stable at large interaction strengths close to resonance, in agreement with the experiment but at odds with the widely used perturbation theory. We also calculate the sound velocity of the Bose gas in the $^{133}$Cs-$^6$Li mixture, again finding good agreement with the experimental observations both at weak and strong interactions. A central ingredient of our theory is the generalization of a fermion mediated interaction to strong Bose-Fermi scatterings and to finite frequencies. This further leads to a predicted hybridization of the sound modes of the Bose and Fermi gases, which can be directly observed using Bragg spectroscopy.Comment: 13 pages, 10 figure

Toll-like receptor activation by helminths or helminth products to alleviate inflammatory bowel disease

Helminth infection may modulate the expression of Toll like receptors (TLR) in dendritic cells (DCs) and modify the responsiveness of DCs to TLR ligands. This may regulate aberrant intestinal inflammation in humans with helminthes and may thus help alleviate inflammation associated with human inflammatory bowel disease (IBD). Epidemiological and experimental data provide further evidence that reducing helminth infections increases the incidence rate of such autoimmune diseases. Fine control of inflammation in the TLR pathway is highly desirable for effective host defense. Thus, the use of antagonists of TLR-signaling and agonists of their negative regulators from helminths or helminth products should be considered for the treatment of IBD

The Design of High Performance, High Resolution Two-Order Delta-Sigma Modulator

The design of single loop two-order Delta-Sigma modulator with feed forward structure is presented in this thesis. Oversampled analog-to-digital converters based on second-order delta-sigma modulation are attractive for VLSI implementation because they are especially tolerant of circuit nonidealities and component mismatch. The noise shaping and oversampling are used in this modulator, the oversampling rate (OSR) is 256 and the resolution could be reached 14 bits. The integrally design of Delta-Sigma modulator is argued in deep in the paper, since the behavior model is tested efficiently by Simulink, the time of design has been cut to the bone. As the fully differential structure is used, the system to inhibit the ability of common-mode interference improved and the sampling rate is also raised, the fully differential switching capacity structure is used in the circuit design of modulator. And because of the fully differential structure, the input noise is reduced, the output slewrate of op-amp is greatly improved and the whole circuit is more stable. The 0.5 ?m CMOS process is used in simulation of circuit, the results of simulation are shown that the amplifier gain is 82.3 dB, the Phase Margin is 71.34°, the output slewrate of op-amp is 202 V/?s, the unit GainBandWidth is 102 MHz. the whole circuit of modulator is tested with 10.24 MHz of the clock frequency, the SNDR reached to 93.2 dB, the Dynamic Range (DR) is 100 dB. In summary, this Delta-Sigma modulator could be used in Portable, Audio system and so on