39 research outputs found
A GaN-based wireless power and information transmission method using Dual-frequency Programmed Harmonic Modulation
Information transmission is often required in power transfer to implement control. In this paper, a Dual-Frequency Programmed Harmonic Modulation (DFPHM) method is proposed to transfer two frequencies carrying power and information with the single converter via a common inductive coil. The proposed method reduces the number of injection tightly coupled transformers used to transmit information, thereby simplifying the system structure and improving reliability. The performances of power and information transmission, and the method of information modulation and demodulation, as well as the principles of the control, are analyzed in detail. Then a simulation model is set up to verify the feasibility of the method. In addition, an experiment platform is established to verify that the single converter can transfer the power and information simultaneously via a common inductive coil without using tightly coupled transformers.Web of Science8498564984
Full-sky ray-tracing simulation of weak lensing using ELUCID simulations: exploring galaxy intrinsic alignment and cosmic shear correlations
The intrinsic alignment of galaxies is an important systematic effect in
weak-lensing surveys, which can affect the derived cosmological parameters. One
direct way to distinguish different alignment models and quantify their effects
on the measurement is to produce mocked weak-lensing surveys. In this work, we
use full-sky ray-tracing technique to produce mock images of galaxies from the
ELUCID -body simulation run with the WMAP9 cosmology. In our model we assume
that the shape of central elliptical galaxy follows that of the dark matter
halo, and spiral galaxy follows the halo spin. Using the mocked galaxy images,
a combination of galaxy intrinsic shape and the gravitational shear, we compare
the predicted tomographic shear correlations to the results of KiDS and DLS. It
is found that our predictions stay between the KiDS and DLS results. We rule
out a model in which the satellite galaxies are radially aligned with the
center galaxy, otherwise the shear-correlations on small scales are too high.
Most important, we find that although the intrinsic alignment of spiral
galaxies is very weak, they induce a positive correlation between the
gravitational shear signal and the intrinsic galaxy orientation (GI). This is
because the spiral galaxy is tangentially aligned with the nearby large-scale
overdensity, contrary to the radial alignment of elliptical galaxy. Our results
explain the origin of detected positive GI term from the weak-lensing surveys.
We conclude that in future analysis, the GI model must include the dependence
on galaxy types in more detail.Comment: 23 pages, 13 figures, published in ApJ. Our mock galaxy catalog is
available upon request by email to the author ([email protected],
[email protected]
Chaos Suppression of an Electrically Actuated Microresonator Based on Fractional-Order Nonsingular Fast Terminal Sliding Mode Control
This paper focuses on chaos suppression strategy of a microresonator actuated by two symmetrical electrodes. Dynamic behavior of this system under the case where the origin is the only stable equilibrium is investigated first. Numerical simulations reveal that system may exhibit chaotic motion under certain excitation conditions. Then, bifurcation diagrams versus amplitude or frequency of AC excitation are drawn to grasp system dynamics nearby its natural frequency. Results show that the vibration is complex and may exhibit period-doubling bifurcation, chaotic motion, or dynamic pull-in instability. For the suppression of chaos, a novel control algorithm, based on an integer-order nonsingular fast terminal sliding mode and a fractional-order switching law, is proposed. Fractional Lyapunov Stability Theorem is used to guarantee the asymptotic stability of the system. Finally, numerical results with both fractional-order and integer-order control laws show that our proposed control law is effective in controlling chaos with system uncertainties and external disturbances
Rabbit Hemorrhagic Disease Virus Non-structural Protein 6 Induces Apoptosis in Rabbit Kidney Cells
Rabbit hemorrhagic disease (RHD) is a highly contagious disease caused by rabbit hemorrhagic disease virus (RHDV). Previous research has shown that RHDV induces apoptosis in numerous cell types, although the molecular mechanisms underlying the apoptosis induced by RHDV are not well understood. One possible factor is non-structural protein 6 (NSP6), a 3C-like protease that plays an important role in processing viral polyprotein precursors into mature non-structural proteins. To fully establish a role for NSP6, the present study examined the effects of ectopic expression of the protein in rabbit (RK13) and human (HeLa and HepG2) cells. We found that NSP6 suppressed cell viability and promoted apoptosis in all three cell types in a dose-dependent manner. We also identified increased caspase-3, -8, and -9 activities in RK13 cell, and an increased Bax to Bcl2 mRNA ratio. Mechanistically, the ability of NSP6 to induce apoptosis was impaired by mutation of the catalytic His27 residue. Our study has shown that RHDV NSP6 can induce apoptosis in host cells and is likely an important contributor to RHDV-induced apoptosis and pathogenesis
RESEARCH ON VARIABLE INERTIA CHARACTERISTICS OF RECIPROCATING CRANKSHAFT SYSTEM TAKEN CONNECTING ROD RATIO INTO CONSIDERATION
Variation of connecting rod ratio in reciprocating crankshaft system can affect the value of system equivalent moment of inertia. However,current traditional variable inertia formula does not consider this important factor,which induces certain errors during torsional vibration analysis. This paper aims to investigate the effects of connecting rod ratio on equivalent moment of inertia and torsional vibration. First,a modified variable inertia formula concerning connecting rod ratio is deduced and its accuracy is compared with traditional one. Then,torsional dynamic equation is established and the method of multiple scales is used to derive the average equation under primary resonance condition. The effects of connecting rod ratio on stable dynamics of the system are investigated. Moreover,traditional and modified variable inertia formulas are compared with exact variable inertia through a detailed single-cylinder crankshaft system. And the shortage of traditional one is pointed out. Finally,numerical results on system vibration characteristic based on different variable inertia formulas are shown to verify the importance of connecting rod ratio on system performances
Recommended from our members
MIQS
Scientific applications often store datasets in self-describing data file formats, such as HDF5 and netCDF. Regrettably, to efficiently search the metadata within these files remains challenging due to the sheer size of the datasets. Existing solutions extract the metadata and store it in external database management systems (DBMS) to locate desired data. However, this practice introduces significant overhead and complexity in extraction and querying. In this research, we propose a novel M etadata I ndexing and Q uerying S ervice (MIQS), which removes the external DBMS and utilizes in-memory index to achieve efficient metadata searching. MIQS follows the self-contained data management paradigm and provides portable and schema-free metadata indexing and querying functionalities for self-describing file formats. We have evaluated MIQS with the state-of-the-art MongoDB-based metadata indexing solution. MIQS achieved up to 99% time reduction in index construction and up to 172kx search performance improvement with up to 75% reduction in memory footprint