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Hybrid low-density parity-check (LDPC) decoding combines conventional Belief-Propagation (BP) algorithm with stochastic decoding to achieve high performance and low complexity simultaneously. However, lossy and inefficient stochastic-to-binary (S2B) conversion brings extra performance degradation and decoding latency. In this paper, a bit-serial stochastic updating based hybrid decoding (BSSU-HD) is proposed, which employs fully correlated stochastic (FCS) check nodes (CNs) and probability tracers assisted variable nodes (VNs) to accomplish accurate and efficient S2B conversion. Two strategies, including random source selection and tracing speed switching, are proposed to further improve performance and convergence. A BSSU LDPC decoder for IEEE 802.3an is designed in a 65-nm CMOS process, which occupies 4.6 mm2 silicon area and achieves a throughput of 200.8 Gb/s at $E_{b}/N_{0} = 4.4$ dB with 500 MHz clock frequency from a 1.2 V supply voltage. The power and energy efficiency are 2.933 W and 14.61 pJ/bit, respectively. To the best of our known, it achieves the best decoding performance, the highest throughput and hardware efficiency among state-of-the-art IEEE 802.3an LDPC decoders. We also verify that the BSSU-HD can achieve better performance for multi-rate 5th generation (5G) New Ratio (NR) LDPC codes than conventional algorithm, which greatly extends the application of the stochastic decoding.

• Two sliding-mode observers are proposed to deal with the uncertainties of the teleoperation system. Finite time estimation can be realized with the proposed observers. • A novel power reaching law is proposed to construct the sliding-mode observer for uncertain kinematics with faster reaching time and larger range of parameter. • Finite time convergence of the tracking errors in teleoperation system and stability of the closed-loop system can be guaranteed with the proposed NTSMC scheme. This study concentrates on the tracking control of teleoperation system subjected to robot uncertainties. The coupling of kinematic and dynamic uncertainties poses a challenge to construct the teleoperation controller. To overcome this difficulty, an observer-based approach is designed to ensure position tracking while compensating for the unfavorable effects arising from the uncertainties. First, two sliding-mode observers together with a novel power reaching law are constructed, upon which, the uncertainties will be estimated in finite time. Next, a controller is proposed to solve the finite-time convergence of the tracking errors. The settling time and the stability of the closed-loop system are derived by Lyapunov's direct method. Simulation results are presented to testify the tracking performance of the suggested control. [ABSTRACT FROM AUTHOR]

Identifying novel strategies to prevent particulate matter (PM)-induced lung injury is crucial for the reduction of the morbidity of chronic respiratory diseases. The combined intervention represented by herbal formulae for simultaneously targeting multiple pathological processes can provide a more beneficial effect than the single intervention. The aim of this paper is therefore to design a safe and effective medicinal and edible Chinese herbs (MECHs) formula against PM-induced lung injury.

The ultra-low hardware consumption feature of stochastic decoding has made it a potential candidate for the implementation of low-density parity-check(LDPC) decoders. However, the existing stochastic LDPC decoders still suffer from performance degradation and relatively high decoding cycles caused by the correlation among stochastic bit streams. In this paper, we propose Hybrid Stochastic(HS) decoding, which achieves high performance, high throughput, and high hardware efficiency by jointly using our proposed novel stochastic check node(CN) and Two’s Complement(TCS) variable node(VN) to realize Min-Sum Algorithm(MSA) and its enhancements. Fully correlated stochastic bit streams are used to entirely eliminate the indeterminacy caused by the correlation, which results in high performance and fast convergence and inherits the low complexity of stochastic decoders at the same time. We demonstrate the HS decoding by designing a (2048,1723) decoder in a 65 nm process, which achieves the highest Bit-Error-Ratio(BER) performance, highest throughput, and top hardware efficiency among existing stochastic LDPC decoders. We also demonstrate that HS decoding can achieve excellent decoding performance for different code rates and lengths 5G New Radio(NR) LDPC codes. Thus, HS decoding can be adopted in wide applications. [ABSTRACT FROM AUTHOR]

We report a new, to the best of our knowledge, measurement method of optical rotatory dispersion (ORD) based on a polarization axis finder (PAF) and digital image processing. The collimated quasi-monochromatic light is output by a monochromator and passes through a polarizer and the chiral samples, and a PAF is employed to modulate the light beam spatially to form an “hourglass” intensity pattern, which is utilized to determine the polarization direction of linearly polarized light. After being recorded by a digital camera, the modulated patterns with and without samples are analyzed by our specially designed digital image processing program to calculate the optical rotation (OR) angle of the chiral substance at a certain wavelength, and the ORD curve can be obtained by fitting a series of OR angles with different wavelengths. The ORD curves of two standard quartz plates with opposite chirality and a glucose solution with different concentrations are measured experimentally, and the fitted coefficients and measurement results agree well with their theoretical values, which indicates that the presented method is an effective and accurate way to determine the ORD of chiral substances conveniently.

As a result of the high theoretical energy density of lithium–sulfur (Li–S) batteries, they have been accepted as the next-generation energy storage system. Nevertheless, the current performance of Li–S batteries is still unsatisfactory under lean electrolyte conditions. It is because of sluggish deposition of Li2S2/Li2S passivating the sulfur/electrolyte interface, thus leading to lower sulfur use and bad rate performances of Li–S batteries. Herein, a novel Co9S8nanorod-based catalytic interlayer placed between the cathode and separator is proposed. The interlayer possesses a three-dimensional open structure, which facilitates electrolyte infiltration but without trapping too much electrolyte. As a result, the electrocatalytic Co9S8nanorods within the interlayer promote faster electrochemical kinetics and enhance the conversion of polysulfides, thus resulting in a higher specific discharge capacity and better rate and cycling performance. This work proves a feasible method in developing practical Li–S batteries.

This paper is concerned with the image-based visual servoing (IBVS) control for uncalibrated camera-robot system with unknown dead-zone constraint, where the uncertain kinematics and dynamics are also considered. The control implementation is achieved by constructing a smooth inverse model for dead-zone-input to eliminate the nonlinear effect resulting from the actuator constraint. A novel adaptive algorithm, which does not require a priori knowledge of the parameter intervals of dead-zone model, is proposed to update the parameter values online, and the dead-zone slopes are not required the same. Furthermore, to accommodate the uncertainties of uncalibrated camera-robot system, adaptation laws are developed to estimate the uncertain parameters, simultaneously avoiding singularity of the image Jacobian matrix. With the full consideration of unknown dead-zone constraint and system uncertainties, an adaptive robust visual tracking control scheme together with dead-zone compensation is subsequently established such that the image tracking error converges to the origin. Based on a 3-DOF manipulator, simulations are conducted to verify the tracking performance of the proposed controller. [ABSTRACT FROM AUTHOR]

Lithium metal is an ideal anode material for next-generation electrical energy storage because of its high specific capacity. However, uncontrolled growth of Li dendrites during deposition and stripping processes results in low coulombic efficiency and severe safety concerns. Here we report a porous and robust coating of metal-organic framework (MOF-199), which could physically suppress the growth of lithium dendrite by acting as a robust shield, and homogenize Li-ion concentration by its high-polarity structure, thereby relieving excess SEI formation. In addition, another MOF (ZIF-8) layer is also confirmed to effectively hinder the formation and penetration of Li dendrites. The MOF particle size in the coating layer is shown to be a key factor determining the level of protection. Finally, the ability of the MOF-199 layer to protect Na metal anodes is studied.

In this paper, the problem of neural network control for visual servoing robotic system is addressed, where the unmodeled dynamics and output nonlinearity are taken into account simultaneously. An adaptive neural network module is constructed to approach the unknown dynamics, upon which, the robot dynamics are not required to be linearly decomposable and structurally known. The major superiority of this module lies in its conciseness and the computational-reduction operation. Moreover, the output nonlinearity is considered, and its undesirable effect is subsequently tackled without a prior knowledge of the model parameters in output mechanism. It is proven by the Lyapunov method that the image-space tracking error is driven to an adjustable neighborhood of origin. Numerical simulations and experiments under various situations are used to validate the performance of the proposed adaptive neural network based scheme. [ABSTRACT FROM AUTHOR]

Considering the market demand for lithium‐ion batteries (LIBs) and sodium‐ion batteries (SIBs) as energy storage devices, it is necessary to find a negative electrode material with low cost, high specific capacity, and long cycle life. CuO has a high theoretical specific capacity and therefore has broad application prospects. This study reports a freestanding nitrogen‐doped carbon‐coated CuO array (NC‐CuO)‐based anode obtained by synthesizing CuO nanorods on a Cu net and depositing nitrogen‐doped carbon on the surface of the nanorods. The NC‐CuO array anode fully utilizes the synergistic advantages of the 3D array and the outer N‐doped carbon layer, which effectively enhance the electronic conductivity of the metal oxide and alleviate the volume change during Li/Na ion insertion and extraction. It is found that the NC‐CuO array as the anode material for LIBs has a capacity of 562.5 mAhg−1and a cycle stability of more than 200 cycles even at a high current density of 500 mAg−1. SIBs with the NC‐CuO array anode also exhibit excellent electrochemical performance. A freestanding nitrogen‐doped carbon‐coated CuO (NC‐CuO) array is obtained by synthesizing CuO nanorods on a Cu net and depositing nitrogen‐doped carbon outside the nanorod surface. The NC‐CuO array anode fully utilizes the synergistic advantages of the 3D array and the outer carbon layer, which enhance the electronic conductivity of the metal oxide and alleviate the volume change during Li/Na ion insertion and extraction.