Abstract: A lightweight, ballistic and blast-resistant multi-phase composite armor material based on a high-toughness heterogeneous interfacial layer, including a crack-arresting layer, a bullet-breaking layer, an energy-absorbing layer, and a support layer. The crack-arresting layer, the bullet-breaking layer, the energy-absorbing layer, and the support layer are stacked in sequence from a bullet-accepting side to the inside. Adjacent two layers are bonded with an adhesive film layer. The crack-arresting layer and the support layer are both made of a carbon fiber composite. The bullet-breaking layer is made of ceramic. The energy-absorbing layer is made of an ultra-high molecular weight polyethylene fiber composite. The adhesive film layer is made of a high-toughness heterogeneous interfacial adhesive.

Abstract: A current-to-voltage conversion circuit used in a digital isolator. The current-to-voltage conversion circuit has an input terminal to receive an input current, an output terminal to output a power supply voltage generated based on the input current. The current-to-voltage conversion circuit has an operational amplifier and a voltage regulation switch device, the voltage regulation switch device has a control end coupled to an output end of the operational amplifier. When the input current is less than an adjustment threshold, the voltage regulation switch device is turned off, and when the input current is greater than the adjustment threshold, the voltage regulation switch device is turned on.

Abstract: An optimizing method for a molding process of a part made of a fiber-reinforced polymer composite is provided. A finite element method is adopted to perform thermochemical analysis of a macroscopic model of the part and thermomechanics analysis of a microscopic model of the part, so as to simulate temperature gradient, curing degree, and residual stress of the part during the molding process. A genetic algorithm is executed, with simultaneous minimization of temperature gradient, molding time, and residual stress as an optimization goal and a curing process curve as a parameter variable, to achieve the simultaneous multi-objective optimization of molding process parameters, so as to obtain an optimized molding process.

Abstract: The present invention discloses a differential signal amplification circuit as well as a digital isolator and a digital receiver applying the differential signal amplification circuit, wherein the differential signal amplification circuit includes a multi-stage differential amplifier and a common-mode transient adaptive biasing circuit. The common-mode transient adaptive biasing circuit is configured to detect a positive or negative common-mode transient interference signal at a positive input terminal and a negative input terminal, and provide a biasing current of a differential amplifier of at least one stage above a second stage when the positive or negative common-mode transient interference signals are detected. With the technical solutions of the present invention, abnormal signal transmission caused by the common-mode interference signals can be suppressed.

Abstract: A thermal compensation design and implementation method for near-net-shape molding of a thermoset composite part based on temperature and curing degree fields is provided. A minimum symmetric unit model is established based on sizes of the part and a mold and ambient temperature. A curing kinetic model and a heat transfer model are established. A molding temperature curve is written into a subprogram. A simulated thermal compensation is performed on a region whose temperature is lower than a molding temperature with a difference of greater than or equal to 5% of the molding temperature until the temperature difference of individual regions is less than 5% of the molding temperature. The simulated thermal compensation is then performed on those regions with a curing degree less than or equal to 0.9. A thermal compensation device is assembled according to the thermal compensation scheme for experimental verification.

Abstract: An high-velocity impact-resistant wave-transparent composite, including an upper composite layer, a lower composite layer, and a bio-inspired nacre-like toughening structure arranged therebetween. The toughening structure has a soft-hard alternating nacre-like structure, and is made from a low dielectric constant sheet material and a resin. The upper composite layer and the lower composite layer are each independently made of a fiber-reinforced resin composite, a foam material, or a honeycomb material. A preparation method of the high-velocity impact-resistant wave-transparent composite is further provided.

Abstract: An optimization method for molding mold and filling process of resin transfer molding (RTM) to form fiber fabric reinforced resin-based composite parts is provided. A simulation platform is used to simulate the mold filling process of RTM process. Brinkman equations are used to describe a flow of resin in fiber fabric. Numbers and positions, process parameters and material parameters of an injection gate and a discharging gate of the molding mold are set, and then the mold filling process is simulated. Darcy's law is utilized to determine a required time and a mold filling effect of the mold filling with the resin. Finally, a molding mold structure and the filling process of RTM to form fiber fabric reinforced resin-based composite part with high production efficiency and good quality are obtained.

Abstract: A thermal compensation design and implementation method for near-net-shape molding of a thermoset composite part based on temperature and curing degree fields is provided. A minimum symmetric unit model is established based on sizes of the part and a mold and ambient temperature. A curing kinetic model and a heat transfer model are established. A molding temperature curve is written into a subprogram. A simulated thermal compensation is performed on a region whose temperature is lower than a molding temperature with a difference of greater than or equal to 5% of the molding temperature until the temperature difference of individual regions is less than 5% of the molding temperature. The simulated thermal compensation is then performed on those regions with a curing degree less than or equal to 0.9. A thermal compensation device is assembled according to the thermal compensation scheme for experimental verification.

Abstract: The present invention provides a common-mode transient suppression protection circuit for a digital isolator, including a modulation circuit, a demodulation circuit and an isolation capacitor connected between the modulation circuit and the demodulation circuit. The modulation circuit includes a modulation circuit front-end and a drive circuit, which are connected in sequence, and a clamping module is arranged in the drive circuit. The protection circuit further includes a linear voltage regulator structure connected with the drive circuit, and a power supply clamp is arranged in the linear voltage regulator structure. By providing the linear voltage regulator structure having the power supply clamp and the drive circuit having the clamping module in the protection circuit, low-voltage devices in the drive circuit can be protected from being damaged by high-voltage signals generated by common-mode transient interference.

Abstract: An optimizing method for a molding process of a part made of a fiber-reinforced polymer composite is provided. A finite element method is adopted to perform thermochemical analysis of a macroscopic model of the part and thermomechanics analysis of a microscopic model of the part, so as to simulate temperature gradient, curing degree, and residual stress of the part during the molding process. A genetic algorithm is executed, with simultaneous minimization of temperature gradient, molding time, and residual stress as an optimization goal and a curing process curve as a parameter variable, to achieve the simultaneous multi-objective optimization of molding process parameters, so as to obtain an optimized molding process.

Abstract: An high-velocity impact-resistant wave-transparent composite, including an upper composite layer, a lower composite layer, and a bio-inspired nacre-like toughening structure arranged therebetween. The toughening structure has a soft-hard alternating nacre-like structure, and is made from a low dielectric constant sheet material and a resin. The upper composite layer and the lower composite layer are each independently made of a fiber-reinforced resin composite, a foam material, or a honeycomb material. A preparation method of the high-velocity impact-resistant wave-transparent composite is further provided.

Abstract: A lightweight, ballistic and blast-resistant multi-phase composite armor material based on a high-toughness heterogeneous interfacial layer, including a crack-arresting layer, a bullet-breaking layer, an energy-absorbing layer, and a support layer. The crack-arresting layer, the bullet-breaking layer, the energy-absorbing layer, and the support layer are stacked in sequence from a bullet-accepting side to the inside. Adjacent two layers are bonded with an adhesive film layer. The crack-arresting layer and the support layer are both made of a carbon fiber composite. The bullet-breaking layer is made of ceramic. The energy-absorbing layer is made of an ultra-high molecular weight polyethylene fiber composite. The adhesive film layer is made of a high-toughness heterogeneous interfacial adhesive.

Abstract: Provided is a preamplifying circuit, including a first amplifier and a second amplifier sequentially connected in series, wherein an output end of the second amplifier is connected to a circuit output end, and an input end of the first amplifier is connected to a circuit input end. The preamplifying circuit further includes a positive feedback branch including a diode group and a third amplifier, wherein one end of the diode group is connected to the input end of the first amplifier. The positive feedback circuit can positively feed part of signals back to the other end of the diode group, so that voltage drops at two ends of the diode group can be reduced, and harmonic distortion caused by nonlinearity of the diode group is reduced. Thus, the sound quality detected by a microphone sensor is improved.

Abstract: Provided are a low-jitter digital isolator circuit and a digital isolator including the same. The digital isolator circuit includes a signal transmitting module, a signal receiving module, and an isolation channel connected between the signal transmitting module and the signal receiving module. The signal transmitting module is provided with a signal input terminal, and the signal receiving module is provided with a signal output terminal. The signal transmitting module includes a reset circuit, an oscillator and a transmitting circuit which are sequentially connected. The reset circuit is connected to the signal input terminal. The transmitting circuit is connected to the isolation channel. The signal receiving module includes a receiving circuit connected to the isolation channel. In the present invention, signal jitter is reduced, more stable signal transmission and a better isolation effect are achieved, and the area and cost of the digital isolator circuit are reduced.

Abstract: The present invention discloses a differential signal amplification circuit as well as a digital isolator and a digital receiver applying the differential signal amplification circuit, wherein the differential signal amplification circuit includes a multi-stage differential amplifier and a common-mode transient adaptive biasing circuit. The common-mode transient adaptive biasing circuit is configured to detect a positive or negative common-mode transient interference signal at a positive input terminal and a negative input terminal, and provide a biasing current of a differential amplifier of at least one stage above a second stage when the positive or negative common-mode transient interference signals are detected. With the technical solutions of the present invention, abnormal signal transmission caused by the common-mode interference signals can be suppressed.

Abstract: The present invention provides a common-mode transient suppression protection circuit for a digital isolator, including a modulation circuit, a demodulation circuit and an isolation capacitor connected between the modulation circuit and the demodulation circuit. The modulation circuit includes a modulation circuit front-end and a drive circuit, which are connected in sequence, and a clamping module is arranged in the drive circuit. The protection circuit further includes a linear voltage regulator structure connected with the drive circuit, and a power supply clamp is arranged in the linear voltage regulator structure. By providing the linear voltage regulator structure having the power supply clamp and the drive circuit having the clamping module in the protection circuit, low-voltage devices in the drive circuit can be protected from being damaged by high-voltage signals generated by common-mode transient interference.

Abstract: Provided are a low-jitter digital isolator circuit and a digital isolator including the same. The digital isolator circuit includes a signal transmitting module, a signal receiving module, and an isolation channel connected between the signal transmitting module and the signal receiving module. The signal transmitting module is provided with a signal input terminal, and the signal receiving module is provided with a signal output terminal. The signal transmitting module includes a reset circuit, an oscillator and a transmitting circuit which are sequentially connected. The reset circuit is connected to the signal input terminal. The transmitting circuit is connected to the isolation channel. The signal receiving module includes a receiving circuit connected to the isolation channel. In the present invention, more stable signal transmission and a better isolation effect are achieved, and the area and cost of the digital isolator circuit are reduced.

Abstract: Provided is a preamplifying circuit, including a first amplifier and a second amplifier sequentially connected in series, wherein an output end of the second amplifier is connected to a circuit output end, and an input end of the first amplifier is connected to a circuit input end. The preamplifying circuit further includes a positive feedback branch including a diode group and a third amplifier, wherein one end of the diode group is connected to the input end of the first amplifier. The positive feedback circuit can positively feed part of signals back to the other end of the diode group, so that voltage drops at two ends of the diode group can be reduced, and harmonic distortion caused by nonlinearity of the diode group is reduced. Thus, the sound quality detected by a microphone sensor is improved.