Abstract: A synchronous rectification control system and method for a quasi-resonant flyback converter are provided. The control system includes a switching transistor voltage sampling circuit configured to sample an output terminal voltage of the switching transistor to obtain a sampled voltage of the switching transistor; a sampling calculation module configured to obtain a dead-time based on the sampled voltage of the switching transistor and a preset relationship, the preset relationship being a correspondence between the duration of the sampled voltage of the switching transistor being below a first preset value and the dead-time during an on-time of a switching cycle of the switching transistor, the dead-time being a time from when the switching transistor is turned off to when the synchronous rectification transistor is turned on; and a control module configured to receive the dead-time and control switching of the synchronous rectification transistor based on the dead-time.

Abstract: A synchronous rectification control system and method for a quasi-resonant flyback converter are provided. The control system includes a switching transistor voltage sampling circuit configured to sample an output terminal voltage of the switching transistor to obtain a sampled voltage of the switching transistor; a sampling calculation module configured to obtain a dead-time based on the sampled voltage of the switching transistor and a preset relationship, the preset relationship being a correspondence between the duration of the sampled voltage of the switching transistor being below a first preset value and the dead-time during an on-time of a switching cycle of the switching transistor, the dead-time being a time from when the switching transistor is turned off to when the synchronous rectification transistor is turned on; and a control module configured to receive the dead-time and control switching of the synchronous rectification transistor based on the dead-time.

Abstract: The present invention discloses a near-infrared regenerative intelligent fiber-based adsorptive material and a preparation method and use thereof. The material is obtained by chemically grafting a stepwise dual-temperature stimuli-responsive polyethyleneimine onto a carboxylated cellulose nanofiber matrix to prepare a stepwise dual-temperature stimuli-responsive intelligent nanofiber, and combining the stepwise dual-temperature stimuli-responsive intelligent nanofiber with a photosensitizer having near-infrared stimuli-response to prepare a stepwise dual-temperature/near-infrared stimuli-responsive intelligent nanofiber, and then by using a crosslinking agent to directly crosslink and combine the stepwise dual-temperature/near-infrared stimuli-responsive intelligent nanofiber with a hyperbranched polyamine in one step. The material has a stepwise dual-temperature/near-infrared stimuli-response, high density of amino group (greater than 14 mmol/g), and nano cavities.

Abstract: A computer controlled display system for automatically generating quality assurance contract requirements. The quality level of each of a set of quality attributes of a software supplier is assessed, and at least one contract requirement for each of said quality attributes for said supplier is generated based upon the quality level of said attribute. The assessment of the quality level preferably involves determining one of a plurality of quality levels for each of said set of quality attributes, and generating a different contract requirement for each of said quality levels for each attribute. The set of quality attributes may consist of a single overall quality characteristic having several predetermined quality levels. In such a case, there is generated a plurality of contract requirements for each of said predetermined quality levels.