Abstract: The present disclosure belongs to the field of estimators, and provides a generalized estimator (GE), and a generalized disturbance rejection controller (GDRC) and a design method thereof. The GE includes an inner-loop estimation controller and a nominal model module of a controlled object. The inner-loop estimation controller transmits a control signal to the nominal model module. The nominal model module includes a nominal model of the controlled object. The GE is structurally uniform, and functionally interchangeable. With the structure of the GE, the typical disturbance rejection controller (DRC) is unified to a same control framework to obtain the GDRC that is more universal. The GDRC can design different control strategies according to existing conditions of most systems.

Abstract: The present disclosure provides a weakly-confined semiconductor nanocrystal, a preparation method therefor and use thereof. A size of the nanocrystals is larger than an exciton diameter thereof; excitons in the nanocrystal are dynamic excitons, electron-hole Coulomb interaction of the dynamic excitons is insufficient to bind electrons and holes into stable bound excitons at operating temperatures, and the electrons and the holes of the dynamic excitons are constrained by boundaries of the nanocrystal. Since the excitons in the weakly-confined nanocrystals herein possess the characteristics of dynamic excitons, the nanocrystals herein possess unique optical and photoelectric properties distinct from conventional semiconductor nanomaterials. It holds unique value for applications requiring broad-spectrum emission (such as lighting) and significant importance for photovoltaic solar devices, photoelectric detectors, and photocatalysis.

Abstract: The present invention relates to a preparation and purification method for cationic quaternary ammonium salt of sodium hyaluronate in homogeneous medium. By adding a homogeneous solvent and a sodium hyaluronate solid to a vessel, heating the vessel until the contents are dissolved to form a homogeneous system, adding an aqueous solution of 2,3-epoxypropyltrimethylammonium chloride (GTA) to the homogeneous system, then adding a base catalyst, and stirring at a preset temperature to carry out a graft reaction, a graft product is obtained wherein 2,3-epoxypropyltrimethylammonium chloride is grafted to the oxygen atom of the hydroxymethyl group of sodium hyaluronate. By using the method, a graft product wherein 2,3-epoxypropyltrimethylammonium chloride is grafted to the oxygen atom of the hydroxymethyl group of sodium hyaluronate is obtained. Addition of salts is avoided during the reaction, a grafting yield up to 0.69 is obtained, and coagulation occurred to the product is effectively solved.

Abstract: One embodiment provides a system for measuring optical fiber channel loss in photonic communication. During operation, a first multiplexing device receives a first signal which is a photonic signal and a second signal which is a reference light signal transmitted by a first measuring device. In response, the first multiplexing device couples the first signal with the second signal, and transmits the coupled signal via an optical fiber channel to a second multiplexing device. The second multiplexing device separates the coupled signal into a separated first signal and a separated second signal, and transmits the separated second signal to a second measuring device. The system obtains indices related to a degree of loss of the optical fiber channel based on the separated second signal.

Abstract: One embodiment provides a system for measuring optical fiber channel loss in photonic communication. During operation, a first multiplexing device receives a first signal which is a photonic signal and a second signal which is a reference light signal transmitted by a first measuring device. In response, the first multiplexing device couples the first signal with the second signal, and transmits the coupled signal via an optical fiber channel to a second multiplexing device. The second multiplexing device separates the coupled signal into a separated first signal and a separated second signal, and transmits the separated second signal to a second measuring device. The system obtains indices related to a degree of loss of the optical fiber channel based on the separated second signal.

Abstract: One embodiment provides a system for measuring optical fiber channel loss in photonic communication. During operation, a first multiplexing device receives a first signal which is a photonic signal and a second signal which is a reference light signal transmitted by a first measuring device. In response, the first multiplexing device couples the first signal with the second signal, and transmits the coupled signal via an optical fiber channel to a second multiplexing device. The second multiplexing device separates the coupled signal into a separated first signal and a separated second signal, and transmits the separated second signal to a second measuring device. The system obtains indices related to a degree of loss of the optical fiber channel based on the separated second signal.

Abstract: Embodiments of the present application provide apparatus and methods for generating a shared key, including setting up a key negotiation connection, and determining an algorithm code by negotiating using the key negotiation connection. An algorithm corresponding to the algorithm code is retrieved from a pre-stored algorithm library, and a pre-stored seed key is calculated using the algorithm to obtain a shared key. Compared with traditional key generation methods, embodiments of the present invention avoid the problem of a high bit error rate that occurs in the traditional quantum key generation methods, especially quantum key generation methods. One exemplary method determines an algorithm code through negotiation, retrieves a pre-stored algorithm corresponding to the algorithm code, and generates a new shared key using a seed key.

Abstract: One embodiment provides a system for measuring optical fiber channel loss in photonic communication. During operation, a first multiplexing device receives a first signal which is a photonic signal and a second signal which is a reference light signal transmitted by a first measuring device. In response, the first multiplexing device couples the first signal with the second signal, and transmits the coupled signal via an optical fiber channel to a second multiplexing device. The second multiplexing device separates the coupled signal into a separated first signal and a separated second signal, and transmits the separated second signal to a second measuring device. The system obtains indices related to a degree of loss of the optical fiber channel based on the separated second signal.

Abstract: Embodiments of the present application provide apparatus and methods for generating a shared key, including setting up a key negotiation connection, and determining an algorithm code by negotiating using the key negotiation connection. An algorithm corresponding to the algorithm code is retrieved from a pre-stored algorithm library, and a pre-stored seed key is calculated using the algorithm to obtain a shared key. Compared with traditional key generation methods, embodiments of the present invention avoid the problem of a high bit error rate that occurs in the traditional quantum key generation methods, especially quantum key generation methods. One exemplary method determines an algorithm code through negotiation, retrieves a pre-stored algorithm corresponding to the algorithm code, and generates a new shared key using a seed key.