Abstract: A preparation method of a hemostatic material is provided, wherein the method mainly includes mixing a keratin and an alginate; obtaining a keratin-alginate composite scaffold by a freeze-gelation method; and drying the keratin-alginate composite scaffold to obtain a hemostatic material. Further, a methylene blue can be loaded into the hemostatic material so that the hemostatic material has antimicrobial photodynamic abilities.

Abstract: A code rate adaptive encoding/decoding arrangement and method for a pulse code modulation system comprises a code rate adaptor and a code capacity meter to dynamically produce a code rate adaptive signal for the code length of the pulse code modulation adaptive to actual situations during the encoding/decoding process.

Abstract: A code rate adaptive encoding/decoding arrangement and method for a pulse code modulation system comprises a code rate adaptor and a code capacity meter to dynamically produce a code rate adaptive signal for the code length of the pulse code modulation adaptive to actual situations during the encoding/decoding process.

Abstract: A digital tone mixer includes a first digital volume regulator electrically connected to a first tone generator and having a binary signal output corresponding to the desired amplitude of a pulsating tone signal from the first tone generator; a second digital volume regulator electrically connected to a second tone generator and having a binary signal output corresponding to the desired amplitude of a pulsating tone signal from the second tone generator; a binary adder for summing the binary signal outputs of the first and second volume regulators; and a pulse rate modulator receiving a binary output from the binary adder and generating a pulse train which has a pulse density corresponding to the binary output of the binary adder. The digital tone mixer has a very stable output characteristic.