Abstract: Provided are an electrolyte solution for a redox flow battery including an organic active material having improved solubility and potential and a redox flow battery using the same.

Abstract: A method for preparing a positive electrode active material precursor includes preparing a metal aqueous solution including a nickel raw material, a cobalt raw material, and a manganese raw material (step 1); adding the metal aqueous solution, an ammonium cation complex forming agent, and a basic aqueous solution into a reactor, co-precipitating the mixture at pH 11 to less than pH 12 to form nuclei of first positive electrode active material precursor particles and growing the nuclei (step 2); adjusting input amount of the basic aqueous solution to increase the pH in the reactor to a range of 0.8 to 1.5 compared to that of step 2; and adjusting input amount of the basic aqueous solution to change the pH in the reactor to pH 11 to less than pH 12 (step 4). A positive electrode active material precursor prepared by the above preparation method has an improved packing density.

Abstract: Disclosed is an apparatus for protecting a copyright of a 3D object model and method therefor, the apparatus including: a first module generating an original 3D object model by combining voxels in a 3D space of X, Y, and Z axes; a second module calculating voxel lengths of the axes and based on a voxel length of a longest axis among the lengths, the second module extending lengths of the remaining axes, thereby obtaining a 3D space area; a third module generating an obfuscation unique key; a fourth module generating at least one rotation axis position, rotation voxel range, and rotation frequency based on the key; and a fifth module axially rotating at least one voxel structure included in each rotation voxel range at a rotation angle by each rotation frequency to distort a shape of the model, thereby performing obfuscation. Accordingly, the copyright can be effectively protected.