Patent ID: 11961648
Assignee: BEIJING UNIVERSITY OF TECHNOLOGY
Field: Measurement (Instruments)
Classification: CPC G  H | IPC G  H

Claim 1:
2. The rapid demagnetization method of claim 1, wherein an input of the magnetic medium recognition module is the magnetic medium to be demagnetized, defined as X; an output of the magnetic medium recognition module is the characteristic information of the magnetic medium to be demagnetized, defined as {ρrecord, ηmaterial, ζforce, . . . }; and the magnetic medium recognition module is operated through steps of:
designing a basic structure of a magnetic medium recognition database, shown as equation (1):

[{Plant,SN},{Capicity,Revolution,ProTime, . . . },{ρrecord,ηmaterial,ζforce, . . . }]  (1);

 wherein {Plant,SN} represents a complete identification code consisting of manufacturer and serial number; and {Capicity,Revolution, ProTime, . . . }, represents a basic information consisting of capacity, revolution and production time of a magnetic medium;
designing a basic structure of a magnetic medium characteristic database, shown as equation (2)

[{Plant,SN},{ρrecord,ηmateria,ζforce, . . . },{Hopersp,αopersp, . . . }]  (2); and

performing the following steps for the magnetic medium to be demagnetized X:
scanning, by a bar code scanner in a bar code scanning module, a bar code {Xcode, . . . } of X based on an optical device to obtain an optical signal, wherein the bar code {Xcode, . . . } comprises an SN code; converting the optical signal into an electrical signal, and then into a digital signal; and processing the digital signal according to a decoding algorithm in a bar code processing module to obtain a number or letter symbol {X′SN, . . . } representing an SN code and corresponding to the bar code of X, expressed by equation (3):, X
      
       →
       
        
         f
         scan
        
        (
        ·
        )
       
      
      
       
        {
        
         
          X
          code
         
         ,
         …
        
           
        }
       
       
        →
        
         
          f
          decode
         
         (
         ·
         )
        
       
       
        {
        
         
          X
          SN
          ′
         
         ,
         …
        
           
        }
       
      
     
     ;
    
   
   
    
     (
     3
     )
    
   
  
 

 wherein fscan(·) represents a process of scanning the bar code of X; and fdecode(·) represents a process of decoding the bar code;
collecting and acquiring, by a camera device in an image acquisition module, an image of the magnetic medium to be demagnetized X; and extracting a basic information {X′Plant, . . . } comprising manufacturer, capacity, revolution and production time of the magnetic medium to be demagnetized according to an image recognition algorithm in an image processing module, expressed as equation (4):, X
      
       →
       
        
         f
         camera
        
        (
        ·
        )
       
      
      
       {
       
        
         X
         image
        
        ,
        …
       
          
       }
      
      
       →
       
        
         f
         image
         iden
        
        (
        ·
        )
       
      
      
       {
       
        
         X
         Plant
         ′
        
        ,
        …
       
          
       }
      
     
     ;
    
   
   
    
     (
     4
     )
    
   
  
 

wherein fcamera(·) represents a process of acquiring the image of X; and fimageiden(·) represents the image recognition algorithm for identifying the basic information {X′Plant, . . . } of X;
if it is capable of obtaining the complete identification code {Plant,SN} from the magnetic medium recognition database by matching through fusion of {X′SN, . . . } and {X′Plant, . . . } in a magnetic medium basic information recognition sub-module, completing the recognition of the magnetic medium to be demagnetized; and extracting the characteristic information {ρrecord, ηmaterial, ζforce, . . . } comprising the magnetic recording mode, material characteristic, and coercive force from the magnetic medium characteristic database; and
if it fails to obtain the complete identification code {Plant,SN} from the magnetic medium recognition database by matching through the fusion of {X′SN, . . . } and, {X′Plant, . . . } performing similarity matching in a magnetic medium characteristic database in a magnetic medium characteristic information extraction sub-module according to the basic information {Capicity,Revolution, ProTime, . . . }, obtained from {X′SN, . . . } and {X′Plant, . . . }; and acquiring the characteristic information {ρrecord, ηmaterial, ζforce, . . . } of the magnetic medium to be demagnetized, as shown in equation (5):, {
       
        Capicity
        ,
        Revolution
        ,
        ProTime
        ,
        …
       
          
       }
      
      
       →
       
        
         f
         match
         iden
        
        (
        ·
        )
       
      
      
       {
       
        
         ρ
         record
        
        ,
        
         η
         material
        
        ,
        
         ζ
         force
        
        ,
        …
       
          
       }
      
     
     ;
    
   
   
    
     (
     5
     )
    
   
  
 

 wherein fmatchiden(·) is a matching model based on a case-based reasoning algorithm.