Abstract: In a metal negative cell in which the negative electrode mainly comprises a metal such as aluminum, magnesium, zinc, lithium, etc., self discharge readily occurs when the negative electrode and an electrolytic solution are in contact, and the problem of large capacity loss of the cell readily occurs. The metal negative cell is provided with a metal negative cell in which the self-discharge amount is reduced, and the capacity loss of the cell is reduced during use or storage, whereby the metal negative cell varies the cell output according to demand.

Abstract: In a metal negative cell in which the negative electrode mainly comprises a metal such as aluminum, magnesium, zinc, lithium, etc., self discharge readily occurs when the negative electrode and an electrolytic solution are in contact, and the problem of large capacity loss of the cell readily occurs. The metal negative cell is provided with a metal negative cell in which the self-discharge amount is reduced, and the capacity loss of the cell is reduced during use or storage, whereby the metal negative cell varies the cell output according to demand.

Abstract: A file editing system that provides a high file content secrecy, a file version management and an asynchronous editing is disclosed. For a high file content secrecy, the block data of files managed by a file management server device are enciphered in units of blocks, and a client device obtains the block data of the desired file in enciphered state, deciphers the obtained block data in units of blocks, carries out an editing of the desired file to obtain editing data, enciphers the editing data in units of blocks, and transmits the enciphered editing data to the file management server device.

Abstract: A file editing system that provides a high file content secrecy, a file version management and an asynchronous editing is disclosed. For a high file content secrecy, the block data of files managed by the a file management server device are enciphered in units of blocks, and the a client device obtains the block data of the desired file in enciphered state, deciphers the obtained block data in units of blocks, carries out an editing of the desired file to obtain editing data, enciphers the editing data in units of blocks, and transmits the enciphered editing data to the file management server device.

Abstract: A file editing system that provides a high file content secrecy, a file version management and an asynchronous editing is disclosed. For a high file content secrecy, the block data of files managed by a file management server device are enciphered in units of blocks, and a client device obtains the block data of the desired file in enciphered state, deciphers the obtained block data in units of blocks, carries out an editing of the desired file to obtain editing data, enciphers the editing data in units of blocks, and transmits the enciphered editing data to the file management server device.

Abstract: A scheme for encrypting and transferring electronic mails which enables the realization of the information management regarding encrypted electronic mails by an electronic mail manager, and the transfer control regarding encrypted electronic mails. A management encryption key information is produced by encrypting the message encrypting key according to a public-key cryptography by using a prescribed management public key, in addition to the usual sender's encryption key information and each receiver's encryption key information. The encrypted electronic mail is then constructed from the encrypted message, the sender's encryption key information, each receiver's encryption key information and the management encryption key information. At a time of transferring the electronic mail, whether this electronic mail is an encrypted electronic mail or not is identified and whether a transfer of this electronic mail is permitted or not is judged according an identification result.

Abstract: A file editing system that provides a high file content secrecy, a file version management, and an asynchronous editing is disclosed. For a high file content secrecy, the block data of files managed by a file management server device are enciphered in units of blocks, and a client device obtains the block data of the desired file in enciphered state, deciphers the obtained block data in units of blocks, carries out an editing of the desired file to obtain editing data, enciphers the editing data in units of blocks, and transmits the enciphered editing data to the file management server device.