A counting element is dimensioned for sliding engagement along an outside surface of an elongated rod of an educational apparatus. The counting element includes an element body extending between first and second end surfaces. The element body includes an outer wall a plurality of inner walls disposed radially inward of the outer wall. The inner walls are operatively connected to the outer wall adjacent the first end surface and extend to a free end disposed toward the second end surface. The inner walls define a passage dimensioned to receive the elongated rod. The free ends of the inner wall portions are radially deflectable and function as biasing elements operative to generate frictional resistance to sliding movement of the counting element along the outside surface of the elongated rod. An educational apparatus includes a frame, a plurality of elongated rods and a plurality of counting elements. Methods are also included.

A counting element is dimensioned for sliding engagement along an outside surface of an elongated rod of an educational apparatus. The counting element includes an element body extending between first and second end surfaces. The element body includes an outer wall a plurality of inner walls disposed radially inward of the outer wall. The inner walls are operatively connected to the outer wall adjacent the first end surface and extend to a free end disposed toward the second end surface. The inner walls define a passage dimensioned to receive the elongated rod. The free ends of the inner wall portions are radially deflectable and function as biasing elements operative to generate frictional resistance to sliding movement of the counting element along the outside surface of the elongated rod. An educational apparatus includes a frame, a plurality of elongated rods and a plurality of counting elements. Methods are also included.

The invention is directed to an improved abacus and related calculating method. The improved abacus and method are adapted to perform mathematical operations including addition, subtraction, multiplication, division and factoring. Additional mathematical operations are performable using described techniques. The improved abacus has a frame divided into an upper and lower section by a horizontal bar. The abacus includes a plurality of rods in which each rod contains four movable beads on the upper section of each rod and one movable bead on the lower section of each rod. The beads in the upper section have a value of two and the bead in the lower section has a value of one. Beads moved toward the bar are counted while those beads away from the bar are not counted. The improved abacus also includes a unit indicator, mathematical operational signs and positive and negative sliding indicators signs on the frame.

The invention is directed to an improved abacus and related calculating method. The improved abacus and method are adapted to perform mathematical operations including addition, subtraction, multiplication, division and factoring. Additional mathematical operations are performable using described techniques. The improved abacus has a frame divided into an upper and lower section by a horizontal bar. The abacus includes a plurality of rods in which each rod contains four movable beads on the upper section of each rod and one movable bead on the lower section of each rod. The beads in the upper section have a value of two and the bead in the lower section has a value of one. Beads moved toward the bar are counted while those beads away from the bar are not counted. The improved abacus also includes a unit indicator, mathematical operational signs and positive and negative sliding indicators signs on the frame.

As disclosed herein a computer system for secure database backup and recovery in a secure database network has N distributed data nodes. The computer system includes program instructions that include instructions to receive a database backup file, fragment the file using a fragment engine, and associate each fragment with one node, where the fragment is not stored on the associated node. The program instructions further include instructions to encrypt each fragment using a first encryption key, and store, randomly, encrypted fragments on the distributed data nodes. The program instructions further include instructions to retrieve the encrypted fragments, decrypt the encrypted fragments using the first encryption key, re-encrypt the decrypted fragments using a different encryption key, and store, randomly, the re-encrypted fragments on the distributed data nodes. A computer program product and method corresponding to the above computer system are also disclosed herein.

As disclosed herein a computer system for secure database backup and recovery in a secure database network has N distributed data nodes. The computer system includes program instructions that include instructions to receive a database backup file, fragment the file using a fragment engine, and associate each fragment with one node, where the fragment is not stored on the associated node. The program instructions further include instructions to encrypt each fragment using a first encryption key, and store, randomly, encrypted fragments on the distributed data nodes. The program instructions further include instructions to retrieve the encrypted fragments, decrypt the encrypted fragments using the first encryption key, re-encrypt the decrypted fragments using a different encryption key, and store, randomly, the re-encrypted fragments on the distributed data nodes. A computer program product and method corresponding to the above computer system are also disclosed herein.

A manually operable calculating device is provided. The device includes a plurality of rods vertically disposed relative to one another. At least ten rings are slidably disposed on each of the plurality of rods. The at least ten rings include a first set of five rings including a first color and a second set of five rings including a second color. The plurality of rods each include a front surface opposite a rear surface. A plurality of numerals are disposed on the front surface and correspond to the number of rings. The rear surface is unnumbered.

A manually operable calculating device is provided. The device includes a plurality of rods vertically disposed relative to one another. At least ten rings are slidably disposed on each of the plurality of rods. The at least ten rings include a first set of five rings including a first color and a second set of five rings including a second color. The plurality of rods each include a front surface opposite a rear surface. A plurality of numerals are disposed on the front surface and correspond to the number of rings. The rear surface is unnumbered.

As disclosed herein a computer system for secure database backup and recovery in a secure database network has N distributed data nodes. The computer system includes program instructions that include instructions to receive a database backup file, fragment the file using a fragment engine, and associate each fragment with one node, where the fragment is not stored on the associated node. The program instructions further include instructions to encrypt each fragment using a first encryption key, and store, randomly, encrypted fragments on the distributed data nodes. The program instructions further include instructions to retrieve the encrypted fragments, decrypt the encrypted fragments using the first encryption key, re-encrypt the decrypted fragments using a different encryption key, and store, randomly, the re-encrypted fragments on the distributed data nodes. A computer program product and method corresponding to the above computer system are also disclosed herein.

The invention is directed to an improved abacus and related calculating method. The improved abacus and method are adapted to perform mathematical operations including addition, subtraction, multiplication, division and factoring. Additional mathematical operations are performable using described techniques. The improved abacus has a frame divided into an upper and lower section by a horizontal bar. The abacus includes a plurality of rods in which each rod contains four movable beads on the upper section of each rod and one movable bead on the lower section of each rod. The beads in the upper section have a value of two and the bead in the lower section has a value of one. Beads moved toward the bar are counted while those beads away from the bar are not counted. The improved abacus also includes a unit indicator, mathematical operational signs and positive and negative sliding indicators signs on the frame.