Nondecreasing sequence determining device, method and program

    公开(公告)号:US10333697B2

    公开(公告)日:2019-06-25

    申请号:US15516175

    申请日:2015-10-05

    摘要: Determination as to whether a nondecreasing sequence exists or not is efficiently made. A sorting part sorts elements of a set Pi in ascending order to generate vectors ti,i+1 and bi,i+1. A merging part generates vectors t0,m and b0,m by repeating the process of merging vectors (ti,j, bi,j) and (tj,k, bj,k) to generate (ti,k, bi,k). A stable-sorting part generates a vector e by coupling and stably sorting vectors bi,j and tj,k. A searching part searches for sets of (λ, x, y) in which e[λ] is bi,j[x] and e[λ+1] is tj,k[y] and generates a set X including all x and a set Y including all y. An extracting part sorts ti,j[x] (x∈X) in ascending order to generate a vector ti,k and sorts bj,k[y] (y∈Y) in ascending order to generate a vector bi,k. If the length of a vector t0,m is 0, a determining part outputs a result of determination that indicates the absence of a nondecreasing sequence.

    Secure joining system, method, secure computing apparatus and program

    公开(公告)号:US11888973B2

    公开(公告)日:2024-01-30

    申请号:US17267837

    申请日:2019-08-08

    摘要: A secure joining system is a secure joining system including a plurality of secure computing apparatuses. The plurality of secure computing apparatuses include a first vector joining unit, a first permutation calculation unit, a first vector generation unit, a second vector joining unit, a first permutation application unit, a second vector generation unit, a first inverse permutation application unit, a first vector extraction unit, a second permutation application unit, a third vector generation unit, a second inverse permutation application unit, a second vector extraction unit, a modified second table generation unit, a third permutation application unit, a fourth vector generation unit, a shifting unit, a third inverse permutation application unit, a bit inversion unit, a third vector extraction unit, a modified first table generation unit, a first table joining unit, and a first table formatting unit.

    Secure equijoin system, secure equijoin device, secure equijoin method, and program

    公开(公告)号:US11250004B2

    公开(公告)日:2022-02-15

    申请号:US16330212

    申请日:2017-09-14

    摘要: A secure equijoin technique of generating one table from two tables while curbing the volume of communications traffic is provided. The technique includes: a first permutation generating means 110 that generates a permutation from an element sequence which is generated from the first column of a table L and the first column of a table R; a first column generating means 120 that generates, for j=2, . . . , a, by using the permutation , a prefix sum, and an inverse permutation , the j-th column of a table J from an element sequence which is generated from the to j-th column of the table L; a join-result element sequence generating means 130 that generates a join-result element sequence from an element sequence ([[1]], . . . , [[1]], [[0]], . . . , [[0]], [[−1]], . . . , [[−1]]) by using the permutation , the prefix sum, and the inverse permutation ; a second column generating means 140 that generates, for j=a+1, . . . , a+b−1, the j-th column of the table J by using the join-result element sequence and the j−a+1-th column of the table R; and a third column generating means 150 that generates the first column of the table J by using the join-result element sequence and the first column of the table R.

    Database system and database processing method

    公开(公告)号:US10579813B2

    公开(公告)日:2020-03-03

    申请号:US15570445

    申请日:2016-05-06

    摘要: A database system comprises a determining part 13 determining whether or not to conceal information to be registered in a database, a terminal device 1 that, if the determining part 13 determines that the information is to be concealed, generates N information fragments by secret-sharing the information and sends the N information fragments to a system management device 2, where N is a predetermined positive integer, the system management device 2 sending the N information fragments received from the terminal device 1 to N different database devices 3, and N database devices 3 each storing one of N information fragments received from the system management device 2.

    Device, method and program for detecting positions of partial character strings

    公开(公告)号:US10291396B2

    公开(公告)日:2019-05-14

    申请号:US15515650

    申请日:2015-10-05

    摘要: The positions in a text in which partial character strings in a pattern appear are efficiently detected. A partial-character-string position detecting device 1 takes inputs of a secret text [t] of a text t, a secrete text of a pattern p, a secret text of a vector c, and a secret text of a matrix E and outputs a secret text of a matrix H. A first matrix generating part 20 generates a secret text of a matrix F, in which F[i][j]=E[i][j+i mod n+1] (where it is assumed that E[i][n]=¬c[i]). A second matrix generating part 30 generates a secret text of a matrix F′, in which F[i][j]=1 is set if c[i]=0 or if c[i]=1 and F[k][j]=1 for every k that is successively c[k]=1, otherwise F[i][j]=0 is set, where k=i, . . . , n−1. A third matrix generating part 40 computes = ∧ ∧¬ to generate the secrete text .