Abstract: Data is efficiently read from a sequence without a read position being revealed. A secure reading apparatus 1 receives a secret text sequence and a secret text of a read position as input, and outputs an element at the read position of the secret text sequence. A vector creating part (12) creates a vector expressing the read position. A compression computing part (13) repeatedly generates a new secret text sequence in which an inner product of a vector based on the secret text sequence and a vector expressing the read position is set as an element. The reading part (14) outputs the new secret text sequence having the number of elements of one as the element at the read position of the secret text sequence.

Abstract: A secret sharing value of a value represented by a “first target bit string” is used to obtain a secret sharing value of a value represented by a “first check bit string” obtained by setting a value of the most significant bit of the “first target bit string” to a value of a “first check bit” that is lower than the most significant bit. Here, the “first target bit string” corresponds to a null value when the most significant bit is 1 and corresponds to a real number when the most significant bit is 0. Next, the secret sharing value of the value represented by the “first check bit string” is used to obtain secret sharing values of bit values of the least significant bit to “first check bit” of the “first check bit string”.

Abstract: An inconsistency in shares is detected with a small volume of communications traffic. n inconsistency detecting devices generate random numbers si and make the random numbers si public. The n inconsistency detecting devices generate a common random number s which is the sum total of the random numbers s0, . . . , sn?1. The n inconsistency detecting devices calculate shares [c]i. The n inconsistency detecting devices generate shares [r]i, each of which would become a random number r by reconstruction. The n inconsistency detecting devices calculate shares [d]i, each of which would become a judgment value d by reconstruction. One inconsistency detecting device receives shares [d]1, . . . , [d]n?1 from n?1 inconsistency detecting devices. The one inconsistency detecting device restores n?k shares [d]?k, . . . , [d]?n?1 from k shares [d]0, . . . , [d]k?1. The one inconsistency detecting device judges, for j=k, . . . , n?1, whether or not a share [d]j and a share [d]?j coincide with each other.

Abstract: A combination of secure texts of values “a”, “b” and “c” having a relationship c=ab is efficiently generated. A secure text generation part 12 generates secure texts [xi] of xi satisfying xi=f(ki), and secure texts [yi] of yi satisfying yi=g(ki), for i=0, . . . , m. A fragment generation part 13 generates ?i decrypted from [xi]?[ai] and ?i decrypted from [yi]?[bi], for i=1, . . . , m, and calculates [ci]+?i[bi]+?i[ai]+?i?i and generates secure texts [z1], . . . , [zm]; and A random number synthesizing part 14 generates a secure text [z0] using different values k0, . . . , km and secure texts [z1], . . . , [zm].

Abstract: The present invention can be efficiently applied to secure computation and can achieve a low probability of successful tampering. A tampering detection device includes a parameter storage storing parameters ?ijk for uniformly mapping from two elements of a ring Rq to one element of the ring Rq, a division part 12 dividing N values a0, . . . , aN?1 into sets of q values to generate value vectors A0, . . . , A??1, a generation part 14 generating a checksum c, and a verification part 15 comparing a verification value generated by using the value vectors A0, . . . , A??1 with the checksum c to determine whether or not any of the values a0, . . . , aN?1 has been tampered with. Here, N and q are integers greater than or equal to 2 and ? is a minimum integer greater than or equal to N/q.

Abstract: A Fisher's exact test calculation apparatus includes: a condition storage 1 that has stored therein a condition for determining whether a result of Fisher's exact test corresponding to input is significant or not, the input being frequencies in a summary table; and a calculation unit 2 that obtains the result of Fisher's exact test corresponding to the frequencies in the summary table by inputting the frequencies in the summary table to the condition read from the condition storage 1.

Abstract: A vector generation unit generates a vector xn so that xn[i]?xn[j] if kn[i]=kn[j] at i?j. A set generation unit generates a set Bn,j so that individual elements correspond to combinations of the N?1 pieces of elements, which are individually selected from sets M0, . . . , MN?1 other than a set Mn, and xn[j] and the elements for all of the combinations are included. A matrix generation unit generates a matrix Tn? so that the matrix Tn? includes rows identical to Tn[j] in the number equal to the number of elements of the set Bn,j. A key generation unit generates a vector kn? so that elements of the matrix Tn? which correspond to a row identical to Tn[j] correspond to combinations of kn[j] and elements of the set Bn,j and further, the elements of the set Bn,j are different from each other when there are a plurality of rows identical to Tn[j].

Abstract: A secure computation technique of calculating a polynomial in a shorter calculation time is provided. A secure computation system includes: a comparing means 120 that generates concealed text [[u]] of u, which is the result of magnitude comparison between a value x and a random number r, from concealed text [[x]] by using concealed text [[r]]; a mask means 130 that generates concealed text [[c]] of a mask c from the concealed text [[x]], [[r]], and [[u]]; a reconstructing means 140 that reconstructs the mask c from the concealed text [[c]]; a coefficient calculating means 150 that calculates, for i=0, . . . , n, a coefficient bi from an order n, coefficients a0, a1, . . . , an, and the mask c; a selecting means 160 that generates, for i=1, . . . , n, concealed text [[si]] of a selected value si, which is determined in accordance with the result u of magnitude comparison, from the concealed text [[u]]; and a linear combination means 170 that calculates a linear combination b0+b1[[s1]]+ . . .

Abstract: A secure computation technique of calculating a power of 2 in a shorter calculation time is provided.

Abstract: Fisher's exact test is efficiently computed through secure computation. A computation range determination part 12 determines i0, i1, x0, x1. A preliminary computation part 13 computes f(x0), . . . , f(x1), and generates an array M=(f(x0), . . . , f(x1)). A securing part 14 secures the array M, and generates a secure text array <M>=(<f(x0)>, . . . , <f(x1)>). A batch-reading part 15 executes the following formulae, and generates a function value secure text (<f(ai)>, <f(bi)>, <f(ci)>, <f(di)>)(i0?i?i1). (<f(ai0)>,<f(ai0+1)>, . . . ,<f(ai1)>)?BatchRead(<M>;<a>;i0,i0+1, . . . ,i1), (<f(bi0)>,<f(bi0+1)>, . . . ,<f(bi1)>)?BatchRead(<M>;<b>;?i0,?(i0+1, . . . ,?i1), (<f(ci0)>,<f(ci0+1)>, . . . ,<f(ci1)>)?BatchRead(<M>;<c>;?i0,?(i0+1, . . . ,?i1), (<f(di0)>,<f(di0+1)>, . . . ,<f(di1)>)?BatchRead(<M>;<d>;i0,i0+1, . . .

Abstract: 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 <??1>, 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 <??1 >; a second column generating means 140 that generates, for j=a+1, . . .

Abstract: 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 (?, x, y) in which e[?] is bi,j[x] and e[?+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.

Abstract: Multiple elements are efficiently read from a secured array. A secure text array <a>=(<a[0]>, . . . , <a[n?1]>) where an array a=(a[0], . . . , a[n?1]) having a size of n is secured, secure text <x> of an integer x that is equal to or higher than 0 and less than n, and in integers i0, . . . , im-1 that are equal to or higher than 0 and less than n are input into an input part 11. A secure shift part 12 secure-shifts the secure text array <a> by <x> to obtain a secure text array <a?>=(<a?[0]>, . . . , <a?[n?1]>) where an array a?=(a?[0], . . . , a?[n?1]) obtained by shifting leftward the array a by x is secured. An array generation part 13 generates a secure text array <b>=(<a?[i0]>, . . . , <a?[im-1]>) from the secure text array <a?>.

Abstract: A Fisher's exact test calculation apparatus includes a selection unit that selects summary tables for which a result of Fisher's exact test indicative of being significant will be possibly obtained from among a plurality of summary tables based on a parameter obtained in calculation in course of determining the result of Fisher's exact test, and a calculation unit that performs calculations for Fisher's exact test for each of the selected summary tables.

Abstract: Fisher's exact test is efficiently computed through secure computation. It is assumed that a, b, c and d are frequencies of a 2×2 contingency table, [a], [b], [c] and [d] are secure texts of the respective frequencies a, b, c and d, and N is an upper bound satisfying a+b+c+d?N. A reference frequency computation part 12 computes a secure text ([a0], [b0], [c0], [d0]) of a combination of reference frequencies (a0, b0, c0, d0) which are integers satisfying a0+b0=a+b, c0+d0=c+d, a0+c0=a+c, and b0+d0=b+d. A number-of-patterns determination part 13 determines integers h0 and h1 satisfying h0?h1. A pattern computation part 14 computes [ai]=[a0]+i, [bi]=[b0]?i, [ci]=[c0]?i and [di]=[d0]+i for i=h0, . . . , h1, and obtains a set S={([ai], [bi], [ci], [di])}i of secure texts of combinations of frequencies (ai, bi, ci, di).

Abstract: 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 <p> of a pattern p, a secret text <c> of a vector c, and a secret text <E> of a matrix E and outputs a secret text <H> of a matrix H. A first matrix generating part 20 generates a secret text <F> 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 <F?> 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 <H[i][j]>=<F[i][j?i mod n+1]>?<c[i]>?¬<c[i?1]> to generate the secrete text <H>.

Abstract: A reactor includes a plurality of reaction side flow passages through which a reaction fluid flows, a catalyst (catalyst structure) disposed inside the reaction side flow passages to accelerate the reaction of the reaction fluid, a plurality of heat medium side flow passages which are alternately stacked with the reaction side flow passages, and through which a heat medium flows, and a suppression flow passage which is disposed adjacent to a surface of the reaction side flow passage, the heat medium side flow passages being not stacked on the surface, and through which flows a suppression fluid suppressing the heat dissipation to the outside from the reaction fluid flowing through the reaction side flow passage, or the heat transfer from the outside to the reaction fluid.

Abstract: A concealed-decision-tree computation system includes a user apparatus and 0th to (n?1)-th server apparatuses, where n is a predetermined positive integer. The user apparatus secret-shares data D into n shares [D]j (j=0, . . . , n?1) and sends the n shares [D]j (j=0, . . . , n?1) to the 0th to (n?1)-th server apparatuses, respectively. The 0th to (n?1)-th server apparatuses use the n shares [D]j (j=0, n?1) to perform secret cooperation computation to obtain n shares [out]0, . . . , [out]n-1 of a value “out” corresponding to the data D in a predetermined decision tree and send the n shares [out]0, . . . , [out]n-1 to the user apparatus. The user apparatus uses at least k shares out of the n received shares [out]0, . . . , [out]n-1 to restore the value “out” corresponding to the data D in the predetermined decision tree, where k is a predetermined integer equal to or smaller than n.

Abstract: Provided is a reactor in which a catalyst to accelerate reaction of a reactant is allowed to act on a reaction fluid having the reactant. The reactor has a partition that defines, in a parallel form, a plurality of reaction flow passages through which the reaction fluid flows, and a plurality of catalyst structures, each having a catalyst and being respectively provided in each of the plurality of reaction flow passages. The partition has a communicating portion allowing the plurality of reaction flow passages to communicate mutually.

Abstract: A secure text having an authentication code is efficiently created. A key generation part 12 generates secure texts ([x], [?], [?]) of “x”, “?” and “?” that are values satisfying x?=?. A secure text generation part 13 generates secure texts [ai] of random values “ai” for i=1, . . . , N. An authentication code generation part 14 generates authentication codes [?(ai)] by multiplying the secure texts [ai] by the secure text [?] for i=1, . . . , N. A verification value generation part 15 generates a secure text [w] of a verification value “w” using the secure texts ([x], [?], [?]), the secure text [ai] and the authentication code [?(ai)]. A verification value determination part 16 determines whether the verification value “w” is equal to zero or not.