This paper introduces atomic proxy cryptography, in which an atomic proxy function, in conjunction with a public proxy key, converts ciphertext (messages in a public key encryption scheme or signatures in a digital signature scheme) for one key (k 1) into ciphertext for another (k 2). Proxy keys, once generated, may be made public and proxy functions applied in untrusted environments. Various k...

A proxy signature scheme enables an entity to delegate its signing rights to another entity. Since the proxy signature concept was proposed by Mambo et al., many variant schemes have been appeared. In this paper, we propose a new proxy signature scheme with a proxy signer's privacy protection. In proxy signer's privacy scenario, the identity of the proxy signer cannot be revealed in a proxy sig...

In the (t, n) proxy signature scheme, the signature, originally signed by a signer, can be signed by t or more proxy signers out of a proxy group of n members. Recently, an efficient nonrepudiable threshold proxy signature scheme with known signers was proposed by H.-M. Sun. Sun’s scheme has two advantages. One is nonrepudiation. The proxy group cannot deny that having signed the proxy signatur...

A proxy signature allows a designated person, called a proxy signer, to sign the message on behalf of the original signer. Proxy signatures are very useful tools when one needs to delegate his/her signing capability to other party. A number of proxy signature schemes have been proposed and succeeded for proxy delegations, but the schemes are in defective in proxy revocations. In this paper, we ...

Abstract A (t, n) threshold proxy signature scheme enables an original signer to delegate the signature authority to a proxy group of n member such that t or more than t proxy signers can cooperatively sign messages on behalf of the original signer. In the paper, we review the security of some nonrepudiable threshold proxy signature schemes with known signers. We show that Sun’s threshold proxy...

In a ðt; nÞ threshold proxy signature scheme, the original signer delegates the power of signing messages to a designated proxy group of n members. Any t or more proxy signers of the group can cooperatively issue a proxy signature on behalf of the original signer, but ðtÿ 1Þ or less proxy signers cannot. Previously, all of the proposed threshold proxy signature schemes have been based on the di...

In a ) , ( n t threshold proxy signature scheme, one original signer delegates a group of n proxy signers to sign messages on behalf of the original signer. When the proxy signature is created, at least t proxy signers cooperate to generate valid proxy signatures and any less than t proxy signers can’t cooperatively generate valid proxy signatures. So far, all of proposed threshold proxy signat...

this report presents a 52-year-old woman who was admitted to nephrology ward with hypernatremia. she shared a persecutory delusion of poisoning with her 22-year-old daughter and did not feed her 8-year-old son due to her delusion. keywords: shared paranoid disorder, delusions, schizophrenia, paranoid.

An identity-based multi-proxy signature is a type of proxy signatures in which the delegation of signing right is distributed among a number of proxy signers. In this type of cryptographic primitive, cooperation of all proxy signers in the proxy group generates the proxy signatures of roughly the same size as that of standard proxy signatures on behalf of the original signer, which is more effi...

the present study considered the situation of kilka stocks in last decades by using overfished biomass threshold, fishing effort ratio and fishing mortality proxy during 1991-2010. the cpue index of anchovy and mixed-species of kilka indicated an undepleted from 1991 to 2000. in 2000, the cpue ratio declined to close to the “in danger” region, and subsequently collapsed to “overfished” region f...