Certificateless public key cryptography is a new paradigm introduced by Al-Riyami and Paterson.It eliminates the need of the certificates in traditional public key cryptosystems and the key escrow problem in IDentity-...Certificateless public key cryptography is a new paradigm introduced by Al-Riyami and Paterson.It eliminates the need of the certificates in traditional public key cryptosystems and the key escrow problem in IDentity-based Public Key Cryptography(ID-PKC).Due to the advantages of the certificateless public key cryptography,a new efficient certificateless pairing-based signature scheme is presented,which has some advantages over previous constructions in computational cost.Based on this new signature scheme,a certificateless blind signature scheme is proposed.The security of our schemes is proven based on the hardness of computational Diffie-Hellman problem.展开更多
AIM. To assess the causes of ileocecal mass in patients with amebic liver abscess. METHODS: Patients with amebic liver abscess and ileocecal mass were carefully examined and investigated by contrast-enhanced CT scan ...AIM. To assess the causes of ileocecal mass in patients with amebic liver abscess. METHODS: Patients with amebic liver abscess and ileocecal mass were carefully examined and investigated by contrast-enhanced CT scan followed by colonoscopy and histological examination of biopsy materials from lesions during colonoscopy. RESULTS: Ileocecal masses were found in seventeen patients with amebic liver abscess. The cause of the mass was ameboma in 14 patients, cecal tuberculosis in 2 patients and adenocarcinoma of the cecum in 1 patient. Colonic ulcers were noted in five of the six (83%) patients with active diarrhea at presentation. The ileocecal mass in all these patients was ameboma. Ulcers were seen in only one of the 11 (9%) patients without diarrhea. The difference was statistically significant from the group with diarrhea (P〈 0.005). CONCLUSION: Ileocecal mass is not an uncommon finding in patients with amebic liver abscess. Although, the ileocecal mass is due to ameboma formation in most cases, it should not be assumed that this is the case in all patients. Colonoscopy and histological examination of the target biopsies are mandatory to avoid missing a more sinister lesion.展开更多
Lode 28 is the largest gold-bearing quartz vein in Haigou gold deposit, and the lode itself contains more than 301 of gold. Geochemical study shows that 12 trace elements related gold mineralization can be divided int...Lode 28 is the largest gold-bearing quartz vein in Haigou gold deposit, and the lode itself contains more than 301 of gold. Geochemical study shows that 12 trace elements related gold mineralization can be divided into 5 metallogenic factors (element assemblages). The high values of F1 , F2 and F4 together indicate overlapped of multiple stages of gold mineralization, revealing high potential of gold mineralization at depth ; the single high value of F4 represents the root of an existing ore body while high values of F3 and F4 show the intervals of barton sectors in the lode. Comprehensive geochemical studies show the high prospeetion potential below the 14^th level and between lines 39-71. It is also prospective to look for blind ore-bodies between lines 15-29 and below the 10^th level.展开更多
An iterative separation approach, i.e. source signals are extracted and removed one by one, is proposed for multichannel blind deconvolution of colored signals. Each source signal is extracted in two stages: a filtere...An iterative separation approach, i.e. source signals are extracted and removed one by one, is proposed for multichannel blind deconvolution of colored signals. Each source signal is extracted in two stages: a filtered version of the source signal is first obtained by solving the generalized eigenvalue problem, which is then followed by a single channel blind deconvolution based on ensemble learning. Simulation demonstrates the capability of the approach to perform efficient mutichannel blind deconvolution.展开更多
基金the National Natural Science Foundation of China (No.60673070)the Natural Science Foundation of Jiangsu Province (No.BK2006217)the Open Project of the Key Lab. on Computer Networks and Information Security (Xidian University) of Ministry of Education of China(No.20040105)
文摘Certificateless public key cryptography is a new paradigm introduced by Al-Riyami and Paterson.It eliminates the need of the certificates in traditional public key cryptosystems and the key escrow problem in IDentity-based Public Key Cryptography(ID-PKC).Due to the advantages of the certificateless public key cryptography,a new efficient certificateless pairing-based signature scheme is presented,which has some advantages over previous constructions in computational cost.Based on this new signature scheme,a certificateless blind signature scheme is proposed.The security of our schemes is proven based on the hardness of computational Diffie-Hellman problem.
文摘AIM. To assess the causes of ileocecal mass in patients with amebic liver abscess. METHODS: Patients with amebic liver abscess and ileocecal mass were carefully examined and investigated by contrast-enhanced CT scan followed by colonoscopy and histological examination of biopsy materials from lesions during colonoscopy. RESULTS: Ileocecal masses were found in seventeen patients with amebic liver abscess. The cause of the mass was ameboma in 14 patients, cecal tuberculosis in 2 patients and adenocarcinoma of the cecum in 1 patient. Colonic ulcers were noted in five of the six (83%) patients with active diarrhea at presentation. The ileocecal mass in all these patients was ameboma. Ulcers were seen in only one of the 11 (9%) patients without diarrhea. The difference was statistically significant from the group with diarrhea (P〈 0.005). CONCLUSION: Ileocecal mass is not an uncommon finding in patients with amebic liver abscess. Although, the ileocecal mass is due to ameboma formation in most cases, it should not be assumed that this is the case in all patients. Colonoscopy and histological examination of the target biopsies are mandatory to avoid missing a more sinister lesion.
文摘Lode 28 is the largest gold-bearing quartz vein in Haigou gold deposit, and the lode itself contains more than 301 of gold. Geochemical study shows that 12 trace elements related gold mineralization can be divided into 5 metallogenic factors (element assemblages). The high values of F1 , F2 and F4 together indicate overlapped of multiple stages of gold mineralization, revealing high potential of gold mineralization at depth ; the single high value of F4 represents the root of an existing ore body while high values of F3 and F4 show the intervals of barton sectors in the lode. Comprehensive geochemical studies show the high prospeetion potential below the 14^th level and between lines 39-71. It is also prospective to look for blind ore-bodies between lines 15-29 and below the 10^th level.
基金Supported by the National Natural Science Foundation of China(No.60072048)the Doctoral Program Fund(No.20010561007)
文摘An iterative separation approach, i.e. source signals are extracted and removed one by one, is proposed for multichannel blind deconvolution of colored signals. Each source signal is extracted in two stages: a filtered version of the source signal is first obtained by solving the generalized eigenvalue problem, which is then followed by a single channel blind deconvolution based on ensemble learning. Simulation demonstrates the capability of the approach to perform efficient mutichannel blind deconvolution.