The differences among the extended Canetti ＆ Krawezyk 2007 model （ECK2007） and other four models, i.e., the Bellare ＆ Rogaway （1993, 1995）models （BR93,BR95）, the Bellare, Pointcheval ＆ Rogaway （2000） model ...The differences among the extended Canetti ＆ Krawezyk 2007 model （ECK2007） and other four models, i.e., the Bellare ＆ Rogaway （1993, 1995）models （BR93,BR95）, the Bellare, Pointcheval ＆ Rogaway （2000） model （BPR2000） and the Canetti ＆ Krawczyk （2001） model （CK2001） are given. The relative strength of security among these models is analyzed. To support the implication or non-implication relation among these models, the formal proof or the counter-example is provided.展开更多
By using the Lagrange interpolation formula and the technology of signature of equality, a (k, n) threshold nominative proxy signature scheme is proposed, where an original signer delegates his (her) signing power to ...By using the Lagrange interpolation formula and the technology of signature of equality, a (k, n) threshold nominative proxy signature scheme is proposed, where an original signer delegates his (her) signing power to a proxy, who generates a nominative signature on behalf of the original signer and only k or more active verifiers in the n nominees (verifiers) nominated by the proxy signer can verify the signature signed by the proxy. If necessary, these (k or more) active nominees (verifiers) can prove its validity to a third party. In this scheme, the secret shares are generated and en- crypted by the original signer. At the same time, the ciphertexts of the secret shares are used as parts of the signature. Then, the secret shares need not be sent to the nominees (verifiers) secretly. The ordinary nominative proxy signature can be viewed as a (1, 1) threshold nominative proxy signature. The ordinary nominative proxy signature can be viewed as a special case of a (k, n) threshold nominative proxy signature. According to the security analysis of this paper, it is found that our scheme is secure against a proxy signing key forgery attack and existential forgery on an adaptive chosen message attack.展开更多
Digital evidences can be obtained from computers and various kinds of digital devices, such as telephones, mp3/mp4 players, printers, cameras, etc. Telephone Call Detail Records （CDRs） are one important source of di...Digital evidences can be obtained from computers and various kinds of digital devices, such as telephones, mp3/mp4 players, printers, cameras, etc. Telephone Call Detail Records （CDRs） are one important source of digital evidences that can identify suspects and their partners. Law enforcement authorities may intercept and record specific conversations with a court order and CDRs can be obtained from telephone service providers. However, the CDRs of a suspect for a period of time are often fairly large in volume. To obtain useful information and make appropriate decisions automatically from such large amount of CDRs become more and more difficult. Current analysis tools are designed to present only numerical results rather than help us make useful decisions. In this paper, an algorithm based on Fuzzy Decision Tree （FDT） for analyzing CDRs is proposed. We conducted experimental evaluation to verify the proposed algorithm and the result is very promising.展开更多
Nowadays, an increasing number of web applications require identification registration. However, the behavior of website registration has not ever been thoroughly studied. We use the database provided by the Chinese S...Nowadays, an increasing number of web applications require identification registration. However, the behavior of website registration has not ever been thoroughly studied. We use the database provided by the Chinese Software Develop Net (CSDN) to provide a complete perspective on this research point. We concentrate on the following three aspects: complexity, correlation, and preference. From these analyses, we draw the following conclusions: firstly, a considerable number of users have not realized the importance of identification and are using very simple identifications that can be attacked very easily. Secondly, there is a strong complexity correlation among the three parts of identification. Thirdly, the top three passwords that users like are 123456789, 12345678 and 11111111, and the top three email providers that they prefer are NETEASE, qq and sina. Further, we provide some suggestions to improve the quality of user passwords.展开更多
The rate of food insecurity has increased tremendously over the past decade in Canada. This increase has been more pronounced in rural and remote areas especially among Aboriginal peoples. Substantial studies indicate...The rate of food insecurity has increased tremendously over the past decade in Canada. This increase has been more pronounced in rural and remote areas especially among Aboriginal peoples. Substantial studies indicated that nearly half of the on-reserve Aboriginal households in British Columbia （BC） suffer from some degree of food insecurity. Despite the valuable research about obtaining traditional food, the issue of access to market food has been less discussed in the literature. The aim of this study was to assess the local food environment of on-reserve Aboriginal peoples by using a proximity-based approach tool in terms of access to healthy food stores such as supermarket and grocery stores. In the first stage, the addresses of all healthy food stores were geocoded into a map layer. Then the locations of Aboriginal reserves were geocoded to a separate map layer. In the second stage, using ＂Closest Facility Analysis＂ tool in ArcGIS Version 10.3, the distance based on a 15-minute driving time was measured from each reserve to the closest healthy food destination on CanMapRouteLogistics network. The results indicated that 25% of Aboriginal reserves did not have reasonable access to healthy food stores. We concluded that Aboriginal peoples in low access rural reserves with lower socioeconomic status are at potential risk of perpetuate food insecurity.展开更多
Factor graph, so named because it graphically represents function factorization, with which and its sum-product algorithm the iterative algorithm can be derived clearly. An iterative multiuser receiver based on factor...Factor graph, so named because it graphically represents function factorization, with which and its sum-product algorithm the iterative algorithm can be derived clearly. An iterative multiuser receiver based on factor graph for asynchronous coded CDMA system is proposed. In this paper, the a posteriori probability of users information bits conditioned on the noise-whitening filters output is represented by factor graphs, after numbers of iterations with the sum-product algorithm the information bits are estimated. The authors also propose a reduced complexity algorithm. Simulation results show that with this proposed receiver, near-single-user performance can be achieved, and small performance degradation for the reduced complexity algorithm with significant complexity reduction.展开更多
文摘The differences among the extended Canetti ＆ Krawezyk 2007 model （ECK2007） and other four models, i.e., the Bellare ＆ Rogaway （1993, 1995）models （BR93,BR95）, the Bellare, Pointcheval ＆ Rogaway （2000） model （BPR2000） and the Canetti ＆ Krawczyk （2001） model （CK2001） are given. The relative strength of security among these models is analyzed. To support the implication or non-implication relation among these models, the formal proof or the counter-example is provided.
基金Projects 60473028 supported by the National Natural Science Foundation of China and 2006XXJ17 by the Natural Science Foundation of Zhengzhou Universityof Light Industry
文摘By using the Lagrange interpolation formula and the technology of signature of equality, a (k, n) threshold nominative proxy signature scheme is proposed, where an original signer delegates his (her) signing power to a proxy, who generates a nominative signature on behalf of the original signer and only k or more active verifiers in the n nominees (verifiers) nominated by the proxy signer can verify the signature signed by the proxy. If necessary, these (k or more) active nominees (verifiers) can prove its validity to a third party. In this scheme, the secret shares are generated and en- crypted by the original signer. At the same time, the ciphertexts of the secret shares are used as parts of the signature. Then, the secret shares need not be sent to the nominees (verifiers) secretly. The ordinary nominative proxy signature can be viewed as a (1, 1) threshold nominative proxy signature. The ordinary nominative proxy signature can be viewed as a special case of a (k, n) threshold nominative proxy signature. According to the security analysis of this paper, it is found that our scheme is secure against a proxy signing key forgery attack and existential forgery on an adaptive chosen message attack.
文摘Digital evidences can be obtained from computers and various kinds of digital devices, such as telephones, mp3/mp4 players, printers, cameras, etc. Telephone Call Detail Records （CDRs） are one important source of digital evidences that can identify suspects and their partners. Law enforcement authorities may intercept and record specific conversations with a court order and CDRs can be obtained from telephone service providers. However, the CDRs of a suspect for a period of time are often fairly large in volume. To obtain useful information and make appropriate decisions automatically from such large amount of CDRs become more and more difficult. Current analysis tools are designed to present only numerical results rather than help us make useful decisions. In this paper, an algorithm based on Fuzzy Decision Tree （FDT） for analyzing CDRs is proposed. We conducted experimental evaluation to verify the proposed algorithm and the result is very promising.
基金supported by the Foundation for Key Program of Ministry of Education, China under Grant No.311007National Science Foundation Project of China under Grants No. 61202079, No.61170225, No.61271199+1 种基金the Fundamental Research Funds for the Central Universities under Grant No.FRF-TP-09-015Athe Fundamental Research Funds in Beijing Jiaotong University under Grant No.W11JB00630
文摘Nowadays, an increasing number of web applications require identification registration. However, the behavior of website registration has not ever been thoroughly studied. We use the database provided by the Chinese Software Develop Net (CSDN) to provide a complete perspective on this research point. We concentrate on the following three aspects: complexity, correlation, and preference. From these analyses, we draw the following conclusions: firstly, a considerable number of users have not realized the importance of identification and are using very simple identifications that can be attacked very easily. Secondly, there is a strong complexity correlation among the three parts of identification. Thirdly, the top three passwords that users like are 123456789, 12345678 and 11111111, and the top three email providers that they prefer are NETEASE, qq and sina. Further, we provide some suggestions to improve the quality of user passwords.
文摘The rate of food insecurity has increased tremendously over the past decade in Canada. This increase has been more pronounced in rural and remote areas especially among Aboriginal peoples. Substantial studies indicated that nearly half of the on-reserve Aboriginal households in British Columbia （BC） suffer from some degree of food insecurity. Despite the valuable research about obtaining traditional food, the issue of access to market food has been less discussed in the literature. The aim of this study was to assess the local food environment of on-reserve Aboriginal peoples by using a proximity-based approach tool in terms of access to healthy food stores such as supermarket and grocery stores. In the first stage, the addresses of all healthy food stores were geocoded into a map layer. Then the locations of Aboriginal reserves were geocoded to a separate map layer. In the second stage, using ＂Closest Facility Analysis＂ tool in ArcGIS Version 10.3, the distance based on a 15-minute driving time was measured from each reserve to the closest healthy food destination on CanMapRouteLogistics network. The results indicated that 25% of Aboriginal reserves did not have reasonable access to healthy food stores. We concluded that Aboriginal peoples in low access rural reserves with lower socioeconomic status are at potential risk of perpetuate food insecurity.
基金the National Science Foundation of China and Key Subject Project of the Ministry of Education.
文摘Factor graph, so named because it graphically represents function factorization, with which and its sum-product algorithm the iterative algorithm can be derived clearly. An iterative multiuser receiver based on factor graph for asynchronous coded CDMA system is proposed. In this paper, the a posteriori probability of users information bits conditioned on the noise-whitening filters output is represented by factor graphs, after numbers of iterations with the sum-product algorithm the information bits are estimated. The authors also propose a reduced complexity algorithm. Simulation results show that with this proposed receiver, near-single-user performance can be achieved, and small performance degradation for the reduced complexity algorithm with significant complexity reduction.
