Due to the increasing demand for security, the development of intelligent surveillance systems has attracted considerable attention in recent years. This study aims to develop a system that is able to identify whether...Due to the increasing demand for security, the development of intelligent surveillance systems has attracted considerable attention in recent years. This study aims to develop a system that is able to identify whether or not the people need help in a public place. Different from previous work, our work considers not only the behaviors of the target person but also the interaction between him and nearby people. In the paper, we propose an event alarm system which can detect the human behaviors and recognize the happening event through integrating the results generated from the single and group behavior analysis. Several new effective features are proposed in the study. Besides, a mechanism capable of extracting one-to-one and multiple-to-one relations is also developed. Experimental results show that the proposed approach can correctly detect human behaviors and provide the alarm messages when emergency events occur.展开更多
Group key security protocols play an important role in today’s communication systems. Their verification, however, remains a great challenge because of the dynamic characteristics of group key construction and distri...Group key security protocols play an important role in today’s communication systems. Their verification, however, remains a great challenge because of the dynamic characteristics of group key construction and distribution protocols. Security properties that are well defined in normal two-party protocols have different meanings and different interpretations in group key distribution protocols, specifically, secrecy properties, such as group secrecy, forward secrecy, backward secrecy, and key independence. In this paper, we present a method to verify forward secrecy properties for group-oriented protocols. The method is based on a correct semantical link between group key protocols and event-B models and also uses the refinement process in the B method to model and verify group and forward secrecy. We use an event-B first-order theorem proving system to provide invariant checking for these secrecy properties. We illustrate our approach on the Tree based Group Diffie-Hellman protocol as case study.展开更多
Based on the perspective of psychology,this paper analyzes the causes and characteristics of college students’network mass incidents,explores the psychological factors of college students’network mass incidents,and ...Based on the perspective of psychology,this paper analyzes the causes and characteristics of college students’network mass incidents,explores the psychological factors of college students’network mass incidents,and puts forward the educational strategies to solve college students’network mass incidents:(1)Adhere to humanism and take appeals as the center;(2)To improve the campus network public opinion guidance mechanism under the guidance of relevant social cognition theories;(3)Strengthen communication and improve communication skills;(4)Promote information disclosure and transparency,and eliminate uncertainty and ambiguity.展开更多
Based on the perspective of psychology,this paper analyzes the causes and characteristics of college students’network mass incidents,explores the psychological factors of college students’network mass incidents,and ...Based on the perspective of psychology,this paper analyzes the causes and characteristics of college students’network mass incidents,explores the psychological factors of college students’network mass incidents,and puts forward the educational strategies to solve college students’network mass incidents:No.1.Adhere to humanism and take appeals as the center;No.2.To improve the campus network public opinion guidance mechanism under the guidance of relevant social cognition theories;No.3.Strengthen communication and improve communication skills;No.4.Promote information disclosure and transparency,and eliminate uncertainty and ambiguity.展开更多
The Lomagundi-Jatuli Event（LJE） is one of the largest and earliest positive carbon isotope excursions preserving δ^（13）C_（carb） values between ＋5 and ＋16‰ in Paleoproterozoic carbonates worldwide. However, t...The Lomagundi-Jatuli Event（LJE） is one of the largest and earliest positive carbon isotope excursions preserving δ^（13）C_（carb） values between ＋5 and ＋16‰ in Paleoproterozoic carbonates worldwide. However, the duration, amplitude and patterns of these excursions remain poorly constrained. The 2.14-1.83 Ga Hutuo Group in the North China Craton is a 〉10 km thick volcano-sedimentary sequence, including 〉5 km thick well-preserved carbonates that were deposited in supra-tidal to sub-tidal environments. C-O isotopic and elemental analyses of 152 least altered samples of the carbonates revealed a three-stage δ^（13）C evolution. It began with an exclusively positive δ^（13）C_（carb）（＋1.3 to ＋ 3.4‰） stage in the ~2.1 Ga carbonate in the Dashiling and Qingshicun Formations, followed by a transition from positive values to oscillating positive and negative values in ~3 000 m thick carbonates of the Wenshan, Hebiancun, Jianancun, and Daguandong Formations, and end with exclusively negative δ^（13）C_（carb） values preserved in 〉 500 m thick dolostones of the Huaiyincun and Beidaxing Formations. It appears that much of the LJE, particularly those extremely positive δ^（13）C_（carb） signals, was not recorded in the Hutuo carbonates. The exclusively positive δ^（13）C_（carb） values（＋1.3 to ＋ 3.4‰） preserved in the lower formations likely correspond to the end of the LJE, whereas the subsequent two stages reflect the aftermath of the LJE and the onset of Shunga-Francevillian event（SFE）. The present data point to an increased influence of oxygen on the carbon cycle from the Doucun to the Dongye Subgroups and demonstrate that the termination of the LJE in the North China Craton is nearly simultaneous with those in Fennoscandia and South Africa.展开更多
基金supported by the“MOST”under Grant No.104-2221-E-259-024-MY2
文摘Due to the increasing demand for security, the development of intelligent surveillance systems has attracted considerable attention in recent years. This study aims to develop a system that is able to identify whether or not the people need help in a public place. Different from previous work, our work considers not only the behaviors of the target person but also the interaction between him and nearby people. In the paper, we propose an event alarm system which can detect the human behaviors and recognize the happening event through integrating the results generated from the single and group behavior analysis. Several new effective features are proposed in the study. Besides, a mechanism capable of extracting one-to-one and multiple-to-one relations is also developed. Experimental results show that the proposed approach can correctly detect human behaviors and provide the alarm messages when emergency events occur.
文摘Group key security protocols play an important role in today’s communication systems. Their verification, however, remains a great challenge because of the dynamic characteristics of group key construction and distribution protocols. Security properties that are well defined in normal two-party protocols have different meanings and different interpretations in group key distribution protocols, specifically, secrecy properties, such as group secrecy, forward secrecy, backward secrecy, and key independence. In this paper, we present a method to verify forward secrecy properties for group-oriented protocols. The method is based on a correct semantical link between group key protocols and event-B models and also uses the refinement process in the B method to model and verify group and forward secrecy. We use an event-B first-order theorem proving system to provide invariant checking for these secrecy properties. We illustrate our approach on the Tree based Group Diffie-Hellman protocol as case study.
文摘Based on the perspective of psychology,this paper analyzes the causes and characteristics of college students’network mass incidents,explores the psychological factors of college students’network mass incidents,and puts forward the educational strategies to solve college students’network mass incidents:(1)Adhere to humanism and take appeals as the center;(2)To improve the campus network public opinion guidance mechanism under the guidance of relevant social cognition theories;(3)Strengthen communication and improve communication skills;(4)Promote information disclosure and transparency,and eliminate uncertainty and ambiguity.
文摘Based on the perspective of psychology,this paper analyzes the causes and characteristics of college students’network mass incidents,explores the psychological factors of college students’network mass incidents,and puts forward the educational strategies to solve college students’network mass incidents:No.1.Adhere to humanism and take appeals as the center;No.2.To improve the campus network public opinion guidance mechanism under the guidance of relevant social cognition theories;No.3.Strengthen communication and improve communication skills;No.4.Promote information disclosure and transparency,and eliminate uncertainty and ambiguity.
基金National Natural Science Foundation of China (No. 41272038)National Universities, China University of Geosciences (Wuhan), State Key Laboratory of Biogeology and Environmental Geology,China University of Geosciences (No. GKZ14Y660)+1 种基金the 111 Program for the Ministry of Education of Chinathe State Administration of Foreign Expert Affairs of China (No. B07039)
文摘The Lomagundi-Jatuli Event（LJE） is one of the largest and earliest positive carbon isotope excursions preserving δ^（13）C_（carb） values between ＋5 and ＋16‰ in Paleoproterozoic carbonates worldwide. However, the duration, amplitude and patterns of these excursions remain poorly constrained. The 2.14-1.83 Ga Hutuo Group in the North China Craton is a 〉10 km thick volcano-sedimentary sequence, including 〉5 km thick well-preserved carbonates that were deposited in supra-tidal to sub-tidal environments. C-O isotopic and elemental analyses of 152 least altered samples of the carbonates revealed a three-stage δ^（13）C evolution. It began with an exclusively positive δ^（13）C_（carb）（＋1.3 to ＋ 3.4‰） stage in the ~2.1 Ga carbonate in the Dashiling and Qingshicun Formations, followed by a transition from positive values to oscillating positive and negative values in ~3 000 m thick carbonates of the Wenshan, Hebiancun, Jianancun, and Daguandong Formations, and end with exclusively negative δ^（13）C_（carb） values preserved in 〉 500 m thick dolostones of the Huaiyincun and Beidaxing Formations. It appears that much of the LJE, particularly those extremely positive δ^（13）C_（carb） signals, was not recorded in the Hutuo carbonates. The exclusively positive δ^（13）C_（carb） values（＋1.3 to ＋ 3.4‰） preserved in the lower formations likely correspond to the end of the LJE, whereas the subsequent two stages reflect the aftermath of the LJE and the onset of Shunga-Francevillian event（SFE）. The present data point to an increased influence of oxygen on the carbon cycle from the Doucun to the Dongye Subgroups and demonstrate that the termination of the LJE in the North China Craton is nearly simultaneous with those in Fennoscandia and South Africa.
