Database Security and Protection System (DSPS) is a security platform for fighting malicious DBMS. The security and performance are critical to DSPS. The authors suggested a key management scheme by combining the serv...Database Security and Protection System (DSPS) is a security platform for fighting malicious DBMS. The security and performance are critical to DSPS. The authors suggested a key management scheme by combining the server group structure to improve availability and the key distribution structure needed by proactive security. This paper detailed the implementation of proactive security in DSPS. After thorough performance analysis, the authors concluded that the performance difference between the replicated mechanism and proactive mechanism becomes smaller and smaller with increasing number of concurrent connections; and that proactive security is very useful and practical for large, critical applications.展开更多
Objective：To evaluate the safety and efficiency of transvenous embolization of dural arteriovenous fistula of cavernous region by multiple venous routes. Methods： Twenty seven patients with dural arteriovenous fistu...Objective：To evaluate the safety and efficiency of transvenous embolization of dural arteriovenous fistula of cavernous region by multiple venous routes. Methods： Twenty seven patients with dural arteriovenous fistula of cavernous region were treated by transvenous embolization with micro-coils. The transvenous routes included inferior petrosal sinus, superior ophthalmic vein and facial vein. Results： Clinical cure was achieved in 23 cases and significant improvement of symptoms in 4 cases. Complete anglographic obliteration was documented in 22 patients （82%）. Residual shunting were left in 2 patients via pterygoid drainage and 1 case via inter-cavernous sinus, 2 cases via inferior petrosal sinus, disappeared one month later by manual compression carotid artery. Headache and vomiting were the most common symptoms after embolization. Three patients had diplopia and relieved within two months after embolization. There was no permanent procedure-related morbidity. The clinic follow up ranged from 5 months to 6 years, and there was not recurrence case. Conclusion： Transvenous embolization via different venous routes is a safe and efficient method for dural arteriovenous fistula of cavernous region treatment.展开更多
According to the SRAM-based FPGA's single event effect problem in space application,single event upset induced multi-block error(SEU-MBE) phenomenon and its mitigation strategy are studied in the paper.After analy...According to the SRAM-based FPGA's single event effect problem in space application,single event upset induced multi-block error(SEU-MBE) phenomenon and its mitigation strategy are studied in the paper.After analyzing the place and route result,the paper points out that the essence of SEU-MBE is that some important modules exceed the safe internal distance.Two approaches,area constraint method(ACM) and incremental route algorithm(IRA),are proposed,which can reduce the error rate by manipulating programmable switch matrix and interconnection points within FPGA route resource.Fault injection experiments indicate that error detection rate is above 98.6% for both strategies,and FPGA resources increment and performance penalty are around 10%.展开更多
文摘Database Security and Protection System (DSPS) is a security platform for fighting malicious DBMS. The security and performance are critical to DSPS. The authors suggested a key management scheme by combining the server group structure to improve availability and the key distribution structure needed by proactive security. This paper detailed the implementation of proactive security in DSPS. After thorough performance analysis, the authors concluded that the performance difference between the replicated mechanism and proactive mechanism becomes smaller and smaller with increasing number of concurrent connections; and that proactive security is very useful and practical for large, critical applications.
文摘Objective：To evaluate the safety and efficiency of transvenous embolization of dural arteriovenous fistula of cavernous region by multiple venous routes. Methods： Twenty seven patients with dural arteriovenous fistula of cavernous region were treated by transvenous embolization with micro-coils. The transvenous routes included inferior petrosal sinus, superior ophthalmic vein and facial vein. Results： Clinical cure was achieved in 23 cases and significant improvement of symptoms in 4 cases. Complete anglographic obliteration was documented in 22 patients （82%）. Residual shunting were left in 2 patients via pterygoid drainage and 1 case via inter-cavernous sinus, 2 cases via inferior petrosal sinus, disappeared one month later by manual compression carotid artery. Headache and vomiting were the most common symptoms after embolization. Three patients had diplopia and relieved within two months after embolization. There was no permanent procedure-related morbidity. The clinic follow up ranged from 5 months to 6 years, and there was not recurrence case. Conclusion： Transvenous embolization via different venous routes is a safe and efficient method for dural arteriovenous fistula of cavernous region treatment.
基金supported by the National High Technology Research and Development Program of China ("863" Program) (Grant No. 2006SQ710375)the Civil Aerospace Technologies Advanced Research Pro-gram of China (Grant No. C1320061301)Ministries and Commissions’Advanced Research Found of China (Grant No. 9140A20070209KG0160)
文摘According to the SRAM-based FPGA's single event effect problem in space application,single event upset induced multi-block error(SEU-MBE) phenomenon and its mitigation strategy are studied in the paper.After analyzing the place and route result,the paper points out that the essence of SEU-MBE is that some important modules exceed the safe internal distance.Two approaches,area constraint method(ACM) and incremental route algorithm(IRA),are proposed,which can reduce the error rate by manipulating programmable switch matrix and interconnection points within FPGA route resource.Fault injection experiments indicate that error detection rate is above 98.6% for both strategies,and FPGA resources increment and performance penalty are around 10%.
