A privilege flow oriented intrusion detection method based on HSMM (Hidden semi-Markov Model) is discussed. The privilege flow model and HSMM are incorporated in the implementation of an anomaly detection IDS (Intrusi...A privilege flow oriented intrusion detection method based on HSMM (Hidden semi-Markov Model) is discussed. The privilege flow model and HSMM are incorporated in the implementation of an anomaly detection IDS (Intrusion Detection System). Using the dataset of DARPA 1998, our experiment results reveal good detection performance and acceptable computation cost.展开更多
Based on analyzing the techniques and architecture of existing network Intrusion Detection System (IDS), and probing into the fundament of Immune System (IS), a novel immune model is presented and applied to network I...Based on analyzing the techniques and architecture of existing network Intrusion Detection System (IDS), and probing into the fundament of Immune System (IS), a novel immune model is presented and applied to network IDS, which is helpful to design an effective IDS. Besides, this paper suggests a scheme to represent the self profile of network. And an automated self profile extraction algorithm is provided to extract self profile from packets. The experimental results prove validity of the scheme and algorithm, which is the foundation of the immune model.展开更多
Based on Bayes' theorem we point out that the false positive rate must be lower than the intrusion base rate in order to make the Alarm Credibility Probability of the intrusion detection system exceed 50%. We pres...Based on Bayes' theorem we point out that the false positive rate must be lower than the intrusion base rate in order to make the Alarm Credibility Probability of the intrusion detection system exceed 50%. We present the methods that have been used in our developing intrusion detection system AIIDS (artificial immune intrusion detection systems) to increase the creditability of anomaly detection system. These methods include increasing the regularities of the system call trace by use of Hidden Markov Model (HMM), making every antibody or detector has finite lifetime, offering the detector a co-stimulate signal to illustrate whether there is damage in the system according to the integrity, confidentiality, or availability of the system resource.展开更多
The input document images with skew can be a serious problem in the optical character recognition system. A method is proposed for skew detection in binary document images using mathematic morphology. The basic proces...The input document images with skew can be a serious problem in the optical character recognition system. A method is proposed for skew detection in binary document images using mathematic morphology. The basic process of our approach consists of three steps: Firstly, a dilation operation is applied to the binary image; Secondly, the dilated image is thinned; Finally, the skew angle is detected using the Hough transform. The proposed approach with high precision can detect skew with large angle (?90δ-90Δ). The experimental result shows this method is applicable and efficient.展开更多
China’s financial conundrum arises from two sources: (1) its large trade (saving) surplus results in a currency mismatch because it is an immature creditor that cannot lend in its own currency. Instead foreign curren...China’s financial conundrum arises from two sources: (1) its large trade (saving) surplus results in a currency mismatch because it is an immature creditor that cannot lend in its own currency. Instead foreign currency claims (largely dollars) build up within domestic financial institutions. And (2) economists – both American and Chinese – mistakenly attribute the surpluses to an undervalued renminbi. To placate the United States, the result is a gradual appreciation of the renminbi against the dollar of 6% or more per year. This predictable appreciation since 2004, and the fall in US interest rates since mid 2007, not only attracts hot money inflows but inhibits private capital outflows from financing China’s huge trade surplus. This one-way bet in the foreign exchange markets can no longer be offset by relatively low interest rates in China compared to the United States, as had been the case in 2005-06. Thus, the People’s Bank of China (PBOC) now must intervene heavily to prevent the renminbi from ratcheting upwards – and so becomes the country’s sole international financial intermediary. Despite massive efforts by the PBOC to sterilize the monetary consequences of the reserve buildup, inflation in China is increasing, with excess liquidity that spills over into the world economy. China has been transformed from a deflationary force on American and European price levels into an inflationary one. Because of the currency mismatch, floating the RMB is neither feasible nor desirable – and a higher RMB would not reduce China’s trade surplus. Instead, monetary control and normal private-sector finance for the trade surplus require a return to a credibly fixed nominal yuan/dollar rate similar to that which existed between 1995 and 2004. But for any newly reset yuan/dollar rate to be credible as a monetary anchor, foreign "China bashing" to get the RMB up must end. Currency stabilization would allow the PBOC to regain monetary control and quash inflation. Only then can the Chinese government take decisive steps to reduce the trade (saving) surplus by tax cuts, increased social expenditures, and higher dividend payouts. But as long as the economy remains overheated, the government hesitates to take these trade-surplus-reduction measures because of their near-term inflationary consequences.展开更多
Focusing on the 18 counties along “One River and Two Tributaries” region, and based on the data from China 3nl, 4th and 5th population censuses, this article has analyzed the time and spatial changing patterns of th...Focusing on the 18 counties along “One River and Two Tributaries” region, and based on the data from China 3nl, 4th and 5th population censuses, this article has analyzed the time and spatial changing patterns of the population in this region. The analyses show that since the 3nl population census, total population, average age and total birth rate have all changed considerably: ① Total population has grown, fast, with most counties' annual average growth rate of more than 10. ② In terms of the region's average age, in 2000 the age in the 18 counties is younger than 30 years old. ③ Compared with the 3nl population census, labor force by the 5th census is much younger. ④ Countermeasures are proposed to control population by controlling birth rate as the result of the local resident's quality improvement by education.展开更多
As a kind of parallel storage system, RAID5 has been becoming a popular solution for providing better performance at low cost and without sacrificing much redundant data, its main disadvantage is poor performance. It ...As a kind of parallel storage system, RAID5 has been becoming a popular solution for providing better performance at low cost and without sacrificing much redundant data, its main disadvantage is poor performance. It is a general method to improve RAID5 performance by using cache. However, it often happens that the data is not hit in cache, in this case, the RAID5 performance also will be very poor. The method based on combination of disk I/O operations has been proposed for impriving the I/O response time through reducing the number of low-level operations. According to theoretic analysis and experimental test, we find that RAID5 access time and data transfer rate could be largely improved than conventional method.展开更多
文摘A privilege flow oriented intrusion detection method based on HSMM (Hidden semi-Markov Model) is discussed. The privilege flow model and HSMM are incorporated in the implementation of an anomaly detection IDS (Intrusion Detection System). Using the dataset of DARPA 1998, our experiment results reveal good detection performance and acceptable computation cost.
基金the National Natural Science Foundation of China(69983005)and the Research Fund for the Doctoral Program of Higher Education(RFDP1999048602)
文摘Based on analyzing the techniques and architecture of existing network Intrusion Detection System (IDS), and probing into the fundament of Immune System (IS), a novel immune model is presented and applied to network IDS, which is helpful to design an effective IDS. Besides, this paper suggests a scheme to represent the self profile of network. And an automated self profile extraction algorithm is provided to extract self profile from packets. The experimental results prove validity of the scheme and algorithm, which is the foundation of the immune model.
文摘Based on Bayes' theorem we point out that the false positive rate must be lower than the intrusion base rate in order to make the Alarm Credibility Probability of the intrusion detection system exceed 50%. We present the methods that have been used in our developing intrusion detection system AIIDS (artificial immune intrusion detection systems) to increase the creditability of anomaly detection system. These methods include increasing the regularities of the system call trace by use of Hidden Markov Model (HMM), making every antibody or detector has finite lifetime, offering the detector a co-stimulate signal to illustrate whether there is damage in the system according to the integrity, confidentiality, or availability of the system resource.
文摘The input document images with skew can be a serious problem in the optical character recognition system. A method is proposed for skew detection in binary document images using mathematic morphology. The basic process of our approach consists of three steps: Firstly, a dilation operation is applied to the binary image; Secondly, the dilated image is thinned; Finally, the skew angle is detected using the Hough transform. The proposed approach with high precision can detect skew with large angle (?90δ-90Δ). The experimental result shows this method is applicable and efficient.
文摘China’s financial conundrum arises from two sources: (1) its large trade (saving) surplus results in a currency mismatch because it is an immature creditor that cannot lend in its own currency. Instead foreign currency claims (largely dollars) build up within domestic financial institutions. And (2) economists – both American and Chinese – mistakenly attribute the surpluses to an undervalued renminbi. To placate the United States, the result is a gradual appreciation of the renminbi against the dollar of 6% or more per year. This predictable appreciation since 2004, and the fall in US interest rates since mid 2007, not only attracts hot money inflows but inhibits private capital outflows from financing China’s huge trade surplus. This one-way bet in the foreign exchange markets can no longer be offset by relatively low interest rates in China compared to the United States, as had been the case in 2005-06. Thus, the People’s Bank of China (PBOC) now must intervene heavily to prevent the renminbi from ratcheting upwards – and so becomes the country’s sole international financial intermediary. Despite massive efforts by the PBOC to sterilize the monetary consequences of the reserve buildup, inflation in China is increasing, with excess liquidity that spills over into the world economy. China has been transformed from a deflationary force on American and European price levels into an inflationary one. Because of the currency mismatch, floating the RMB is neither feasible nor desirable – and a higher RMB would not reduce China’s trade surplus. Instead, monetary control and normal private-sector finance for the trade surplus require a return to a credibly fixed nominal yuan/dollar rate similar to that which existed between 1995 and 2004. But for any newly reset yuan/dollar rate to be credible as a monetary anchor, foreign "China bashing" to get the RMB up must end. Currency stabilization would allow the PBOC to regain monetary control and quash inflation. Only then can the Chinese government take decisive steps to reduce the trade (saving) surplus by tax cuts, increased social expenditures, and higher dividend payouts. But as long as the economy remains overheated, the government hesitates to take these trade-surplus-reduction measures because of their near-term inflationary consequences.
文摘Focusing on the 18 counties along “One River and Two Tributaries” region, and based on the data from China 3nl, 4th and 5th population censuses, this article has analyzed the time and spatial changing patterns of the population in this region. The analyses show that since the 3nl population census, total population, average age and total birth rate have all changed considerably: ① Total population has grown, fast, with most counties' annual average growth rate of more than 10. ② In terms of the region's average age, in 2000 the age in the 18 counties is younger than 30 years old. ③ Compared with the 3nl population census, labor force by the 5th census is much younger. ④ Countermeasures are proposed to control population by controlling birth rate as the result of the local resident's quality improvement by education.
基金Supported by the National Natural Science Foundation of China under grant6 97730 46 and(6 99730 17) and Defense Advanced Resea
文摘As a kind of parallel storage system, RAID5 has been becoming a popular solution for providing better performance at low cost and without sacrificing much redundant data, its main disadvantage is poor performance. It is a general method to improve RAID5 performance by using cache. However, it often happens that the data is not hit in cache, in this case, the RAID5 performance also will be very poor. The method based on combination of disk I/O operations has been proposed for impriving the I/O response time through reducing the number of low-level operations. According to theoretic analysis and experimental test, we find that RAID5 access time and data transfer rate could be largely improved than conventional method.