In order to avoid the noise and over fitting and further improve the limited classification performance of the real decision tree, a traffic incident detection method based on the random forest algorithm is presented....In order to avoid the noise and over fitting and further improve the limited classification performance of the real decision tree, a traffic incident detection method based on the random forest algorithm is presented. From the perspective of classification strength and correlation, three experiments are performed to investigate the potential application of random forest to traffic incident detection： comparison with a different number of decision trees; comparison with different decision trees; comparison with the neural network. The real traffic data of the 1-880 database is used in the experiments. The detection performance is evaluated by the common criteria including the detection rate, the false alarm rate, the mean time to detection, the classification rate and the area under the curve of the receiver operating characteristic （ROC）. The experimental results indicate that the model based on random forest can improve the decision rate, reduce the testing time, and obtain a higher classification rate. Meanwhile, it is competitive compared with multi-layer feed forward neural networks （MLF）.展开更多
Most transactional memory (TM) research focused on multi-core processors, and others investigated at the clusters, leaving the area of non-uniform memory access (NUMA) system unexplored. The existing TM implementation...Most transactional memory (TM) research focused on multi-core processors, and others investigated at the clusters, leaving the area of non-uniform memory access (NUMA) system unexplored. The existing TM implementations made significant performance degradation on NUMA system because they ignored the slower remote memory access. To solve this problem, a latency-based conflict detection and a forecasting-based conflict prevention method were proposed. Using these techniques, the NUMA aware TM system was presented. By reducing the remote memory access and the abort rate of transaction, the experiment results show that the NUMA aware strategies present good practical TM performance on NUMA system.展开更多
Recently, there has been a radial shift from traditional online social networks to content-generated social networks(CGSNs). Contemporary CGSNs, such as Dianping and Trip Advisor, are often the targets of click farmin...Recently, there has been a radial shift from traditional online social networks to content-generated social networks(CGSNs). Contemporary CGSNs, such as Dianping and Trip Advisor, are often the targets of click farming in which fake reviews are posted in order to boost or diminish the ratings of listed products and services simply through clicking. Click farming often emanates from a collection of multiple fake or compromised accounts, which we call click farmers. In this paper, we conduct a three-phase methodology to detect click farming. We begin by clustering communities based on newly-defined collusion networks. We then apply the Louvain community detection method to detecting communities. We finally perform a binary classification on detected-communities. Our results of over a year-long study show that(1) the prevalence of click farming is different across CGSNs;(2) most click farmers are lowly-rated;(3) click-farming communities have relatively tight relations between users;(4) more highly-ranked stores have a greater portion of fake reviews.展开更多
The genetically modified high-oleic rapeseed （Brassica napus L.） line W-4 was obtained by transforming a binary vector which harbored an inverted repeat expression cassette of fad2 gene into the rapeseed cultivar We...The genetically modified high-oleic rapeseed （Brassica napus L.） line W-4 was obtained by transforming a binary vector which harbored an inverted repeat expression cassette of fad2 gene into the rapeseed cultivar Westar.The transformation was mediated by Agrobacterium.The flanking sequences to both the left and right borders of T-DNA insertion site were amplified by thermal asymmetric interlaced PCR （TAIL-PCR） from the genomic DNA of the transgenic rapeseed line W-4.The flanking sequences to the right border was 290 bp in length and the nucleotide composition was 31.27％ for G＋C content while 68.73％ for A＋T content.The flanking sequence to the left border was 365 bp in length and the G＋C content was 32.6％ and the A＋T content was 67.4％,indicating that the T-DNA was integrated in the A/T-rich region.Further more,sequence alignment analysis showed a deletion of 62 bp including the right border of pCNFIRnos and the integration of the whole left border except a change of G to A.That was to say,the integration of the T-DNA in the transgenic line W-4 not involved in the vector sequences.Based on both flanking sequences as well as the left and right borders of the T-DNA sequences,two pairs of specific primers TLF/TLR and TRF/TRR were designed.Using the primers the event-specific PCR detection method for transgenic rapeseed line W-4 was established.By the PCR,two fragments of 485 and 405 bp were amplified from the W-4 genomic DNA as expected,while no products were amplified from the genomic DNA of other transgenic rapeseed lines and non-transgenic rapeseed line.And by the PCR it is possible to detect the W-4 genomic DNA from a mixed sample of genomic DNA.The limit of the detection for the qualitative PCR assay was 0.1％.The method developed in this work is highly specific,sensitive and suitable for event-specific detection of the transgenic rapeseed line W-4.展开更多
Semantic video analysis plays an important role in the field of machine intelligence and pattern recognition. In this paper, based on the Hidden Markov Model (HMM), a semantic recognition framework on compressed video...Semantic video analysis plays an important role in the field of machine intelligence and pattern recognition. In this paper, based on the Hidden Markov Model (HMM), a semantic recognition framework on compressed videos is proposed to analyze the video events according to six low-level features. After the detailed analysis of video events, the pattern of global motion and five features in foreground—the principal parts of videos, are employed as the observations of the Hidden Markov Model to classify events in videos. The applications of the proposed framework in some video event detections demonstrate the promising success of the proposed framework on semantic video analysis.展开更多
Whether recent Arctic sea ice loss is responsible for recent severe winters over mid-latitude continents has emerged as a major debate among climate scientists owing to short records of observations and large internal...Whether recent Arctic sea ice loss is responsible for recent severe winters over mid-latitude continents has emerged as a major debate among climate scientists owing to short records of observations and large internal variability in mid- and high-latitudes. In this study, the authors divide the evolution of autumn Arctic sea ice extent during 1979–2014 into three epochs, 1979–1986（high）, 1987–2006（moderate）, and 2007–2014（low）, using a regime shift identification method. The authors then compare the associations between autumn Arctic sea ice and winter climate anomalies over central and eastern Eurasia for the three epochs with a focus on extreme events. The results show robust and detectable signals of Arctic sea ice loss in weather and climate over western Siberia and East Asia. Associated with sea ice loss, the latitude（speed） of the jet stream shifts southward（reduces）,the wave extent amplifies, and blocking high events increase over the Ural Mountains, leading to increased frequency of cold air outbreaks extending from central Asia to northeast China. These associations bear a high degree of similarity to the observed atmospheric anomalies during the low sea ice epoch. By contrast, the patterns of atmospheric anomalies for the high sea ice epoch are different from those congruent with sea ice variability, which is related to the persistent negative phase of the Arctic Oscillation.展开更多
The impact of temporal variation of rainfall on the relationship between rainfall and catchment response is investigated in a catchment with high temporally variable rainfalls and a high percentage of permeable soils ...The impact of temporal variation of rainfall on the relationship between rainfall and catchment response is investigated in a catchment with high temporally variable rainfalls and a high percentage of permeable soils in the southwest of Iran.Twenty-nine storm events are classified into two classes, High Temporal heterogeneous(HT) and Low Temporal heterogeneous(LT) events using the variogram technique and the storm events of each class are analyzed to detect the relationship between Curve Number(CN) and rainfall depth. It is found that there is not a similar correlation between CN values and rainfall depths for both temporally variable classes, and hence, two different responses can be observed in the catchment according to rainfall temporal heterogeneities. For HT events, a complacent behavior is detected in which the CNs decline as rainfall depth increases while a different response, violent behavior, is observed for LT events in which the CNs rise and asymptotically approach a constant value with increasing storm size. This considerable difference between CN-P relationships derived from the two temporally variable classes of rainfall is attributed to the provocation of different runoff generation mechanisms, infiltration-excess and saturation-excess caused by rainfall temporal heterogeneities. Moreover, the results support the validity of variogram technique to classify storm events into two LT and HT classes.展开更多
How to quickly and accurately detect new topics from massive data online becomes a main problem of public opinion monitoring in cyberspace. This paperpresents a new event detection method for the current new event det...How to quickly and accurately detect new topics from massive data online becomes a main problem of public opinion monitoring in cyberspace. This paperpresents a new event detection method for the current new event detection system, based on sorted subtopic matching algorithm and constructs the entire design framework. In this p^per, the subtopics contained in old topics （or news stories） are sorted in descending order according to their importance to the topic（or news stories）, and form a sorted subtopic sequence. In the process of subtopic matching, subtopic scoring matrix is used to determine whether a new story is reporting a new event. Experimental results show that the sorted subtopic matching model improved the accuracy and effectiveness ofthenew event detection system in cyberspace.展开更多
An algorithm for detecting low-frequency seismic events is developed and applied to the detection of low-frequency events before the 2008 Wenchuan and the 2013 Lushan earthquakes. Continuous vertical-component wavefor...An algorithm for detecting low-frequency seismic events is developed and applied to the detection of low-frequency events before the 2008 Wenchuan and the 2013 Lushan earthquakes. Continuous vertical-component waveforms of some broadband stations in the few months before the Wenchuan and Lushan earthquakes are processed by applying a bandpass filter in 2- 8Hz,and then converted to envelopes with a smoothing time of 10 s window and a median filter with a 20 min window. As a result,teleseismic,long-period noise and local small earthquakes are removed,the filtered amplitude is obviously larger than that of the noise and lasts for a dozen minutes to several hours during a few days in a few stations before the Wenchuan and Lushan earthquakes,respectively. The waveform and envelope are similar to that of a non-volcanic tremor( NVT). There are suspected NVT before the two earthquakes. Preliminary application demonstrates that this algorithm is potentially useful for extracting NVT signals from continuous seismic waveforms.展开更多
Since the implementation of the rules of the supplement and correction of the defective evidences, there are many problems in the practice. The actual investigations and researches also feedback that the judges also h...Since the implementation of the rules of the supplement and correction of the defective evidences, there are many problems in the practice. The actual investigations and researches also feedback that the judges also have a lot of problems in the face of the definition of the meaning of the defective evidences, the correction application, and the degree restrictions. Behind this reflects the contradiction between the stress of the prosecution organs in the criminal detection and the deepening of the resisting mechanism in the court. And the litigation structure of the ＂division of responsibilities among three authorities＂ and the trial mode of ＂the centralism of the book records of the cases＂ exacerbated this opposition. On the basis of clarifying the origin and the meanings of the defective evidences, the author of this paper analyzes the essence and its harm of the rule. Through the reflections of the problems existing in the practice, the author further defines the two types of the ＂defects＂ that shall not be allowed to correct.展开更多
Objective： To explore the fundamental theory, methods and data of the quality of life （QOL） of soldiers and its influence factors in the first response army. Methods： Totally 215 soldiers in the first response arm...Objective： To explore the fundamental theory, methods and data of the quality of life （QOL） of soldiers and its influence factors in the first response army. Methods： Totally 215 soldiers in the first response army of a military area in China were inquired by using self-regulating questionnaire and WHOQOL-BREF （Chinese Edition）. Resalts： WHOQOL-BREF had good acceptability, reliability and validity in the first response army. QOL of soldiers in the first response army was middling. The influencing factors of QOL of the soldiers in first army includes self-report health, different areas where the army men come from, different arms of services, whether only child in family. And the difference was statistically significant. Conclusion： WHOQOL-BREF is fit for evaluating the quality of life of soldiers in the first response army. There are differences of the quality of life among the soldiers in the first response army. So we should take appropriate measures to improve the soldiers＇ quality of life.展开更多
基金The National High Technology Research and Development Program of China(863 Program)(No.2012AA112304)the Scientific Innovation Research of College Graduates in Jiangsu Province(No.CXZZ13-0119)
文摘In order to avoid the noise and over fitting and further improve the limited classification performance of the real decision tree, a traffic incident detection method based on the random forest algorithm is presented. From the perspective of classification strength and correlation, three experiments are performed to investigate the potential application of random forest to traffic incident detection： comparison with a different number of decision trees; comparison with different decision trees; comparison with the neural network. The real traffic data of the 1-880 database is used in the experiments. The detection performance is evaluated by the common criteria including the detection rate, the false alarm rate, the mean time to detection, the classification rate and the area under the curve of the receiver operating characteristic （ROC）. The experimental results indicate that the model based on random forest can improve the decision rate, reduce the testing time, and obtain a higher classification rate. Meanwhile, it is competitive compared with multi-layer feed forward neural networks （MLF）.
基金Projects(61003075, 61170261) supported by the National Natural Science Foundation of China
文摘Most transactional memory (TM) research focused on multi-core processors, and others investigated at the clusters, leaving the area of non-uniform memory access (NUMA) system unexplored. The existing TM implementations made significant performance degradation on NUMA system because they ignored the slower remote memory access. To solve this problem, a latency-based conflict detection and a forecasting-based conflict prevention method were proposed. Using these techniques, the NUMA aware TM system was presented. By reducing the remote memory access and the abort rate of transaction, the experiment results show that the NUMA aware strategies present good practical TM performance on NUMA system.
基金supported in part by the National Science Foundation of China,under Grants 71671114,61672350,and U1405251
文摘Recently, there has been a radial shift from traditional online social networks to content-generated social networks(CGSNs). Contemporary CGSNs, such as Dianping and Trip Advisor, are often the targets of click farming in which fake reviews are posted in order to boost or diminish the ratings of listed products and services simply through clicking. Click farming often emanates from a collection of multiple fake or compromised accounts, which we call click farmers. In this paper, we conduct a three-phase methodology to detect click farming. We begin by clustering communities based on newly-defined collusion networks. We then apply the Louvain community detection method to detecting communities. We finally perform a binary classification on detected-communities. Our results of over a year-long study show that(1) the prevalence of click farming is different across CGSNs;(2) most click farmers are lowly-rated;(3) click-farming communities have relatively tight relations between users;(4) more highly-ranked stores have a greater portion of fake reviews.
基金Supported by Key Agricultural Technology Research and Development Program of Jiangsu Province(BE2009304)Fund for National Rapeseed Research System(CARS13)~~
文摘The genetically modified high-oleic rapeseed （Brassica napus L.） line W-4 was obtained by transforming a binary vector which harbored an inverted repeat expression cassette of fad2 gene into the rapeseed cultivar Westar.The transformation was mediated by Agrobacterium.The flanking sequences to both the left and right borders of T-DNA insertion site were amplified by thermal asymmetric interlaced PCR （TAIL-PCR） from the genomic DNA of the transgenic rapeseed line W-4.The flanking sequences to the right border was 290 bp in length and the nucleotide composition was 31.27％ for G＋C content while 68.73％ for A＋T content.The flanking sequence to the left border was 365 bp in length and the G＋C content was 32.6％ and the A＋T content was 67.4％,indicating that the T-DNA was integrated in the A/T-rich region.Further more,sequence alignment analysis showed a deletion of 62 bp including the right border of pCNFIRnos and the integration of the whole left border except a change of G to A.That was to say,the integration of the T-DNA in the transgenic line W-4 not involved in the vector sequences.Based on both flanking sequences as well as the left and right borders of the T-DNA sequences,two pairs of specific primers TLF/TLR and TRF/TRR were designed.Using the primers the event-specific PCR detection method for transgenic rapeseed line W-4 was established.By the PCR,two fragments of 485 and 405 bp were amplified from the W-4 genomic DNA as expected,while no products were amplified from the genomic DNA of other transgenic rapeseed lines and non-transgenic rapeseed line.And by the PCR it is possible to detect the W-4 genomic DNA from a mixed sample of genomic DNA.The limit of the detection for the qualitative PCR assay was 0.1％.The method developed in this work is highly specific,sensitive and suitable for event-specific detection of the transgenic rapeseed line W-4.
基金Supported in part by the National Natural Science Foundation of China (No. 60572045)the Ministry of Education of China Ph.D. Program Foundation (No.20050698033)Cooperation Project (2005.7-2007.6) with Microsoft Research Asia.
文摘Semantic video analysis plays an important role in the field of machine intelligence and pattern recognition. In this paper, based on the Hidden Markov Model (HMM), a semantic recognition framework on compressed videos is proposed to analyze the video events according to six low-level features. After the detailed analysis of video events, the pattern of global motion and five features in foreground—the principal parts of videos, are employed as the observations of the Hidden Markov Model to classify events in videos. The applications of the proposed framework in some video event detections demonstrate the promising success of the proposed framework on semantic video analysis.
基金supported by the National Natural Science Foundation of China[grant number 41176169]the National Basic Research Program of China[grant number 2011CB309704]
文摘Whether recent Arctic sea ice loss is responsible for recent severe winters over mid-latitude continents has emerged as a major debate among climate scientists owing to short records of observations and large internal variability in mid- and high-latitudes. In this study, the authors divide the evolution of autumn Arctic sea ice extent during 1979–2014 into three epochs, 1979–1986（high）, 1987–2006（moderate）, and 2007–2014（low）, using a regime shift identification method. The authors then compare the associations between autumn Arctic sea ice and winter climate anomalies over central and eastern Eurasia for the three epochs with a focus on extreme events. The results show robust and detectable signals of Arctic sea ice loss in weather and climate over western Siberia and East Asia. Associated with sea ice loss, the latitude（speed） of the jet stream shifts southward（reduces）,the wave extent amplifies, and blocking high events increase over the Ural Mountains, leading to increased frequency of cold air outbreaks extending from central Asia to northeast China. These associations bear a high degree of similarity to the observed atmospheric anomalies during the low sea ice epoch. By contrast, the patterns of atmospheric anomalies for the high sea ice epoch are different from those congruent with sea ice variability, which is related to the persistent negative phase of the Arctic Oscillation.
文摘The impact of temporal variation of rainfall on the relationship between rainfall and catchment response is investigated in a catchment with high temporally variable rainfalls and a high percentage of permeable soils in the southwest of Iran.Twenty-nine storm events are classified into two classes, High Temporal heterogeneous(HT) and Low Temporal heterogeneous(LT) events using the variogram technique and the storm events of each class are analyzed to detect the relationship between Curve Number(CN) and rainfall depth. It is found that there is not a similar correlation between CN values and rainfall depths for both temporally variable classes, and hence, two different responses can be observed in the catchment according to rainfall temporal heterogeneities. For HT events, a complacent behavior is detected in which the CNs decline as rainfall depth increases while a different response, violent behavior, is observed for LT events in which the CNs rise and asymptotically approach a constant value with increasing storm size. This considerable difference between CN-P relationships derived from the two temporally variable classes of rainfall is attributed to the provocation of different runoff generation mechanisms, infiltration-excess and saturation-excess caused by rainfall temporal heterogeneities. Moreover, the results support the validity of variogram technique to classify storm events into two LT and HT classes.
基金Funded by the Planning Project of National Language Committee in the "12th 5-year Plan"(No.YB125-49)the Foundation for Key Program of Ministry of Education,China(No.212167)the Fundamental Research Funds for the Central Universities(No.SWJTU12CX096)
文摘How to quickly and accurately detect new topics from massive data online becomes a main problem of public opinion monitoring in cyberspace. This paperpresents a new event detection method for the current new event detection system, based on sorted subtopic matching algorithm and constructs the entire design framework. In this p^per, the subtopics contained in old topics （or news stories） are sorted in descending order according to their importance to the topic（or news stories）, and form a sorted subtopic sequence. In the process of subtopic matching, subtopic scoring matrix is used to determine whether a new story is reporting a new event. Experimental results show that the sorted subtopic matching model improved the accuracy and effectiveness ofthenew event detection system in cyberspace.
基金funded by the National Science & Technology Pillar Program in the 12th "Five-year Plan" Period,China(2012BAKI9B02)
文摘An algorithm for detecting low-frequency seismic events is developed and applied to the detection of low-frequency events before the 2008 Wenchuan and the 2013 Lushan earthquakes. Continuous vertical-component waveforms of some broadband stations in the few months before the Wenchuan and Lushan earthquakes are processed by applying a bandpass filter in 2- 8Hz,and then converted to envelopes with a smoothing time of 10 s window and a median filter with a 20 min window. As a result,teleseismic,long-period noise and local small earthquakes are removed,the filtered amplitude is obviously larger than that of the noise and lasts for a dozen minutes to several hours during a few days in a few stations before the Wenchuan and Lushan earthquakes,respectively. The waveform and envelope are similar to that of a non-volcanic tremor( NVT). There are suspected NVT before the two earthquakes. Preliminary application demonstrates that this algorithm is potentially useful for extracting NVT signals from continuous seismic waveforms.
文摘Since the implementation of the rules of the supplement and correction of the defective evidences, there are many problems in the practice. The actual investigations and researches also feedback that the judges also have a lot of problems in the face of the definition of the meaning of the defective evidences, the correction application, and the degree restrictions. Behind this reflects the contradiction between the stress of the prosecution organs in the criminal detection and the deepening of the resisting mechanism in the court. And the litigation structure of the ＂division of responsibilities among three authorities＂ and the trial mode of ＂the centralism of the book records of the cases＂ exacerbated this opposition. On the basis of clarifying the origin and the meanings of the defective evidences, the author of this paper analyzes the essence and its harm of the rule. Through the reflections of the problems existing in the practice, the author further defines the two types of the ＂defects＂ that shall not be allowed to correct.
基金Supported by Youth Startup Fund of Second Military Medical University(05QN21)
文摘Objective： To explore the fundamental theory, methods and data of the quality of life （QOL） of soldiers and its influence factors in the first response army. Methods： Totally 215 soldiers in the first response army of a military area in China were inquired by using self-regulating questionnaire and WHOQOL-BREF （Chinese Edition）. Resalts： WHOQOL-BREF had good acceptability, reliability and validity in the first response army. QOL of soldiers in the first response army was middling. The influencing factors of QOL of the soldiers in first army includes self-report health, different areas where the army men come from, different arms of services, whether only child in family. And the difference was statistically significant. Conclusion： WHOQOL-BREF is fit for evaluating the quality of life of soldiers in the first response army. There are differences of the quality of life among the soldiers in the first response army. So we should take appropriate measures to improve the soldiers＇ quality of life.
