由于传统离群点检测方法未对离群点进行判定,从而导致出现了检测速度慢、检测误差大的问题,为此提出一种海量不确定数据集中离群点快速检测的方法。优先判定出不确定数据集中的离群点,利用点排序识别聚类结构(Ordering points to identi...由于传统离群点检测方法未对离群点进行判定,从而导致出现了检测速度慢、检测误差大的问题,为此提出一种海量不确定数据集中离群点快速检测的方法。优先判定出不确定数据集中的离群点,利用点排序识别聚类结构(Ordering points to identify the clustering structure)算法完成,确定待检测离群点所需参数,计算出离群点的离群属性,根据离群属性计算结果,引入邻域密度构建离群点快速检测模型,设定模型中离群点检测阈值,实现不确定数据集中离群点的快速检测。由仿真结果得出,与传统检测方法相比,提出的方法算法运行耗时降低了50%以上,离群点的判定准确度更高,漏检、误检率大大降低,实现了离群点精度高、速度快的检测,对数据挖掘与预处理有显著的实践意义。展开更多
An exogenous avian leukosis virus (ALV) strain SDAU09C1 was isolated in DF-1 cells from one of 240 imported 1-day-old white meat-type grand parent breeder chicks. Inoculation of SDAU09C1 in ALV-free chickens induced a...An exogenous avian leukosis virus (ALV) strain SDAU09C1 was isolated in DF-1 cells from one of 240 imported 1-day-old white meat-type grand parent breeder chicks. Inoculation of SDAU09C1 in ALV-free chickens induced antibody reactions specific to subgroup A or B. But gp85 amino acid sequence comparisons indicated that SDAU09C1 fell into subgroup A; it had homology of 88.8%-90.3% to 6 reference strains of subgroup A, much higher compared to other subgroups including subgroup B. This is the first report for ALV of subgroup A isolated from imported breeders.展开更多
Quadratic-field cryptosystem is a cryptosystem built from discrete logarithm problem in ideal class groups of quadratic fields(CL-DLP). The problem on digital signature scheme based on ideal class groups of quadratic ...Quadratic-field cryptosystem is a cryptosystem built from discrete logarithm problem in ideal class groups of quadratic fields(CL-DLP). The problem on digital signature scheme based on ideal class groups of quadratic fields remained open, because of the difficulty of computing class numbers of quadratic fields. In this paper, according to our researches on quadratic fields, we construct the first digital signature scheme in ideal class groups of quadratic fields, using q as modulus, which denotes the prime divisors of ideal class numbers of quadratic fields. Security of the new signature scheme is based fully on CL-DLP. This paper also investigates realization of the scheme, and proposes the concrete technique. In addition, the technique introduced in the paper can be utilized to realize signature schemes of other kinds.展开更多
Two types of the dual mode-locked fiber lasers for asynchronous absolute distance measurement are investigated, The lasers are linear and ring cavity with repetition rate of 70 MHz and 100 MHz, respectively. The group...Two types of the dual mode-locked fiber lasers for asynchronous absolute distance measurement are investigated, The lasers are linear and ring cavity with repetition rate of 70 MHz and 100 MHz, respectively. The group velocity dispersion is not compensated in the first type of the lasers, while the others are fully done. The timing jitter with the Allan deviation below averaging time of 0.2 s during the distance measurement for around 1 m of both types of lasers were 2.5 ps with 600 nm and 1.6 ps with 200 nm. We concluded that the phase noise resulted from the intra-cavity dispersion is the main contribution for the uncertainty of the ranging in these two types of the lasers.展开更多
It is Thurston's result that for a hyperbolic knot K in S^3, almost all Dehn fillings on its complement result in hyperbolic 3-manifolds except some exceptional cases. So almost all produced 3-manifolds have the s...It is Thurston's result that for a hyperbolic knot K in S^3, almost all Dehn fillings on its complement result in hyperbolic 3-manifolds except some exceptional cases. So almost all produced 3-manifolds have the same geometry. It is known that its complement in S^3, denoted by E(K), admits a Heegaard splitting. Then it is expected that there is a similar result on Heegaard distance for Dehn fillings. In this paper, Dehn fillings on genus two Heegaard splittings are studied. More precisely, we prove that if the distance of a given genus two Heegaard splitting of E(K) is at least 3, then for any two degenerating slopes on ?E(K), there is a universal bound of their distance in the curve complex of ?E(K).展开更多
Dual clustering performs object clustering in both spatial and non-spatial domains that cannot be dealt with well by traditional clustering methods.However,recent dual clustering research has often omitted spatial out...Dual clustering performs object clustering in both spatial and non-spatial domains that cannot be dealt with well by traditional clustering methods.However,recent dual clustering research has often omitted spatial outliers,subjectively determined the weights of hybrid distance measures,and produced diverse clustering results.In this study,we first redefined the dual clustering problem and related concepts to highlight the clustering criteria.We then presented a self-organizing dual clustering algorithm (SDC) based on the self-organizing feature map and certain spatial analysis operations,including the Voronoi diagram and polygon aggregation and amalgamation.The algorithm employs a hybrid distance measure that combines geometric distance and non-spatial similarity,while the clustering spectrum analysis helps to determine the weight of non-spatial similarity in the measure.A case study was conducted on a spatial database of urban land price samples in Wuhan,China.SDC detected spatial outliers and clustered the points into spatially connective and attributively homogenous sub-groups.In particular,SDC revealed zonal areas that describe the actual distribution of land prices but were not demonstrated by other methods.SDC reduced the subjectivity in dual clustering.展开更多
文摘由于传统离群点检测方法未对离群点进行判定,从而导致出现了检测速度慢、检测误差大的问题,为此提出一种海量不确定数据集中离群点快速检测的方法。优先判定出不确定数据集中的离群点,利用点排序识别聚类结构(Ordering points to identify the clustering structure)算法完成,确定待检测离群点所需参数,计算出离群点的离群属性,根据离群属性计算结果,引入邻域密度构建离群点快速检测模型,设定模型中离群点检测阈值,实现不确定数据集中离群点的快速检测。由仿真结果得出,与传统检测方法相比,提出的方法算法运行耗时降低了50%以上,离群点的判定准确度更高,漏检、误检率大大降低,实现了离群点精度高、速度快的检测,对数据挖掘与预处理有显著的实践意义。
基金supported by a grant from Shandong province and a grant (200803019) from the Ministry of Agriculturesupported by a grant from Shandong province and a grant (20080019) from the Ministry of Agriculture
文摘An exogenous avian leukosis virus (ALV) strain SDAU09C1 was isolated in DF-1 cells from one of 240 imported 1-day-old white meat-type grand parent breeder chicks. Inoculation of SDAU09C1 in ALV-free chickens induced antibody reactions specific to subgroup A or B. But gp85 amino acid sequence comparisons indicated that SDAU09C1 fell into subgroup A; it had homology of 88.8%-90.3% to 6 reference strains of subgroup A, much higher compared to other subgroups including subgroup B. This is the first report for ALV of subgroup A isolated from imported breeders.
文摘Quadratic-field cryptosystem is a cryptosystem built from discrete logarithm problem in ideal class groups of quadratic fields(CL-DLP). The problem on digital signature scheme based on ideal class groups of quadratic fields remained open, because of the difficulty of computing class numbers of quadratic fields. In this paper, according to our researches on quadratic fields, we construct the first digital signature scheme in ideal class groups of quadratic fields, using q as modulus, which denotes the prime divisors of ideal class numbers of quadratic fields. Security of the new signature scheme is based fully on CL-DLP. This paper also investigates realization of the scheme, and proposes the concrete technique. In addition, the technique introduced in the paper can be utilized to realize signature schemes of other kinds.
文摘Two types of the dual mode-locked fiber lasers for asynchronous absolute distance measurement are investigated, The lasers are linear and ring cavity with repetition rate of 70 MHz and 100 MHz, respectively. The group velocity dispersion is not compensated in the first type of the lasers, while the others are fully done. The timing jitter with the Allan deviation below averaging time of 0.2 s during the distance measurement for around 1 m of both types of lasers were 2.5 ps with 600 nm and 1.6 ps with 200 nm. We concluded that the phase noise resulted from the intra-cavity dispersion is the main contribution for the uncertainty of the ranging in these two types of the lasers.
基金supported by National Natural Science Foundation of China(Grant Nos.11371094,11571110 and 11601065)
文摘It is Thurston's result that for a hyperbolic knot K in S^3, almost all Dehn fillings on its complement result in hyperbolic 3-manifolds except some exceptional cases. So almost all produced 3-manifolds have the same geometry. It is known that its complement in S^3, denoted by E(K), admits a Heegaard splitting. Then it is expected that there is a similar result on Heegaard distance for Dehn fillings. In this paper, Dehn fillings on genus two Heegaard splittings are studied. More precisely, we prove that if the distance of a given genus two Heegaard splitting of E(K) is at least 3, then for any two degenerating slopes on ?E(K), there is a universal bound of their distance in the curve complex of ?E(K).
基金supported by the National Natural Science Foundation of China(Grant No.40901188)the Key Laboratory of Geo-informatics of the State Bureau of Surveying and Mapping(Grant No.200906)the Fundamental Research Funds for the Central Universities(Grant No.4082002)
文摘Dual clustering performs object clustering in both spatial and non-spatial domains that cannot be dealt with well by traditional clustering methods.However,recent dual clustering research has often omitted spatial outliers,subjectively determined the weights of hybrid distance measures,and produced diverse clustering results.In this study,we first redefined the dual clustering problem and related concepts to highlight the clustering criteria.We then presented a self-organizing dual clustering algorithm (SDC) based on the self-organizing feature map and certain spatial analysis operations,including the Voronoi diagram and polygon aggregation and amalgamation.The algorithm employs a hybrid distance measure that combines geometric distance and non-spatial similarity,while the clustering spectrum analysis helps to determine the weight of non-spatial similarity in the measure.A case study was conducted on a spatial database of urban land price samples in Wuhan,China.SDC detected spatial outliers and clustered the points into spatially connective and attributively homogenous sub-groups.In particular,SDC revealed zonal areas that describe the actual distribution of land prices but were not demonstrated by other methods.SDC reduced the subjectivity in dual clustering.
