针对深度学习方法运用于入侵检测时需要大量标注数据集和难以实时检测的缺陷,利用网络流量中正常数据多于异常数据的一般规律,提出一种结合集成K-means聚类和自编码器的EKM-AE(ensemble K-means and autoencoder)入侵检测方法.首先通过...针对深度学习方法运用于入侵检测时需要大量标注数据集和难以实时检测的缺陷,利用网络流量中正常数据多于异常数据的一般规律,提出一种结合集成K-means聚类和自编码器的EKM-AE(ensemble K-means and autoencoder)入侵检测方法.首先通过集成K-means聚类从实时抓取的网络流量中得出正常样例,用于训练自编码器,然后由完成训练的自编码器执行入侵检测.在虚拟局域网主机环境下进行了入侵检测实验,结果表明,在绝大多数实际应用场景(正常流量多于异常流量)下该方法具有良好的检测性能,且具有全过程无监督、可实时在线检测的优点,对主机网络安全有良好的提升作用.展开更多
In the paper, we propose a surface wave suppression method in time-frequency domain based on the wavelet transform, considering the characteristic difference of polarization attributes, amplitude energy and apparent v...In the paper, we propose a surface wave suppression method in time-frequency domain based on the wavelet transform, considering the characteristic difference of polarization attributes, amplitude energy and apparent velocity between the effective signals and strong surface waves. First, we use the proposed method to obtain time-frequency spectra of seismic signals by using the wavelet transform and calculate the instantaneous polarizability at each point based on instantaneous polarization analysis. Then, we separate the surface wave area from the signal area based on the surface-wave apparent velocity and the average energy of the signal. Finally, we combine the polarizability, energy, and frequency characteristic to identify and suppress the signal noise. Model and field data are used to test the proposed filtering method.展开更多
Hydrodynamic cavitation is a new technique in wastewater treatment processes. The degradation of Rbodamine B was studied on a 220 liters hydrodynamic cavitation setup using multiple hole orifice plates in this paper. ...Hydrodynamic cavitation is a new technique in wastewater treatment processes. The degradation of Rbodamine B was studied on a 220 liters hydrodynamic cavitation setup using multiple hole orifice plates in this paper. The experimental results showed that Rhodamine B was really decomposed by hydrodynamic cavitation. Some factors influencing degradation effect i.e. geometric parameters and operation conditions also were discussed. It was concluded there was the optimal ratio of total area of holes to crosssectional area of the pipe and the rate constant increased with a reduction in the value of the modified cavitional number.展开更多
Background Bladder urothelial cancer has been diagnosed at an increasing rate among young adults in China while the clinical outcomes remain highly controversial. To optimize the management of young patients with blad...Background Bladder urothelial cancer has been diagnosed at an increasing rate among young adults in China while the clinical outcomes remain highly controversial. To optimize the management of young patients with bladder cancer, we examined whether bladder urothelial cancer in young patients behaved differently from that in the elder patients. Methods From 1994 to 2008, a database of bladder urothelial cancer patients at a major tertiary medical center was retrospectively reviewed. The clinical and pathological parameters of patients who were less than 40 years of age and a series of patients older than 40 years of age as the control group during the same period were compared. A survival analysis was performed using the Kaptan-Meier method and log-rank test, and Cox regression was performed to identify clinical parameters that affected the clinic outcomes. Results Young bladder cancer patients had a lower male-to-female ratio and were less likely to have advanced stages and high-grade cancers at the initial diagnosis. Tumors in young bladder cancer patients tended to be less multifocal at diagnosis. In addition, young patients had a lower recurrence rate and longer recurrence interval than older patients. The Kaplan-Meier curve and Log-rank test showed that young patients had significantly better cancer specific survival than old patients. The univariate and multivariate Cox regression analysis revealed that tumor grade is the sole predictor for tumor recurrence in young patients. Conclusions Young patients with bladder cancer have favorable pathological features and clinical outcomes than older patients. These findinqs ar.que for more conservative management approaches for young patients with bladder cancer.展开更多
文摘针对深度学习方法运用于入侵检测时需要大量标注数据集和难以实时检测的缺陷,利用网络流量中正常数据多于异常数据的一般规律,提出一种结合集成K-means聚类和自编码器的EKM-AE(ensemble K-means and autoencoder)入侵检测方法.首先通过集成K-means聚类从实时抓取的网络流量中得出正常样例,用于训练自编码器,然后由完成训练的自编码器执行入侵检测.在虚拟局域网主机环境下进行了入侵检测实验,结果表明,在绝大多数实际应用场景(正常流量多于异常流量)下该方法具有良好的检测性能,且具有全过程无监督、可实时在线检测的优点,对主机网络安全有良好的提升作用.
基金supported by the National Science and Technology Major Project(No.2011ZX05002-004-002)the National Natural Science Foundation of China(No.41304111 and 41704132)+3 种基金Key Project of Science&Technology Department of Sichuan Province(No.2016JY0200)Natural Science project of Education Department of Sichuan Province(Nos.17ZA0025,16ZB0101 and 18CZ0008)the Sichuan Provincial Youth Science&Technology Innovative Research Group Fund(No.2016TD0023)the Cultivating Program of Excellent Innovation Team of Chengdu University of Technology(No.KYTD201410)
文摘In the paper, we propose a surface wave suppression method in time-frequency domain based on the wavelet transform, considering the characteristic difference of polarization attributes, amplitude energy and apparent velocity between the effective signals and strong surface waves. First, we use the proposed method to obtain time-frequency spectra of seismic signals by using the wavelet transform and calculate the instantaneous polarizability at each point based on instantaneous polarization analysis. Then, we separate the surface wave area from the signal area based on the surface-wave apparent velocity and the average energy of the signal. Finally, we combine the polarizability, energy, and frequency characteristic to identify and suppress the signal noise. Model and field data are used to test the proposed filtering method.
文摘Hydrodynamic cavitation is a new technique in wastewater treatment processes. The degradation of Rbodamine B was studied on a 220 liters hydrodynamic cavitation setup using multiple hole orifice plates in this paper. The experimental results showed that Rhodamine B was really decomposed by hydrodynamic cavitation. Some factors influencing degradation effect i.e. geometric parameters and operation conditions also were discussed. It was concluded there was the optimal ratio of total area of holes to crosssectional area of the pipe and the rate constant increased with a reduction in the value of the modified cavitional number.
文摘Background Bladder urothelial cancer has been diagnosed at an increasing rate among young adults in China while the clinical outcomes remain highly controversial. To optimize the management of young patients with bladder cancer, we examined whether bladder urothelial cancer in young patients behaved differently from that in the elder patients. Methods From 1994 to 2008, a database of bladder urothelial cancer patients at a major tertiary medical center was retrospectively reviewed. The clinical and pathological parameters of patients who were less than 40 years of age and a series of patients older than 40 years of age as the control group during the same period were compared. A survival analysis was performed using the Kaptan-Meier method and log-rank test, and Cox regression was performed to identify clinical parameters that affected the clinic outcomes. Results Young bladder cancer patients had a lower male-to-female ratio and were less likely to have advanced stages and high-grade cancers at the initial diagnosis. Tumors in young bladder cancer patients tended to be less multifocal at diagnosis. In addition, young patients had a lower recurrence rate and longer recurrence interval than older patients. The Kaplan-Meier curve and Log-rank test showed that young patients had significantly better cancer specific survival than old patients. The univariate and multivariate Cox regression analysis revealed that tumor grade is the sole predictor for tumor recurrence in young patients. Conclusions Young patients with bladder cancer have favorable pathological features and clinical outcomes than older patients. These findinqs ar.que for more conservative management approaches for young patients with bladder cancer.
