IGED:Towards Intelligent DDoS Detection Model Using Improved Generalized Entropy and DNN

As the scale of the networks continually expands,the detection of distributed denial of service(DDoS)attacks has become increasingly vital.We propose an intelligent detection model named IGED by using improved generalized entropy and deep neural network(DNN).The initial detection is based on improved generalized entropy to filter out as much normal traffic as possible,thereby reducing data volume.Then the fine detection is based on DNN to perform precise DDoS detection on the filtered suspicious traffic,enhancing the neural network’s generalization capabilities.Experimental results show that the proposed method can efficiently distinguish normal traffic from DDoS traffic.Compared with the benchmark methods,our method reaches 99.9%on low-rate DDoS(LDDoS),flooded DDoS and CICDDoS2019 datasets in terms of both accuracy and efficiency in identifying attack flows while reducing the time by 17%,31%and 8%.

Transformation of hepatitis B serologic markers in babies born to hepatitis B surface antigen positive mothers

AIM:To better understand the clinical significance of hepatitis B seroiogic markers in babies born to hepatitis B surface antigen (HBsAg) positive mothers, the incidence of maternal seroiogic markers of hepatitis B via placenta and its transformation in these babies were investigated. METHODS: Mothers with positive HBsAg were selected in the third trimester of pregnancy. Their babies received immunoprophylaxis with hepatitis B immunoglobulin and hepatitis B vaccine after birth, and were consecutively followed up for hepatitis B seroiogic markers and HBV DNA at birth, mo 1, 4, 7, 12, and 24. RESULTS: Forty-two babies entered the study, including 16 born to hepatitis B e antigen (HBeAg)-positive HBsAg carrier mothers and 26 to HBeAg-negative HBsAg carrier mothers. Apart from four babies born to HBeAg-positive carrier mothers and demonstrated persistent positive HBeAg eventually became HBV carriers, all other babies developed anti-HBs before 12 mo of age. Among the other 12 babies born to HBeAg-positive carrier mothers, HBeAg was detected in 7 at birth, in 4 at mo 1, and in none of them thereafter. No antibody response to the transplacental HBeAg was detected. Among the babies born to HBeAg-negative carrier mothers, anti-HBe was detected 100% at birth and mo 1, in 88.5% at mo 4, in 46.2% at mo 7, in 4.2% at mo 12 and none in mo 24. Among all the immunoprophylaxis-protected babies born to either HBeAg-positive or HBeAg-negative carrier mothers, anti-HBc was detected in 100% at birth, mo 1 and mo 4, in 78.9% at mo 7, in 36.1% at mo 12 and in none at mo 24. CONCLUSION: HBeAg can pass through human placenta from mother to fetus and become undetectable before 4 mo of age, but no antibodies response to the transplacental HBeAg can be detected till mo 24 in the immunoprophylaxis-protected babies. The sole existence of anti-HBe before 1 year of age or anti-HBc before 2 years of age in babies born to HBsAg carrier mothers may simply represent the transplacental maternal antibodies, instead of indicators of HBV infection status.

Construction and analysis of SSH cDNA library of human vascular endothelial cells related to gastrocarcinoma

AIM: To construct subtracted cDNA libraries of human vascular endothelial cells (VECs) related to gastrocarcinoma using suppression substractive hybridization (SSH) and to analyze cDNA libraries of gastrocarcinoma and VECs in Cancer Gene Anatomy Project (CGAP) database.METHODS: Human VECs related to gastric adenocarcinoma and corresponding normal tissue were separated by magnetic beads coupled with antibody CD31 (Dynabeads CD31). A few amount of total RNA were synthesized and amplified by SMARTTM PCR cDNA Synthesis Kit. Then, using SSH and T/A cloning techniques, cDNA fragments of differentially expressed genes in human VECs of gastric adenocarcinoma were inserted into JM109 bacteria. One hundred positive bacteria clones were randomly picked and identified by colony PCR method. To analyze cDNA libraries of gastrocarcinoma and VECs in CGAP database, the tools of Library Finder,cDNA xProfiler, Digital GENE Expression Displayer (DGED),and Digital Differential Display (DDD) were used.RESULTS: Forward and reverse subtraction cDNA libraries of human VECs related to gastrocarcinoma were constructed successfully with SSH and T/A cloning techniques. Analysis of CGAP database indicated that no appropriate library of VECs related to carcinoma was constructed.CONCLUSION: Construction of subtraction cDNA libraries of human VECs related to gastrocarcinoma was successful and necessary, which laid a foundation for screening and cloning new and specific genes of VECs related to gastrocardnoma.

A Novel Fused Phosphorus Heterocycle: 4-(1',2',3',4-Tetrahydro-1, 3, 2-benzodiazaphosphorin-2'-sulfide)-3, 4b, 4a-thiazphosphaphenanthridine Derivative

The first example of fused phosphorus heterocyclic 4-[1-(b-bromoethyl)-4-oxo-3-prop yl-1, 2, 3, 4-tetrahydro-1, 3, 2-benzodiazaphosphorin-2-sulfide]-1, 2, 3, 4, 4a, 4b, 5, 6-octahydro -6-oxo-5-propyl-3, 4b, 4a-thiazphosphaphenanthridine 4a, 2-dioxide was synthesized in excellent yield by refluxing a mixture of 1-(2-bromoethyl)-2, 3-dihydro-3-propyl-1, 3, 2-benzodiazaphos phorin-4(1H)-one 2-oxide with carbon disulfide in benzene in the presence of triethylamine.

Gradient-Based Approach for Fine Registration of Panorama Images

This paper studies the application of gradient-based motion detectiontechniques (i.e., optical flow methods) for registration of adjacent images taken using a hand-heldcamera for the purposes of building a panorama. A general 8-parameter model or a more compact3-parameter model is commonly used for transformation estimation. However, both models areapproximations to the real situation when viewpoint position is not absolutely fixed but includes asmall translation, and thus distortion and blurring are sometimes present in the final registrationresults. This paper proposes a new 5-parameter model that shows better result and has less strictrequirement on good choice of unknown initial parameters. An analysis of disparity recovery rangeand its enlargement using Gaussian filter is also given.

梯度法全视景图像精细配准问题之应用研究

当用普通相机摄取的图像(自然图片)实现全视景浏览时，输入的相邻图像间存在部分重迭，需要对这些图像进行拼接配准。鉴于自然图片可能存在较大的透视和镜头变形，重迭部分较小，以及相邻图像之间由光照变化、暴光不同或镜头特性引起较大的灰度差别，实现高质量自动配准非常困难。图像配准问题也可被视为相机的运动检测。多年来，许多研究人员对如何由光流场检测运动信息进行了大量的研究。采用光流场进行图像配准的方法也称为梯度法。