Detecting Malicious Social Robots with Generative Adversarial Networks

( Bin Wu ),( Le Liu ),( Zhengge Dai ),( Xiujuan Wang ),( Kangfeng Zheng ) 한국인터넷정보학회 2019 KSII Transactions on Internet and Information Syst Vol.13 No.11

Malicious social robots, which are disseminators of malicious information on social networks, seriously affect information security and network environments. The detection of malicious social robots is a hot topic and a significant concern for researchers. A method based on classification has been widely used for social robot detection. However, this method of classification is limited by an unbalanced data set in which legitimate, negative samples outnumber malicious robots (positive samples), which leads to unsatisfactory detection results. This paper proposes the use of generative adversarial networks (GANs) to extend the unbalanced data sets before training classifiers to improve the detection of social robots. Five popular oversampling algorithms were compared in the experiments, and the effects of imbalance degree and the expansion ratio of the original data on oversampling were studied. The experimental results showed that the proposed method achieved better detection performance compared with other algorithms in terms of the F1 measure. The GAN method also performed well when the imbalance degree was smaller than 15%.

Stability Analysis for Time-delay Systems with Nonlinear Disturbances via New Generalized Integral Inequalities

Bin Wu,Chang-Long Wang,Yong-Jiang Hu,Xiao-Lin Ma 제어·로봇·시스템학회 2018 International Journal of Control, Automation, and Vol.16 No.6

This paper represents a novel less conservative stability criterion for time-delay systems with nonlinear disturbances. The main purpose is to obtain larger upper bound of the time-varying delay. A suitable Lyapunov- Krasovskii functional (LKF) with triple integral terms is constructed. Then, two new generalized double integral (GDI) inequalities are proposed which encompass Wirtinger-based double inequality as a special case. A simple case of the proposed GDI inequality is utilized to estimate double integral terms in the time derivative of the constructed LKF. Further, an improved delay-dependent stability criterion is derived in the form of linear matrix inequalities (LMIs). Finally, some numerical examples are given to illustrate the improvement of the proposed criteria.

Model updating with constrained unscented Kalman filter for hybrid testing

Bin Wu,Tao Wang 국제구조공학회 2014 Smart Structures and Systems, An International Jou Vol.14 No.6

The unscented Kalman filter (UKF) has been developed for nonlinear model parametric identification, and it assumes that the model parameters are symmetrically distributed about their mean values without any constrains. However, the parameters in many applications are confined within certain ranges to make sense physically. In this paper, a constrained unscented Kalman filter (CUKF) algorithm is proposed to improve accuracy of numerical substructure modeling in hybrid testing. During hybrid testing, the numerical models of numerical substructures which are assumed identical to the physical substructures are updated online with the CUKF approach based on the measurement data from physical substructures. The CUKF method adopts sigma points (i.e., sample points) projecting strategy, with which the positions and weights of sigma points violating constraints are modified. The effectiveness of the proposed hybrid testing method is verified by pure numerical simulation and real-time as well as slower hybrid tests with nonlinear specimens. The results show that the new method has better accuracy compared to conventional hybrid testing with fixed numerical model and hybrid testing based on model updating with UKF.

A management strategy for solar panel - battery - super capacitor hybrid energy system in solar car

Bin Wu,Fang Zhuo,Fei Long,Weiwei Gu,Yang Qing,YanQin Liu 전력전자학회 2011 ICPE(ISPE)논문집 Vol.2011 No.5

This paper presents an application of solar energy - battery - super-capacitor hybrid energy storage system in solar electric vehicles. The key point is the proposed energy management control algorithm. The entire system consists of a solar panel, a boost converter, a battery, a super capacitor, a bi-directional DC/DC converter, and a brushless DC motor. This paper gives the details of the control strategy to cooperate the three energy sources or storage devices: solar panel, battery and super capacitor. A hysteretic control algorithm for battery charging by solar panel is given. A novel control method for bi-directional DC/DC is proposed to keep the battery discharging current within a certain limit and make full use of super capacitor. The switching transient between super-capacitor charging mode and discharging mode is also presented. Both simulation and experimental results demonstrate the effectiveness of the proposed strategy.

Identification of drought response genes in Zygophyllum xanthoxylum by suppression subtractive hybridization

Bin Wu,Xiaohua Su 한국식물학회 2016 Journal of Plant Biology Vol.59 No.4

Drought is an important abiotic stress that seriously limits plant growth and crop productivity in some regions of the world. Zygophyllum xanthoxylum, a succulent xerophyte species with excellent adaptability to adverse arid environments, is an excellent model system for the study of the molecular mechanisms behind drought tolerance in xerophytic species. To better understand the molecular basis of Z. xanthoxylum responses to drought stress and to isolate drought tolerance-related genes from Z. xanthoxylum, we constructed a cDNA library from Z. xanthoxylum and screened the library for stress-related genes by PCR-based suppression subtractive hybridization (SSH). A total of 637 expressed sequence tags were generated by sequencing 672 randomly selected clones, resulting in the identification of 338 unigenes comprising 77 contigs and 261 singlets. The unigenes were assigned to 13 functional categories, such as metabolism, disease- or defense-related genes and energyrelated gene. In addition, we analyzed the expression patterns of 24 genes associated with drought stress-responsive pathways by real-time RT-PCR. The results indicated that osmolyte biosynthesis genes, reactive oxygen scavengers, transporters, signaling components and transcription factors play important roles in drought stress responses. This study provides a valuable resource for studying the drought tolerance mechanism of this xerophytic plant species.

Ursolic Acid-induced Apoptosis in K562 Cells Involving Upregulation of PTEN Gene Expression and Inactivation of the PI3K/Akt Pathway

Bin Wu,Zhuo-gang Liu,Xu Wang,Zuo-fei Chi,Rong Hu,Rong Zhang,Wei Yang 대한약학회 2012 Archives of Pharmacal Research Vol.35 No.3

Ursolic acid (UA), a pentacyclic triterpenoid derived from a variety of medicinal plants, exhibits potent anticancer activity against many types of cancer cells. However, the anticancer mechanism of UA is not clearly understood. Suppression of phosphatase and a tensin homolog deleted on chromosome 10 (PTEN) gene expression leading to activation of the phosphatidylinositol-3-OH kinase (PI3K)/Akt pathway has been observed in many cancers including leukemia, making the PTEN gene and PI3K/Akt pathway a central target for cancer therapy. Here, we demonstrated that UA was able to inhibit growth, induce apoptosis in a human chronic myelogenous leukemia cell line (K562 cells) via upregulation of PTEN gene expression, inhibit Akt kinase activity, change mitochondrial transmembrane potential and reduce the release of cytochrome c and the activity of caspases. These results suggest that UA may elicit its strong antitumor effects via upregulation of the PTEN gene and inhibition of the PI3K/Akt pathway.

The 2018 US-Korea FTA Revision: From the US Perspective

Binwu Qin,Rajesh Sharma 이준국제법연구원 2019 Journal of East Asia and International Law Vol.12 No.1

HSP70 attenuates compression-induced apoptosis of nucleus pulposus cells by suppressing mitochondrial fission via upregulating the expression of SIRT3

Hu Binwu,Wang Peng,Zhang Shuo,Liu Weijian,Lv Xiao,Shi Deyao,Zhao Lei,Liu Hongjian,Wang Baichuan,Chen Songfeng,Shao Zengwu 생화학분자생물학회 2022 Experimental and molecular medicine Vol.54 No.-

Compression-induced apoptosis of nucleus pulposus (NP) cells plays a pivotal role in the pathogenesis of intervertebral disc degeneration (IVDD). Recent studies have shown that the dysregulation of mitochondrial fission and fusion is implicated in the pathogenesis of a variety of diseases. However, its role in and regulatory effects on compression-induced apoptosis of NP cells have not yet been fully elucidated. Heat shock protein 70 (HSP70) is a major cytoprotective heat shock protein, but its physiological role in IVDD, especially its effect on mitochondrial fission and fusion, is still unknown. Herein, we found that compression could induce mitochondrial fission, which ultimately trigger apoptosis of NP cells via the mitochondrial apoptotic pathway. In addition, we identified the cytoprotective effects of HSP70 on NP cells, and we found that promoting the expression of HSP70 could protect NP cells from abnormal mechanical loading in vitro and in vivo. Finally, we showed that HSP70 inhibited compression-induced mitochondrial fission by promoting SIRT3 expression, thereby attenuating mitochondrial dysfunction and the production of reactive oxygen species and ultimately inhibiting the mitochondrial apoptotic pathway in NP cells. In conclusion, our results demonstrated that HSP70 could attenuate compression-induced apoptosis of NP cells by suppressing mitochondrial fission via upregulating SIRT3 expression. Promoting the expression of HSP70 might be a novel strategy for the treatment of IVDD.

Using Genetic Algorithm for Optimal Security Hardening in Risk Flow Attack Graph

( Fangfang Dai ),( Kangfeng Zheng ),( Binwu ),( Shoushan Luo ) 한국인터넷정보학회 2015 KSII Transactions on Internet and Information Syst Vol.9 No.5

Network environment has been under constant threat from both malicious attackers and inherent vulnerabilities of network infrastructure. Existence of such threats calls for exhaustive vulnerability analyzing to guarantee a secure system. However, due to the diversity of security hazards, analysts have to select from massive alternative hardening strategies, which is laborious and time-consuming. In this paper, we develop an approach to seek for possible hardening strategies and prioritize them to help security analysts to handle the optimal ones. In particular, we apply a Risk Flow Attack Graph (RFAG) to represent network situation and attack scenarios, and analyze them to measure network risk. We also employ a multi-objective genetic algorithm to infer the priority of hardening strategies automatically. Finally, we present some numerical results to show the performance of prioritizing strategies by network risk and hardening cost and illustrate the application of optimal hardening strategy set in typical cases. Our novel approach provides a promising new direction for network and vulnerability analysis to take proper precautions to reduce network risk.

FOURIER TRANSFORM AND Lp-MIXED PROJECTION BODIES

Lijuan Liu,Wei Wang,Binwu He 대한수학회 2010 대한수학회보 Vol.47 No.5

In this paper we define the Lp-mixed curvature function of a convex body. We develop a formula connection the support function of Lp-mixed projection body with Fourier transform of the Lp-mixed curvature function. Using this formula we solve an analog of the Shephard projection problem for Lp-mixed projection bodies.