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Defense Strategies Against Network Attacks in Cyber-Physical Systems with Analysis Cost Constraint Based on Honeypot Game Model
Get PDFCyber-physical system (CPS) is an advanced system that integrats physical processes, computation and communication resources. The security of cyber-physical systems has become an active research area in recent years. In this paper, we focus on defensive strategies against network attacks in CPS. We introduce both low- and highinteraction honeypots into CPS as a security management tool deliberately designed to be probed, attacked and compromised. In addition, an analysis resource constraint is introduced for the purpose of optimizing defensive strategies against network attacks in CPS. We study the offensive and defensive interactions of CPS and model the offensive and defensive process as an incomplete information game with the assumption that the defender's analysis resource is unknown to the attacker. We prove the existence of several Bayesian-Nash equilibria in the low- and high-interaction honeypot game without analysis cost constraints and obtain the attacker's equilibrium strategy firstly. Then, we take the impact of analysis cost on the capture effect of honeypots into consideration and further optimize the defensive strategy by allocating analysis resource between low- and high-interaction honeypot with resource constraint. Finally, the proposed method is evaluated through numerical simulation and prove to be effective in obtaining the optimal defensive strategy
A High Gain, Noise Cancelling 3.1-10.6 GHz CMOS LNA for UWB Application
Get PDFWith the rapid development of ultra-wideband communications, the design requirements of CMOS radio frequency integrated circuits have become increasingly high. Ultra-wideband (UWB) low noise amplifiers are a key component of the receiver front end. The paper designs a high power gain (S21) and low noise figure (NF) common gate (CG) CMOS UWB low noise amplifier (LNA) with an operating frequency range between 3.1 GHz and 10.6 GHz. The circuit is designed by TSMC 0.13 μm RF CMOS technology. In order to achieve high gain and flat gain as well as low noise figure, the circuit uses many technologies. To improve the input impedance matching at low frequencies, the circuit uses the proposed T-match input network. To decrease the total dissipation, the circuit employs current reused technique. The circuit uses he noise cancelling technique to decreases the NF. The simulation results show a flat S21>20.81 dB, the reverse isolation (S12) less than -48.929 dB, NF less than 2.617 dB, the minimum noise figure (NFmin)=1.721 dB, the input return loss (S11) and output return loss (S22) are both less than -14.933 dB over the frequency range of 3.1 GHz to 10.6 GHz. The proposed UWB LNA consumes 1.548 mW without buffer from a 1.2 V power supply
Design and Performance Comparison of Rotated Y-Shaped Antenna Using Different Metamaterial Surfaces for 5G Mobile Devices
Get PDFIn this paper, a rotated Y-shaped antenna is designed and compared in terms of performance using a conventional and EBG ground planes for future Fifth Generation (5G) cellular communication system. The rotated Y-shaped antenna is designed to transmit at 38 GHz which is one of the most prominent candidate bands for future 5G communication systems. In the design of conventional antenna and metamaterial surfaces (mushroom, slotted), Rogers-5880 substrate having relative permittivity, thickness and loss tangent of 2.2, 0.254 mm, and 0.0009 respectively have been used. The conventional rotated Y-shaped antenna offers a satisfactory wider bandwidth (0.87 GHz) at 38.06 GHz frequency band, which gets further improved using the EBG surfaces (mushroom, slotted) as a ground plane by 1.23 GHz and 0.97 GHz respectively. Similarly, the conventional 5G antenna radiates efficiently with an efficiency of 88% and is increased by using the EBG surfaces (slotted, mushroom-like) to 90% and 94% respectively at the desired resonant frequency band. The conventional antenna yields a bore side gain of 6.59 dB which is further enhanced up to 8.91dB and 7.50 dB by using mushroom-like and slotted EBG surfaces respectively as a ground plane. The proposed rotated Y-shaped antenna and EBG surfaces (mushroom, slotted) are analyzed using the Finite Integration Technique (FIT) employed in Computer Simulation Technology (CST) software. The designed antenna is applicable for future 5G applications
An Application-Oriented Buffer Management Strategy in Opportunistic Networks
Get PDFIn Opportunistic networks (ONs), buffer management is critical to improve the message exchanging efficiency due to the limited storage space and transmission bandwidth at the wireless edge. Current solutions make message scheduling and drop policy based on assumptions that messages can always been forwarded in a single contact, and all node pairs have the same contact rates. However, such ideal assumptions are invalid for realistic mobility traces of hand-held. Recent studies show that the single contact duration is limited and the mobility of nodes is heterogeneous in reality. In this paper, a buffer management strategy based on contact duration and heterogeneous mobility is proposed to improve the efficiency of buffer policy in the practical applications. We mainly focus on the minimization of the total expected delivery delay for all messages in ONs with resource constraints. Using the global network information including existing copies of message in the network, the distribution of pair-wise inter-contact time and contact duration between nodes, we develop a function to compute per-message utility which reflects the contribution of single message to the total expected delivery delay. Messages are scheduled or dropped according to their utilities. Simulation results show that our proposed strategy not only achieves lower delivery delay than mainstream strategies, but also keeps a high delivery ratio and a low network overhead
A Fatigue Damage Model for FRP Composite Laminate Systems Based on Stiffness Reduction
Get PDFThis paper introduces a stiffness reduction based model developed by the authors to characterize accumulative fatigue damage in unidirectional plies and (0/θ/0) composite laminates in fiber reinforced polymer (FRP) composite laminates. The proposed damage detection model is developed based on a damage evolution mechanism, including crack initiation and crack damage progress in matrix, matrix-fiber interface and fibers. Research result demonstrates that the corresponding stiffness of unidirectional composite laminates is reduced as the number of loading cycles progresses. First, three common models in literatures are presented and compared. Tensile viscosity, Young’s modulus and ultimate tensile stress of composites are incorporated as key factors in this model and are modified in accordance with temperature. Four types of FRP composite property parameters, including Carbon Fiber Reinforced Polymer (CFRP), Aramid Fiber Reinforced Polymer (AFRP), Glass Fiber Reinforced Polymer (GFRP), and Basalt Fiber Reinforced Polymer (BFRP), are considered in this research, and a comparative parameter study of FRP unidirectional composite laminates with different off-angle plies using control variate method are discussed. It is concluded that the relationship between the drop in stiffness and the number of cycles also shows three different regions, following the mechanism of damage of FRP composites and the matrix is the dominant factor determined by temperature, while fiber strength is the dominant factor that determine the reliability of composite
A Survey on Digital Image Copy-Move Forgery Localization Using Passive Techniques
Get PDFDigital images can be tampered easily with simple image editing software tools. Therefore, image forensic investigation on the authenticity of digital images’ content is increasingly important. Copy-move is one of the most common types of image forgeries. Thus, an overview of the traditional and the recent copy-move forgery localization methods using passive techniques is presented in this paper. These methods are classified into three types: block-based methods, keypoint-based methods, and deep learning-based methods. In addition, the strengths and weaknesses of these methods are compared and analyzed in robustness and computational cost. Finally, further research directions are discussed
Design of Intelligent Drunk Driving Detection System Based on Internet of Things
No full textIn recent years, with the rapid development of China’s economy and the continuous improvement of people’s living standards, the number of motor vehicles and the number of drivers in the country have grown rapidly. Due to the increase in the number of vehicles and the number of motorists, the traffic accident rate is increasing, causing serious economic losses to society. According to the traffic accident statistics of the Ministry of Communications of China in 2009, more than 300,000 car accidents occurred in the year, most of which were caused by drunk driving. Therefore, this paper proposes a design scheme based on the Internet of Things-based vehicle alcohol detection system. The system uses STM8S003F3 single-chip microcomputer as the main control chip of the system, combined with alcohol sensor MQ-3 circuit, LCD1602 liquid crystal display circuit, buzzer alarm circuit and button circuit to form a complete alcohol detection module hardware system. The main functions of the system are as follows: the alcohol sensor in the car detects the driver’s alcohol concentration value, and displays the value on the LCD screen. The buzzer alarm is exceeded and the information is sent to the traffic police department and the family’s mobile phone through the GPRS module. The system can effectively make up for the shortcomings of traffic police detection, which has certain research significance
Network Electronic Record Management Based on Linked Data
No full textWith the rapid development of e-government, e-commerce and self-media, a large number of electronic network records have been generated on the Internet. How to archive these resources has become a focus of attention in academic circles. Based on the theory of linked data, this paper analyzes the archiving of electronic records, and proposes that the corresponding network electronic records should be collected using the theory of linked data. After the resource description framework and corresponding international standards are utilized to convert the network resources, the electronic network records are stored in common databases to solve the problem of network record archiving management
On Multi-Thread Crawler Optimization for Scalable Text Searching
No full textWeb crawlers are an important part of modern search engines. With the development of the times, data has exploded and humans have entered a “big data era”. For example, Wikipedia carries the knowledge from all over the world, records the real-time news that occurs every day, and provides users with a good database of data, but because of the large amount of data, it puts a lot of pressure on users to search. At present, single-threaded crawling data can no longer meet the requirements of text crawling. In order to improve the performance and program versatility of single-threaded crawlers, a high-speed multi-threaded web crawler is designed to crawl the network hyper-scale text database. Multi-threaded crawling uses multiple threads to process web pages in parallel, combining breadth-first and depth-first algorithms to control web crawling. The practice project is based on the Python language to achieve multi-threaded optimization network hyper-large-scale text database-Wikipedia book crawling method, the project is inspired by the article on the Wikipedia article in the Big Data Digest public number
Computational Modeling of Human Bicuspid Pulmonary Valve Dynamic Deformation in Patients with Tetralogy of Fallot
No full textPulmonary valve stenosis (PVS) is one common right ventricular outflow tract obstruction problem in patients with tetralogy of Fallot (TOF). Congenital bicuspid pulmonary valve (BPV) is a condition of valvular stenosis, and the occurrence of congenital BPV is often associated with TOF. Dynamic computational models of normal pulmonary root (PR) with tri-leaflet and PR with BPV in patients with TOF were developed to investigate the effect of geometric structure of BPV on valve stress and strain distributions. The pulmonary root geometry included valvular leaflets, sinuses, interleaflet triangles and annulus. Mechanical properties of pulmonary valve leaflet were obtained from biaxial testing of human PV leaflet, and characterized by an anisotropic Mooney-Rivlin model. The complete cardiac cycle was simulated to observe valve leaflet dynamic stress/strain behaviors. Our results indicated that stress/strain distribution patterns of normal tri-leaflet pulmonary valve (TPV) and the BPV were different on valve leaflets when the valve was fully open, but they were similar when valves were completely closed. When the valve was fully open, the BPV maximum stress value on the leaflets was 197.2 kPa, which was 94.3% higher than of the normal TPV value (101.5 kPa). During the valve was fully open, the stress distribution in the interleaflet triangles region of the PR was asymmetric in the BPV model compared with that in the TPV model. The geometric orifice area value in the completely opened position of BPV model was reduced 55.6 % from that of the normal PV. Our initial results demonstrated that valve geometrical variations with BPV may be a potential risk factor linked to occurrence of PVS in patients with TOF. Computational models could be a useful tool in identifying possible linkage between valve disease development and biomechanical factors. Large-scale clinical studies are needed to validate these preliminary findings