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Abstract-Due to the worldwide deployment of Long Term Evolution (LTE), the fourth-generation (4G) mobile cellular networking technology, Voice over LTE (VoLTE) [2] has been also well developed in past few years. It exploits packet-switched network to provide call services instead of the traditional circuit- switched telephony. Similar to the Voice over IP (VoIP), VoLTE adopts Session Initiation Protocol...
After a software system is compromised, it can be difficult to understand what vulnerabilities attackers exploited. Any information residing on that machine cannot be trusted as attackers may have tampered with it to cover their tracks. Moreover, even after an exploit is known, it can be difficult to determine whether it has been used to compromise a given machine. Aviation has long-used black boxes...
Hybrid Energy Storage Systems (HESS) has the ability of providing fast and accurate response to second-to-second changes of the grids for keeping the power system uninterrupted and stable. This paper presents an enhanced Corrective Security Constrained Optimal Power Flow (CSCOPF) model by combining the technical merits of different Energy Storage technologies. The proposed HESS can be employed to...
In recent past, Volos et al proposed an image encryption scheme based on true random bits generator in [Signal Processing 93, 1328–1340, 2013]. The TRBG uses two mutually coupled double scroll chaotic systems that are synchronized via complete chaotic synchronization and inverse π-lag synchronization techniques. The numerical simulations demonstrated the effectiveness of chaotic true random bits generator...
Security issues are important concerns of image hashing. A type of image hashing needs to randomly divide a given image into several parts, usually rectangles. However, the security problem arises due to the rectangular shapes. So, we propose a new method which enhances the randomness by dividing the image into zigzag blocks with random walk. Security analyses are provided, and experiments show our...
In this article, it is shown that a large class of truly chaotic Pseudorandom Number Generators can be constructed. The generators are based on iterating Boolean maps, which are computed using balanced Gray codes. The number of such Gray codes gives the size of the class. The construction of such generators is automatic for small number of bits, but remains an open problem when this number becomes...
The integrated energy systems (IESs), composed of deeply interdependent electric power systems (EPSs) and natural-gas systems (NGSs), are expected to play an important role in the transition to low-carbon sustainable energy systems. To facilitate the security assessment of IESs, this paper initially proposes the concept of IES security region. First, The security region of the IES is defined as a...
In the context of voltage stability, this paper describes a fast algorithm that estimates the maximum loadability point (MLP) of a power system from its power flow equations. First it estimates the load level where each generator reaches its reactive limit, this is done using a quadratic curve fitting technique. After that another quadratic curve is used to estimate the MLP. From two power flow solutions,...
This paper presents a multi-objective optimization model based on DC power flow to maximize the active power steady-state security region whilst minimizing the total generation cost. The stochastic and fluctuant nature of wind power is incorporated into the model as well. Regarding the cost of wind power, the concepts involving opportunity costs of wind power shortage and surplus are introduced in...
Distributed DC optimal power flow (DC-OPF) is vulnerable to malicious cyber attacks due to the absence of a control center. In our previous work, we demonstrated a data integrity attack can manipulate the power dispatch result of distributed DC-OPF by compromising the distributed controller on a bus and modifying the information being sent to the neighboring buses. This vulnerability, in turn, could...
Message exchange among vehicles is an integral part of communication in smart cities. Messages are exchanged to inform the other vehicles about emergency situations such as-safety alerts, and location privacy. Due to the usage of an insecure wireless medium, malicious activities in vehicles, i.e., illegal use of the false messages, can astray other vehicles. Security in communication among the vehicles...
Today, most of smart-phones adopt virtual keyboards as input devices for users. However, there are serious secure threats exit such as key-logger attack that leaks key input values of virtual keyboards. Since the smart-phone provides limited virtual keyboards due to its small screen size, it is more vulnerable for such attacks compared to personal computers (PCs). In this paper, we propose a solution...
The paper proposes a concept of an intelligent system for early detection of pre-emergency state in electric power system as an option of preventive operation and emergency control. The main goal of such a system is to early warn and prevent dangerous states and emergency situations before they lead to a system blackout. Consideration is given to a construction principle of systems for security monitoring...
Physical Unclonable Function (PUF) is attracted attention as a countermeasure for imitation electronics. PUF makes unique IDs using the variations when LSI manufacturing. On the other hand, lightweight block ciphers are proposed as security module for IoT devices. This study verifies the feasibility of security module using a lightweight block cipher (TWINE) and PUF.
This paper investigates the value of nodal information of power systems in real-time. It is a fact that real-time security assessment of the power system requires nodal scheduling information of generating units, however, the value of this information from a market aspect is seldom discussed. In other words, precise schedules help the system operator not only assess the system security, but also estimate...
In the present research, plasma jets form from Joule heating and ablation of a radial foil (∼15 μm thin disk) using a pulsed power generator (COBRA) with 1 MA peak current and 100 ns rise time. We study the effects on jet dynamics resulting from varying an applied uniform axial magnetic field (Bz) from 0 to 1.8 T. We empirically observe a disruption of the plasma jet collimation. The critical Bz for...
In order to overcome a number of difficulties detected on the Brazilian electricity market this paper proposes and tests a bid based short-term market. To simulate the behavior of the hydros in this new market, it was implemented an Agent-Based Model - ABM using the reinforcement Q-Learning algorithm, Simulated Annealing, and linear programming. In the simulations we used real data from the Brazilian...
The impact of coordinated malicious attacks may be dramatically severe and may yield a wide area blackout. A preventive measure is enhancing the infrastructure through investment. Due to limited budget, a decision making is required to select the best possible options, considering cost/benefit ratio. We designed a time-step simulation framework representing the evolution of post-contingency failures...
Complex programmable logic device (CPLD) can be reconfigured to perform any desired application, the main theme of this paper was to reconfigure the CPLD which performs addition operation after detecting the given sequence for the choice of implementing security for the particular operation just like password protection. It mainly focused on designing an adder which performs its addition operation...
Linear layers are crucial building blocks in the design of lightweight block ciphers, since they perform the dual task of providing the much needed diffusion, while also ensuring minimal hardware cost for implementation. Although a number of lightweight block ciphers with parsimoniously designed linear layers have been proposed in cryptographic literature, there is limited work on generic construction...
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