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A UML Profile for Security and Code Generation
No full textRecently, many research studies have suggested the integration of safety engineering at an early stage of modeling and system development using Model-Driven Architecture (MDA). This concept consists in deploying the UML (Unified Modeling Language) standard as a principal metamodel for the abstractions of different systems. To our knowledge, most of this work has focused on integrating security requirements after the implementation phase without taking them into account when designing systems. In this work, we focused our efforts on non-functional aspects such as the business logic layer, data flow monitoring, and high-quality service delivery. Practically, we have proposed a new UML profile for security integration and code generation for the Java platform. Therefore, the security properties will be described by a UML profile and the OCL language to verify the requirements of confidentiality, authorization, availability, data integrity, and data encryption. Finally, the source code such as the application security configuration, the method signatures and their bodies, the persistent entities and the security controllers generated from sequence diagram of system’s internal behavior after its extension with this profile and applying a set of transformations
A Defense-in-depth Cybersecurity for Smart Substations
No full textThe increase of cyber-attacks on industrial and power systems in the recent years make the cybersecurity of supervisory control and data acquisition and substation automation systems a high important engineering issue. This paper proposes a defense in depth cybersecurity solution for smart substations in different layers of the substation automation system. In fact, it presents possible vulnerabilities in the substation automation system and propose a multiple layer solution based on best practice in cyber security such as the hardening of devices, whitelisting, network configuration, network segmentation, role-based account management and cyber security management and deployement
A Miniature BroadBand Microstrip Antenna for LTE, Wi-Fi and WiMAX Applications
No full textA Compact microstrip antenna with rectangular slotted radiating element has been developed. Four slots have been introduced on the radiating element with the use of a partial ground plane and a wideband response has been obtained. The bandwidth of the proposed antenna is 1.7 GHz with a percentage bandwidth of 71%. A low-cost dielectric (FR4_EPOXY) has been considered in the development of the proposed antenna. The obtained frequency band is from 1.9 GHz to 3.6 GHz. To investigate the robustness of our modelled antenna the simulation process has been carried out using two different solvers (Finite Element Method and Finite Integration Technique). In addition, the designed antenna was realized and these results were compared with those of the simulation. The proposed antenna is suitable for many LTE bands {1, 3, 7… 38, 40} broadly deployed in European, South American, Asian, and African countries, Wi-Fi (2.4 GHz), and WiMAX technology (3.5 GHz)
Elliptic Curve Cryptography Based Data Transmission against Blackhole Attack in MANET
No full textMobile nodes roaming around in the hostile environment of mobile adhoc network (MANET) play the role of router as well as terminal. While acting as a router, a node needs to choose a reliable routing protocol. Besides, an encryption algorithm is needed to secure data to be conveyed through the unfriendly atmosphere while acting as a terminal. We have implemented Elliptic Curve Cryptography (ECC) along with Adhoc On Demand Multipath Distance Vector (AOMDV) routing protocol to secure data transmission against blackhole attack in a MANET. ECC, a public key cryptography that works on discrete logarithm problem with a much smaller key size, has been used to encrypt data packets at source node before transmission. We have used AOMDV, a reliable routing protocol compared to its parent protocol, Adhoc On Demand Distance Vector (AODV), with a multipath extension, for routing. The encrypted packets transferring between nodes via AOMDV, has been proved secured against blackhole attack. The performance of the secured protocol has been analyzed in terms of different performance metrics and in terms of varying number of blackhole attacker nodes
Extraction of Water-body Area from High-Resolution Landsat Imagery
No full textExtraction of water bodies from satellite imagery has been broadly explored in the current decade. So many techniques were involved in detecting of the surface water bodies from satellite data. To detect and extracting of surface water body changes in Nagarjuna Sagar Reservoir, Andhra Pradesh from the period 1989 to 2017, were calculated using Landsat-5 TM, and Landsat-8 OLI data. Unsupervised classification and spectral water indexing methods, including the Normalized Difference Vegetation Index (NDVI), Normalized Difference Moisture Index (NDMI), Normalized Difference Water Index (NDWI), and Modified Normalized Difference Water Index (MNDWI), were used to detect and extraction of the surface water body from satellite data. Instead of all index methods, the MNDWI was performed better results. The Reservoir water area was extracted using spectral water indexing methods (NDVI, NDWI, MNDWI, and NDMI) in 1989, 1997, 2007, and 2017. The shoreline shrunk in the twenty-eight-year duration of images. The Reservoir Nagarjuna Sagar lost nearly around one-fourth of its surface water area compared to 1989. However, the Reservoir has a critical position in recent years due to changes in surface water and getting higher mud and sand. Maximum water surface area of the Reservoir will lose if such decreasing tendency follows continuously
Detection and Monitoring Intra/Inter Crosstalk in Optical Network on Chip
No full textMultiprocessor system-on-chip (MPSoC) has become an attractive solution for improving the performance of single chip in objective to satisfy the performance growing exponentially of the computer applications as multimedia applications. However, the communication between the different processors’ cores presents the first challenge front the high performance of MPSoC. Besides, Network on Chip (NoC) is among the most prominent solution for handling the on-chip communication. Besides, NoC potential limited by physical limitation, power consumption, latency and bandwidth in the both case: increasing data exchange or scalability of Multicores. Optical communication offers a wider bandwidth and lower power consumption, based on, a new technology named Optical Network-on-Chip (ONoC) has been introduced in MPSoC. However, ONoC components induce the crosstalk noise in the network on both forms intra/inter crosstalk. This serious problem deteriorates the quality of signals and degrades network performance. As a result, detection and monitoring the impairments becoming a challenge to keep the performance in the ONoC. In this article, we propose a new system to detect and monitor the crosstalk noise in ONoC. Particularly, we present an analytic model of intra/inter crosstalk at the optical devices. Then, we evaluate these impairments in objective to present the motivation to detect and monitor crosstalk in ONoC, which our system has the capability to detect, to localize, and to monitor the crosstalk noise in the whole network. This system offers high reliability, scalability and efficiency with time running time less than 20 ms
Radiation Pattern Control of Microstrip Antenna in Elevation and Azimuth Planes Using EBG and Pin Diode.
No full textAn important issue in wireless communication systems, which is related to the antenna gain degradation in case of changing the main direction of the antenna radiation pattern, this variation is not approval in many communications systems. In order to improve antenna radiation performances, Electromagnetic band gap (EBG) - antenna with radiation pattern control capability is presented. Mushroom-like EBG structure for suppressing surface waves has been combined, with the switching diode to produce the radiation pattern control with improving antenna characteristics of gain, directivity and efficiency. EBG of several cells are surrounded the patch antenna and placed symmetrically for the two opposite sides, generating different radiation patterns control ability in both the elevation (E) (-20° < φ < 20°) and azimuth (Z) planes (−18° < θ < 18°). At the ground plane of antenna the diodes have been switched ON and OFF states, the EBG sector properties in stop band (connecting vias) and pass band (disconnecting vias) are altered. Using CST Microwave Studio (CST MWS) the results show the flexibility in radiation pattern control for the Z and E planes using only four diodes. Antenna directivity of 10 dBi, gain 9.86 dB and efficiency 96.5% at the operating frequency of 6 GHz, more results for all direction has been stated in Table1. Significantly, unlike a conventional beam steering, this method does not suffering from gain degradation and the main lobe gain is approximately constant for all steering angles
Response of Polycrystalline Solar Cell Outputs to Visible Spectrum and Other Light Sources- A Case Study
No full textIn this case study, two polycrystalline solar modules were installed outdoors (irradiated by sunlight) and indoors (irradiated by artificial lights). The solar cells in both cases were installed using different color filters that allowed the passage of certain light frequencies. The amount of energy produced by each module were measured and compared to a reference module with no filter. The results indicated the variable response of polycrystalline solar cells to natural and artificial light sources, being more responsive in both cases to red band color as could be deduced from their % current outputs (72.5 % sunlight radiation; 84.38 % artificial light sources). Other colors, including yellow, green, orange and violet afforded acceptable outputs. The results indicated that electrical outputs of indoor solar cells decreased when colored filters were used, but red filter in general afforded the maximum outputs, for both the artificially radiated indoor and naturally radiated outdoor solar cells. The case study suggests the possible complementary advantage of using indoor mounted solar cells for the production of electricity during artificial illumination period of the day
Negative Total Float to Improve a Multi-Objective Integer Non-Linear Programming for Project Scheduling Compression
No full textThis paper presents Multi-Objective Integer Non-Linear Programming (MOINLP) involving Negative Total Float (NTF) for improving the basic model of Multi-Objective Programming (MOP) in case the optimization of the additional cost for Project Scheduling Compression (PSC). Using the basic MOP to solve the more complex problems is a challenging task. We suspect that Negative Total Float (NTF) having an indication to make the basic MOP to solve the more general case, both simple and complex of PSC. The purpose of this research is identifying the conflicting objectives in PSC problem using NTF and improving MOINLP by involving the NTF parameter to solve the PSC problem. The Solver Application, which is an add-in of MS Excel, is used to perform optimization process to the model developed. The results show that NTF has an important role to identify the conflicting objectives in PSC. We define NTF is an automatic maximum value of the activity duration reduction to achieve due date of PSC. Furthermore, the use of NTF as a constraint in MOINLP can solve the more general case for both simple and complex PSC problem. Base on the condition, we state that the basic MOP is still significant to solve the PSC complex problems using MOINLP as a sophisticated MOP technique
Establishment Network by using FSO link based on MD code for hybrid SCM-SAC-OCDMA Wireless system
No full textSince the wireless systems are working under nature environments and influenced by turbulence, weather in Iraq that leads to extended amount of fading signal, dissipation or attenuation. Basic “hybrid Subcarrier Multiplying Spectral Amplitude Coding (SCM-SAC) of Optical Code Division Multiple Access (OCDMA)" indoor or outdoor optical system depends on generally “Multi-Diagonal (MD)" security code by using optical space known as “Free Space Optic (FSO)" that was proposed in this work. It is found that the mention hybrid wireless systems can be used in operating mesh networks. The main proposed idea of hybrid optical technique was analyzed and simulated by normally taking into simulation account that the directly effecting by rain and haze attenuations. In addition, there are mention and description for atmospheric effects, FSO mesh network, modulation scheme, simulation, and the data security. From simulation results, the hybrid system using MD code produces reduced “bit-error rate (BER)" at heavy storm rain to distance or range of 500 m and at drizzle rain up to 2500 m range. And also investigates the performance of using the proposed system with radio over fiber (RoF) for UWB signals through indoor propagation in building applications of wireless channel