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Relational database management systems (RDBMS) have been imposed for more than three decades as a facto standard for data storage, management, and analysis. They have a good reputation by supporting ACID properties (Atomicity, Consistency, Isolation, and Durability) and by adopting the SQL language which has become a standardized language. However, despite their power, RDBMS have…

We examine design principles from more than 20 years of experience in the implementation and protection of mission critical flight systems used by the Mission Design and Navigation Section at NASA’s Jet Propulsion Laboratory. Spacecraft navigation has rigorous requirements for completeness and accuracy, often under critical and uncompromising time pressure. Fault tolerant and robust design…

STATCOM a shunt connected Flexible Alternative Current Systems (FACTS) device using for fast control of voltage and reactive power control in the power grid. To optimize Nouakchott power system at 2030 year, we anticipate both generation and demand grow. A set of nonlinear equations are solved through Newton Raphson method and programmed in PSS/E and…

The purpose of this work is to present new technology in acquiring energy from the compact fluorescent lamp (CFL) and store it in a super-capacitor to operate the emergency exit lights. Many studies show energy-efficient light bulbs may emit harmful radiation. This type of lamp emits high levels of radiation, causing migraine headaches, fatigue, and…

The telecommunications industry continues to move forward with plans for 5G service with rates including 6Gb/s followed by upgrade paths promising 20Gb/s. Despite advances in wireless technology associated with 5G roll-outs, there remains the problem of providing sufficient backhaul throughput and efficient handling of hand-off services within the relatively small projected cell boundaries that can…

Cloud computing is a technical “as-a-service” usage model utilizing virtualization. Virtual machines are the core of cloud computing that runs as independent machine grouped into different networks within the hypervisor. Practically done by deployment of clouds computing hosts enterprise servers in virtual machines on an array of high-end servers. Managing cloud resources has to do…

Cloud computing recently emerged as an interesting model that enables computing and other related internet activities to take place anywhere, anytime. Cloud service providers centralize all servers, networks, and applications to allow their users’ access at any time and from any location. Cloud computing uses already existing resources like server, CPU and storage memory but…

In Opportunistic Mobile social networks (OMSNs), the social characteristics and behavior of humans carrying mobile devices are exploited to improve information provision and data routing in the network. Social-based routing algorithms attempt to exploit users’ social features such as similarity, centrality and betweenness, singularly or combined, to select a suitable relay node among neighbors. However,…

The aim of this article is to analyze and evaluate the performance of Coordinated Multipoint (CoMP) transmission approach at a frequency of 28 GHz using three dimensional ray tracing simulations in an urban macrocellular environment. The new performance metric introduced in this article is the relative power usage. Other performance metrics examined in this article…

Consumers of electrical energy have looked more closely to the energy consumption in last years due to the successive increase of the electricity bill. Nowadays it is possible to notice that many consumers have been looking for ways to reduce their consumption or the value of their electricity bill. Such a cost reduction is obtained…

A method for coupling of local and global fields related to currents, voltages and magnetic fields in magnetodynamic problems is developed in the frame of the finite subproblem finite element method. The method allows to correct the errors arising from thin conducting regions, that replace volume thin regions by surfaces but neglect border effects in…

A systematic study of wide bandgap (WBG) based light emitting diodes (LEDs) and photodiodes (PDs) were conducted for the assessment of modular integration of optoelectronic devices into power modules. The temperature dependence of the photoluminescence (PL) efficiency of Indium gallium nitride/Gallium nitride (InGaN/GaN) multiple quantum wells (MQWs) material was studied from 10 to 800 K.…

This paper explores the problem of robust synchronization of complex dynamical network with stochastic coupling and time-varying delays through the application of nonfragile control. A well defined Lyapunov Krasovskii functional is established and by employing the widely acknowledged extended Jensen’s integral inequality and the Bernoulli’s distribution sequences, the stochastic nature of network coupling is modeled…

High Performance Computing (HPC) systems offer excellent metrics for speed and efficiency when using bare metal hardware, a high speed interconnects, and massively parallel applications. However, this leaves out a significant portion of scientific computational tasks, namely high throughput computing tasks that can be trivially parallelized and scientific workflows that require their own well-defined software…

The 5G is the fifth generation of mobile broadband, cellular technologies, and networks that promises a major change in mobility by evolving connected business realities. In such an emerging environment, reliable Service Level Agreements (SLA) and anticipation of breaches of Service Level Objectives (SLO) become compulsory. Thus, guaranteeing the required service quality, while also ensuring…

Network security challenges due to nearly limitless internet connectivity, platform limitations, ubiquitous nodal mobility and huge data transactions is burgeoning by the day and the need for transcend Internet of Things (IoT) based cloud security authentication protocols is on an exponential rise. Even though many secure classic layered security mechanisms are available for implementation, they…

Modern automobiles have been turning more and more into wireless sensor and communication networks. Accordingly, the number of radio systems is steadily increasing. Due to strict safety requirements, these radio systems need to be tested extensively for functionality and reliability, especially under poor radio channel conditions. Beside the large electrical size of cars at frequencies…

The task of optimal path planning for drilling tool with numerical control is considered. Such tools are used in the production of printed circuit boards. The algorithm modification of level-by-level route construction for the approximate solution of the traveling salesman problem is discussed. Bypass objects can be specified either as a table of distances or…

In this paper, behavioral approach has been adopted for the calculation of total power losses that has been further used to derive an analytical model for the conduction and switching losses in a boost Power Factor Correction (PFC) stage of an On-board Charger (OBC). Detailed investigation of power losses can help in finding out ways…

The presence of atmospheric hazards in confined space can contribute towards atmospheric hazards accidents that threaten the worker safety and industry progress. To avoid this, the environment needs to be observed. The air sample can be monitored using the integration of electronic nose (e-nose) and mobile robot. Current technology to monitor the atmospheric hazards is…

This paper investigates the methods of optimal design construction for step-stress accelerated life testing (ALT) when a Cox’s hazards model is adopted with either a linear or a quadratic baseline hazard function. We discuss multiple step-stress plans for time-censored ALT experiments. The maximum likelihood method is utilized for estimating the model parameters. The information matrices…

Just as electricity has an essential role in our lives, the internet network and especially web services have become of vital importance nowadays. Without security service layers, apparently small things like checking a child’s school schedule on web may turn the daily routine into a nightmare. Web services users are still required to use many…

Big data can be considered to be at the forefront of the present and future research activities. The volume of data needing to be processed is growing dramatically in both velocity and variety. In response, many big data technologies have emerged to tackle the challenges of collecting, processing and storing such large-scale datasets. High-performance computing…

We present a privacy-preserving approach for discovering nearby places of interest to Alice. In this approach, the proposed protocol allows Alice to learn whether there is any place that she is looking for near her. However, the location-based service (LBS) that tries to help Alice to find nearby places does not learn Alice’s location. Alice…

In today’s technology, 3D presentation is vital in conveying a realist and comprehensive understanding of a specific notion or demonstrating certain functionality for a specific device or tool, especially on the World Wide Web. Therefore, the importance of this field and how its continuous enhancement has become one of the dominant topics in web development…