Performance Assessment of Time Series Forecasting Models for Cloud Datacenter Networks’ Workload Prediction

The resource scaling has been influential in enabling the cloud service providers to provision the resources on-demand effectively. The prior estimation of workloads helps in addressing the scaling issues arises due to dynamic nature of the resource demands. In this paper, we evaluate six different forecasting approaches over real world workload data traces of web and cloud servers. The entire analysis is carried out three times as three different functions are used to measure the deviation in forecasts. The three forecast error measures are root mean squared error, mean absolute error, and mean absolute scaled error. We also carried out a statistical evaluation using Friedman test and Finner post-hoc analysis. The study concludes that the auto ARIMA process outperforms other models and achieves the best rank in the statistical analysis.

     

Performance Analysis of CSS Over α–η–μ and α–κ–μ Fading Channel Using Clustering-Based Technique

Wireless Personal Communications - Cooperative spectrum sensing (CSS) is an efficient method, which is used to detect the presence/absence of primary user (PU) signal in the received spectrum at...     

VHF–UHF Electric Field Prediction for Amazon City Using Dyadic Green’s Function

Wireless Personal Communications - This paper provides a method for predicting the electric field intensity using Dyadic Green’s Function in Two and Three-Layered Medium model for...     

Performance Evaluation of Wireless Communication Systems over Weibull/q-Lognormal Shadowed Fading Using Tsallis’ Entropy Framework

Wireless Personal Communications - In wireless communication channels, the signals arriving at the receiver may be of stochastic nature or be superpositioned due to non-uniform scattering and...     

Detection and Evaluation of Deterministic Jitter Causes in CP-PLL’s Due to Macro Level Faults and Pre-Detection Using Simple Methods

Charge-Pump Phase-locked loops are currently used in a variety of SoC signal generation applications. They ultimately determine performance of other SoC blocks, such as ADCs, DACs, RF and synchronisation functions. In many situations, only simple frequency lock tests are carried out on the CP-PLL portion of a circuit, with other complex direct jitter tests being carried out indirectly at a higher system level. Although these higher level system tests must generally be carried out at some point they can be time consuming. In addition, if the PLL is designed and operating correctly the PLL system will generally have far better performance than the system it is driving. This paper investigates typical jitter output responses of CP-PLLs when subjected to selected forward path leakage faults. The evaluation platform consists of a macro level mixed signal based PLL-Model. Degradation of the PLL output is evaluated from the phase noise spectrum, jitter spectrum and sideband spur degradation. Further evaluations and analysis are supplied relating block level effects to jitter and phase noise. Investigations are made as to the efficacy of detection of these errors with simple measurement techniques. The crux of the work is thus initially to develop techniques to aid evaluation of the likely jitter performance of a CP-PLL system without resorting to direct measurement techniques.Martin John Burbidge Is currently employed as a lecturer for the Microsystems research group at Lancaster University. He worked towards a HND in mechanical and electrical engineering from 1985 to 1987. From 1993 to 1996 he studied technology, mathematical modelling, and embedded micro controller design with the Open University. He received a first class honours degree in Electronic and Communications Engineering from Lancaster University in 1999. From March 2000, he was employed as a Research associate at Lancaster University and has been investigating and developing innovative test techniques and test paradigm shifts for Phase locked loops and frequency synthesis systems. During this period he has produced eleven conference and six journal publications. He also carries out his own consultancy activities in this area. His general interests include RF board level and ASIC design, design for test, and built in self-test relating to RF circuits.     

Innovative Citizen’s Services through Public Cloud in Pakistan: User’s Privacy Concerns and Impacts on Adoption

Mobile Networks and Applications - The world is going to be more and more digital with effective utilization of information and communication technologies in government services to provide services...     

A Study on Evaluation Model of IT Industry’s Innovation Capability Based Variable Weight Theory

Popularly, based on electronic information technology (micro-electronics technology mostly), IT industry include electronic information equipment’s exploitation and manufacture, providing information communication, system integration and software exploitation, etc. As the forerunner industry and support industry in national economy, IT industry has some characteristic, such as better penetrating capability and leading function, faster development speed and great increasing potential. It has …     

Radiation-Induced Fault Simulation of SOI/SOS CMOS LSI’s Using Universal Rad-SPICE MOSFET Model

The methodology of modeling and simulation of environmentally induced faults in radiation hardened SOI/SOS CMOS IC’s is presented. It is realized at three levels: CMOS devices – typical analog or digital circuit fragments – complete IC’s. For this purpose, a universal compact SOI/SOS MOSFET model for SPICE simulation software with account for TID, dose rate and single event effects is developed. The model parameters extraction procedure is described in great depth taking into consideration radiation effects and peculiarities of novel radiation-hardened (RH) SOI/SOS MOS structures. Examples of radiation-induced fault simulation in analog and digital SOI/SOS CMOS LSI’s are presented for different types of radiation influence. The simulation results show the difference with experimental data not larger than 10–20% for all types of radiation.     

Comments and Further Results on ‘Performance Evaluation of a New BPSK-OFDM Timing Estimation Algorithm’

This comment first points out some inaccurate formulae and irrelevant comparisons between Wen’s algorithm and Beek’s one. Then, the correct formulae are provided, the limitations of these two estimators are discussed and some investigations on the local maximum in timing estimation are also presented. Both the simulation and the analysis demonstrate that the timing precision of Wen’s algorithm highly depends on the length of cyclic prefix (CP) and the channel fading rate. On the other hand, Beek’s algorithm will work better under a large CP length and in fast fading channels.

Performance Analysis of Weather’s Impact on Outdoor IEEE 802.11b/g Links Using Network Management Parameters

Some previous works concluded that weather conditions impact on the performance of outdoor IEEE 802.11b/g links. They show high correlation coefficients between the number of control frame errors and the weather conditions. However, these previous studies do not consider grouping weather conditions into ranges and it would provide very valuable information in this issue. Knowing the weather conditions ranges where the weathers’ impact is really significant would be very useful for future outdoor networks. Thus, we have carried out a deep study on an experimental IEEE 802.11b/g setup in order to extract real conclusions. It is composed of two outdoor radio links of different lengths transmitting traffic continuously. Results show that in spite of covering a lower distance, the short distance link is more susceptible to the weather conditions. It is due to the modulation scheme used in that case. Moreover, they show different correlation coefficients depending on the groupings of weather conditions.     

A Novel Cross-Layer Cross-Domain Routing Model and It’s Optimization for Cluster-Based Dense WSN

Wireless Personal Communications - Wireless Sensor Networks (WSNs) plays its adorable performance in the current day communication as it could sense different environmental and physical parameters...     

Contiki IEEE 802.15.4 MAC Layer Protocols: Implementation and Evaluation of Node’s Throughput and Power Consumption

Wireless Personal Communications - Internet of Multimedia Things (IoMT), a special subset of Internet of Things (IoT), is a novel paradigm which is progressively increasing and gaining in...     

Generation of mm- and Sub mm-wave Bessel Beams Using DOE’s Designed by BOR-FDTD Method and MGA

A new way for generating Bessel beams at mm and sub mm-wavelengths is presented in this paper, in which diffractive optical elements (DOE’s) are designed for converting incident Gaussian beams into Bessel beams. In order to reduce the computational burden and therefore improve the design efficiency, two measures are adopted in our design. One is a body-of-revolution finite-difference time-domain (BOR-FDTD) method that uses a two-dimensional (2-D) solution space instead of a full 3-D space and thereby saves tremendous computational resources, and that is utilized to calculate the fields diffracted by the DOE’s. The other is a microgenetic algorithm (MGA) that has been proved to be more effective than the conventional GA, and that is employed for accelerative optimization. The utility of the present design tool, which combines a MGA with a BOR-FDTD method, is demonstrated by three examples. Numerical simulation results indicate that the designed DOE’s can not only flexibly generate zero- or higher- order Bessel beams when compared with axicons, but also have higher diffraction efficiencies when compared with amplitude holograms. An erratum to this article can be found at     

Mobile Phone Antenna Performance and Power Absorption in Terms of Handset Size and Distance from User’s Head

In this work numerical simulation and measurements of three-dimensional radiation patterns of a mobile handset model in the presence of a human head phantom were performed at 1800 MHz. Based on theoretical and experimental results, the influence of the human head on the radiation efficiency of the handset has been investigated as a function of the handset size and the distance between the head and the handset during its operation. Furthermore, the relative amount of the electromagnetic power absorbed in the head has been obtained. It was found that significant reduction of the absorbed power (about 50%) with proportional increment of the handset radiation efficiency could be achieved by moving the phone for 1 cm only away from the head. Agreement between theoretical and experimental results was found to be very good.Theodore Zervos was born in Athens, Greece, on October 5, 1978. He received the diploma in Electrical & Computer Engineering from the University of Patras, Patras, Greece, in 2001. He is currently a Postgraduate Student at the Laboratory of Electromagnetics, Department of Electrical & Computer Engineering, University of Patras. He is also a doctoral scholar at the Mobile Communications Laboratory of the Institute of Informatics and Telecommunications of NCSR Demokritos, Athens. His research interests include electromagnetic modelling, EM radiation measurements and interaction between the human body and mobile handsets antenna. Dipl. T. Zervos is a Member of the Technical Chamber of Greece. In June 2002, his thesis received the 2nd Award of Excellence in Telecommunications from Ericsson.Antonis Alexandridis (1962) is senior researcher in the Institute of informatics and Telecommunications (IIT) of Greek National Research Centre (NCSR) Demokritos. He received the diploma in Electrical Engineering from Technical University ofPatras, Greece (1985), and the Ph.D. degree from the same University (1992). From 1993 he is working in the Mobile Communications Lab of NCSR. Since 1999 he is responsible for the operation of the RF Anechoic Chamber of the IIT. His current interests include mobile communications, propagation models, spread spectrum systems and CDMA techniques, EMC measurements, human exposure to EM fields, interaction between human body and mobile terminals antennas and smart antennas.Vladimir V. Petrovic was born in 1965 in Belgrade, Serbia. He received the B.Sc., M.Sc., and D.Sc., degrees from the University of Belgrade, Serbia and Montenegro in 1989, 1993, and 1996, respectively. He joined the Faculty of Electrical Engineering, University of Belgrade in 1990, where at present he is an Assistant Professor in Electromagnetics and Fundamentals of Electrical Engineering. He is a co-author of a chapter in a monograph, a software package AWAS 2.0 (Artech House – Boston, London, 2002) and several journal and conference articles. His research interests are in numerical electromagnetics, especially in radiation and propagation problems in layered media.Kostas Dangakis was born in Kavala, Greece, in 1950. He received his Diploma in Electrical Engineering from NTUA (Athens, 1973) and his Ph.D. on Digital Modulation/Data Transmission from Techn. Univ. of Patras, Dept. of Electrical Engineering (1984). Since 1977, he has worked at the Inst. of Inform. & Telecom. (IIT) of NCSR Demokritos, in projects related to voice/data/video signal encryption, synchronisation techniques in TDM systems, digital modulation techniques/data transmission, Spread Spectrum/CDMA techniques, mobile communications, conformance testing (DECT, ERMES), radio propagation, channel characterization and antennas. He is research director at IIT and has been project leader of several R & D projects.Branko M. Kolundzija Antonije R. Djordjevic was born in Belgrade, Yugoslavia, on April 28, 1952. He received the B.Sc., M.Sc., and D.Sc. degrees from the Faculty of Electrical Engineering, University of Belgrade, in 1975, 1977, and 1979, respectively. In 1975, he joined the School of Electrical Engineering, University of Belgrade, as a Teaching Assistant. He was promoted to an Assistant Professor, Associate Professor, and Professor, in 1982, 1988, and 1992, respectively. In 1983, he was a Visiting Associate Professor at Rochester Institute of Technology, Rochester, NY. Since 1992, he has also been an Adjunct Scholar with Syracuse University, Syracuse, NY. In 1997, he was elected a Corresponding Member of the Serbian Academy of Sciences and Arts. His main area of interest is numerical electromagnetics, in particular applied to fast digital signal interconnects, wire and surface antennas, microwave passive circuits, and electromagnetic-compatibility problems.C. Soras received both his diploma and Ph.D. in electrical engineering from the University of Patras, Patras, Greece, in 1981 and 1989 respectively. He was a Lecturer in the Laboratory of Electromagnetics of the Electrical and Computer Engineering department of the University of Patras in Greece from 1991 to 2001, where currently serves as an Assistant Professor. He is teaching the basic electromagnetic courses and at the senior undergraduate / graduate level computational electromagnetics. His current research interests focus on computational electromagnetics, multiple element antennas for diversity and MIMO terminal devices and indoor radio wave propagation. Prof. Soras is a member of IEEE, Applied Computational Electromagnetics Society and the Technical Chamber of Greece.     

Detection of Breast Masses in Mammogram Images Using Growing Neural Gas Algorithm and Ripley’s K Function

Breast cancer is a serious public health problem in several countries. Computer-aided detection/diagnosis systems (CAD/CADx) have been used with relative success in aid of health care professionals. The goal of such systems is not to replace the professionals, but to join forces in order to detect the different types of cancer at an early stage. The main contribution of this work is the presentation of a methodology for detecting masses in digitized mammograms using the growing neural gas algorithm for image segmentation and Ripley’s K function to describe the texture of segmented structures. The classification of these structures is accomplished through support vector machines which separate them in two groups, using shape and texture measures: masses and non-masses. The methodology obtained 89.30% of accuracy and a rate of 0.93 false positives per image.     

Chirped and Chirp-Free Optical Solitons in Fiber Bragg Gratings with Kudryashov’s Model in Presence of Dispersive Reflectivity

Journal of Communications Technology and Electronics - In this paper, the extended Kudryashov’s method has been successfully implemented to obtain optical solitons and other solutions to...     

Characterization of Electrical Properties of AlGaN/GaN Interface Using Coupled Schr?dinger and Poisson’s Equations

The electrical characterization of AlGaN/GaN interface is reported. The dependence of two-dimensional electron gas (2-DEG) density at the interface on the Al mole fraction and thickness of AlGaN layer as well as on the thickness of GaN cap layer is presented. This information can be used to design and fabricate AlGaN/GaN based MODFET (modulation doped field effect transistor) for optimum DC and RF characteristics.