Cloud service performance evaluation: status,challenges, and opportunities – a survey from the system modeling perspective

With rapid advancement of Cloud computing and networking technologies, a wide spectrum of Cloud services have been developed by various providers and utilized by numerous organizations as indispensable ingredients of their information systems. Cloud service performance has a significant impact on performance of the future information infrastructure. Thorough evaluation on Cloud service performance is crucial and beneficial to both service providers and consumers; thus forming an active research area. Some key technologies for Cloud computing, such as virtualization and the Service-Oriented Architecture (SOA), bring in special challenges to service performance evaluation. A tremendous amount of effort has been put by the research community to address these challenges and exciting progress has been made. Among the work on Cloud performance analysis, evaluation approaches developed with a system modeling perspective play an important role. However, related works have been reported in different sections of the literature; thus lacking a big picture that shows the latest status of this area. The objectives of this article is to present a survey that reflects the state of the art of Cloud service performance evaluation from the system modeling perspective. This articles also examines open issues and challenges to the surveyed evaluation approaches and identifies possible opportunities for future research in this important field.     

Kumar’s, Zipf’s and other laws: how to structure a large-scale wireless network?

Networks with a very large number of nodes are known to suffer from scalability problems, influencing throughput, delay, and other quality-of-service parameters. Mainly applicable to wireless sensor networks, this paper extends prior work and aims to give some fundamental indications on a scalable and optimum (or near-optimum) structuring approach for large-scale wireless networks. In: European wireless 2007, Paris, April 2007 (conference CD-ROM), 2007) and aims to give some fundamental indications on a scalable and optimum (or near-optimum) structuring approach for large-scale wireless networks. Scalability and optimality will be defined with relation to various performance criteria, an example of which is the throughput per node in the network. Various laws known from different domains will be invoked to quantify the performance of a given topology; most notably, we will make use of the well-known Kumar’s law, as well as less-known Zipf’s and other scaling laws. Optimum network structures are derived and discussed for a plethora of different scenarios, facilitating knowledgeable design guidelines for these types of networks.     

Technology Convergence and Divergence in China’s Electronic Industries:Evidence from Patents

Companies may leverage their technology resource through focusing on special group of technical fields, or diversify their range of technology resource in order to control the future market by controlling technology development course. In either case, there would be a trend that leads to technology converging or diverging in sector level as well as in company level. International studies cover this area in recent years, with important indication that strategic movement for this technology conv…     

Towards successful VoLTE and VoWiFi deployment: network function virtualization solutions’ benefits and challenges

The Recent decades have witnessed intensive efforts from operators to implement methods enabling better control over network utilization, service usage, and service monetization. Nevertheless, they report significant growth in Diameter signaling traffic, especially policy management signaling traffic. More specifically, operators offering long term evolution (LTE) data-only services and planning for a massive introduction of voice over LTE (VoLTE) and voice over WiFi (VoWiFi) services need to tackle the enormous growth in Diameter signaling traffic. The biggest challenge for those operators is to find an appropriate solution, scalable enough to handle the unpredictable growth of Diameter signaling traffic; as the VoLTE and VoWiFi services will reshape the landscape of LTE policies. Throughout this paper, we propose a network function virtualization (NFV) based model, mature enough to tackle the challenges of those operators planning to launch VoLTE and VoWiFi, without impacting existing services and without jeopardizing current revenues. In our approach we first used standard VoLTE and VoWiFi message flow and referenced users’ behavior; then we considered NFV architecture characteristics. We finally referred to the latest experiments and test results related to NFV maturity cycle.     

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.     

Children’s perceptions of fairness in a data disclosure context: The effect of a reward on the relationship between privacy literacy and disclosure behavior

Children have increasingly become the target of commercial entities that seek their customer data. This study examines how young children deal with these requests and explores how enhancing their privacy literacy is related to real disclosure behavior. Additionally, the paper explores how this relationship is affected when companies provide a reward in exchange for the data and how it is mediated by how fair children think data practices are. An experiment with 496 children (9–13 years old) shows that privacy literacy negatively influences disclosure behavior. However, there is an interaction effect between privacy literacy and reward on perceived fairness, eventually affecting disclosure behavior. More specifically, children who are more literate find data practices to be fairer when a reward is provided, which in turn leads to greater data disclosure. Implications of the findings and directions for future research are discussed.     

Social media use and university students’ participation in a large-scale protest campaign: The case of Hong Kong’s Umbrella Movement

This study examines the impact of social media use on participation in large-scale protest campaigns that feature a range of participation opportunities. It develops a theoretical model which distinguishes between support generation and behavior activation effects, differentiates collective action, digital, and personalized action participation, and posits social media use as a mediator between social psychological predictors of protest behavior and actual participation. The empirical analysis focuses on Hong Kong’s Umbrella Movement in 2014. Analyzing a probability sample of university students (N = 795), the findings show that sharing political information and direct connections with political actors via social media have significant impact on both support for and participation in the Umbrella Movement. Social media use has effects on each dependent variable in the causal chain even after all the immediate causes are controlled. Social media use also mediates part of the impact of general political awareness, efficacy, and grievances on movement support and participation.     

Joint decoding of convolution codes and estimation of multipath communication channel’s parameters on a sliding interval

Optimal and quasi-optimal non-linear recurrent algorithms of joint decoding of convolution code and estimation of unknown multipath communication channel’s parameters on a sliding interval are synthesized on the basis of mathematics technique of mixed Markov processes in discrete time. Analysis of the obtained quasi-optimal algorithm is performed using statistical modeling on PC.     

Tartaglia-Pascal’s triangle: a historical perspective with applications

The aim of this paper is to provide a historical perspective of Tartaglia-Pascal’s triangle with its relations to physics, finance, and statistical signal processing. We start by introducing Tartaglia’s triangle and its numerous properties. We then consider its relationship with a number of topics: the Newton binomial, probability theory (in particular with the Gaussian probability density function, pdf), the Fibonacci sequence, the heat equation, the Schrödinger equation, the Black–Scholes equation of mathematical finance and stochastic filtering theory. Thus, the main contribution of this paper is to present a systematic review of the triangle properties, its connection to statistical theory, and its numerous applications. The paper has mostly a scientific-educational character and is addressed to a wide circle of readers. Sections 7 and 8 are more technical; thus, they may be of interest to more expert readers.     

Automatic detection of articulations disorders from children’s speech preliminary study

Automatic Detection of Articulations Disorders from children’s speech is the major interest for the diagnosis and monitoring of articulations disorders therapy. In this work, acoustic features LPC (Linear prediction cepstrum) have been used with the two most commonly used classifier GMM-UBM (Gaussian mixture model-universal background model) and SVM (Support Vector Machines). We have used the idea of stacking the means of the GMM-UBM model to form a mean super vector and introduce the resulting super vector to SVM system. The main contribution of this paper is the used of automatic speaker recognition to detect the articulation disorder from the children speech and the investigation of the performance gained using a hybrid strategy between GMM-UBM and SVM systems. Series of experiments will be conducted; demonstrations of results from different experiments will be presented, tested and evaluated. Indeed we have found that this method is effective and robust.     

Modeling of piezo actuator’s nonlinear and frequency dependent dynamics

To facilitate on-line identification and implementation of a piezoelectric actuator model for precision machining, this paper describes a hybrid hysteresis model integrating the classical Preisach model and a neural network. The incorporation of a neural network enables on-line model identification from operating data of a piezo (a great contrast to the tedious calibration process required by the classical Preisach model). The model is then extended to describe a piezo actuator’s frequency dependent behavior which is not possible for the classical model. Experimental results confirmed the accuracy of both models and the superiority of the extended one.     

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...     

Measurement of Young’s modulus of GaAs nanowires growing obliquely on a substrate

A convenient and fast method for measuring Young’s modulus of semiconductor nanowires obliquely standing on the growth substrate is presented. In this method, the nanowire is elastically bent under the force exerted by the probe of an atomic-force microscope, and the load-unload dependences for the bending of the probe cantilever are recorded. Next, these curves are used to find the bending stiffness of the tilted nanowires, after which, taking into account the nanowire dimensions, Young’s modulus is obtained. The implementation of this method is demonstrated for tilted GaAs nanowires growing on a GaAs (111) substrate. Young’s modulus is determined by applying finite-element analysis to the problem of the stationary elastic bending of a nanowire taking into account the actual nanowire shape and faceting. It proves that a fairly accurate estimate of Young’s modulus can be obtained even if the nanowire shape is approximated by a circular cylinder with a single cross-sectional area. The values of Young’s modulus obtained for GaAs nanowires of cubic lattice symmetry are 2 to 3 times smaller than its value for bulk GaAs. This difference is attributed to the presence of stacking faults in the central part of the nanowires.     

Proof of Chabaud and Vaudenay’s almost bent functions conjecture

This paper proves that the conjecture of Chabaud and Vandenay(Proc. Eurocrypt’94) is right.     

Mining and utilization of network protocol’s stealth attack behavior

The survivability,concealment and aggression of network protocol’s stealth attack behaviors were very strong,and they were not easy to be detected by the existing security measures.In order to compensate for the shortcomings of existing protocol analysis methods,starting from the instructions to implement the protocol program,the normal behavior instruction sequences of the protocol were captured by dynamic binary analysis.Then,the potential stealth attack behavior instruction sequences were mined by means of instruction clustering and feature distance computation.The mined stealth attack behavior instruction sequences were loaded into the general executing framework for inline assembly.Dynamic analysis was implemented on the self-developed virtual analysis platform HiddenDisc,and the security of stealth attack behaviors were evaluated.Excepting to mining analysis and targeted defensive the stealth attack behaviors,the stealth attack behaviors were also formally transformed by the self-designed stealth transformation method,by using the stealth attack behaviors after transformation,the virtual target machine were successfully attacked and were not detected.Experimental results show that,the mining of protocol stealth attack behaviors is accurate,the transformation and use of them to increase information offensive and defensive ability is also feasible.     

Collaborative handshaking approaches between internet of computing and internet of things towards a smart world: a review from 2009–2017

Internet of things (IoT) has been a noteworthy zone of research for empowering interconnection and joining the physical world through the Internet. At the beginning, it was used for single things but later advancements in different computing devices resulted in a new terminology called the internet of computing (IoC). In this paper, we review the latest progresses on IoT with IoC from a class review of published articles from 2009 to 2017. The review is classified alongside with (1) identification of users who are already in existence, (2) devices connected via various communication modes, (3) deterministic communication in IoT. The reviewed approaches are named as empirical, computing, innovative application and implementation approaches. The review shows that data stored in the cloud need to be mapped with geographic information system in order to fit with IoT and IoC. For IoT versus traditional communication approaches, it is found that reliable connection is one of the most emerging issues nowadays. It has been concluded that for the social consensus, IoC and IoT cooperating together are truly beneficial for upcoming years rather than just devices equipped with many sensor technologies. We hope to draw attention to this new topic with trends in the forthcoming era.