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Communication, an essential aspect of human existence, has undergone a transformation with the advent of media, progressing from traditional to digital platforms in what is commonly referred to as the "Second Media Age." Within this context, computer-mediated communication (CMC) has introduced emojis as substitutes for nonverbal cues. However, the misuse of emojis may result in legal repercussions, as evidenced by documented cases. This study seeks to examine the understanding of specific emojis among the students at Alvan Ikoku Federal University of Education, Owerri, with the objective of contributing to the comprehension of this phenomenon and raising awareness of the potential legal implications. Utilizing the theoretical framework of Symbolic Interactionism, this study explores the diverse interpretations of emojis, while considering cultural nuances and discrepancies across platforms. The findings underscore the importance of being cognizant of the context in which emojis are employed in order to prevent misunderstandings. As emojis continue to shape the landscape of digital communication, it is crucial to consider their legal implications and strive for effective and responsible communication in the digital age. [ABSTRACT FROM AUTHOR]

The article presents a review of four recent books by authors Meredith Broussard, Tonia Sutherland, Wendy Hui Kyong Chun, and Catherine Knight Steele relating to the topic of racial and gender inequalities inherent in emerging digital technologies. The reviewer relates her approach to developing a lesson plan around these books.

Previous research suggests that user characteristics such as web experience and demographics may affect online trust. Drawing on social cognitive theory, we explore the moderating effect of user characteristics on online trust. Based on a survey of German Internet users, we differentiate three groups by age, web experience, and education. We term these groups digital natives, digital immigrants, and naturalized digitals. A multiple-group analysis reveals significant differences in trust formation, particularly in the cues considered in the evaluation of online services. Whereas a large user base inspires confidence in digital natives, naturalized digitals are more geared toward familiar brands and recommendations. Digital immigrants most critically weigh the risks of a transaction against its benefits. We argue that specific user characteristics are associated with distinct cognitive schemata, implying distinct interests and evaluations in online transactions. Online services should differentiate their signaling efforts according to the targeted customer group. [ABSTRACT FROM AUTHOR]

The transition to adulthood, often accompanied by an emptying of the family nest, has implications for family relationships, identities and consumption practices. Despite this, the voices and experiences of emerging adults are largely missing from literature on family consumption. Emerging adult families typically combine digital natives and digital immigrants, but little is known about how their interactions around digital communications technology relate to emerging adult preoccupations with affiliation and autonomy. This interpretive study explores how emerging adults’ smartphones are bound up with a complex network of family communication and consumption practices, often across household, geographic and generational boundaries. Affiliation and autonomy emerged as intertwined rather than competing dimensions of participants’ smartphone use, contributing to the distribution and development of family as the nest empties. [ABSTRACT FROM PUBLISHER]

Research on digital communication is best served by concentrating not on current technological tools , but rather on the novel processes of social and communicative change to which such technologies are often closely linked. Thus, scholarship should consider contemporary technologies mainly as manifestations of underlying phenomena rather than as particular objects of study and should cultivate a focus on the capabilities that span technologies. Theories in this domain, in turn, must concentrate on what is exceptional about technologies in terms of the psychological, social, and behavioral mechanisms that help to comprehend them in the long term. Seen this way, the key to understanding technological mediation is remarkably consistent even in the face of radical technological change. [ABSTRACT FROM AUTHOR]

Metamaterials made up of resonant elements containing lossy metallic conductors will invariably give rise to Johnson noise. A model based on nearest neighbor interaction of magnetically coupled elements is shown to predict the propagation of noise waves and the excitation of resonances in regular arrays. The power spectral density (PSD) of the noise is calculated for rectangular arrays of different dimension. It is shown that the effect of coupling is to alter the PSD, leaving the noise bandwidth unaltered. The implications for passive and active devices are examined using the simple model of a lossy one-dimensional interconnect with distributed parametric amplification, and it is shown that the improvements to the noise factor offered by amplification are limited. [ABSTRACT FROM AUTHOR]

Copyright of Journal for Business, Economics & Ethics / Zeitschrift für Wirtschafts und Unternehmensethik is the property of Nomos Verlagsgesellschaft mbH & Co. KG and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Orthogonal frequency-division multiplexing (OFDM) modulation, which is commonly used in modern digital communication systems due to its flexibility and high spectral efficiency, is sensitive to transmitter nonlinearities introduced by the power amplifiers (PAs). As a key technology in wireless transmitting systems, digital predistortion (DPD) is widely applied to compensate for the transmitter nonlinearities and ensure high power-added efficiency in base stations and mobile devices for cellular systems. In a DPD architecture, the transmitter input and output signals are sampled, aligned, and processed to extract the DPD parameters that would be used to predistort the source signal before transmission to counteract the transmitter nonlinearities. However, the alignment accuracy in DPD is limited by nonideal electronic components and the associated circuitry, which introduces unknown loop delay mismatch and, thus, degrades the overall linearization performance. In this paper, we analyze the effect of a loop delay mismatch on PA model identification and, hence, on DPD linearization performance of the wideband OFDM signals. The expression and upper limit for the normalized mean square error (NMSE) are derived in terms of the loop delay mismatch, transmission signal bandwidth, and signal-to-noise ratio (SNR) of the feedback channel. The expression for the adjacent channel leakage ratio (ACLR) performance is also derived to predict the DPD linearization performance with the presence of the loop delay mismatch. The theoretical analysis reveals that the performance degradation increases with the bandwidth of the OFDM signal and the modulus of the loop delay mismatch. Experiments are performed on the Long-Term Evolution (LTE) Advanced signals with bandwidth ranging from 20 to 100 MHz to evaluate the degradation effect of the loop delay mismatch on the NMSE and ACLR performances. [ABSTRACT FROM PUBLISHER]

In DVB-T/T2 broadcasting single frequency network (SFN) multipath interference (MPI) at the receiver antenna is a critical issue. The capability to elaborate those signals depends on both synchronization strategy used and coded orthogonal frequency-division multiplexing (COFDM) modulation properties. An efficient COFDM system requires the guard interval as short as possible and such as to protect the system from the MPI. To cope with this problem a static delay adjustment obtained by fitting the launching time of each broadcast station is introduced so that the time difference of the incoming signals within the reception area falls into the COFDM guard interval. This work investigates the use of advanced simulated annealing to optimize transmission parameters such as the static delay, gain and orientation of sector antennas of DVB-T/T2 transmitters in SFNs. In particular, we identify the static delay adjustment map to maximize the coverage area according to quality of service requirements. The proposed approach has been validated for DVB-T/T2 network planning in the Basque Country (Spain) and Sardinia island (Italy). Different density of transmitters, generalized geography of territory are considered for the best setting of the parameters involved. Reliability studies are included to demonstrate the efficacy of the method. [ABSTRACT FROM AUTHOR]

Advent of TV white space digitization has released frequencies from 470 MHz to 790 MHz to be utilized opportunistically. The secondary user can utilize these so called TV spaces in the absence of primary users. The most important challenge for this coexistence is mutual interference. While the strong TV stations can completely saturate the receiver of the cognitive radio (CR), the cognitive radio spurious tones can disturb other primary users and white space devices. The aim of this paper is to address the challenges for enabling cognitive radio applications in WLAN and LTE. In this process, architectural considerations for the design of cognitive radio front ends are discussed. With high-IF converters, faster and flexible implementation of CR enabled WLAN and LTE are shown. The effectiveness of the architecture is shown by evaluating the CR front ends for compliance of standards namely 802.11b/g (WLAN) and 3GPP TS 36.101 (LTE). [ABSTRACT FROM AUTHOR]

Interactive online video applications, such as video telephony, are known for their vulnerability to network condition. With the increasing usage of hand-held wireless mobile devices, which are capable of capturing and processing good quality videos, combined with the flexibility in an end-user movements have added new challenging factors for application providers and network operators. These factors affect the perceived video quality of mobile video telephony applications, unlike conventional video telephony over desktop computers. We investigate this impact on video quality of mobile video telephony in varying network conditions and end-users movement scenarios. Based on 312 live traces, we quantitatively derive the correlation between the perceived video quality and the network Quality of Service (QoS) and user mobility. With the results, we develop a Quality of Experience (QoE) prediction model for mobile video telephony using Support Vector Regression techniques. The prediction models display ≈ 0.8 pearson correlation with experimental data. Our methodology and findings can be used to guide the video telephony application providers and network operators to work towards satisfying end-user experience. [ABSTRACT FROM AUTHOR]

This paper proposes a robust sampling frequency offset (SFO) estimation scheme in an orthogonal frequency division multiplexing based digital radio mondiale system with non-symmetrically distributed pilots. In particular, a post fast Fourier transform SFO estimation method is suggested to provide an unbiased estimate of SFO in the presence of frequency selectivity of the channel as well as non-symmetrically distribution of pilot symbols. In order to verify the performance of the proposed frequency-offset estimation scheme, a closed-form expression for the mean square error (MSE) is derived. We show via simulations that the proposed estimation scheme achieves a remarkable robustness against frequency selectivity fading and the theoretical MSE analysis is proven accurate. [ABSTRACT FROM AUTHOR]

Low-Density Parity-Check (LDPC) codes are an efficient way to correct transmission errors in digital communication systems. Although initially targeting strictly to ASICs due to computation complexity, LDPC decoders have been recently ported to multicore and many-core systems. Most works focused on taking advantage of GPU devices. In this paper, we propose an alternative solution based on a layered OMS/NMS LDPC decoding algorithm that can be efficiently implemented on a multi-core device using Single Instruction Multiple Data (SIMD) and Single Program Multiple Data (SPMD) programming models. Several experimentations were performed on a x86 processor target. Throughputs up to 170 Mbps were achieved on a single core of an INTEL Core i7 processor when executing 20 layered-based decoding iterations. Throughputs reaches up to 560 Mbps on four INTEL Core-i7 cores. Experimentation results show that the proposed implementations achieved similar BER correction performance than previous works. Moreover, much higher throughputs have been achieved by comparison with all previous GPU and CPU works. They range from x1.4 to x8 by comparison with recent GPU works. [ABSTRACT FROM PUBLISHER]

The article describes an iterative algorithm for sparcity enforcing near-field acoustical holography over a wide frequency range based on the application of an optimized pseudo-random array geometry. Topics discussed include the method called wideband holography (WBH) as an example of remote sensing. Also mentioned are WBH being tested by real measurements on a pair of two-way loudspeakers and a car engine as well as typical application areas, such as engines and gearboxes.

The error vector magnitude (EVM), used generally to quantify digital communication performances, will be used in this paper in order to test RF device performances. This RF test particularly developed for industries will respond to time and cost-reduction requirements. The method is based on the simplest digital modulation, quadrature phase-shift keying modulation on an RF carrier frequency. Primary results based on this method have been obtained using Butterworth and Chebyshev RF filters. In this work we improve the sensitivity of the EVM parameter to filter characteristics as the center frequency, the bandwidth, the insertions losses, and the ripples in the passband. Simulations with ADS Ptolemy and measurements are done for both filter types with the aim of defining their EVM signatures in the passband. [ABSTRACT FROM PUBLISHER]

This paper compares the retrieval of significant wave height (SWH) from reflected signals of opportunity in the L-band, S-band, and Ku-band. The fundamental observation is the time series of the interferometric complex field (ICF) of the reflected signal. A known relationship between the coherence time of the ICF time series (width of the ICF autocorrelation function) and SWH of the ocean is used for this retrieval. This relationship is applied to data recorded at three frequencies in the S-band, L-band, and Ku-band. The accuracy obtained for S-band and L-band were on the order of 0.4 m, but this model saturated around the SWH value of 3 m. A secondary algorithm used spectral bandwidth to estimate SWH. This model showed linear dependence, with the error also around 0.4 m. The ICF coherence time for Ku-band signals showed little sensitivity to SWH. Furthermore, the effect of fully developed sea, wind, and wave directions on SWH retrieval is analyzed. [ABSTRACT FROM PUBLISHER]

In this paper, an improved version of the noncircular complex FastICA (nc-FastICA) algorithm is proposed for the separation of digital communication signals. Compared with the original nc-FastICA algorithm, the proposed algorithm is asymptotically efficient for digital communication signals, i.e., its estimation error can be made much smaller by adaptively choosing the approximate optimal nonlinear function. Thus, the proposed algorithm can have a significantly improved performance for the separation of digital communication signals. Simulations confirm the efficiency of the proposed algorithm. [ABSTRACT FROM AUTHOR]

A trend, where voluntary groups teach children and youth basic computer coding skills, has spread throughout the world. After-school clubs invite children to create games in visual programming environments. The activities emphasize play, while teaching principles of computer science. We explore this phenomenon based on observations and interviews at a code club in Norway, asking whether coding represents an important skill for children and how it is distributed to include all children. We find that coding through play activity is perceived as teaching more than simply the technical skills of programming. Although the fun aspect draws in children and volunteers, parents and instructors describe the code club as being about learning to understand and control the computer, and digital competence required for achieving success in society. The Code Club is described partly as being a ‘necessity for becoming a good/efficient/empowered citizen in our digital society’, and partly as ‘children are playing with computers anyway’. These arguments have different consequences for the gender imbalance at the Code Club. Our findings suggest that the code clubs need an explicit recruitment strategy targeting girls in order to become an arena where girls can develop interest and competence in digital technologies. [ABSTRACT FROM PUBLISHER]

Time-domain equalizer (Proakis in Digital communications, McGraw-Hill, New York, ) is one of most promising approaches to combat the interference caused by the mulitpath effect, and important for many applications in the wireless communication. We therefore investigate a simple universal time-domain minimum mean square error-decision feedback equalizer with a simple adaptive channel estimator to approach the near-optimal performance for mobile users. Furthermore, the method can be readily extended to the receivers incorporating with time-domain equalizers in other wireless communication scenarios such as OFDM systems over doubly selective channels. Using the Givens rotation based Cholesky factorization, the optimum feedforward and feedback coefficients can be easily derived with very low complexity. The simulation results demonstrate that the proposed method can approach the near-optimum performance using LMS channel estimation, and is suitable for the mobile terminals. [ABSTRACT FROM AUTHOR]

Analytical performance evaluation of a digital communication system remains a serious problem especially when a sophisticated digital signal processing is considered. Moreover, it is difficult to obtain the expected performance of such system using the Monte Carlo simulation method. In this paper, we propose a new semi-analytical approach for predicting error probability in a digital communication system. This approach is based on Fourier transform inversion formula to estimate the probability density function (pdf) of the observed soft sample at the receiver. Furthermore, we applied a bootstrap method for selecting the optimal smoothing parameter to make the proposed semi-analytical method more accurate. Simulation results show that the obtained semi-analytical error probability is close to the one measured using Monte Carlo simulation and provides a significant gain in terms of computing time. Besides, the use of the bootstrap method decreases the squared error between the true pdf and the estimated one. [ABSTRACT FROM AUTHOR]

This article investigates the strategies web-writers develop when their audiences respond to them via textual participation. Focusing on three web-writers who want to “continue the conversation,” this article identifies five major strategies to accomplish this aim: (a) editing after production, (b) quotation, (c) question posing, (d) naming secondary writers, and (e) textual listening. Using the lens of writer-audience tension, I find that due to these web-writers’ perceptions of audience, one that is partially externalized via the website’s template, the term audience itself may not be a discrete concept, but a fluid, evolving, and recursive one, in other words, ongoing. These perceptions of audience reflect the unending nature of online texts and are exemplified by these five strategies. [ABSTRACT FROM AUTHOR]

In this paper there are presented both architecture and more important functions and range of services of GSM-R (Global System for Mobile Communication - Rail). GSM-R is used for management and signaling support in railway transport. Particular attention was drawn to selected issues of IT and mobile security of services provided by GSM-R. [ABSTRACT FROM AUTHOR]

Sound is an important part of our experience of buildings. However, architects design largely using visually based techniques and largely for visual phenomena. Aiming to address this problem, the research presented in this paper proposes four digital design workflows that integrate acoustic computer simulation into architectural design. These techniques enable architects to design for both visual and acoustic criteria. The goal is to develop rapid and accessible workflows for architects that allow acoustic performance to be tuned as geometry and materials are modified at the scale of the room, and also at the scale of the surface. The discovery and testing of these techniques takes place within the design of the FabPod, a semi-enclosed meeting room situated within an open-plan working environment. The project builds on previous research investigating the design principles, the acoustic performance, and the fabrication methods of hyperboloid surface geometry. Four design workflows were developed: two of these investigate the acoustic performance of the room and use existing acoustic simulation software, and the other two workflows investigate the acoustic performance of the surface and use custom-written scripts to calculate and visualize sound scattering. This paper presents the background to the study, outlines the digital workflows, describes how they integrate acoustic simulation, and shows some of the data produced by these simulations. [ABSTRACT FROM AUTHOR]

The use of digital communication technologies, and of mobile phones in particular, has seen an exponential rise in low- and middle-income countries over the last decade. These data, emitted as a byproduct of technologies such as mobile phone location information and calling metadata, have the potential to fill some of the problematic gaps in data resources available to country policymakers and international development organisations. Using three examples of current big data initiatives in the international development field, we examine the implications of these new types of data for development policy and planning: their advantages and drawbacks, emerging practices relating to their use, and how they potentially influence ideas and policies of development. We also assess the politics of these new types of digital data, which are often collected and processed by corporations or by researchers in industrialised countries. Our analysis indicates that these new data sources already represent an important complement to country-level statistics, but that there are currently important challenges which will need to addressed if the promises of big data in development are to be fulfilled. [ABSTRACT FROM AUTHOR]

The article describes research on dishes segmentation for the purposes of customer service process automation in a self-service canteen. The project assumptions and a prototype test stand are presented. The developed empty workspace detection and tray position determination algorithms are discussed. Finally, the chosen dishes segmentation algorithm is described and justified. [ABSTRACT FROM AUTHOR]

Recent protests have fuelled deliberations about the extent to which social media ignites popular uprisings. In this article, we use time-series data of Twitter, Facebook, and onsite protests to assess the Granger causality between social media streams and onsite developments at the Indignados, Occupy, and Brazilian Vinegar protests. After applying Gaussianization to the data, we found contentious communication on Twitter and Facebook forecasted onsite protest during the Indignados and Occupy protests, with bidirectional Granger causality between online and onsite protest in the Occupy series. Conversely, the Vinegar demonstrations presented Granger causality between Facebook and Twitter communication, and separately between protestors and injuries/arrests onsite. We conclude that the effective forecasting of protest activity likely varies across different instances of political unrest. [ABSTRACT FROM AUTHOR]

Introduction. In the current era of digital communication, users share information they consider important, using wikis, blogs and social networking Websites. The digital content includes valuable as well as biased, false and demagogic information. The objectives of this review paper are, i) To understand the perceptions of users regarding Web credibility judgment and the problems faced by them, ii) To review and list the factors used in various Web credibility judgment techniques, iii) To suggest a hybrid model that takes advantage of different credibility judgment techniques. Method. This paper adopted a systematic review methodology based on the guidelines of Kitchenham. Analysis. Over 100 papers were reviewed to compile the list of factors covered in the approaches. These analyses were summarized in the form of tables featuring the methods, types and categories of approaches as well as the factors covered. Results. Our findings show that by adopting more than one approach when assessing the credibility of a Web, measuring credibility assessment becomes easier. Therefore, a hybrid approach is presented for the conduct of credibility assessment using the different approaches available to measure accuracy, authority, aesthetics, professionalism, popularity, currency, impartiality and quality. Conclusions. This paper hopes to contribute to the body of knowledge related to the identification of the factors (and categories they belong to) affecting Web credibility judgment and highlights the importance of a hybrid model for making accurate and effective Web credibility judgments. [ABSTRACT FROM AUTHOR]

The current paper is based on the hypothesis that communication through the new digital technologies modifies the moral response of users, and therefore reduces social capital. This approach has been contrasted by designing and conducting an experiment (N = 196) using our own adaptation of the Spanish version of the Defining Issues Test on subjects who have been socialized by Internet and who constitute the representative samples of this study. This test on paper was adapted to our research following an expert validation procedure and then transferred onto two types of digital audiovisual formats. Finally, The use of digital communication technologies and students' fluid intelligence response were evaluated in order to establish whether their response was significant and if it modified moral response. The results confirm the hypothesis and show that the quality of moral response decreases when digital technologies are used instead of pencil and paper. This difference is greater when virtual images of people designed by animation are used rather than visual images of real people. In addition, the results show that fluid intelligence mitigates these modifications. [ABSTRACT FROM AUTHOR]

Over the past decades, research on opinion leaders has been based on an implicit assumption that the structure of social networks is stable and that only attitudes and behavior are subject to change in a diffusion process. The finding that social groups often display similar attitudes or behavior was therefore regarded as evidence of opinion leaders' influence. However, network autocorrelation also can emerge due to social selection processes in which likeminded people establish new ties and cut dissonant ties. In fact, without controlling for social selection processes, one is likely to overestimate the power of influence processes. Stochastic actor-oriented modeling of dynamic social networks allows disentangling and quantifying these two processes. This reanalysis of a four-wave panel survey of adolescents' conversation networks and their TV use is the first to do this on the level of specific TV programs. The results demonstrate that influence of opinion leaders may become insignificant if parameters for social selection and general patterns of program preferences are included in the analysis. Overall, this study challenges an overly simplistic view of opinion leadership and illustrates the power of longitudinal social network analysis for disentangling social influence and social selection processes. [ABSTRACT FROM AUTHOR]

This article examines developments at public-service and state-administered media organizations based on a global sample of country case studies and selected secondary data. Most public-service and state media organizations have experienced a decline in revenue and audience and a tendency to weaken the program remit, but the overall direction of change is not one of uniform, marked, or irreversible decline. Although successful models of public service for the digital age have emerged, recent evidence suggests that neither the weakening of state broadcasters nor their reform into independent public-service media are inevitable results of digitization. [ABSTRACT FROM AUTHOR]

Digital newspaper archives are the most widely used resource for digital humanities research. The basic functionality of these archives -- the ability to perform keyword searches across multiple titles -- is unlikely to change. This means that researchers can safely develop a digital methodology without having to fear that new technology will make their efforts obsolete. On the basis of this observation, this article discusses three methodological problems of the digital newspaper archive. First, it provides unequal access to both different scholars and historical periods. Second, it tends to ignore the historical form of media landscapes. Third, the digital mediation of newspapers and periodicals results in a problematic loss of context. This article proposes that the solution to these problems lies in the assertion of agency over the digital newspaper archive and in the debates surrounding them by researchers. They should see digital newspaper archives as any other paper archive: with its own possibilities and limitations, which can be adjusted by the researcher. [ABSTRACT FROM AUTHOR]

Copyright of Socioeconomica is the property of Scientific Society Akroasis and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In home networks, multimedia content sharing has become commonplace. An open industry standard for seamless multimedia content access, called Digital Living Network Alliance (DLNA), provides guidelines designed to facilitate contents discovery, management, sharing, and distribution in consumer environment. Consumer experience with DLNA certified devices, however, has been rather poor and usability not up to speed. Despite the availability of DLNA interoperability guidelines, manufacturer customizations often lead to limited compatibility. Such compatibility issues lead to limited interoperability and are difficult to identify. In order to solve these problems, the design and implementation of an interoperability analyzer for DLNA devices is presented in this paper. The proposed analyzer monitors the home network, performs analysis of the underlying protocols used by DLNA, and identifies compatibility and interoperability issues between the devices. Especially, its Filter Component extracts only data relevant to DLNA in order to reduce the amount of analysis data and provide the user with only useful information. In addition, its Parser Component retrieves data from the database, parses the data, and performs conformance analysis. [ABSTRACT FROM AUTHOR]

A compact ultra wide band (UWB) antenna with dual band notch characteristics is proposed. The antenna consists of a coplanar waveguide (CPW) fed bevelled rectangular patch and a modified rectangular ground plane. A Z-shaped meander line parasitic element and a pair of symmetrical L-shaped quarter-wavelength stubs are employed to realise band-notched functions at WiMAX and WLAN bands respectively. By optimizing the dimensions and positions of these notch structures, the desired notch-bands of WLAN and WiMAX are achieved. Unlike other dual band-notched antennas reported in literature this antenna has a merit of regulating the centre frequency as well as the bandwidth of both the notched bands easily and independently. The measured -10 dB S11 covers the bandwidth from 2.5 to 11.5 GHz, with two notched bands from 3.3 to 3.6 GHz and 5.2 to 5.75 GHz. The proposed antenna exhibits nearly omni-directional radiation patterns with moderate gain and small group delay variations less than 0.5 ns over the entire operating bandwidth except at the notched bands. Moreover, by using antenna transfer function, the time domain characteristic of the antenna is also studied to confirm its suitability for UWB pulse communication. [ABSTRACT FROM AUTHOR]

To solve the problem that the parameter estimation of linear frequency modulation-pseudo random binary codes(LFM-PRBC) signal requires a large amount of computation in current algorithms, a fast parameter estimation algorithm which uses dechirp and fractional Fourier transform (FRFT) is proposed. Firstly, the dechirp is used to obtain the rough estimation of chirp rate which can determine the angle of rotation, and the rough estimation of symbol width is achieved by FRFT. And then, the exact value of chirp rate is estimated from the second dechirp based on the delay of the signal. Finally, through the second FRFT the exact value of symbol width and the initial frequency are obtained. The proposed algorithm has not only low computation complexity but also high estimation accuracy and strong ability of immunity to noise. The effectiveness of this algorithm is verified by simulation. [ABSTRACT FROM AUTHOR]

This is the latest study on the tracking of the implications of the dynamic digital revolution in the new global environment. The series of studies began in 2006 as we attempt to understand how digital technology affects lifestyles and the way we conduct business. Digital revolution is reshaping lifestyles and work schedules all over the world. Internet technology is speeding up management methods and revolutionizing communications. Virtual offices have become commonplace as electronic mail messages and mobile phones become regular companions. The digital revolution is radically changing the ways individuals and organizations interact. Every minute of the waking hours of many professionals is potentially open for business. The economic impact is huge as global productivity keeps rising in geometric proportions. It is argued that this digital environment calls for new approaches to managing work-life and lifestyles, in general. [ABSTRACT FROM AUTHOR]

Recursive system convolutional code (RSC code) is the commonly used encoding form of Turbo sub-encoders. For the blind recognition problem of (n,1,m) RSC code, a method based on Walsh-Hadamard transform is proposed. Firstly, code parameters are estimated by analyzing matrix constructed by the received codeword. Then, the mathematical recognition model is derived according to RSC code's characteristics, the specific implementation steps are provided and the principle of the method is introduced. The simulation results from Matlab show that the performance of the method is obviously more excellent in comparison with other methods. The recognition probability reaches 90% when bit error rate(BER) is as high as 10-2,which indicates the great significance of the proposed method for further research on Turbo code. [ABSTRACT FROM AUTHOR]

Despite of widespread use of new digital wireless communications, the radiated immunity test based on IEC 61000-4-3 only has been performed with using amplitude modulation (AM) signal. In this study, we have analyzed the radiated immunity test method that is going on recent standardization activity to investigate close proximity fields from radio frequency (RF) wireless communications and have investigated the impact of digitally modulated signals. The results show that the devices were influenced much more by digital modulation signal than by AM or pulse modulation (PM) signal. Also it shows that we need to investigate the depth research on radiated immunity testing for the environment of modern communication technology. [ABSTRACT FROM AUTHOR]

This paper introduce a new approach to FPGA implementation of synchro to digital converter using Co-ordinate Rotation Digital Computer CORDIC algorithm. This algorithm was the best replacement of analog conversion system by the high resolution digital. CORDIC algorithm used for the fast calculation of elementary functions like multiplication, division, trigonometric functions. The approach is based on receiving the synchro signals S1, S2, and S3 from the synchro motor, and converts them to two perpendicular signals sin signal and cosine signal using solid state Scott-t transformer. Then the a CORDIC circuit receive this signals after converting them to digital and produce the azimuth angle in digital format. This prototype of hardware implementation of CORDIC algorithm used Spartan-III series FPGA, with constraint to area efficiency and throughput architecture. The prototype results show that the conversion time is less than 1 µs which is suitable for real time applications in radar and missile control applications. [ABSTRACT FROM AUTHOR]

Clock synchronization is a very important issue for the applications of wireless sensor networks. The sensors need to keep a strict clock so that users can know exactly what happens in the monitoring area at the same time. This paper proposes a novel internal distributed clock synchronization solution using group neighborhood average. Each sensor node collects the offset and skew rate of the neighbors. Group averaging of offset and skew rate value are calculated instead of conventional point-to-point averaging method. The sensor node then returns compensated value back to the neighbors. The propagation delay is considered and compensated. The analytical analysis of offset and skew compensation is presented. Simulation results validate the effectiveness of the protocol and reveal that the protocol allows sensor networks to quickly establish a consensus clock and maintain a small deviation from the consensus clock. [ABSTRACT FROM AUTHOR]

This paper considers the detection of coded phase-shift keying signals subjected to additive white Gaussian noise and oscillator phase noise. We propose a detector that partitions the received frame into smaller blocks and models the unknown phasor variations over each block as a truncated discrete cosine transform (DCT) expansion. Detection and decoding are iteratively performed between a soft-input soft-output (SISO) demodulator, a SISO demapper, and a SISO decoder based on the sum–product algorithm and the factor graph framework, whereas the expectation–maximization algorithm is used in the demodulator for the DCT coefficients estimation. The resulting demodulator is shown to have an excellent performance/complexity tradeoff and to be well-suited for parallel processing on multiple cores. [ABSTRACT FROM PUBLISHER]

In this paper, we propose a new method for inter-carrier interference (ICI) mitigation in orthogonal frequency-division multiplexing (OFDM) systems. The proposed approach views the signal reconstruction problem at the receiver end as an integer least squares (ILS) problem, and uses a recently developed spectral approach called sequential probabilistic ILS (SPILS) to solve it. The proposed approach outperforms other state-of-the-art approaches while having the same computational complexity. In addition, we present a novel extension to the SPILS scheme that allows the generation of soft decisions (for communication systems which use soft-decision decoding). The use of soft-decision decoding (naturally) brings significant improvement in the detection reliability, and we show that the proposed method again outperforms other state-of-the-art approaches. To better address the tradeoff between performance and complexity, we first suggest a novel method to reduce the number of matrix inversions required and hence, to reduce the implementation complexity without any degradation in performance. We also introduce a novel low complexity scheme termed Quick SPILS (QSPILS) in which we lose a little in detection reliability, but significantly reduce the implementation complexity. [ABSTRACT FROM PUBLISHER]

The gap waveguide technology was recently introduced as an alternative to hollow waveguides and substrate integrated waveguides for millimeter-wave applications. This paper presents the design of a 4\times4 planar dual-mode horn array with low loss corporate feed network realized by using an inverted microstrip gap waveguide. The dual-mode horns are compact and designed to reduce the power losses in grating lobes. It is because the diameters of the horn apertures are larger than two wavelengths to allow more space for the feed network and thereby lower conductive losses. The measurements show very good agreement with simulations, with 10% bandwidth of the return loss, 25 dBi realized gain and about 60% aperture efficiency. [ABSTRACT FROM PUBLISHER]

This article investigates the development of the concept of museum communication in a Danish cultural political context from 2006 until 2013 and the practical consequences a changed interpretation of the concept has for the Danish state-owned and state-supported museums. The main argument is that the concept of cultural communication, specifically concerning museums, has undergone a transformation towards having a digital content of meaning in recent years. And furthermore: that the meaning ascribed to the concept has practical impact. The increased attention paid to communication, particularly digital communication, in the tasks of the museums, is redistributing the museums' resources, foci and priorities. This call for a more thorough discussion of what museums must and can be in the future -- and not least for whom. [ABSTRACT FROM AUTHOR]

In order to implement the concept of educational principle of a research university and the training objectives of international elite, construct open teaching patterns, adapt to the evolving needs of personnel training, a digital interactive system of cooperation education of China and Russia was constructed in biological foundation experiment center of Heilongjang university. Modern information technology was applied into personnel training classrooms of internationalization of higher education through microscope systems, image processing systems, multimedia projection systems, voice answering system and application software systems. The communication of teachers and students was more accurate and convenient by using Knob function of LED pointer system and convenient manipulation interface. It is necessary to apply Motic digital interactive system for combination culture between China and Russia and interactive multimedia experimental teaching in biological foundation experiment center. Application of modern multimedia technology and high-tech means has enriched practice of teaching content, improved the efficiency and effectiveness of experimental teaching, and achieved domestic and international sharing of information resources. [ABSTRACT FROM AUTHOR]

This article explores the communicative relationship between civic organizations and young citizens as a clue to understanding the potential for youth re-engagement through digital communication. It develops a framework of two ‘civic information styles’ that contrasts the expectations of information in the mass media era with those emerging today, and proposes that one source of contemporary disconnect may be that many civic groups remain entrenched in a mass media information paradigm—and so fail to communicate in ways that resonate with young people. Existing literature suggests that recently created, online organizations will be most likely to embrace a newer, more youth-friendly communication style; those organizations working within the formal political realm may be most reticent. A study of 60 organizations’ communications through Facebook mainly confirms these expectations, but low levels of youth-friendly communications across the sample raise doubts about the likelihood of a civil society resurgence through social media. [ABSTRACT FROM PUBLISHER]