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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]

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]

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 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]

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]

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]

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]

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]

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]

In this paper, we identify how and why digital media production can contribute to the active participation of children in education and also consider how much of the existing work in this area is framed as a ‘miraculous’ answer to educational challenges without critical interrogation of either the process or product. To begin, we identify some of the prominent research and issues that have emerged from work of this kind and discuss the barriers to accessing equitable education in relation to new media production projects with kids. We discuss the changing state of knowledge production and communication in a new media world and address the place of literacy in this changing educational context. Following this, we present one example of a media production club and the way we look at this work to value students' productions in a way that differs from other research of this kind. [ABSTRACT FROM PUBLISHER]

This paper proposes a robust model for the accurate behavioral modeling and digital predistortion (DPD) of wideband radio-frequency power amplifiers (PAs). It is constructed using a complexity-reduced generalized memory polynomial (MP) (GMP) (CR-GMP) connected with a nonlinear memory effect (NME) subblock in parallel. The CR-GMP is a complexity-reduced but accuracy-degraded version of the conventional GMP, and its performance is augmented by the extra NME subblock. Hence, the proposed model is termed as augmented CR-GMP (ACR-GMP). The resultant ACR-GMP model can achieve comparable performance as the GMP model, but with much fewer coefficients and lower complexity. Its performance is experimentally assessed both in forward modeling and DPD linearization. Comparisons are conducted between the ACR-GMP model and some state-of-the-art models, such as the MP, the PLUME, and the GMP. Experimental results have been given for a 1.9-GHz 35-W peak-power GaN Class-AB PA driven by two signal scenarios: a 15-MHz bandwidth long-term-evolution signal and a 20-MHz bandwidth wideband-code-division-multiple-access 1001 signal (with the middle two carriers OFF). All the results show that the ACR-GMP model outperforms both the MP and the PLUME models in terms of performances and the GMP model in terms of complexity (at comparable performances). [ABSTRACT FROM PUBLISHER]

In transition to digital age, enormous challenges are posed to all the heritage institutions, including museums. Digitization of records such institutions keep in their funds is becoming more and more one of their everyday tasks, and at the same time also a manner for presenting and making available to the public use the valuable collections stored in them. This paper presents a survey conducted in March 2012 in Croatian museums about the participation of Croatian museums in digitization procedures that is in presenting the collections of Croatian museums in a digital environment. [ABSTRACT FROM AUTHOR]

This paper investigates the impact of an errorprone buffer memory on a channel decoder as employed in modern digital communication systems. On one hand this work is motivated by the fact that energy efficient decoder implementations may not only be achieved by optimizations on algorithmic level, but also by chip-level modifications. One of such modifications is so called aggressive voltage scaling of buffer memories, which, while achieving reduced power consumption, also injects errors into the likelihood values used during the decoding process. On the other hand, it has been recognized that the ongoing increase of integration density with smaller structures makes integrated circuits more sensitive to process variations during manufacturing, and to voltage and temperature variations. This may lead to a paradigm shift from 100%-reliable operation to fault tolerant signal processing. Both reasons are the motivation to discuss the required co-design of algorithms and underlying circuits. For an error-prone receive buffer of a Turbo decoder the influence of quantizer design and index assignment on the error resilience of the decoding algorithm is discussed. It is shown that a suitable design of both enables a compensation of hardware induced bits errors with rates up to 1% without increasing the computational complexity of the decoder. [ABSTRACT FROM AUTHOR]

Digital journals have been widely adopted by academic researchers and have nearly replaced printed journals in many contexts. The adoption of digital books is accelerating. The transition to digital information has changed information workflows of researchers by transforming the methods they use to find, store, retrieve, and use information from monographs, journals, and other sources. It has also changed the needs and expectations of scholars in relation to research information. To investigate these changes, 45 researchers in science, medicine, engineering, social sciences, and humanities at Stanford University were interviewed regarding information workflow and preferences. Results are compared with the findings of the e-Journal User Study (eJUSt), completed in 2002. [ABSTRACT FROM AUTHOR]

A novel approach for all-optical digital encoder for both binary-to-gray code and gray-to-binary code have been proposed. Design is based on the basic concept of digital encoder using the exclusive OR (XOR) addition. The XOR gate used in these encoders has been implemented using differential phase modulation between two arms of the Mach-Zehnder interferometer (MZI), in which a semiconductor optical amplifier is placed symmetrically in both arms of MZI. For the most severely degraded output bit, i.e., least significant bit for gray-to-binary encoder, the extinction ratio obtained is 2.35 while the minimum bit error rate is zero at 10 GB/s. For the second most significant bit of gray-to-binary encoder and for all the three bits except the most significant bit of binary-to-gray encoder, the extinction ratio obtained is around 27 dB. For the most significant bit, as input and output bits are same, the extinction ratio is very high, approaching infinity. [ABSTRACT FROM AUTHOR]

Digital public sphere is immersed in the present conjuncture of accelerated transformation and probable rupture, which certainly will affect the way we exercise our citizenship in contemporary times. This social and political tsunami is partly based on the change of paradigm of Web 2.0 or Social Web to Web 3.0 or Semantic Web. To clarify such a process, this paper discusses some of the key issues and theoretical positions on public space, from seminal Habermas's perspective to new problematics raised by the networked society. The author suggests the construction of a Sociological Ontology of Social and Semantic Web, based on a Semantic-Logical Sociology and Methodology. These procedures are applied through the analysis and hermeneutics of a Wikipedia page entitled 'Web 2.0', where sociological experimental tools are used, as Semantic-Logical fields, trees and networks, central and peripheral concepts, and trichotomies. [ABSTRACT FROM AUTHOR]

Thinking communication in the actual contexts involves the assumption of complex scenarios occupied by phenomena and transformations, whose permanent technological and mediatic progress develop communicative/creative processes that allow the arising of innovative communicative structures, which promote debates about an imminently digital culture. The new dynamics whose aesthetic and communicative characteristics take shape from the use of information and communication technology (ICT) trace new ways of understanding, interacting, and training professionals in the field of communication. This article presents the results of a research whose main question was: ¿what is the conception of digital communication and digital aesthetic assumed by teachers who impart lessons related to information and communication technology in the academic programs of Social Communication and Journalism, in the Department of Valle del Cauca (Colombia)? [ABSTRACT FROM AUTHOR]

The article considers the impact of information technology on the operations of the Federal Institute of Industrial Research, Oshodi (FIIRO), a research institute of the Ministry of Science and Technology which conducts research on and assists in development of technological transfers to sectors of that country's economy. The impact of the introduction of computers and Internet access for all of the institute's personnel on its activities is examined. A survey of employees of the institute found widespread ownership and use of microcomputers and Internet use, but that the bandwidth available to the institute had created a significant problem with the speed of Internet access and operation.

The article introduces papers included in the special section forum in "Communication Quarterly," with topics such as collaboration across disciplines, digital health production in the classroom and the role of pathos and collective affiliations in understanding health and producing progressive health messages.

Scalable representation of visual signals, such as image and video signals, has become a subject of active research since early 1980s. Scalability allows the adaptation of the bit rate and/or the resolution of the transmitted data to the network bandwidth and/or the rendering capability of the receiving device. For many years, spatial scalability has been achieved through wavelets, but recently the Laplacian pyramid (LP) has become an alternative choice because of reduced aliasing in the lower resolutions. In this paper, we focus on the coding efficiency of the LP with a view to transmitting it over a communication channel. In particular, we aim to improve the compression efficiency of the LP detail layers through improved interlayer prediction and orthogonal spatial transforms. First, we consider an LP in the open-loop configuration and propose to improve its rate-distortion performance by compressing it to a critically sampled representation. We derive four different orthogonal spatial transforms from the upsampling and downsampling filters that can achieve this representation, and apply them on the detail layers. The application of these transforms to the detail layers renders a fixed number of transform coefficients either zero or redundant, thus making their transmission unnecessary. Then we consider the compression of an LP in the closed-loop configuration through similar spatial transforms. Because of the introduction of quantization in the prediction loop, these spatial transforms applied on the detail layers do not produce the same number of zero or redundant transform coefficients as in the open-loop case. Nevertheless, the insight obtained from the open-loop coding leads us to enhance the interlayer prediction, and the subsequent application of the spatial transforms to the new detail layers aims to achieve better energy compaction. [ABSTRACT FROM AUTHOR]

Digital circuits implemented in CMOS technology have been the workhorses of high performance computer processors for more than a decade, following Moore's law with exponentially increasing integration and performance. Driven by lower cost, increasing performance, and mixed-signal benefits, CMOS technology also has found increasing use in analog, and more recently, RF applications. Now, with transistor performance still improving, wires are becoming the limiting factor for speed and performance by imposing limits on communication bandwidth and latency between processing cores and memories, both off- and on-chip. Communication and circuit techniques, developed mainly for narrow band-wireless RF communication can help increase the wired communication speed in digital systems. This approach, dubbed RF Interconnect (RF-I), picks up speed for on-board and on-chip applications, changing the communication paradigm from the old parallel unidirectional time-shared bus to new transmission lines enabling reconfigurable communication using both frequency and code division multiple access techniques. [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.)

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]

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.

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]

Copyright of Journal of Konbin is the property of Air Force Institute of Technology (Instytut Techniczny Wojsk Lotniczych) 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.)

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]

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]