Shared Medium Research Articles

Compartilhamento de mídia e preferência eleitoral no Twitter: uma análise de opinião pública durante as eleições de 2014 no Brasil

This research analyzed a series of tweets published during the second round of the 2014 presidential elections in Brazil, in order to investigate the shared media and the electoral preference of citizens on Twitter. To that end, we developed a methodology and applied a manual analysis of content and sentiment to a sample of 1129 tweets (N = 1129) published at the time in order to identify which media were shared in each of the publications and the electoral preference between the two candidates expressed in the tweet. Our findings reinforce the idea that mainstream media is predominantly share don social media, but also that there is considerable presence (40%) of what we call “complementary media,” which offer more partybased content during the campaign. Furthermore, both “audiences” in the analysis shared the same proportion of mainstream and complementary media, which denotes a pattern to be tested in future studies.

Visible light communication – An architectural perspective on the applications and data rate improvement strategies

AbstractDemand for bandwidth hungry applications and mobile services is pushing an unquenchable need for wireless capacity. Existing radio frequency networks are characterized by shared medium, inadequate spectrum, and restricted user capacity. Solid state lighting is modernizing indoor as well as outdoor illumination. The capability of quick switching of light emitting diode makes them superior to other lighting sources enabling simultaneous use as a communication and illumination device. Visible light communication (VLC) using light emitting diodes is an attractive approach for many networking scenarios and is considered as a complementary technology for future heterogeneous wireless networks.This article presents an architectural perspective on the applications and data rate improvement strategies. A wide range of VLC applications have been investigated, comparison has been drawn with radio frequency, and generalized network architecture is also proposed. Numerous applications of VLC are data rate intensive, so data rate improvement approaches have also been studied. At the end, a lucid conclusion is drawn about the applicability, acceptability, and utilization of VLC and co‐VLC–based systems.

Causal language and strength of inference in academic and media articles shared in social media (CLAIMS): A systematic review.

BackgroundThe pathway from evidence generation to consumption contains many steps which can lead to overstatement or misinformation. The proliferation of internet-based health news may encourage selection of media and academic research articles that overstate strength of causal inference. We investigated the state of causal inference in health research as it appears at the end of the pathway, at the point of social media consumption.MethodsWe screened the NewsWhip Insights database for the most shared media articles on Facebook and Twitter reporting about peer-reviewed academic studies associating an exposure with a health outcome in 2015, extracting the 50 most-shared academic articles and media articles covering them. We designed and utilized a review tool to systematically assess and summarize studies’ strength of causal inference, including generalizability, potential confounders, and methods used. These were then compared with the strength of causal language used to describe results in both academic and media articles. Two randomly assigned independent reviewers and one arbitrating reviewer from a pool of 21 reviewers assessed each article.ResultsWe accepted the most shared 64 media articles pertaining to 50 academic articles for review, representing 68% of Facebook and 45% of Twitter shares in 2015. Thirty-four percent of academic studies and 48% of media articles used language that reviewers considered too strong for their strength of causal inference. Seventy percent of academic studies were considered low or very low strength of inference, with only 6% considered high or very high strength of causal inference. The most severe issues with academic studies’ causal inference were reported to be omitted confounding variables and generalizability. Fifty-eight percent of media articles were found to have inaccurately reported the question, results, intervention, or population of the academic study.ConclusionsWe find a large disparity between the strength of language as presented to the research consumer and the underlying strength of causal inference among the studies most widely shared on social media. However, because this sample was designed to be representative of the articles selected and shared on social media, it is unlikely to be representative of all academic and media work. More research is needed to determine how academic institutions, media organizations, and social network sharing patterns impact causal inference and language as received by the research consumer.

Mathematical and simulation analysis of contention resolution mechanism for IEEE 802.11ah networks

IEEE 802.11ah Task Group has introduced group-based contention mechanism called Restricted Access Window (RAW) for accessing the shared medium. The RAW mechanism is an initial solution to control the collision that occurs due to the heavy contention in large networks. The Distributed Coordination Function (DCF) is a contention-based medium access method that uses Binary Exponential Backoff (BEB) to resolve contention among the stations inside the RAW group. As mentioned in several literatures, BEB suffers from high probability of collisions. This problem is mitigated through an efficient BO algorithm with appropriate integer sequences for calculating new Contention Window (CW) without any additional control overheads and complex computations. An analytical model is developed for computing saturated throughput, attained by the proposed algorithm. A comprehensive simulation is also carried out in NS3 network simulator with different packet sizes. It is observed from analytical and simulation results that, the proposed backoff algorithm outperforms BEB in terms of saturated throughput, packet delivery ratio, packet loss ratio and delay.

Try-once-discard scheduling for stochastic networked control systems

ABSTRACTIn practical networked control systems (NCS), such as smart grids, cooperative robotics, and sensor networks, often multiple control applications share a communication infrastructure, requiring a smart and efficient scheduling mechanism to coordinate the access to the capacity-limited communication medium. In this article we consider the problem of event-based scheduling design for NCSs consisting of multiple control loops over a shared communication medium. We extend the notion of Try-Once-Discard (TOD), which is one of the basic deterministic event-based scheduling protocols for resource constrained NCSs, to the case of multiple stochastic control systems coupled via a shared communication medium subject to capacity limitation and stochastic packet delivery failure. Showing that the overall network-induced error is a homogeneous Markov chain in our stochastic set-up, we first study stability properties of such networked systems under the TOD scheduling scheme employing the concepts of stochastic stability. Then, we derive sufficient stability conditions under the TOD rule assuming that the communication channel is not ideal, i.e. a scheduled data packet for transmission might be lost in the communication channel with a non-zero probability. Furthermore, we derive analytic performance bounds by finding uniform upper-bounds for an average quadratic cost function. The numerical simulations are performed for variety of system parameters and NCS set-ups to strengthen our stability claim as well as illustrating performance bounds. Additionally, we show that the TOD scheduling rule outperforms the conventional time-triggered, and uniform and non-uniform random channel access arbitration mechanisms, in terms of efficient coordination of channel access in stochastic NCSs.

SDPR: Improving Latency and Bandwidth in On-Chip Interconnect Through Simultaneous Dual-Path Routing

Networks-on-chips (NoCs) are gaining in popularity as replacement for shared medium interconnects in chip-multiprocessors (CMPs) and multiprocessor systems-on-chips, and their performance becoming essential to system performance. There have been emerging studies to achieve better power/energy efficiency without performance degradation on NoCs. However, there are still non-negligible latency issues caused by the mechanism of power efficient approaches. To alleviate the latency problem and to transfer data efficiently with the high utilization of interconnect resources, we propose an on-chip network architecture that improves latency and bandwidth. Increasing the data/link widths across the network may considerably resolve this problem but is a costly proposition both in terms of device area and of power. Alternatively, we propose a dual-path router architecture that efficiently exploits path diversity to attain low latency without significant hardware overhead. By: 1) doubling the number of injection and ejection ports; 2) splitting packets into two halves; 3) recomposing routing policy to support path diversity; and 4) provisioning the network hardware design, we can considerably enhance network resource utilization to achieve much higher performance in latency. The proposed simultaneous dual-path routing (SDPR) scheme outperformed the conventional dimension order routing (DOR) technique across synthetic workloads by 31%–40% in average latency and up to a 100% improvement in throughput performance running on a 49-core CMP. Our synthesizable model for the SDPR router and network provides accurate power and area reports. According to the synthesis reports, SDPR incurs insignificant overhead compared to the baseline XY DOR router.

Paid, Earned, Shared and Owned Media From the Perspective of Advertising and Public Relations Agencies: Comparing China and the United States

ABSTRACTDespite the existence of the “great firewall,” advertising and public relations practitioners in China, much like in the United States, are embracing and enacting social media and digital strategies on behalf of their clients. In this study, we conducted 42 in-depth interviews with advertising and public relations practitioners in the United States and mainland China to explore how emerging media and integrated marketing communication (IMC) are impacting advertising and public relations agencies in the two countries. This cross-cultural comparison revealed several critical insights, which were examined through the lenses of IMC and dimensions of culture. We found that emerging media lead to converging trends in various aspects of agency performance. The blurring of paid, earned, shared, and owned media (PESO) was evidentially observed in how executives of both countries defined and used media. Chinese agencies were media agnostic, concerned more with effectiveness of media practices. The U.S. agencies embraced collaboration and information technology better compared to their Chinese peers. This research contributes to the body of knowledge in strategic communication via providing empirical evidence of how Chinese and U.S. agencies coordinate IMC and perceive PESO media relative and in response to emerging media practices.

TDA-MAC: TDMA Without Clock Synchronization in Underwater Acoustic Networks

This paper investigates the application of underwater acoustic sensor networks for large scale monitoring of the ocean environment. The low propagation speed of acoustic signals presents a fundamental challenge in coordinating the access to the shared communication medium in such networks. In this paper, we propose two medium access control (MAC) protocols, namely, Transmit Delay Allocation MAC (TDA-MAC) and Accelerated TDA-MAC, that are capable of providing time division multiple access (TDMA) to sensor nodes without the need for centralized clock synchronization. A comprehensive simulation study of a network deployed on the sea bed shows that the proposed protocols are capable of closely matching the throughput and packet delay performance of ideal synchronized TDMA. The TDA-MAC protocols also significantly outperform T-Lohi, a classical contention-based MAC protocol for underwater acoustic networks, in terms of network throughput and, in many cases, end-to-end packet delay. Furthermore, the assumption of no clock synchronization among different devices in the network is a major advantage of TDA-MAC over other TDMA-based MAC protocols in the literature. Therefore, it is a feasible networking solution for real-world underwater sensor network deployments.

Tension-loaded bone marrow stromal cells potentiate the paracrine osteogenic signaling of co-cultured vascular endothelial cells.

ABSTRACTCo-culture of bone marrow stromal cells (BMSCs) and vascular endothelial cells (VECs) is a promising strategy for better osteogenesis and pre-vascularization in bone tissue engineering. Recent reports have shown that mechanical stretching further promotes osteogenesis in BMSC/VEC co-culture systems, but the underlying mechanism of this process remains unclear. In this study, noncontact co-cultures of rat primary BMSCs and VECs were employed to interrogate paracrine cell-to-cell communications in response to tension. Exposure of VECs to 6% tension for 48 h elicited neither ALP activity nor mRNA expression of OCN and OPN in BMSCs incubated in a shared culture medium. Instead, BMSCs subjected to tension induced robust VEGF release, and its conditioned medium enhanced the proliferation and tubular formation of VECs with a concurrent increase in BMP-2 and IGF-1 production. Conditioned medium from activated VECs in turn promoted expression of osteogenic genes in BMSCs, followed by an increase in matrix mineralization. The addition of VEGF-R inhibitor Tivozanib to these systems abrogated the tension-induced paracrine effects on VECs and subsequently impaired BMSC osteogenesis. These results clearly demonstrate that the response of BMSCs to tension potentiates paracrine osteogenic signaling from VECs; this positive feedback loop is initiated by VEGF release.

PENERAPAN MODEL PEMBELAJARAN THINK PAIR SHARE DAN MEDIA VIDEO DAKWAH UNTUK MENINGKATKAN KETERAMPILAN MENULIS PARAGRAF PERSUASIF BERMUATAN PENDIDIKAN KARAKTER PADA SISWA KELAS X MA

The purpose of this research is (1) to describe the improvement of writing skill of persuasive writing of class X student of MA Al Anwar Mranggen Demak afterapplied Think Pair Share model and video media of da�wah with charactereducation, (2) to describe the improvement of learning attitude of grade X MA AlAnwar Mranggen Demak after following the writing of persuasive paragraph withThink Pair Share model and video media da�wah with character education, and(3) to describe the increase of learning motivation of grade X MA Al AnwarMranggen Demak after following lesson writing persuasive paragraph with ThinkPair Share model and video media of da�wah Charged character education. Thisresearch is a quantitative and qualitative research. Quantitative research that is in the form of value analysis from test result writing persuasive paragraph.Qualitative research in the form of data analysis from nontes result throughobservation, questionnaire, interview, and documentation. Based on the result of research that has been done, it can be seen that the skills of students of class X MA Al Anwar Mranggen Demak in writing persuasive paragraphs have increased. This can be known through the writing of a persuasive paragraph in each cycle. In prasiklus students get a grade point average of 43,5. In the first cycle the average grade of the students increased to 61,17. In cycle II the students get the average grade of 64,83 and on the third cycle the average grade of the students to 78. It proves that the writing of the persuasive paragraph of the students has increased in cycle I, cycle II, and cycle III.

A REVIEW OF MULTIHOP BASED MEDIUM ACCESS CONTROL (MAC) PROTOCOL TO TACKLE BOTH MULTIPLE ACCESS AND MULTIHOP ISSUES IN WIRELESS MESH NETWORK (WMN)

Multihop WMN plays an important role in the next-generation wireless communication. It promised a solution to provide ubiquitous wireless access at low cost and with architecture that easy to be deployed and maintained. A big challenge in designing WMN is to utilize the shared medium, the wireless communication channel, effectively. MAC protocol, the shared medium access controller, therefore plays a critical role in the channel utilization. The better the channel is utilized in WMN, the better is the performance of the WMN. One of the techniques to improve channel utilization is by enabling the concurrent transmission and providing an efficient forwarding operation. However, the existing IEEE 802.11 MAC does not supports those operations in WMN thus degrades the throughput significantly. To date, various multihop based MAC protocols was developed and proposed by researchers with the aim to regulate and solve access issues among all radio nodes in the network. This article presents an exhaustive survey of multihop based contention MAC protocols that proposed to solve exposed node and forwarding issues in multihop WMN. Besides that, the comparison, their operations, advantages and disadvantages of all identified MAC protocols also will be explained and presented in this article.

Clinical evaluation of two generations of time lapse imaging systems

Time lapse monitoring of embryos during culture is being used increasingly to achieve optimal culture conditions, improved embryo selection, quality control, and more efficient workflow in the laboratory. Since 2015, two EmbryoScope™ (ES-D) devices, each with a capacity to monitor up to 12 embryos from 6 patients have been used in our clinic. In order to allow for time lapse monitoring during the entire incubation period for all our patients, we installed five units of the new EmbryoScope+™ (ES+) device in 2017. One ES+ unit can monitor up to 16 embryos from a total of 15 patients simultaneously. Due to the increased capacity of the ES+, the number of “door” openings of the incubator have increased compared to the ES. However, the ES+ incubator has also been re-configured so that only the embryo slides taken out of the incubator are ejected from the controlled environment, leaving remaining slides concealed inside the incubator. One additional difference between the two systems is that the embryos in the dish for ES+ share media overlay, whereas, the embryos in the ES dish are completely isolated from each other. In this study, we compared outcomes between the two incubator types as we migrated from the ES-D to the ES+. A prospective study We targeted 776 mature ova in 73 cycles from which at least six oocytes were retrieved between January and February 2017 for investigation. After insemination, embryos from each patient were allocated to two groups and incubated in an ES-D (ES group) or an ES+ (ES+ group). We compared fertilization rate, cleavage rate, Day-3 good-quality embryo rate, Day-5 blastocyst formation rate, Day-5 good-quality blastocyst rate, and Day-6 blastocyst formation rate between the ES-D and ES+ groups. Our findings revealed for the ES-D versus the ES+ group a fertilization rate of 85.8% versus 83.0%, cleavage rate 100% versus 97.5%, Day-3 good-quality embryo rate 70.6% versus 74.5%, Day-5 blastocyst formation rate 62.2% versus 69.4%, Day-5 good-quality blastocyst rate 37.5% versus 44.2%, and Day-6 blastocyst formation rate 9.8% versus 5.6%, respectively. There was no significant difference between the two groups in these parameters. The outcomes with the two time-lapse incubation and imaging systems showed no statistical difference in the present study; even though, the new ES+ device tended to yield higher blastocyst formation than the ES-D. The ES+ provides an incubation environment that is at least equivalent or superior to that of the ES-D, ES-D occupied area per patient was 562.8 cm2 per patient and , ES + was 220.0 cm2 per patient, and has more than double the capacity of the ES-D. Thus, the ES+ is shown to be a highly attractive upgrade for a busy lab such as ours.

The Backbone Packet Radio Network coloring for Time Division Multiple Access link scheduling in Wireless Multihop Networks

A radio network consists of a set of transceiver nodes in space that communicate using broadcast radio. Since communication is done over a shared medium, transmissions are subject to collisions. Different Medium Access Control techniques are used to avoid such collisions and subsequent data loss. In this article, we study Time Division Multiple Access link scheduling in Wireless Multihop Networks. We generalize the packet radio network (PRN)‐coloring model that was used in previous works to obtain the Backbone PRN (BPRN)‐coloring. The BPRN‐coloring captures the fact that typically only a subset of links need to be scheduled, corresponding to the backbone network. We study the BPRN‐coloring and the corresponding BPRN‐chromatic index considering a rooted tree as backbone, motivated by applications in Wireless Sensor Networks. The BPRN‐chromatic index is determined when the whole graph is either a complete graph or a cycle, and we give partial results in the case of a bipartite graph. We show that determining the BPRN‐chromatic index is NP‐hard even when the network graph is bipartite, and the backbone is an oriented tree toward a root vertex. Finally, we model a ring topology as the power of a cycle graph and give an upper bound on the BPRN‐chromatic index. © 2017 Wiley Periodicals, Inc. NETWORKS, Vol. 71(4), 403–411 2018

Interference-Aware Wireless Network-on-Chip Architecture Using Directional Antennas

Wireless Network-on-Chip (WiNoC) has been recently introduced for addressing the scalability limitations of conventional multi-hop NoC architectures. Existing WiNoC architectures generally use millimeter-wave antennas without significant directional gains, along with token passing protocol to access the shared wireless medium. This limits the achievable performance benefits since only one wireless pair can communicate at a time. It is also not practical in the immediate future to arbitrarily scale up the number of non-overlapping channels by designing transceivers operating in disjoint frequency bands in the millimeter-wave spectrum commonly adopted for on-chip wireless interconnects. Consequently, we explore the use of directional antennas whereby multiple wireless interconnect pairs can communicate simultaneously. However, concurrent wireless communications can result in interference. This can be minimized in NoC by optimal placement of wireless interfaces (WIs) to maximize performance while minimizing interference. To address this, we propose an interference-aware WIs placement algorithm with routing strategy for WiNoC architecture by incorporating directional planar log-periodic antennas (PLPAs). This directional wireless network-on-chip (DWiNoC) architecture enables point-to-point links between transceivers and hence multiple wireless links can operate at the same time without interference.

Optimized tuning of contention window for IEEE 802.11 WLAN

In wireless networks, the size of Contention Window (CW) plays a vital role as it changes the throughput and delay of the networks considerably. The proposed Collision Ratio based BackOff (CRBO) algorithm uses collision ratio to suggest CW updation after the successful and unsuccessful transmission events. This leads to proper scheduling of transmission when more than one node attempt to capture the shared medium. The strength of the proposed algorithm is analyzed using NS2 simulator in terms of throughput, delay, packet loss and fairness. The simulation results prove that the proposed algorithm outperforms the existing algorithms under heavy and low traffic in random and grid topology.Keywords: Wireless networks, contention window, collision rate, backoff, NS2

Efficient Monitoring of ST2059-2 Based Time Transfer Performance

In any mission critical-broadcasting application, reliable synchronization is mandatory. For traditional black burst or trilevel-based synchronization, redundant sync signal generators are used, whose quality is monitored together with their respective switch-over units. To make the best use of a single shared communication medium within an all-IP studio, synchronization is accomplished using the IEEE 1588 Precision Time Protocol (PTP). Although multiple sync sources are deployed for redundancy purposes, the monitoring of their availability and precision is not sufficient to guarantee the defined level of accuracy. Additional data has to be gathered and analyzed by every node prior to deployment and as part of its ongoing operation. After briefly describing the main effects influencing PTP accuracy, several monitoring methods using both in-band and out-of-band are described, including how this benefits operations in the broadcast plant. Finally, we verify their respective merits through a series of measurements in a datacenter class multihop network architecture.

A Survey of Cross Layer Design in Wireless Networks for Joint Optimization of Multimedia Transmission

Optimization of wireless network architecture plays a vital role in achieving maximum network capacity. Shared wireless media in the presence of multiple users and multiple applications need to be used optimally to enhance satisfaction of the users. Especially, mobile multimedia applications demand wireless networks to allocate resources optimally and adapt to environment dynamics. Cross Layer Design (CLD) is a paradigm to optimize traditional layers of communication network architecture. As far as video streaming is considered over wireless networks, it is challenging to achieve Quality of Experience (QoE) and Universal Multimedia Access (UMA), which addresses the problem of delivering multimedia resources under different conditions. In this paper, we focus on finding insights from the present state-of-the-art of CLD for optimization of multimedia transmission over wireless networks. It throws light into different layers and the joint optimization possibilities to leverage multimedia content dissemination in wireless networks. The insights of research findings of this paper provide valuable knowhow on joint optimization of multimedia transmission over wireless networks.

Is It Really That Funny? Laughter, Emotional Contagion, and Heuristic Processing During Shared Media Use

ABSTRACTWhen people use humorous media content, their behavior and assessments of the content may depend on the emotional expressions (e.g., laughter) of those around them. In a laboratory experiment in which 80 participants watched a movie clip with a confederate who either laughed or remained silent, we identified two parallel processes. The confederate’s laughter induced behavioral responses in our participants (laughing or smiling). Through those responses, a corresponding appraisal of the media content was generated: The content was rated funnier in comparison to situations in which the confederate did not laugh. This effect corresponds to emotional contagion processes and was especially pronounced in introverts. Additionally, participants who were low in conscientiousness directly elevated their funniness ratings (more than their own emotional expressions would suggest) when the confederate laughed. Those who were high in conscientiousness, however, lowered their ratings of the content’s funniness in the presence of a laughing confederate. This finding suggests the existence of an additional cognitive process that links confederate’s laughter and participant’s content ratings beyond automatic contagion. Participants with low conscientiousness use the confederate’s laughter as a heuristic cue for the content’s funniness, while highly conscientious participants discount the confederate’s laughter as a cue for content funniness.

Networked State Estimation Over a Shared Communication Medium

We consider state estimation for multiple plants across a shared communication network. Each linear time-invariant plant transmits information through the common network according to either a time-triggered or an event-triggered rule. For an event-triggered algorithm with carrier sense multiple access (CSMA), each plant is assumed to access the network based on a priority mechanism. For a time-triggered algorithm combined with time division multiple access (TDMA), each plant uses the network according to a schedule that is decided a priori . Performance in terms of the communication frequency and the estimation error covariance is analytically characterized for event-triggered schemes. Using these characterizations, we show that event-triggered schemes may perform worse than time-triggered schemes when the effect of the communication network is explicitly considered.

Concepts of the database in contemporary media practice

Abstract Contemporary remix practices in online video have flourished, due to the unprecedented access to our shared media culture that has been made possible by the databases underpinning online space. The technological and functional specificities of the database intercede our experiences in digital culture and influence how we understand our culture that increasingly occupies the database. They also influence how we express ideas about that culture through creative practices. The technological and, correspondingly, cultural significances of the database are articulated in the digitally specific remix video sub-genre, YouTube Poop. YouTube Poop relies on the database for the existing media content that it appropriates. Moreover, it narratively and aesthetically responds to the database by articulating the concepts of technological error, ahistoricism, multi-temporality, media abundance, the constant availability and the achronological, non-hierarchical, unclassified nature of media that the database has introduced to contemporary culture. In this article, the audio-visual narratives of three recent YouTube Poop videos are analysed in order to establish how they articulate the conceptual implications of the database in contemporary digital culture.