300 mm Epitaxy: challenges and opportunities from a wafer manufacturer’s point of view

Results on 300 mm silicon wafer epitaxy according to the 0.18 μm design rule requirements are presented. Wafer uniformity, surface metals, geometry, and thermal stability demonstrate production capabilities. Localized light scattering particles and crystal defects are identified as the largest technological challenge. Preliminary experiments indicate that industry’s requirements can be met. The p/p+ epitaxial wafer is the best candidate to meet the 300 mm cost challenge, as well as the technological requirements for integrated circuit manufacturing.     

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

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

Augmentation and displacement effects of multiplayer social network games: Examining the roles of social interactions and co-players’ identities

The academic debate on whether gameplay has a positive or negative effect on players’ psychosocial well-being has yet to cease. To resolve this debate, this study focuses on multiplayer social network games (MSNGs), the affordances of which may lead to the coexistence of augmentation and displacement effects. To unpack the conditions under which gameplay has a positive or negative relationship with psychological well-being, this study distinguishes between co-player interaction modes (in-game social interactions vs. social media interactions) and between co-players’ identity types (offline friends/acquaintances vs. guild members). An online survey was conducted with 300 gamers in China. The results revealed that more in-game interaction with co-players was positively associated with players’ loneliness, whereas more social media interaction with co-players was negatively related to players’ loneliness, regardless of the co-players’ identities. However, players who played with offline friends/acquaintances did engage in more social interactions than those who played with guild members, especially social media interactions. Moreover, the effect of playing with friends/acquaintances or guild members on players’ loneliness was fully mediated by in-game social interactions and social media interactions. That is, the psychosocial influence of gameplay heavily depends on the exact social interactions that players are involved in rather than on general time spent in games, and the augmentation and displacement effects possibly coincide within one game.     

An architecture of ATM‐based PCS network: Signaling traffic and capacity

In this paper, we propose an ATM‐based Personal Communication Service (PCS) network architecture with ring‐based access networks. We also propose a simple ring management scheme using ATM Add‐Drop‐Multiplexers (ADM). The ring has a Virtual Star topology, and we manage its bandwidth at two levels: Virtual Path (VP) level and Virtual Channel (VC) level. We consider four different types of configurations according to the locations of visitor location register (VLR) and mobile switching center (MSC) functions, and obtain signaling load and processing load. A 150 Mb/s‐dual ring can support about 5,500 homogeneous ON–OFF voice sources. This ring capacity corresponds to covering approximately 180 cells in the case of 30 connections per cell. Even though we are here concerned with evaluating the proposed network for voice traffic, we can extend this study to the analysis of the proposed ATM‐based PCS network accommodating various types of multimedia traffic as a further study. This revised version was published online in August 2006 with corrections to the Cover Date.     

Vehicular ad hoc networks (VANETS): status, results, and?challenges

Recent advances in hardware, software, and communication technologies are enabling the design and implementation of a whole range of different types of networks that are being deployed in various environments. One such network that has received a lot of interest in the last couple of years is the Vehicular Ad-Hoc Network (VANET). VANET has become an active area of research, standardization, and development because it has tremendous potential to improve vehicle and road safety, traffic efficiency, and convenience as well as comfort to both drivers and passengers. Recent research efforts have placed a strong emphasis on novel VANET design architectures and implementations. A?lot of VANET research work have focused on specific areas including routing, broadcasting, Quality of Service (QoS), and security. We survey some of the recent research results in these areas. We present a review of wireless access standards for VANETs, and describe some of the recent VANET trials and deployments in the US, Japan, and the European Union. In addition, we also briefly present some of the simulators currently available to VANET researchers for VANET simulations and we assess their benefits and limitations. Finally, we outline some of the VANET research challenges that still need to be addressed to enable the ubiquitous deployment and widespead adoption of scalable, reliable, robust, and secure VANET architectures, protocols, technologies, and services.     

To shop or not: Understanding Chinese consumers’ live-stream shopping intentions from the perspectives of uses and gratifications,perceived network size,perceptions of digital celebrities,and shopping orientations

Live-stream shopping is experiencing unprecedented growth. However, research in live-stream commerce is in its infancy. The current study integrates uses and gratifications, perceived network size, perceptions of digital celebrities, and experience-focused shopping orientation to clarify motivations for live-stream shopping. Accordingly, the current study used a questionnaire to collect data from 339 Chinese consumers and structural equation modeling to analyze data in AMOS 24. In this study, individuals were motivated by gratifications that were (1) hedonic (perceived enjoyment), (2) utilitarian (self-presentation), and (3) social (social presence and interaction). Moreover, perceived network size significantly predicted perceived enjoyment, social interaction, social presence, and utility. In addition, experience-focused shopping orientation mediated the relationships among perceived enjoyment, self-presentation, social interaction, and live-stream shopping intentions. Finally, the mediating roles of the perceptions of digital celebrities in the relationships of perceived network size with perceived utility, perceived engagement, social interaction, social presence, and self-presentation were confirmed.     

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

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

Editor’s Note: Biomedical Signal and Image Processing Systems

Journal of Signal Processing Systems -     

Synthesis and Characterization of Sol–Gel Screen Printed Gd:ZnO (GZO) Film Towards Opto-Electronic Applications

Semiconductors - In this study, Gd0.02Zn0.98O (GZO) film was coated onto ordinary glass substrate by unusual sol–gel screen printing procedure. Gadolinium was successfully integrated into ZnO...     

Accurate calculation and Matlab based fast realization of merit function’s Hesse matrix for the design of multilayer optical coating

To improve the current status of home multilayer optical coating design with low speed and poor efficiency when a large layer number occurs, the accurate calculation and fast realization of merit function＇s gradient and Hesse matrix is pointed out. Based on the matrix method to calculate the spectral properties of multilayer optical coating, an analytic model is established theoretically. And the corresponding accurate and fast computation is successfully achieved by programming with Matlab. Theoretical and simulated results indicate that this model is mathematically strict and accurate, and its maximal precision can reach floating-point operations in the computer, with short time and fast speed. Thus it is very suitable to improve the optimal search speed and efficiency of local optimization methods based on the derivatives of merit fimction. It has outstanding performance in multilayer optical coating design with a large layer number.     

Editor’s Note: Special Issue on Big Data Analysis and Privacy

Journal of Signal Processing Systems -     

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

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

Digital natives’ snack content consumption and their goals: A means-end chain approach

This study explores digital natives’ consumption of snack contents, which are short-form digital contents that reflects on the emerging trend of snack culture, referring to the participative, multi-tasking, and shortened consumption of digital contents. Specifically, employing goal theory and a means-end chain approach, this study investigates digital natives’ snack content consumption behaviors and the goals they pursue through those behaviors. Data were collected using laddering interviews, a type of semi-structured interview, and the results of the analyses were presented in a hierarchical goal map that identified four attributes and 14 goals associated with snack content consumption. The findings show that information acquisition, sense of accomplishment, fun, and restorative are the main four values users obtain through the usage of snack contents. This empirical study enhances the understanding of digital natives’ goals in consuming snack contents and provides insights into the current trend of digital content consumption.     

Understanding publics’ post-crisis social media engagement behaviors: An examination of antecedents and mediators

This study examines the psychological mechanisms underlying the process that enables publics’ individual differences (e.g., the levels of uncertainty avoidance and social media usage) to give rise to varying post-crisis social media engagement intentions (e.g., information seeking, support seeking, and negative word-of-mouth). The study confirms that this process is serially mediated by perceived threat severity, perceived susceptibility, and negative emotions. These psychological mediators, however, function differently between uncertainty avoidance and social media usage. For uncertainty avoidance, a high arousal negative emotion (e.g., anger, fear) is a more essential step to influence engagement intentions than a low arousal emotion (e.g., shame, guilt). For social media usage, however, the type of aroused negative emotions does not matter. Rather, the relationship social media usage has with information seeking is different from that with support seeking and negative word-of-mouth intentions. Social media usage induces information seeking intentions only through publics’ cognitive appraisals of the situation without the activation of negative emotions, while it induces supporting seeking and negative word-of-mouth intentions through both cognitive appraisals and negative emotion arousals.     

New unbiased adaptive IIR filter: it’s robust and variable step-size versions and application to active noise control

This paper proposes a robust variable step-size adaptive IIR filter realized by a new bias-free structure (BFS). Unlike equation error (EQE) method that uses a desired signal contaminated with observation noise, the BFS employs a filter driven by the output of the plant estimate and this achieves a bias-free estimate of the denominator of the system function. In addition, the adaptation is made robust to the observation noise by the Griffiths’ LMS adaptation, which uses the cross-correlation estimate between the input and the desired signal for its adaptation gradient computation. A robust variable step-size adaptation is also realized by the Griffiths’ gradient. The proposed structure is referred to as BFSGV and has good modeling capability with improved convergence rate and reduced misadjustment. For system identification, the proposed BFSGV algorithm gives a 3 dB improvement in the performance index over EQE method. The proposed BFSGV has been applied to active noise control (ANC). The BSFGV structure is used for secondary path (SP) estimation, and for the main path (MP), BFS structure with step-size varied according to Okello’s method (BSFV) is used. The new ANC system for narrowband noise field is found to be having 4 times faster convergence rate and an additional noise reduction of 15dB over that FIR for MP and the EQE for SP. Further, the use of the proposed ANC IIR algorithm achieves computational savings compared to that of FIR. For the broadband noise field, the proposed method that uses BSFV for MP and BSFGV for SP provides 18 times faster convergence rate and 2.5 dB reduction in ANC error compare to that of the ANC using FIR for MP and the EQE for SP estimation.     

How online ratings and trust influence health consumers’ physician selection intentions: An experimental study

Consumers’ growing reliance on the web information when choosing physicians has drawn attention to the need for more research into online physician ratings. This study conducted an experimental design to explore the roles of trust in different stages and three key online rating characteristics, including overall numerical ratings (high or general), review volume (high or low), and a comparison of the effect rating and attitude rating (higher or lower effect rating than attitude rating), in influencing health consumers’ choices. Results suggested that the overall numerical rating and review volume were significantly and positively correlated with the physician selection intention. Perceived physician trustworthiness completely mediated the effect of the review volume on consumer intentions, while initial trust in online physician ratings produced a moderating effect. The comparison of sub-dimension rating scores induces consumers’ regulatory focus and further moderated the relationship between overall rating score and consumers’ selection intentions, as well as the relationship between perceived physician trustworthiness and consumers’ selection intentions. Implications, limitations and future research directions are also discussed.     

TBFN: Trust Based Friend Network Design by Analyzing User’s Voice Call and SMS Pattern

Due to rapid development of Web 2.0 Technology social networking have gained explosive growth. This paper proposes a comparatively new approach to build a trust based social network named Trust Based Friend Net (TBFN) for smartphone users. In TBFN, call log and sms log extracted from user’s smartphone are outsourced into the corresponding social network cloud. Analyzing those real datasets the cloud service provider determines trust values of different direct and indirect friends of smartphone users. Global analysis of everyone’s data results in forming a trusted global social network that is free from fake profiles and that minimizes unscrupulous activities.