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Organisations such as hospitals and the public are increasingly relying on large computer networks to access information and to communicate multimedia-type data. To assess the effectiveness of these networks, the traffic parameters need to be analysed. Due to the quantity of the data packets, examining each packet's transmission parameters is not practical, especially in real time. Sampling techniques allow a subset of packets that accurately represents the original traffic to be examined and they are thus important in evaluating the performance of multimedia networks. In this study, an adaptive sampling technique based on regression and a fuzzy inference system was developed. The technique dynamically updates the number of packets sampled by responding to the traffic's variations. Its performance was found to be superior to the conventional nonadaptive sampling methods. [ABSTRACT FROM AUTHOR]

Mobile cloud computing (MCC) is becoming a popular mobile technology that aims to augment local resources of mobile devices, such as energy, computing, and storage, by using available cloud services and functionalities. The offloading process is one of the techniques used in MCC to enhance the capabilities of mobile devices by moving mobile data and computation-intensive operations to cloud platforms. Several techniques have been proposed to perform and improve the efficiency and effectiveness of the offloading process, such as multi-criteria decision analysis (MCDA). MCDA is a well-known concept that aims to select the best solution among several alternatives by evaluating multiple conflicting criteria, explicitly in decision making. However, as there are a variety of platforms and technologies in mobile cloud computing, it is still challenging for the offloading process to reach a satisfactory quality of service from the perspective of customers' computational service requests. Thus, in this paper, we conduct a literature review that leads to a better understanding of the usability of the MCDA methods in the offloading operation that is strongly reliant on the mobile environment, network operators, and cloud services. Furthermore, we discuss the challenges and opportunities of these MCDA techniques for offloading research in mobile cloud computing. Finally, we recommend a set of future research directions in MCDA used for the mobile cloud offloading process. [ABSTRACT FROM AUTHOR]

Redesigning a product family entails carefully balancing the trade-offs between commonality and differentiation that are governed by the underlying platform architecture. Numerous metrics for commonality and variety exist to support product family and product platform design; however, rarely are they used in concert to help redesign platforms and families of products effectively. In this paper, we introduce an integrated approach that uses multiple product family metrics to establish an effective platform redesign strategy. Specifically, we present a detailed procedure to integrate the generational variety index, product line commonality index, and design structure matrix to prioritize components for redesign based on variety and commonality needs in a family of products. While all three of these tools exist in the literature and have been used extensively to support product family design, the novelty in our work lies in their integration to establish a redesign strategy for platform architectures that achieves a better balance between the commonality and variety within a product family. To demonstrate the proposed approach, case studies involving two generations of wireless computer mice and two families of dishwashers are presented. Ongoing and future work is also discussed. [ABSTRACT FROM AUTHOR]

Wireless 3-D network-on-chips (NoCs) with inductive-coupling ThruChip interfaces provide a large degree of flexibility for customizing the number of arbitrary chips in a package after chips have been fabricated. To simplify the vertical communication interfaces, static time division multiple access (TDMA) is used for the vertical broadcast buses, while arbitrary or customized topologies can be used for the intrachip network. This paper proposes two techniques to break through the simple static TDMA-based vertical buses while maintaining a simple communication interface. The first technique is headfirst sliding (HS) routing to reduce the waiting time for acquiring the communication time-slot. HS routing selects the best vertical bus based on the current time, taking advantage of static TDMA. The second technique extends carrier sense multiple access with collision detection (CSMA/CD) for vertical broadcast buses. We introduce a packet collision detection technique for inductive-coupling buses and propose two retransmission strategies to reduce the waiting time for packet retransmissions caused by collisions. Network simulation results show that HS routing reduces the communication latency by 39.1% compared with the conventional static TDMA bus-based 3-D NoC that uses the shortest path routing. The proposed CSMA/CD bus also improves the latency by 52.5% and throughput by 34.1%. The full-system simulation results show that HS routing and the proposed CSMA/CD technique reduce the application execution time accordingly while maintaining the average flit transfer energy overhead modest. [ABSTRACT FROM AUTHOR]

In this paper, we propose a hybrid iterated local search (ILS) heuristic, named GPP4G-ILS, to solve the global planning problem of survivable wireless networks. The planning problem of wireless networks is to determine a set of sites among potential sites to install the various network devices in order to cover a given geographical area. It should also make the connections between the devices in accordance with well-defined constraints. The global planning consists in solving this problem without dividing it into several subproblems. The objective is to minimize the cost of the network while maximizing its survivability. The GPP4G-ILS algorithm is a new form of hybridization between the ILS algorithm and the integer linear programing (ILP) method. We propose a configuration that allows to reuse a previously developed ILP algorithm by integrating it in the ILS algorithm. This allows to benefit from the advantages of both methods. The ILS algorithm is used to effectively explore the search space, while the ILP algorithm is used to intensify the solutions obtained. The performance of the algorithm was evaluated using an exact method that generates optimal solutions for small instances. For larger instances, lower bounds have been calculated using a relaxation of the problem. The results show that the proposed algorithm is able to reach solutions that are, on average, within 0.06% of the optimal solutions and 2.43% from the lower bounds for the instances that cannot be solved optimally, within a reduced computation time. [ABSTRACT FROM AUTHOR]

Computation offloading is an effective way to alleviate the resource limited problem of mobile devices. However, the offloading is not an always advantageous strategy for under some circumstances the overhead in time and energy may turn out to be greater than the offloading savings. Therefore, an offloading decision scheme is in demand for mobile devices to decide whether to offload a computation task to the server or to execute it in a local processor. In this paper, the offloading decision problem is translated into a dynamic execution mode selection problem, the objective of which is to minimize the task execution delay and reduce the energy consumption of mobile devices. A novel execution mode adjustment mechanism is introduced to make the execution process more flexible for real-time environment variation. Numerical results indicate that the proposed scheme can significantly reduce the task execution delay in an energy-efficient way. [ABSTRACT FROM AUTHOR]

The article presents research which examined the effects of the human finger's type, length, and width and of Chinese characters' first stroke direction, number of strokes, and structure on Chinese handwriting performance on mobile touch devices. The study found that the six factors related to finger input and the Chinese characters significantly affected handwriting performance, particularly in terms of input time and accuracy.

Abstract: To overcome the overhead involved with channel estimation, several non-coherent distributed space–time coding (DSTC) strategies for two-way wireless relay networks (TWRNs) using the amplify-and-forward and the decode-and-forward protocol have been recently proposed that do not require channel state information (CSI) at any node to decode the information symbols. In this paper, novel differential DSTC strategies for TWRNs using the two- and three-phase protocol are proposed. In our transmission schemes, the relays do not waste power to transmit information known at the respective destination nodes. This is achieved by combining the symbols from both terminals received at the relays into a single symbol of the unaltered constellation. Furthermore, in our strategies, the direct link between the communicating terminals can be naturally incorporated to further improve the diversity gain. Simulations show a substantially improved performance in terms of bit error rate (BER) of the proposed strategies as compared to the existing strategies. [Copyright &y& Elsevier]

Bluetooth Low Energy (BLE) is a recently developed energy-efficient short-range wireless communication protocol. In this paper, we discuss and compare the maximum peer-to-peer throughput, the minimum frame turnaround time, and the energy consumption for three protocols, namely BLE, IEEE 802.15.4 and SimpliciTI. The specifics and the main contributions are the results both of the theoretical analysis and of the empirical measurements, which were executed using the commercially available hardware transceivers and software stacks. The presented results reveal the protocols' capabilities and enable one to estimate the feasibility of using these technologies for particular applications. Based on the presented results, we draw conclusions regarding the feasibility and the most suitable application scenarios of the BLE technology. [ABSTRACT FROM AUTHOR]

Massive levels of integration are making modern multicore chips all pervasive in several domains. High performance, robustness, and energy-efficiency are crucial for the widespread adoption of such platforms. Networks-on-Chip (NoCs) have emerged as communication backbones to enable a high degree of integration in multicore Systems-on-Chip (SoCs). Despite their advantages, an important performance limitation in traditional NoCs arises from planar metal interconnect-based multihop links with high latency and power consumption. This limitation can be addressed by drawing inspiration from the evolution of natural complex networks, which offer great performance-cost trade-offs. Analogous with many natural complex systems, future multicore chips are expected to be hierarchical and heterogeneous in nature as well. In this article we undertake a detailed performance evaluation for hierarchical small-world NoC architectures where the long-range communications links are established through the millimeter-wave wireless communication channels. Through architecture-space exploration in conjunction with novel power-efficient on-chip wireless link design, we demonstrate that it is possible to improve performance of conventional NoC architectures significantly without incurring high area overhead. [ABSTRACT FROM AUTHOR]

Trust is an essential component of every interaction we make. For some transactions we need very little trust, while for others we may be quite risk averse. In this paper we investigate trust in an Internet-of-Things environment. Can we trust devices? How can we quantify trust in devices? [ABSTRACT FROM AUTHOR]

Copyright of Latin-American Journal of Physics Education is the property of Latin-American Physics Education Network 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.)

We provide inner bound and outer bound for the total number of degrees of freedom of the K user multiple-input multiple-output (MIMO) Gaussian interference channel with M antennas at each transmitter and N antennas at each receiver if the channel coefficients are time-varying and drawn from a continuous distribution. The bounds are tight when the ratio \max(M,N) \over \min(M,N)=R is equal to an integer. For this case, we show that the total number of degrees of freedom is equal to \min(M,N)K if K \leq R and \min(M,N)R \over R+1K if K > R. Achievability is based on interference alignment. We also provide examples where using interference alignment combined with zero forcing can achieve more degrees of freedom than merely zero forcing for some MIMO interference channels with constant channel coefficients. [ABSTRACT FROM PUBLISHER]

Phase-shift cyclic-delay diversity (PS CDD) scheme and space-frequency-block-code (SFBC) PS CDD are developed for multipleinput- multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) systems. The proposed PS CDD scheme preserves the diversity advantage of traditional CDD in uncorrelated multiantenna channels, and furthermore removes frequencyselective nulling problem of the traditional CDD in correlated multiantenna channels. [ABSTRACT FROM AUTHOR]

Copyright of International Journal of InformaticsTechnologies is the property of Institute of Informatics, Gazi University 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 diffusion of municipal wireless initiatives in the United States has led to questions about why municipalities undertake these costly and sometimes politically risky policies. This study is a first attempt at understanding why wireless initiatives diffuse between municipalities. An examination of cities in the Northeastern U.S. suggests that population size and competition are the only significant factors in the decision to adopt these initiatives, though reduced regression models suggest the influence of other factors. [ABSTRACT FROM AUTHOR]

Bluetooth is a wireless device, composed of hardware and software with interoperability requirements. Bluetooth specifies short range of communication between mobile's and computer devices. by using cryptographic technique the transfer of date should me made secure. [ABSTRACT FROM AUTHOR]

Unit selection speech systems generate synthetic speech by concatenation of acoustic units that are chosen by means of a Viterbi search on a previously recorded corpus of the same speaker. Given the finite nature of the corpus, there is usually a trade-off between the acoustic quality of the signal, and the quality of the prosody. Proposed is a parallel Viterbi search considering multiple intonation contours that improves at the same time both acoustic quality and intonation, while maintaining the computational efficiency of the process. [ABSTRACT FROM AUTHOR]

Abstract: An IEEE 802.11 wireless device can leave traces of its presence in the volatile memories of nearby wireless devices. While the devices need to be in radio range of each other for this to happen, they do not need to be connected to the same network—or to any network at all. Traces appear in the form of full wire-type frames; a residue of the signals in the ether. We examine types of information that can be extracted from such residual frames and explore the conditions under which traces develop and persist. Their availability is determined by factors in both in the external environment (the types of signals in the ether) and the internal environment (the configuration and particulars of a device's wifi stack). To isolate some of these factors, we have created memory dumps of devices in various environments and configurations. Analysis of the dumps has offered insights into the conditions determining creation and decay of the traces. The results indicate that they will be available in a limited number of real-world scenarios. We conclude with practical advice on triaging and preservation. [Copyright &y& Elsevier]

The article offers information on the HOBO ZW Series from Onset Computer Corp., which is composed of wireless data nodes that monitor the energy use and environmental conditions in buildings through a central personal computer (PC).