Seamless Mobile Multimedia Broadcasting Using Adaptive Error Recovery

Directory of Open Access Journals (Sweden)

Carlos M. Lentisco

2017-01-01

Full Text Available Multimedia services over mobile networks present several challenges, such as ensuring a reliable delivery of multimedia content, avoiding undesired service disruptions, or reducing service latency. HTTP adaptive streaming addresses these problems for multimedia unicast services, but it is not efficient from the point of view of radio resource consumption. In Long-Term Evolution (LTE networks, multimedia broadcast services are provided over a common radio channel using a combination of forward error correction and unicast error recovery techniques at the application level. This paper discusses how to avoid service disruptions and reduce service latency for LTE multimedia broadcast services by adding dynamic adaptation capabilities to the unicast error recovery process. The proposed solution provides a seamless mobile multimedia broadcasting without compromising the quality of the service perceived by the users.

On the Feasibility of Wireless Multimedia Sensor Networks over IEEE 802.15.5 Mesh Topologies.

Science.gov (United States)

Garcia-Sanchez, Antonio-Javier; Losilla, Fernando; Rodenas-Herraiz, David; Cruz-Martinez, Felipe; Garcia-Sanchez, Felipe

2016-05-05

Wireless Multimedia Sensor Networks (WMSNs) are a special type of Wireless Sensor Network (WSN) where large amounts of multimedia data are transmitted over networks composed of low power devices. Hierarchical routing protocols typically used in WSNs for multi-path communication tend to overload nodes located within radio communication range of the data collection unit or data sink. The battery life of these nodes is therefore reduced considerably, requiring frequent battery replacement work to extend the operational life of the WSN system. In a wireless sensor network with mesh topology, any node may act as a forwarder node, thereby enabling multiple routing paths toward any other node or collection unit. In addition, mesh topologies have proven advantages, such as data transmission reliability, network robustness against node failures, and potential reduction in energy consumption. This work studies the feasibility of implementing WMSNs in mesh topologies and their limitations by means of exhaustive computer simulation experiments. To this end, a module developed for the Synchronous Energy Saving (SES) mode of the IEEE 802.15.5 mesh standard has been integrated with multimedia tools to thoroughly test video sequences encoded using H.264 in mesh networks.

On the Feasibility of Wireless Multimedia Sensor Networks over IEEE 802.15.5 Mesh Topologies

Directory of Open Access Journals (Sweden)

Antonio-Javier Garcia-Sanchez

2016-05-01

Full Text Available Wireless Multimedia Sensor Networks (WMSNs are a special type of Wireless Sensor Network (WSN where large amounts of multimedia data are transmitted over networks composed of low power devices. Hierarchical routing protocols typically used in WSNs for multi-path communication tend to overload nodes located within radio communication range of the data collection unit or data sink. The battery life of these nodes is therefore reduced considerably, requiring frequent battery replacement work to extend the operational life of the WSN system. In a wireless sensor network with mesh topology, any node may act as a forwarder node, thereby enabling multiple routing paths toward any other node or collection unit. In addition, mesh topologies have proven advantages, such as data transmission reliability, network robustness against node failures, and potential reduction in energy consumption. This work studies the feasibility of implementing WMSNs in mesh topologies and their limitations by means of exhaustive computer simulation experiments. To this end, a module developed for the Synchronous Energy Saving (SES mode of the IEEE 802.15.5 mesh standard has been integrated with multimedia tools to thoroughly test video sequences encoded using H.264 in mesh networks.

MB-OFDM-UWB Based Wireless Multimedia Sensor Networks for Underground Coalmine: A Survey

Science.gov (United States)

Han, Ruisong; Yang, Wei; You, Kaiming

2016-01-01

Safety production of coalmines is a task of top priority which plays an important role in guaranteeing, supporting and promoting the continuous development of the coal industry. Since traditional wireless sensor networks (WSNs) cannot fully meet the requirements of comprehensive environment monitoring of underground coalmines, wireless multimedia sensor networks (WMSNs), enabling the retrieval of multimedia information, are introduced to realize fine-grained and precise environment surveillance. In this paper, a framework for designing underground coalmine WMSNs based on Multi-Band Orthogonal Frequency-Division Multiplexing Ultra-wide Band (MB-OFDM-UWB) is presented. The selection of MB-OFDM-UWB wireless transmission solution is based on the characteristics of underground coalmines. Network structure and design challenges are analyzed first, which is the foundation for further discussion. Then, key supporting technologies and open research areas in different layers are surveyed, and we provide a detailed literature review of the state of the art strategies, algorithms and general solutions in these issues. Finally, other research issues like localization, information processing, and network management are discussed. PMID:27999258

MB-OFDM-UWB Based Wireless Multimedia Sensor Networks for Underground Coalmine: A Survey.

Science.gov (United States)

Han, Ruisong; Yang, Wei; You, Kaiming

2016-12-16

Safety production of coalmines is a task of top priority which plays an important role in guaranteeing, supporting and promoting the continuous development of the coal industry. Since traditional wireless sensor networks (WSNs) cannot fully meet the requirements of comprehensive environment monitoring of underground coalmines, wireless multimedia sensor networks (WMSNs), enabling the retrieval of multimedia information, are introduced to realize fine-grained and precise environment surveillance. In this paper, a framework for designing underground coalmine WMSNs based on Multi-Band Orthogonal Frequency-Division Multiplexing Ultra-wide Band (MB-OFDM-UWB) is presented. The selection of MB-OFDM-UWB wireless transmission solution is based on the characteristics of underground coalmines. Network structure and design challenges are analyzed first, which is the foundation for further discussion. Then, key supporting technologies and open research areas in different layers are surveyed, and we provide a detailed literature review of the state of the art strategies, algorithms and general solutions in these issues. Finally, other research issues like localization, information processing, and network management are discussed.

Semantic HyperMultimedia Adaptation Schemes and Applications

CERN Document Server

Bieliková, Mária; Mylonas, Phivos; Tsapatsoulis, Nicolas

2013-01-01

Nowadays, more and more users are witnessing the impact of Hypermedia/Multimedia as well as the penetration of social applications in their life. Parallel to the evolution of the Internet and Web, several Hypermedia/Multimedia schemes and technologies bring semantic-based intelligent, personalized and adaptive services to the end users. More and more techniques are applied in media systems in order to be user/group-centric, adapting to different content and context features of a single or a community user. In respect to all the above, researchers need to explore and study the plethora of challenges that emergent personalisation and adaptation technologies bring to the new era. This edited volume aims to increase the awareness of researchers in this area. All contributions provide an in-depth investigation on research and deployment issues, regarding already introduced schemes and applications in Semantic Hyper/Multimedia and Social Media Adaptation. Moreover, the authors provide survey-based articles, so as p...

Energy and Delay Optimization of Heterogeneous Multicore Wireless Multimedia Sensor Nodes by Adaptive Genetic-Simulated Annealing Algorithm

Directory of Open Access Journals (Sweden)

Xing Liu

2018-01-01

Full Text Available Energy efficiency and delay optimization are significant for the proliferation of wireless multimedia sensor network (WMSN. In this article, an energy-efficient, delay-efficient, hardware and software cooptimization platform is researched to minimize the energy cost while guaranteeing the deadline of the real-time WMSN tasks. First, a multicore reconfigurable WMSN hardware platform is designed and implemented. This platform uses both the heterogeneous multicore architecture and the dynamic voltage and frequency scaling (DVFS technique. By this means, the nodes can adjust the hardware characteristics dynamically in terms of the software run-time contexts. Consequently, the software can be executed more efficiently with less energy cost and shorter execution time. Then, based on this hardware platform, an energy and delay multiobjective optimization algorithm and a DVFS adaption algorithm are investigated. These algorithms aim to search out the global energy optimization solution within the acceptable calculation time and strip the time redundancy in the task executing process. Thus, the energy efficiency of the WMSN node can be improved significantly even under strict constraint of the execution time. Simulation and real-world experiments proved that the proposed approaches can decrease the energy cost by more than 29% compared to the traditional single-core WMSN node. Moreover, the node can react quickly to the time-sensitive events.

Multimedia Adaptation in Ubiquitous Environments: Benefits of Structured Multimedia Documents

NARCIS (Netherlands)

P.S. Cesar Garcia (Pablo Santiago); I. Vaishnavi (Ishan); R. Kernchen; S. Meissner; M. Boussard; A. Spedalieri; B. Gao (Bo); D.C.A. Bulterman (Dick)

2008-01-01

htmlabstractThis paper demonstrates the advantages of using structured multimedia documents for session management and media distribution in ubiquitous environments. We show how document manipulations can be used to perform powerful operations such as content to context adaptation and presentation

Multi-agent Negotiation Mechanisms for Statistical Target Classification in Wireless Multimedia Sensor Networks

Science.gov (United States)

Wang, Xue; Bi, Dao-wei; Ding, Liang; Wang, Sheng

2007-01-01

The recent availability of low cost and miniaturized hardware has allowed wireless sensor networks (WSNs) to retrieve audio and video data in real world applications, which has fostered the development of wireless multimedia sensor networks (WMSNs). Resource constraints and challenging multimedia data volume make development of efficient algorithms to perform in-network processing of multimedia contents imperative. This paper proposes solving problems in the domain of WMSNs from the perspective of multi-agent systems. The multi-agent framework enables flexible network configuration and efficient collaborative in-network processing. The focus is placed on target classification in WMSNs where audio information is retrieved by microphones. To deal with the uncertainties related to audio information retrieval, the statistical approaches of power spectral density estimates, principal component analysis and Gaussian process classification are employed. A multi-agent negotiation mechanism is specially developed to efficiently utilize limited resources and simultaneously enhance classification accuracy and reliability. The negotiation is composed of two phases, where an auction based approach is first exploited to allocate the classification task among the agents and then individual agent decisions are combined by the committee decision mechanism. Simulation experiments with real world data are conducted and the results show that the proposed statistical approaches and negotiation mechanism not only reduce memory and computation requirements in WMSNs but also significantly enhance classification accuracy and reliability. PMID:28903223

Adaptive Wireless Multimedia Services

OpenAIRE

Yi, Xiaokun

2006-01-01

Context-awareness is a hot topic in mobile computing currently. A lot of importance is being attached to facilitating the user of various mobile computing devices to provide services that are more “user-centric”. One aspect of context-awareness is to perceive variations in available resources, and to make decisions based on the feedback to enable applications to automatically adapt to the current environment. For Voice over IP (VoIP) software phones (softphones), variations in network perform...

Integer-linear-programing optimization in scalable video multicast with adaptive modulation and coding in wireless networks.

Science.gov (United States)

Lee, Dongyul; Lee, Chaewoo

2014-01-01

The advancement in wideband wireless network supports real time services such as IPTV and live video streaming. However, because of the sharing nature of the wireless medium, efficient resource allocation has been studied to achieve a high level of acceptability and proliferation of wireless multimedia. Scalable video coding (SVC) with adaptive modulation and coding (AMC) provides an excellent solution for wireless video streaming. By assigning different modulation and coding schemes (MCSs) to video layers, SVC can provide good video quality to users in good channel conditions and also basic video quality to users in bad channel conditions. For optimal resource allocation, a key issue in applying SVC in the wireless multicast service is how to assign MCSs and the time resources to each SVC layer in the heterogeneous channel condition. We formulate this problem with integer linear programming (ILP) and provide numerical results to show the performance under 802.16 m environment. The result shows that our methodology enhances the overall system throughput compared to an existing algorithm.

Integer-Linear-Programing Optimization in Scalable Video Multicast with Adaptive Modulation and Coding in Wireless Networks

Directory of Open Access Journals (Sweden)

Dongyul Lee

2014-01-01

Full Text Available The advancement in wideband wireless network supports real time services such as IPTV and live video streaming. However, because of the sharing nature of the wireless medium, efficient resource allocation has been studied to achieve a high level of acceptability and proliferation of wireless multimedia. Scalable video coding (SVC with adaptive modulation and coding (AMC provides an excellent solution for wireless video streaming. By assigning different modulation and coding schemes (MCSs to video layers, SVC can provide good video quality to users in good channel conditions and also basic video quality to users in bad channel conditions. For optimal resource allocation, a key issue in applying SVC in the wireless multicast service is how to assign MCSs and the time resources to each SVC layer in the heterogeneous channel condition. We formulate this problem with integer linear programming (ILP and provide numerical results to show the performance under 802.16 m environment. The result shows that our methodology enhances the overall system throughput compared to an existing algorithm.

Routing in Wireless Multimedia Home Networks

NARCIS (Netherlands)

Scholten, Johan; Jansen, P.G.; Hop, Laurens

This paper describes an adapted version of the destination sequenced distance vector routing protocol (DSDV) which is suitable to calculate routes in a wireless real-time home network. The home network is based on a IEEE 802.11b ad hoc network and uses a scheduled token to enforce real-time

Routing in Wireless Multimedia Home Networks

NARCIS (Netherlands)

Scholten, Johan; Jansen, P.G.; Hop, Laurens

This paper describes an adapted version of the destination sequenced distance vector routing protocol (DSDV) which is suitable to calculate routes in a wireless ¿real-time¿ home network. The home network is based on a IEEE 802.11b ad hoc network and uses a scheduled token to enforce real-time

An Adaptive QoS Routing Solution for MANET Based Multimedia Communications in Emergency Cases

Science.gov (United States)

Ramrekha, Tipu Arvind; Politis, Christos

The Mobile Ad hoc Networks (MANET) is a wireless network deprived of any fixed central authoritative routing entity. It relies entirely on collaborating nodes forwarding packets from source to destination. This paper describes the design, implementation and performance evaluation of CHAMELEON, an adaptive Quality of Service (QoS) routing solution, with improved delay and jitter performances, enabling multimedia communication for MANETs in extreme emergency situations such as forest fire and terrorist attacks as defined in the PEACE project. CHAMELEON is designed to adapt its routing behaviour according to the size of a MANET. The reactive Ad Hoc on-Demand Distance Vector Routing (AODV) and proactive Optimized Link State Routing (OLSR) protocols are deemed appropriate for CHAMELEON through their performance evaluation in terms of delay and jitter for different MANET sizes in a building fire emergency scenario. CHAMELEON is then implemented in NS-2 and evaluated similarly. The paper concludes with a summary of findings so far and intended future work.

QoS Support Polling Scheme for Multimedia Traffic in Wireless LAN MAC Protocol

Institute of Scientific and Technical Information of China (English)

YANG Zhijun; ZHAO Dongfeng

2008-01-01

Quality of service (QoS) support is a key attribute for multimedia traffic including video, voice, and data in wireless local area networks (LANs) but is limited in 802.11-based wireless LANs. A polling-based scheme called the point coordination function (PCF) was developed for 802.11 LANs to support the trans-mission of multimedia traffic. However, the PCF is not able to meet the desired practical traffic differentiation requirements for real-time data. This paper describes a QoS support polling scheme based on the IEEE 802.11 medium access control (MAC) protocol. The scheme uses a two-level polling mechanism with the QoS classes differentiated by two different access policies. Stations with higher priority traffic such as key or real-time data form the first level and can access the common channel through an exhaustive access policy. Other stations with lower priority traffic form the second level and can access the channel through a gated access policy. A system model based on imbedded Markov chain theory and a generation function were setup to explicitly analyze the mean information packet waiting time of the two-level polling scheme. Theo-retical and simulation results show that the new scheme efficiently differentiates services to guarantee better QoS and system stability.

Supporting Adaptation of Wireless Communication Protocols

International Nuclear Information System (INIS)

Dhomeja, L.D.; Soomro, I.A.; Malkani, Y.A.

2016-01-01

Pervasive devices such as mobile phones and PDAs (Personal Digital Assistants) come with different wireless communication capabilities, for example, WiFi (Wireless Fidelity), Bluetooth, IrDA (Infrared), etc. In order for pervasive devices to interact with each other, they need to have matching (alike) communication capabilities, otherwise such heterogeneous devices would not be able to interact with each other. In this paper we address this issue and propose a system that makes devices with heterogeneous wireless communication capabilities communicate with each other. The proposed system supports adaptation of wireless communication protocols through a proxy, which sits between a client and a server, and supports adaptation of wireless communication protocols. Its functionality involves intercepting a request made by a client with a different wireless communication capability (e.g. Bluetooth) from what the server has (e.g. WiFi), connecting to the server and then sending results back to the client. We have tested the system by implementing a messaging service application and running it on the system. The proxy supports all Bluetooth protocols, i.e. OBEX (Object Exchange), L2CAP (Logical Link Control and Adaptation Protocol), RFCOM (Radio Frequency Communication) and WiFi protocol and can run on (J2MW (Java 2 Micro Edition) enabled mobile phones which support both Bluetooth and WiFi capabilities. (author)

Multimedia information processing in the SWAN mobile networked computing system

Science.gov (United States)

Agrawal, Prathima; Hyden, Eoin; Krzyzanowsji, Paul; Srivastava, Mani B.; Trotter, John

1996-03-01

Anytime anywhere wireless access to databases, such as medical and inventory records, can simplify workflow management in a business, and reduce or even eliminate the cost of moving paper documents. Moreover, continual progress in wireless access technology promises to provide per-user bandwidths of the order of a few Mbps, at least in indoor environments. When combined with the emerging high-speed integrated service wired networks, it enables ubiquitous and tetherless access to and processing of multimedia information by mobile users. To leverage on this synergy an indoor wireless network based on room-sized cells and multimedia mobile end-points is being developed at AT&T Bell Laboratories. This research network, called SWAN (Seamless Wireless ATM Networking), allows users carrying multimedia end-points such as PDAs, laptops, and portable multimedia terminals, to seamlessly roam while accessing multimedia data streams from the wired backbone network. A distinguishing feature of the SWAN network is its use of end-to-end ATM connectivity as opposed to the connectionless mobile-IP connectivity used by present day wireless data LANs. This choice allows the wireless resource in a cell to be intelligently allocated amongst various ATM virtual circuits according to their quality of service requirements. But an efficient implementation of ATM in a wireless environment requires a proper mobile network architecture. In particular, the wireless link and medium-access layers need to be cognizant of the ATM traffic, while the ATM layers need to be cognizant of the mobility enabled by the wireless layers. This paper presents an overview of SWAN's network architecture, briefly discusses the issues in making ATM mobile and wireless, and describes initial multimedia applications for SWAN.

Educational Multimedia Profiling Recommendations for Device-Aware Adaptive Mobile Learning

Science.gov (United States)

Moldovan, Arghir-Nicolae; Ghergulescu, Ioana; Muntean, Cristina Hava

2014-01-01

Mobile learning is seeing a fast adoption with the increasing availability and affordability of mobile devices such as smartphones and tablets. As the creation and consumption of educational multimedia content on mobile devices is also increasing fast, educators and mobile learning providers are faced with the challenge to adapt multimedia type…

Proposal of Wireless Traffic Control Schemes for Wireless LANs

Science.gov (United States)

Hiraguri, Takefumi; Ichikawa, Takeo; Iizuka, Masataka; Kubota, Shuji

This paper proposes two traffic control schemes to support the communication quality of multimedia streaming services such as VoIP and audio/video over IEEE 802.11 wireless LAN systems. The main features of the proposed scheme are bandwidth control for each flow of the multimedia streaming service and load balancing between access points (APs) of the wireless LAN by using information of data link, network and transport layers. The proposed schemes are implemented on a Linux machine which is called the wireless traffic controller (WTC). The WTC connects a high capacity backbone network and an access network to which the APs are attached. We evaluated the performance of the proposed WTC and confirmed that the communication quality of the multimedia streaming would be greatly improved by using this technique.

The Wireless ATM Architecture

Directory of Open Access Journals (Sweden)

R. Palitefka

1998-06-01

Full Text Available An overview of the proposed wireless ATM structure is provided. Wireless communication have been developed to a level where offered services can now be extended beyond voice and data. There are already wireless LANs, cordless systems offering data services and mobile data. Wireless LAN systems are basically planned for local, on-promises and in-house networking providing short distance radio or infrared links between computer system. The main challenge of wireless ATM is to harmonise the development of broadband wireless system with service B -ISDN/ATM and ATM LANs, and offer multimedia multiservice features for the support of time-sensitive voice communication, video, desktop multimedia applications, and LAN data traffic for the wireless user.

A Spectrum Sensing Method Based on Signal Feature and Clustering Algorithm in Cognitive Wireless Multimedia Sensor Networks

Directory of Open Access Journals (Sweden)

Yongwei Zhang

2017-01-01

Full Text Available In order to solve the problem of difficulty in determining the threshold in spectrum sensing technologies based on the random matrix theory, a spectrum sensing method based on clustering algorithm and signal feature is proposed for Cognitive Wireless Multimedia Sensor Networks. Firstly, the wireless communication signal features are obtained according to the sampling signal covariance matrix. Then, the clustering algorithm is used to classify and test the signal features. Different signal features and clustering algorithms are compared in this paper. The experimental results show that the proposed method has better sensing performance.

Multimedia content classification metrics for content adaptation

OpenAIRE

Fernandes, Rui; Andrade, M.T.

2015-01-01

Multimedia content consumption is very popular nowadays. However, not every content can be consumed in its original format: the combination of content, transport and access networks, consumption device and usage environment characteristics may all pose restrictions to that purpose. One way to provide the best possible quality to the user is to adapt the content according to these restrictions as well as user preferences. This adaptation stage can be best executed if knowledge about the conten...

Multimedia content classification metrics for content adaptation

OpenAIRE

Fernandes, Rui; Andrade, M.T.

2016-01-01

Multimedia content consumption is very popular nowadays. However, not every content can be consumed in its original format: the combination of content, transport and access networks, consumption device and usage environment characteristics may all pose restrictions to that purpose. One way to provide the best possible quality to the user is to adapt the content according to these restrictions as well as user preferences. This adaptation stage can be best executed if knowledge about the conten...

Adaptive Wireless Transceiver, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Wireless technologies are an increasingly attractive means for spatial data, input, manipulation, and distribution. Mobitrum is proposing an innovative Adaptive...

Adaptive Wavelet Coding Applied in a Wireless Control System.

Science.gov (United States)

Gama, Felipe O S; Silveira, Luiz F Q; Salazar, Andrés O

2017-12-13

Wireless control systems can sense, control and act on the information exchanged between the wireless sensor nodes in a control loop. However, the exchanged information becomes susceptible to the degenerative effects produced by the multipath propagation. In order to minimize the destructive effects characteristic of wireless channels, several techniques have been investigated recently. Among them, wavelet coding is a good alternative for wireless communications for its robustness to the effects of multipath and its low computational complexity. This work proposes an adaptive wavelet coding whose parameters of code rate and signal constellation can vary according to the fading level and evaluates the use of this transmission system in a control loop implemented by wireless sensor nodes. The performance of the adaptive system was evaluated in terms of bit error rate (BER) versus E b / N 0 and spectral efficiency, considering a time-varying channel with flat Rayleigh fading, and in terms of processing overhead on a control system with wireless communication. The results obtained through computational simulations and experimental tests show performance gains obtained by insertion of the adaptive wavelet coding in a control loop with nodes interconnected by wireless link. These results enable the use of this technique in a wireless link control loop.

Adaptive Wavelet Coding Applied in a Wireless Control System

Directory of Open Access Journals (Sweden)

Felipe O. S. Gama

2017-12-01

Full Text Available Wireless control systems can sense, control and act on the information exchanged between the wireless sensor nodes in a control loop. However, the exchanged information becomes susceptible to the degenerative effects produced by the multipath propagation. In order to minimize the destructive effects characteristic of wireless channels, several techniques have been investigated recently. Among them, wavelet coding is a good alternative for wireless communications for its robustness to the effects of multipath and its low computational complexity. This work proposes an adaptive wavelet coding whose parameters of code rate and signal constellation can vary according to the fading level and evaluates the use of this transmission system in a control loop implemented by wireless sensor nodes. The performance of the adaptive system was evaluated in terms of bit error rate (BER versus E b / N 0 and spectral efficiency, considering a time-varying channel with flat Rayleigh fading, and in terms of processing overhead on a control system with wireless communication. The results obtained through computational simulations and experimental tests show performance gains obtained by insertion of the adaptive wavelet coding in a control loop with nodes interconnected by wireless link. These results enable the use of this technique in a wireless link control loop.

A Mobility-aware Broadcasting Infrastructure for a Wireless Internet with Hotspots

NARCIS (Netherlands)

Hesselman, C.E.W.; Eertink, Henk; Eertink, E.H.; Widya, I.A.; Huizer, E.; Kermani, P.

In this paper, we consider the problem of adaptively delivering live multimedia broadcasts (e.g., for applications such as TV, radio, or e-cinema) to a potentially large number of mobile hosts that roam about in a wireless internet with hotspots. We take a user-oriented approach based on an

Radio propagation and adaptive antennas for wireless communication networks

CERN Document Server

Blaunstein, Nathan

2014-01-01

Explores novel wireless networks beyond 3G, and advanced 4G technologies, such as MIMO, via propagation phenomena and the fundamentals of adapted antenna usage.Explains how adaptive antennas can improve GoS and QoS for any wireless channel, with specific examples and applications in land, aircraft and satellite communications.Introduces new stochastic approach based on several multi-parametric models describing various terrestrial scenarios, which have been experimentally verified in different environmental conditionsNew chapters on fundamentals of wireless networks, cellular and non-cellular,

Providing end-to-end QoS for multimedia applications in 3G wireless networks

Science.gov (United States)

Guo, Katherine; Rangarajan, Samapth; Siddiqui, M. A.; Paul, Sanjoy

2003-11-01

As the usage of wireless packet data services increases, wireless carriers today are faced with the challenge of offering multimedia applications with QoS requirements within current 3G data networks. End-to-end QoS requires support at the application, network, link and medium access control (MAC) layers. We discuss existing CDMA2000 network architecture and show its shortcomings that prevent supporting multiple classes of traffic at the Radio Access Network (RAN). We then propose changes in RAN within the standards framework that enable support for multiple traffic classes. In addition, we discuss how Session Initiation Protocol (SIP) can be augmented with QoS signaling for supporting end-to-end QoS. We also review state of the art scheduling algorithms at the base station and provide possible extensions to these algorithms to support different classes of traffic as well as different classes of users.

Adaptive Protocols for Mobile Wireless Networks

National Research Council Canada - National Science Library

Pursley, Michael B

2005-01-01

.... Research results are presented on adaptive, energy-efficient, distributed protocols for mobile wireless networks that must operate effectively over unreliable communication links in highly dynamic...

Design of a Mobile Brain Computer Interface-Based Smart Multimedia Controller

Science.gov (United States)

Tseng, Kevin C.; Lin, Bor-Shing; Wong, Alice May-Kuen; Lin, Bor-Shyh

2015-01-01

Music is a way of expressing our feelings and emotions. Suitable music can positively affect people. However, current multimedia control methods, such as manual selection or automatic random mechanisms, which are now applied broadly in MP3 and CD players, cannot adaptively select suitable music according to the user’s physiological state. In this study, a brain computer interface-based smart multimedia controller was proposed to select music in different situations according to the user’s physiological state. Here, a commercial mobile tablet was used as the multimedia platform, and a wireless multi-channel electroencephalograph (EEG) acquisition module was designed for real-time EEG monitoring. A smart multimedia control program built in the multimedia platform was developed to analyze the user’s EEG feature and select music according his/her state. The relationship between the user’s state and music sorted by listener’s preference was also examined in this study. The experimental results show that real-time music biofeedback according a user’s EEG feature may positively improve the user’s attention state. PMID:25756862

Design of a Mobile Brain Computer Interface-Based Smart Multimedia Controller

Directory of Open Access Journals (Sweden)

Kevin C. Tseng

2015-03-01

Full Text Available Music is a way of expressing our feelings and emotions. Suitable music can positively affect people. However, current multimedia control methods, such as manual selection or automatic random mechanisms, which are now applied broadly in MP3 and CD players, cannot adaptively select suitable music according to the user’s physiological state. In this study, a brain computer interface-based smart multimedia controller was proposed to select music in different situations according to the user’s physiological state. Here, a commercial mobile tablet was used as the multimedia platform, and a wireless multi-channel electroencephalograph (EEG acquisition module was designed for real-time EEG monitoring. A smart multimedia control program built in the multimedia platform was developed to analyze the user’s EEG feature and select music according his/her state. The relationship between the user’s state and music sorted by listener’s preference was also examined in this study. The experimental results show that real-time music biofeedback according a user’s EEG feature may positively improve the user’s attention state.

QoE Power-Efficient Multimedia Delivery Method for LTE-A

OpenAIRE

Mushtaq, M. Sajid; Mellouk, Abdelhamid; Augustin, Brice; Fowler, Scott

2016-01-01

The fastest growing of multimedia services overfuture wireless communication system demand more networkresources, efficient delivery of multimedia service with highusers satisfaction, and power optimization of User Equipments(UEs). The resources and power optimization are significant infuture mobile computing systems, because emerging multimediaservices consume more resources and power. The 4G standard ofLTE-A wireless system has adopted the Discontinuous Reception(DRX) method to extend and o...

Semantic Network Adaptation Based on QoS Pattern Recognition for Multimedia Streams

Science.gov (United States)

Exposito, Ernesto; Gineste, Mathieu; Lamolle, Myriam; Gomez, Jorge

This article proposes an ontology based pattern recognition methodology to compute and represent common QoS properties of the Application Data Units (ADU) of multimedia streams. The use of this ontology by mechanisms located at different layers of the communication architecture will allow implementing fine per-packet self-optimization of communication services regarding the actual application requirements. A case study showing how this methodology is used by error control mechanisms in the context of wireless networks is presented in order to demonstrate the feasibility and advantages of this approach.

Effectiveness of Adaptive Assessment versus Learner Control in a Multimedia Learning System

Science.gov (United States)

Chen, Ching-Huei; Chang, Shu-Wei

2015-01-01

The purpose of this study was to explore the effectiveness of adaptive assessment versus learner control in a multimedia learning system designed to help secondary students learn science. Unlike other systems, this paper presents a workflow of adaptive assessment following instructional materials that better align with learners' cognitive…

9th International Conference on Multimedia and Ubiquitous Engineering and the 10th International Conference on Future Information Technology

CERN Document Server

Chao, Han-Chieh; Arabnia, Hamid; Yen, Neil; Advanced Multimedia and Ubiquitous Engineering : Future Information Technology; MUE-15; FutureTech 2015

This volume brings together contributions representing the state-of-the-art in new multimedia and future technology information research, currently a major topic in computer science and electronic engineering. Researchers aim to interoperate multimedia frameworks, transforming the way people work and  interact with multimedia data. This book covers future information technology topics including digital and multimedia convergence, ubiquitous and pervasive computing, intelligent computing and applications, embedded systems, mobile and wireless communications, bio-inspired computing, grid and cloud computing, semantic web, human-centric computing and social networks, adaptive and context-aware computing, security and trust computing and related areas.  Representing the combined proceedings of the 9th International Conference on Multimedia and Ubiquitous Engineering (MUE-15) and the 10th International Conference on Future Information Technology (FutureTech 2015), this book aims to provide a complete coverage of...

Simulation of Wireless Digital Communication Systems

Directory of Open Access Journals (Sweden)

A. Mohammed

2004-12-01

Full Text Available Due to the explosive demands for high speed wireless services, suchas wireless Internet, email and cellular video conferencing, digitalwireless communications has become one of the most exciting researchtopics in electrical and electronic engineering field. The never-endingdemand for such personal and multimedia services, however, demandstechnologies operating at higher data rates and broader bandwidths. Inaddition, the complexity of wireless communication and signalprocessing systems has grown considerably during the past decade.Therefore, powerful computer­aided techniques are required for theprocess of modeling, designing, analyzing and evaluating theperformance of digital wireless communication systems. In this paper wediscuss the basic propagation mechanisms affecting the performance ofwireless communication systems, and present a simple, powerful andefficient way to simulate digital wireless communication systems usingMatlab. The simulated results are compared with the theoreticalanalysis to validate the simulator. The simulator is useful inevaluating the performance of wireless multimedia services and theassociated signal processing structures and algorithms for current andnext generation wireless mobile communication systems.

Multi-agent Negotiation Mechanisms for Statistical Target Classification in Wireless Multimedia Sensor Networks

Directory of Open Access Journals (Sweden)

Sheng Wang

2007-10-01

Full Text Available The recent availability of low cost and miniaturized hardware has allowedwireless sensor networks (WSNs to retrieve audio and video data in real worldapplications, which has fostered the development of wireless multimedia sensor networks(WMSNs. Resource constraints and challenging multimedia data volume makedevelopment of efficient algorithms to perform in-network processing of multimediacontents imperative. This paper proposes solving problems in the domain of WMSNs fromthe perspective of multi-agent systems. The multi-agent framework enables flexible networkconfiguration and efficient collaborative in-network processing. The focus is placed ontarget classification in WMSNs where audio information is retrieved by microphones. Todeal with the uncertainties related to audio information retrieval, the statistical approachesof power spectral density estimates, principal component analysis and Gaussian processclassification are employed. A multi-agent negotiation mechanism is specially developed toefficiently utilize limited resources and simultaneously enhance classification accuracy andreliability. The negotiation is composed of two phases, where an auction based approach isfirst exploited to allocate the classification task among the agents and then individual agentdecisions are combined by the committee decision mechanism. Simulation experiments withreal world data are conducted and the results show that the proposed statistical approachesand negotiation mechanism not only reduce memory and computation requi

An efficient and secure partial image encryption for wireless multimedia sensor networks using discrete wavelet transform, chaotic maps and substitution box

Science.gov (United States)

Khan, Muazzam A.; Ahmad, Jawad; Javaid, Qaisar; Saqib, Nazar A.

2017-03-01

Wireless Sensor Networks (WSN) is widely deployed in monitoring of some physical activity and/or environmental conditions. Data gathered from WSN is transmitted via network to a central location for further processing. Numerous applications of WSN can be found in smart homes, intelligent buildings, health care, energy efficient smart grids and industrial control systems. In recent years, computer scientists has focused towards findings more applications of WSN in multimedia technologies, i.e. audio, video and digital images. Due to bulky nature of multimedia data, WSN process a large volume of multimedia data which significantly increases computational complexity and hence reduces battery time. With respect to battery life constraints, image compression in addition with secure transmission over a wide ranged sensor network is an emerging and challenging task in Wireless Multimedia Sensor Networks. Due to the open nature of the Internet, transmission of data must be secure through a process known as encryption. As a result, there is an intensive demand for such schemes that is energy efficient as well as highly secure since decades. In this paper, discrete wavelet-based partial image encryption scheme using hashing algorithm, chaotic maps and Hussain's S-Box is reported. The plaintext image is compressed via discrete wavelet transform and then the image is shuffled column-wise and row wise-wise via Piece-wise Linear Chaotic Map (PWLCM) and Nonlinear Chaotic Algorithm, respectively. To get higher security, initial conditions for PWLCM are made dependent on hash function. The permuted image is bitwise XORed with random matrix generated from Intertwining Logistic map. To enhance the security further, final ciphertext is obtained after substituting all elements with Hussain's substitution box. Experimental and statistical results confirm the strength of the anticipated scheme.

Cross-Layer Adaptive Feedback Scheduling of Wireless Control Systems

Science.gov (United States)

Xia, Feng; Ma, Longhua; Peng, Chen; Sun, Youxian; Dong, Jinxiang

2008-01-01

There is a trend towards using wireless technologies in networked control systems. However, the adverse properties of the radio channels make it difficult to design and implement control systems in wireless environments. To attack the uncertainty in available communication resources in wireless control systems closed over WLAN, a cross-layer adaptive feedback scheduling (CLAFS) scheme is developed, which takes advantage of the co-design of control and wireless communications. By exploiting cross-layer design, CLAFS adjusts the sampling periods of control systems at the application layer based on information about deadline miss ratio and transmission rate from the physical layer. Within the framework of feedback scheduling, the control performance is maximized through controlling the deadline miss ratio. Key design parameters of the feedback scheduler are adapted to dynamic changes in the channel condition. An event-driven invocation mechanism for the feedback scheduler is also developed. Simulation results show that the proposed approach is efficient in dealing with channel capacity variations and noise interference, thus providing an enabling technology for control over WLAN. PMID:27879934

Cross-Layer Adaptive Feedback Scheduling of Wireless Control Systems

Directory of Open Access Journals (Sweden)

Jinxiang Dong

2008-07-01

Full Text Available There is a trend towards using wireless technologies in networked control systems. However, the adverse properties of the radio channels make it difficult to design and implement control systems in wireless environments. To attack the uncertainty in available communication resources in wireless control systems closed over WLAN, a cross-layer adaptive feedback scheduling (CLAFS scheme is developed, which takes advantage of the co-design of control and wireless communications. By exploiting crosslayer design, CLAFS adjusts the sampling periods of control systems at the application layer based on information about deadline miss ratio and transmission rate from the physical layer. Within the framework of feedback scheduling, the control performance is maximized through controlling the deadline miss ratio. Key design parameters of the feedback scheduler are adapted to dynamic changes in the channel condition. An eventdriven invocation mechanism for the feedback scheduler is also developed. Simulation results show that the proposed approach is efficient in dealing with channel capacity variations and noise interference, thus providing an enabling technology for control over WLAN.

Resource optimized TTSH-URA for multimedia stream authentication in swallowable-capsule-based wireless body sensor networks.

Science.gov (United States)

Wang, Wei; Wang, Chunqiu; Zhao, Min

2014-03-01

To ease the burdens on the hospitalization capacity, an emerging swallowable-capsule technology has evolved to serve as a remote gastrointestinal (GI) disease examination technique with the aid of the wireless body sensor network (WBSN). Secure multimedia transmission in such a swallowable-capsule-based WBSN faces critical challenges including energy efficiency and content quality guarantee. In this paper, we propose a joint resource allocation and stream authentication scheme to maintain the best possible video quality while ensuring security and energy efficiency in GI-WBSNs. The contribution of this research is twofold. First, we establish a unique signature-hash (S-H) diversity approach in the authentication domain to optimize video authentication robustness and the authentication bit rate overhead over a wireless channel. Based on the full exploration of S-H authentication diversity, we propose a new two-tier signature-hash (TTSH) stream authentication scheme to improve the video quality by reducing authentication dependence overhead while protecting its integrity. Second, we propose to combine this authentication scheme with a unique S-H oriented unequal resource allocation (URA) scheme to improve the energy-distortion-authentication performance of wireless video delivery in GI-WBSN. Our analysis and simulation results demonstrate that the proposed TTSH with URA scheme achieves considerable gain in both authenticated video quality and energy efficiency.

Real-Time QoS Routing Protocols in Wireless Multimedia Sensor Networks: Study and Analysis.

Science.gov (United States)

Alanazi, Adwan; Elleithy, Khaled

2015-09-02

Many routing protocols have been proposed for wireless sensor networks. These routing protocols are almost always based on energy efficiency. However, recent advances in complementary metal-oxide semiconductor (CMOS) cameras and small microphones have led to the development of Wireless Multimedia Sensor Networks (WMSN) as a class of wireless sensor networks which pose additional challenges. The transmission of imaging and video data needs routing protocols with both energy efficiency and Quality of Service (QoS) characteristics in order to guarantee the efficient use of the sensor nodes and effective access to the collected data. Also, with integration of real time applications in Wireless Senor Networks (WSNs), the use of QoS routing protocols is not only becoming a significant topic, but is also gaining the attention of researchers. In designing an efficient QoS routing protocol, the reliability and guarantee of end-to-end delay are critical events while conserving energy. Thus, considerable research has been focused on designing energy efficient and robust QoS routing protocols. In this paper, we present a state of the art research work based on real-time QoS routing protocols for WMSNs that have already been proposed. This paper categorizes the real-time QoS routing protocols into probabilistic and deterministic protocols. In addition, both categories are classified into soft and hard real time protocols by highlighting the QoS issues including the limitations and features of each protocol. Furthermore, we have compared the performance of mobility-aware query based real-time QoS routing protocols from each category using Network Simulator-2 (NS2). This paper also focuses on the design challenges and future research directions as well as highlights the characteristics of each QoS routing protocol.

Multimedia transmission in MC-CDMA using adaptive subcarrier power allocation and CFO compensation

Science.gov (United States)

Chitra, S.; Kumaratharan, N.

2018-02-01

Multicarrier code division multiple access (MC-CDMA) system is one of the most effective techniques in fourth-generation (4G) wireless technology, due to its high data rate, high spectral efficiency and resistance to multipath fading. However, MC-CDMA systems are greatly deteriorated by carrier frequency offset (CFO) which is due to Doppler shift and oscillator instabilities. It leads to loss of orthogonality among the subcarriers and causes intercarrier interference (ICI). Water filling algorithm (WFA) is an efficient resource allocation algorithm to solve the power utilisation problems among the subcarriers in time-dispersive channels. The conventional WFA fails to consider the effect of CFO. To perform subcarrier power allocation with reduced CFO and to improve the capacity of MC-CDMA system, residual CFO compensated adaptive subcarrier power allocation algorithm is proposed in this paper. The proposed technique allocates power only to subcarriers with high channel to noise power ratio. The performance of the proposed method is evaluated using random binary data and image as source inputs. Simulation results depict that the bit error rate performance and ICI reduction capability of the proposed modified WFA offered superior performance in both power allocation and image compression for high-quality multimedia transmission in the presence of CFO and imperfect channel state information conditions.

Research on quality metrics of wireless adaptive video streaming

Science.gov (United States)

Li, Xuefei

2018-04-01

With the development of wireless networks and intelligent terminals, video traffic has increased dramatically. Adaptive video streaming has become one of the most promising video transmission technologies. For this type of service, a good QoS (Quality of Service) of wireless network does not always guarantee that all customers have good experience. Thus, new quality metrics have been widely studies recently. Taking this into account, the objective of this paper is to investigate the quality metrics of wireless adaptive video streaming. In this paper, a wireless video streaming simulation platform with DASH mechanism and multi-rate video generator is established. Based on this platform, PSNR model, SSIM model and Quality Level model are implemented. Quality Level Model considers the QoE (Quality of Experience) factors such as image quality, stalling and switching frequency while PSNR Model and SSIM Model mainly consider the quality of the video. To evaluate the performance of these QoE models, three performance metrics (SROCC, PLCC and RMSE) which are used to make a comparison of subjective and predicted MOS (Mean Opinion Score) are calculated. From these performance metrics, the monotonicity, linearity and accuracy of these quality metrics can be observed.

Data converters for wireless standards

CERN Document Server

Shi, Chunlei

2002-01-01

Wireless communication is witnessing tremendous growth with proliferation of different standards covering wide, local and personal area networks (WAN, LAN and PAN). The trends call for designs that allow 1) smooth migration to future generations of wireless standards with higher data rates for multimedia applications, 2) convergence of wireless services allowing access to different standards from the same wireless device, 3) inter-continental roaming. This requires designs that work across multiple wireless standards, can easily be reused, achieve maximum hardware share at a minimum power consumption levels particularly for mobile battery-operated devices.

An Image Compression Scheme in Wireless Multimedia Sensor Networks Based on NMF

Directory of Open Access Journals (Sweden)

Shikang Kong

2017-02-01

Full Text Available With the goal of addressing the issue of image compression in wireless multimedia sensor networks with high recovered quality and low energy consumption, an image compression and transmission scheme based on non-negative matrix factorization (NMF is proposed in this paper. First, the NMF algorithm theory is studied. Then, a collaborative mechanism of image capture, block, compression and transmission is completed. Camera nodes capture images and send them to ordinary nodes which use an NMF algorithm for image compression. Compressed images are transmitted to the station by the cluster head node and received from ordinary nodes. The station takes on the image restoration. Simulation results show that, compared with the JPEG2000 and singular value decomposition (SVD compression schemes, the proposed scheme has a higher quality of recovered images and lower total node energy consumption. It is beneficial to reduce the burden of energy consumption and prolong the life of the whole network system, which has great significance for practical applications of WMSNs.

Cross-Layer Techniques for Adaptive Video Streaming over Wireless Networks

Directory of Open Access Journals (Sweden)

Yufeng Shan

2005-02-01

Full Text Available Real-time streaming media over wireless networks is a challenging proposition due to the characteristics of video data and wireless channels. In this paper, we propose a set of cross-layer techniques for adaptive real-time video streaming over wireless networks. The adaptation is done with respect to both channel and data. The proposed novel packetization scheme constructs the application layer packet in such a way that it is decomposed exactly into an integer number of equal-sized radio link protocol (RLP packets. FEC codes are applied within an application packet at the RLP packet level rather than across different application packets and thus reduce delay at the receiver. A priority-based ARQ, together with a scheduling algorithm, is applied at the application layer to retransmit only the corrupted RLP packets within an application layer packet. Our approach combines the flexibility and programmability of application layer adaptations, with low delay and bandwidth efficiency of link layer techniques. Socket-level simulations are presented to verify the effectiveness of our approach.

Performance Evaluation of IP Based Multimedia Services in UMTS

Directory of Open Access Journals (Sweden)

Riri Fitri SARI

2008-01-01

Full Text Available This paper presents our work in the performance evaluation of UMTS network based on simulation. Enhanced UMTS Radio Access Network Extensions for NS-2 (EURANE developed by SEACORN has brought us to the higher phase of UMTS simulation in third generation wireless telecommunication system. Wireless 3G is designed to be able to deliver various kind of multimedia package through an IP network for the purpose of easier interconnection with fixed network with various existing multimedia services. Multimedia services with their bandwidth consumption characteristics are able to be sent through a UMTS network with the existence of High Speed Data Packet Access (HSPDA in Release 5. Quality of Service (QoS is a major concern in multimedia services. This paper shows the performance analysis of a number of multimedia services and their QoS using HSDPA in UMTS. The experiments were based on EURANE extension for NS-2. From the simulation conducted, we found that Unacknowledged Mode (UM in Radio Link Control (RLC will perform better for QoS class number 1 (VoIP and 2 (Video Streaming, while Acknowledged Mode (AM mode are more suitable for QoS class number 3 (web server and 4 (FTP.

Multihoming for Mobile Internet of Multimedia Things

OpenAIRE

Balan, Titus; Robu, Dan; Sandu, Florin

2017-01-01

Mobility, redundancy, and bandwidth requirements are transforming the communication models used for IoT, mainly in case of Critical Communications and multimedia streaming (“IoMT, Internet of Multimedia Things”), as wireless video traffic is expected to be 60–75% of the global mobile traffic by 2020. One of the characteristics of 5G networks will be the proliferation of different/heterogeneous radio networks (virtualized radio access networks, RAN, new energy-efficient radios, femtocells, and...

Presence in the IP multimedia subsystem

NARCIS (Netherlands)

Lin, L.; Liotta, A.

2007-01-01

With an ever increasing penetration of Internet Protocol (IP) technologies, the wireless industry is evolving the mobile core network towards all-IP network. The IP Multimedia Subsystem (IMS) is a standardised Next Generation Network (NGN) architectural framework defined by the 3rd Generation

Lifetime Maximizing Adaptive Power Control in Wireless Sensor Networks

National Research Council Canada - National Science Library

Sun, Fangting; Shayman, Mark

2006-01-01

...: adaptive power control. They focus on the sensor networks that consist of a sink and a set of homogeneous wireless sensor nodes, which are randomly deployed according to a uniform distribution...

Liquid-crystal intraocular adaptive lens with wireless control

NARCIS (Netherlands)

Simonov, A.N.; Vdovine, G.V.; Loktev, M.

2007-01-01

We present a prototype of an adaptive intraocular lens based on a modal liquid-crystal spatial phase modulator with wireless control. The modal corrector consists of a nematic liquid-crystal layer sandwiched between two glass substrates with transparent low- and high-ohmic electrodes, respectively.

Adaptive Probabilistic Routing in Wireless Ad Hoc Networks

OpenAIRE

Hasan, Affaf; Liaqat, Ismail

2013-01-01

The goal of this thesis work is to analyze how design elements and wireless attributes affect opportunistic routing, and in this context develop a new protocol. The algorithm developed aims to improve opportunistic elements in comparison to a well-known opportunistic protocol Simple Opportunistic Adaptive Routing (SOAR).

Combination Adaptive Traffic Algorithm and Coordinated Sleeping in Wireless Sensor Network

Directory of Open Access Journals (Sweden)

M. Udin Harun Al Rasyid

2014-12-01

Full Text Available Wireless sensor network (WSN uses a battery as its primary power source, so that WSN will be limited to battery power for long operations. The WSN should be able to save the energy consumption in order to operate in a long time.WSN has the potential to be the future of wireless communications solutions. WSN are small but has a variety of functions that can help human life. WSN has the wide variety of sensors and can communicate quickly making it easier for people to obtain information accurately and quickly. In this study, we combine adaptive traffic algorithms and coordinated sleeping as power‐efficient WSN solution. We compared the performance of our proposed ideas combination adaptive traffic and coordinated sleeping algorithm with non‐adaptive scheme. From the simulation results, our proposed idea has good‐quality data transmission and more efficient in energy consumption, but it has higher delay than that of non‐adaptive scheme. Keywords:WSN,adaptive traffic,coordinated sleeping,beacon order,superframe order.

A Spike Neural Controller for Traffic Load Parameter with Priority-Based Rate in Wireless Multimedia Sensor Networks

Directory of Open Access Journals (Sweden)

Nadia Adnan Shiltagh

2015-11-01

Full Text Available Wireless Multimedia Sensor Networks (WMSNs are a type of sensor network that contains sensor nodes equipped with cameras, microphones; therefore the WMSNS are able to produce multimedia data such as video and audio streams, still images, and scalar data from the surrounding environment. Most multimedia applications typically produce huge volumes of data, this leads to congestion. To address this challenge, This paper proposes Modify Spike Neural Network control for Traffic Load Parameter with Exponential Weight of Priority Based Rate Control algorithm (MSNTLP with EWBPRC. The Modify Spike Neural Network controller (MSNC can calculate the appropriate traffic load parameter μ for each parent node and then use in the EWPBRC algorithm to estimate the transmission rate of parent nodes and then assign a suitable transmission rate for each child node. A comparative study between (MSNTLP with EWBPRC and fuzzy logic controller for traffic load parameter with Exponential Weight of Priority Based Rate Control algorithm (FTLP with EWBPRC algorithm shows that the (MSNTLP with EWBPRC is more efficient than (FTLP with EWBPRC algorithm in terms of packet loss, queue delay and throughput. Another comparative study between (MSNTLP with EWBPRC and EWBPRC with fixed traffic load parameter (µ shows that the MSNTLP with EWBPRC is more efficient than EWBPRC with fixed traffic load parameter (µ in terms of packet loss ratio and queue delay. A simulation process is developed and tested using the network simulator _2 (NS2 in a computer having the following properties: windows 7 (64-bit, core i7, RAM 8GB, hard 1TB.

Adaptive LINE-P: An Adaptive Linear Energy Prediction Model for Wireless Sensor Network Nodes.

Science.gov (United States)

Ahmed, Faisal; Tamberg, Gert; Le Moullec, Yannick; Annus, Paul

2018-04-05

In the context of wireless sensor networks, energy prediction models are increasingly useful tools that can facilitate the power management of the wireless sensor network (WSN) nodes. However, most of the existing models suffer from the so-called fixed weighting parameter, which limits their applicability when it comes to, e.g., solar energy harvesters with varying characteristics. Thus, in this article we propose the Adaptive LINE-P (all cases) model that calculates adaptive weighting parameters based on the stored energy profiles. Furthermore, we also present a profile compression method to reduce the memory requirements. To determine the performance of our proposed model, we have used real data for the solar and wind energy profiles. The simulation results show that our model achieves 90-94% accuracy and that the compressed method reduces memory overheads by 50% as compared to state-of-the-art models.

Multimedia Technologies for Training: An Introduction.

Science.gov (United States)

Barron, Ann E.; Orwig, Gary W.

This guide introduces trainers, managers, and educators to a variety of new multimedia technologies now being used for presentation and training in business, military, and academic settings. The text describes advances in and implementation of technologies that range from wireless local area networks (LANs) and high definition television (HDTV) to…

A Survey on Content Adaptation Systems towards Energy Consumption Awareness

Directory of Open Access Journals (Sweden)

Mohd Norasri Ismail

2013-01-01

Full Text Available The availability of heterogeneous devices has rapidly changed the way people access the World Wide Web that includes rich content applications such as video streaming, 3D games, video conferencing, and mobile TV. However, most of these devices' (i.e., mobile phone, PDA, smartphone, and tablet capabilities differ in terms of built-in software and library (what they can display, display size (how the content appears, and battery supply (how long the content can be displayed. In order for the digital contents to fit the target device, content adaptation is required. There have been many projects focused on energy-aware-based content adaptation that have been designed with different goals and approaches. This paper reviews some of the representative content adaptation solutions that have been proposed during the last few years, in relation to energy consumption focusing on wireless multimedia streaming in mobile devices. Also, this paper categorizes the research work according to different classifications of multimedia content adaptation requirements. In addition, we discuss some energy-related challenges content adaptation systems.

Content-Aware Video Adaptation under Low-Bitrate Constraint

Directory of Open Access Journals (Sweden)

Hsiao Ming-Ho

2007-01-01

Full Text Available With the development of wireless network and the improvement of mobile device capability, video streaming is more and more widespread in such an environment. Under the condition of limited resource and inherent constraints, appropriate video adaptations have become one of the most important and challenging issues in wireless multimedia applications. In this paper, we propose a novel content-aware video adaptation in order to effectively utilize resource and improve visual perceptual quality. First, the attention model is derived from analyzing the characteristics of brightness, location, motion vector, and energy features in compressed domain to reduce computation complexity. Then, through the integration of attention model, capability of client device and correlational statistic model, attractive regions of video scenes are derived. The information object- (IOB- weighted rate distortion model is used for adjusting the bit allocation. Finally, the video adaptation scheme dynamically adjusts video bitstream in frame level and object level. Experimental results validate that the proposed scheme achieves better visual quality effectively and efficiently.

Novel Adaptive QoS Framework for Integrated UMTS/WLAN Environment

Directory of Open Access Journals (Sweden)

T. Shuminoski

2013-06-01

Full Text Available Since Quality of Service (QoS provisioning for multimedia traffic in integrated Wireless and Mobile Networks is becoming an increasingly important objective, in this paper we introduce a novel concept of an adaptive QoS cross-layer framework. The Adaptive QoS framework is proven via novel simulation results in integrated environment with UMTS and IEEE 802.11 networks. The aim of our novel framework is presenting a new module that shall provide the best QoS and lower cost for a given service using one or more wireless technologies in a given time. The analysis of simulation results has shown superior performances with a high level of QoS provisioning in a variety of network conditions. The performance of Adaptive QoS algorithm is evaluated using ns-miracle augmented with our dual-mode Mobile Equipments (MEs and using statistical analysis.

65 nm LP/GP mix low cost platform for multi-media wireless and consumer applications

Science.gov (United States)

Tavel, B.; Duriez, B.; Gwoziecki, R.; Basso, M. T.; Julien, C.; Ortolland, C.; Laplanche, Y.; Fox, R.; Sabouret, E.; Detcheverry, C.; Boeuf, F.; Morin, P.; Barge, D.; Bidaud, M.; Biénacel, J.; Garnier, P.; Cooper, K.; Chapon, J. D.; Trouiller, Y.; Belledent, J.; Broekaart, M.; Gouraud, P.; Denais, M.; Huard, V.; Rochereau, K.; Difrenza, R.; Planes, N.; Marin, M.; Boret, S.; Gloria, D.; Vanbergue, S.; Abramowitz, P.; Vishnubhotla, L.; Reber, D.; Stolk, P.; Woo, M.; Arnaud, F.

2006-04-01

A complete 65 nm CMOS platform, called LP/GP Mix, has been developed employing thick oxide transistor (IO), Low Power (LP) and General Purpose (GP) devices on the same chip. Dedicated to wireless multi-media and consumer applications, this new triple gate oxide platform is low cost (+1mask only) and saves over 35% of dynamic power with the use of the low operating voltage GP. The LP/GP mix shows competitive digital performance with a ring oscillator (FO = 1) speed equal to 7 ps per stage (GP) and 6T-SRAM static power lower than 10 pA/cell (LP). Compatible with mixed-signal design requirements, transistors show high voltage gain, low mismatch factor and low flicker noise. Moreover, to address mobile phone demands, excellent RF performance has been achieved with FT = 160 GHz for LP and 280 GHz for GP nMOS transistors.

Dynamic QoS Evaluation of Multimedia Contents in Wireless Networks by “Double-Boomerang” Watermarking

Directory of Open Access Journals (Sweden)

Gaetano Giunta

2010-03-01

Full Text Available This work presents a cooperative network-aware processing of multimedia content for dynamic quality of service management in wireless IP networks. Our technique can be also used for quality control in UMTS environments, exploiting the tracing watermarking recently introduced in literature. In this work, we use the transmitted video-sequences to monitor the QoS in a videoconference call. The video-sequence of every active user travels on the communication link, one time as video (transparent mode, one time as watermark (hidden mode describing a boomerang trajectory. The results obtained through our simulation trials confirm the validity of such approach. In fact, the advantages of distributing the management process are (i an easier and more precise localization of the cause of QoS problems, (ii a better knowledge of local situations, (iii a lower complexity for a single QoS agent and (iv an increase in possible actions.

Adaptive Space-Time, Processing for High Performance, Robust Military Wireless Communications

National Research Council Canada - National Science Library

Haimovich, Alexander

2000-01-01

...: (I) performance of adaptive arrays for wireless communications over fading channels in the presence of cochannel interference particularly the case when the number of interference sources exceeds...

Adaptive Priority-Based Downlink Scheduling for WiMAX Networks

OpenAIRE

Wu, Shih-Jung; Huang, Shih-Yi; Huang, Kuo-Feng

2012-01-01

Supporting quality of service (QoS) guarantees for diverse multimedia services are the primary concerns for WiMAX (IEEE 802.16) networks. A scheduling scheme that satisfies QoS requirements has become more important for wireless communications. We propose a downlink scheduling scheme called adaptive priority-based downlink scheduling (APDS) for providing QoS guarantees in IEEE 802.16 networks. APDS comprises two major components: priority assignment and resource allocation. Different service-...

Play It Again, Sam! Adapting Common Games into Multimedia Models Used for Student Reviews.

Science.gov (United States)

Metcalf, Karen K.; Barlow, Amy; Hudson, Lisa; Jones, Elizabeth; Lyons, Dennis; Piersall, James; Munfus, Laureen

1998-01-01

Provides guidelines on how to adapt common games such as checkers, tic tac toe, obstacle courses, and memory joggers into interactive games in multimedia courseware. Emphasizes creating generic games that can be recycled and used for multiple topics to save development time and keep costs low. Discusses topic themes, game structure, and…

Adapting cognitive radio technology for low-power wireless personal area network devices

DEFF Research Database (Denmark)

Toftegaard, Thomas Skjødeberg; Rohde, John

2011-01-01

The application of wireless personal area network (WPAN) and simple point-to-point wireless communication devices has increased drastically both in private household and in our workspaces in general over the last decade. Combined with the fact that the total number of wireless devices...... and associated standards present in the wireless environment is experiencing an extreme growth, the frequency spectrum scarcity is exposed as a severe challenge. Setting up efficient and reliable wireless WPAN links can be challenging even today. This is especially true because of the intensive use...... discusses the challenges associated with the implementation of highly reliable low-power WPAN networks for the future and the adaption of Cognitive Radio technology as a potential solution. A brief status on the maturity of CR technology will be presented as an integral part of this discussion....

Optimal and Fair Resource Allocation for Multiuser Wireless Multimedia Transmissions

Directory of Open Access Journals (Sweden)

Zhangyu Guan

2009-01-01

Full Text Available This paper presents an optimal and fair strategy for multiuser multimedia radio resource allocation (RRA based on coopetition, which suggests a judicious mixture of competition and cooperation. We formulate the co-opetition strategy as sum utility maximization at constraints from both Physical (PHY and Application (APP layers. We show that the maximization can be solved efficiently employing the well-defined Layering as Optimization Decomposition (LOD method. Moreover, the coopetition strategy is applied to power allocation among multiple video users, and evaluated through comparing with existing- competition based strategy. Numerical results indicate that, the co-opetition strategy adapts the best to the changes of network conditions, participating users, and so forth. It is also shown that the coopetition can lead to an improved number of satisfied users, and in the meanwhile provide more flexible tradeoff between system efficiency and fairness among users.

Interference mitigation through adaptive power control in wireless sensor networks

NARCIS (Netherlands)

Chincoli, M.; Bacchiani, C.; Syed, Aly; Exarchakos, G.; Liotta, A.

2016-01-01

Adaptive transmission power control schemes have been introduced in wireless sensor networks to adjust energy consumption under different network conditions. This is a crucial goal, given the constraints under which sensor communications operate. Power reduction may however have counter-productive

Distribution of Multimedia Streams to Mobile Internet Users

NARCIS (Netherlands)

Hesselman, C.E.W.

2005-01-01

In this thesis, we consider the efficient distribution of live and scheduled multimedia content (e.g., radio and TV broadcasts) to mobile users via a ubiquitous wireless Internet. The objective is to design and develop a content delivery system that (1) enables content owners to deliver their

Providing QoS through machine-learning-driven adaptive multimedia applications.

Science.gov (United States)

Ruiz, Pedro M; Botía, Juan A; Gómez-Skarmeta, Antonio

2004-06-01

We investigate the optimization of the quality of service (QoS) offered by real-time multimedia adaptive applications through machine learning algorithms. These applications are able to adapt in real time their internal settings (i.e., video sizes, audio and video codecs, among others) to the unpredictably changing capacity of the network. Traditional adaptive applications just select a set of settings to consume less than the available bandwidth. We propose a novel approach in which the selected set of settings is the one which offers a better user-perceived QoS among all those combinations which satisfy the bandwidth restrictions. We use a genetic algorithm to decide when to trigger the adaptation process depending on the network conditions (i.e., loss-rate, jitter, etc.). Additionally, the selection of the new set of settings is done according to a set of rules which model the user-perceived QoS. These rules are learned using the SLIPPER rule induction algorithm over a set of examples extracted from scores provided by real users. We will demonstrate that the proposed approach guarantees a good user-perceived QoS even when the network conditions are constantly changing.

Energy-efficient Organization of Wireless Sensor Networks with Adaptive Forecasting

Directory of Open Access Journals (Sweden)

Dao-Wei Bi

2008-04-01

Full Text Available Due to the wide potential applications of wireless sensor networks, this topic has attracted great attention. The strict energy constraints of sensor nodes result in great challenges for energy efficiency. This paper proposes an energy-efficient organization method. The organization of wireless sensor networks is formulated for target tracking. Target localization is achieved by collaborative sensing with multi-sensor fusion. The historical localization results are utilized for adaptive target trajectory forecasting. Combining autoregressive moving average (ARMA model and radial basis function networks (RBFNs, robust target position forecasting is performed. Moreover, an energyefficient organization method is presented to enhance the energy efficiency of wireless sensor networks. The sensor nodes implement sensing tasks are awakened in a distributed manner. When the sensor nodes transfer their observations to achieve data fusion, the routing scheme is obtained by ant colony optimization. Thus, both the operation and communication energy consumption can be minimized. Experimental results verify that the combination of ARMA model and RBFN can estimate the target position efficiently and energy saving is achieved by the proposed organization method in wireless sensor networks.

Scalable Video Streaming in Wireless Mesh Networks for Education

Science.gov (United States)

Liu, Yan; Wang, Xinheng; Zhao, Liqiang

2011-01-01

In this paper, a video streaming system for education based on a wireless mesh network is proposed. A wireless mesh network is a self-organizing, self-managing and reliable intelligent network, which allows educators to deploy a network quickly. Video streaming plays an important role in this system for multimedia data transmission. This new…

Conventional to Cloud: Detailed survey and comparative study of multimedia streaming rate Adaptation

OpenAIRE

Selvaraj Kesavan; Jayakumar J

2014-01-01

Infotainment and telecommunication industry is fast evolving towards personalized network connectivity and newer applications services ranging from music playback to ever changing telephony applications. Streaming is the key services which enables the users to view real time multimedia content on-the-go anywhere and everywhere. In streaming, quality of service is a major concern in the increasing network traffic and high user demand. Rate adaptation is crucial process to dynamically evaluate,...

Intelligent techniques in signal processing for multimedia security

CERN Document Server

Santhi, V

2017-01-01

This book proposes new algorithms to ensure secured communications and prevent unauthorized data exchange in secured multimedia systems. Focusing on numerous applications’ algorithms and scenarios, it offers an in-depth analysis of data hiding technologies including watermarking, cryptography, encryption, copy control, and authentication. The authors present a framework for visual data hiding technologies that resolves emerging problems of modern multimedia applications in several contexts including the medical, healthcare, education, and wireless communication networking domains. Further, it introduces several intelligent security techniques with real-time implementation. As part of its comprehensive coverage, the book discusses contemporary multimedia authentication and fingerprinting techniques, while also proposing personal authentication/recognition systems based on hand images, surveillance system security using gait recognition, face recognition under restricted constraints such as dry/wet face condi...

New Trends on Ubiquitous Mobile Multimedia Applications

Directory of Open Access Journals (Sweden)

Oliveira Marco

2010-01-01

Full Text Available Mobile devices present the opportunity to enhance our fast-growing and globally connected society, improving user-experience through novel approaches for information dissemination through mobile communication. The research community is developing new technologies, services, and applications to enable ubiquitous environments based on mobile technology. This paper tackles several important challenges such as communication cost and device limitations for development of ubiquitous multimedia applications. And we propose a system for news delivery using a set of wireless multimedia applications. For this purpose, we have performed a case study with Apple iPhone's platform, featuring two multimedia application contexts, namely, Web and native applications. The multimedia mobile applications draw on iPhone's assets, enabling context-awareness to distribute news, improving communication efficiency and setting-up viewing optimizations, thus enhancing user-experience. The proposed system is evaluated and validated through a series of real-life experiments on real devices, with online full availability. Moreover, due to the Web application availability, the system is not restrained to Apple's iPhone platform, but can also benefit users with other devices.

3D Integration for Wireless Multimedia

Science.gov (United States)

Kimmich, Georg

The convergence of mobile phone, internet, mapping, gaming and office automation tools with high quality video and still imaging capture capability is becoming a strong market trend for portable devices. High-density video encode and decode, 3D graphics for gaming, increased application-software complexity and ultra-high-bandwidth 4G modem technologies are driving the CPU performance and memory bandwidth requirements close to the PC segment. These portable multimedia devices are battery operated, which requires the deployment of new low-power-optimized silicon process technologies and ultra-low-power design techniques at system, architecture and device level. Mobile devices also need to comply with stringent silicon-area and package-volume constraints. As for all consumer devices, low production cost and fast time-to-volume production is key for success. This chapter shows how 3D architectures can bring a possible breakthrough to meet the conflicting power, performance and area constraints. Multiple 3D die-stacking partitioning strategies are described and analyzed on their potential to improve the overall system power, performance and cost for specific application scenarios. Requirements and maturity of the basic process-technology bricks including through-silicon via (TSV) and die-to-die attachment techniques are reviewed. Finally, we highlight new challenges which will arise with 3D stacking and an outlook on how they may be addressed: Higher power density will require thermal design considerations, new EDA tools will need to be developed to cope with the integration of heterogeneous technologies and to guarantee signal and power integrity across the die stack. The silicon/wafer test strategies have to be adapted to handle high-density IO arrays, ultra-thin wafers and provide built-in self-test of attached memories. New standards and business models have to be developed to allow cost-efficient assembly and testing of devices from different silicon and technology

The Video Collaborative Localization of a Miner's Lamp Based on Wireless Multimedia Sensor Networks for Underground Coal Mines.

Science.gov (United States)

You, Kaiming; Yang, Wei; Han, Ruisong

2015-09-29

Based on wireless multimedia sensor networks (WMSNs) deployed in an underground coal mine, a miner's lamp video collaborative localization algorithm was proposed to locate miners in the scene of insufficient illumination and bifurcated structures of underground tunnels. In bifurcation area, several camera nodes are deployed along the longitudinal direction of tunnels, forming a collaborative cluster in wireless way to monitor and locate miners in underground tunnels. Cap-lamps are regarded as the feature of miners in the scene of insufficient illumination of underground tunnels, which means that miners can be identified by detecting their cap-lamps. A miner's lamp will project mapping points on the imaging plane of collaborative cameras and the coordinates of mapping points are calculated by collaborative cameras. Then, multiple straight lines between the positions of collaborative cameras and their corresponding mapping points are established. To find the three-dimension (3D) coordinate location of the miner's lamp a least square method is proposed to get the optimal intersection of the multiple straight lines. Tests were carried out both in a corridor and a realistic scenario of underground tunnel, which show that the proposed miner's lamp video collaborative localization algorithm has good effectiveness, robustness and localization accuracy in real world conditions of underground tunnels.

Adaptive Media Access Control for Energy Harvesting - Wireless Sensor Networks

DEFF Research Database (Denmark)

Fafoutis, Xenofon; Dragoni, Nicola

2012-01-01

ODMAC (On-Demand Media Access Control) is a recently proposed MAC protocol designed to support individual duty cycles for Energy Harvesting — Wireless Sensor Networks (EH-WSNs). Individual duty cycles are vital for EH-WSNs, because they allow nodes to adapt their energy consumption to the ever-ch...

Adaptive Home System Using Wireless Sensor Network And Multi Agent System

OpenAIRE

Jayarani Kamble; Prof.Nandini Dhole

2014-01-01

Smart Home is an emerging technology growing continuously which includes number of new technologies which helps to improve human’s quality of living. This paper proposes an adaptive home system for optimum utilization of power, through Artificial Intelligence and Wireless Sensor network. Artificial Intelligence is a technology for developing adaptive system that can perceive the enviornmrnt, learn from the environment and can make decision using Rule based system.Zigbee is a w...

BOB-RED queue management for IEEE 802.15.4 wireless sensor networks

Directory of Open Access Journals (Sweden)

Wu Jean-Lien

2011-01-01

Full Text Available Abstract Multimedia services over resource constrained wireless sensor networks (WSNs face a performance bottleneck issue from the gateway node to the sink node. Therefore, the queue management at the gateway node is crucial for diversified messages conveyed from the front nodes to the sink node. In this article, beacon order-based random early detection (BOB-RED queue management is proposed. BOB-RED is a dynamic adaptation scheme based on adjusting beacon interval and superframe duration in the IEEE 802.15.4 MAC superframe accompanied with RED queue management scheme to increase the transmission efficiency of multimedia over WSNs. We focus on the performance improvement upon different traffic loads over WSNs. Evaluation metrics include end-to-end delay, packet delivery ratio, and energy consumption in IEEE 802.15.4 beacon enabled mode. Simulation results show that BOB-RED can effectively decrease end-to-end delay and energy consumption compared to the DropTail scheme.

Introductory survey for wireless infrared communications

Directory of Open Access Journals (Sweden)

Munsif Ali Jatoi

2014-08-01

Full Text Available Wireless infrared communications can be defined as the propagation of light waves in free space using infrared radiation whose range is 400–700 nm. This range corresponds to frequencies of hundreds of terahertz, which is high for higher data rate applications. Wireless infrared is applied for higher data rates applications such as wireless computing, wireless video and wireless multimedia communication applications. Introduced by Gfeller, this field has grown with different link configurations, improved transmitter efficiency, increased receiver responsivity and various multiple access techniques for improved quality. Errors are caused because of background light, which causes degradation overall system performance. Error correction techniques are used to remove the errors caused during transmission. This study provides a brief account on field theory used for error correction in wireless infrared systems. The results are produced in terms of bit error rate and signal-to-noise ratio for various bit lengths to show the ability of encoding and decoding algorithms.

A two-hop based adaptive routing protocol for real-time wireless sensor networks.

Science.gov (United States)

Rachamalla, Sandhya; Kancherla, Anitha Sheela

2016-01-01

One of the most important and challenging issues in wireless sensor networks (WSNs) is to optimally manage the limited energy of nodes without degrading the routing efficiency. In this paper, we propose an energy-efficient adaptive routing mechanism for WSNs, which saves energy of nodes by removing the much delayed packets without degrading the real-time performance of the used routing protocol. It uses the adaptive transmission power algorithm which is based on the attenuation of the wireless link to improve the energy efficiency. The proposed routing mechanism can be associated with any geographic routing protocol and its performance is evaluated by integrating with the well known two-hop based real-time routing protocol, PATH and the resulting protocol is energy-efficient adaptive routing protocol (EE-ARP). The EE-ARP performs well in terms of energy consumption, deadline miss ratio, packet drop and end-to-end delay.

Location-Based Self-Adaptive Routing Algorithm for Wireless Sensor Networks in Home Automation

Directory of Open Access Journals (Sweden)

Hong SeungHo

2011-01-01

Full Text Available The use of wireless sensor networks in home automation (WSNHA is attractive due to their characteristics of self-organization, high sensing fidelity, low cost, and potential for rapid deployment. Although the AODVjr routing algorithm in IEEE 802.15.4/ZigBee and other routing algorithms have been designed for wireless sensor networks, not all are suitable for WSNHA. In this paper, we propose a location-based self-adaptive routing algorithm for WSNHA called WSNHA-LBAR. It confines route discovery flooding to a cylindrical request zone, which reduces the routing overhead and decreases broadcast storm problems in the MAC layer. It also automatically adjusts the size of the request zone using a self-adaptive algorithm based on Bayes' theorem. This makes WSNHA-LBAR more adaptable to the changes of the network state and easier to implement. Simulation results show improved network reliability as well as reduced routing overhead.

The Video Collaborative Localization of a Miner’s Lamp Based on Wireless Multimedia Sensor Networks for Underground Coal Mines

Directory of Open Access Journals (Sweden)

Kaiming You

2015-09-01

Full Text Available Based on wireless multimedia sensor networks (WMSNs deployed in an underground coal mine, a miner’s lamp video collaborative localization algorithm was proposed to locate miners in the scene of insufficient illumination and bifurcated structures of underground tunnels. In bifurcation area, several camera nodes are deployed along the longitudinal direction of tunnels, forming a collaborative cluster in wireless way to monitor and locate miners in underground tunnels. Cap-lamps are regarded as the feature of miners in the scene of insufficient illumination of underground tunnels, which means that miners can be identified by detecting their cap-lamps. A miner’s lamp will project mapping points on the imaging plane of collaborative cameras and the coordinates of mapping points are calculated by collaborative cameras. Then, multiple straight lines between the positions of collaborative cameras and their corresponding mapping points are established. To find the three-dimension (3D coordinate location of the miner’s lamp a least square method is proposed to get the optimal intersection of the multiple straight lines. Tests were carried out both in a corridor and a realistic scenario of underground tunnel, which show that the proposed miner’s lamp video collaborative localization algorithm has good effectiveness, robustness and localization accuracy in real world conditions of underground tunnels.

The Video Collaborative Localization of a Miner’s Lamp Based on Wireless Multimedia Sensor Networks for Underground Coal Mines

Science.gov (United States)

You, Kaiming; Yang, Wei; Han, Ruisong

2015-01-01

Based on wireless multimedia sensor networks (WMSNs) deployed in an underground coal mine, a miner’s lamp video collaborative localization algorithm was proposed to locate miners in the scene of insufficient illumination and bifurcated structures of underground tunnels. In bifurcation area, several camera nodes are deployed along the longitudinal direction of tunnels, forming a collaborative cluster in wireless way to monitor and locate miners in underground tunnels. Cap-lamps are regarded as the feature of miners in the scene of insufficient illumination of underground tunnels, which means that miners can be identified by detecting their cap-lamps. A miner’s lamp will project mapping points on the imaging plane of collaborative cameras and the coordinates of mapping points are calculated by collaborative cameras. Then, multiple straight lines between the positions of collaborative cameras and their corresponding mapping points are established. To find the three-dimension (3D) coordinate location of the miner’s lamp a least square method is proposed to get the optimal intersection of the multiple straight lines. Tests were carried out both in a corridor and a realistic scenario of underground tunnel, which show that the proposed miner’s lamp video collaborative localization algorithm has good effectiveness, robustness and localization accuracy in real world conditions of underground tunnels. PMID:26426023

Integrated resource management for Hybrid Optical Wireless (HOW) networks

DEFF Research Database (Denmark)

Yan, Ying; Yu, Hao; Wessing, Henrik

2009-01-01

Efficient utilization of available bandwidth over hybrid optical wireless networks is a critical issue, especially for multimedia applications with high data rates and stringent Quality of Service (QoS) requirements. In this paper, we propose an integrated resource management including an enhanced...... resource sharing scheme and an integrated admission control scheme for the hybrid optical wireless networks. It provides QoS guarantees for connections through both optical and wireless domain. Simulation results show that our proposed scheme improves QoS performances in terms of high throughput and low...

An Emergency-Adaptive Routing Scheme for Wireless Sensor Networks for Building Fire Hazard Monitoring

Directory of Open Access Journals (Sweden)

Guilin Zheng

2011-03-01

Full Text Available Fire hazard monitoring and evacuation for building environments is a novel application area for the deployment of wireless sensor networks. In this context, adaptive routing is essential in order to ensure safe and timely data delivery in building evacuation and fire fighting resource applications. Existing routing mechanisms for wireless sensor networks are not well suited for building fires, especially as they do not consider critical and dynamic network scenarios. In this paper, an emergency-adaptive, real-time and robust routing protocol is presented for emergency situations such as building fire hazard applications. The protocol adapts to handle dynamic emergency scenarios and works well with the routing hole problem. Theoretical analysis and simulation results indicate that our protocol provides a real-time routing mechanism that is well suited for dynamic emergency scenarios in building fires when compared with other related work.

Adaptive Modulation and Coding for LTE Wireless Communication

Science.gov (United States)

Hadi, S. S.; Tiong, T. C.

2015-04-01

Long Term Evolution (LTE) is the new upgrade path for carrier with both GSM/UMTS networks and CDMA2000 networks. The LTE is targeting to become the first global mobile phone standard regardless of the different LTE frequencies and bands use in other countries barrier. Adaptive Modulation and Coding (AMC) is used to increase the network capacity or downlink data rates. Various modulation types are discussed such as Quadrature Phase Shift Keying (QPSK), Quadrature Amplitude Modulation (QAM). Spatial multiplexing techniques for 4×4 MIMO antenna configuration is studied. With channel station information feedback from the mobile receiver to the base station transmitter, adaptive modulation and coding can be applied to adapt to the mobile wireless channels condition to increase spectral efficiencies without increasing bit error rate in noisy channels. In High-Speed Downlink Packet Access (HSDPA) in Universal Mobile Telecommunications System (UMTS), AMC can be used to choose modulation types and forward error correction (FEC) coding rate.

Resource management for multimedia services in high data rate wireless networks

CERN Document Server

Zhang, Ruonan; Pan, Jianping

2017-01-01

This brief offers a valuable resource on principles of quality-of-service (QoS) provisioning and the related link-layer resource management techniques for high data-rate wireless networks. The primary emphasis is on protocol modeling and analysis. It introduces media access control (MAC) protocols, standards of wireless local area networks (WLANs), wireless personal area networks (WPANs), and wireless body area networks (WBANs), discussing their key technologies, applications, and deployment scenarios. The main analytical approaches and models for performance analysis of the fundamental resource scheduling mechanisms, including the contention-based, reservation-based, and hybrid MAC, are presented. To help readers understand and evaluate system performance, the brief contains a range of simulation results. In addition, a thorough bibliography provides an additional tool. This brief is an essential resource for engineers, researchers, students, and users of wireless networks.

Resource Efficient LDPC Decoders for Multimedia Communication

OpenAIRE

Chandrasetty, Vikram Arkalgud; Aziz, Syed Mahfuzul

2013-01-01

Achieving high image quality is an important aspect in an increasing number of wireless multimedia applications. These applications require resource efficient error correction hardware to detect and correct errors introduced by the communication channel. This paper presents an innovative flexible architecture for error correction using Low-Density Parity-Check (LDPC) codes. The proposed partially-parallel decoder architecture utilizes a novel code construction technique based on multi-level H...

MEDIAN: Wireless broadband LAN for multimedia applications

NARCIS (Netherlands)

Vliet, P.J. van

1998-01-01

MEDIAN is one of the projects in the mobile domain of the Advanced Communications Technologies and Services (ACTS) programme of the European Commission. The main obiective of the MEDIAN project is to evaluate and implement a high speed Wireless Customer Premises / Local Area Network (WCPN/WLAN)

Traffic Adaptive MAC Protocols in Wireless Body Area Networks

Directory of Open Access Journals (Sweden)

Farhan Masud

2017-01-01

Full Text Available In Wireless Body Area Networks (WBANs, every healthcare application that is based on physical sensors is responsible for monitoring the vital signs data of patient. WBANs applications consist of heterogeneous and dynamic traffic loads. Routine patient’s observation is described as low-load traffic while an alarming situation that is unpredictable by nature is referred to as high-load traffic. This paper offers a thematic review of traffic adaptive Medium Access Control (MAC protocols in WBANs. First, we have categorized them based on their goals, methods, and metrics of evaluation. The Zigbee standard IEEE 802.15.4 and the baseline MAC IEEE 802.15.6 are also reviewed in terms of traffic adaptive approaches. Furthermore, a comparative analysis of the protocols is made and their performances are analyzed in terms of delay, packet delivery ratio (PDR, and energy consumption. The literature shows that no review work has been done on traffic adaptive MAC protocols in WBANs. This review work, therefore, could add enhancement to traffic adaptive MAC protocols and will stimulate a better way of solving the traffic adaptivity problem.

Design of novel non-contact multimedia controller for disability by using visual stimulus.

Science.gov (United States)

Pan, Jeng-Shyang; Lo, Chi-Chun; Tsai, Shang-Ho; Lin, Bor-Shyh

2015-12-01

The design of a novel non-contact multimedia controller is proposed in this study. Nowadays, multimedia controllers are generally used by patients and nursing assistants in the hospital. Conventional multimedia controllers usually involve in manual operation or other physical movements. However, it is more difficult for the disabled patients to operate the conventional multimedia controller by themselves; they might totally depend on others. Different from other multimedia controllers, the proposed system provides a novel concept of controlling multimedia via visual stimuli, without manual operation. The disabled patients can easily operate the proposed multimedia system by focusing on the control icons of a visual stimulus device, where a commercial tablet is used as the visual stimulus device. Moreover, a wearable and wireless electroencephalogram (EEG) acquisition device is also designed and implemented to easily monitor the user's EEG signals in daily life. Finally, the proposed system has been validated. The experimental result shows that the proposed system can effectively measure and extract the EEG feature related to visual stimuli, and its information transfer rate is also good. Therefore, the proposed non-contact multimedia controller exactly provides a good prototype of novel multimedia controlling scheme. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Multimedia adaptation with SIP resource availability signalling in IMS-networks

NARCIS (Netherlands)

Ozcelebi, T.; Radovanovic, I.

2007-01-01

Unlicensed, nondedicated and nondeterministic computer access networks are included in IP multimedia subsystem (IMS) in addition to the operator core network, which arises new end-to-end quality-of-service (QoS) issues for multimedia streaming. The resource availability of the network and the

Secure Adaptive Topology Control for Wireless Ad-Hoc Sensor Networks

Directory of Open Access Journals (Sweden)

Yen-Chieh Ouyang

2010-02-01

Full Text Available This paper presents a secure decentralized clustering algorithm for wireless ad-hoc sensor networks. The algorithm operates without a centralized controller, operates asynchronously, and does not require that the location of the sensors be known a priori. Based on the cluster-based topology, secure hierarchical communication protocols and dynamic quarantine strategies are introduced to defend against spam attacks, since this type of attacks can exhaust the energy of sensor nodes and will shorten the lifetime of a sensor network drastically. By adjusting the threshold of infected percentage of the cluster coverage, our scheme can dynamically coordinate the proportion of the quarantine region and adaptively achieve the cluster control and the neighborhood control of attacks. Simulation results show that the proposed approach is feasible and cost effective for wireless sensor networks.

Wireless sensor network adaptive cooling

Energy Technology Data Exchange (ETDEWEB)

Mitchell, T. [SynapSense Corp., Folsom, CA (United States)

2009-07-01

Options for reducing data centre cooling energy requirements and their cost savings were discussed with particular reference to a wireless control solution developed by SynapSense Corporation. The wireless sensor network reduces cooling energy use at data centres by providing improved air flow management through the installation of cold aisle containment. The use of this low cost, non-invasive wireless sensor network has reduced the cooling energy use in a data center at BC Hydro by 30 per cent. The system also reduced the server and storage fan energy by 3 per cent by maintaining inlet air temperature below ASHRAE recommended operating range. The distribution of low power, low cost wireless sensors has enabled visualization tools that are changing the way that data centres are managed. The annual savings have been estimated at 4,560,000 kWh and the annual carbon dioxide abatement is approximately 1,400 metric tons. tabs., figs.

Multihoming for Mobile Internet of Multimedia Things

Directory of Open Access Journals (Sweden)

Titus Balan

2017-01-01

Full Text Available Mobility, redundancy, and bandwidth requirements are transforming the communication models used for IoT, mainly in case of Critical Communications and multimedia streaming (“IoMT, Internet of Multimedia Things”, as wireless video traffic is expected to be 60–75% of the global mobile traffic by 2020. One of the characteristics of 5G networks will be the proliferation of different/heterogeneous radio networks (virtualized radio access networks, RAN, new energy-efficient radios, femtocells, and offloading capabilities and the possibility for IoT objects to connect and load-balance between dual and multiple RANs. This paper focuses on the possibility of using LISP (Locator Identifier Separation Protocol for multihoming and load-balancing purposes and presents an illustrative scenario for the case of mobile IoT (e.g., the “things” part of vehicular or public transportation systems, PTS that are also intensive bandwidth consumers, like the case of connected multimedia “things.” We have implemented and tested a demonstrator of a mobile LISP IoT gateway that is also integrated with Cloud-based video analytics.

Adaptive Multi-Layered Space-Time Block Coded Systems in Wireless Environments

KAUST Repository

Al-Ghadhban, Samir

2014-12-23

© 2014, Springer Science+Business Media New York. Multi-layered space-time block coded systems (MLSTBC) strike a balance between spatial multiplexing and transmit diversity. In this paper, we analyze the block error rate performance of MLSTBC. In addition, we propose an adaptive MLSTBC schemes that are capable of accommodating the channel signal-to-noise ratio variation of wireless systems by near instantaneously adapting the uplink transmission configuration. The main results demonstrate that significant effective throughput improvements can be achieved while maintaining a certain target bit error rate.

Connections for the Digital Age Multimedia Communications for Mobile, Nomadic and Fixed Devices

CERN Document Server

Carne, E Bryan

2011-01-01

Explores and analyzes past and current technologies and trends in multimedia communication Digital natives-those persons born in the digital age-have an ever-widening range of wireless-enabled devices at their disposal. They are the drivers of multimedia communications, continually seeking out the technologies and distribution channels that best match their needs. This book outlines the changes in telecommunications that are occurring to meet these needs. It addresses the continually increasing requirement to provide connections that make the electronic encounter as natural and convenient as p

Specification and Support of Adaptable Networked Multimedia

NARCIS (Netherlands)

D.C.A. Bulterman (Dick)

1993-01-01

htmlabstractAccessing multimedia information in a networked environment introduces problems that don't exist when the same information is accessed locally. These problems include: competing for network resources within and across applications, synchronizing data arrivals from various sources within

Quality-Assured and Sociality-Enriched Multimedia Mobile Mashup

Directory of Open Access Journals (Sweden)

Zhang Hongguang

2010-01-01

Full Text Available Mashups are getting more complex with the addition of rich-media and real-time services. The new research challenges will be how to guarantee the quality of the aggregated services, and how to share them in a collaborative manner. This paper presents a metadata-based mashup framework in Next Generation Wireless Network (NGWN, which guarantees the quality and supports social interactions. In contrast to existing quality-assured approaches, the proposed mashup model addresses the quality management issue from a new perspective through defining the Quality of Service (QoS metadata into two levels: fidelity (user perspective and modality (application perspective. The quality is assured from quality-aware service selection and quality-adaptable service delivery. Furthermore, the mashup model is extended for users to annotate services collaboratively. The annotation occurs in two ways, social tagging (e.g., rating and comments and QoS attributes (e.g., device type and access network, etc.. In order to apply this network-independent metadata model into NGWN architecture, we further introduce a new entity named Multimedia Mashup Engine (MME which enables seamlessly access to the services and Adaptation Decision Taking (ADT. Finally, our prototype system and the simulation results demonstrate the performance of the proposed work.

Delay-aware adaptive sleep mechanism for green wireless-optical broadband access networks

Science.gov (United States)

Wang, Ruyan; Liang, Alei; Wu, Dapeng; Wu, Dalei

2017-07-01

Wireless-Optical Broadband Access Network (WOBAN) is capacity-high, reliable, flexible, and ubiquitous, as it takes full advantage of the merits from both optical communication and wireless communication technologies. Similar to other access networks, the high energy consumption poses a great challenge for building up WOBANs. To shot this problem, we can make some load-light Optical Network Units (ONUs) sleep to reduce the energy consumption. Such operation, however, causes the increased packet delay. Jointly considering the energy consumption and transmission delay, we propose a delay-aware adaptive sleep mechanism. Specifically, we develop a new analytical method to evaluate the transmission delay and queuing delay over the optical part, instead of adopting M/M/1 queuing model. Meanwhile, we also analyze the access delay and queuing delay of the wireless part. Based on such developed delay models, we mathematically derive ONU's optimal sleep time. In addition, we provide numerous simulation results to show the effectiveness of the proposed mechanism.

Towards adaptive security for convergent wireless sensor networks in beyond 3G environments

DEFF Research Database (Denmark)

Mitseva, Anelia; Aivaloglou, Efthimia; Marchitti, Maria-Antonietta

2010-01-01

The integration of wireless sensor networks with different network systems gives rise to many research challenges to ensure security, privacy and trust in the overall architecture. The main contribution of this paper is a generic security, privacy and trust framework providing context-aware adapt...

A Novel Adaptive Modulation Based on Nondata-Aided Error Vector Magnitude in Non-Line-Of-Sight Condition of Wireless Sensor Network.

Science.gov (United States)

Yang, Fan; Zeng, Xiaoping; Mao, Haiwei; Jian, Xin; Tan, Xiaoheng; Du, Derong

2018-01-15

The high demand for multimedia applications in environmental monitoring, invasion detection, and disaster aid has led to the rise of wireless sensor network (WSN). With the increase of reliability and diversity of information streams, the higher requirements on throughput and quality of service (QoS) have been put forward in data transmission between two sensor nodes. However, lower spectral efficiency becomes a bottleneck in non-line-of-sight (NLOS) transmission of WSN. This paper proposes a novel nondata-aided error vector magnitude based adaptive modulation (NDA-EVM-AM) to solve the problem. NDA-EVM is considered as a new metric to evaluate the quality of NLOS link for adaptive modulation in WSN. By modeling the NLOS scenario as the η - μ fading channel, a closed-form expression for the NDA-EVM of multilevel quadrature amplitude modulation (MQAM) signals over the η - μ fading channel is derived, and the relationship between SER and NDA-EVM is also formulated. Based on these results, NDA-EVM state machine is designed for adaptation strategy. The algorithmic complexity of NDA-EVM-AM is analyzed and the outage capacity of NDA-EVM-AM in an NLOS scenario is also given. The performances of NDA-EVM-AM are compared by simulation, and the results show that NDA-EVM-AM is an effective technique to be used in the NLOS scenarios of WSN. This technique can accurately reflect the channel variations and efficiently adjust modulation order to better match the channel conditions, hence, obtaining better performance in average spectral efficiency.

SOMM: A new service oriented middleware for generic wireless multimedia sensor networks based on code mobility.

Science.gov (United States)

Faghih, Mohammad Mehdi; Moghaddam, Mohsen Ebrahimi

2011-01-01

Although much research in the area of Wireless Multimedia Sensor Networks (WMSNs) has been done in recent years, the programming of sensor nodes is still time-consuming and tedious. It requires expertise in low-level programming, mainly because of the use of resource constrained hardware and also the low level API provided by current operating systems. The code of the resulting systems has typically no clear separation between application and system logic. This minimizes the possibility of reusing code and often leads to the necessity of major changes when the underlying platform is changed. In this paper, we present a service oriented middleware named SOMM to support application development for WMSNs. The main goal of SOMM is to enable the development of modifiable and scalable WMSN applications. A network which uses the SOMM is capable of providing multiple services to multiple clients at the same time with the specified Quality of Service (QoS). SOMM uses a virtual machine with the ability to support mobile agents. Services in SOMM are provided by mobile agents and SOMM also provides a t space on each node which agents can use to communicate with each other.

Radio-over-fibre technology for broadband wireless communication systems

NARCIS (Netherlands)

Ng'Oma, A.

2005-01-01

Wireless coverage of the end-user domain, be it outdoors or indoors (in-building), is poised to become an essential part of broadband communication networks. In order to offer integrated broadband services (combining voice, data, video, multimedia services, and new value added services), these

A Rate Adaptation Scheme According to Channel Conditions in Wireless LANs

Science.gov (United States)

Numoto, Daisuke; Inai, Hiroshi

Rate adaptation in wireless LANs is to select the most suitable transmission rate automatically according to channel condition. If the channel condition is good, a station can choose a higher transmission rate, otherwise, it should choose a lower but noise-resistant transmission rate. Since IEEE 802.11 does not specify any rate adaptation scheme, several schemes have been proposed. However those schemes provide low throughput or unfair transmission opportunities among stations especially when the number of stations increases. In this paper, we propose a rate adaptation scheme under which the transmission rate quickly closes and then stays around an optimum rate even in the presence of a large number of stations. Via simulation, our scheme provides higher throughput than existing ones and almost equal fairness.

Multimedia streaming adaptation IMS-networks (Chapter 11)

NARCIS (Netherlands)

Ozcelebi, T.; Radovanovic, I.; Crisan, M.

2010-01-01

Introduction Multimedia services such as video, gaming and music marked the close of the last century and have become inextricably linked with our lives in the current century. The success and popularity of these services was fuelled by the explosive expansion of the Internet and the furious

Cross-layer optimized rate adaptation and scheduling for multiple-user wireless video streaming

NARCIS (Netherlands)

Ozcelebi, T.; Sunay, M.O.; Tekalp, A.M.; Civanlar, M.R.

2007-01-01

We present a cross-layer optimized video rate adaptation and user scheduling scheme for multi-user wireless video streaming aiming for maximum quality of service (QoS) for each user,, maximum system video throughput, and QoS fairness among users. These objectives are jointly optimized using a

Implementation Issues of Adaptive Energy Detection in Heterogeneous Wireless Networks

Science.gov (United States)

Sobron, Iker; Eizmendi, Iñaki; Martins, Wallace A.; Diniz, Paulo S. R.; Ordiales, Juan Luis; Velez, Manuel

2017-01-01

Spectrum sensing (SS) enables the coexistence of non-coordinated heterogeneous wireless systems operating in the same band. Due to its computational simplicity, energy detection (ED) technique has been widespread employed in SS applications; nonetheless, the conventional ED may be unreliable under environmental impairments, justifying the use of ED-based variants. Assessing ED algorithms from theoretical and simulation viewpoints relies on several assumptions and simplifications which, eventually, lead to conclusions that do not necessarily meet the requirements imposed by real propagation environments. This work addresses those problems by dealing with practical implementation issues of adaptive least mean square (LMS)-based ED algorithms. The paper proposes a new adaptive ED algorithm that uses a variable step-size guaranteeing the LMS convergence in time-varying environments. Several implementation guidelines are provided and, additionally, an empirical assessment and validation with a software defined radio-based hardware is carried out. Experimental results show good performance in terms of probabilities of detection (Pd>0.9) and false alarm (Pf∼0.05) in a range of low signal-to-noise ratios around [-4,1] dB, in both single-node and cooperative modes. The proposed sensing methodology enables a seamless monitoring of the radio electromagnetic spectrum in order to provide band occupancy information for an efficient usage among several wireless communications systems. PMID:28441751

Adaptive Decision-Making Scheme for Cognitive Radio Networks

KAUST Repository

Alqerm, Ismail

2014-05-01

Radio resource management becomes an important aspect of the current wireless networks because of spectrum scarcity and applications heterogeneity. Cognitive radio is a potential candidate for resource management because of its capability to satisfy the growing wireless demand and improve network efficiency. Decision-making is the main function of the radio resources management process as it determines the radio parameters that control the use of these resources. In this paper, we propose an adaptive decision-making scheme (ADMS) for radio resources management of different types of network applications including: power consuming, emergency, multimedia, and spectrum sharing. ADMS exploits genetic algorithm (GA) as an optimization tool for decision-making. It consists of the several objective functions for the decision-making process such as minimizing power consumption, packet error rate (PER), delay, and interference. On the other hand, maximizing throughput and spectral efficiency. Simulation results and test bed evaluation demonstrate ADMS functionality and efficiency.

Wireless Adaptive Therapeutic TeleGaming in a Pervasive Computing Environment

Science.gov (United States)

Peters, James F.; Szturm, Tony; Borkowski, Maciej; Lockery, Dan; Ramanna, Sheela; Shay, Barbara

This chapter introduces a wireless, pervasive computing approach to adaptive therapeutic telegaming considered in the context of near set theory. Near set theory provides a formal basis for observation, comparison and classification of perceptual granules. A perceptual granule is defined by a collection of objects that are graspable by the senses or by the mind. In the proposed pervasive computing approach to telegaming, a handicapped person (e.g., stroke patient with limited hand, finger, arm function) plays a video game by interacting with familiar instrumented objects such as cups, cutlery, soccer balls, nozzles, screw top-lids, spoons, so that the technology that makes therapeutic exercise game-playing possible is largely invisible (Archives of Physical Medicine and Rehabilitation 89:2213-2217, 2008). The basic approach to adaptive learning (AL) in the proposed telegaming environment is ethology-inspired and is quite different from the traditional approach to reinforcement learning. In biologically-inspired learning, organisms learn to achieve some goal by durable modification of behaviours in response to signals from the environment resulting from specific experiences (Animal Behavior, 1995). The term adaptive is used here in an ethological sense, where learning by an organism results from modifying behaviour in response to perceived changes in the environment. To instill adaptivity in a video game, it is assumed that learning by a video game is episodic. During an episode, the behaviour of a player is measured indirectly by tracking the occurrence of gaming events such as a hit or a miss of a target (e.g., hitting a moving ball with a game paddle). An ethogram provides a record of behaviour feature values that provide a basis a functional registry for handicapped players for gaming adaptivity. An important practical application of adaptive gaming is therapeutic rehabilitation exercise carried out in parallel with playing action video games. Enjoyable and

Cross-layer based adaptive wireless traffic control for per-flow and per-station fairness

Directory of Open Access Journals (Sweden)

Siwamogsatham Siwaruk

2011-01-01

Full Text Available Abstract In the IEEE 802.11 wireless LANs, the bandwidth is not fairly shared among stations due to the distributed coordination function (DCF mechanism in the IEEE 802.11 MAC protocol. It introduces the per-flow and per-station unfairness problems between uplink and downlink flows, as the uplink flows usually dominate the downlink flows. In addition, some users may use greedy applications such as video streaming, which may prevent other applications from connecting to the Internet. In this article, we propose an adaptive cross-layer bandwidth allocation mechanism to provide per-station and per-flow fairness. To verify the effectiveness and scalability, our scheme is implemented on a wireless access router and numerous experiments in a typical wireless environment with both TCP and UDP traffic are conducted to evaluate performance of the proposed scheme.

A Cluster-Based Dual-Adaptive Topology Control Approach in Wireless Sensor Networks.

Science.gov (United States)

Gui, Jinsong; Zhou, Kai; Xiong, Naixue

2016-09-25

Multi-Input Multi-Output (MIMO) can improve wireless network performance. Sensors are usually single-antenna devices due to the high hardware complexity and cost, so several sensors are used to form virtual MIMO array, which is a desirable approach to efficiently take advantage of MIMO gains. Also, in large Wireless Sensor Networks (WSNs), clustering can improve the network scalability, which is an effective topology control approach. The existing virtual MIMO-based clustering schemes do not either fully explore the benefits of MIMO or adaptively determine the clustering ranges. Also, clustering mechanism needs to be further improved to enhance the cluster structure life. In this paper, we propose an improved clustering scheme for virtual MIMO-based topology construction (ICV-MIMO), which can determine adaptively not only the inter-cluster transmission modes but also the clustering ranges. Through the rational division of cluster head function and the optimization of cluster head selection criteria and information exchange process, the ICV-MIMO scheme effectively reduces the network energy consumption and improves the lifetime of the cluster structure when compared with the existing typical virtual MIMO-based scheme. Moreover, the message overhead and time complexity are still in the same order of magnitude.

An Adaptive Channel Access Method for Dynamic Super Dense Wireless Sensor Networks.

Science.gov (United States)

Lei, Chunyang; Bie, Hongxia; Fang, Gengfa; Zhang, Xuekun

2015-12-03

Super dense and distributed wireless sensor networks have become very popular with the development of small cell technology, Internet of Things (IoT), Machine-to-Machine (M2M) communications, Vehicular-to-Vehicular (V2V) communications and public safety networks. While densely deployed wireless networks provide one of the most important and sustainable solutions to improve the accuracy of sensing and spectral efficiency, a new channel access scheme needs to be designed to solve the channel congestion problem introduced by the high dynamics of competing nodes accessing the channel simultaneously. In this paper, we firstly analyzed the channel contention problem using a novel normalized channel contention analysis model which provides information on how to tune the contention window according to the state of channel contention. We then proposed an adaptive channel contention window tuning algorithm in which the contention window tuning rate is set dynamically based on the estimated channel contention level. Simulation results show that our proposed adaptive channel access algorithm based on fast contention window tuning can achieve more than 95 % of the theoretical optimal throughput and 0 . 97 of fairness index especially in dynamic and dense networks.

An Adaptive Channel Access Method for Dynamic Super Dense Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Chunyang Lei

2015-12-01

Full Text Available Super dense and distributed wireless sensor networks have become very popular with the development of small cell technology, Internet of Things (IoT, Machine-to-Machine (M2M communications, Vehicular-to-Vehicular (V2V communications and public safety networks. While densely deployed wireless networks provide one of the most important and sustainable solutions to improve the accuracy of sensing and spectral efficiency, a new channel access scheme needs to be designed to solve the channel congestion problem introduced by the high dynamics of competing nodes accessing the channel simultaneously. In this paper, we firstly analyzed the channel contention problem using a novel normalized channel contention analysis model which provides information on how to tune the contention window according to the state of channel contention. We then proposed an adaptive channel contention window tuning algorithm in which the contention window tuning rate is set dynamically based on the estimated channel contention level. Simulation results show that our proposed adaptive channel access algorithm based on fast contention window tuning can achieve more than 95 % of the theoretical optimal throughput and 0 . 97 of fairness index especially in dynamic and dense networks.

Distortion-Based Link Adaptation for Wireless Video Transmission

Directory of Open Access Journals (Sweden)

Andrew Nix

2008-06-01

Full Text Available Wireless local area networks (WLANs such as IEEE 802.11a/g utilise numerous transmission modes, each providing different throughputs and reliability levels. Most link adaptation algorithms proposed in the literature (i maximise the error-free data throughput, (ii do not take into account the content of the data stream, and (iii rely strongly on the use of ARQ. Low-latency applications, such as real-time video transmission, do not permit large numbers of retransmission. In this paper, a novel link adaptation scheme is presented that improves the quality of service (QoS for video transmission. Rather than maximising the error-free throughput, our scheme minimises the video distortion of the received sequence. With the use of simple and local rate distortion measures and end-to-end distortion models at the video encoder, the proposed scheme estimates the received video distortion at the current transmission rate, as well as on the adjacent lower and higher rates. This allows the system to select the link-speed which offers the lowest distortion and to adapt to the channel conditions. Simulation results are presented using the MPEG-4/AVC H.264 video compression standard over IEEE 802.11g. The results show that the proposed system closely follows the optimum theoretic solution.

Reconfiguration in Mobile Multimedia Systems

NARCIS (Netherlands)

Smit, Gerardus Johannes Maria; Havinga, Paul J.M.; Bos, M.; Smit, L.T.; Heysters, P.M.

2000-01-01

Dynamically reconfigurable systems offer the potential for realising efficient systems as well as providing adaptability to changing system requirements. Such systems are suitable for future mobile multimedia systems that have limited battery resources, must handle diverse data types, and must

Streaming Multimedia via Overlay Networks using Wi-Fi Peer-to-Peer Connections

DEFF Research Database (Denmark)

Poderys, Justas; Soler, José

2017-01-01

Short range ad-hoc wireless networks can be used to deliver streaming multimedia for information, entertainment and advertisement purposes. To enable short-range communication between various devices, the Wi-Fi Alliance proposed an extension to the IEEE802.11 Wi-Fi standard called Wi-Fi Peer......-to-Peer (P2P). It allows compliant devices to form ad-hoc communication groups without interrupting conventional access point-based Wi-Fi communication. This paper proposes to use Wi-Fi P2P connectivity to distribute streaming multimedia in ah-hoc formed user groups. The exchange of multimedia data...... is performed by forming an overlay network using Peer-to-Peer Streaming Peer Protocol (PPSPP). In order to make PPSPP function over WiFi P2P connections, this paper proposes a number of changes to the protocol. The performance of the proposed system is evaluated using a computer networks emulator...

Adaptive Naive Bayes classification for wireless sensor networks

NARCIS (Netherlands)

Zwartjes, G.J.

2017-01-01

Wireless Sensor Networks are tiny devices equipped with sensors and wireless communication. These devices observe environments and communicatie about these observations. Machine Learning techniques are of interest for Wireless Sensor Network applications since they can reduce the amount of needed

Control Strategy for Vehicle Inductive Wireless Charging Based on Load Adaptive and Frequency Adjustment

Directory of Open Access Journals (Sweden)

Shichun Yang

2018-05-01

Full Text Available Wireless charging system for electric vehicles is a hot research issue in the world today. Since the existing research on wireless charging is mostly forward-looking aimed at low-power appliances like household appliances, while electric vehicles need a high-power, high-efficiency, and strong coupling wireless charging system. In this paper, we have specifically designed a 6.6 KW wireless charging system for electric vehicles and have proposed a control strategy suitable for electric vehicles according to its power charging characteristics and existing common wired charging protocol. Firstly, the influence of the equivalent load and frequency bifurcation on a wireless charging system is analyzed in this paper. Secondly, an adaptive load control strategy matching the characteristics of the battery, and the charging pile is put forward to meet the constant current and constant voltage charging requirements to improve the system efficiency. In addition, the frequency adjustment control strategy is designed to realize the real-time dynamic optimization of the entire system. It utilizes the improved methods of rapid judgment, variable step length matching and frequency splitting recognition, which are not adopted in early related researches. Finally, the results of 6.6 kW test show that the control strategy works perfectly since system response time can be reduced to less than 1 s, and the overall efficiency of the wireless charging system and the grid power supply module can reach up to 91%.

A Priority-Based Adaptive MAC Protocol for Wireless Body Area Networks

Directory of Open Access Journals (Sweden)

Sabin Bhandari

2016-03-01

Full Text Available In wireless body area networks (WBANs, various sensors and actuators are placed on/inside the human body and connected wirelessly. WBANs have specific requirements for healthcare and medical applications, hence, standard protocols like the IEEE 802.15.4 cannot fulfill all the requirements. Consequently, many medium access control (MAC protocols, mostly derived from the IEEE 802.15.4 superframe structure, have been studied. Nevertheless, they do not support a differentiated quality of service (QoS for the various forms of traffic coexisting in a WBAN. In particular, a QoS-aware MAC protocol is essential for WBANs operating in the unlicensed Industrial, Scientific, and Medical (ISM bands, because different wireless services like Bluetooth, WiFi, and Zigbee may coexist there and cause severe interference. In this paper, we propose a priority-based adaptive MAC (PA-MAC protocol for WBANs in unlicensed bands, which allocates time slots dynamically, based on the traffic priority. Further, multiple channels are effectively utilized to reduce access delays in a WBAN, in the presence of coexisting systems. Our performance evaluation results show that the proposed PA-MAC outperforms the IEEE 802.15.4 MAC and the conventional priority-based MAC in terms of the average transmission time, throughput, energy consumption, and data collision ratio.

A Priority-Based Adaptive MAC Protocol for Wireless Body Area Networks.

Science.gov (United States)

Bhandari, Sabin; Moh, Sangman

2016-03-18

In wireless body area networks (WBANs), various sensors and actuators are placed on/inside the human body and connected wirelessly. WBANs have specific requirements for healthcare and medical applications, hence, standard protocols like the IEEE 802.15.4 cannot fulfill all the requirements. Consequently, many medium access control (MAC) protocols, mostly derived from the IEEE 802.15.4 superframe structure, have been studied. Nevertheless, they do not support a differentiated quality of service (QoS) for the various forms of traffic coexisting in a WBAN. In particular, a QoS-aware MAC protocol is essential for WBANs operating in the unlicensed Industrial, Scientific, and Medical (ISM) bands, because different wireless services like Bluetooth, WiFi, and Zigbee may coexist there and cause severe interference. In this paper, we propose a priority-based adaptive MAC (PA-MAC) protocol for WBANs in unlicensed bands, which allocates time slots dynamically, based on the traffic priority. Further, multiple channels are effectively utilized to reduce access delays in a WBAN, in the presence of coexisting systems. Our performance evaluation results show that the proposed PA-MAC outperforms the IEEE 802.15.4 MAC and the conventional priority-based MAC in terms of the average transmission time, throughput, energy consumption, and data collision ratio.

A wirelessly powered electro-acupuncture based on adaptive pulsewidth monophase stimulation.

Science.gov (United States)

Kiseok Song; Long Yan; Seulki Lee; Yoo, Jerald; Hoi-Jun Yoo

2011-04-01

A wirelessly powered electro-acupuncture (EA) system with adaptive-pulsewidth (APW) monophase stimulation is presented for convenient invasive medicine. The proposed system removes cumbersome wires connected between EA nodes and an EA controller in order to realize both patients' convenience and remedial values simultaneously. An ultra-low-power stimulator integrated circuit (IC) that is integrated on the flexible-printed-circuit board (F-PCB) is attached to the tip of a needle electrode. Combined with a conductive yarn helical antenna wound around the needle electrode, the EA node receives wireless power from the EA controller using 433 MHz with the maximum loss of 6 dB. A zero-Vth nMOS rectifier harvests a supply voltage of 1.0 V from a -16-dBm incoming power signal with 32% efficiency. To deal with a body impedance variation (BIV) in the range of 100-200 kΩ , the proposed APW stimulator IC, fabricated in a 0.18-μm 1P6M complementary metal-oxide semiconductor CMOS process and occupying 1.56 mm(2), enables constant charge injection of 80-nC/stimulation. To ensure the patients' safety, the EA node (a pair of EAs) shares ground and clock wires to operate in alternate monophase (AMP) fashion for neutralizing the injected charge. The proposed wirelessly powered EA node was verified by applying it to a chunk of pork as a body model with the wireless power supplied from an RF signal generator (output power of 10 dBm and located 30 cm away).

Adapting Mobile Beacon-Assisted Localization in Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Wei Dong

2009-04-01

Full Text Available The ability to automatically locate sensor nodes is essential in many Wireless Sensor Network (WSN applications. To reduce the number of beacons, many mobile-assisted approaches have been proposed. Current mobile-assisted approaches for localization require special hardware or belong to centralized localization algorithms involving some deterministic approaches due to the fact that they explicitly consider the impreciseness of location estimates. In this paper, we first propose a range-free, distributed and probabilistic Mobile Beacon-assisted Localization (MBL approach for static WSNs. Then, we propose another approach based on MBL, called Adapting MBL (A-MBL, to increase the efficiency and accuracy of MBL by adapting the size of sample sets and the parameter of the dynamic model during the estimation process. Evaluation results show that the accuracy of MBL and A-MBL outperform both Mobile and Static sensor network Localization (MSL and Arrival and Departure Overlap (ADO when both of them use only a single mobile beacon for localization in static WSNs.

Adapting mobile beacon-assisted localization in wireless sensor networks.

Science.gov (United States)

Teng, Guodong; Zheng, Kougen; Dong, Wei

2009-01-01

The ability to automatically locate sensor nodes is essential in many Wireless Sensor Network (WSN) applications. To reduce the number of beacons, many mobile-assisted approaches have been proposed. Current mobile-assisted approaches for localization require special hardware or belong to centralized localization algorithms involving some deterministic approaches due to the fact that they explicitly consider the impreciseness of location estimates. In this paper, we first propose a range-free, distributed and probabilistic Mobile Beacon-assisted Localization (MBL) approach for static WSNs. Then, we propose another approach based on MBL, called Adapting MBL (A-MBL), to increase the efficiency and accuracy of MBL by adapting the size of sample sets and the parameter of the dynamic model during the estimation process. Evaluation results show that the accuracy of MBL and A-MBL outperform both Mobile and Static sensor network Localization (MSL) and Arrival and Departure Overlap (ADO) when both of them use only a single mobile beacon for localization in static WSNs.

Reading Games: Close Viewing and Guided Playing of Multimedia Texts

Science.gov (United States)

Kozdras, Deborah; Joseph, Christine; Schneider, Jenifer Jasinski

2015-01-01

In this article, we describe how literacy strategies can be adapted for playing (and reading) video games--games that embed disciplinary content in multimedia texts. Using close viewing and guided playing strategies with online games and simulations, we share ideas for helping students navigate and comprehend multimedia texts in order to learn…

Supporting Dynamic Adaptive Streaming over HTTP in Wireless Meshed Networks using Random Linear Network Coding

DEFF Research Database (Denmark)

Hundebøll, Martin; Pedersen, Morten Videbæk; Roetter, Daniel Enrique Lucani

2014-01-01

This work studies the potential and impact of the FRANC network coding protocol for delivering high quality Dynamic Adaptive Streaming over HTTP (DASH) in wireless networks. Although DASH aims to tailor the video quality rate based on the available throughput to the destination, it relies...

A Cluster-Based Dual-Adaptive Topology Control Approach in Wireless Sensor Networks

Science.gov (United States)

Gui, Jinsong; Zhou, Kai; Xiong, Naixue

2016-01-01

Multi-Input Multi-Output (MIMO) can improve wireless network performance. Sensors are usually single-antenna devices due to the high hardware complexity and cost, so several sensors are used to form virtual MIMO array, which is a desirable approach to efficiently take advantage of MIMO gains. Also, in large Wireless Sensor Networks (WSNs), clustering can improve the network scalability, which is an effective topology control approach. The existing virtual MIMO-based clustering schemes do not either fully explore the benefits of MIMO or adaptively determine the clustering ranges. Also, clustering mechanism needs to be further improved to enhance the cluster structure life. In this paper, we propose an improved clustering scheme for virtual MIMO-based topology construction (ICV-MIMO), which can determine adaptively not only the inter-cluster transmission modes but also the clustering ranges. Through the rational division of cluster head function and the optimization of cluster head selection criteria and information exchange process, the ICV-MIMO scheme effectively reduces the network energy consumption and improves the lifetime of the cluster structure when compared with the existing typical virtual MIMO-based scheme. Moreover, the message overhead and time complexity are still in the same order of magnitude. PMID:27681731

A Cluster-Based Dual-Adaptive Topology Control Approach in Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Jinsong Gui

2016-09-01

Full Text Available Multi-Input Multi-Output (MIMO can improve wireless network performance. Sensors are usually single-antenna devices due to the high hardware complexity and cost, so several sensors are used to form virtual MIMO array, which is a desirable approach to efficiently take advantage of MIMO gains. Also, in large Wireless Sensor Networks (WSNs, clustering can improve the network scalability, which is an effective topology control approach. The existing virtual MIMO-based clustering schemes do not either fully explore the benefits of MIMO or adaptively determine the clustering ranges. Also, clustering mechanism needs to be further improved to enhance the cluster structure life. In this paper, we propose an improved clustering scheme for virtual MIMO-based topology construction (ICV-MIMO, which can determine adaptively not only the inter-cluster transmission modes but also the clustering ranges. Through the rational division of cluster head function and the optimization of cluster head selection criteria and information exchange process, the ICV-MIMO scheme effectively reduces the network energy consumption and improves the lifetime of the cluster structure when compared with the existing typical virtual MIMO-based scheme. Moreover, the message overhead and time complexity are still in the same order of magnitude.

A Survey on Multimedia-Based Cross-Layer Optimization in Visual Sensor Networks

Science.gov (United States)

Costa, Daniel G.; Guedes, Luiz Affonso

2011-01-01

Visual sensor networks (VSNs) comprised of battery-operated electronic devices endowed with low-resolution cameras have expanded the applicability of a series of monitoring applications. Those types of sensors are interconnected by ad hoc error-prone wireless links, imposing stringent restrictions on available bandwidth, end-to-end delay and packet error rates. In such context, multimedia coding is required for data compression and error-resilience, also ensuring energy preservation over the path(s) toward the sink and improving the end-to-end perceptual quality of the received media. Cross-layer optimization may enhance the expected efficiency of VSNs applications, disrupting the conventional information flow of the protocol layers. When the inner characteristics of the multimedia coding techniques are exploited by cross-layer protocols and architectures, higher efficiency may be obtained in visual sensor networks. This paper surveys recent research on multimedia-based cross-layer optimization, presenting the proposed strategies and mechanisms for transmission rate adjustment, congestion control, multipath selection, energy preservation and error recovery. We note that many multimedia-based cross-layer optimization solutions have been proposed in recent years, each one bringing a wealth of contributions to visual sensor networks. PMID:22163908

Source Coding for Wireless Distributed Microphones in Reverberant Environments

DEFF Research Database (Denmark)

Zahedi, Adel

2016-01-01

. However, it comes with the price of several challenges, including the limited power and bandwidth resources for wireless transmission of audio recordings. In such a setup, we study the problem of source coding for the compression of the audio recordings before the transmission in order to reduce the power...... consumption and/or transmission bandwidth by reduction in the transmission rates. Source coding for wireless microphones in reverberant environments has several special characteristics which make it more challenging in comparison with regular audio coding. The signals which are acquired by the microphones......Modern multimedia systems are more and more shifting toward distributed and networked structures. This includes audio systems, where networks of wireless distributed microphones are replacing the traditional microphone arrays. This allows for flexibility of placement and high spatial diversity...

An FEC Adaptive Multicast MAC Protocol for Providing Reliability in WLANs

Science.gov (United States)

Basalamah, Anas; Sato, Takuro

For wireless multicast applications like multimedia conferencing, voice over IP and video/audio streaming, a reliable transmission of packets within short delivery delay is needed. Moreover, reliability is crucial to the performance of error intolerant applications like file transfer, distributed computing, chat and whiteboard sharing. Forward Error Correction (FEC) is frequently used in wireless multicast to enhance Packet Error Rate (PER) performance, but cannot assure full reliability unless coupled with Automatic Repeat Request forming what is knows as Hybrid-ARQ. While reliable FEC can be deployed at different levels of the protocol stack, it cannot be deployed on the MAC layer of the unreliable IEEE802.11 WLAN due to its inability to exchange ACKs with multiple recipients. In this paper, we propose a Multicast MAC protocol that enhances WLAN reliability by using Adaptive FEC and study it's performance through mathematical analysis and simulation. Our results show that our protocol can deliver high reliability and throughput performance.

L2-LBMT: A Layered Load Balance Routing Protocol for underwater multimedia data transmission

Science.gov (United States)

Lv, Ze; Tang, Ruichun; Tao, Ye; Sun, Xin; Xu, Xiaowei

2017-12-01

Providing highly efficient underwater transmission of mass multimedia data is challenging due to the particularities of the underwater environment. Although there are many schemes proposed to optimize the underwater acoustic network communication protocols, from physical layer, data link layer, network layer to transport layer, the existing routing protocols for underwater wireless sensor network (UWSN) still cannot well deal with the problems in transmitting multimedia data because of the difficulties involved in high energy consumption, low transmission reliability or high transmission delay. It prevents us from applying underwater multimedia data to real-time monitoring of marine environment in practical application, especially in emergency search, rescue operation and military field. Therefore, the inefficient transmission of marine multimedia data has become a serious problem that needs to be solved urgently. In this paper, A Layered Load Balance Routing Protocol (L2-LBMT) is proposed for underwater multimedia data transmission. In L2-LBMT, we use layered and load-balance Ad Hoc Network to transmit data, and adopt segmented data reliable transfer (SDRT) protocol to improve the data transport reliability. And a 3-node variant of tornado (3-VT) code is also combined with the Ad Hoc Network to transmit little emergency data more quickly. The simulation results show that the proposed protocol can balance energy consumption of each node, effectively prolong the network lifetime and reduce transmission delay of marine multimedia data.

MIMO Based Multimedia Communication System

OpenAIRE

Kandar, D.; Dhar, Sourav; Bera, Rabindranath; Sarkar, C. K.

2009-01-01

High data rate is required for multimedia communication. But the communication at high data rate is always challenging. In this work we have successfully performed data chatting, Voice chatting and high quality video transmission between two distant units using MIMO adapter, Direct sequence spread spectrum system and MATLAB/SIMULINK platform.

Adaptive Security in ODMAC for Multihop Energy Harvesting Wireless Sensor Networks

DEFF Research Database (Denmark)

Di Mauro, Alessio; Fafoutis, Xenofon; Dragoni, Nicola

2015-01-01

Energy Harvesting Wireless Sensor Networks (EH-WSNs) represent an interesting new paradigm where individual nodes forming a network are powered by energy sources scavenged from the surrounding environment. This technique provides numerous advantages, but also new design challenges. Securing...... the communications under energy constraints represents one of these key challenges. The amount of energy available is theoretically infinite in the long run but highly variable over short periods of time, and managing it is a crucial aspect. In this paper we present an adaptive approach for security in multihop EH...

The Legal Nature of Video Games – Adapting Copyright Law to Multimedia

Directory of Open Access Journals (Sweden)

Julian Simon Stein

2015-06-01

Full Text Available In Copyright Law, video games are still a contentious matter. The multimedia nature of games brings up the question on how to define their legal nature. While there are several original underlying works in video games such as computer programs, artistic works, musical works, dramatic works etc., video games enjoy protection as films or audiovisual works respectively in many jurisdictions, making video games an arrangement of a multiplicity of works. However, some have argued to define video games as a single 'multimedia work' rather than a product of many works of copyright.This article analyses the different types of original and derivative works contained in video games before evaluating the necessity and feasibility of a multimedia category of work, arguing in favour of the current system.

Space-Time Equalization for High-Speed Wireless Digital Communications Based on Multipath-Incorporating Matched Filtering, Zero Forcing Equalization, and MMSE

National Research Council Canada - National Science Library

Zoltowski, Michael D

2003-01-01

The project has successfully demonstrated reduced-rank, space-time equalization for high-speed wireless digital communications capable of reliably transmitting multimedia data in support of military...

An Efficient and Self-Adapting Localization in Static Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Wei Dong

2009-08-01

Full Text Available Localization is one of the most important subjects in Wireless Sensor Networks (WSNs. To reduce the number of beacons and adopt probabilistic methods, some particle filter-based mobile beacon-assisted localization approaches have been proposed, such as Mobile Beacon-assisted Localization (MBL, Adapting MBL (A-MBL, and the method proposed by Hang et al. Some new significant problems arise in these approaches, however. The first question is which probability distribution should be selected as the dynamic model in the prediction stage. The second is whether the unknown node adopts neighbors’ observation in the update stage. The third is how to find a self-adapting mechanism to achieve more flexibility in the adapting stage. In this paper, we give the theoretical analysis and experimental evaluations to suggest which probability distribution in the dynamic model should be adopted to improve the efficiency in the prediction stage. We also give the condition for whether the unknown node should use the observations from its neighbors to improve the accuracy. Finally, we propose a Self-Adapting Mobile Beacon-assisted Localization (SA-MBL approach to achieve more flexibility and achieve almost the same performance with A-MBL.

Adaptive Step Size Gradient Ascent ICA Algorithm for Wireless MIMO Systems

Directory of Open Access Journals (Sweden)

Zahoor Uddin

2018-01-01

Full Text Available Independent component analysis (ICA is a technique of blind source separation (BSS used for separation of the mixed received signals. ICA algorithms are classified into adaptive and batch algorithms. Adaptive algorithms perform well in time-varying scenario with high-computational complexity, while batch algorithms have better separation performance in quasistatic channels with low-computational complexity. Amongst batch algorithms, the gradient-based ICA algorithms perform well, but step size selection is critical in these algorithms. In this paper, an adaptive step size gradient ascent ICA (ASS-GAICA algorithm is presented. The proposed algorithm is free from selection of the step size parameter with improved convergence and separation performance. Different performance evaluation criteria are used to verify the effectiveness of the proposed algorithm. Performance of the proposed algorithm is compared with the FastICA and optimum block adaptive ICA (OBAICA algorithms for quasistatic and time-varying wireless channels. Simulation is performed over quadrature amplitude modulation (QAM and binary phase shift keying (BPSK signals. Results show that the proposed algorithm outperforms the FastICA and OBAICA algorithms for a wide range of signal-to-noise ratio (SNR and input data block lengths.

Efficient and Adaptive Node Selection for Target Tracking in Wireless Sensor Network

Directory of Open Access Journals (Sweden)

Juan Feng

2016-01-01

Full Text Available In target tracking wireless sensor network, choosing the proper working nodes can not only minimize the number of active nodes, but also satisfy the tracking reliability requirement. However, most existing works focus on selecting sensor nodes which are the nearest to the target for tracking missions and they did not consider the correlation of the location of the sensor nodes so that these approaches can not meet all the goals of the network. This work proposes an efficient and adaptive node selection approach for tracking a target in a distributed wireless sensor network. The proposed approach combines the distance-based node selection strategy and particle filter prediction considering the spatial correlation of the different sensing nodes. Moreover, a joint distance weighted measurement is proposed to estimate the information utility of sensing nodes. Experimental results show that EANS outperformed the state-of-the-art approaches by reducing the energy cost and computational complexity as well as guaranteeing the tracking accuracy.

A Hybrid Adaptive Routing Algorithm for Event-Driven Wireless Sensor Networks

Science.gov (United States)

Figueiredo, Carlos M. S.; Nakamura, Eduardo F.; Loureiro, Antonio A. F.

2009-01-01

Routing is a basic function in wireless sensor networks (WSNs). For these networks, routing algorithms depend on the characteristics of the applications and, consequently, there is no self-contained algorithm suitable for every case. In some scenarios, the network behavior (traffic load) may vary a lot, such as an event-driven application, favoring different algorithms at different instants. This work presents a hybrid and adaptive algorithm for routing in WSNs, called Multi-MAF, that adapts its behavior autonomously in response to the variation of network conditions. In particular, the proposed algorithm applies both reactive and proactive strategies for routing infrastructure creation, and uses an event-detection estimation model to change between the strategies and save energy. To show the advantages of the proposed approach, it is evaluated through simulations. Comparisons with independent reactive and proactive algorithms show improvements on energy consumption. PMID:22423207

A Complexity-Aware Video Adaptation Mechanism for Live Streaming Systems

Directory of Open Access Journals (Sweden)

Chen Homer H

2007-01-01

Full Text Available The paradigm shift of network design from performance-centric to constraint-centric has called for new signal processing techniques to deal with various aspects of resource-constrained communication and networking. In this paper, we consider the computational constraints of a multimedia communication system and propose a video adaptation mechanism for live video streaming of multiple channels. The video adaptation mechanism includes three salient features. First, it adjusts the computational resource of the streaming server block by block to provide a fine control of the encoding complexity. Second, as far as we know, it is the first mechanism to allocate the computational resource to multiple channels. Third, it utilizes a complexity-distortion model to determine the optimal coding parameter values to achieve global optimization. These techniques constitute the basic building blocks for a successful application of wireless and Internet video to digital home, surveillance, IPTV, and online games.

A Complexity-Aware Video Adaptation Mechanism for Live Streaming Systems

Science.gov (United States)

Lu, Meng-Ting; Yao, Jason J.; Chen, Homer H.

2007-12-01

The paradigm shift of network design from performance-centric to constraint-centric has called for new signal processing techniques to deal with various aspects of resource-constrained communication and networking. In this paper, we consider the computational constraints of a multimedia communication system and propose a video adaptation mechanism for live video streaming of multiple channels. The video adaptation mechanism includes three salient features. First, it adjusts the computational resource of the streaming server block by block to provide a fine control of the encoding complexity. Second, as far as we know, it is the first mechanism to allocate the computational resource to multiple channels. Third, it utilizes a complexity-distortion model to determine the optimal coding parameter values to achieve global optimization. These techniques constitute the basic building blocks for a successful application of wireless and Internet video to digital home, surveillance, IPTV, and online games.

Wireless adiabatic power transfer

International Nuclear Information System (INIS)

Rangelov, A.A.; Suchowski, H.; Silberberg, Y.; Vitanov, N.V.

2011-01-01

Research highlights: → Efficient and robust mid-range wireless energy transfer between two coils. → The adiabatic energy transfer is analogous to adiabatic passage in quantum optics. → Wireless energy transfer is insensitive to any resonant constraints. → Wireless energy transfer is insensitive to noise in the neighborhood of the coils. - Abstract: We propose a technique for efficient mid-range wireless power transfer between two coils, by adapting the process of adiabatic passage for a coherently driven two-state quantum system to the realm of wireless energy transfer. The proposed technique is shown to be robust to noise, resonant constraints, and other interferences that exist in the neighborhood of the coils.

Underwater wireless optical MIMO system with spatial modulation and adaptive power allocation

Science.gov (United States)

Huang, Aiping; Tao, Linwei; Niu, Yilong

2018-04-01

In this paper, we investigate the performance of underwater wireless optical multiple-input multiple-output communication system combining spatial modulation (SM-UOMIMO) with flag dual amplitude pulse position modulation (FDAPPM). Channel impulse response for coastal and harbor ocean water links are obtained by Monte Carlo (MC) simulation. Moreover, we obtain the closed-form and upper bound average bit error rate (BER) expressions for receiver diversity including optical combining, equal gain combining and selected combining. And a novel adaptive power allocation algorithm (PAA) is proposed to minimize the average BER of SM-UOMIMO system. Our numeric results indicate an excellent match between the analytical results and numerical simulations, which confirms the accuracy of our derived expressions. Furthermore, the results show that adaptive PAA outperforms conventional fixed factor PAA and equal PAA obviously. Multiple-input single-output system with adaptive PAA obtains even better BER performance than MIMO one, at the same time reducing receiver complexity effectively.

Multimedia

Science.gov (United States)

Kaye, Karen

1993-01-01

Multimedia initiative objectives for the NASA Scientific and Technical Information (STI) program are described. A multimedia classification scheme was developed and the types of non-print media currently in use are inventoried. The NASA STI Program multimedia initiative is driven by a changing user population and technical requirements in the areas of publications, dissemination, and user and management support.

Multi-Channel Multi-Radio Using 802.11 Based Media Access for Sink Nodes in Wireless Sensor Networks

OpenAIRE

Campbell, Carlene E.-A.; Khan, Shafiullah; Singh, Dhananjay; Loo, Kok-Keong

2011-01-01

The next generation surveillance and multimedia systems will become increasingly deployed as wireless sensor networks in order to monitor parks, public places and for business usage. The convergence of data and telecommunication over IP-based networks has paved the way for wireless networks. Functions are becoming more intertwined by the compelling force of innovation and technology. For example, many closed-circuit TV premises surveillance systems now rely on transmitting their images and da...

11th International Conference on Multimedia and Ubiquitous Engineering & 12th International Conference on Future Information Technology

CERN Document Server

Chen, Shu-Ching; Choo, Kim-Kwang

2017-01-01

This book presents the proceedings of the 11th International Conference on Multimedia and Ubiquitous Engineering (MUE2017) and the 12th International Conference on Future Information Technology (FutureTech2017), held in Seoul, South Korea on May 22–24, 2017. These two conferences provided an opportunity for academic and industrial professionals to discuss recent advances in the area of multimedia and ubiquitous environments including models and systems, new directions, and novel applications associated with the utilization and acceptance of ubiquitous computing devices and systems. The resulting papers address the latest technological innovations in the fields of digital convergence, multimedia convergence, intelligent applications, embedded systems, mobile and wireless communications, bio-inspired computing, grid and cloud computing, semantic web, user experience, HCI, and security and trust computing. The book offers a valuable resource for a broad readership, including students, academic researchers, and...

Wireless application guidelines for usability design and evaluation for developing countries

International Nuclear Information System (INIS)

Khoja, S.A.; Ursani, A.A.; Ali, A.

2009-01-01

The aim of this paper is to provide guidelines for designing wireless applications. These guidelines are developed with the help of Human Computer Interaction based Usability Evaluation surveys and tests results. These guidelines will help in making wireless applications more usable and attractive for users and will help designers to plan effective interactive applications. The guidelines presented in the paper have been derived from the results of surveys, usability tests and SET (Summative Evaluation Tests) carried out over 200 people of Karachi, Pakistan, from different walks of life with different academic and professional backgrounds, making imperative suggestions not only to improve the usability of exciting features given in wireless and mobile products, but also provide suggestions to improve usability of basic components such as, text, navigation, interactivity, multimedia, control and behavior. (author)

Adaptive Probabilistic Broadcasting over Dense Wireless Ad Hoc Networks

Directory of Open Access Journals (Sweden)

Victor Gau

2010-01-01

Full Text Available We propose an idle probability-based broadcasting method, iPro, which employs an adaptive probabilistic mechanism to improve performance of data broadcasting over dense wireless ad hoc networks. In multisource one-hop broadcast scenarios, the modeling and simulation results of the proposed iPro are shown to significantly outperform the standard IEEE 802.11 under saturated condition. Moreover, the results also show that without estimating the number of competing nodes and changing the contention window size, the performance of the proposed iPro can still approach the theoretical bound. We further apply iPro to multihop broadcasting scenarios, and the experiment results show that within the same elapsed time after the broadcasting, the proposed iPro has significantly higher Packet-Delivery Ratios (PDR than traditional methods.

An Adaptive Handover Prediction Scheme for Seamless Mobility Based Wireless Networks

Directory of Open Access Journals (Sweden)

Ali Safa Sadiq

2014-01-01

Full Text Available We propose an adaptive handover prediction (AHP scheme for seamless mobility based wireless networks. That is, the AHP scheme incorporates fuzzy logic with AP prediction process in order to lend cognitive capability to handover decision making. Selection metrics, including received signal strength, mobile node relative direction towards the access points in the vicinity, and access point load, are collected and considered inputs of the fuzzy decision making system in order to select the best preferable AP around WLANs. The obtained handover decision which is based on the calculated quality cost using fuzzy inference system is also based on adaptable coefficients instead of fixed coefficients. In other words, the mean and the standard deviation of the normalized network prediction metrics of fuzzy inference system, which are collected from available WLANs are obtained adaptively. Accordingly, they are applied as statistical information to adjust or adapt the coefficients of membership functions. In addition, we propose an adjustable weight vector concept for input metrics in order to cope with the continuous, unpredictable variation in their membership degrees. Furthermore, handover decisions are performed in each MN independently after knowing RSS, direction toward APs, and AP load. Finally, performance evaluation of the proposed scheme shows its superiority compared with representatives of the prediction approaches.

Psychological and Pedagogical Foundations of Multimedia Technologies Application for School Use

Directory of Open Access Journals (Sweden)

Larisa A. Shkutina

2013-01-01

Full Text Available The article deals with the topical problem of psychological and pedagogical basis development for the use of new information technologies at university and at school. Features of the use of multimedia technologies were studied, basing on the analysis of scientific works. Multimedia technologies have a number of advantages and possibilities to influence psychological environment of students and the internal processes of educational information processing by the human brain. The advisability of the use of multimedia technologies, enabling to apply all kinds of information, affecting the sensor channels, and summing up in a single image is proved. High didactic possibilities of multimedia technologies, contributing to the performance of cognitive, creative, informational, social, adaptive and other needs of students are revealed.

15 Gbit/s indoor optical wireless systems employing fast adaptation and imaging reception in a realistic environment

Science.gov (United States)

Alsaadi, Fuad E.

2016-03-01

Optical wireless systems are promising candidates for next-generation indoor communication networks. Optical wireless technology offers freedom from spectrum regulations and, compared to current radio-frequency networks, higher data rates and increased security. This paper presents a fast adaptation method for multibeam angle and delay adaptation systems and a new spot-diffusing geometry, and also considers restrictions needed for complying with eye safety regulations. The fast adaptation algorithm reduces the computational load required to reconfigure the transmitter in the case of transmitter and/or receiver mobility. The beam clustering approach enables the transmitter to assign power to spots within the pixel's field of view (FOV) and increases the number of such spots. Thus, if the power per spot is restricted to comply with eye safety standards, the new approach, in which more spots are visible within the FOV of the pixel, leads to enhanced signal-to-noise ratio (SNR). Simulation results demonstrate that the techniques proposed in this paper lead to SNR improvements that enable reliable operation at data rates as high as 15 Gbit/s. These results are based on simulation and not on actual measurements or experiments.

Adaptive Protocols for Mobile Wireless Networks

National Research Council Canada - National Science Library

Pursley, Michael B

2005-01-01

Results are reported for basic research in mobile wireless communication networks for tactical applications including investigations of new methods for error-control coding and decoding, modulation...

Enhancing Cognitive Theory of Multimedia Leaning through 3D Animation

Directory of Open Access Journals (Sweden)

Zeeshan Bhatti

2017-12-01

Full Text Available Cognitive theory of Multimedia learning has been a widely used principle in education. However, with current technological advancements and usage, the teaching and learning trend of children’s have also changed with more dependability towards technology. This research work explores and implement the use of 3D Animation as tool for multimedia learning based on cognitive theory. This new dimension in cognitive learning, will foster the latest multimedia tools and application driven through 3D Animation, Virtual Reality and Augmented Reality. The three principles, that facilitate cognitive theory of multimedia learning using animation, addressed in this research are temporal contiguity principle (screening matching narration with animation simultaneously rather than successively, personalization principle (screening text or dialogs in casual form rather than formal style and finally the multimedia principle (screen animation and audio narration together instead of just narration. The result of this new model would yield a new technique of educating the young children through 3D animation and virtual reality. The adaptation of  cognitive theory through 3D animation as a source of multimedia learning with various key principles produces a reliable paradigm for educational enhancement.

Smart Antennas for Battlefield Multimedia Wireless Networks with Dual Use Applications

National Research Council Canada - National Science Library

Paulraj, Arogyaswami

1998-01-01

Work under this contract focused on algorithms for space time processing (STP) address the critical needs of the wireless battlefield network including high speed data, enhanced coverage and capacity, low power, and antijam capability...

Adaptive Energy-Efficient Target Detection Based on Mobile Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Tengyue Zou

2017-05-01

Full Text Available Target detection is a widely used application for area surveillance, elder care, and fire alarms; its purpose is to find a particular object or event in a region of interest. Usually, fixed observing stations or static sensor nodes are arranged uniformly in the field. However, each part of the field has a different probability of being intruded upon; if an object suddenly enters an area with few guardian devices, a loss of detection will occur, and the stations in the safe areas will waste their energy for a long time without any discovery. Thus, mobile wireless sensor networks may benefit from adaptation and pertinence in detection. Sensor nodes equipped with wheels are able to move towards the risk area via an adaptive learning procedure based on Bayesian networks. Furthermore, a clustering algorithm based on k-means++ and an energy control mechanism is used to reduce the energy consumption of nodes. The extended Kalman filter and a voting data fusion method are employed to raise the localization accuracy of the target. The simulation and experimental results indicate that this new system with adaptive energy-efficient methods is able to achieve better performance than the traditional ones.

Adaptive Energy-Efficient Target Detection Based on Mobile Wireless Sensor Networks.

Science.gov (United States)

Zou, Tengyue; Li, Zhenjia; Li, Shuyuan; Lin, Shouying

2017-05-04

Target detection is a widely used application for area surveillance, elder care, and fire alarms; its purpose is to find a particular object or event in a region of interest. Usually, fixed observing stations or static sensor nodes are arranged uniformly in the field. However, each part of the field has a different probability of being intruded upon; if an object suddenly enters an area with few guardian devices, a loss of detection will occur, and the stations in the safe areas will waste their energy for a long time without any discovery. Thus, mobile wireless sensor networks may benefit from adaptation and pertinence in detection. Sensor nodes equipped with wheels are able to move towards the risk area via an adaptive learning procedure based on Bayesian networks. Furthermore, a clustering algorithm based on k -means++ and an energy control mechanism is used to reduce the energy consumption of nodes. The extended Kalman filter and a voting data fusion method are employed to raise the localization accuracy of the target. The simulation and experimental results indicate that this new system with adaptive energy-efficient methods is able to achieve better performance than the traditional ones.

Wi-Fi Walkman : A wireless handhold that shares and recommends music on peer-to-peer networks

NARCIS (Netherlands)

Wang, J.; Reinders, M.J.T.; Pouwelse, J.; Lagendijk, R.L.

2005-01-01

The Wi-Fi walkman is a mobile multimedia application that we developed to investigate the technological and usability aspects of human-computer interaction with personalized, intelligent and context-aware wearable devices in peer-to-peer wireless environments such as the future home, office, or

The Effects of Multimedia and Learning Style on Student Achievement in Online Electronics Course

Science.gov (United States)

Surjono, Herman Dwi

2015-01-01

This experimental study investigated the effects of multimedia preferences and learning styles on undergraduate student achievement in an adaptive e-learning system for electronics course at the Yogyakarta State University Indonesia. The findings showed that students in which their multimedia preferences and learning style matched with the way the…

Semantic Multimedia

NARCIS (Netherlands)

S. Staab; A. Scherp; R. Arndt; R. Troncy (Raphael); M. Grzegorzek; C. Saathoff; S. Schenk; L. Hardman (Lynda)

2008-01-01

htmlabstractMultimedia constitutes an interesting field of application for Semantic Web and Semantic Web reasoning, as the access and management of multimedia content and context depends strongly on the semantic descriptions of both. At the same time, multimedia resources constitute complex objects,

An IMS-Based Middleware Solution for Energy-Efficient and Cost-Effective Mobile Multimedia Services

Science.gov (United States)

Bellavista, Paolo; Corradi, Antonio; Foschini, Luca

Mobile multimedia services have recently become of extreme industrial relevance due to the advances in both wireless client devices and multimedia communications. That has motivated important standardization efforts, such as the IP Multimedia Subsystem (IMS) to support session control, mobility, and interoperability in all-IP next generation networks. Notwithstanding the central role of IMS in novel mobile multimedia, the potential of IMS-based service composition for the development of new classes of ready-to-use, energy-efficient, and cost-effective services is still widely unexplored. The paper proposes an original solution for the dynamic and standard-compliant redirection of incoming voice calls towards WiFi-equipped smart phones. The primary design guideline is to reduce energy consumption and service costs for the final user by automatically switching from the 3G to the WiFi infrastructure whenever possible. The proposal is fully compliant with the IMS standard and exploits the recently released IMS presence service to update device location and current communication opportunities. The reported experimental results point out that our solution, in a simple way and with full compliance with state-of-the-art industrially-accepted standards, can significantly increase battery lifetime without negative effects on call initiation delay.

Development of a tool for evaluating multimedia for surgical education.

Science.gov (United States)

Coughlan, Jane; Morar, Sonali S

2008-09-01

Educational multimedia has been designed to provide surgical trainees with expert operative information outside of the operating theater. The effectiveness of multimedia (e.g., CD-ROMs) for learning has been a common research topic since the 1990s. To date, however, little discussion has taken place on the mechanisms to evaluate the quality of multimedia-driven teaching. This may be because of a lack of research into the development of appropriate tools for evaluating multimedia, especially for surgical education. This paper reports on a small-scale pilot and exploratory study (n = 12) that developed a tool for surgical multimedia evaluation. The validity of the developed tool was established through adaptation of an existing tool, which was reviewed using experts in surgery, usability, and education. The reliability of the developed tool was tested with surgical trainees who used it to assess a multimedia CD-ROM created for teaching basic surgical skills. The findings contribute to an understanding of surgical trainees' experience of using educational multimedia, in terms of characteristics of the learning material for interface design and content and the process of developing evaluation tools, in terms of inclusion of appropriate assessment criteria. The increasing use of multimedia in medical education necessitates the development of standardized tools for determining the quality of teaching and learning. Little research exists into the development of such tools and so the present work stimulates discussion on how to evaluate surgical training.

Multimedia Pivot Tables for Multimedia Analytics on Image Collections

NARCIS (Netherlands)

Worring, M.; Koelma, D.; Zahálka, J.

2016-01-01

We propose a multimedia analytics solution for getting insight into image collections by extending the powerful analytic capabilities of pivot tables, found in the ubiquitous spreadsheets, to multimedia. We formalize the concept of multimedia pivot tables and give design rules and methods for the

An adaptive secret key-directed cryptographic scheme for secure transmission in wireless sensor networks

International Nuclear Information System (INIS)

Muhammad, K.; Jan, Z.; Khan, Z

2015-01-01

Wireless Sensor Networks (WSNs) are memory and bandwidth limited networks whose main goals are to maximize the network lifetime and minimize the energy consumption and transmission cost. To achieve these goals, different techniques of compression and clustering have been used. However, security is an open and major issue in WSNs for which different approaches are used, both in centralized and distributed WSNs' environments. This paper presents an adaptive cryptographic scheme for secure transmission of various sensitive parameters, sensed by wireless sensors to the fusion center for further processing in WSNs such as military networks. The proposed method encrypts the sensitive captured data of sensor nodes using various encryption procedures (bitxor operation, bits shuffling, and secret key based encryption) and then sends it to the fusion center. At the fusion center, the received encrypted data is decrypted for taking further necessary actions. The experimental results with complexity analysis, validate the effectiveness and feasibility of the proposed method in terms of security in WSNs. (author)

Cognitive streaming on android devices

NARCIS (Netherlands)

Torres Vega, M.; Mocanu, D.C.; Barresi, R.; Fortino, G.; Liotta, A.

2015-01-01

As the number of mobile devices increases, so do the complexity of wireless networks and the user's requirements. This tendency makes necessary for Multimedia Services to take the needed actions to adapt to the upcoming technology. A prominent example of this type of services is HTTP Adaptive Video

Adaptive Power Management for Wireless Base Station in Smart Grid Environment

OpenAIRE

Niyato, Dusit; Lu, Xiao; Wang, Ping

2014-01-01

The growing concerns of a global environmental change raises a revolution on the way of utilizing energy. In wireless industry, green wireless communications has recently gained increasing attention and is expected to play a major role in reduction of electrical power consumption. In particular, actions to promote energy saving of wireless communications with regard to environmental protection are becoming imperative. To this purpose, we study a green communication system model where wireless...

Self Adaptive Safe Provisioning of Wireless Power Using DCOPs

NARCIS (Netherlands)

Leeuwen, C.J. van; Yildirim, K.S.; Pawelczak, P.

2017-01-01

Wireless Power Transfer (WPT) technologies aim at getting rid of cables used by consumer devices for energy provision. As long distance WPT is becoming mature, the health impact of WPT becomes increasingly important to consider. In this paper we look at how to maximize the wireless power transfer to

An Adaptive Impedance Matching Network with Closed Loop Control Algorithm for Inductive Wireless Power Transfer.

Science.gov (United States)

Miao, Zhidong; Liu, Dake; Gong, Chen

2017-08-01

For an inductive wireless power transfer (IWPT) system, maintaining a reasonable power transfer efficiency and a stable output power are two most challenging design issues, especially when coil distance varies. To solve these issues, this paper presents a novel adaptive impedance matching network (IMN) for IWPT system. In our adaptive IMN IWPT system, the IMN is automatically reconfigured to keep matching with the coils and to adjust the output power adapting to coil distance variation. A closed loop control algorithm is used to change the capacitors continually, which can compensate mismatches and adjust output power simultaneously. The proposed adaptive IMN IWPT system is working at 125 kHz for 2 W power delivered to load. Comparing with the series resonant IWPT system and fixed IMN IWPT system, the power transfer efficiency of our system increases up to 31.79% and 60% when the coupling coefficient varies in a large range from 0.05 to 0.8 for 2 W output power.

An Adaptive Impedance Matching Network with Closed Loop Control Algorithm for Inductive Wireless Power Transfer

Science.gov (United States)

Miao, Zhidong; Liu, Dake

2017-01-01

For an inductive wireless power transfer (IWPT) system, maintaining a reasonable power transfer efficiency and a stable output power are two most challenging design issues, especially when coil distance varies. To solve these issues, this paper presents a novel adaptive impedance matching network (IMN) for IWPT system. In our adaptive IMN IWPT system, the IMN is automatically reconfigured to keep matching with the coils and to adjust the output power adapting to coil distance variation. A closed loop control algorithm is used to change the capacitors continually, which can compensate mismatches and adjust output power simultaneously. The proposed adaptive IMN IWPT system is working at 125 kHz for 2 W power delivered to load. Comparing with the series resonant IWPT system and fixed IMN IWPT system, the power transfer efficiency of our system increases up to 31.79% and 60% when the coupling coefficient varies in a large range from 0.05 to 0.8 for 2 W output power. PMID:28763011

Design of an effective energy receiving adapter for microwave wireless power transmission application

Directory of Open Access Journals (Sweden)

Peng Xu

2016-10-01

Full Text Available In this paper, we demonstrate the viability of an energy receiving adapter in a 8×8 array form with high power reception efficiency with the resonator of artificial electromagnetic absorber being used as the element. Unlike the conventional reported rectifying antenna resonators, both the size of the element and the separations between the elements are electrically small in our design. The energy collecting process is explained with an equivalent circuit model, and a RF combining network is designed to combine the captured AC power from each element to one main terminal for AC-to-DC conversion. The energy receiving adapter yields a total reception efficiency of 67% (including the wave capture efficiency of 86% and the AC-to-DC conversion efficiency of 78%, which is quite promising for microwave wireless power transmission.

Adaptive Square-Shaped Trajectory-Based Service Location Protocol in Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Hwa-Jung Lim

2010-04-01

Full Text Available In this paper we propose an adaptive square-shaped trajectory (ASST-based service location method to ensure load scalability in wireless sensor networks. This first establishes a square-shaped trajectory over the nodes that surround a target point computed by the hash function and any user can access it, using the hash. Both the width and the size of the trajectory are dynamically adjustable, depending on the number of queries made to the service information on the trajectory. The number of sensor nodes on the trajectory varies in proportion to the changing trajectory shape, allowing high loads to be distributed around the hot spot area.

A Least Square-Based Self-Adaptive Localization Method for Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Baoguo Yu

2016-01-01

Full Text Available In the wireless sensor network (WSN localization methods based on Received Signal Strength Indicator (RSSI, it is usually required to determine the parameters of the radio signal propagation model before estimating the distance between the anchor node and an unknown node with reference to their communication RSSI value. And finally we use a localization algorithm to estimate the location of the unknown node. However, this localization method, though high in localization accuracy, has weaknesses such as complex working procedure and poor system versatility. Concerning these defects, a self-adaptive WSN localization method based on least square is proposed, which uses the least square criterion to estimate the parameters of radio signal propagation model, which positively reduces the computation amount in the estimation process. The experimental results show that the proposed self-adaptive localization method outputs a high processing efficiency while satisfying the high localization accuracy requirement. Conclusively, the proposed method is of definite practical value.

Design of Optimized Multimedia Data Streaming Management Using OMDSM over Mobile Networks

Directory of Open Access Journals (Sweden)

Byungjoo Park

2017-01-01

Full Text Available Mobility management is an essential challenge for supporting reliable multimedia data streaming over wireless and mobile networks in the Internet of Things (IoT for location-based mobile marketing applications. The communications among mobile nodes for IoT need to have a seamless handover for delivering high quality multimedia services. The Internet Engineering Task Force (IETF mobility management schemes are the proposals for handling the routing of IPv6 packets to mobile nodes that have moved away from their home network. However, the standard mobility management scheme cannot prevent packet losses due to longer handover latency. In this article, a new enhanced data streaming route optimization scheme is introduced that uses an optimized Transmission Control Protocol (TCP realignment algorithm in order to prevent the packet disordering problem whenever the nodes in the IoT environment are communicating with each other. With the proposed scheme, data packets sequence realignment can be prevented, the packet traffic speed can be controlled, and the TCP performance can be improved. The experimental results show that managing the packet order in proposed new scheme remarkably increases the overall TCP performance over mobile networks within the IoT environment thus ensuring the high quality of service (QoS for multimedia data streaming in location-based mobile marketing applications.

Identifying Opportunities for Exploiting Cross-Layer Interactions in Adaptive Wireless Systems

Directory of Open Access Journals (Sweden)

Troy Weingart

2007-01-01

Full Text Available The flexibility of cognitive and software-defined radio heralds an opportunity for researchers to reexamine how network protocol layers operate with respect to providing quality of service aware transmission among wireless nodes. This opportunity is enhanced by the continued development of spectrally responsive devices—ones that can detect and respond to changes in the radio frequency environment. Present wireless network protocols define reliability and other performance-related tasks narrowly within layers. For example, the frame size employed on 802.11 can substantially influence the throughput, delay, and jitter experienced by an application, but there is no simple way to adapt this parameter. Furthermore, while the data link layer of 802.11 provides error detection capabilities across a link, it does not specify additional features, such as forward error correction schemes, nor does it provide a means for throttling retransmissions at the transport layer (currently, the data link and transport layer can function counterproductively with respect to reliability. This paper presents an analysis of the interaction of physical, data link, and network layer parameters with respect to throughput, bit error rate, delay, and jitter. The goal of this analysis is to identify opportunities where system designers might exploit cross-layer interactions to improve the performance of Voice over IP (VoIP, instant messaging (IM, and file transfer applications.

An Energy-Efficient Adaptive Clustering Protocol for Wireless Sensor Network

Directory of Open Access Journals (Sweden)

Lü Tao

2013-05-01

Full Text Available An energy-efficient adaptive clustering hierarchy EEACH in wireless sensor networks based on LEACH and LEACH-C is proposed in this paper. The main consideration is the LEACH cluster structure, each cluster is not uniform energy consumption; LEACH-C using a centralized algorithm can achieve better clustering, but do not contribute to the implementation of distributed. In EEACH, we analyzed the effects of different numbers of cluster member node on the network energy consumption; and re-planning time slice to balance the energy consumption of each cluster; and avoid the energy hole problem by reasonable cluster head selection algorithm. Its objective is to balance the energy consumption and maximize the network lifetime. Analysis and simulation results show that EEACH provides more uniform energy consumption among nodes and can prolong network lifetime compared to LEACH and LEACH-C.

An Integrated Multimedia Approach to Cultural Heritage e-Documents

NARCIS (Netherlands)

Smeulders, A.W.M.; Hardman, H.L.; Schreiber, G.; Geusebroek, J.M.

2002-01-01

We discuss access to e-documents from three different perspectives beyond the plain keyword web-search of the entire document. The first one is the situation-depending delivery of multimedia documents adapting the preferred form (picture, text, speech) to the available information capacity or need

Intelligent Flood Adaptive Context-aware System: How Wireless Sensors Adapt their Configuration based on Environmental Phenomenon Events

Directory of Open Access Journals (Sweden)

Jie SUN

2016-11-01

Full Text Available Henceforth, new generations of Wireless Sensor Networks (WSN have to be able to adapt their behavior to collect, from the study phenomenon, quality data for long periods of time. We have thus proposed a new formalization for the design and the implementation of context-aware systems relying on a WSN for the data collection. To illustrate this proposal, we also present an environmental use case: the study of flood events in a watershed. In this paper, we detail the simulation tool that we have developed in order to implement our model. We simulate several scenarios of context-aware systems to monitor a watershed. The data used for the simulation are the observation data of the French Orgeval watershed.

Multimedia: Why Invest?

Science.gov (United States)

Hirschbuhl, John J.

1992-01-01

Discusses the utilization of technology to assist the educational establishment deal with change. Topics addressed include multimedia metaphors such as graphical user interfaces; interactive videodisk systems; problems with current multimedia systems; a Multimedia Sampler developed at the University of North Carolina that includes applications…

Adaptive management of energy consumption, reliability and delay of wireless sensor node: Application to IEEE 802.15.4 wireless sensor node.

Science.gov (United States)

Kone, Cheick Tidjane; Mathias, Jean-Denis; De Sousa, Gil

2017-01-01

Designing a Wireless Sensor Network (WSN) to achieve a high Quality of Service (QoS) (network performance and durability) is a challenging problem. We address it by focusing on the performance of the 802.15.4 communication protocol because the IEEE 802.15.4 Standard is actually considered as one of the reference technologies in WSNs. In this paper, we propose to control the sustainable use of resources (i.e., energy consumption, reliability and timely packet transmission) of a wireless sensor node equipped with photovoltaic cells by an adaptive tuning not only of the MAC (Medium Access Control) parameters but also of the sampling frequency of the node. To do this, we use one of the existing control approaches, namely the viability theory, which aims to preserve the functions and the controls of a dynamic system in a set of desirable states. So, an analytical model, describing the evolution over time of nodal resources, is derived and used by a viability algorithm for the adaptive tuning of the IEEE 802.15.4 MAC protocol. The simulation analysis shows that our solution allows ensuring indefinitely, in the absence of hardware failure, the operations (lifetime duration, reliability and timely packet transmission) of an 802.15.4 WSN and one can temporarily increase the sampling frequency of the node beyond the regular sampling one. This latter brings advantages for agricultural and environmental applications such as precision agriculture, flood or fire prevention. Main results show that our current approach enable to send more information when critical events occur without the node runs out of energy. Finally, we argue that our approach is generic and can be applied to other types of WSN.

A Study of Application Layer Paradigm for Lower Layer Energy Saving Potentials in Cloud-Edge Social User Wireless Image Sharing

Directory of Open Access Journals (Sweden)

Wei Wang

2015-08-01

Full Text Available Energy saving becomes critical in modern cloud wireless multimedia and mobile communication systems. In this paper we propose to study a new paradigm named application layer Position-Value diversity for wireless image sharing for cloud-edge communications, which has significant energy saving potentials for modern wireless networking systems. In this new paradigm, saving energy is achieved by looking into application layer imaging traffic, in stead of MAC-PHY protocols at lower layers, and partitioning it into important positions and unimportant values. This paradigm could be integrated to existing wavelet-based tree compression, and truncation of image bit streams could be performed with regards to wireless communication energy budget estimation. Simulation results demonstrated that there are significant potentials of communication energy efficiency gain and Quality of Experience (QoE enhancement in wireless image communication systems.

A Content-Adaptive Analysis and Representation Framework for Audio Event Discovery from "Unscripted" Multimedia

Science.gov (United States)

Radhakrishnan, Regunathan; Divakaran, Ajay; Xiong, Ziyou; Otsuka, Isao

2006-12-01

We propose a content-adaptive analysis and representation framework to discover events using audio features from "unscripted" multimedia such as sports and surveillance for summarization. The proposed analysis framework performs an inlier/outlier-based temporal segmentation of the content. It is motivated by the observation that "interesting" events in unscripted multimedia occur sparsely in a background of usual or "uninteresting" events. We treat the sequence of low/mid-level features extracted from the audio as a time series and identify subsequences that are outliers. The outlier detection is based on eigenvector analysis of the affinity matrix constructed from statistical models estimated from the subsequences of the time series. We define the confidence measure on each of the detected outliers as the probability that it is an outlier. Then, we establish a relationship between the parameters of the proposed framework and the confidence measure. Furthermore, we use the confidence measure to rank the detected outliers in terms of their departures from the background process. Our experimental results with sequences of low- and mid-level audio features extracted from sports video show that "highlight" events can be extracted effectively as outliers from a background process using the proposed framework. We proceed to show the effectiveness of the proposed framework in bringing out suspicious events from surveillance videos without any a priori knowledge. We show that such temporal segmentation into background and outliers, along with the ranking based on the departure from the background, can be used to generate content summaries of any desired length. Finally, we also show that the proposed framework can be used to systematically select "key audio classes" that are indicative of events of interest in the chosen domain.

Multimedia Pivot Tables for Multimedia Analytics on Image Collections

OpenAIRE

Worring, M.; Koelma, D.; Zahálka, J.

2016-01-01

We propose a multimedia analytics solution for getting insight into image collections by extending the powerful analytic capabilities of pivot tables, found in the ubiquitous spreadsheets, to multimedia. We formalize the concept of multimedia pivot tables and give design rules and methods for the multimodal summarization, structuring, and browsing of the collection based on these tables, all optimized to support an analyst in getting structural and conclusive insights. Our proposed solution p...

Modular high-voltage bias generator powered by dual-looped self-adaptive wireless power transmission.

Science.gov (United States)

Xie, Kai; Huang, An-Feng; Li, Xiao-Ping; Guo, Shi-Zhong; Zhang, Han-Lu

2015-04-01

We proposed a modular high-voltage (HV) bias generator powered by a novel transmitter-sharing inductive coupled wireless power transmission technology, aimed to extend the generator's flexibility and configurability. To solve the problems caused through an uncertain number of modules, a dual-looped self-adaptive control method is proposed that is capable of tracking resonance frequency while maintaining a relatively stable induction voltage for each HV module. The method combines a phase-locked loop and a current feedback loop, which ensures an accurate resonance state and a relatively constant boost ratio for each module, simplifying the architecture of the boost stage and improving the total efficiency. The prototype was built and tested. The input voltage drop of each module is less than 14% if the module number varies from 3 to 10; resonance tracking is completed within 60 ms. The efficiency of the coupling structure reaches up to 95%, whereas the total efficiency approaches 73% for a rated output. Furthermore, this technology can be used in various multi-load wireless power supply applications.

An Efficient and Adaptive Mutual Authentication Framework for Heterogeneous Wireless Sensor Network-Based Applications

Directory of Open Access Journals (Sweden)

Pardeep Kumar

2014-02-01

Full Text Available Robust security is highly coveted in real wireless sensor network (WSN applications since wireless sensors’ sense critical data from the application environment. This article presents an efficient and adaptive mutual authentication framework that suits real heterogeneous WSN-based applications (such as smart homes, industrial environments, smart grids, and healthcare monitoring. The proposed framework offers: (i key initialization; (ii secure network (cluster formation (i.e., mutual authentication and dynamic key establishment; (iii key revocation; and (iv new node addition into the network. The correctness of the proposed scheme is formally verified. An extensive analysis shows the proposed scheme coupled with message confidentiality, mutual authentication and dynamic session key establishment, node privacy, and message freshness. Moreover, the preliminary study also reveals the proposed framework is secure against popular types of attacks, such as impersonation attacks, man-in-the-middle attacks, replay attacks, and information-leakage attacks. As a result, we believe the proposed framework achieves efficiency at reasonable computation and communication costs and it can be a safeguard to real heterogeneous WSN applications.

An efficient and adaptive mutual authentication framework for heterogeneous wireless sensor network-based applications.

Science.gov (United States)

Kumar, Pardeep; Ylianttila, Mika; Gurtov, Andrei; Lee, Sang-Gon; Lee, Hoon-Jae

2014-02-11

Robust security is highly coveted in real wireless sensor network (WSN) applications since wireless sensors' sense critical data from the application environment. This article presents an efficient and adaptive mutual authentication framework that suits real heterogeneous WSN-based applications (such as smart homes, industrial environments, smart grids, and healthcare monitoring). The proposed framework offers: (i) key initialization; (ii) secure network (cluster) formation (i.e., mutual authentication and dynamic key establishment); (iii) key revocation; and (iv) new node addition into the network. The correctness of the proposed scheme is formally verified. An extensive analysis shows the proposed scheme coupled with message confidentiality, mutual authentication and dynamic session key establishment, node privacy, and message freshness. Moreover, the preliminary study also reveals the proposed framework is secure against popular types of attacks, such as impersonation attacks, man-in-the-middle attacks, replay attacks, and information-leakage attacks. As a result, we believe the proposed framework achieves efficiency at reasonable computation and communication costs and it can be a safeguard to real heterogeneous WSN applications.

An Efficient and Adaptive Mutual Authentication Framework for Heterogeneous Wireless Sensor Network-Based Applications

Science.gov (United States)

Kumar, Pardeep; Ylianttila, Mika; Gurtov, Andrei; Lee, Sang-Gon; Lee, Hoon-Jae

2014-01-01

Robust security is highly coveted in real wireless sensor network (WSN) applications since wireless sensors' sense critical data from the application environment. This article presents an efficient and adaptive mutual authentication framework that suits real heterogeneous WSN-based applications (such as smart homes, industrial environments, smart grids, and healthcare monitoring). The proposed framework offers: (i) key initialization; (ii) secure network (cluster) formation (i.e., mutual authentication and dynamic key establishment); (iii) key revocation; and (iv) new node addition into the network. The correctness of the proposed scheme is formally verified. An extensive analysis shows the proposed scheme coupled with message confidentiality, mutual authentication and dynamic session key establishment, node privacy, and message freshness. Moreover, the preliminary study also reveals the proposed framework is secure against popular types of attacks, such as impersonation attacks, man-in-the-middle attacks, replay attacks, and information-leakage attacks. As a result, we believe the proposed framework achieves efficiency at reasonable computation and communication costs and it can be a safeguard to real heterogeneous WSN applications. PMID:24521942

Cultural and linguistic adaptation of a multimedia colorectal cancer screening decision aid for Spanish-speaking Latinos.

Science.gov (United States)

Ko, Linda K; Reuland, Daniel; Jolles, Monica; Clay, Rebecca; Pignone, Michael

2014-01-01

As the United States becomes more linguistically and culturally diverse, there is a need for effective health communication interventions that target diverse, vulnerable populations, including Latinos. To address such disparities, health communication interventionists often face the challenge to adapt existing interventions from English into Spanish in a way that retains essential elements of the original intervention while also addressing the linguistic needs and cultural perspectives of the target population. The authors describe the conceptual framework, context, rationale, methods, and findings of a formative research process used in creating a Spanish-language version of an evidence-based (English language) multimedia colorectal cancer screening decision aid. The multistep process included identification of essential elements of the existing intervention, literature review, assessment of the regional context and engagement of key stakeholders, and solicitation of direct input from target population. The authors integrated these findings in the creation of the new adapted intervention. They describe how they used this process to identify and integrate sociocultural themes such as personalism (personalismo), familism (familismo), fear (miedo), embarrassment (verguenza), power distance (respeto), machismo, and trust (confianza) into the Spanish-language decision aid.

Minimizing SIP Session Re-Setup Delay over Wireless Link in 3G Handover Scenarios

Directory of Open Access Journals (Sweden)

Moon Bongkyo

2010-01-01

Full Text Available The delay in transmitting SIP messages over the wireless link for session resetup at handover is still major bottleneck for interactive multimedia service. In this paper, a proxy agent-based scheme is proposed to minimize the SIP session setup delay over a wireless link in 3G inter-subnet handover scenarios. This scheme is based on the two characteristics. One is that the major factor of SIP session re-setup delay is generally caused by the retransmissions in the unreliable wireless links, and the other is that most of the fields in request messages as well as response messages are duplicated when a set of SIP messages are exchanged during session re-setup procedure. In this scheme, no change is required in the SIP message processing except for the proxy agents in both BS and MH.

Green partial packet recovery in wireless sensor networks

KAUST Repository

Daghistani, Anas; Ben Khalifa, Abderrahman; Showail, Ahmad; Shihada, Basem

2015-01-01

wireless sensor motes. We propose Green-Frag, a novel adaptive partial packet recovery mechanism that is energy friendly. It can help prolonging the battery life of wireless sensor motes that are usually resource constrained. It dynamically partitions

Benchmarking multimedia performance

Science.gov (United States)

Zandi, Ahmad; Sudharsanan, Subramania I.

1998-03-01

With the introduction of faster processors and special instruction sets tailored to multimedia, a number of exciting applications are now feasible on the desktops. Among these is the DVD playback consisting, among other things, of MPEG-2 video and Dolby digital audio or MPEG-2 audio. Other multimedia applications such as video conferencing and speech recognition are also becoming popular on computer systems. In view of this tremendous interest in multimedia, a group of major computer companies have formed, Multimedia Benchmarks Committee as part of Standard Performance Evaluation Corp. to address the performance issues of multimedia applications. The approach is multi-tiered with three tiers of fidelity from minimal to full compliant. In each case the fidelity of the bitstream reconstruction as well as quality of the video or audio output are measured and the system is classified accordingly. At the next step the performance of the system is measured. In many multimedia applications such as the DVD playback the application needs to be run at a specific rate. In this case the measurement of the excess processing power, makes all the difference. All these make a system level, application based, multimedia benchmark very challenging. Several ideas and methodologies for each aspect of the problems will be presented and analyzed.

Abuse of disabled parking: Reforming public's attitude through persuasive multimedia strategy

Science.gov (United States)

Yahaya, W. A. J. W.; Zain, M. Z. M.

2014-02-01

Attitude is one of the factors that contribute to the abuse of disabled parking. The attitude's components are affective, cognitive and behavioral and may be formed in various ways including learning and persuasion. Using learning and persuasion approach, this study has produced a persuasive multimedia aiming to form a positive attitude toward disabled persons in order to minimize the rate of disabled parking abuse. The persuasive multimedia was developed using Principle of Social Learning draws from Persuasive Technology as learning strategy at macro persuasion level, and modality and redundancy principles draw from Multimedia Learning Principles as design strategy at micro persuasion level. In order to measure the effectiveness of the persuasive multimedia, 93 respondents were selected in a 2 × 2 quasi experimental research design for experiment. Attitude components of affective, cognitive and behavioral were measured using adapted instrument from the Multi Dimensional Attitudes Scale toward Persons With Disabilities (MAS). Result of the study shows that the persuasive multimedia which designed based on Social Learning Theory at macro persuasion level is capable of forming positive attitude toward disabled person. The cognitive component of the attitude found to be the most responsive component. In term of design strategy at the micro persuasion level, modality found to be the most significant strategy compare to redundancy. While males are more responsive to the persuasive multimedia compare to females.

Multimedia services in intelligent environments advances in recommender systems

CERN Document Server

Virvou, Maria; Jain, Lakhmi

2013-01-01

Multimedia services are now commonly used in various activities in the daily lives of humans. Related application areas include services that allow access to large depositories of information, digital libraries, e-learning and e-education, e-government and e-governance, e-commerce and e-auctions, e-entertainment, e-health and e-medicine, and e-legal services, as well as their mobile counterparts (i.e., m-services). Despite the tremendous growth of multimedia services over the recent years, there is an increasing demand for their further development. This demand is driven by the ever-increasing desire of society for easy accessibility to information in friendly, personalized and adaptive environments. In this book at hand, we examine recent Advances in Recommender Systems. Recommender systems are crucial in multimedia services, as they aim at protecting the service users from information overload. The book includes nine chapters, which present various recent research results in recommender systems. This resear...

Multimedia Based E-learning : Design and Integration of Multimedia Content in E-learning

Directory of Open Access Journals (Sweden)

Abdulaziz Omar Alsadhan

2014-05-01

Full Text Available The advancement in multimedia and information technologies also have impacted the way of imparting education. This advancement has led to rapid use of e learning systems and has enabled greater integration of multimedia content into e learning systems. This paper present a model for development of e learning systems based on multimedia content. The model is called “Multimedia based e learning” and is loosely based on waterfall software development model. This model consists of three distinct phases; Multimedia Content Modelling, Multimedia content Development, Multimedia content Integration. These three phases are further sub divided into 7 different activities which are analysis, design, technical requirements, content development, content production & integration, implementation and evaluation. This model defines a general framework that can be applied for the development of e learning systems across all disciplines and subjects.

Examining Multimedia Competencies for Educational Technologists in Higher Education

Science.gov (United States)

Iqdami, Muhammad Nazil; Branch, Robert Maribe

2016-01-01

The authors investigated educational technology multimedia competencies for professionals who work in higher education institutions. Similar studies have been proposed, but none of them have focused on competencies required in the context of higher education. An online survey adapting sixteen competency factors from a study conducted by Rizhaupt…

The promise of multimedia technology for STI/HIV prevention: frameworks for understanding improved facilitator delivery and participant learning.

Science.gov (United States)

Khan, Maria R; Epperson, Matthew W; Gilbert, Louisa; Goddard, Dawn; Hunt, Timothy; Sarfo, Bright; El-Bassel, Nabila

2012-10-01

There is increasing excitement about multimedia sexually transmitted infection (STI) and HIV prevention interventions, yet there has been limited discussion of how use of multimedia technology may improve STI/HIV prevention efforts. The purpose of this paper is to describe the mechanisms through which multimedia technology may work to improve the delivery and uptake of intervention material. We present conceptual frameworks describing how multimedia technology may improve intervention delivery by increasing standardization and fidelity to the intervention material and the participant's ability to learn by improving attention, cognition, emotional engagement, skills-building, and uptake of sensitive material about sexual and drug risks. In addition, we describe how the non-multimedia behavioral STI/HIV prevention intervention, Project WORTH, was adapted into a multimedia format for women involved in the criminal justice system and provide examples of how multimedia activities can more effectively target key mediators of behavioral change in this intervention.

Tangible Multimedia: A Case Study for Bringing Tangibility into Multimedia Learning

Science.gov (United States)

Tsong, Chau Kien; Chong, Toh Seong; Samsudin, Zarina

2012-01-01

Multimedia augmented with tangible objects is an area that has not been explored. Current multimedia systems lack the natural elements that allow young children to learn tangibly and intuitively. In view of this, we propose a research to merge tangible objects with multimedia for preschoolers, and propose to term it as "tangible…

Multimedia Information Retrieval

CERN Document Server

Rueger, Stefan

2009-01-01

At its very core multimedia information retrieval means the process of searching for and finding multimedia documents; the corresponding research field is concerned with building the best possible multimedia search engines. The intriguing bit here is that the query itself can be a multimedia excerpt: For example, when you walk around in an unknown place and stumble across an interesting landmark, would it not be great if you could just take a picture with your mobile phone and send it to a service that finds a similar picture in a database and tells you more about the building -- and about its

QOS-aware error recovery in wireless body sensor networks using adaptive network coding.

Science.gov (United States)

Razzaque, Mohammad Abdur; Javadi, Saeideh S; Coulibaly, Yahaya; Hira, Muta Tah

2014-12-29

Wireless body sensor networks (WBSNs) for healthcare and medical applications are real-time and life-critical infrastructures, which require a strict guarantee of quality of service (QoS), in terms of latency, error rate and reliability. Considering the criticality of healthcare and medical applications, WBSNs need to fulfill users/applications and the corresponding network's QoS requirements. For instance, for a real-time application to support on-time data delivery, a WBSN needs to guarantee a constrained delay at the network level. A network coding-based error recovery mechanism is an emerging mechanism that can be used in these systems to support QoS at very low energy, memory and hardware cost. However, in dynamic network environments and user requirements, the original non-adaptive version of network coding fails to support some of the network and user QoS requirements. This work explores the QoS requirements of WBSNs in both perspectives of QoS. Based on these requirements, this paper proposes an adaptive network coding-based, QoS-aware error recovery mechanism for WBSNs. It utilizes network-level and user-/application-level information to make it adaptive in both contexts. Thus, it provides improved QoS support adaptively in terms of reliability, energy efficiency and delay. Simulation results show the potential of the proposed mechanism in terms of adaptability, reliability, real-time data delivery and network lifetime compared to its counterparts.

Energy-Efficient Wireless Communication for Mobile Multimedia Terminals

NARCIS (Netherlands)

Smit, L.T.; Smit, Gerardus Johannes Maria; Hurink, Johann L.; Ferscha, Alois; Schreiner, Wolfgang; Kotsis, Gabriele; Ibrahim, Ismail Khalil

This paper presents a control system that adapts a WCDMA receiver at run-time to minimize the energy consumption while providing an adequate Quality of Service (QoS). The adaptation is done at run-time, because of the dynamic environment of a mobile receiver. Simulations show that run-time

Energy Efficient Wireless Communication for Mobile Multimedia Terminals

NARCIS (Netherlands)

Smit, L.T.; Smit, Gerardus Johannes Maria; Hurink, Johann L.

2004-01-01

This paper presents a control system that adapts a WCDMA receiver at run-time to minimize the energy consumption while providing an adequate Quality of Service (QoS). The adaptation is done at run-time, because of the dynamic environment of a mobile receiver. Simulations show that run-time

Delivering Live Multimedia Streams to Mobile Hosts in a Wireless Internet with Multiple Content Aggregators

NARCIS (Netherlands)

Bianchi, G.; Hesselman, C.E.W.; Eertink, E.H.; Eertink, Henk; Kermani, P.; Lee, S.J.; Widya, I.A.; Huizer, E.

We consider the distribution of channels of live multimedia content (e.g., radio or TV broadcasts) via multiple content aggregators. In our work, an aggregator receives channels from content sources and redistributes them to a potentially large number of mobile hosts. Each aggregator can offer a

Handoff Between a Wireless Local Area Network (WLAN and a Wide Area Network (UMTS

Directory of Open Access Journals (Sweden)

J. Sánchez–García

2009-04-01

Full Text Available With the appearance of wireless data networks with variable coverage, band width and handoff strategies, in addition to the growing need of mobile nodes to freely roam among these networks, the support of an interoperable handoff strategy for hybrid wireless data networks is a requirement that needs to be addressed. The current trend in wireless data networks is to offer multimedia access to mobile users by employing the wireless local area network (WLAN standard IEEE802.11 while the user is located indoors; on the other hand, 3rd generation wireless networks (WAN are being deployed to provide coverage while the user is located outdoors. As a result, the mobile node will require a handoff mechanism to allow the user to roam between WLAN and WAN environments; up to this date several strategies have been proposed (Sattari et al., 2004 and HyoJin, 2007 in the literature, however, none of these have been standardized to date. To support this interoperability, the mobile node must be equipped with configurable wireless inetrfaces to support the handoff between the WLAN and the WAN networks. In this work a new algorithm is proposed to allow a mobile node to roam between a wireless local area network (IEEE802.11 and a WAN base station (UMTS, while employing IP mobility support. The algorithm is implemented in simulation, using the Network Simulator 2.

Cross-Layer Handover Scheme for Multimedia Communications in Next Generation Wireless Networks

Directory of Open Access Journals (Sweden)

Lin Chun-Cheng

2010-01-01

Full Text Available In order to achieve seamless handover for real-time applications in the IP Multimedia Subsystem (IMS of next generation network, a multiprotocol combined handover mechanism is proposed in this paper. We combine SIP (Session Initiation Protocol, FMIP (Fast Mobile IPv6 Protocol, and MIH (Media Independent Handover protocols by cross-layer design and optimize those protocols' signaling flows to improve the performance of vertical handover. Theoretical analysis and simulation results illustrate that our proposed mechanism performs better than the original SIP and MIH combined handover mechanism in terms of service interruption time and packet loss.

75 FR 49528 - Freescale Semiconductor, Inc., Networking and Multimedia Group (“NMG”) Excluding the Multimedia...

Science.gov (United States)

2010-08-13

... services for chips used in networking and multimedia products. The company reports that workers leased from... Multimedia Applications Division, including on-site workers of Synergy Services, Craftcorp, Directions..., Inc., Networking and Multimedia Group (``NMG'') Excluding the Multimedia Applications Division...

QoS Adaptation in Multimedia Multicast Conference Applications for E-Learning Services

Science.gov (United States)

Deusdado, Sérgio; Carvalho, Paulo

2006-01-01

The evolution of the World Wide Web service has incorporated new distributed multimedia conference applications, powering a new generation of e-learning development and allowing improved interactivity and prohuman relations. Groupware applications are increasingly representative in the Internet home applications market, however, the Quality of…

Cultural and Linguistic Adaptation of a Multimedia Colorectal Cancer Screening Decision Aid for Spanish Speaking Latinos

Science.gov (United States)

Ko, Linda K.; Reuland, Daniel; Jolles, Monica; Clay, Rebecca; Pignone, Michael

2014-01-01

As the United States becomes more linguistically and culturally diverse, there is a need for effective health communication interventions that target diverse and most vulnerable populations. Latinos also have the lowest colorectal (CRC) screening rates of any ethnic group in the U.S. To address such disparities, health communication interventionists are often faced with the challenge to adapt existing interventions from English into Spanish in a way that retains essential elements of the original intervention while also addressing the linguistic needs and cultural perspectives of the target population. We describe the conceptual framework, context, rationale, methods, and findings of a formative research process used in creating a Spanish language version of an evidenced-based (English language) multimedia CRC screening decision aid. Our multi-step process included identification of essential elements of the existing intervention, literature review, assessment of the regional context and engagement of key stakeholders, and solicitation of direct input from target population. We integrated these findings in the creation of the new adapted intervention. We describe how we used this process to identify and integrate socio-cultural themes such as personalism (personalismo), familism (familismo), fear (miedo), embarrassment (verguenza), power distance (respeto), machismo, and trust (confianza) into the Spanish language decision aid. PMID:24328496

Ad hoc mobile wireless networks principles, protocols and applications

CERN Document Server

Sarkar, Subir Kumar; Puttamadappa, C

2007-01-01

Ad hoc mobile wireless networks have seen increased adaptation in a variety of disciplines because they can be deployed with simple infrastructures and virtually no central administration. In particular, the development of ad hoc wireless and sensor networks provides tremendous opportunities in areas including disaster recovery, defense, health care, and industrial environments. Ad Hoc Mobile Wireless Networks: Principles, Protocols and Applications explains the concepts, mechanisms, design, and performance of these systems. It presents in-depth explanations of the latest wireless technologies

Multimedia and Decision-Making Process

Directory of Open Access Journals (Sweden)

Ovidiu-Alin DOBRICAN

2009-01-01

Full Text Available Multimedia technology has changed the way we use computers. Multimedia transforms com-puters into a second person. Multimedia technology has made it possible for us to see, hear, read, feel, and talk to computers. Multimedia technology has transformed our use and understanding of computers. On the other hand, multimedia presentation is one of the fastest-growing sectors of the computer industry. Applications have appeared in many areas, such as training, education, business presentation, merchandising, and communications.

Considering User's Access Pattern in Multimedia File Systems

Science.gov (United States)

Cho, KyoungWoon; Ryu, YeonSeung; Won, Youjip; Koh, Kern

2002-12-01

Legacy buffer cache management schemes for multimedia server are grounded at the assumption that the application sequentially accesses the multimedia file. However, user access pattern may not be sequential in some circumstances, for example, in distance learning application, where the user may exploit the VCR-like function(rewind and play) of the system and accesses the particular segments of video repeatedly in the middle of sequential playback. Such a looping reference can cause a significant performance degradation of interval-based caching algorithms. And thus an appropriate buffer cache management scheme is required in order to deliver desirable performance even under the workload that exhibits looping reference behavior. We propose Adaptive Buffer cache Management(ABM) scheme which intelligently adapts to the file access characteristics. For each opened file, ABM applies either the LRU replacement or the interval-based caching depending on the Looping Reference Indicator, which indicates that how strong temporally localized access pattern is. According to our experiment, ABM exhibits better buffer cache miss ratio than interval-based caching or LRU, especially when the workload exhibits not only sequential but also looping reference property.

Multimedia Information Networks in Social Media

Science.gov (United States)

Cao, Liangliang; Qi, Guojun; Tsai, Shen-Fu; Tsai, Min-Hsuan; Pozo, Andrey Del; Huang, Thomas S.; Zhang, Xuemei; Lim, Suk Hwan

The popularity of personal digital cameras and online photo/video sharing community has lead to an explosion of multimedia information. Unlike traditional multimedia data, many new multimedia datasets are organized in a structural way, incorporating rich information such as semantic ontology, social interaction, community media, geographical maps, in addition to the multimedia contents by themselves. Studies of such structured multimedia data have resulted in a new research area, which is referred to as Multimedia Information Networks. Multimedia information networks are closely related to social networks, but especially focus on understanding the topics and semantics of the multimedia files in the context of network structure. This chapter reviews different categories of recent systems related to multimedia information networks, summarizes the popular inference methods used in recent works, and discusses the applications related to multimedia information networks. We also discuss a wide range of topics including public datasets, related industrial systems, and potential future research directions in this field.

Multimedia image and video processing

CERN Document Server

Guan, Ling

2012-01-01

As multimedia applications have become part of contemporary daily life, numerous paradigm-shifting technologies in multimedia processing have emerged over the last decade. Substantially updated with 21 new chapters, Multimedia Image and Video Processing, Second Edition explores the most recent advances in multimedia research and applications. This edition presents a comprehensive treatment of multimedia information mining, security, systems, coding, search, hardware, and communications as well as multimodal information fusion and interaction. Clearly divided into seven parts, the book begins w

An Autonomous Self-Aware and Adaptive Fault Tolerant Routing Technique for Wireless Sensor Networks.

Science.gov (United States)

Abba, Sani; Lee, Jeong-A

2015-08-18

We propose an autonomous self-aware and adaptive fault-tolerant routing technique (ASAART) for wireless sensor networks. We address the limitations of self-healing routing (SHR) and self-selective routing (SSR) techniques for routing sensor data. We also examine the integration of autonomic self-aware and adaptive fault detection and resiliency techniques for route formation and route repair to provide resilience to errors and failures. We achieved this by using a combined continuous and slotted prioritized transmission back-off delay to obtain local and global network state information, as well as multiple random functions for attaining faster routing convergence and reliable route repair despite transient and permanent node failure rates and efficient adaptation to instantaneous network topology changes. The results of simulations based on a comparison of the ASAART with the SHR and SSR protocols for five different simulated scenarios in the presence of transient and permanent node failure rates exhibit a greater resiliency to errors and failure and better routing performance in terms of the number of successfully delivered network packets, end-to-end delay, delivered MAC layer packets, packet error rate, as well as efficient energy conservation in a highly congested, faulty, and scalable sensor network.

Adaptive Cross-Layer Distributed Energy-Efficient Resource Allocation Algorithms for Wireless Data Networks

Directory of Open Access Journals (Sweden)

Daniela Saturnino

2008-10-01

Full Text Available The issue of adaptive and distributed cross-layer resource allocation for energy efficiency in uplink code-division multiple-access (CDMA wireless data networks is addressed. The resource allocation problems are formulated as noncooperative games wherein each terminal seeks to maximize its own energy efficiency, namely, the number of reliably transmitted information symbols per unit of energy used for transmission. The focus of this paper is on the issue of adaptive and distributed implementation of policies arising from this approach, that is, it is assumed that only readily available measurements, such as the received data, are available at the receiver in order to play the considered games. Both single-cell and multicell networks are considered. Stochastic implementations of noncooperative games for power allocation, spreading code allocation, and choice of the uplink (linear receiver are thus proposed, and analytical results describing the convergence properties of selected stochastic algorithms are also given. Extensive simulation results show that, in many instances of practical interest, the proposed stochastic algorithms approach with satisfactory accuracy the performance of nonadaptive games, whose implementation requires much more prior information.

Multimedia services in intelligent environments recommendation services

CERN Document Server

Virvou, Maria; Jain, Lakhmi

2013-01-01

Multimedia services are now commonly used in various activities in the daily lives of humans. Related application areas include services that allow access to large depositories of information, digital libraries, e-learning and e-education, e-government and e-governance, e-commerce and e-auctions, e-entertainment, e-health and e-medicine, and e-legal services, as well as their mobile counterparts (i.e., m-services). Despite the tremendous growth of multimedia services over the recent years, there is an increasing demand for their further development. This demand is driven by the ever-increasing desire of society for easy accessibility to information in friendly, personalized and adaptive environments. In this book at hand, we examine recent Recommendation Services. Recommendation services appear in the mobile environment, medicine/biology, tourism, education, and so on. The book includes ten chapters, which present various recently developed recommendation services. This research book is directed to professors...

Cross-Layer optimization of the packet loss rate in mobile videoconferencing applications

OpenAIRE

Rivera-Rodríguez, R.; Olivares-Domínguez, O. E.; Serrano-Santoyo, A.

2010-01-01

Videoconferencing transmission over wireless channels presents relevant challenges in mobile scenarios at vehicular speeds. Previous contributions are focused on the optimization of the transmission of multimedia and delay-sensitive applications over the forward link. In this paper, a new Quality of Service (QoS) parameter adaptation scheme is proposed. This scheme applies the Cross-Layer Design technique on the reverse link of an 1xEV-DO Revision 0 channel. As the wireless channel parameters...

QoS-Aware Error Recovery in Wireless Body Sensor Networks Using Adaptive Network Coding

Directory of Open Access Journals (Sweden)

Mohammad Abdur Razzaque

2014-12-01

Full Text Available Wireless body sensor networks (WBSNs for healthcare and medical applications are real-time and life-critical infrastructures, which require a strict guarantee of quality of service (QoS, in terms of latency, error rate and reliability. Considering the criticality of healthcare and medical applications, WBSNs need to fulfill users/applications and the corresponding network’s QoS requirements. For instance, for a real-time application to support on-time data delivery, a WBSN needs to guarantee a constrained delay at the network level. A network coding-based error recovery mechanism is an emerging mechanism that can be used in these systems to support QoS at very low energy, memory and hardware cost. However, in dynamic network environments and user requirements, the original non-adaptive version of network coding fails to support some of the network and user QoS requirements. This work explores the QoS requirements of WBSNs in both perspectives of QoS. Based on these requirements, this paper proposes an adaptive network coding-based, QoS-aware error recovery mechanism for WBSNs. It utilizes network-level and user-/application-level information to make it adaptive in both contexts. Thus, it provides improved QoS support adaptively in terms of reliability, energy efficiency and delay. Simulation results show the potential of the proposed mechanism in terms of adaptability, reliability, real-time data delivery and network lifetime compared to its counterparts.

QoS-Aware Error Recovery in Wireless Body Sensor Networks Using Adaptive Network Coding

Science.gov (United States)

Razzaque, Mohammad Abdur; Javadi, Saeideh S.; Coulibaly, Yahaya; Hira, Muta Tah

2015-01-01

Wireless body sensor networks (WBSNs) for healthcare and medical applications are real-time and life-critical infrastructures, which require a strict guarantee of quality of service (QoS), in terms of latency, error rate and reliability. Considering the criticality of healthcare and medical applications, WBSNs need to fulfill users/applications and the corresponding network's QoS requirements. For instance, for a real-time application to support on-time data delivery, a WBSN needs to guarantee a constrained delay at the network level. A network coding-based error recovery mechanism is an emerging mechanism that can be used in these systems to support QoS at very low energy, memory and hardware cost. However, in dynamic network environments and user requirements, the original non-adaptive version of network coding fails to support some of the network and user QoS requirements. This work explores the QoS requirements of WBSNs in both perspectives of QoS. Based on these requirements, this paper proposes an adaptive network coding-based, QoS-aware error recovery mechanism for WBSNs. It utilizes network-level and user-/application-level information to make it adaptive in both contexts. Thus, it provides improved QoS support adaptively in terms of reliability, energy efficiency and delay. Simulation results show the potential of the proposed mechanism in terms of adaptability, reliability, real-time data delivery and network lifetime compared to its counterparts. PMID:25551485

Application of multimedia image technology in engineering report demonstration system

Science.gov (United States)

Lili, Jiang

2018-03-01

With the rapid development of global economic integration, people’s strong desire for a wide range of global exchanges and interactions has been promoted, and there are more unprecedented convenient means for people to know the world and even to transform the world. At this stage, we realize that the traditional mode of work has become difficult to adapt to the changing trends of the world and informatization, multimedia, science and technology have become the mainstream of the times. Therefore, this paper will mainly analyze the present situation of the project report demonstration system and the key points of the work and put forward with pertinence specific application strategy of the integration with multimedia image technology.

Transmission History Based Distributed Adaptive Contention Window Adjustment Algorithm Cooperating with Automatic Rate Fallback for Wireless LANs

Science.gov (United States)

Ogawa, Masakatsu; Hiraguri, Takefumi; Nishimori, Kentaro; Takaya, Kazuhiro; Murakawa, Kazuo

This paper proposes and investigates a distributed adaptive contention window adjustment algorithm based on the transmission history for wireless LANs called the transmission-history-based distributed adaptive contention window adjustment (THAW) algorithm. The objective of this paper is to reduce the transmission delay and improve the channel throughput compared to conventional algorithms. The feature of THAW is that it adaptively adjusts the initial contention window (CWinit) size in the binary exponential backoff (BEB) algorithm used in the IEEE 802.11 standard according to the transmission history and the automatic rate fallback (ARF) algorithm, which is the most basic algorithm in automatic rate controls. This effect is to keep CWinit at a high value in a congested state. Simulation results show that the THAW algorithm outperforms the conventional algorithms in terms of the channel throughput and delay, even if the timer in the ARF is changed.

Adaptive and Reactive Security for Wireless Sensor Networks

National Research Council Canada - National Science Library

Stankovic, John A

2007-01-01

.... WSNs are also susceptible to malicious, non-random security attacks. For example, a wireless sensor network deployed in remote regions to detect and classify targets could be rendered inoperative by various security attacks...

Abuse of disabled parking: Reforming public's attitude through persuasive multimedia strategy

International Nuclear Information System (INIS)

Yahaya, W A J W; Zain, M Z M

2014-01-01

Attitude is one of the factors that contribute to the abuse of disabled parking. The attitude's components are affective, cognitive and behavioral and may be formed in various ways including learning and persuasion. Using learning and persuasion approach, this study has produced a persuasive multimedia aiming to form a positive attitude toward disabled persons in order to minimize the rate of disabled parking abuse. The persuasive multimedia was developed using Principle of Social Learning draws from Persuasive Technology as learning strategy at macro persuasion level, and modality and redundancy principles draw from Multimedia Learning Principles as design strategy at micro persuasion level. In order to measure the effectiveness of the persuasive multimedia, 93 respondents were selected in a 2 × 2 quasi experimental research design for experiment. Attitude components of affective, cognitive and behavioral were measured using adapted instrument from the Multi Dimensional Attitudes Scale toward Persons With Disabilities (MAS). Result of the study shows that the persuasive multimedia which designed based on Social Learning Theory at macro persuasion level is capable of forming positive attitude toward disabled person. The cognitive component of the attitude found to be the most responsive component. In term of design strategy at the micro persuasion level, modality found to be the most significant strategy compare to redundancy. While males are more responsive to the persuasive multimedia compare to females

Exploiting Multimedia in Creating and Analysing Multimedia Web Archives

Directory of Open Access Journals (Sweden)

Jonathon S. Hare

2014-04-01

Full Text Available The data contained on the web and the social web are inherently multimedia and consist of a mixture of textual, visual and audio modalities. Community memories embodied on the web and social web contain a rich mixture of data from these modalities. In many ways, the web is the greatest resource ever created by human-kind. However, due to the dynamic and distributed nature of the web, its content changes, appears and disappears on a daily basis. Web archiving provides a way of capturing snapshots of (parts of the web for preservation and future analysis. This paper provides an overview of techniques we have developed within the context of the EU funded ARCOMEM (ARchiving COmmunity MEMories project to allow multimedia web content to be leveraged during the archival process and for post-archival analysis. Through a set of use cases, we explore several practical applications of multimedia analytics within the realm of web archiving, web archive analysis and multimedia data on the web in general.

Cross-Layer Optimal Rate Allocation for Heterogeneous Wireless Multicast

Directory of Open Access Journals (Sweden)

Amr Mohamed

2009-01-01

Full Text Available Heterogeneous multicast is an efficient communication scheme especially for multimedia applications running over multihop networks. The term heterogeneous refers to the phenomenon when multicast receivers in the same session require service at different rates commensurate with their capabilities. In this paper, we address the problem of resource allocation for a set of heterogeneous multicast sessions over multihop wireless networks. We propose an iterative algorithm that achieves the optimal rates for a set of heterogeneous multicast sessions such that the aggregate utility for all sessions is maximized. We present the formulation of the multicast resource allocation problem as a nonlinear optimization model and highlight the cross-layer framework that can solve this problem in a distributed ad hoc network environment with asynchronous computations. Our simulations show that the algorithm achieves optimal resource utilization, guarantees fairness among multicast sessions, provides flexibility in allocating rates over different parts of the multicast sessions, and adapts to changing conditions such as dynamic channel capacity and node mobility. Our results show that the proposed algorithm not only provides flexibility in allocating resources across multicast sessions, but also increases the aggregate system utility and improves the overall system throughput by almost 30% compared to homogeneous multicast.

Opportunities and challenges for optical wireless: the competitive advantage of free space telecommunications links in today's crowded marketplace

Science.gov (United States)

Carbonneau, Theresa H.; Wisely, David R.

1998-01-01

Never before has the opportunity for terrestrial optical wireless communications links been so great. The high data rates attainable, up to OC-24, make it a very attractive and cost effective alternative to traditional fiber optic and microwave links. With today's demand for interactive multimedia-based applications, such as video conferencing and telemedicine, optical wireless products are the only ones that can provide the needed bandwidth in situations when it is too costly or impossible to install fiber optic cable. Recent developments in laser and optics technologies, in addition to auto beam tracking, permit transmission units to achieve excellent performance rates in all weather conditions.

Multimedia and ubiquitous engineering MUE 2013

CERN Document Server

Ng, Joseph; Jeong, Hwa; Waluyo, Borgy

2013-01-01

The new multimedia standards (for example, MPEG-21) facilitate the seamless integration of multiple modalities into interoperable multimedia frameworks, transforming the way people work and interact with multimedia data. These key technologies and multimedia solutions interact and collaborate with each other in increasingly effective ways, contributing to the multimedia revolution and having a significant impact across a wide spectrum of consumer, business, healthcare, education, and governmental domains. Multimedia and Ubiquitous Engineering provides an opportunity for academic and industry professionals to discuss recent progress in the area of multimedia and ubiquitous environment including models and systems, new directions, novel applications associated with the utilization and acceptance of ubiquitous computing devices and systems.

From early wireless to Everest.

Science.gov (United States)

Allen, A

1998-01-01

Medical information has been transmitted using wireless technologies for almost 80 years. A "wired wireless" electronic stethoscope was developed by the U.S. Army Signal Corps in the early 1920's, for potential use in ship-to-shore transmission of cardiac sounds. [Winters SR. Diagnosis by wireless. Scientific American June 11, 1921, p. 465] Today, wireless is used in a wide range of medical applications and at sites from transoceanic air flights to offshore oil platforms to Mt. Everest. 'Wireless LANs' are often used in medical environments. Typically, nurses and physicians in a hospital or clinic use hand-held "wireless thin client" pen computers that exchange patient information and images with the hospital server. Numerous companies, such as Fujitsu (article below) and Cruise Technologies (www.cruisetech.com) manufacture handheld pen-entry computers. One company, LXE, integrates radio-frequency (RF) enhanced hand-held computers specifically designed for production use within a wireless LAN (www.lxe.com). Other companies (Proxim, Symbol, and others) supply the wireless RF LAN infrastructure for the enterprise. Unfortunately, there have been problems with widespread deployment of wireless LANs. Perhaps the biggest impediment has been the lack of standards. Although an international standard (IEEE 802.11) was adopted in 1997, most wireless LAN products still are not compatible with the equipment of competing companies. A problem with the current standard for LAN adapters is that throughput is limited to 3 Mbps--compared to at least 10 Mbps, and often 100 Mbps, in a hard-wired Ethernet LAN. An II Mbps standard is due out in the next year or so, but it will be at least 2 years before standards-compliant products are available. This story profiles some of the ways that wireless is being used to overcome gaps in terrestrial and within-enterprise communication.

Adaptive Code Division Multiple Access Protocol for Wireless Network-on-Chip Architectures

Science.gov (United States)

Vijayakumaran, Vineeth

Massive levels of integration following Moore's Law ushered in a paradigm shift in the way on-chip interconnections were designed. With higher and higher number of cores on the same die traditional bus based interconnections are no longer a scalable communication infrastructure. On-chip networks were proposed enabled a scalable plug-and-play mechanism for interconnecting hundreds of cores on the same chip. Wired interconnects between the cores in a traditional Network-on-Chip (NoC) system, becomes a bottleneck with increase in the number of cores thereby increasing the latency and energy to transmit signals over them. Hence, there has been many alternative emerging interconnect technologies proposed, namely, 3D, photonic and multi-band RF interconnects. Although they provide better connectivity, higher speed and higher bandwidth compared to wired interconnects; they also face challenges with heat dissipation and manufacturing difficulties. On-chip wireless interconnects is one other alternative proposed which doesn't need physical interconnection layout as data travels over the wireless medium. They are integrated into a hybrid NOC architecture consisting of both wired and wireless links, which provides higher bandwidth, lower latency, lesser area overhead and reduced energy dissipation in communication. However, as the bandwidth of the wireless channels is limited, an efficient media access control (MAC) scheme is required to enhance the utilization of the available bandwidth. This thesis proposes using a multiple access mechanism such as Code Division Multiple Access (CDMA) to enable multiple transmitter-receiver pairs to send data over the wireless channel simultaneously. It will be shown that such a hybrid wireless NoC with an efficient CDMA based MAC protocol can significantly increase the performance of the system while lowering the energy dissipation in data transfer. In this work it is shown that the wireless NoC with the proposed CDMA based MAC protocol

An Autonomous Self-Aware and Adaptive Fault Tolerant Routing Technique for Wireless Sensor Networks

Science.gov (United States)

Abba, Sani; Lee, Jeong-A

2015-01-01

We propose an autonomous self-aware and adaptive fault-tolerant routing technique (ASAART) for wireless sensor networks. We address the limitations of self-healing routing (SHR) and self-selective routing (SSR) techniques for routing sensor data. We also examine the integration of autonomic self-aware and adaptive fault detection and resiliency techniques for route formation and route repair to provide resilience to errors and failures. We achieved this by using a combined continuous and slotted prioritized transmission back-off delay to obtain local and global network state information, as well as multiple random functions for attaining faster routing convergence and reliable route repair despite transient and permanent node failure rates and efficient adaptation to instantaneous network topology changes. The results of simulations based on a comparison of the ASAART with the SHR and SSR protocols for five different simulated scenarios in the presence of transient and permanent node failure rates exhibit a greater resiliency to errors and failure and better routing performance in terms of the number of successfully delivered network packets, end-to-end delay, delivered MAC layer packets, packet error rate, as well as efficient energy conservation in a highly congested, faulty, and scalable sensor network. PMID:26295236

Design issues and caching strategies for CD-ROM-based multimedia storage

Science.gov (United States)

Shastri, Vijnan; Rajaraman, V.; Jamadagni, H. S.; Venkat-Rangan, P.; Sampath-Kumar, Srihari

1996-03-01

CD-ROMs have proliferated as a distribution media for desktop machines for a large variety of multimedia applications (targeted for a single-user environment) like encyclopedias, magazines and games. With CD-ROM capacities up to 3 GB being available in the near future, they will form an integral part of Video on Demand (VoD) servers to store full-length movies and multimedia. In the first section of this paper we look at issues related to the single- user desktop environment. Since these multimedia applications are highly interactive in nature, we take a pragmatic approach, and have made a detailed study of the multimedia application behavior in terms of the I/O request patterns generated to the CD-ROM subsystem by tracing these patterns. We discuss prefetch buffer design and seek time characteristics in the context of the analysis of these traces. We also propose an adaptive main-memory hosted cache that receives caching hints from the application to reduce the latency when the user moves from one node of the hyper graph to another. In the second section we look at the use of CD-ROM in a VoD server and discuss the problem of scheduling multiple request streams and buffer management in this scenario. We adapt the C-SCAN (Circular SCAN) algorithm to suit the CD-ROM drive characteristics and prove that it is optimal in terms of buffer size management. We provide computationally inexpensive relations by which this algorithm can be implemented. We then propose an admission control algorithm which admits new request streams without disrupting the continuity of playback of the previous request streams. The algorithm also supports operations such as fast forward and replay. Finally, we discuss the problem of optimal placement of MPEG streams on CD-ROMs in the third section.

The machine in multimedia analytics

NARCIS (Netherlands)

Zahálka, J.

2017-01-01

This thesis investigates the role of the machine in multimedia analytics, a discipline that combines visual analytics with multimedia analysis algorithms in order to unlock the potential of multimedia collections as sources of knowledge in scientific and applied domains. Specifically, the central

Enhanced P2P Services Providing Multimedia Content

Directory of Open Access Journals (Sweden)

E. Ardizzone

2007-01-01

To address this major limitation, we propose an original image and video sharing system, in which a user is able to interactively search interesting resources by means of content-based image and video retrieval techniques. In order to limit the network traffic load, maximizing the usefulness of each peer contacted in the query process, we also propose the adoption of an adaptive overlay routing algorithm, exploiting compact representations of the multimedia resources shared by each peer. Experimental results confirm the validity of the proposed approach, that is capable of dynamically adapting the network topology to peer interests, on the basis of query interactions among users.

An FPGA-Based Adaptable 200 MHz Bandwidth Channel Sounder for Wireless Communication Channel Characterisation

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David L. Ndzi

2011-01-01

Full Text Available This paper describes the development of a fast adaptable FPGA-based wideband channel sounder with signal bandwidths of up to 200 MHz and channel sampling rates up to 5.4 kHz. The application of FPGA allows the user to vary the number of real-time channel response averages, channel sampling interval, and duration of measurement. The waveform, bandwidth, and frequency resolution of the sounder can be adapted for any channel under investigation. The design approach and technology used has led to a reduction in size and weight by more than 60%. This makes the sounder ideal for mobile time-variant wireless communication channels studies. Averaging allows processing gains of up to 30 dB to be achieved for measurement in weak signal conditions. The technique applied also improves reliability, reduces power consumption, and has shifted sounder design complexity from hardware to software. Test results show that the sounder can detect very small-scale variations in channels.

A Bio-Inspired QoS-Oriented Handover Model in Heterogeneous Wireless Networks

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Daxin Tian

2014-01-01

Full Text Available We propose a bio-inspired model for making handover decision in heterogeneous wireless networks. It is based on an extended attractor selection model, which is biologically inspired by the self-adaptability and robustness of cellular response to the changes in dynamic environments. The goal of the proposed model is to guarantee multiple terminals’ satisfaction by meeting the QoS requirements of those terminals’ applications, and this model also attempts to ensure the fairness of network resources allocation, in the meanwhile, to enable the QoS-oriented handover decision adaptive to dynamic wireless environments. Some numerical simulations are preformed to validate our proposed bio-inspired model in terms of adaptive attractor selection in different noisy environments. And the results of some other simulations prove that the proposed handover scheme can adapt terminals’ network selection to the varying wireless environment and benefits the QoS of multiple terminal applications simultaneously and automatically. Furthermore, the comparative analysis also shows that the bio-inspired model outperforms the utility function based handover decision scheme in terms of ensuring a better QoS satisfaction and a better fairness of network resources allocation in dynamic heterogeneous wireless networks.

An Adaptive Connectivity-based Centroid Algorithm for Node Positioning in Wireless Sensor Networks

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Aries Pratiarso

2015-06-01

Full Text Available In wireless sensor network applications, the position of nodes is randomly distributed following the contour of the observation area. A simple solution without any measurement tools is provided by range-free method. However, this method yields the coarse estimating position of the nodes. In this paper, we propose Adaptive Connectivity-based (ACC algorithm. This algorithm is a combination of Centroid as range-free based algorithm, and hop-based connectivity algorithm. Nodes have a possibility to estimate their own position based on the connectivity level between them and their reference nodes. Each node divides its communication range into several regions where each of them has a certain weight depends on the received signal strength. The weighted value is used to obtain the estimated position of nodes. Simulation result shows that the proposed algorithm has up to 3 meter error of estimated position on 100x100 square meter observation area, and up to 3 hop counts for 80 meters' communication range. The proposed algorithm performs an average error positioning up to 10 meters better than Weighted Centroid algorithm. Keywords: adaptive, connectivity, centroid, range-free.

Semantic multimedia analysis and processing

CERN Document Server

Spyrou, Evaggelos; Mylonas, Phivos

2014-01-01

Broad in scope, Semantic Multimedia Analysis and Processing provides a complete reference of techniques, algorithms, and solutions for the design and the implementation of contemporary multimedia systems. Offering a balanced, global look at the latest advances in semantic indexing, retrieval, analysis, and processing of multimedia, the book features the contributions of renowned researchers from around the world. Its contents are based on four fundamental thematic pillars: 1) information and content retrieval, 2) semantic knowledge exploitation paradigms, 3) multimedia personalization, and 4)

Performance of a Two-Level Call Admission Control Scheme for DS-CDMA Wireless Networks

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Fapojuwo Abraham O

2007-01-01

Full Text Available We propose a two-level call admission control (CAC scheme for direct sequence code division multiple access (DS-CDMA wireless networks supporting multimedia traffic and evaluate its performance. The first-level admission control assigns higher priority to real-time calls (also referred to as class 0 calls in gaining access to the system resources. The second level admits nonreal-time calls (or class 1 calls based on the resources remaining after meeting the resource needs for real-time calls. However, to ensure some minimum level of performance for nonreal-time calls, the scheme reserves some resources for such calls. The proposed two-level CAC scheme utilizes the delay-tolerant characteristic of non-real-time calls by incorporating a queue to temporarily store those that cannot be assigned resources at the time of initial access. We analyze and evaluate the call blocking, outage probability, throughput, and average queuing delay performance of the proposed two-level CAC scheme using Markov chain theory. The analytic results are validated by simulation results. The numerical results show that the proposed two-level CAC scheme provides better performance than the single-level CAC scheme. Based on these results, it is concluded that the proposed two-level CAC scheme serves as a good solution for supporting multimedia applications in DS-CDMA wireless communication systems.

Performance of a Two-Level Call Admission Control Scheme for DS-CDMA Wireless Networks

Directory of Open Access Journals (Sweden)

Abraham O. Fapojuwo

2007-11-01

Full Text Available We propose a two-level call admission control (CAC scheme for direct sequence code division multiple access (DS-CDMA wireless networks supporting multimedia traffic and evaluate its performance. The first-level admission control assigns higher priority to real-time calls (also referred to as class 0 calls in gaining access to the system resources. The second level admits nonreal-time calls (or class 1 calls based on the resources remaining after meeting the resource needs for real-time calls. However, to ensure some minimum level of performance for nonreal-time calls, the scheme reserves some resources for such calls. The proposed two-level CAC scheme utilizes the delay-tolerant characteristic of non-real-time calls by incorporating a queue to temporarily store those that cannot be assigned resources at the time of initial access. We analyze and evaluate the call blocking, outage probability, throughput, and average queuing delay performance of the proposed two-level CAC scheme using Markov chain theory. The analytic results are validated by simulation results. The numerical results show that the proposed two-level CAC scheme provides better performance than the single-level CAC scheme. Based on these results, it is concluded that the proposed two-level CAC scheme serves as a good solution for supporting multimedia applications in DS-CDMA wireless communication systems.

Mathematics for multimedia

CERN Document Server

Wickerhauser, Mladen Victor

2003-01-01

Mathematics and Multimedia focuses on the mathematics behind multimedia applications. This timely and thoroughly modern text is a rigorous survey of selected results from algebra and analysis, requiring only undergraduate math skills.The topics are `gems' chosen for their usefulness in understanding and creating application software for multimedia signal processing and communication.The book is aimed at a wide audience, including computer science and mathematics majors and those interested in employing mathematics in multimedia design and implementation. For the instructor, the material is divided into six chapters that may be presented in six lecture hours each. Thus, the entire text may be covered in one semester, with time left for examinations and student projects. For the student,there are more than 100 exercises with complete solutions, and numerous example programs in Standard C. Each chapter ends with suggestions for further reading. A companion website provides more insight for both instructors and s...

An Energy-Efficient and High-Quality Video Transmission Architecture in Wireless Video-Based Sensor Networks

Directory of Open Access Journals (Sweden)

Yasaman Samei

2008-08-01

Full Text Available Technological progress in the fields of Micro Electro-Mechanical Systems (MEMS and wireless communications and also the availability of CMOS cameras, microphones and small-scale array sensors, which may ubiquitously capture multimedia content from the field, have fostered the development of low-cost limited resources Wireless Video-based Sensor Networks (WVSN. With regards to the constraints of videobased sensor nodes and wireless sensor networks, a supporting video stream is not easy to implement with the present sensor network protocols. In this paper, a thorough architecture is presented for video transmission over WVSN called Energy-efficient and high-Quality Video transmission Architecture (EQV-Architecture. This architecture influences three layers of communication protocol stack and considers wireless video sensor nodes constraints like limited process and energy resources while video quality is preserved in the receiver side. Application, transport, and network layers are the layers in which the compression protocol, transport protocol, and routing protocol are proposed respectively, also a dropping scheme is presented in network layer. Simulation results over various environments with dissimilar conditions revealed the effectiveness of the architecture in improving the lifetime of the network as well as preserving the video quality.

An Energy-Efficient and High-Quality Video Transmission Architecture in Wireless Video-Based Sensor Networks.

Science.gov (United States)

Aghdasi, Hadi S; Abbaspour, Maghsoud; Moghadam, Mohsen Ebrahimi; Samei, Yasaman

2008-08-04

Technological progress in the fields of Micro Electro-Mechanical Systems (MEMS) and wireless communications and also the availability of CMOS cameras, microphones and small-scale array sensors, which may ubiquitously capture multimedia content from the field, have fostered the development of low-cost limited resources Wireless Video-based Sensor Networks (WVSN). With regards to the constraints of videobased sensor nodes and wireless sensor networks, a supporting video stream is not easy to implement with the present sensor network protocols. In this paper, a thorough architecture is presented for video transmission over WVSN called Energy-efficient and high-Quality Video transmission Architecture (EQV-Architecture). This architecture influences three layers of communication protocol stack and considers wireless video sensor nodes constraints like limited process and energy resources while video quality is preserved in the receiver side. Application, transport, and network layers are the layers in which the compression protocol, transport protocol, and routing protocol are proposed respectively, also a dropping scheme is presented in network layer. Simulation results over various environments with dissimilar conditions revealed the effectiveness of the architecture in improving the lifetime of the network as well as preserving the video quality.

Traffic Agents for Improving QoS in Mixed Infrastructure and Ad Hoc Modes Wireless LAN

Directory of Open Access Journals (Sweden)

Yuan Hai-Feng

2006-01-01

Full Text Available As an important complement to infrastructured wireless networks, mobile ad hoc networks (MANET are more flexible in providing wireless access services, but more difficult in meeting different quality of service (QoS requirements for mobile customers. Both infrastructure and ad hoc network structures are supported in wireless local area networks (WLAN, which can offer high data-rate wireless multimedia services to the mobile stations (MSs in a limited geographical area. For those out-of-coverage MSs, how to effectively connect them to the access point (AP and provide QoS support is a challenging issue. By mixing the infrastructure and the ad hoc modes in WLAN, we propose in this paper a new coverage improvement scheme that can identify suitable idle MSs in good service zones as traffic agents (TAs to relay traffic from those out-of-coverage MSs to the AP. The service coverage area of WLAN is then expanded. The QoS requirements (e.g., bandwidth of those MSs are considered in the selection process of corresponding TAs. Mathematical analysis, verified by computer simulations, shows that the proposed TA scheme can effectively reduce blocking probability when traffic load is light.

Integrating Multimedia and Physics Problems

Science.gov (United States)

Titus, Aaron P.

1997-11-01

Although expert problem solvers typically use pictorial representations when solving problems, novices tend to proceed from the given problem statement to a mathematical solution without first developing a visual representation of the problem. For this reason, multimedia may be an effective tool to enhance students' success at solving problems. However, merely presenting a video of motion described in a problem is not necessarily the most effective method as was found in a recent study of students' responses on Web-based homework questions. Rather, multimedia-focused problems, where data relevant to solving the problem is embedded in a video or animation, may be the best use of multimedia in problem solving. Examples of multimedia-enhanced problems and multimedia-focused problems will be demonstrated, and their differences from "traditional" problems will be highlighted. Recommendations on the use of multimedia with problem solving and preliminary data on students' success at solving these problems will be discussed.

Effectief leren van multimedia

NARCIS (Netherlands)

Kester, Liesbeth

2013-01-01

Kester, L. (2012, March). Effectief leren van multimedia [Effective learning from multimedia]. Keynote presented at a miniconference Learning Sciences of the Open University of the Netherlands, Eindhoven, the Netherlands.

The development of interactive multimedia based on auditory, intellectually, repetition in repetition algorithm learning to increase learning outcome

Science.gov (United States)

Munir; Sutarno, H.; Aisyah, N. S.

2018-05-01

This research aims to find out how the development of interactive multimedia based on auditory, intellectually, and repetition can improve student learning outcomes. This interactive multimedia is developed through 5 stages. Analysis stages include the study of literature, questionnaire, interviews and observations. The design phase is done by the database design, flowchart, storyboards and repetition algorithm material while the development phase is done by the creation of web-based framework. Presentation material is adapted to the model of learning such as auditory, intellectually, repetition. Auditory points are obtained by recording the narrative material that presented by a variety of intellectual points. Multimedia as a product is validated by material and media experts. Implementation phase conducted on grade XI-TKJ2 SMKN 1 Garut. Based on index’s gain, an increasing of student learning outcomes in this study is 0.46 which is fair due to interest of student in using interactive multimedia. While the multimedia assessment earned 84.36% which is categorized as very well.

Cognitive Security of Wireless Communication Systems in the Physical Layer

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Mustafa Harun Yılmaz

2017-01-01

Full Text Available While the wireless communication systems provide the means of connectivity nearly everywhere and all the time, communication security requires more attention. Even though current efforts provide solutions to specific problems under given circumstances, these methods are neither adaptive nor flexible enough to provide security under the dynamic conditions which make the security breaches an important concern. In this paper, a cognitive security (CS concept for wireless communication systems in the physical layer is proposed with the aim of providing a comprehensive solution to wireless security problems. The proposed method will enable the comprehensive security to ensure a robust and reliable communication in the existence of adversaries by providing adaptive security solutions in the communication systems by exploiting the physical layer security from different perspective. The adaptiveness relies on the fact that radio adapts its propagation characteristics to satisfy secure communication based on specific conditions which are given as user density, application specific adaptation, and location within CS concept. Thus, instead of providing any type of new security mechanism, it is proposed that radio can take the necessary precautions based on these conditions before the attacks occur. Various access scenarios are investigated to enable the CS while considering these conditions.

An 802.11 n wireless local area network transmission scheme for wireless telemedicine applications.

Science.gov (United States)

Lin, C F; Hung, S I; Chiang, I H

2010-10-01

In this paper, an 802.11 n transmission scheme is proposed for wireless telemedicine applications. IEEE 802.11n standards, a power assignment strategy, space-time block coding (STBC), and an object composition Petri net (OCPN) model are adopted. With the proposed wireless system, G.729 audio bit streams, Joint Photographic Experts Group 2000 (JPEG 2000) clinical images, and Moving Picture Experts Group 4 (MPEG-4) video bit streams achieve a transmission bit error rate (BER) of 10-7, 10-4, and 103 simultaneously. The proposed system meets the requirements prescribed for wireless telemedicine applications. An essential feature of this proposed transmission scheme is that clinical information that requires a high quality of service (QoS) is transmitted at a high power transmission rate with significant error protection. For maximizing resource utilization and minimizing the total transmission power, STBC and adaptive modulation techniques are used in the proposed 802.11 n wireless telemedicine system. Further, low power, direct mapping (DM), low-error protection scheme, and high-level modulation are adopted for messages that can tolerate a high BER. With the proposed transmission scheme, the required reliability of communication can be achieved. Our simulation results have shown that the proposed 802.11 n transmission scheme can be used for developing effective wireless telemedicine systems.

An Effective Multimedia Item Shell Design for Individualized Education: The Crome Project

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Irene Cheng

2008-01-01

Full Text Available There are several advantages to creating multimedia item types and applying computer-based adaptive testing in education. First is the capability to motivate learning by making the learners feel more engaged and in an interactive environment. Second is a better concept representation, which is not possible in conventional multiple-choice tests. Third is the advantage of individualized curriculum design, rather than a curriculum designed for an average student. Fourth is a good choice of the next question, associated with the appropriate difficulty level based on a student's response to the current question. However, many issues need to be addressed when achieving these goals, including: (a the large number of item types required to represent the current multiple-choice questions in multimedia formats, (b the criterion used to determine the difficulty level of a multimedia question item, and (c the methodology applied to the question selection process for individual students. In this paper, we propose a multimedia item shell design that not only reduces the number of item types required, but also computes difficulty level of an item automatically. The concept of question seed is introduced to make content creation more cost-effective. The proposed item shell framework facilitates efficient communication between user responses at the client, and the scoring agents integrated with a student ability assessor at the server. We also describe approaches for automatically estimating difficulty level of questions, and discuss preliminary evaluation of multimedia item types by students.

Multimedia Presentation and Transmission Standards and Their Support for Automatic Analysis, Conversion and Scaling: A Survey

National Research Council Canada - National Science Library

Koivisto, A

2000-01-01

.... Another recent trend has been user-adaptive services, which most of the popular search engines already provide through customizable front ends as well as a wide range of audio and multimedia search facilities...

Building multimedia data warehouses from distributed data

Directory of Open Access Journals (Sweden)

Tania Cerquitelli

2004-01-01

Full Text Available La mediación de datos multimedia está caracterizada por tres aspectos importantes: la integración de datos multimedia, la arquitectura de sistema y una evaluación global de las búsquedas. El problema de la mediación multimedia puede ser visto desde un punto de vista arquitectónico en el que deben identificarse arquitecturas de mediación adecuadas, adaptadas a las características de los datos multimedia (como por ejemplo, volumen vs. costos de comunicación y ancho de banda. Debido a las características de los datos multimedia (distribución, homogeneidad, volumen, etc., el proceso de integración requiere de tiempo y recursos. La contribución de este artículo se asocia con la explotación de los datos multimedia. Se proporcionan los mecanismos para analizar las colecciones de datos multimedia provenientes de fuentes heterogéneas y distribuidas. Como solución se propone un servicio de búsqueda para datos multimedia distribuidos, adaptados para crear depósitos de datos multimedia.

Design of Range Adaptive Wireless Power Transfer System Using Non-coaxial Coils

Science.gov (United States)

Yang, Dongsheng; Won, Sokhui; Hong, Huan

2017-05-01

Wireless Power Transfer (WPT) is a remarkable technology because of its convenience and applicability in harsh environment. Particularly, Magnetic Coupling WPT (MC-WPT) is a proper method to midrange power transfer, but the frequency splitting at over-coupling range, which is related with transfer distance, is challenge of transmission efficiency. In order to overcome this phenomenon, recently the range adaptive WPT is proposed. In this paper, we aim to the type with a set of non-coaxial driving coils, so that this may remove the connection wires from PA (Power Amplifier) to driving coil. And, when the radius of driving coil is changed, on the different gaps between driving and TX coils, coupling coefficient between these is computed in both cases of coaxial and non-coaxial configurations. In addition, the designing steps for 4-coil WPT system using non-coaxial coils are described with the example. Finally, the reliability of this topology has been proved and simulated with PSPICE.

Moodle 2.5 multimedia

CERN Document Server

Fernandes, João

2013-01-01

A tutorial-based guide where readers can work through practical examples that clearly describe how to create multimedia applications using Moodle and integrate existing multimedia resources into Moodle courses.If you are a teacher or trainer who runs online courses and has a basic understanding of Moodle, this book will be ideal for you. It is not necessary to have an advanced technical background to create multimedia elements as the tasks will be simple, not time consuming, and will be practical for everyday use.

Pemanfaatan Multimedia sebagai Media Penyuluhan Kesehatan Gigi

Directory of Open Access Journals (Sweden)

Hestieyonini Hadnyawati

2015-10-01

Full Text Available The effort of suppression promotion and preventive as practice principles of "paradigma sehat" are concept which announcement by Departemen Kesehatan Republik Indonesia in framework reach Indonesia Sehat 2010. This effort as well as possible to get done by everyone Indonesia peoples, with the holistic through way dental education. For this application dental education needed medium. Multimedia are application various medium which different for associate and serve information in form text, audio, chart, animation, and video. Multimedia find occupy somebody for keep 90% what he read, hear, se, mention and done. Using multimedia as dental education medium can be used CD/VCD multimedia module, multimedia presentation, and multimedia web. With this reminder, so using multimedia technology find service as alternative medium for public dental education.

Analytical approach to cross-layer protocol optimization in wireless sensor networks

Science.gov (United States)

Hortos, William S.

2008-04-01

In the distributed operations of route discovery and maintenance, strong interaction occurs across mobile ad hoc network (MANET) protocol layers. Quality of service (QoS) requirements of multimedia service classes must be satisfied by the cross-layer protocol, along with minimization of the distributed power consumption at nodes and along routes to battery-limited energy constraints. In previous work by the author, cross-layer interactions in the MANET protocol are modeled in terms of a set of concatenated design parameters and associated resource levels by multivariate point processes (MVPPs). Determination of the "best" cross-layer design is carried out using the optimal control of martingale representations of the MVPPs. In contrast to the competitive interaction among nodes in a MANET for multimedia services using limited resources, the interaction among the nodes of a wireless sensor network (WSN) is distributed and collaborative, based on the processing of data from a variety of sensors at nodes to satisfy common mission objectives. Sensor data originates at the nodes at the periphery of the WSN, is successively transported to other nodes for aggregation based on information-theoretic measures of correlation and ultimately sent as information to one or more destination (decision) nodes. The "multimedia services" in the MANET model are replaced by multiple types of sensors, e.g., audio, seismic, imaging, thermal, etc., at the nodes; the QoS metrics associated with MANETs become those associated with the quality of fused information flow, i.e., throughput, delay, packet error rate, data correlation, etc. Significantly, the essential analytical approach to MANET cross-layer optimization, now based on the MVPPs for discrete random events occurring in the WSN, can be applied to develop the stochastic characteristics and optimality conditions for cross-layer designs of sensor network protocols. Functional dependencies of WSN performance metrics are described in

Multimedia Matrix: A Cognitive Strategy for Designers.

Science.gov (United States)

Sherry, Annette C.

This instructional development project evaluates the effect of a matrix-based strategy to assist multimedia authors in acquiring and applying principles for effective multimedia design. The Multimedia Matrix, based on the Park and Hannafin "Twenty Principles and Implications for Interactive Multimedia" design, displays a condensed…

A new channel allocation scheme and performance optimizing for mobile multimedia wireless networks

Institute of Scientific and Technical Information of China (English)

ZHAO Fang-ming; JIANG Ling-ge; MA Ming-da

2008-01-01

A multimedia channel allocation scheme is proposed and studied in terms of the connection-level QoS. A new traffic model based on multidimensional Markov chain is developed considering the traffic charac-teristic of two special periods of time. And the pre-emptive priority strategies are used to classify real-time serv-ices and non-real-time services. Real-time service is given higher priority for its allowance to pre-empt channels used by non-real-time service. Considering the mobility of persons in a day, which affects the mobile user's den-sity, the simulation was conducted involving the two pre-emptive priority strategies. The result of some compari-sons shows the feasibility of the proposed scheme.

Wireless networking for the dental office: current wireless standards and security protocols.

Science.gov (United States)

Mupparapu, Muralidhar; Arora, Sarika

2004-11-15

Digital radiography has gained immense popularity in dentistry today in spite of the early difficulty for the profession to embrace the technology. The transition from film to digital has been happening at a faster pace in the fields of Orthodontics, Oral Surgery, Endodontics, Periodontics, and other specialties where the radiographic images (periapical, bitewing, panoramic, cephalometric, and skull radiographs) are being acquired digitally, stored within a server locally, and eventually accessed for diagnostic purposes, along with the rest of the patient data via the patient management software (PMS). A review of the literature shows the diagnostic performance of digital radiography is at least comparable to or even better than that of conventional radiography. Similarly, other digital diagnostic tools like caries detectors, cephalometric analysis software, and digital scanners were used for many years for the diagnosis and treatment planning purposes. The introduction of wireless charged-coupled device (CCD) sensors in early 2004 (Schick Technologies, Long Island City, NY) has moved digital radiography a step further into the wireless era. As with any emerging technology, there are concerns that should be looked into before adapting to the wireless environment. Foremost is the network security involved in the installation and usage of these wireless networks. This article deals with the existing standards and choices in wireless technologies that are available for implementation within a contemporary dental office. The network security protocols that protect the patient data and boost the efficiency of modern day dental clinics are enumerated.

Displays enabling mobile multimedia

Science.gov (United States)

Kimmel, Jyrki

2007-02-01

With the rapid advances in telecommunications networks, mobile multimedia delivery to handsets is now a reality. While a truly immersive multimedia experience is still far ahead in the mobile world, significant advances have been made in the constituent audio-visual technologies to make this become possible. One of the critical components in multimedia delivery is the mobile handset display. While such alternatives as headset-style near-to-eye displays, autostereoscopic displays, mini-projectors, and roll-out flexible displays can deliver either a larger virtual screen size than the pocketable dimensions of the mobile device can offer, or an added degree of immersion by adding the illusion of the third dimension in the viewing experience, there are still challenges in the full deployment of such displays in real-life mobile communication terminals. Meanwhile, direct-view display technologies have developed steadily, and can provide a development platform for an even better viewing experience for multimedia in the near future. The paper presents an overview of the mobile display technology space with an emphasis on the advances and potential in developing direct-view displays further to meet the goal of enabling multimedia in the mobile domain.

A Dynamically Adaptable Impedance-Matching System for Midrange Wireless Power Transfer with Misalignment

Directory of Open Access Journals (Sweden)

Thuc Phi Duong

2015-07-01

Full Text Available To enable the geometrical freedom envisioned for wireless power transfer (WPT, fast dynamic adaptation to unpredictable changes in receiver position is needed. In this paper, we propose an adaptive impedance-searching system that achieves good impedance matching quickly. For fast and robust operation, the proposed method consists of three steps: system calibration, coarse search, and fine search. The proposed WPT system is characterized using distance variation and lateral and angular misalignment between coils. The measured results indicate that the proposed method significantly reduces searching time from a few minutes to approximately one second. Furthermore, the proposed system achieves impedance matching with good accuracy. The robust impedance-searching capability of the proposed system significantly improves power transfer efficiency. At 6.78 MHz, we achieve a maximum efficiency of 89.7% and a high efficiency of >80% up to a distance of 50 cm. When the center-to-center misalignment is 35 cm, the efficiency is improved from 48.4% to 74.1% with the proposed method. At a distance of 40 cm, the efficiency is higher than 74% for up to 60° of angular rotation. These results agree well with the simulated results obtained using a lumped-element circuit model.

Analyzing the factors affecting network lifetime cluster-based wireless sensor network

International Nuclear Information System (INIS)

Malik, A.S.; Qureshi, A.

2010-01-01

Cluster-based wireless sensor networks enable the efficient utilization of the limited energy resources of the deployed sensor nodes and hence prolong the node as well as network lifetime. Low Energy Adaptive Clustering Hierarchy (Leach) is one of the most promising clustering protocol proposed for wireless sensor networks. This paper provides the energy utilization and lifetime analysis for cluster-based wireless sensor networks based upon LEACH protocol. Simulation results identify some important factors that induce unbalanced energy utilization between the sensor nodes and hence affect the network lifetime in these types of networks. These results highlight the need for a standardized, adaptive and distributed clustering technique that can increase the network lifetime by further balancing the energy utilization among sensor nodes. (author)

Service Migration from Cloud to Multi-tier Fog Nodes for Multimedia Dissemination with QoE Support.

Science.gov (United States)

Rosário, Denis; Schimuneck, Matias; Camargo, João; Nobre, Jéferson; Both, Cristiano; Rochol, Juergen; Gerla, Mario

2018-01-24

A wide range of multimedia services is expected to be offered for mobile users via various wireless access networks. Even the integration of Cloud Computing in such networks does not support an adequate Quality of Experience (QoE) in areas with high demands for multimedia contents. Fog computing has been conceptualized to facilitate the deployment of new services that cloud computing cannot provide, particularly those demanding QoE guarantees. These services are provided using fog nodes located at the network edge, which is capable of virtualizing their functions/applications. Service migration from the cloud to fog nodes can be actuated by request patterns and the timing issues. To the best of our knowledge, existing works on fog computing focus on architecture and fog node deployment issues. In this article, we describe the operational impacts and benefits associated with service migration from the cloud to multi-tier fog computing for video distribution with QoE support. Besides that, we perform the evaluation of such service migration of video services. Finally, we present potential research challenges and trends.

A distributed multimedia toolbox

NARCIS (Netherlands)

Scholten, Johan; Jansen, P.G.

1997-01-01

Emphasis of our research lies on the application of realtime multimedia technology: tele-teaching, teleconferencing and collaborative work. To support this research we need a real-time environment that supports rapid prototyping of distributed multimedia applications. Because other systems were not

Multimedia database retrieval technology and applications

CERN Document Server

Muneesawang, Paisarn; Guan, Ling

2014-01-01

This book explores multimedia applications that emerged from computer vision and machine learning technologies. These state-of-the-art applications include MPEG-7, interactive multimedia retrieval, multimodal fusion, annotation, and database re-ranking. The application-oriented approach maximizes reader understanding of this complex field. Established researchers explain the latest developments in multimedia database technology and offer a glimpse of future technologies. The authors emphasize the crucial role of innovation, inspiring users to develop new applications in multimedia technologies

Multimedia security watermarking, steganography, and forensics

CERN Document Server

Shih, Frank Y

2012-01-01

Multimedia Security: Watermarking, Steganography, and Forensics outlines essential principles, technical information, and expert insights on multimedia security technology used to prove that content is authentic and has not been altered. Illustrating the need for improved content security as the Internet and digital multimedia applications rapidly evolve, this book presents a wealth of everyday protection application examples in fields including multimedia mining and classification, digital watermarking, steganography, and digital forensics. Giving readers an in-depth overview of different asp

Wireless optical network for a home network

Science.gov (United States)

Bouchet, Olivier; Porcon, Pascal; Walewski, Joachim W.; Nerreter, Stefan; Langer, Klaus-Dieter; Fernández, Luz; Vucic, Jelena; Kamalakis, Thomas; Ntogari, Georgia; Neokosmidis, Ioannis; Gueutier, Eric

2010-08-01

During the European collaborative project OMEGA, two optical-wireless prototypes have been developed. The first prototype operates in the near-infrared spectral region and features Giga Ethernet connectivity, a simple transceiver architecture due to the use of on-off keying, a multi-sector transceiver, and an ultra-fast switch for sector-to-sector hand over. This full-duplex system, composed by one base station and one module, transmits data on three meters. The second prototype is a visible-light-communications system based on DMT signal processing and an adapted MAC sublayer. Data rates around to 100 Mb/s at the physical layer are achieved. This broadcast system, composed also by one base station and one module, transmits data up to two meters. In this paper we present the adapted optical wireless media-access-control sublayer protocol for visible-light communications. This protocol accommodates link adaptation from 128 Mb/s to 1024 Mb/s with multi-sector coverage, and half-duplex or full-duplex transmission.

A novel PON based UMTS broadband wireless access network architecture with an algorithm to guarantee end to end QoS

Science.gov (United States)

Sana, Ajaz; Hussain, Shahab; Ali, Mohammed A.; Ahmed, Samir

2007-09-01

In this paper we proposes a novel Passive Optical Network (PON) based broadband wireless access network architecture to provide multimedia services (video telephony, video streaming, mobile TV, mobile emails etc) to mobile users. In the conventional wireless access networks, the base stations (Node B) and Radio Network Controllers (RNC) are connected by point to point T1/E1 lines (Iub interface). The T1/E1 lines are expensive and add up to operating costs. Also the resources (transceivers and T1/E1) are designed for peak hours traffic, so most of the time the dedicated resources are idle and wasted. Further more the T1/E1 lines are not capable of supporting bandwidth (BW) required by next generation wireless multimedia services proposed by High Speed Packet Access (HSPA, Rel.5) for Universal Mobile Telecommunications System (UMTS) and Evolution Data only (EV-DO) for Code Division Multiple Access 2000 (CDMA2000). The proposed PON based back haul can provide Giga bit data rates and Iub interface can be dynamically shared by Node Bs. The BW is dynamically allocated and the unused BW from lightly loaded Node Bs is assigned to heavily loaded Node Bs. We also propose a novel algorithm to provide end to end Quality of Service (QoS) (between RNC and user equipment).The algorithm provides QoS bounds in the wired domain as well as in wireless domain with compensation for wireless link errors. Because of the air interface there can be certain times when the user equipment (UE) is unable to communicate with Node B (usually referred to as link error). Since the link errors are bursty and location dependent. For a proposed approach, the scheduler at the Node B maps priorities and weights for QoS into wireless MAC. The compensations for errored links is provided by the swapping of services between the active users and the user data is divided into flows, with flows allowed to lag or lead. The algorithm guarantees (1)delay and throughput for error-free flows,(2)short term fairness

Multimedia applications in differential services

International Nuclear Information System (INIS)

Mahfooz, S.; Merabti, M.; Pereira, R.

2003-01-01

In this paper we present a mechanism to provide Quality of Service (QoS) guarantees to different multimedia applications that share link bandwidth in IP-based differential services domain. In this mechanism weights are associated with each and to individual users according to their priorities. In order to evaluate the performance of our scheme we conducted simulations. The test data used portray different multimedia applications i.e. MPEG-2, IP telephony. The simulation results obtained show the effectiveness of our scheme for multimedia applications by allocating link share to each multimedia application and minimising end-to-end transmission delay 9Y bringing them in line with the recommended standard acceptable transmission delay for multimedia applications. This paper also presents extension to our proposed Relative Bandwidth Sharing (RES) scheme for differential services. We have identified and highlighted the role of border routers and core routers in differential services domain. Exploring features of Internet Protocol IPv6 in our architecture. (author)

Principles of Multimedia News Systems for Business Applications

Directory of Open Access Journals (Sweden)

Ioan I. ANDONE

2009-01-01

Full Text Available In the past few years considerable demand for business oriented multimedia information systems has developed. A multimedia information system is one that can create, import, integrate, store, retrieve, edit, and delete two or more types of media materials in digital form, such as audio, image, full-motion video, and text information. Multimedia information systems play a central role in many business activities. They represent a very special class complex computing systems. This paper surveys a special type of multimedia information systems: multimedia news systems. Multimedia news systems deal with architectures to manage complex multimedia news databases, online presentation and distribution services or the integration of several existing services to meta-services using intelligent news retrieval engines. The leading presentation platform in multimedia news presentation is news networks providing television services and Internet content distribution. The primary focus is on advanced multimedia news systems infrastructure, document standards, application architecture and principles for multimedia news on the Web that suggest long-term trends in this increasingly important area.

Wireless Distributed Antenna MIMO

DEFF Research Database (Denmark)

2015-01-01

The present disclosure relates to system applications of multicore optical fibers. One embodiment relates to a base transceiver station for a wireless telecommunication system comprising a plurality of antenna units arranged in a MIMO configuration and adapted for transmission and/or reception...... of radio-frequency signals, an optical transmitter in the form of an electro-optic conversion unit for each of said plurality of antenna units, each electro-optic conversion unit adapted for converting an RF signal into an optical signal, a plurality of a single core optical fibers for guiding the optical...

Multimedia and Business Education.

Science.gov (United States)

Klemin, V. Wayne

1993-01-01

Old technology (the computer) coupled with borrowed technology (television, film, and stereo) complemented by multimedia standards from IBM, Apple, and the MPC Council and linked by new software form a new technology called multimedia, being used in education and in business training. (Author/JOW)

Power Control and Coding Formulation for State Estimation with Wireless Sensors

DEFF Research Database (Denmark)

Quevedo, Daniel; Østergaard, Jan; Ahlen, Anders

2014-01-01

efficient communication. In this paper, we examine the role of power control and coding for Kalman filtering over wireless correlated channels. Two estimation architectures are considered; initially, the sensors send their measurements directly to a single gateway (GW). Next, wireless relay nodes provide...... additional links. The GW decides on the coding scheme and the transmitter power levels of the wireless nodes. The decision process is carried out online and adapts to varying channel conditions to improve the tradeoff between state estimation accuracy and energy expenditure. In combination with predictive......Technological advances made wireless sensors cheap and reliable enough to be brought into industrial use. A major challenge arises from the fact that wireless channels introduce random packet dropouts. Power control and coding are key enabling technologies in wireless communications to ensure...

Multimedia programming with pure data

CERN Document Server

Chung, Bryan

2013-01-01

A quick and comprehensive tutorial book for media designers to jump-start interactive multimedia production with computer graphics, digital audio, digital video, and interactivity, using the Pure Data graphical programming environment.An introductory book on multimedia programming for media artists/designers who like to work on interactivity in their projects, digital art/design students who like to learn the first multimedia programming technique, and audio-visual performers who like to customize their performance sets

Research on evaluation techniques for immersive multimedia

Science.gov (United States)

Hashim, Aslinda M.; Romli, Fakaruddin Fahmi; Zainal Osman, Zosipha

2013-03-01

Nowadays Immersive Multimedia covers most usage in tremendous ways, such as healthcare/surgery, military, architecture, art, entertainment, education, business, media, sport, rehabilitation/treatment and training areas. Moreover, the significant of Immersive Multimedia to directly meet the end-users, clients and customers needs for a diversity of feature and purpose is the assembly of multiple elements that drive effective Immersive Multimedia system design, so evaluation techniques is crucial for Immersive Multimedia environments. A brief general idea of virtual environment (VE) context and `realism' concept that formulate the Immersive Multimedia environments is then provided. This is followed by a concise summary of the elements of VE assessment technique that is applied in Immersive Multimedia system design, which outlines the classification space for Immersive Multimedia environments evaluation techniques and gives an overview of the types of results reported. A particular focus is placed on the implications of the Immersive Multimedia environments evaluation techniques in relation to the elements of VE assessment technique, which is the primary purpose of producing this research. The paper will then conclude with an extensive overview of the recommendations emanating from the research.

Scheduling multimedia services in cloud computing environment

Science.gov (United States)

Liu, Yunchang; Li, Chunlin; Luo, Youlong; Shao, Yanling; Zhang, Jing

2018-02-01

Currently, security is a critical factor for multimedia services running in the cloud computing environment. As an effective mechanism, trust can improve security level and mitigate attacks within cloud computing environments. Unfortunately, existing scheduling strategy for multimedia service in the cloud computing environment do not integrate trust mechanism when making scheduling decisions. In this paper, we propose a scheduling scheme for multimedia services in multi clouds. At first, a novel scheduling architecture is presented. Then, We build a trust model including both subjective trust and objective trust to evaluate the trust degree of multimedia service providers. By employing Bayesian theory, the subjective trust degree between multimedia service providers and users is obtained. According to the attributes of QoS, the objective trust degree of multimedia service providers is calculated. Finally, a scheduling algorithm integrating trust of entities is proposed by considering the deadline, cost and trust requirements of multimedia services. The scheduling algorithm heuristically hunts for reasonable resource allocations and satisfies the requirement of trust and meets deadlines for the multimedia services. Detailed simulated experiments demonstrate the effectiveness and feasibility of the proposed trust scheduling scheme.

Generating Multimedia Components for M-Learning

Directory of Open Access Journals (Sweden)

Adriana REVEIU

2009-01-01

Full Text Available The paper proposes a solution to generate template based multimedia components for instruction and learning available both for computer based applications and for mobile devices. The field of research is situated at the intersection of computer science, mobile tools and e-learning and is generically named mobile learning or M-learning. The research goal is to provide access to computer based training resources from any location and to adapt the training content to the specific features of mobile devices, communication environment, users' preferences and users' knowledge. To become important tools in education field, the technical solutions proposed will follow to use the potential of mobile devices.

Forensic hash for multimedia information

Science.gov (United States)

Lu, Wenjun; Varna, Avinash L.; Wu, Min

2010-01-01

Digital multimedia such as images and videos are prevalent on today's internet and cause significant social impact, which can be evidenced by the proliferation of social networking sites with user generated contents. Due to the ease of generating and modifying images and videos, it is critical to establish trustworthiness for online multimedia information. In this paper, we propose novel approaches to perform multimedia forensics using compact side information to reconstruct the processing history of a document. We refer to this as FASHION, standing for Forensic hASH for informatION assurance. Based on the Radon transform and scale space theory, the proposed forensic hash is compact and can effectively estimate the parameters of geometric transforms and detect local tampering that an image may have undergone. Forensic hash is designed to answer a broader range of questions regarding the processing history of multimedia data than the simple binary decision from traditional robust image hashing, and also offers more efficient and accurate forensic analysis than multimedia forensic techniques that do not use any side information.

Presence in the IP Multimedia Subsystem

Directory of Open Access Journals (Sweden)

Ling Lin

2007-01-01

Full Text Available With an ever increasing penetration of Internet Protocol (IP technologies, the wireless industry is evolving the mobile core network towards all-IP network. The IP Multimedia Subsystem (IMS is a standardised Next Generation Network (NGN architectural framework defined by the 3rd Generation Partnership Project (3GPP to bridge the gap between circuit-switched and packet-switched networks and consolidate both sides into on single all-IP network for all services. In this paper, we provide an insight into the limitation of the presence service, one of the fundamental building blocks of the IMS. Our prototype-based study is unique of its kind and helps identifying the factors which limit the scalability of the current version of the presence service (3GPP TS 23.141 version 7.2.0 Release 7 [1], which will in turn dramatically limit the performance of advanced IMS services. We argue that the client-server paradigm behind the current IMS architecture does not suite the requirements of the IMS system, which defies the very purpose of its introduction. We finally elaborate on possible avenues for addressing this problem.

A Comparison of Alternative Distributed Dynamic Cluster Formation Techniques for Industrial Wireless Sensor Networks.

Science.gov (United States)

Gholami, Mohammad; Brennan, Robert W

2016-01-06

In this paper, we investigate alternative distributed clustering techniques for wireless sensor node tracking in an industrial environment. The research builds on extant work on wireless sensor node clustering by reporting on: (1) the development of a novel distributed management approach for tracking mobile nodes in an industrial wireless sensor network; and (2) an objective comparison of alternative cluster management approaches for wireless sensor networks. To perform this comparison, we focus on two main clustering approaches proposed in the literature: pre-defined clusters and ad hoc clusters. These approaches are compared in the context of their reconfigurability: more specifically, we investigate the trade-off between the cost and the effectiveness of competing strategies aimed at adapting to changes in the sensing environment. To support this work, we introduce three new metrics: a cost/efficiency measure, a performance measure, and a resource consumption measure. The results of our experiments show that ad hoc clusters adapt more readily to changes in the sensing environment, but this higher level of adaptability is at the cost of overall efficiency.

Teaching with Interactive Multimedia.

Science.gov (United States)

Hudson, Tim

Based on the idea that anyone who is interested in making entertaining and informative presentations in educational settings is interested in multimedia, this practical guide offers tips for communication (and other) teachers who want to integrate and program interactive multimedia into their courses. The guide suggests that teachers on limited…

Simple Adaptive Single Differential Coherence Detection of BPSK Signals in IEEE 802.15.4 Wireless Sensor Networks.

Science.gov (United States)

Zhang, Gaoyuan; Wen, Hong; Wang, Longye; Xie, Ping; Song, Liang; Tang, Jie; Liao, Runfa

2017-12-26

In this paper, we propose an adaptive single differential coherent detection (SDCD) scheme for the binary phase shift keying (BPSK) signals in IEEE 802.15.4 Wireless Sensor Networks (WSNs). In particular, the residual carrier frequency offset effect (CFOE) for differential detection is adaptively estimated, with only linear operation, according to the changing channel conditions. It was found that the carrier frequency offset (CFO) and chip signal-to-noise ratio (SNR) conditions do not need a priori knowledge. This partly benefits from that the combination of the trigonometric approximation sin - 1 ( x ) ≈ x and a useful assumption, namely, the asymptotic or high chip SNR, is considered for simplification of the full estimation scheme. Simulation results demonstrate that the proposed algorithm can achieve an accurate estimation and the detection performance can completely meet the requirement of the IEEE 802.15.4 standard, although with a little loss of reliability and robustness as compared with the conventional optimal single-symbol detector.

Security Management in a Multimedia System

Science.gov (United States)

Rednic, Emanuil; Toma, Andrei

2009-01-01

In database security, the issue of providing a level of security for multimedia information is getting more and more known. For the moment the security of multimedia information is done through the security of the database itself, in the same way, for all classic and multimedia records. So what is the reason for the creation of a security…

A Low Energy Intelligent Clustering Protocol for Wireless Sensor Network

DEFF Research Database (Denmark)

Li, Qiao; Cui, Lingguo; Zhang, Baihai

2010-01-01

LEACH (low-energy adaptive clustering hierarchy) is a well-known self-organizing, adaptive clustering protocol of wireless sensor networks. However it has some shortcomings when it faces such problems as the cluster construction and energy management. In this paper, LEICP (low energy intelligent...

Adaptive Transcutaneous Power Transfer to Implantable Devices: A State of the Art Review.

Science.gov (United States)

Bocan, Kara N; Sejdić, Ervin

2016-03-18

Wireless energy transfer is a broad research area that has recently become applicable to implantable medical devices. Wireless powering of and communication with implanted devices is possible through wireless transcutaneous energy transfer. However, designing wireless transcutaneous systems is complicated due to the variability of the environment. The focus of this review is on strategies to sense and adapt to environmental variations in wireless transcutaneous systems. Adaptive systems provide the ability to maintain performance in the face of both unpredictability (variation from expected parameters) and variability (changes over time). Current strategies in adaptive (or tunable) systems include sensing relevant metrics to evaluate the function of the system in its environment and adjusting control parameters according to sensed values through the use of tunable components. Some challenges of applying adaptive designs to implantable devices are challenges common to all implantable devices, including size and power reduction on the implant, efficiency of power transfer and safety related to energy absorption in tissue. Challenges specifically associated with adaptation include choosing relevant and accessible parameters to sense and adjust, minimizing the tuning time and complexity of control, utilizing feedback from the implanted device and coordinating adaptation at the transmitter and receiver.

Adaptive Transcutaneous Power Transfer to Implantable Devices: A State of the Art Review

Directory of Open Access Journals (Sweden)

Kara N. Bocan

2016-03-01

Full Text Available Wireless energy transfer is a broad research area that has recently become applicable to implantable medical devices. Wireless powering of and communication with implanted devices is possible through wireless transcutaneous energy transfer. However, designing wireless transcutaneous systems is complicated due to the variability of the environment. The focus of this review is on strategies to sense and adapt to environmental variations in wireless transcutaneous systems. Adaptive systems provide the ability to maintain performance in the face of both unpredictability (variation from expected parameters and variability (changes over time. Current strategies in adaptive (or tunable systems include sensing relevant metrics to evaluate the function of the system in its environment and adjusting control parameters according to sensed values through the use of tunable components. Some challenges of applying adaptive designs to implantable devices are challenges common to all implantable devices, including size and power reduction on the implant, efficiency of power transfer and safety related to energy absorption in tissue. Challenges specifically associated with adaptation include choosing relevant and accessible parameters to sense and adjust, minimizing the tuning time and complexity of control, utilizing feedback from the implanted device and coordinating adaptation at the transmitter and receiver.

Physical and Cross-Layer Security Enhancement and Resource Allocation for Wireless Networks

Science.gov (United States)

Bashar, Muhammad Shafi Al

2011-01-01

In this dissertation, we present novel physical (PHY) and cross-layer design guidelines and resource adaptation algorithms to improve the security and user experience in the future wireless networks. Physical and cross-layer wireless security measures can provide stronger overall security with high efficiency and can also provide better…

PENDEKATAN ESTETIKA PADA DESAIN PESAN MULTIMEDIA PEMBELAJARAN

Directory of Open Access Journals (Sweden)

Moeljadi Pranata

2016-10-01

Full Text Available The development of multimedia design is influenced by various theories such as visual aesthetic principles. Aesthetic principles are used to guide the design process as well as play a role to increase the attractiveness of the message. However, along with the progress  in  computer  graphics,  graphic  design  aesthetic  applications in  multimedia learning  has  led  to  the  concept  of  multimedia  performances entertaining, aesthetic oriented. Additionally, this technology, along with multimedia technology, has expanded the field of professional designing multimedia learning beyond learning profession such as graphic designer profession.

International Conference on Multimedia and Ubiquitous Engineering

CERN Document Server

Chen, Shu-Ching; Gil, Joon-Min; Yen, Neil; Multimedia and Ubiquitous Engineering

2014-01-01

The aims of these proceedings are to provide a complete coverage of the areas outlined, and to bring together researchers from academic and industry to share ideas, challenges, and solutions relating to the multifaceted aspects of this field. New multimedia standards (for example, MPEG-21) facilitate the seamless integration of multiple modalities into interoperable multimedia frameworks, transforming the way people work and interact with multimedia data. These key technologies and multimedia solutions interact and collaborate with each other in increasingly effective ways, contributing to the multimedia revolution and having a significant impact across a wide spectrum of consumer, business, healthcare, education, and governmental domains.

RObust header compression (ROHC) performance for multimedia transmission over 3G/4G wireless networks

DEFF Research Database (Denmark)

Fitzek, Frank; Rein, S.; Seeling, P.

2005-01-01

Robust Header Compression (ROHC) has recently been proposed to reduce the large protocol header overhead when transmitting voice and other continuous meadi over IP based control stacks in wireless networks. In this paper we evaluate the real-time transmission of GSM encoded voice and H. 26L encod...

Battling Latency in Modern Wireless Networks

KAUST Repository

Showail, Ahmad

2018-05-15

Buffer sizing has a tremendous effect on the performance of Wi-Fi based networks. Choosing the right buffer size is challenging due to the dynamic nature of the wireless environment. Over buffering or ‘bufferbloat’ may produce unacceptable endto-end delays. On the other hand, small buffers may limit the performance gains that can be obtained with various IEEE 802.11n/ac enhancements, such as frame aggregation. We propose Wireless Queue Management (WQM), a novel, practical, and lightweight queue management scheme for wireless networks. WQM adapts the buffer size based on the wireless link characteristics and the network load. Furthermore, it accounts for aggregates length when deciding on the optimal buffer size. We evaluate WQM using our 10 nodes wireless testbed. WQM reduces the end-to-end delay by an order of magnitude compared to the default buffer size in Linux while achieving similar network throughput. Also, WQM outperforms state of the art bufferbloat solutions, namely CoDel and PIE. WQM achieves 7× less latency compared to PIE, and 2× compared to CoDel at the cost of 8% drop in goodput in the worst case. Further, WQM improves network fairness as it limits the ability of a single flow to saturate the buffers.

Battling Latency in Modern Wireless Networks

KAUST Repository

Showail, Ahmad; Shihada, Basem

2018-01-01

Buffer sizing has a tremendous effect on the performance of Wi-Fi based networks. Choosing the right buffer size is challenging due to the dynamic nature of the wireless environment. Over buffering or ‘bufferbloat’ may produce unacceptable endto-end delays. On the other hand, small buffers may limit the performance gains that can be obtained with various IEEE 802.11n/ac enhancements, such as frame aggregation. We propose Wireless Queue Management (WQM), a novel, practical, and lightweight queue management scheme for wireless networks. WQM adapts the buffer size based on the wireless link characteristics and the network load. Furthermore, it accounts for aggregates length when deciding on the optimal buffer size. We evaluate WQM using our 10 nodes wireless testbed. WQM reduces the end-to-end delay by an order of magnitude compared to the default buffer size in Linux while achieving similar network throughput. Also, WQM outperforms state of the art bufferbloat solutions, namely CoDel and PIE. WQM achieves 7× less latency compared to PIE, and 2× compared to CoDel at the cost of 8% drop in goodput in the worst case. Further, WQM improves network fairness as it limits the ability of a single flow to saturate the buffers.

Towards an Integrated Solution for Multimedia Communications

OpenAIRE

Mathy, Laurent; Leduc, Guy; Danthine, André; Bonaventure, Olivier

1996-01-01

During the last few years, we have been witnessing tremendous changes in the communication environment. Those changes are not only due to the availability of higher data rates in the communication networks but also to the appearance of new application types such as multimedia applications. After a brief introduction to multimedia communications, we will present the research activities in multimedia we have undertaken during the last few years. They focus on two aspects of multimedia communica...

Real-Time and Secure Wireless Health Monitoring

Science.gov (United States)

Dağtaş, S.; Pekhteryev, G.; Şahinoğlu, Z.; Çam, H.; Challa, N.

2008-01-01

We present a framework for a wireless health monitoring system using wireless networks such as ZigBee. Vital signals are collected and processed using a 3-tiered architecture. The first stage is the mobile device carried on the body that runs a number of wired and wireless probes. This device is also designed to perform some basic processing such as the heart rate and fatal failure detection. At the second stage, further processing is performed by a local server using the raw data transmitted by the mobile device continuously. The raw data is also stored at this server. The processed data as well as the analysis results are then transmitted to the service provider center for diagnostic reviews as well as storage. The main advantages of the proposed framework are (1) the ability to detect signals wirelessly within a body sensor network (BSN), (2) low-power and reliable data transmission through ZigBee network nodes, (3) secure transmission of medical data over BSN, (4) efficient channel allocation for medical data transmission over wireless networks, and (5) optimized analysis of data using an adaptive architecture that maximizes the utility of processing and computational capacity at each platform. PMID:18497866

Multimedia ontology representation and applications

CERN Document Server

Chaudhury, Santanu; Ghosh, Hiranmay

2015-01-01

The result of more than 15 years of collective research, Multimedia Ontology: Representation and Applications provides a theoretical foundation for understanding the nature of media data and the principles involved in its interpretation. The book presents a unified approach to recent advances in multimedia and explains how a multimedia ontology can fill the semantic gap between concepts and the media world. It relays real-life examples of implementations in different domains to illustrate how this gap can be filled.The book contains information that helps with building semantic, content-based

Wireless local area network for the dental office.

Science.gov (United States)

Mupparapu, Muralidhar

2004-01-01

Dental offices are no exception to the implementation of new and advanced technology, especially if it enhances productivity. In a rapidly transforming digital world, wireless technology has a special place, as it has truly "retired the wire" and contributed to the ease and efficient access to patient data and other software-based applications for diagnosis and treatment. If the office or the clinic is networked, access to patient management software, imaging software and treatment planning tools is enhanced. Access will be further enhanced and unrestricted if the entire network is wireless. As with any new, emerging technology, there will be issues that should be kept in mind before adapting to the wireless environment. Foremost is the network security involved in the installation and use of these wireless networks. This short, technical manuscript deals with standards and choices in wireless technology currently available for implementation within a dental office. The benefits of each network security protocol available to protect patient data and boost the efficiency of a modern dental office are discussed.

Discover the pythagorean theorem using interactive multimedia learning

Science.gov (United States)

Adhitama, I.; Sujadi, I.; Pramudya, I.

2018-04-01

In learning process students are required to play an active role in learning. They do not just accept the concept directly from teachers, but also build their own knowledge so that the learning process becomes more meaningful. Based on the observation, when learning Pythagorean theorem, students got difficulty on determining hypotenuse. One of the solution to solve this problem is using an interactive multimedia learning. This article aims to discuss the interactive multimedia as learning media for students. This was a Research and Development (R&D) by using ADDIE model of development. The results obtained was multimedia which was developed proper for students as learning media. Besides, on Phytagorian theorem learning activity we also compare Discovery Learning (DL) model with interactive multimedia and DL without interactive multimedia, and obtained that DL with interactive gave positive effect better than DL without interactive multimedia. It was also obtainde that interactive multimedia can attract and increase the interest ot the students on learning math. Therefore, the use of interactive multimedia on DL procees can improve student learning achievement.

The future is 'ambient'

Science.gov (United States)

Lugmayr, Artur

2006-02-01

The research field of ambient media starts to spread rapidly and first applications for consumer homes are on the way. Ambient media is the logical continuation of research around media. Media has been evolving from old media (e.g. print media), to integrated presentation in one form (multimedia - or new media), to generating a synthetic world (virtual reality), to the natural environment is the user-interface (ambient media), and will be evolving towards real/synthetic undistinguishable media (bio-media or bio-multimedia). After the IT bubble was bursting, multimedia was lacking a vision of potential future scenarios and applications. Within this research paper the potentials, applications, and market available solutions of mobile ambient multimedia are studied. The different features of ambient mobile multimedia are manifold and include wearable computers, adaptive software, context awareness, ubiquitous computers, middleware, and wireless networks. The paper especially focuses on algorithms and methods that can be utilized to realize modern mobile ambient systems.

DEA Multi-Media Drug Library

Science.gov (United States)

... Releases Speeches and Testimony Major Operations Multi-Media Library Micrograms Legislative & Legal Resources Events Social Media Directory ... Envío de información confidencial Press Room » Multi-Media Library IMAGE GALLERY Drug Photos Amphetamines/Stimulants K2/Spice ...

A Framework for a Distributed and Adaptive Query Processing Engine for Wireless Sensor Networks

NARCIS (Netherlands)

Chatterjea, Supriyo; Honda, S; Iwaoka, H; van Hoesel, L.F.W.; Havinga, Paul J.M.

Wireless sensor networks (WSNs) are formed of tiny, highly energy-constrained sensor nodes that are equipped with wireless transceivers and can be used primarily in environmental monitoring applications. The nodes communicate with one another by autonomously creating ad-hoc multihop networks which

Multimedia Search Engines : Concept, Performance, and Types

OpenAIRE

Sayed Rabeh Sayed

2005-01-01

A Research about multimedia search engines, it starts with definition of search engines at general and multimedia search engines, then explains how they work, and divided them into: Video search engines, Images search engines, and Audio search engines. Finally, it reviews a samples to multimedia search engines.

A Framework for Narration and Learning in Educational Multimedia

DEFF Research Database (Denmark)

Mosegaard, Jesper; Bennedsen, Jens

2006-01-01

In this article we describe a multimedia adventure game framework for a learningenvironment to support the teaching and learning of introductory programming. In theframework we have conceptualized two important aspects of such an environment: narrationand learning topics. We describe the interplay...... between these aspects and how the frameworkutilizes this to adapt the learning process to the individual student. The motivation for theseparation is to help the teacher balance the two main driving forces of an edutainmentproduct: entertainment and learning. It is the responsibility of the teacher...

Flexible Adaptation in Cognitive Radios

CERN Document Server

Li, Shujun

2013-01-01

This book provides an introduction to software-defined radio and cognitive radio, along with methodologies for applying knowledge representation, semantic web, logic reasoning and artificial intelligence to cognitive radio, enabling autonomous adaptation and flexible signaling. Readers from the wireless communications and software-defined radio communities will use this book as a reference to extend software-defined radio to cognitive radio, using the semantic technology described. Readers with a background in semantic web and artificial intelligence will find in this book the application of semantic web and artificial intelligence technologies to wireless communications. For readers in networks and network management, this book presents a new approach to enable interoperability, collaborative optimization and flexible adaptation of network components. Provides a comprehensive ontology covering the core concepts of wireless communications using a formal language; Presents the technical realization of using a ...

Cognitive Architectures for Multimedia Learning

Science.gov (United States)

Reed, Stephen K.

2006-01-01

This article provides a tutorial overview of cognitive architectures that can form a theoretical foundation for designing multimedia instruction. Cognitive architectures include a description of memory stores, memory codes, and cognitive operations. Architectures that are relevant to multimedia learning include Paivio's dual coding theory,…

Multimedia Modules for Electromagnetics Education.

Science.gov (United States)

De Los Santos Vidal, Oriol; Iskander, Magdy F.

1997-01-01

Multimedia technology is an invaluable teaching and learning resource. One advantage of technology based education is the ability to combine practical applications, visualization of complex mathematical and abstract subjects, virtual labs, and guided use of simulation software. This article describes several multimedia tutorials for…

Multimedia and Textual Reading Comprehension: Multimedia as Personal Learning Environment’s Enriching Format

Directory of Open Access Journals (Sweden)

Jose Daniel García Martínez

2017-01-01

Full Text Available In this article we will discuss part of a piece of research that was conducted with two 4ESO groups. Textual learning is opposed to multimedia learning within the context of PLE’s (Personal Learning Environment reading tools and strategies. In the research an analysis was made of whether it would be possible to improve the reading process through multimedia over a school term in two different aspects; one evolutionary with six classroom exercises and one evaluation with a final exercise. Concretely, this article states the number of question mistakes that the students made. The data indicates that there is a better evolution in students that performed the multimedia dynamic, although there are not any relevant differences in the final evaluation.

Enhancements of LEACH Algorithm for Wireless Networks: A Review

Directory of Open Access Journals (Sweden)

M. Madheswaran

2013-12-01

Full Text Available Low Energy Adaptive Clustering Hierarchy (LEACH protocol is the first hierarchical cluster based routing protocol successfully used in the Wireless Sensor Networks (WSN. In this paper, various enhancements used in the original LEACH protocol are examined. The basic operations, advantages and limitations of the modified LEACH algorithms are compared to identify the research issues to be solved and to give the suggestions for the future proposed routing algorithms of wireless networks based on LEACH routing algorithm.

Survey of a wireless NDT service for a nuclear piping wall thinning defect

International Nuclear Information System (INIS)

Choi, Yoo Rark; Lee, Jae Cheol

2008-01-01

The wireless sensor network has been issued for several years. The nuclear power plants all around world have adapted many kinds of sensor technologies for inspections and diagnostics of main instruments. Even though wireless sensor is more useful than wired sensor, wireless sensor based applications haven't been used in nuclear power plants because of the authorization of a jamming, an electromagnetic interference and so on. A wireless sensor uses a battery for its operations, but this battery can't be used for a long haul. It causes a battery change problem. There aren't any wireless sensor based NDT for a piping wall thinning part. We will describe a method of how to develop it in this paper

Adaptive Bio-Inspired Wireless Network Routing for Planetary Surface Exploration

Science.gov (United States)

Alena, Richard I.; Lee, Charles

2004-01-01

Wireless mobile networks suffer connectivity loss when used in a terrain that has hills, and valleys when line of sight is interrupted or range is exceeded. To resolve this problem and achieve acceptable network performance, we have designed an adaptive, configurable, hybrid system to automatically route network packets along the best path between multiple geographically dispersed modules. This is very useful in planetary surface exploration, especially for ad-hoc mobile networks, where computational devices take an active part in creating a network infrastructure, and can actually be used to route data dynamically and even store data for later transmission between networks. Using inspiration from biological systems, this research proposes to use ant trail algorithms with multi-layered information maps (topographic maps, RF coverage maps) to determine the best route through ad-hoc network at real time. The determination of best route is a complex one, and requires research into the appropriate metrics, best method to identify the best path, optimizing traffic capacity, network performance, reliability, processing capabilities and cost. Real ants are capable of finding the shortest path from their nest to a food source without visual sensing through the use of pheromones. They are also able to adapt to changes in the environment using subtle clues. To use ant trail algorithms, we need to define the probability function. The artificial ant is, in this case, a software agent that moves from node to node on a network graph. The function to calculate the fitness (evaluate the better path) includes: length of the network edge, the coverage index, topology graph index, and pheromone trail left behind by other ant agents. Each agent modifies the environment in two different ways: 1) Local trail updating: As the ant moves between nodes it updates the amount of pheromone on the edge; and 2) Global trail updating: When all ants have completed a tour the ant that found the

Multimedia Principle in Teaching Lessons

Science.gov (United States)

Kari Jabbour, Khayrazad

2012-01-01

Multimedia learning principle occurs when we create mental representations from combining text and relevant graphics into lessons. This article discusses the learning advantages that result from adding multimedia learning principle into instructions; and how to select graphics that support learning. There is a balance that instructional designers…

Multi-Resolution Multimedia QoE Models for IPTV Applications

Directory of Open Access Journals (Sweden)

Prasad Calyam

2012-01-01

Full Text Available Internet television (IPTV is rapidly gaining popularity and is being widely deployed in content delivery networks on the Internet. In order to proactively deliver optimum user quality of experience (QoE for IPTV, service providers need to identify network bottlenecks in real time. In this paper, we develop psycho-acoustic-visual models that can predict user QoE of multimedia applications in real time based on online network status measurements. Our models are neural network based and cater to multi-resolution IPTV applications that include QCIF, QVGA, SD, and HD resolutions encoded using popular audio and video codec combinations. On the network side, our models account for jitter and loss levels, as well as router queuing disciplines: packet-ordered and time-ordered FIFO. We evaluate the performance of our multi-resolution multimedia QoE models in terms of prediction characteristics, accuracy, speed, and consistency. Our evaluation results demonstrate that the models are pertinent for real-time QoE monitoring and resource adaptation in IPTV content delivery networks.

Low latency adaptive streaming of HD H.264 video over 802.11 wireless networks with cross-layer feedback

Science.gov (United States)

Patti, Andrew; Tan, Wai-tian; Shen, Bo

2007-09-01

Streaming video in consumer homes over wireless IEEE 802.11 networks is becoming commonplace. Wireless 802.11 networks pose unique difficulties for streaming high definition (HD), low latency video due to their error-prone physical layer and media access procedures which were not designed for real-time traffic. HD video streaming, even with sophisticated H.264 encoding, is particularly challenging due to the large number of packet fragments per slice. Cross-layer design strategies have been proposed to address the issues of video streaming over 802.11. These designs increase streaming robustness by imposing some degree of monitoring and control over 802.11 parameters from application level, or by making the 802.11 layer media-aware. Important contributions are made, but none of the existing approaches directly take the 802.11 queuing into account. In this paper we take a different approach and propose a cross-layer design allowing direct, expedient control over the wireless packet queue, while obtaining timely feedback on transmission status for each packet in a media flow. This method can be fully implemented on a media sender with no explicit support or changes required to the media client. We assume that due to congestion or deteriorating signal-to-noise levels, the available throughput may drop substantially for extended periods of time, and thus propose video source adaptation methods that allow matching the bit-rate to available throughput. A particular H.264 slice encoding is presented to enable seamless stream switching between streams at multiple bit-rates, and we explore using new computationally efficient transcoding methods when only a high bit-rate stream is available.

Standards of Multimedia Graphic Design in Education

Science.gov (United States)

Aldalalah, Osamah Ahmad; Ababneh, Ziad Waleed Mohamed

2015-01-01

This study aims to determine Standards of Multimedia Graphic Design in Education through the analysis of the theoretical basis and previous studies related to this subject. This study has identified the list of standards of Multimedia, Graphic Design, each of which has a set indicator through which the quality of Multimedia can be evaluated in…

A Survey on Sensor Coverage and Visual Data Capturing/Processing/Transmission in Wireless Visual Sensor Networks

Directory of Open Access Journals (Sweden)

Florence G. H. Yap

2014-02-01

Full Text Available Wireless Visual Sensor Networks (WVSNs where camera-equipped sensor nodes can capture, process and transmit image/video information have become an important new research area. As compared to the traditional wireless sensor networks (WSNs that can only transmit scalar information (e.g., temperature, the visual data in WVSNs enable much wider applications, such as visual security surveillance and visual wildlife monitoring. However, as compared to the scalar data in WSNs, visual data is much bigger and more complicated so intelligent schemes are required to capture/process/ transmit visual data in limited resources (hardware capability and bandwidth WVSNs. WVSNs introduce new multi-disciplinary research opportunities of topics that include visual sensor hardware, image and multimedia capture and processing, wireless communication and networking. In this paper, we survey existing research efforts on the visual sensor hardware, visual sensor coverage/deployment, and visual data capture/ processing/transmission issues in WVSNs. We conclude that WVSN research is still in an early age and there are still many open issues that have not been fully addressed. More new novel multi-disciplinary, cross-layered, distributed and collaborative solutions should be devised to tackle these challenging issues in WVSNs.

System using data compression and hashing adapted for use for multimedia encryption

Science.gov (United States)

Coffland, Douglas R [Livermore, CA

2011-07-12

A system and method is disclosed for multimedia encryption. Within the system of the present invention, a data compression module receives and compresses a media signal into a compressed data stream. A data acquisition module receives and selects a set of data from the compressed data stream. And, a hashing module receives and hashes the set of data into a keyword. The method of the present invention includes the steps of compressing a media signal into a compressed data stream; selecting a set of data from the compressed data stream; and hashing the set of data into a keyword.

8th International KES Conference on Intelligent Interactive Multimedia : Systems and Services

CERN Document Server

Howlett, Robert; Jain, Lakhmi; Gallo, Luigi; Pietro, Giuseppe

2015-01-01

Intelligent interactive multimedia systems and services will be ever more important in computer systems. Nowadays, computers are widespread and computer users range from highly qualified scientists to non-computer expert professionals. Therefore, designing dynamic personalization and adaptivity methods to store, process, transmit and retrieve information is critical for matching the technological progress with the consumer needs. This book contains the contributions presented at the eighth international KES conference on Intelligent Interactive Multimedia: Systems and Services, which took place in Sorrento, Italy, June 17-19, 2015. It contains 33 peer-reviewed scientific contributions that focus on issues ranging from intelligent image or video storage, retrieval, transmission and analysis to knowledge-based technologies, from advanced information technology architectures for video processing and transmission to advanced functionalities of information and knowledge-based services. We believe that this book w...

Adaptive Multipath Key Reinforcement for Energy Harvesting Wireless Sensor Networks

DEFF Research Database (Denmark)

Di Mauro, Alessio; Dragoni, Nicola

2015-01-01

Energy Harvesting - Wireless Sensor Networks (EH-WSNs) constitute systems of networked sensing nodes that are capable of extracting energy from the environment and that use the harvested energy to operate in a sustainable state. Sustainability, seen as design goal, has a significant impact...

Error and Congestion Resilient Video Streaming over Broadband Wireless

Directory of Open Access Journals (Sweden)

Laith Al-Jobouri

2015-04-01

Full Text Available In this paper, error resilience is achieved by adaptive, application-layer rateless channel coding, which is used to protect H.264/Advanced Video Coding (AVC codec data-partitioned videos. A packetization strategy is an effective tool to control error rates and, in the paper, source-coded data partitioning serves to allocate smaller packets to more important compressed video data. The scheme for doing this is applied to real-time streaming across a broadband wireless link. The advantages of rateless code rate adaptivity are then demonstrated in the paper. Because the data partitions of a video slice are each assigned to different network packets, in congestion-prone wireless networks the increased number of packets per slice and their size disparity may increase the packet loss rate from buffer overflows. As a form of congestion resilience, this paper recommends packet-size dependent scheduling as a relatively simple way of alleviating the buffer-overflow problem arising from data-partitioned packets. The paper also contributes an analysis of data partitioning and packet sizes as a prelude to considering scheduling regimes. The combination of adaptive channel coding and prioritized packetization for error resilience with packet-size dependent packet scheduling results in a robust streaming scheme specialized for broadband wireless and real-time streaming applications such as video conferencing, video telephony, and telemedicine.

Effect of student engagement on multimedia-assisted instruction

Directory of Open Access Journals (Sweden)

Hsiu-Ping Yueh

2012-09-01

Full Text Available This study applied multimedia in a general engineering and technology course in Taiwan and evaluated the effectiveness of multimedia-assisted instruction and learning. The course presented trends in technological development and the achievements of Taiwanese industries and research institutes from a historical perspective, and overviewed the technology industries and industrial transformation development in Taiwan. The course units adopted multimedia to support class teaching and student learning, and a survey was conducted to collect students’ attitudes and perception toward multimedia-assisted instruction and learning in the course. Research data were collected from 45 male and 9 female students with varied academic and cultural backgrounds. Results showed that multimedia videos help raise students’ awareness of learning issues, improve their understanding of content, and increase the depth of their learning. Almost all students liked the approach of using multimedia to assist teaching and learning, preferring this approach over traditional lecture-based instruction. They also would recommend this course to their peers. This study also found that the degree of students’ engagement caused variance in the students’ perception of multimedia helpfulness in assisting their learning. Finally, this study further proposes suggestions in both design and research on applications of multimedia-enhanced learning in engineering and technology education.

3rd International Conference on Multimedia Technology

CERN Document Server

Yang, Jian; Jiao, Feng

2014-01-01

Proceedings of the 3rd International Conference on Multimedia Technology (ICMT2013) focuses on both the theory and applications of multimedia technology. The recent advances, new research findings and applications in the fields of theoretical, experimental and applied image & video processing and multimedia technology presented at the conference are brought together in this book. It will serve as a valuable reference for scientists and engineers working in multimedia and related fields. Prof. Aly A. Farag works at the University of Louisville, USA; Prof. Jian Yang works at Tsinghua University, China; Dr. Feng Jiao works at Nanjing University of Information Science & Technology, China.

Optimizing the efficacy of multimedia consumer health information.

Science.gov (United States)

Monkman, Helen; Kushniruk, Andre W

2015-01-01

Using two or more communication methods (e.g., text, narration, pictures, animation, video) is known as multimedia. Multimedia has been used in a broad range of domains. Not surprisingly, multimedia is gaining popularity in the field of consumer health information as its benefits are being recognized. However, there is a large body of evidence in the cognitive literature that could be used to inform and optimize multimedia presentation of consumer health information. This paper outlines the Cognitive Theory of Multimedia Learning (CTML) and presents the application of this model for consumer health informatics. The CTML is a valuable resource for the development and revision of consumer health information to optimize its efficacy. Current research on multimedia and consumer health information is described. Finally, the outstanding opportunities to leverage the CTML for consumer health information are discussed.

Towards Controlling Latency in Wireless Networks

KAUST Repository

Bouacida, Nader

2017-04-24

, we propose a novel design called “LearnQueue” based on reinforcement learning that can effectively control the latency in wireless networks. LearnQueue adapts quickly and intelligently to changes in the wireless environment using a sophisticated reward structure. Testbed results prove that LearnQueue can guarantee low latency while preserving throughput.

A preliminary study of current multimedia information technology

Energy Technology Data Exchange (ETDEWEB)

Lee, J.C.

1997-03-01

This paper surveys more than 70 articles published in the IEEE Multimedia journal and other journals. The survey summarizes aspects of multimedia information technology and categorizes application areas of multimedia information technology and interesting research areas related to it.

Multimedia category preferences of working engineers

Science.gov (United States)

Baukal, Charles E.; Ausburn, Lynna J.

2016-09-01

Many have argued for the importance of continuing engineering education (CEE), but relatively few recommendations were found in the literature for how to use multimedia technologies to deliver it most effectively. The study reported here addressed this gap by investigating the multimedia category preferences of working engineers. Four categories of multimedia, with two types in each category, were studied: verbal (text and narration), static graphics (drawing and photograph), dynamic non-interactive graphics (animation and video), and dynamic interactive graphics (simulated virtual reality (VR) and photo-real VR). The results showed that working engineers strongly preferred text over narration and somewhat preferred drawing over photograph, animation over video, and simulated VR over photo-real VR. These results suggest that a variety of multimedia types should be used in the instructional design of CEE content.

New Visions of Reality: Multimedia and Education.

Science.gov (United States)

Ambron, Sueann

1986-01-01

Multimedia is a powerful tool that will change both the way we look at knowledge and our vision of reality, as well as our educational system and the business world. Multimedia as used here refers to the innovation of mixing text, audio, and video through the use of a computer. Not only will there be new products emerging from multimedia uses, but…

DOES MULTIMEDIA THEORY APPLY TO ALL STUDENTS? THE IMPACT OF MULTIMEDIA PRESENTATIONS ON SCIENCE LEARNING

Directory of Open Access Journals (Sweden)

Peter G. Schrader

2016-01-01

Full Text Available User You are logged in as... mocak My Profile Log Out Log Out as User Journal Content Search Search Scope Browse By Issue By Author By Title Indexing/Abstracting -Doaj -Google Scholar -J Gate/Informatics -Ulrich's Under review by: -Ebsco -Journal Seek -info BASE INDEX -ERIC -Ulakbim/tr index Article Tools Abstract Print this article Indexing metadata How to cite item Finding References Review policy Email this article Email the author Related Items Show all The fourth issue of Journal of Learning and Teaching in Digital Age(JOLTIDA has been published. Editorial Board Open Journal Systems Journal Help Notifications View (564 new Manage Information For Readers For Authors For Librarians Creative Commons License Font Size Make font size smaller Make font size default Make font size larger Home About User Home Search Current Archives Announcements Home > Vol 1, No 1 (2016 > Schrader  DOES MULTIMEDIA THEORY APPLY TO ALL STUDENTS? THE IMPACT OF MULTIMEDIA PRESENTATIONS ON SCIENCE LEARNING Peter G. Schrader University of Nevada Las Vegas, USA pg.schrader@unlv.edu Eric E. Rapp ericrapp@icloud.com ABSTRACT In K-12 school settings in the United States, there is a preponderance of information delivered via multimedia to students everyday (e.g., visual aids found in science textbooks, electronic tablets, streamed video content, web pages, animations, and PowerPoint presentations. The cognitive theory of multimedia learning (CTML outlines numerous principles associated with learning from and with multimedia (Mayer, Hegarty, Mayer, & Cambell, 2005. However, the bulk of the research like the CTML has been conducted using college age students (Jones, 2010; McTigue, 2009. There is ample evidence that college age students and younger students exhibit numerous and important differences when learning from multimedia content (Hannus & Hyona, 1999; McTique, 2009; Moreno, 2007; Van Parreren, 1983. As a result, the objective of the current study is to examine the

Cognitive Synergy in Multimedia Learning

Science.gov (United States)

Kim, Daesang; Kim, Dong-Joong; Whang, Woo-Hyung

2013-01-01

The main focus of our study was to investigate multimedia effects that had different results from the findings of existing multimedia learning studies. First, we describe and summarize three experimental studies we conducted from 2006 to 2010. Then we analyze our findings to explore learner characteristics that may impact the cognitive processes…

Using Multimedia for E-Learning

Science.gov (United States)

Mayer, R. E.

2017-01-01

This paper reviews 12 research-based principles for how to design computer-based multimedia instructional materials to promote academic learning, starting with the multimedia principle (yielding a median effect size of d = 1.67 based on five experimental comparisons), which holds that people learn better from computer-based instruction containing…

For Effective Use of Multimedia in Education, Teachers Must Develop Their Own Educational Multimedia Applications

Science.gov (United States)

Babiker, Mohd. Elmagzoub A.

2015-01-01

This paper makes the strong claim that for multimedia to have any significant effect on education, the educational multimedia applications must be designed by the teachers of those classes. The arguments supporting this claim are presented in the headlines: curriculum, software, hardware and evaluation. The paper begins with an introduction which…

An energy-efficient adaptive sampling scheme for wireless sensor networks

NARCIS (Netherlands)

Masoum, Alireza; Meratnia, Nirvana; Havinga, Paul J.M.

2013-01-01

Wireless sensor networks are new monitoring platforms. To cope with their resource constraints, in terms of energy and bandwidth, spatial and temporal correlation in sensor data can be exploited to find an optimal sampling strategy to reduce number of sampling nodes and/or sampling frequencies while

Adaptive Information Access on Multiple Applications Support Wireless Sensor Networks

DEFF Research Database (Denmark)

Tobgay, Sonam; Olsen, Rasmus Løvenstein; Prasad, Ramjee

2014-01-01

information is challenged by dynamic nature of information elements. These challenges are more prominent in case of wireless sensor network (WSN) applications, as the information that the sensor node collects are mostly dynamic in nature (say, temperature). Therefore, it is likely that there can be a mismatch...

Adaptive Information Access in Multiple Applications Support Wireless Sensor Network

DEFF Research Database (Denmark)

Tobgay, Sonam; Olsen, Rasmus Løvenstein; Prasad, Ramjee

2012-01-01

Nowadays, due to wide applicability of Wireless Sensor Network (WSN) added by the low cost sensor devices, its popularity among the researchers and industrialists are very much visible. A substantial amount of works can be seen in the literature on WSN which are mainly focused on application...

Aquatic Exposure Predictions of Insecticide Field Concentrations Using a Multimedia Mass-Balance Model.

Science.gov (United States)

Knäbel, Anja; Scheringer, Martin; Stehle, Sebastian; Schulz, Ralf

2016-04-05

Highly complex process-driven mechanistic fate and transport models and multimedia mass balance models can be used for the exposure prediction of pesticides in different environmental compartments. Generally, both types of models differ in spatial and temporal resolution. Process-driven mechanistic fate models are very complex, and calculations are time-intensive. This type of model is currently used within the European regulatory pesticide registration (FOCUS). Multimedia mass-balance models require fewer input parameters to calculate concentration ranges and the partitioning between different environmental media. In this study, we used the fugacity-based small-region model (SRM) to calculate predicted environmental concentrations (PEC) for 466 cases of insecticide field concentrations measured in European surface waters. We were able to show that the PECs of the multimedia model are more protective in comparison to FOCUS. In addition, our results show that the multimedia model results have a higher predictive power to simulate varying field concentrations at a higher level of field relevance. The adaptation of the model scenario to actual field conditions suggests that the performance of the SRM increases when worst-case conditions are replaced by real field data. Therefore, this study shows that a less complex modeling approach than that used in the regulatory risk assessment exhibits a higher level of protectiveness and predictiveness and that there is a need to develop and evaluate new ecologically relevant scenarios in the context of pesticide exposure modeling.

A wireless sensor enabled by wireless power.

Science.gov (United States)

Lee, Da-Sheng; Liu, Yu-Hong; Lin, Chii-Ruey

2012-11-22

Through harvesting energy by wireless charging and delivering data by wireless communication, this study proposes the concept of a wireless sensor enabled by wireless power (WPWS) and reports the fabrication of a prototype for functional tests. One WPWS node consists of wireless power module and sensor module with different chip-type sensors. Its main feature is the dual antenna structure. Following RFID system architecture, a power harvesting antenna was designed to gather power from a standard reader working in the 915 MHz band. Referring to the Modbus protocol, the other wireless communication antenna was integrated on a node to send sensor data in parallel. The dual antenna structure integrates both the advantages of an RFID system and a wireless sensor. Using a standard UHF RFID reader, WPWS can be enabled in a distributed area with a diameter up to 4 m. Working status is similar to that of a passive tag, except that a tag can only be queried statically, while the WPWS can send dynamic data from the sensors. The function is the same as a wireless sensor node. Different WPWSs equipped with temperature and humidity, optical and airflow velocity sensors are tested in this study. All sensors can send back detection data within 8 s. The accuracy is within 8% deviation compared with laboratory equipment. A wireless sensor network enabled by wireless power should be a totally wireless sensor network using WPWS. However, distributed WPWSs only can form a star topology, the simplest topology for constructing a sensor network. Because of shielding effects, it is difficult to apply other complex topologies. Despite this limitation, WPWS still can be used to extend sensor network applications in hazardous environments. Further research is needed to improve WPWS to realize a totally wireless sensor network.

Interference-Aware Spectrum Sharing Techniques for Next Generation Wireless Networks

KAUST Repository

Qaraqe, Marwa Khalid

2011-11-20

Background: Reliable high-speed data communication that supports multimedia application for both indoor and outdoor mobile users is a fundamental requirement for next generation wireless networks and requires a dense deployment of physically coexisting network architectures. Due to the limited spectrum availability, a novel interference-aware spectrum-sharing concept is introduced where networks that suffer from congested spectrums (secondary-networks) are allowed to share the spectrum with other networks with available spectrum (primary-networks) under the condition that limited interference occurs to primary networks. Objective: Multiple-antenna and adaptive rate can be utilized as a power-efficient technique for improving the data rate of the secondary link while satisfying the interference constraint of the primary link by allowing the secondary user to adapt its transmitting antenna, power, and rate according to the channel state information. Methods: Two adaptive schemes are proposed using multiple-antenna transmit diversity and adaptive modulation in order to increase the spectral-efficiency of the secondary link while maintaining minimum interference with the primary. Both the switching efficient scheme (SES) and bandwidth efficient scheme (BES) use the scan-and-wait combining antenna technique (SWC) where there is a secondary transmission only when a branch with an acceptable performance is found; else the data is buffered. Results: In both these schemes the constellation size and selected transmit branch are determined to minimized the average number of switches and achieve the highest spectral efficiency given a minimum bit-error-rate (BER), fading conditions, and peak interference constraint. For delayed sensitive applications, two schemes using power control are used: SES-PC and BES-PC. In these schemes the secondary transmitter sends data using a nominal power level, which is optimized to minimize the average delay. Several numerical examples show

A Cross-Layer Approach in Sensing and Resource Allocation for Multimedia Transmission over Cognitive UWB Networks

Directory of Open Access Journals (Sweden)

Lo ACC

2010-01-01

Full Text Available We propose an MAC centric cross-layer approach to address the problem of multimedia transmission over cognitive Ultra Wideband (C-UWB networks. Several fundamental design issues, which are related to application (APP, medium access control (MAC, and physical (PHY layer, are discussed. Although substantial research has been carried out in the PHY layer perspective of cognitive radio system, this paper attempts to extend the existing research paradigm to MAC and APP layers, which can be considered as premature at this time. This paper proposed a cross-layer design that is aware of (a UWB wireless channel conditions, (b time slot allocations at the MAC layer, and (c MPEG-4 video at the APP layer. Two cooperative sensing mechanisms, namely, AND and OR, are analyzed in terms of probability of detection ( , probability of false alarm ( , and the required sensing period. Then, the impact of sensing scheduling to the MPEG-4 video transmission over wireless cognitive UWB networks is observed. In addition, we also proposed the packet reception rate- (PRR- based resource allocation scheme that is aware of the channel condition, target PRR, and queue status.

36 CFR 1194.24 - Video and multimedia products.

Science.gov (United States)

2010-07-01

... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Video and multimedia products... Video and multimedia products. (a) All analog television displays 13 inches and larger, and computer... training and informational video and multimedia productions which support the agency's mission, regardless...

Optimization of Multimedia English Teaching in Context Creation

Science.gov (United States)

Yang, Weiyan; Fang, Fan

2008-01-01

Using multimedia to create a context to teach English has its unique advantages. This paper explores the characteristics of multimedia and integrates how to use multimedia to optimize the context of English teaching as its purpose. In this paper, eight principles, specifically Systematization, Authenticity, Appropriateness, Interactivity,…

Group Coordination Support in Networked Multimedia Systems

National Research Council Canada - National Science Library

Dommel, Hans-Peter

1999-01-01

.... In this dissertation, we address network control and coordination functions to orchestrate synchronous multimedia groupwork, establishing a sharing discipline on multimedia resources and guaranteeing...

Performance Analysis of Rayleigh Fading and Cochannel Interference in Wireless Communication

National Research Council Canada - National Science Library

Gao, Chunjun

2000-01-01

...) performance of adaptive arrays for wireless communications over fading channels in the presence of cochannel interference, particularly the case when the number of interference sources exceeds...

Operating-System Support for Distributed Multimedia

NARCIS (Netherlands)

Mullender, Sape J.; Leslie, Ian M.; McAuley, Derek

1994-01-01

Multimedia applications place new demands upon processors, networks and operating systems. While some network designers, through ATM for example, have considered revolutionary approaches to supporting multimedia, the same cannot be said for operating systems designers. Most work is evolutionary in

Multimedia Security System for Security and Medical Applications

Science.gov (United States)

Zhou, Yicong

2010-01-01

This dissertation introduces a new multimedia security system for the performance of object recognition and multimedia encryption in security and medical applications. The system embeds an enhancement and multimedia encryption process into the traditional recognition system in order to improve the efficiency and accuracy of object detection and…

Multicast Services of QoS-Aware Active Queue Management over IP Multimedia Applications

Science.gov (United States)

Hwang, I.-Shyan; Hwang, Bor-Jiunn; Chang, Pen-Ming

2010-10-01

Recently, the multimedia services such as IPTV, video conference emerges to be the main traffic source. When UDP coexists with TCP, it induces not only congestion collapse but also unfairness problem. In this paper, a new Active Queue Management (AQM) algorithm, called Traffic Sensitive Active Queue Management (TSAQM), is proposed for providing multimedia services. The TSAQM comprise Dynamic Weight Allocate Scheme (DWAS) and Service Guarantee Scheme (SGS), the purpose of DWAS is to allocate resource with fairness and high end-user utility, and the purpose of SGS is to determine the satisfactory threshold (TH) and threshold region (TR). Several objectives of this proposed scheme include achieving high end-user utility for video service, considering the multicast as well as unicast proprieties to meet inter-class fairness and achieving the QoS requirement by adjusting the thresholds adaptively based on traffic situations.

A Multimedia Publishing Center from Scratch (and Scavenge).

Science.gov (United States)

D'Ignazio, Fred

1995-01-01

Provides guidance for turning the library media center into a place where students can use multimedia tools for research, authoring, and publishing. Sidebars include: a multimedia club sample student contract, a component list for a multimedia workstation starter kit, a checklist for planning and assembling mini-centers, and a sample multimedia…

Optic Nerve Stimulation System with Adaptive Wireless Powering and Data Telemetry

Directory of Open Access Journals (Sweden)

Xing Li

2017-12-01

Full Text Available To treat retinal degenerative diseases, a transcorneal electrical stimulation-based system is proposed, which consists of an eye implant and an external component. The eye implant is wirelessly powered and controlled by the external component to generate the required bi-polar current pattern for transcorneal stimulation with an amplitude range of 5 μA to 320 μA, a frequency range of 10 Hz to 160 Hz and a duty ratio range of 2.5% to 20%. Power delivery control includes power boosting in preparation for stimulation, and normal power regulation that adapts to both coupling and load variations. Only one pair of coils is used for both the power link and the bi-directional data link. Except for the secondary coil, the eye implant is fully integrated on chip and is fabricated using UMC (United Microelectronics Corporation, Hsinchu, Taiwan 0.13 μm complementary metal-oxide-semiconductor (CMOS process with a size of 1.5 mm × 1.5 mm. The secondary coil is fabricated on a printed circuit board (PCB with a diameter of only 4.4 mm. After coating with biocompatible silicone, the whole implant has dimensions of 6 mm in diameter with a thickness of less than 1 mm. The whole device can be put onto the sclera and beneath the eye’s conjunctiva. System functionality and electrical performance are demonstrated with measurement results.

Aids to Computer-Based Multimedia Learning.

Science.gov (United States)

Mayer, Richard E.; Moreno, Roxana

2002-01-01

Presents a cognitive theory of multimedia learning that draws on dual coding theory, cognitive load theory, and constructivist learning theory and derives some principles of instructional design for fostering multimedia learning. These include principles of multiple representation, contiguity, coherence, modality, and redundancy. (SLD)

Multimedia Instruction Initiative: Building Faculty Competence.

Science.gov (United States)

Haile, Penelope J.

Hofstra University began a university-wide initiative to enhance classroom instruction with multimedia technology and foster collaborative approaches to learning. The Multimedia Instruction Initiative emphasized teamwork among faculty, students, and computer center support staff to develop a technology-enriched learning environment supported by…

Insecurity of Wireless Networks

Energy Technology Data Exchange (ETDEWEB)

Sheldon, Frederick T [ORNL; Weber, John Mark [Dynetics, Inc.; Yoo, Seong-Moo [University of Alabama, Huntsville; Pan, W. David [University of Alabama, Huntsville

2012-01-01

Wireless is a powerful core technology enabling our global digital infrastructure. Wi-Fi networks are susceptible to attacks on Wired Equivalency Privacy, Wi-Fi Protected Access (WPA), and WPA2. These attack signatures can be profiled into a system that defends against such attacks on the basis of their inherent characteristics. Wi-Fi is the standard protocol for wireless networks used extensively in US critical infrastructures. Since the Wired Equivalency Privacy (WEP) security protocol was broken, the Wi-Fi Protected Access (WPA) protocol has been considered the secure alternative compatible with hardware developed for WEP. However, in November 2008, researchers developed an attack on WPA, allowing forgery of Address Resolution Protocol (ARP) packets. Subsequent enhancements have enabled ARP poisoning, cryptosystem denial of service, and man-in-the-middle attacks. Open source systems and methods (OSSM) have long been used to secure networks against such attacks. This article reviews OSSMs and the results of experimental attacks on WPA. These experiments re-created current attacks in a laboratory setting, recording both wired and wireless traffic. The article discusses methods of intrusion detection and prevention in the context of cyber physical protection of critical Internet infrastructure. The basis for this research is a specialized (and undoubtedly incomplete) taxonomy of Wi-Fi attacks and their adaptations to existing countermeasures and protocol revisions. Ultimately, this article aims to provide a clearer picture of how and why wireless protection protocols and encryption must achieve a more scientific basis for detecting and preventing such attacks.

A semantic medical multimedia retrieval approach using ontology information hiding.

Science.gov (United States)

Guo, Kehua; Zhang, Shigeng

2013-01-01

Searching useful information from unstructured medical multimedia data has been a difficult problem in information retrieval. This paper reports an effective semantic medical multimedia retrieval approach which can reflect the users' query intent. Firstly, semantic annotations will be given to the multimedia documents in the medical multimedia database. Secondly, the ontology that represented semantic information will be hidden in the head of the multimedia documents. The main innovations of this approach are cross-type retrieval support and semantic information preservation. Experimental results indicate a good precision and efficiency of our approach for medical multimedia retrieval in comparison with some traditional approaches.

Moodle 2.5 multimedia cookbook

CERN Document Server

Hilar, Silvina P

2013-01-01

With practical examples presented in the style of recipes, this book is designed for you to be able to dip in and out as you need, only using the multimedia options that you want at the time.This cookbook is designed specifically for teachers who want to begin creating interactive and engaging Moodle courses by utilizing the multimedia capabilities of Moodle.

Characterization of Industrial Coolant Fluids and Continuous Ageing Monitoring by Wireless Node-Enabled Fiber Optic Sensors

DEFF Research Database (Denmark)

Sachat, Alexandros El; Meristoudi, Anastasia; Markos, Christos

2017-01-01

Environmentally robust chemical sensors for monitoring industrial processes or infrastructures are lately becoming important devices in industry. Low complexity and wireless enabled characteristics can offer the required flexibility for sensor deployment in adaptable sensing networks for continuous...... of sensors allowed their integration in an autonomous wireless sensing node, thus enabling the future use of the demonstrated platform in wireless sensor networks for a variety of industrial and environmental monitoring applications....

Multimedia-Based Integration of Cross-Layer Techniques

Science.gov (United States)

2014-06-01

Wireless Commun. Mag., vol. 12, no. 4, pp. 50–58, August 2005. 11. E. Setton, T. Yoo, X. Zhu, A. Goldsmith , and B. Girod, “Cross-layer design of ad-hoc...Overview,” DARPA Presentation by Preston Marshall and Todd Martin, WAND Industry Day Workshop, Feb. 27, 2007. 17. S. Chan, “Shared spectrum access for DOD...Lavery, A. Goldsmith , and D. J. Goodman, “Throughput optimization using adaptive techniques,” IEEE Commun. Lett., pp. 1–7, 2006. 32. S. Choudhury and J

Light-weight internet protocol multimedia subsystem (IMS) client: development for smart mobile devices

CSIR Research Space (South Africa)

Masonta, M

2010-11-01

Full Text Available : IP multimedia Services Identity Module J2ME: Java 2 Micro-Edition JCP: Java Community Process JSR: Java Specification Request MAGNET: My personal Adaptive Global Network MGCF: Media Gateway Control Function MIDP: Mobile Information Device...) .................................................................. 30 Figure 2.15: IMS-Communicator Screenshot (PT Inova??o, 2007) .......................................... 31 Figure 2.16: UCT IMS Client Screenshot (Waiting & Good, 2007) ......................................... 32 Figure 3.1: Sun Java WTK 2...

Multimedia in forensics, security, and intelligence

NARCIS (Netherlands)

Battiato, S.; Emmanuel, S.; Ulges, A.; Worring, M.

2012-01-01

With the proliferation of multimedia data, it has become necessary to secure this content from illegal use, efficiently detect and reconstruct illegal activities from it, and use it as a source of intelligence. Serious challenges arise from the sheer data volume, however. The multimedia research

14 CFR 1213.108 - Multimedia materials.

Science.gov (United States)

2010-01-01

....108 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION RELEASE OF INFORMATION TO NEWS AND INFORMATION MEDIA § 1213.108 Multimedia materials. (a) NASA's multimedia material, from all... will provide the media, the public, and as necessary, NASA Headquarters with: (1) Selected prints and...

Application-oriented architecture for multimedia teleservices

Science.gov (United States)

Vanrijssen, Erwin; Widya, Ing; Michiels, Eddie

This paper looks into communications capabilities that are required by distributed multimedia applications to achieve relation preserving information exchange. These capabilities are derived by analyzing the notion of 'information exchange' and are embodied in communications functionalities. To emphasize the importance of the users' view, a top-down approach is applied. The revised Open Systems Interconnection (OSI) Application Layer Structure (OSI-ALS) is used to model the communications functionalities and to develop an architecture for composition of multimedia teleservices with these functionalities. This work may therefore be considered an exercise to evaluate the suitability of OSI-ALS for composition of multimedia teleservices.

Multimedia-assisted breathwalk-aware system.

Science.gov (United States)

Yu, Meng-Chieh; Wu, Huan; Lee, Ming-Sui; Hung, Yi-Ping

2012-12-01

Breathwalk is a science of combining specific patterns of footsteps synchronized with the breathing. In this study, we developed a multimedia-assisted Breathwalk-aware system which detects user's walking and breathing conditions and provides appropriate multimedia guidance on the smartphone. Through the mobile device, the system enhances user's awareness of walking and breathing behaviors. As an example application in slow technology, the system could help meditator beginners learn "walking meditation," a type of meditation which aims to be as slow as possible in taking pace, to synchronize footstep with breathing, and to land every footstep with toes first. In the pilot study, we developed a walking-aware system and evaluated whether multimedia-assisted mechanism is capable of enhancing beginner's walking awareness while walking meditation. Experimental results show that it could effectively assist beginners in slowing down the walking speed and decreasing incorrect footsteps. In the second experiment, we evaluated the Breathwalk-aware system to find a better feedback mechanism for learning the techniques of Breathwalk while walking meditation. The experimental results show that the visual-auditory mechanism is a better multimedia-assisted mechanism while walking meditation than visual mechanism and auditory mechanism.

Power control in wireless sensor networks with variable interference

NARCIS (Netherlands)

Chincoli, M.; Syed, A.A.; Exarchakos, G.; Liotta, A.

2016-01-01

Adaptive transmission power control schemes have been introduced in wireless sensor networks to adjust energy consumption under different network conditions. This is a crucial goal, given the constraints under which sensor communications operate. Power reduction may however have counterproductive

The development of multimedia communication system for electric power company

Energy Technology Data Exchange (ETDEWEB)

Woo, Hee Gon; Kim, Seong Bok [Korea Electric Power Corp. (KEPCO), Taejon (Korea, Republic of). Research Center

1995-12-31

It is a final report of the research project that is a development of PC-LAN based multimedia desktop conference system, which is research on the essential technologies and application and development of multimedia communication services for electric power company. This report is consisted of -Survey and study of the multimedia related technologies, -Multimedia communication protocols and network configurations, and -Design, developments of pilot model, evaluation, and applications of multimedia conference system. (author). 112 refs., 250 figs.

The development of multimedia communication system for electric power company

Energy Technology Data Exchange (ETDEWEB)

Woo, Hee Gon; Kim, Seong Bok [Korea Electric Power Corp. (KEPCO), Taejon (Korea, Republic of). Research Center

1996-12-31

It is a final report of the research project that is a development of PC-LAN based multimedia desktop conference system, which is research on the essential technologies and application and development of multimedia communication services for electric power company. This report is consisted of -Survey and study of the multimedia related technologies, -Multimedia communication protocols and network configurations, and -Design, developments of pilot model, evaluation, and applications of multimedia conference system. (author). 112 refs., 250 figs.

Effectiveness of multimedia-supported education in practical sports courses.

Science.gov (United States)

Leser, Roland; Baca, Arnold; Uhlig, Johannes

2011-01-01

Multimedia-assisted teaching and learning have become standard forms of education. In sports, multimedia material has been used to teach practical aspects of courses, such as motor skills. The main goal of this study is to examine if multimedia technology impacts learning in the field of sport motor skill acquisition. This question was investigated during a practical sports education course involving 35 students who participated in a university soccer class. The whole course was split into two groups: Group A was taught traditionally with no assistance of multimedia and Group B was prepared with multimedia-assisted instructional units. To quantify selected skills of soccer technique and tactic, the test subjects performed a specific passing test and a tactical assessment. Furthermore, a ques-tionnaire was used to assess the subjective impressions of the test subjects. All testing instruments were applied before and after a six-week-long teaching period. A comparison of the gathered data between the two groups resulted in no significant differences, neither concerning the results of the technique test nor concerning the tactic test. However, the results of the ques-tionnaire showed a positive agreement among the participants in the usability and assistance of multimedia for the sports practical course. Considering the reviewed conditions, it can be concluded that the use of multimedia content doesn't affect the learning effects. Key pointsMultimedia-assisted learning showed no positive learning effects on technical skills in soccer.Multimedia-assisted learning showed no positive learning effects on tactical skills in soccer.Students participating in practical sports courses have very good attitudes towards the use of multi-media learning material. This may be considered for motivational effects.

Effectiveness of Multimedia-Supported Education in Practical Sports Courses

Science.gov (United States)

Leser, Roland; Baca, Arnold; Uhlig, Johannes

2011-01-01

Multimedia-assisted teaching and learning have become standard forms of education. In sports, multimedia material has been used to teach practical aspects of courses, such as motor skills. The main goal of this study is to examine if multimedia technology impacts learning in the field of sport motor skill acquisition. This question was investigated during a practical sports education course involving 35 students who participated in a university soccer class. The whole course was split into two groups: Group A was taught traditionally with no assistance of multimedia and Group B was prepared with multimedia-assisted instructional units. To quantify selected skills of soccer technique and tactic, the test subjects performed a specific passing test and a tactical assessment. Furthermore, a ques-tionnaire was used to assess the subjective impressions of the test subjects. All testing instruments were applied before and after a six-week-long teaching period. A comparison of the gathered data between the two groups resulted in no significant differences, neither concerning the results of the technique test nor concerning the tactic test. However, the results of the ques-tionnaire showed a positive agreement among the participants in the usability and assistance of multimedia for the sports practical course. Considering the reviewed conditions, it can be concluded that the use of multimedia content doesn’t affect the learning effects. Key points Multimedia-assisted learning showed no positive learning effects on technical skills in soccer. Multimedia-assisted learning showed no positive learning effects on tactical skills in soccer. Students participating in practical sports courses have very good attitudes towards the use of multi-media learning material. This may be considered for motivational effects. PMID:24149313

Multimedia information retrieval theory and techniques

CERN Document Server

Raieli, Roberto

2013-01-01

Novel processing and searching tools for the management of new multimedia documents have developed. Multimedia Information Retrieval (MMIR) is an organic system made up of Text Retrieval (TR); Visual Retrieval (VR); Video Retrieval (VDR); and Audio Retrieval (AR) systems. So that each type of digital document may be analysed and searched by the elements of language appropriate to its nature, search criteria must be extended. Such an approach is known as the Content Based Information Retrieval (CBIR), and is the core of MMIR. This novel content-based concept of information handling needs to be integrated with more traditional semantics. Multimedia Information Retrieval focuses on the tools of processing and searching applicable to the content-based management of new multimedia documents. Translated from Italian by Giles Smith, the book is divided in to two parts. Part one discusses MMIR and related theories, and puts forward new methodologies; part two reviews various experimental and operating MMIR systems, a...

An Adaptive Allocation Algorithm Using Directional CSMA/CA over mmWave Wireless Personal Area Networks

Directory of Open Access Journals (Sweden)

Hyunhee Park

2012-04-01

Full Text Available Directional antennas have the considerable benefits of higher antenna gain, long transmission distance and spatial reuse compared to omni-antennas. To support a directional antenna, IEEE 802.15.3c specifies a high data transmission rate and short frequency range communication based on the characteristics of 60GHz band. However, the contention-based protocol of IEEE 802.15.3c may cause channel collisions and throughput degradation as the number of stations in the network increases. In order to resolve this problem and reduce channel access latency, we propose an adaptive allocation algorithm in which the contention window size for optimal transmission probability is derived after the directional information has been obtained by means of AP control procedures. Extensive simulations demonstrate that the proposed algorithm outperforms the existing channel access scheme in IEEE 802.15.3c wireless personal area networks under different situations, especially when the number of contending stations is large.

Multimedia chatting system on LAN

Science.gov (United States)

Lung, Chu-Sheng; Wang, Chun-Chao; Lee, Ching-Long; Huang, Huang-Chen

1994-04-01

An interactive system designed for talking via multimedia presentation with other parties on Ethernet- LAN is proposed. Our Multimedia Chatting System will take several media services into consideration, like still image, text, pen writing, voice, and slow-motion video, to integrate a practical chatting system. The prototyping subsystem to implement the above idea is currently under development using NETBIOS communication interface and Microsoft Windows environment.

Theoretical foundations: Formalized temporal models for hyperlinked multimedia documents

NARCIS (Netherlands)

B. Meixner (Britta)

2018-01-01

textabstractConsistent linking and accurate synchronization of multimedia elements in hypervideos or multimedia documents are essential to provide a good quality of experience to viewers. Temporal models are needed to define relationships and constraints between multimedia elements and create an

An authoring tool for building both mobile adaptable tests and web-based adaptive or classic tests

NARCIS (Netherlands)

Romero, C.; Ventura, S.; Hervás, C.; De Bra, P.M.E.; Wade, V.; Ashman, H.; Smyth, B.

2006-01-01

This paper describes Test Editor, an authoring tool for building both mobile adaptable tests and web-based adaptive or classic tests. This tool facilitates the development and maintenance of different types of XML-based multiple- choice tests for using in web-based education systems and wireless

Real-time-service-based Distributed Scheduling Scheme for IEEE 802.16j Networks

OpenAIRE

Kuo-Feng Huang; Shih-Jung Wu

2013-01-01

Supporting Quality of Service (QoS) guarantees for diverse multimedia services is the primary concern for IEEE802.16j networks. A scheduling scheme that satisfies the QoS requirements has become more important for wireless communications. We proposed an adaptive nontransparent-based distributed scheduling scheme (ANDS) for IEEE 802.16j networks. ANDS comprises three major components: Priority Assignment, Resource Allocation, Preserved Bandwidth Adjustment. Different service-type connections p...

Multimedia Category Preferences of Working Engineers

Science.gov (United States)

Baukal, Charles E., Jr.; Ausburn, Lynna J.

2016-01-01

Many have argued for the importance of continuing engineering education (CEE), but relatively few recommendations were found in the literature for how to use multimedia technologies to deliver it most effectively. The study reported here addressed this gap by investigating the multimedia category preferences of working engineers. Four categories…

Multimedia signal coding and transmission

CERN Document Server

Ohm, Jens-Rainer

2015-01-01

This textbook covers the theoretical background of one- and multidimensional signal processing, statistical analysis and modelling, coding and information theory with regard to the principles and design of image, video and audio compression systems. The theoretical concepts are augmented by practical examples of algorithms for multimedia signal coding technology, and related transmission aspects. On this basis, principles behind multimedia coding standards, including most recent developments like High Efficiency Video Coding, can be well understood. Furthermore, potential advances in future development are pointed out. Numerous figures and examples help to illustrate the concepts covered. The book was developed on the basis of a graduate-level university course, and most chapters are supplemented by exercises. The book is also a self-contained introduction both for researchers and developers of multimedia compression systems in industry.

Experimental Characterization of LTE Wireless Links in High-Speed Trains

Directory of Open Access Journals (Sweden)

Tomás Domínguez-Bolaño

2017-01-01

Full Text Available Multimedia and data-based services experienced a nonstopping growth over the last few years. People are continuously on the move using devices to access multimedia contents or other data-based services. Due to this, railway companies are showing a great interest in deploying broadband mobile wireless networks in high-speed-trains with the aim of supporting both passenger services provisioning as well as automatic train control and signaling. Nowadays, the most widely used technology for communications between trains and the railway infrastructure is GSM for Railways (GSM-R; however, it has limited capabilities to support such advanced services. Due to its success in the mass market, Long Term Evolution (LTE seems to be the best candidate to substitute GSM-R. In this paper, we experimentally characterize the downlink between an LTE Evolved NodeB (eNodeB and a high-speed train in a commercial high-speed line. We consider two links: the one between the eNodeB and the antennas placed outdoors on the train roof, and the direct link between the eNodeB and a receiver inside the train. Such a characterization consists in assessing the path loss, the Signal to Noise Ratio, the K-Factor, the Power Delay Profile, the delay spread, and the Doppler Power Spectral Density.

Wireless network interface energy consumption implications of popular streaming formats

Science.gov (United States)

Chandra, Surendar

2001-12-01

With the proliferation of mobile streaming multimedia, available battery capacity constrains the end-user experience. Since streaming applications tend to be long running, wireless network interface card's (WNIC) energy consumption is particularly an acute problem. In this work, we explore the WNIC energy consumption implications of popular multimedia streaming formats from Microsoft (Windows media), Real (Real media) and Apple (Quick Time). We investigate the energy consumption under varying stream bandwidth and network loss rates. We also explore history-based client-side strategies to reduce the energy consumed by transitioning the WNICs to a lower power consuming sleep state. We show that Microsoft media tends to transmit packets at regular intervals; streams optimized for 28.8 Kbps can save over 80% in energy consumption with 2% data loss. A high bandwidth stream (768 Kbps) can still save 57% in energy consumption with less than 0.3% data loss. For high bandwidth streams, Microsoft media exploits network-level packet fragmentation, which can lead to excessive packet loss (and wasted energy) in a lossy network. Real stream packets tend to be sent closer to each other, especially at higher bandwidths. Quicktime packets sometimes arrive in quick succession; most likely an application level fragmentation mechanism. Such packets are harder to predict at the network level without understanding the packet semantics.

Reactive and adaptive monitoring to secure aggregation in wireless sensor networks

NARCIS (Netherlands)

Labraoui, Nabila; Gueroui, Mourad; Aliouat, Makhlouf; Petit, Jonathan

Data aggregation is considered as one of the fundamental distributed data processing procedures for saving the energy and minimizing the medium access layer contention in wireless sensor networks. However, sensor networks are likely to be deployed in an untrusted environment, which make them

Intelligent Interactive Multimedia

CERN Document Server

Watanabe, Toyohide; Takahashi, Naohisa; 5th International Conference on Intelligent Interactive Multimedia Systems and Services

2012-01-01

This volume contains the Proceedings of the 5th International Conference on Intelligent Interactive Multimedia Systems and Services (KES-IIMSS-12).  The Conference was jointly organised by Nagoya University in Japan and the KES International organisation, and held in the attractive city of Gifu.   The KES-IIMSS conference series, (series chairs Prof. Maria Virvou and Prof. George Tsihrintzis), presents novel research in various areas of intelligent multimedia system relevant to the development of a new generation of interactive, user-centric devices and systems.  The aim of the conference is to provide an internationally respected forum for scientific research in the technologies and applications of this new and dynamic research area.

Multimedia content management in MPEG-21 framework

Science.gov (United States)

Smith, John R.

2002-07-01

MPEG-21 is an emerging standard from MPEG that specifies a framework for transactions of multimedia content. MPEG-21 defines the fundamental concept known as a digital item, which is the unit of transaction in the multimedia framework. A digital item can be used to package content for such as a digital photograph, a video clip or movie, a musical recording with graphics and liner notes, a photo album, and so on. The packaging of the media resources, corresponding identifiers, and associated metadata is provided in the declaration of the digital item. The digital item declaration allows for more effective transaction, distribution, and management of multimedia content and corresponding metadata, rights expressions, variations of media resources. In this paper, we describe various challenges for multimedia content management in the MPEG-21 framework.

Freie Mitarbeit im Multimedia-Markt

OpenAIRE

Böhm, Dietmar; Volkert, Bernd

1998-01-01

Der Arbeitsbericht konzentriert die Betrachtung auf die Angebotsseite des Multimedia-Arbeitsmarktes. Gleichwohl wird in einigen Punkten auch die Sicht der Nachfrager, also der Multimedia-Unternehmen, einbezogen. Die Überlegungen zur Abgrenzung der freien Mitarbeit von anderen Formen der Erwerbstätigkeit zeigen, dass die freie Mitarbeit in einem Zwischenbereich anzusiedeln ist, der durch mehrfache fließende Übergänge bzw. Überschneidungen charakterisiert ist. Aus der Analyse von Stellengesuche...

Distributed multimedia database technologies supported by MPEG-7 and MPEG-21

CERN Document Server

Kosch, Harald

2003-01-01

15 Introduction Multimedia Content: Context Multimedia Systems and Databases (Multi)Media Data and Multimedia Metadata Purpose and Organization of the Book MPEG-7: The Multimedia Content Description Standard Introduction MPEG-7 and Multimedia Database Systems Principles for Creating MPEG-7 Documents MPEG-7 Description Definition Language Step-by-Step Approach for Creating an MPEG-7 Document Extending the Description Schema of MPEG-7 Encoding and Decoding of MPEG-7 Documents for Delivery-Binary Format for MPEG-7 Audio Part of MPEG-7 MPEG-7 Supporting Tools and Referen

Service Class Resource Management For Green Wireless-Optical Broadband Access NetworksWOBAN

Directory of Open Access Journals (Sweden)

SRUTHY.S

2015-08-01

Full Text Available Abstract-Broadband access networks have become an essential part of worldwide communication systems because of the exponential growth of broadband services such as video on demand high definition TV internet protocol TV and video conferencing. Exponential growth in the volume of wireless data boosted by the growing popularity of mobile devices such as smartphone and tablets has forced the telecommunication industries to rethink the way networks are currently designed and to focus on the development of high-capacity mobile broadband networks. In response to this challenge researchers have been working toward the development of an integrated wireless optical broadband access network. Two major candidate technologies which are currently known for their high capacity as well as quality of service QoS for multimedia traffic are passive optical networks PON and fourth generation 4G wireless networks. PON is a wired access technology well known for its cost efficiency and high capacity whereas 4G is a wireless broadband access technology which has achieved broad market acceptance because of its ease of deployment ability to offer mobility and its cost efficiency. Integration of PON and 4G technologies in the form of wireless-optical broadband access networks offers advantages such as extension of networks in rural areas support for mobile broadband services and quick deployment of broadband networks. These two technologies however have different design architectures for handling broadband services that require quality of service. For example 4G networks use traffic classification for supporting different QoS demands whereas the PON architecture has no such mechanism to differentiate between types of traffic. These two technologies also differ in their power saving mechanisms. Propose a service class mapping for the integrated PON-4G network which is based on the MG1 queuing model and class-based power saving mechanism which significantly improves the

A Multitude of Risks in Multimedia.

Science.gov (United States)

Loving, Bill

Multimedia presentations offer educators and other communicators new avenues to reach audiences, but they combine a variety of legal hazards. Producers of multimedia can end up on the receiving end of lawsuits based on the many facets of copyright, privacy, and defamation law, as this guide illustrates. Copyright gives authors, composers,…

New generation of the multimedia search engines

Science.gov (United States)

Mijes Cruz, Mario Humberto; Soto Aldaco, Andrea; Maldonado Cano, Luis Alejandro; López Rodríguez, Mario; Rodríguez Vázqueza, Manuel Antonio; Amaya Reyes, Laura Mariel; Cano Martínez, Elizabeth; Pérez Rosas, Osvaldo Gerardo; Rodríguez Espejo, Luis; Flores Secundino, Jesús Abimelek; Rivera Martínez, José Luis; García Vázquez, Mireya Saraí; Zamudio Fuentes, Luis Miguel; Sánchez Valenzuela, Juan Carlos; Montoya Obeso, Abraham; Ramírez Acosta, Alejandro Álvaro

2016-09-01

Current search engines are based upon search methods that involve the combination of words (text-based search); which has been efficient until now. However, the Internet's growing demand indicates that there's more diversity on it with each passing day. Text-based searches are becoming limited, as most of the information on the Internet can be found in different types of content denominated multimedia content (images, audio files, video files). Indeed, what needs to be improved in current search engines is: search content, and precision; as well as an accurate display of expected search results by the user. Any search can be more precise if it uses more text parameters, but it doesn't help improve the content or speed of the search itself. One solution is to improve them through the characterization of the content for the search in multimedia files. In this article, an analysis of the new generation multimedia search engines is presented, focusing the needs according to new technologies. Multimedia content has become a central part of the flow of information in our daily life. This reflects the necessity of having multimedia search engines, as well as knowing the real tasks that it must comply. Through this analysis, it is shown that there are not many search engines that can perform content searches. The area of research of multimedia search engines of new generation is a multidisciplinary area that's in constant growth, generating tools that satisfy the different needs of new generation systems.

Atmospheric turbulence effects on the performance of the laser wireless power transfer system

Science.gov (United States)

Kapranov, V. V.; Matsak, I. S.; Tugaenko, V. Yu.; Blank, A. V.; Suhareva, N. A.

2017-02-01

Application of adaptive correction is necessary to control wandering of the laser beam in wireless power transfer (WPT) system. In this paper we describe experimental results of using different adaptive correction techniques for both weak and strong turbulence conditions. All experiments were performed over a 1.5 km near-horizontal atmospheric path. Some criteria for choosing parameters of adaptive correction are given.

Multimedia in German Libraries--Aspects of Cooperation and Integration.

Science.gov (United States)

Cremer, Monika

This paper on multimedia in German libraries begins with an introduction to multimedia. Initiatives of the federal government and in the Laender (federal states) are then described, including: a 1997 symposium organized by the university library of Goettingen that presented several multimedia models developed in universities; the multimedia…

Multimedia over cognitive radio networks algorithms, protocols, and experiments

CERN Document Server

Hu, Fei

2014-01-01

PrefaceAbout the EditorsContributorsNetwork Architecture to Support Multimedia over CRNA Management Architecture for Multimedia Communication in Cognitive Radio NetworksAlexandru O. Popescu, Yong Yao, Markus Fiedler , and Adrian P. PopescuPaving a Wider Way for Multimedia over Cognitive Radios: An Overview of Wideband Spectrum Sensing AlgorithmsBashar I. Ahmad, Hongjian Sun, Cong Ling, and Arumugam NallanathanBargaining-Based Spectrum Sharing for Broadband Multimedia Services in Cognitive Radio NetworkYang Yan, Xiang Chen, Xiaofeng Zhong, Ming Zhao, and Jing WangPhysical Layer Mobility Challen

Advanced Technologies, Embedded and Multimedia for Human-Centric Computing

CERN Document Server

Chao, Han-Chieh; Deng, Der-Jiunn; Park, James; HumanCom and EMC 2013

2014-01-01

The theme of HumanCom and EMC are focused on the various aspects of human-centric computing for advances in computer science and its applications, embedded and multimedia computing and provides an opportunity for academic and industry professionals to discuss the latest issues and progress in the area of human-centric computing. And the theme of EMC (Advanced in Embedded and Multimedia Computing) is focused on the various aspects of embedded system, smart grid, cloud and multimedia computing, and it provides an opportunity for academic, industry professionals to discuss the latest issues and progress in the area of embedded and multimedia computing. Therefore this book will be include the various theories and practical applications in human-centric computing and embedded and multimedia computing.

Multimedia and Communication Curricula: The Medium vs. the Message

Directory of Open Access Journals (Sweden)

Abderrahmane Azzi

1998-12-01

Full Text Available Multimedia technology is restructuring the field of communication in various ways. The prevalent nature of this new media invites flexibility which can make communication curricula accommodate a wide range of competencies including technical competency. I have argued in this paper that multimedia, much like printing, radio, television and film, is mainly the means whereby content is delivered. Central to multimedia are content and effects. Content requires perspective which can then be reproduced in texts and images, while effects involves assessment of the influence of multimedia on society and culture. As such, multimedia needs to be approached from a mass communication perspective which preserves the identity of the field and provides a vital link between theory and practical application.

Multi-Channel Multi-Radio Using 802.11 Based Media Access for Sink Nodes in Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Kok-Keong Loo

2011-05-01

Full Text Available The next generation surveillance and multimedia systems will become increasingly deployed as wireless sensor networks in order to monitor parks, public places and for business usage. The convergence of data and telecommunication over IP-based networks has paved the way for wireless networks. Functions are becoming more intertwined by the compelling force of innovation and technology. For example, many closed-circuit TV premises surveillance systems now rely on transmitting their images and data over IP networks instead of standalone video circuits. These systems will increase their reliability in the future on wireless networks and on IEEE 802.11 networks. However, due to limited non-overlapping channels, delay, and congestion there will be problems at sink nodes. In this paper we provide necessary conditions to verify the feasibility of round robin technique in these networks at the sink nodes by using a technique to regulate multi-radio multichannel assignment. We demonstrate through simulations that dynamic channel assignment scheme using multi-radio, and multichannel configuration at a single sink node can perform close to optimal on the average while multiple sink node assignment also performs well. The methods proposed in this paper can be a valuable tool for network designers in planning network deployment and for optimizing different performance objectives.

Multi-channel multi-radio using 802.11 based media access for sink nodes in wireless sensor networks.

Science.gov (United States)

Campbell, Carlene E-A; Khan, Shafiullah; Singh, Dhananjay; Loo, Kok-Keong

2011-01-01

The next generation surveillance and multimedia systems will become increasingly deployed as wireless sensor networks in order to monitor parks, public places and for business usage. The convergence of data and telecommunication over IP-based networks has paved the way for wireless networks. Functions are becoming more intertwined by the compelling force of innovation and technology. For example, many closed-circuit TV premises surveillance systems now rely on transmitting their images and data over IP networks instead of standalone video circuits. These systems will increase their reliability in the future on wireless networks and on IEEE 802.11 networks. However, due to limited non-overlapping channels, delay, and congestion there will be problems at sink nodes. In this paper we provide necessary conditions to verify the feasibility of round robin technique in these networks at the sink nodes by using a technique to regulate multi-radio multichannel assignment. We demonstrate through simulations that dynamic channel assignment scheme using multi-radio, and multichannel configuration at a single sink node can perform close to optimal on the average while multiple sink node assignment also performs well. The methods proposed in this paper can be a valuable tool for network designers in planning network deployment and for optimizing different performance objectives.

A Survey on Simultaneous Wireless Information and Power Transfer

Science.gov (United States)

Perera, T. D. P.; Jayakody, D. N. K.; De, S.; Ivanov, M. A.

2017-01-01

This paper presents a comprehensive study related to simultaneous wireless information and power transfer (SWIPT) in different types of wireless communication setups. Harvesting energy using SWIPT is an appealing solution in the context of extending battery life of wireless devices for a fully sustainable communication system. Strong signal power increases power transfer, but also causes more interference in information transfer, causing realization of the SWIPT challenging problem. This article provides an overview of technical evolution of SWIPT. A survey and qualitative comparison of the existing SWIPT schemes is provided to demonstrate their limitations in the current and 5G networks. Open challenges are emphasized and guidelines are provided to adapt the existing schemes in order to overcome these limitations and make them fit for integrating with the modern and emerging next generation communication networks, such as 5G systems.

Fiber-wireless integrated mobile backhaul network based on a hybrid millimeter-wave and free-space-optics architecture with an adaptive diversity combining technique.

Science.gov (United States)

Zhang, Junwen; Wang, Jing; Xu, Yuming; Xu, Mu; Lu, Feng; Cheng, Lin; Yu, Jianjun; Chang, Gee-Kung

2016-05-01

We propose and experimentally demonstrate a novel fiber-wireless integrated mobile backhaul network based on a hybrid millimeter-wave (MMW) and free-space-optics (FSO) architecture using an adaptive combining technique. Both 60 GHz MMW and FSO links are demonstrated and fully integrated with optical fibers in a scalable and cost-effective backhaul system setup. Joint signal processing with an adaptive diversity combining technique (ADCT) is utilized at the receiver side based on a maximum ratio combining algorithm. Mobile backhaul transportation of 4-Gb/s 16 quadrature amplitude modulation frequency-division multiplexing (QAM-OFDM) data is experimentally demonstrated and tested under various weather conditions synthesized in the lab. Performance improvement in terms of reduced error vector magnitude (EVM) and enhanced link reliability are validated under fog, rain, and turbulence conditions.

Efficacy of Multimedia Package in Communicative Skill in English

Science.gov (United States)

Singaravelu, G.

2014-01-01

The study enlightens the effectiveness of Multimedia Package in learning communicative skill in English. Objectives of the study: To prepare a Multimedia Package for developing communicative skill in English. To find out the impact of Multimedia Package in improving communicative skill in English. Quasi Experimental method was adopted in the…

Edification of Multimedia Resources: Aligning Technology for Student Empowerment

Science.gov (United States)

Thamarasseri, Ismail

2014-01-01

Multimedia offers exciting possibilities for meeting the needs of 21st century learners. Multimedia learning can be defined in a number of ways. Multimedia learning is the delivery of instructional content using multiple modes that include visual and auditory information and students' use of this information to construct knowledge. Today's…

An Overview of Multimedia and the Law.

Science.gov (United States)

Boelzner, David E.

2000-01-01

Reviews the areas of intellectual property law, including patent, copyright, and trademark, and discusses how multimedia raises legal issues in each area. Discusses trade secrets, issues raised by online technology, and issues for licensing and developing multimedia works. (Author/LRW)

Graceful degradation of CACC performance subject to unreliable wireless communication

NARCIS (Netherlands)

Ploeg, J.; Semsar-Kazerooni, E.; Lijster, G.; Wouw, N. van de; Nijmeijer, H.

2013-01-01

Cooperative Adaptive Cruise Control (CACC) employs wireless intervehicle communication, in addition to onboard sensors, to obtain string-stable vehicle-following behavior at small intervehicle distances. As a consequence, however, CACC is vulnerable to communication impairments such as packet loss,

On the power and offset allocation for rate adaptation of spatial multiplexing in optical wireless MIMO channels

KAUST Repository

Park, Kihong; Ko, Youngchai; Alouini, Mohamed-Slim

2011-01-01

Visible light communication (VLC) using optical sources which can be simultaneously utilized for illumination and communication is currently an attractive option for wireless personal area network. Improving the data rate in optical wireless

IPTV technology for the wireless Internet service provider (WISP

Directory of Open Access Journals (Sweden)

Mitchell Vásquez Bermúdez

2018-02-01

Full Text Available This article describes the implementation of the IPTV technology through an open source system for the wireless Internet service provider (WISP in the Cerecita site, located in the province of Guayas, Ecuador. The feasibility of implementing the IPTV technology is given through the use of the Emby Server application, in addition to the use of an operating system such as CentOS 7, which are open source and have the necessary requirements for the creation of this service. The analysis of data tra c generated on the WISP network, which will establish the advantages and disadvantages generated by the transmission of this technology, created to VOD multimedia content server that allows the video signal to be sent to users Finally, a feasibility study was carried out to analyze the advantages and disadvantages that exist in the implementation of this IPTV technology.

Service Characteristics Based High Speed Multimedia Transport Protocol

National Research Council Canada - National Science Library

Chen, C

1997-01-01

.... This multimedia protocol will automatically extract service requirements from multimedia applications by selecting certain sets of parameters from user applications to optimally drive the lower level physical network...

Energy-Aware Routing Protocol for Ad Hoc Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Mann Raminder P

2005-01-01

Full Text Available Wireless ad hoc sensor networks differ from wireless ad hoc networks from the following perspectives: low energy, lightweight routing protocols, and adaptive communication patterns. This paper proposes an energy-aware routing protocol (EARP suitable for ad hoc wireless sensor networks and presents an analysis for its energy consumption in various phases of route discovery and maintenance. Based on the energy consumption associated with route request processing, EARP advocates the minimization of route requests by allocating dynamic route expiry times. This paper introduces a unique mechanism for estimation of route expiry time based on the probability of route validity, which is a function of time, number of hops, and mobility parameters. In contrast to AODV, EARP reduces the repeated flooding of route requests by maintaining valid routes for longer durations.

Principles of Multimedia News Systems for Business Applications

OpenAIRE

Ioan I. ANDONE

2009-01-01

In the past few years considerable demand for business oriented multimedia information systems has developed. A multimedia information system is one that can create, import, integrate, store, retrieve, edit, and delete two or more types of media materials in digital form, such as audio, image, full-motion video, and text information. Multimedia information systems play a central role in many business activities. They represent a very special class complex computing systems. This paper surveys...

The efficiency of multimedia learning into old age.

Science.gov (United States)

Van Gerven, Pascal W M; Paas, Fred; Van Merriënboer, Jeroen J G; Hendriks, Maaike; Schmidt, Henk G

2003-12-01

On the basis of a multimodal model of working memory, cognitive load theory predicts that a multimedia-based instructional format leads to a better acquisition of complex subject matter than a purely visual instructional format. This study investigated the extent to which age and instructional format had an impact on training efficiency among both young and old adults. It was hypothesised that studying worked examples that are presented as a narrated animation (multimedia condition) is a more efficient means of complex skill training than studying visually presented worked examples (unimodal condition) and solving conventional problems. Furthermore, it was hypothesised that multimedia-based worked examples are especially helpful for elderly learners, who have to deal with a general decline of working-memory resources, because they address both mode-specific working-memory stores. The sample consisted of 60 young (mean age = 15.98 years) and 60 old adults (mean age = 64.48 years). Participants of both age groups were trained in either a conventional, a unimodal, or a multimedia condition. Subsequently, they had to solve a series of test problems. Dependent variables were perceived cognitive load during the training, performance on the test, and efficiency in terms of the ratio between these two variables. Results showed that for both age groups multimedia-based worked examples were more efficient than the other training formats in that less cognitive load led to at least an equal performance level. Although no difference in the beneficial effect of multimedia learning was found between the age groups, multimedia-based instructions seem promising for the elderly.

Contemporary, emerging, and ratified wireless security standards: an update for the networked dental office.

Science.gov (United States)

Mupparapu, Muralidhar

2006-02-15

Wireless networking is not new to contemporary dental offices around the country. Wireless routers and network cards have made access to patient records within the office handy and, thereby, saving valuable chair side time and increasing productivity. As is the case with any rapidly developing technology, wireless technology also changes with the same rate. Unless, the users of the wireless networking understand the implications of these changes and keep themselves updated periodically, the office network will become obsolete very quickly. This update of the emerging security protocols and pertaining to ratified wireless 802.11 standards will be timely for the contemporary dentist whose office is wirelessly networked. This article brings the practicing dentist up-to-date on the newer versions and standards in wireless networking that are changing at a fast pace. The introduction of newer 802.11 standards like super G, Super AG, Multiple Input Multiple Output (MIMO), and pre-n are changing the pace of adaptation of this technology. Like any other rapidly transforming technology, information pertaining to wireless networking should be a priority for the contemporary dentist, an eventual end-user in order to be a well-informed and techno-savvy consumer.

Multimedia pembelajaran digital untuk meningkatkan antusiasme siswa dalam belajar

Directory of Open Access Journals (Sweden)

Neni Kusuma Nugraheni

2017-01-01

Full Text Available Penelitian ini bertujuan untuk mengembangkan media pembelajaran yang dapat meningkatan antusiasme siswa dalam belajar menggunakan multimedia digital storytelling. Untuk mewujudkan adanya multimedia digital storytelling tersebut, peneliti menggunakan metode pengembangan model ADDIE (analysis-design-develop-implement-evaluate. Hasil penelitian menunjukkan bahwa, multimedia digital storytelling memenuhi standar kelayakan bila digunakan untuk menunjang proses pembelajaran. Terbukti dengan hasil penilaian yang diberikan oleh  ahli media sebesar 79,2%, ahli materi sebesar 85,3% dan siswa sebesar 87%. Berdasarkan analisis hasil Uji t Berpasangan, peneliti menemukan adanya perbedaan antara sebelum dan sesudah menggunakan multimedia digital storytelling dalam pembelajaran yang mendapat skor rata-rata sebesar -6.75 dan dengan standart deviasi sebesar 3.808. Sedangkan hasil yang didapat untuk sig sebesar 0.002 = 0.2 % < 5 %; maka hal itu berarti bahwa, rata-rata antusiasme siswa dalam mengikuti pembelajaran antara yang sebelum dan sesudah menggunakan multimedia digital storytelling terdapat perbedaan dan mengalami perubahan. Dengan demikian peneliti menyimpulkan bahwa, penggunaan multimedia digital storytelling untuk menunjang proses pembelajaran dapat meningkatkan antusiasme siswa dalam belajar.

An ultra low-power and traffic-adaptive medium access control protocol for wireless body area network.

Science.gov (United States)

Ullah, Sana; Kwak, Kyung Sup

2012-06-01

Wireless Body Area Network (WBAN) consists of low-power, miniaturized, and autonomous wireless sensor nodes that enable physicians to remotely monitor vital signs of patients and provide real-time feedback with medical diagnosis and consultations. It is the most reliable and cheaper way to take care of patients suffering from chronic diseases such as asthma, diabetes and cardiovascular diseases. Some of the most important attributes of WBAN is low-power consumption and delay. This can be achieved by introducing flexible duty cycling techniques on the energy constraint sensor nodes. Stated otherwise, low duty cycle nodes should not receive frequent synchronization and control packets if they have no data to send/receive. In this paper, we introduce a Traffic-adaptive MAC protocol (TaMAC) by taking into account the traffic information of the sensor nodes. The protocol dynamically adjusts the duty cycle of the sensor nodes according to their traffic-patterns, thus solving the idle listening and overhearing problems. The traffic-patterns of all sensor nodes are organized and maintained by the coordinator. The TaMAC protocol is supported by a wakeup radio that is used to accommodate emergency and on-demand events in a reliable manner. The wakeup radio uses a separate control channel along with the data channel and therefore it has considerably low power consumption requirements. Analytical expressions are derived to analyze and compare the performance of the TaMAC protocol with the well-known beacon-enabled IEEE 802.15.4 MAC, WiseMAC, and SMAC protocols. The analytical derivations are further validated by simulation results. It is shown that the TaMAC protocol outperforms all other protocols in terms of power consumption and delay.

Energy-efficient digital and wireless IC design for wireless smart sensing

Science.gov (United States)

Zhou, Jun; Huang, Xiongchuan; Wang, Chao; Tae-Hyoung Kim, Tony; Lian, Yong

2017-10-01

Wireless smart sensing is now widely used in various applications such as health monitoring and structural monitoring. In conventional wireless sensor nodes, significant power is consumed in wirelessly transmitting the raw data. Smart sensing adds local intelligence to the sensor node and reduces the amount of wireless data transmission via on-node digital signal processing. While the total power consumption is reduced compared to conventional wireless sensing, the power consumption of the digital processing becomes as dominant as wireless data transmission. This paper reviews the state-of-the-art energy-efficient digital and wireless IC design techniques for reducing the power consumption of the wireless smart sensor node to prolong battery life and enable self-powered applications.

Transmission techniques for emergent multicast and broadcast systems

CERN Document Server

da Silva, Mario Marques; Dinis, Rui; Souto, Nuno; Silva, Joao Carlos

2010-01-01

Describing efficient transmission schemes for broadband wireless systems, Transmission Techniques for Emergent Multicast and Broadcast Systems examines advances in transmission techniques and receiver designs capable of supporting the emergent wireless needs for multimedia broadcast and multicast service (MBMS) requirements. It summarizes the research and development taking place in wireless communications for multimedia MBMS and addresses the means to improved spectral efficiency to allow for increased user bit rate, as well as increased capacity of the digital cellular radio network.The text

Optical frequency upconversion technique for transmission of wireless MIMO-type signals over optical fiber.

Science.gov (United States)

Shaddad, R Q; Mohammad, A B; Al-Gailani, S A; Al-Hetar, A M

2014-01-01

The optical fiber is well adapted to pass multiple wireless signals having different carrier frequencies by using radio-over-fiber (ROF) technique. However, multiple wireless signals which have the same carrier frequency cannot propagate over a single optical fiber, such as wireless multi-input multi-output (MIMO) signals feeding multiple antennas in the fiber wireless (FiWi) system. A novel optical frequency upconversion (OFU) technique is proposed to solve this problem. In this paper, the novel OFU approach is used to transmit three wireless MIMO signals over a 20 km standard single mode fiber (SMF). The OFU technique exploits one optical source to produce multiple wavelengths by delivering it to a LiNbO3 external optical modulator. The wireless MIMO signals are then modulated by LiNbO3 optical intensity modulators separately using the generated optical carriers from the OFU process. These modulators use the optical single-sideband with carrier (OSSB+C) modulation scheme to optimize the system performance against the fiber dispersion effect. Each wireless MIMO signal is with a 2.4 GHz or 5 GHz carrier frequency, 1 Gb/s data rate, and 16-quadrature amplitude modulation (QAM). The crosstalk between the wireless MIMO signals is highly suppressed, since each wireless MIMO signal is carried on a specific optical wavelength.

Multimedia on nuclear reactors physics

International Nuclear Information System (INIS)

Dies, Javier; Puig, Francesc

2010-01-01

The paper present an example of measures that have been found to be effective in the development of innovative educational and training technology. A multimedia course on nuclear reactor physics is presented. This material has been used for courses at master level at the universities; training for engineers at nuclear power plant as modular 2 weeks course; and training operators of nuclear power plant. The multimedia has about 785 slides and the text is in English, Spanish and French. (authors)

Design and Analysis of QoS Routing Framework integrated with OLSR protocol for Multimedia Traffic in Mobile Adhoc Networks

Directory of Open Access Journals (Sweden)

S. Soni

2017-06-01

Full Text Available MANETs (Mobile Ad-hoc Networks is the self organizing wireless structure of mobile hosts. Wireless media is used for communication in MANETs. Considering the developing requirements for multimedia and real-time traffic applications in real world, QoS (Quality-of-Service support is essential in MANETs. But most of the characteristics of MANETs make QoS support a difficult problem. It is challenging to support QoS routing in MANET due to dynamic behavior and mobility of the hosts. The OLSR (Optimized Link State Routing protocol can be efficiently used in MANETs to provide QoS routing because of its dynamic MPR (Multi Point Relay selection criteria and proactive nature. In this paper, a design of QoS routing framework integrated with OLSR protocol is proposed and also analyzed using network simulator. Proposed QoS framework combines a bandwidth estimation algorithm with explicit resource reservation, QoS routing and connection admission control (CAC. OLSR protocol is extended for QoS framework to solve performance issues related to node mobility using cross layer approach. Results after simulation conclude about efficiency of the proposed QoS routing framework.

EFFECTIVENESS OF MULTIMEDIA-SUPPORTED EDUCATION IN PRACTICAL SPORTS COURSES

Directory of Open Access Journals (Sweden)

Roland Leser

2011-03-01

Full Text Available Multimedia-assisted teaching and learning have become standard forms of education. In sports, multimedia material has been used to teach practical aspects of courses, such as motor skills. The main goal of this study is to examine if multimedia technology impacts learning in the field of sport motor skill acquisition. This question was investigated during a practical sports education course involving 35 students who participated in a university soccer class. The whole course was split into two groups: Group A was taught traditionally with no assistance of multimedia and Group B was prepared with multimedia-assisted instructional units. To quantify selected skills of soccer technique and tactic, the test subjects performed a specific passing test and a tactical assessment. Furthermore, a ques-tionnaire was used to assess the subjective impressions of the test subjects. All testing instruments were applied before and after a six-week-long teaching period. A comparison of the gathered data between the two groups resulted in no significant differences, neither concerning the results of the technique test nor concerning the tactic test. However, the results of the ques-tionnaire showed a positive agreement among the participants in the usability and assistance of multimedia for the sports practical course. Considering the reviewed conditions, it can be concluded that the use of multimedia content doesn't affect the learning effects.

New Review of Hypermedia and Multimedia (NRHM)

DEFF Research Database (Denmark)

developments also take place in related fields like augmented reality, pervasive computing, mobile computing, CSCW, and HCI. With this special issue, we document the cross-fertilization between hypermedia and relevant ubiquitous and pervasive computing research fields to explore new forms of hypermedia. We...... have an excellent collection of six papers discussing mobile hypermedia, context-aware hypermedia, physical hypermedia, augmented reality-based hypermedia, and hypermedia on digital paper. The first two papers, Hypermedia in the Ambient Wood by Mark J. Weal, Danius T. Michaelides, Mark K. Thompson...... to the area of mobile hypermedia. Here, though, the focus is primarily on multimedia and 3D graphics-based augmented reality for wearable computers. The paper presents an advanced authoring tool for augmented reality-based mobile hypermedia. The fouth paper, Augmented Reality as an Interface to Adaptive...

Indoor Wireless RF Energy Transfer for Powering Wireless Sensors

Directory of Open Access Journals (Sweden)

H. Visser

2012-12-01

Full Text Available For powering wireless sensors in buildings, rechargeable batteries may be used. These batteries will be recharged remotely by dedicated RF sources. Far-field RF energy transport is known to suffer from path loss and therefore the RF power available on the rectifying antenna or rectenna will be very low. As a consequence, the RF-to-DC conversion efficiency of the rectenna will also be very low. By optimizing not only the subsystems of a rectenna but also taking the propagation channel into account and using the channel information for adapting the transmit antenna radiation pattern, the RF energy transport efficiency will be improved. The rectenna optimization, channel modeling and design of a transmit antenna are discussed.

An Evaluation of Media-Oriented Rate Selection Algorithm for Multimedia Transmission in MANETs

Directory of Open Access Journals (Sweden)

Guionnet Thomas

2005-01-01

Full Text Available We focus on the optimization of real-time multimedia transmission over 802.11-based ad hoc networks. In particular, we propose a simple and efficient cross-layer mechanism that considers both the channel conditions and characteristics of the media for dynamically selecting the transmission mode. This mechanism called media-oriented rate selection algorithm (MORSA targets loss-tolerant applications such as VoD that do not require full reliable transmission. We provide an evaluation of this mechanism for MANETs using simulations with NS and analyze the video quality obtained with a fine-grain scalable video encoder based on a motion-compensated spatiotemporal wavelet transform. Our results show that MORSA achieves up to 4 Mbps increase in throughput and that the routing overhead decreases significantly. Transmission of a sample video flow over an 802.11a wireless channel has been evaluated with MORSA. Important improvement is observed in throughput, latency, and jitter while keeping a good level of video quality.

Survey on Multimedia Technologies for Mobile Learning Applications

Directory of Open Access Journals (Sweden)

Paul POCATILU

2009-01-01

Full Text Available Mobile technologies are developing very fast. This paper presents a survey on multimedia technologies for mobile learning applications, focusing on multimedia programming techniques for Windows Mobile, Symbian, and Java ME.

Real-time resource availability signaling in IP multimedia subsystem networks

NARCIS (Netherlands)

Ozcelebi, T.; Radovanovic, I.; Sengupta, D.

2008-01-01

IP Multimedia Subsystem (IMS) allows the use of unlicensed, non-dedicated and nondeterministic access networks for delivering IP multimedia services. Providing end-to-end Quality-of-Service (QoS) for resource demanding real-time services (e.g. real-time multimedia) over such networks is a

Design of a multimedia gateway for mobile devices

Science.gov (United States)

Hens, Raf; Goeminne, Nico; Van Hoecke, Sofie; Verdickt, Tom; Bouve, Thomas; Gielen, Frank; Demeester, Piet

2005-03-01

Although mobile users are currently offered a lot more capabilities on their mobile devices, they still experience some limitations. They can surf the Internet, read their e-mail and receive MMS messages, but they have limited processing power, storage capacity and bandwidth and are limited in their access to peripherals (e.g. printers). We have designed and implemented a multimedia gateway for mobile devices that reduces these limitations. It gives the mobile devices transparent access to high capacity devices connected to the gateway, which is built around a central, modularly extensible server that can run on any PC or home gateway. It manages two sets of modules: one set offering the actual services and another set handling the IP-based wireless interaction with the client applications on the mobile devices. These modules can be added and removed dynamically, offering new services on the fly. Currently services for storage, printing, domotics and playing music are provided. Others can easily be added later on. This paper discusses the architecture and development, the management of modules, the actual services and their benefits. Besides a proprietary implementation, it also looks into OSGi and how both platforms compare to each other, concerning design, architecture, ease of development, functionality, ...

Flexible feature interface for multimedia sources

Science.gov (United States)

Coffland, Douglas R [Livermore, CA

2009-06-09

A flexible feature interface for multimedia sources system that includes a single interface for the addition of features and functions to multimedia sources and for accessing those features and functions from remote hosts. The interface utilizes the export statement: export "C" D11Export void FunctionName(int argc, char ** argv,char * result, SecureSession *ctrl) or the binary equivalent of the export statement.

Intelligent Multi-Media Integrated Interface Project

Science.gov (United States)

1990-06-01

been devoted to the application of aritificial intelligence technology to the development of human -computer interface technology that integrates speech...RADC-TR-90-128 Final Technical Report June 1090 AD-A225 973 INTELLIGENT MULTI-MEDIA INTEGRATED INTERFACE PROJECT Calspan-University of Buffalo...contractual obligations or notices on a specific document require that it be returned. INTELLIGENT MULTI-MEDIA INTEGRATED INTERFACE PROJECT J. G. Neal J. M

Wireless device monitoring methods, wireless device monitoring systems, and articles of manufacture

Science.gov (United States)

McCown, Steven H [Rigby, ID; Derr, Kurt W [Idaho Falls, ID; Rohde, Kenneth W [Idaho Falls, ID

2012-05-08

Wireless device monitoring methods, wireless device monitoring systems, and articles of manufacture are described. According to one embodiment, a wireless device monitoring method includes accessing device configuration information of a wireless device present at a secure area, wherein the device configuration information comprises information regarding a configuration of the wireless device, accessing stored information corresponding to the wireless device, wherein the stored information comprises information regarding the configuration of the wireless device, comparing the device configuration information with the stored information, and indicating the wireless device as one of authorized and unauthorized for presence at the secure area using the comparing.

Adaptive Demand-Driven Multicast Routing in Multi-Hop Wireless Ad Hoc Networks

National Research Council Canada - National Science Library

Jetcheva, Jorjeta G

2004-01-01

...) nodes that wish to communicate. Each node in the ad hoc network acts as a router and forwards packets on behalf of other nodes, allowing nodes that are not within wireless range of each other to communicate over multi-hop paths...

Using multimedia to enhance the consent process for bunion correction surgery.

Science.gov (United States)

Batuyong, Eldridge D; Jowett, Andrew J L; Wickramasinghe, Nilmini; Beischer, Andrew D

2014-04-01

Obtaining informed consent from patients considering bunion surgery can be challenging. This study assessed the efficacy of a multimedia technology as an adjunct to the informed consent process. A prospective, cohort study was conducted involving 55 patients (7 males, 48 females) who underwent a standardized verbal discussion regarding bunion correction surgery followed by completion of a knowledge questionnaire. A multimedia educational program was then administered and the knowledge questionnaire repeated. Additional supplementary questions were then given regarding satisfaction with the multimedia program. Patients answered 74% questions correctly before the multimedia module compared with 94% after it (P multimedia tool performed as well as the treating surgeon. Multimedia technology is useful in enhancing patient knowledge regarding bunion surgery for the purposes of obtaining informed consent.

Utilization of Multimedia Laboratory: An Acceptance Analysis using TAM

Science.gov (United States)

Modeong, M.; Palilingan, V. R.

2018-02-01

Multimedia is often utilized by teachers to present a learning materials. Learning that delivered by multimedia enables people to understand the information of up to 60% of the learning in general. To applying the creative learning to the classroom, multimedia presentation needs a laboratory as a space that provides multimedia needs. This study aims to reveal the level of student acceptance on the multimedia laboratories, by explaining the direct and indirect effect of internal support and technology infrastructure. Technology Acceptance Model (TAM) is used as the basis of measurement on this research, through the perception of usefulness, ease of use, and the intention, it’s recognized capable of predicting user acceptance about technology. This study used the quantitative method. The data analysis using path analysis that focuses on trimming models, it’s performed to improve the model of path analysis structure by removing exogenous variables that have insignificant path coefficients. The result stated that Internal Support and Technology Infrastructure are well mediated by TAM variables to measure the level of technology acceptance. The implications suggest that TAM can measure the success of multimedia laboratory utilization in Faculty of Engineering UNIMA.

Multimedia watermarking techniques and applications

CERN Document Server

Kirovski, Darko

2006-01-01

Intellectual property owners must continually exploit new ways of reproducing, distributing, and marketing their products. However, the threat of piracy looms as a major problem with digital distribution and storage technologies. Multimedia Watermarking Techniques and Applications covers all current and future trends in the design of modern systems that use watermarking to protect multimedia content. Containing the works of contributing authors who are worldwide experts in the field, this volume is intended for researchers and practitioners, as well as for those who want a broad understanding

First International Conference Multimedia Processing, Communication and Computing Applications

CERN Document Server

Guru, Devanur

2013-01-01

ICMCCA 2012 is the first International Conference on Multimedia Processing, Communication and Computing Applications and the theme of the Conference is chosen as ‘Multimedia Processing and its Applications’. Multimedia processing has been an active research area contributing in many frontiers of today’s science and technology. This book presents peer-reviewed quality papers on multimedia processing, which covers a very broad area of science and technology. The prime objective of the book is to familiarize readers with the latest scientific developments that are taking place in various fields of multimedia processing and is widely used in many disciplines such as Medical Diagnosis, Digital Forensic, Object Recognition, Image and Video Analysis, Robotics, Military, Automotive Industries, Surveillance and Security, Quality Inspection, etc. The book will assist the research community to get the insight of the overlapping works which are being carried out across the globe at many medical hospitals and instit...

Visual Enhancements: Improving Deaf Students' Transition Skills Using Multimedia Technology.

Science.gov (United States)

Davis, Cheryl D.

1999-01-01

Discusses developments in technology that provide high-quality visual access to transition information and multimedia instruction for learners with deafness. Identifies a variety of considerations in using multimedia products and describes the pros and cons of different media in the context of several multimedia projects. (Author/CR)

Multimedia for occupational safety and health training: a pilot study examining a multimedia learning theory.

Science.gov (United States)

Wallen, Erik S; Mulloy, Karen B

2006-10-01

Occupational diseases are a significant problem affecting public health. Safety training is an important method of preventing occupational illness. Training is increasingly being delivered by computer although theories of learning from computer-based multimedia have been tested almost entirely on college students. This study was designed to determine whether these theories might also be applied to safety training applications for working adults. Participants viewed either computer-based multimedia respirator use training with concurrent narration, narration prior to the animation, or unrelated safety training. Participants then took a five-item transfer test which measured their ability to use their knowledge in new and creative ways. Participants who viewed the computer-based multimedia trainings both did significantly better than the control group on the transfer test. The results of this pilot study suggest that design guidelines developed for younger learners may be effective for training workers in occupational safety and health although more investigation is needed.

Multimedia Image Technology and Computer Aided Manufacturing Engineering Analysis

Science.gov (United States)

Nan, Song

2018-03-01

Since the reform and opening up, with the continuous development of science and technology in China, more and more advanced science and technology have emerged under the trend of diversification. Multimedia imaging technology, for example, has a significant and positive impact on computer aided manufacturing engineering in China. From the perspective of scientific and technological advancement and development, the multimedia image technology has a very positive influence on the application and development of computer-aided manufacturing engineering, whether in function or function play. Therefore, this paper mainly starts from the concept of multimedia image technology to analyze the application of multimedia image technology in computer aided manufacturing engineering.

A low-cost biomedical signal transceiver based on a Bluetooth wireless system.

Science.gov (United States)

Fazel-Rezai, Reza; Pauls, Mark; Slawinski, David

2007-01-01

Most current wireless biomedical signal transceivers use range-limiting communication. This work presents a low-cost biomedical signal transceiver that uses Bluetooth wireless technology. The design is implemented in a modular form to be adaptable to different types of biomedical signals. The signal front end obtains and processes incoming signals, which are then transmitted via a microcontroller and wireless module. Near real-time receive software in LabVIEW was developed to demonstrate the system capability. The completed transmitter prototype successfully transmits ECG signals, and is able to simultaneously send multiple signals. The sampling rate of the transmitter is fast enough to send up to thirteen ECG signals simultaneously, with an error rate below 0.1% for transmission exceeding 65 meters. A low-cost wireless biomedical transceiver has many applications, such as real-time monitoring of patients with a known condition in non-clinical settings.

Embedded RFID Recorder in short-range wireless devices

DEFF Research Database (Denmark)

2010-01-01

range communication devices. The problem is solved in that the portable communications device comprises a wireless communications interface for communicating with another device, a memory and an RFID-recorder for receiving an RFID-signal transmitted from an RFID-interrogator, wherein the device...... is adapted for storing individual received RFID-signals in the memory. An advantage of the invention is that it provides a relatively simple scheme for extracting information from a current environment of a portable communications device. The invention may e.g. be used for adapting listening devices, e...

Multimedia Visualizer: An Animated, Object-Based OPAC.

Science.gov (United States)

Lee, Newton S.

1991-01-01

Describes the Multimedia Visualizer, an online public access catalog (OPAC) that uses animated visualizations to make it more user friendly. Pictures of the system are shown that illustrate the interactive objects that patrons can access, including card catalog drawers, librarian desks, and bookshelves; and access to multimedia items is described.…

SmartMIMO: An Energy-Aware Adaptive MIMO-OFDM Radio Link Control for Next-Generation Wireless Local Area Networks

Directory of Open Access Journals (Sweden)

Wim Dehaene

2007-12-01

Full Text Available Multiantenna systems and more particularly those operating on multiple input and multiple output (MIMO channels are currently a must to improve wireless links spectrum efficiency and/or robustness. There exists a fundamental tradeoff between potential spectrum efficiency and robustness increase. However, multiantenna techniques also come with an overhead in silicon implementation area and power consumption due, at least, to the duplication of part of the transmitter and receiver radio front-ends. Although the area overhead may be acceptable in view of the performance improvement, low power consumption must be preserved for integration in nomadic devices. In this case, it is the tradeoff between performance (e.g., the net throughput on top of the medium access control layer and average power consumption that really matters. It has been shown that adaptive schemes were mandatory to avoid that multiantenna techniques hamper this system tradeoff. In this paper, we derive smartMIMO: an adaptive multiantenna approach which, next to simply adapting the modulation and code rate as traditionally considered, decides packet-per-packet, depending on the MIMO channel state, to use either space-division multiplexing (increasing spectrum efficiency, space-time coding (increasing robustness, or to stick to single-antenna transmission. Contrarily to many of such adaptive schemes, the focus is set on using multiantenna transmission to improve the link energy efficiency in real operation conditions. Based on a model calibrated on an existing reconfigurable multiantenna transceiver setup, the link energy efficiency with the proposed scheme is shown to be improved by up to 30% when compared to nonadaptive schemes. The average throughput is, on the other hand, improved by up to 50% when compared to single-antenna transmission.

SmartMIMO: An Energy-Aware Adaptive MIMO-OFDM Radio Link Control for Next-Generation Wireless Local Area Networks

Directory of Open Access Journals (Sweden)

Dehaene Wim

2007-01-01

Full Text Available Multiantenna systems and more particularly those operating on multiple input and multiple output (MIMO channels are currently a must to improve wireless links spectrum efficiency and/or robustness. There exists a fundamental tradeoff between potential spectrum efficiency and robustness increase. However, multiantenna techniques also come with an overhead in silicon implementation area and power consumption due, at least, to the duplication of part of the transmitter and receiver radio front-ends. Although the area overhead may be acceptable in view of the performance improvement, low power consumption must be preserved for integration in nomadic devices. In this case, it is the tradeoff between performance (e.g., the net throughput on top of the medium access control layer and average power consumption that really matters. It has been shown that adaptive schemes were mandatory to avoid that multiantenna techniques hamper this system tradeoff. In this paper, we derive smartMIMO: an adaptive multiantenna approach which, next to simply adapting the modulation and code rate as traditionally considered, decides packet-per-packet, depending on the MIMO channel state, to use either space-division multiplexing (increasing spectrum efficiency, space-time coding (increasing robustness, or to stick to single-antenna transmission. Contrarily to many of such adaptive schemes, the focus is set on using multiantenna transmission to improve the link energy efficiency in real operation conditions. Based on a model calibrated on an existing reconfigurable multiantenna transceiver setup, the link energy efficiency with the proposed scheme is shown to be improved by up to 30% when compared to nonadaptive schemes. The average throughput is, on the other hand, improved by up to 50% when compared to single-antenna transmission.

The Short-term Effects of ASPIRA: A Web-based, Multimedia Smoking Prevention Program for Adolescents in Romania: A Cluster Randomized Trial.

Science.gov (United States)

Nădăşan, Valentin; Foley, Kristie L; Pénzes, Melinda; Paulik, Edit; Mihăicuţă, Ștefan; Ábrám, Zoltán; Bálint, Jozsef; Csibi, Monika; Urbán, Robert

2017-08-01

Although web-based, multimedia smoking prevention programs have been tested in several high-income countries, their efficacy in Central and Eastern Europe is unknown. The aim of this trial was to assess the short-term effects of ASPIRA, among Romanian and Hungarian speaking ninth graders in Tirgu Mures, Romania. ASPIRA is the Romanian acronym for the translated and adapted version of ASPIRE, "A Smoking Prevention Interactive Experience," an evidence-based smoking prevention program originally developed to prevent tobacco use among high school students in the United States. Sixteen high schools in Tirgu Mures, Romania were randomized to receive five weekly sessions of the ASPIRA web-based, multimedia program or to a control condition. Socio-demographic data, psychosocial characteristics, and smoking behavior were collected from students at baseline and at 6 months. A hierarchical logistic regression analysis was conducted to test the efficacy of the intervention on smoking initiation and current smoking among 1369 students. Never-smoker students in the intervention arm were 35% less likely to report smoking initiation 6 months after the baseline assessment (OR = 0.65, 95%CI: 0.44-0.97). Reduced smoking initiation was observed most notably among students who were exposed to at least 75% of the ASPIRA program. There was no statistically significant effect of the intervention on current tobacco use (OR = 0.80, 95%CI: 0.44-1.46). ASPIRA, an adapted version of the evidence-based, multimedia ASPIRE program that was originally developed and tested in the United States may decrease smoking initiation among multi-ethnic adolescents in Central and Eastern Europe. (1). Web-based, multimedia smoking prevention programs may be effective tools to prevent smoking initiation among multi-ethnic adolescent communities in Central and Eastern Europe. (2). The degree of exposure is critical, only high exposure to the multimedia smoking prevention program is associated with reduced

CRISP : a scalable VLIW processor for low power multimedia systems

NARCIS (Netherlands)

Barat Quesada, F.

2005-01-01

Over the last couple of years, the demand for portable multimedia devices has been growing at an impressive rate. The ideal multimedia device will present high quality multimedia content, and will be networked, portable, inexpensive and easy to use. In order to cope with the dynamism of current and

Performance Evaluation and Parameter Optimization of SoftCast Wireless Video Broadcast

Directory of Open Access Journals (Sweden)

Dongxue Yang

2015-08-01

Full Text Available Wireless video broadcast plays an imp ortant role in multimedia communication with the emergence of mobile video applications. However, conventional video broadcast designs suffer from a cliff effect due to separated source and channel encoding. The newly prop osed SoftCast scheme employs a cross-layer design, whose reconstructed video quality is prop ortional to the channel condition. In this pap er, we provide the p erformance evaluation and the parameter optimization of the SoftCast system. Optimization principles on parameter selection are suggested to obtain a b etter video quality, o ccupy less bandwidth and/or utilize lower complexity. In addition, we compare SoftCast with H.264 in the LTE EPA scenario. The simulation results show that SoftCast provides a b etter p erformance in the scalability to channel conditions and the robustness to packet losses.

A Technical Evaluation of Wireless Connectivity from Patient Monitors to an Anesthesia Information Management System During Intensive Care Unit Surgery.

Science.gov (United States)

Simpao, Allan F; Galvez, Jorge A; England, W Randall; Wartman, Elicia C; Scott, James H; Hamid, Michael M; Rehman, Mohamed A; Epstein, Richard H

2016-02-01

Surgical procedures performed at the bedside in the neonatal intensive care unit (NICU) at The Children's Hospital of Philadelphia were documented using paper anesthesia records in contrast to the operating rooms, where an anesthesia information management system (AIMS) was used for all cases. This was largely because of logistical problems related to connecting cables between the bedside monitors and our portable AIMS workstations. We implemented an AIMS for documentation in the NICU using wireless adapters to transmit data from bedside monitoring equipment to a portable AIMS workstation. Testing of the wireless AIMS during simulation in the presence of an electrosurgical generator showed no evidence of interference with data transmission. Thirty NICU surgical procedures were documented via the wireless AIMS. Two wireless cases exhibited brief periods of data loss; one case had an extended data gap because of adapter power failure. In comparison, in a control group of 30 surgical cases in which wired connections were used, there were no data gaps. The wireless AIMS provided a simple, unobtrusive, portable alternative to paper records for documenting anesthesia records during NICU bedside procedures.

Demand for Multimedia in the Classroom

OpenAIRE

Boyer, Tracy A.; Briggeman, Brian C.; Norwood, F. Bailey

2009-01-01

This study elicits preferences for multimedia in the classroom for students and faculty members in agricultural economics. Employing an Internet-based conjoint ranking survey, the results show that students prefer multimedia instructional tools over a traditional chalkboard/whiteboard lecture format while faculty members do not. Neither students nor faculty members are enthusiastic about electronic textbooks, and students will accept them only if they save $80. Finally, preferences for multim...

Authoring multimedia in the CMIF environment

OpenAIRE

Hardman, Lynda; Rossum, Guido; Bulterman, Dick

1993-01-01

textabstractWe present the user interface to the CMIF authoring environment for constructing and playing multimedia presentations. Within the environment an author constructs a presentation in terms of its structure and additional synchronization constraints, from which the actual timing information is derived. The CMIF authoring environment presents three main views of a multimedia presentation: a hierarchy view for manipulating and viewing a presentation’s hierarchical structure; a channel ...

Multimedia Transformation: A Special Report on Multimedia in Schools

Science.gov (United States)

Education Week, 2011

2011-01-01

In science and math classes across the country, digital tools are being used to conduct experiments, analyze data, and run 3-D simulations to explain complex concepts. Language arts teachers are now pushing the definition of literacy to include the ability to express ideas through media. This report, "Multimedia Transformation," examines the many…

Wireless mesh networks.

Science.gov (United States)

Wang, Xinheng

2008-01-01

Wireless telemedicine using GSM and GPRS technologies can only provide low bandwidth connections, which makes it difficult to transmit images and video. Satellite or 3G wireless transmission provides greater bandwidth, but the running costs are high. Wireless networks (WLANs) appear promising, since they can supply high bandwidth at low cost. However, the WLAN technology has limitations, such as coverage. A new wireless networking technology named the wireless mesh network (WMN) overcomes some of the limitations of the WLAN. A WMN combines the characteristics of both a WLAN and ad hoc networks, thus forming an intelligent, large scale and broadband wireless network. These features are attractive for telemedicine and telecare because of the ability to provide data, voice and video communications over a large area. One successful wireless telemedicine project which uses wireless mesh technology is the Emergency Room Link (ER-LINK) in Tucson, Arizona, USA. There are three key characteristics of a WMN: self-organization, including self-management and self-healing; dynamic changes in network topology; and scalability. What we may now see is a shift from mobile communication and satellite systems for wireless telemedicine to the use of wireless networks based on mesh technology, since the latter are very attractive in terms of cost, reliability and speed.

Interactive multimedia consent for biobanking: a randomized trial.

Science.gov (United States)

Simon, Christian M; Klein, David W; Schartz, Helen A

2016-01-01

The potential of interactive multimedia to improve biobank informed consent has yet to be investigated. The aim of this study was to test the separate effectiveness of interactivity and multimedia at improving participant understanding and confidence in understanding of informed consent compared with a standard, face-to-face (F2F) biobank consent process. A 2 (face-to-face versus multimedia) × 2 (standard versus enhanced interactivity) experimental design was used with 200 patients randomly assigned to receive informed consent. All patients received the same information provided in the biobank's nine-page consent document. Interactivity (F(1,196) = 7.56, P = 0.007, partial η(2) = 0.037) and media (F(1,196) = 4.27, P = 0.04, partial η(2) = 0.021) independently improved participants' understanding of the biobank consent. Interactivity (F(1,196) = 6.793, P = 0.01, partial η(2) = 0.033), but not media (F(1,196) = 0.455, not significant), resulted in increased participant confidence in their understanding of the biobank's consent materials. Patients took more time to complete the multimedia condition (mean = 18.2 min) than the face-to-face condition (mean = 12.6 min). This study demonstrated that interactivity and multimedia each can be effective at promoting an individual's understanding and confidence in their understanding of a biobank consent, albeit with additional time investment. Researchers should not assume that multimedia is inherently interactive, but rather should separate the two constructs when studying electronic consent.

A Framework for Narration and Learning in Educational Multimedia

DEFF Research Database (Denmark)

Mosegaard, Jesper; Bennedsen, Jens

2003-01-01

In this article we describe a multimedia adventure game framework for a learning environment to support the teaching and learning of introductory programming. In the framework we have conceptualized two important aspects of such an environment: narration and learning topics. We describe...... the interplay between these aspects and how the framework utilizes this to adapt the learning process to the individual student. The motivation for the separation is to help the teacher balance the two main driving forces of an edutainment product: entertainment and learning. It is the responsibility...... of the teacher to define the range of stories and topics using the framework. The framework provides a complete learning environment where the teacher merely needs to define the content....

Using Selective Redundancy and Testing to Optimize Learning from Multimedia Lessons

OpenAIRE

Yue, Carole Leigh

2014-01-01

Multimedia learning refers to learning from a combination of words and images. In the present dissertation, a multimedia lesson is defined as an animated, narrated educational video that depicts a scientific process--a format of instructional material becoming increasingly common in online, hybrid, and traditional classrooms. The overarching goal of the present research was to investigate how to optimize learning from multimedia lessons using two related theories of multimedia learning (the...

A Trace-Driven Analysis of Wireless Group Communication Mechanisms

Directory of Open Access Journals (Sweden)

Surendar Chandra

2012-08-01

Full Text Available Wireless access is increasingly ubiquitous while mobile devices that use them are resource rich. These trends allow wireless users to collaborate with each other. We investigate various group communication paradigms that underly collaboration applications. We synthesize durations when members collaborate using wireless device availability traces. Wireless users operate from a variety of locations. Hence, we analyzed the behavior of wireless users in universities, corporations, conference venues, and city-wide hotspots. We show that the availability durations are longer in corporations followed by university and then in hotspots. The number of simultaneously available wireless users is small in all the scenarios. The session lengths are becoming smaller while the durations between sessions are becoming larger. We observed user churn in all the scenarios. We show that synchronous mechanisms require less effort to maintain update synchronicity among the group members. However, distributed mechanisms require a large number of replicas in order to propagate updates among the users. For asynchronous mechanisms, we show that pull-based mechanisms naturally randomize the times when updates are propagated and thus achieve better performance than push based mechanisms.We develop an adaptive approach that customizes the update frequency using the last session duration and show that this mechanism exhibits good performance when the required update frequency intervals are large. We also show that for a given number of gossips, it is preferable to propagate updates to all available nodes rather than increasing the frequency while correspondingly reducing the number of nodes to propagate updates.We develop a middleware to illustrate the practicality of our approach.

Smartphone Household Wireless Electroencephalogram Hat

Directory of Open Access Journals (Sweden)

Harold Szu

2013-01-01

Full Text Available Rudimentary brain machine interface has existed for the gaming industry. Here, we propose a wireless, real-time, and smartphone-based electroencephalogram (EEG system for homecare applications. The system uses high-density dry electrodes and compressive sensing strategies to overcome conflicting requirements between spatial electrode density, temporal resolution, and spatiotemporal throughput rate. Spatial sparseness is addressed by close proximity between active electrodes and desired source locations and using an adaptive selection of N active among 10N passive electrodes to form m-organized random linear combinations of readouts, m≪N≪10N. Temporal sparseness is addressed via parallel frame differences in hardware. During the design phase, we took tethered laboratory EEG dataset and applied fuzzy logic to compute (a spatiotemporal average of larger magnitude EEG data centers in 0.3 second intervals and (b inside brainwave sources by Independent Component Analysis blind deconvolution without knowing the impulse response function. Our main contributions are the fidelity of quality wireless EEG data compared to original tethered data and the speed of compressive image recovery. We have compared our recovery of ill-posed inverse data against results using Block Sparse Code. Future work includes development of strategies to filter unwanted artifact from high-density EEGs (i.e., facial muscle-related events and wireless environmental electromagnetic interferences.

Wireless virtualization

CERN Document Server

Wen, Heming; Le-Ngoc, Tho

2013-01-01

This SpringerBriefs is an overview of the emerging field of wireless access and mobile network virtualization. It provides a clear and relevant picture of the current virtualization trends in wireless technologies by summarizing and comparing different architectures, techniques and technologies applicable to a future virtualized wireless network infrastructure. The readers are exposed to a short walkthrough of the future Internet initiative and network virtualization technologies in order to understand the potential role of wireless virtualization in the broader context of next-generation ubiq

The place of experience, culture and multimedia learning in teacher training

Directory of Open Access Journals (Sweden)

Monica Fantin

2012-05-01

Full Text Available What are the challenges of training children, young people and teachers today? Speaking of knowledge and skills necessary for teachers to perform in current scenarios implies asking to what extent university degree courses and teacher training institutions are adapting to the new demands of education. By highlighting some current challenges of university education, this article emphasizes the importance of experience, cultural training and multimedia in teacher training, from a culturalistic perspective of media education. Considering that media education is a field under construction, the transversality and the contribution of multidisciplinary knowledge of science, education, communication and the arts are a “border-object”, an interface that can better interpret the current transformation of knowledge and the tools of digital culture which are not limited to school education. The text discusses the possibility of multimedia education and its skills, such as integration of knowledge and methodological contributions deriving from different areas of knowledge and from the perspective of multiple languages in school and culture. From this results the need to set up other spaces for thinking about educational and training praxis, discussing news forms of cultural mediation in contemporary settings of teachers training.

Resource Optimization in Distributed Real-Time Multimedia Applications

NARCIS (Netherlands)

Yang, R.; van der Mei, R.D.; Roubos, D.; Seinstra, F.J.; Bal, H.E.

2012-01-01

The research area of multimedia content analysis (MMCA) considers all aspects of the automated extraction of knowledge from multimedia archives and data streams. To adhere to strict time constraints, large-scalemultimedia applications typically are being executed on distributed systems consisting of

A Computer Adaptive Testing Version of the Addiction Severity Index-Multimedia Version (ASI-MV): The Addiction Severity CAT

Science.gov (United States)

Butler, Stephen F.; Black, Ryan A.; McCaffrey, Stacey A.; Ainscough, Jessica; Doucette, Ann M.

2017-01-01

The purpose of this study was to develop and validate a computer adaptive testing (CAT) version of the Addiction Severity Index-Multimedia Version (ASI-MV®), the Addiction Severity CAT. This goal was accomplished in four steps. First, new candidate items for Addiction Severity CAT domains were evaluated after brainstorming sessions with experts in substance abuse treatment. Next, this new item bank was psychometrically evaluated on a large non-clinical (n =4419) and substance abuse treatment sample (n =845). Based on these results, final items were selected and calibrated for the creation of the Addiction Severity CAT algorithms. Once the algorithms were developed for the entire assessment, a fully functioning prototype of an Addiction Severity CAT was created. CAT simulations were conducted and optimal termination criteria were selected for the Addiction Severity CAT algorithms. Finally, construct validity of the CAT algorithms was evaluated by examining convergent/discriminant validity and sensitivity to change. The Addiction Severity CAT was determined to be valid, sensitive to change, and reliable. Further, the Addiction Severity CAT’s time of administration was found to be significantly less than the average time of administration for the ASI-MV composite scores. This study represents the initial validation of an IRT-based Addiction Severity CAT, and further exploration of the Addiction Severity CAT is needed. PMID:28230387

A computer adaptive testing version of the Addiction Severity Index-Multimedia Version (ASI-MV): The Addiction Severity CAT.

Science.gov (United States)

Butler, Stephen F; Black, Ryan A; McCaffrey, Stacey A; Ainscough, Jessica; Doucette, Ann M

2017-05-01

The purpose of this study was to develop and validate a computer adaptive testing (CAT) version of the Addiction Severity Index-Multimedia Version (ASI-MV), the Addiction Severity CAT. This goal was accomplished in 4 steps. First, new candidate items for Addiction Severity CAT domains were evaluated after brainstorming sessions with experts in substance abuse treatment. Next, this new item bank was psychometrically evaluated on a large nonclinical (n = 4,419) and substance abuse treatment (n = 845) sample. Based on these results, final items were selected and calibrated for the creation of the Addiction Severity CAT algorithms. Once the algorithms were developed for the entire assessment, a fully functioning prototype of an Addiction Severity CAT was created. CAT simulations were conducted, and optimal termination criteria were selected for the Addiction Severity CAT algorithms. Finally, construct validity of the CAT algorithms was evaluated by examining convergent and discriminant validity and sensitivity to change. The Addiction Severity CAT was determined to be valid, sensitive to change, and reliable. Further, the Addiction Severity CAT's time of completion was found to be significantly less than the average time of completion for the ASI-MV composite scores. This study represents the initial validation of an Addiction Severity CAT based on item response theory, and further exploration of the Addiction Severity CAT is needed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Smart thermal patch for adaptive thermotherapy

KAUST Repository

Hussain, Muhammad Mustafa

2015-11-12

A smart thermal patch for adaptive thermotherapy is provided. In an embodiment, the patch can be a stretchable, non-polymeric, conductive thin film flexible and non-invasive body integrated mobile thermal heater with wireless control capabilities that can be used to provide adaptive thermotherapy. The patch can be geometrically and spatially tunable on various pain locations. Adaptability allows the amount of heating to be tuned based on the temperature of the treated portion.

Developing Modular and Adaptable Courseware Using TeachML.

Science.gov (United States)

Wehner, Frank; Lorz, Alexander

This paper presents the use of an XML grammar for two complementary projects--CHAMELEON (Cooperative Hypermedia Adaptive MultimEdia Learning Objects) and EIT (Enabling Informal Teamwork). Areas of applications are modular courseware documents and the collaborative authoring process of didactical units. A number of requirements for a suitable…

Adaptive object placement for augmented reality use in driver assistance systems

OpenAIRE

Bordes, Lucie; Breckon, Toby P.; Katramados, Ioannis; Kheyrollahi, Alireza

2011-01-01

We present an approach for adaptive object placement for Augmented Reality (AR) use in driver assistance systems. Combined vanishing point and road surface detection enable the real-time adaptive emplacement of AR objects within a drivers' natural field of view for on-road information display. This work combines both automotive vision and multimedia production aspects of real-time visual engineering.

Wireless Biological Electronic Sensors.

Science.gov (United States)

Cui, Yue

2017-10-09

The development of wireless biological electronic sensors could open up significant advances for both fundamental studies and practical applications in a variety of areas, including medical diagnosis, environmental monitoring, and defense applications. One of the major challenges in the development of wireless bioelectronic sensors is the successful integration of biosensing units and wireless signal transducers. In recent years, there are a few types of wireless communication systems that have been integrated with biosensing systems to construct wireless bioelectronic sensors. To successfully construct wireless biological electronic sensors, there are several interesting questions: What types of biosensing transducers can be used in wireless bioelectronic sensors? What types of wireless systems can be integrated with biosensing transducers to construct wireless bioelectronic sensors? How are the electrical sensing signals generated and transmitted? This review will highlight the early attempts to address these questions in the development of wireless biological electronic sensors.

The four facets of multimedia streaming (Chapter 7)

NARCIS (Netherlands)

Agboma, F.; Liotta, A.; Pierre, S.

2010-01-01

Recent advances in media coding techniques and network access technologies have made multimedia streaming practicable and affordable in both fixed and mobile environments. Multimedia streaming services from anywhere and at anytime is fast becoming a reality. This chapter provides a snapshot of the

Optical power allocation for adaptive transmissions in wavelength-division multiplexing free space optical networks

Directory of Open Access Journals (Sweden)

Hui Zhou

2015-08-01

Full Text Available Attracting increasing attention in recent years, the Free Space Optics (FSO technology has been recognized as a cost-effective wireless access technology for multi-Gigabit rate wireless networks. Radio on Free Space Optics (RoFSO provides a new approach to support various bandwidth-intensive wireless services in an optical wireless link. In an RoFSO system using wavelength-division multiplexing (WDM, it is possible to concurrently transmit multiple data streams consisting of various wireless services at very high rate. In this paper, we investigate the problem of optical power allocation under power budget and eye safety constraints for adaptive WDM transmission in RoFSO networks. We develop power allocation schemes for adaptive WDM transmissions to combat the effect of weather turbulence on RoFSO links. Simulation results show that WDM RoFSO can support high data rates even over long distance or under bad weather conditions with an adequate system design.

Global and site specific multimedia (field) studies

International Nuclear Information System (INIS)

Cutshall, N.H.; Guerin, M.R.

1987-01-01

Experience with radioactive fallout, with organic contaminants and with heavy metals has amply demonstrated that cross-media transfers are common and that understanding the transport, cycling, and fate of these contaminants requires a multimedia approach. Nonetheless, pollutants with similar physical and chemical attributes may follow markedly different pathways. The frequency of exceptions to predictions based on simplistic models is also sufficient to show that direct investigation of environmental contamination is essential to confirm validity of models used for conceptualizing a problem or for control. Modeling based on multimedia premises and regulatory controls that encompass multimedia considerations are challenged by a dilemma, however. First, the development of multimedia models or regulatory frameworks represents simplification and generalization. This is true for several reasons: (1) inadequate understanding of physical and environmental factors which control specific cross-media transfer; (2) the absence of specific data on certain multimedia pollutant concentrations; (3) even the most powerful computers do not have sufficient speed and capacity to deal with the known complexities of natural systems. On the other hand, for contaminants such as mercury, it may be necessary to include great detail; the overall distribution in the environment may be less important than the rate of some minor process. With sufficient experience and good judgment of what can be ignored, the simplifications and generalizations can be made. For the present, and for the foreseeable future, however, they absolutely must be accompanied by thorough field validation and monitoring

A Data Gathering Scheme in Wireless Sensor Networks Based on Synchronization of Chaotic Spiking Oscillator Networks

International Nuclear Information System (INIS)

Nakano, Hidehiro; Utani, Akihide; Miyauchi, Arata; Yamamoto, Hisao

2011-01-01

This paper studies chaos-based data gathering scheme in multiple sink wireless sensor networks. In the proposed scheme, each wireless sensor node has a simple chaotic oscillator. The oscillators generate spike signals with chaotic interspike intervals, and are impulsively coupled by the signals via wireless communication. Each wireless sensor node transmits and receives sensor information only in the timing of the couplings. The proposed scheme can exhibit various chaos synchronous phenomena and their breakdown phenomena, and can effectively gather sensor information with the significantly small number of transmissions and receptions compared with the conventional scheme. Also, the proposed scheme can flexibly adapt various wireless sensor networks not only with a single sink node but also with multiple sink nodes. This paper introduces our previous works. Through simulation experiments, we show effectiveness of the proposed scheme and discuss its development potential.

PENGEMBANGAN MULTIMEDIA BERBASIS MASALAH UNTUK MENINGKATKAN MOTIVASI BELAJAR DAN KEMAMPUAN BERPIKIR KRITIS SISWA

Directory of Open Access Journals (Sweden)

Dwi Septiana Sari

2015-10-01

Full Text Available Penelitian ini bertujuan untuk: (1 mengembangkan multimedia berbasis masalah dengan materi redoks, (2 menganalisis kualitas multimedia berbasis masalah, serta (3 menguji keefektifan multimedia berbasis masalah dalam meningkatkan motivasi belajar dan kemampuan berpikir kritis peserta didik. Penelitian ini termasuk dalam penelitian dan pengembangan berdasarkan model Borg & Gall. Subjek uji coba dalam penelitian ini meliputi peserta didik kelas X SMA Negeri 6 Yogyakarta. Data dikumpulkan melalui angket untuk validasi media, lembar observasi keterlaksanaan pembelajaran, lembar observasi motivasi belajar, angket motivasi belajar, dan tes kemampuan berpikir kritis. Hasil penelitian menunjukkan bahwa (1 pengembangan multimedia berbasis masalah materi redoks dilaksanakan sesuai dengan prosedur pengembangan, (2 secara umum kualitas multimedia berbasis masalah termasuk dalam kategori sangat baik, dan (3 multimedia berbasis masalah efektif untuk meningkatkan motivasi belajar dan kemampuan berpikir kritis peserta didik pada pembelajaran materi redoks. Kata kunci: multimedia berbasis masalah, motivasi belajar, kemampuan berpikir kritis.   DEVELOPING MULTIMEDIA BASED ON PROBLEM TO INCREASE STUDENT’S LEARNING MOTIVATION AND CRITICAL THINKING SKILL Abstract The aims of this research are (1 developing the multimedia based on problem in redox’s chapter, (2 analysing the quality of multimedia based on problem, and (3 testing the effectiveness of multimedia based on problem in increasing student’s learning motivation and critical thinking skill. This research used Borg & Gall research and development’s model. The subject of the research is the grade X students of SMA Negeri 6 Yogyakarta. The data were collected by using media validation’s questionnaire, learning process observation sheet, learning motivation’s questionnaire and obser-vation sheet, and critical thinking skill’s test. The results of the research show that (1 the development of

An Energy-Efficient Underground Localization System Based on Heterogeneous Wireless Networks

Science.gov (United States)

Yuan, Yazhou; Chen, Cailian; Guan, Xinping; Yang, Qiuling

2015-01-01

A precision positioning system with energy efficiency is of great necessity for guaranteeing personnel safety in underground mines. The location information of the miners' should be transmitted to the control center timely and reliably; therefore, a heterogeneous network with the backbone based on high speed Industrial Ethernet is deployed. Since the mobile wireless nodes are working in an irregular tunnel, a specific wireless propagation model cannot fit all situations. In this paper, an underground localization system is designed to enable the adaptation to kinds of harsh tunnel environments, but also to reduce the energy consumption and thus prolong the lifetime of the network. Three key techniques are developed and implemented to improve the system performance, including a step counting algorithm with accelerometers, a power control algorithm and an adaptive packets scheduling scheme. The simulation study and experimental results show the effectiveness of the proposed algorithms and the implementation. PMID:26016918

Creativity In Amateur Multimedia: Popular Culture, Critical Theory, And Hci

Directory of Open Access Journals (Sweden)

Jeffrey Bardzell

2007-01-01

Full Text Available The last decade has witnessed the emergence and aesthetic maturation of amateur multimedia on an unprecedented scale, from video podcasts to machinima, and Flash animations to user-created metaverses. Today, especially in academic circles, this pop culture phenomenon is little recognized and even less understood. This paper explores creativity in amateur multimedia using three theorizations of creativity—those of HCI, postructuralism, and technological determinism. These theorizations frame a semiotic analysis of numerous commonly used multimedia authoring platforms, which demonstrates a deep convergence of multimedia authoring tool strategies that collectively project a conceptualization and practice of digital creativity. This conceptualization of digital creativity in authoring tools is then compared with hundreds of amateur-created artifacts. These analyses reveal relationships among emerging amateur multimedia aesthetics, common software authoring tools, and the three theorizations of creativity discussed.

A Hybrid Data Compression Scheme for Power Reduction in Wireless Sensors for IoT.

Science.gov (United States)

Deepu, Chacko John; Heng, Chun-Huat; Lian, Yong

2017-04-01

This paper presents a novel data compression and transmission scheme for power reduction in Internet-of-Things (IoT) enabled wireless sensors. In the proposed scheme, data is compressed with both lossy and lossless techniques, so as to enable hybrid transmission mode, support adaptive data rate selection and save power in wireless transmission. Applying the method to electrocardiogram (ECG), the data is first compressed using a lossy compression technique with a high compression ratio (CR). The residual error between the original data and the decompressed lossy data is preserved using entropy coding, enabling a lossless restoration of the original data when required. Average CR of 2.1 × and 7.8 × were achieved for lossless and lossy compression respectively with MIT/BIH database. The power reduction is demonstrated using a Bluetooth transceiver and is found to be reduced to 18% for lossy and 53% for lossless transmission respectively. Options for hybrid transmission mode, adaptive rate selection and system level power reduction make the proposed scheme attractive for IoT wireless sensors in healthcare applications.

Let's talk about it: dialogues with multimedia databases Database support for human activity

NARCIS (Netherlands)

de Vries, A.P.; van der Veer, Gerrit C.; Blanken, Henk

We describe two scenarios of user tasks in which access to multimedia data plays a significant role. Because current multimedia databases cannot support these tasks, we introduce three new requirements on multimedia databases: multimedia objects should be active objects, querying is an interaction

Multimedia architectures: from desktop systems to portable appliances