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Wireless Technologies (wireless + technology)
Selected AbstractsWireless Technology in the Library: The RIT Experience: Overview of the ProjectBULLETIN OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE & TECHNOLOGY (ELECTRONIC), Issue 5 2001Pat Pitkin Director of Libraries First page of article [source] Wireless Technology in the Library: The RIT Experience: Technical ConsiderationsBULLETIN OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE & TECHNOLOGY (ELECTRONIC), Issue 5 2001Michael Robertson Library Software Specialist No abstract is available for this article. [source] A survey of mobile and wireless technologies for augmented reality systemsCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 1 2008George Papagiannakis Abstract Recent advances in hardware and software for mobile computing have enabled a new breed of mobile augmented reality (AR) systems and applications. A new breed of computing called ,augmented ubiquitous computing' has resulted from the convergence of wearable computing, wireless networking, and mobile AR interfaces. In this paper, we provide a survey of different mobile and wireless technologies and how they have impact AR. Our goal is to place them into different categories so that it becomes easier to understand the state of art and to help identify new directions of research. Copyright © 2008 John Wiley & Sons, Ltd. [source] Waiting for Broadband: Local Competition and the Spatial Distribution of Advanced Telecommunication Services in the United StatesGROWTH AND CHANGE, Issue 2 2004TONY H. GRUBESIC ABSTRACT With the passage of the Telecommunications Act of 1996, Congress directed the Federal Communications Commission and all fifty U.S. states to encourage the deployment of advanced telecommunication capability in a reasonable and timely manner. Today, with the rollout of advanced data services such as digital subscriber lines (xDSL), cable modems, and fixed wireless technologies, broadband has become an important component of telecommunication service and competition. Unfortunately, the deployment of last-mile infrastructure enabling high-speed access has proceeded more slowly than anticipated and competition in many areas is relatively sparse. More importantly, there are significant differences in the availability of broadband services between urban and rural areas. This paper explores aspects of broadband access as a function of market demand and provider competition. Data collected from the Federal Communications Commission is analyzed using a geographic information system and spatial statistical techniques. Results suggest significant spatial variation in broadband Internet access as a function of provider competition in the United States. [source] Empirical evaluation of receiver-based TCP delay control in CDMA2000 networksINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 8 2007Oh-keun Kwon Abstract Wide-area broadband wireless technologies such as CDMA2000 often suffer from variable transfer rate and long latency. In particular, TCP window-based rate control causes excessive buffering at the base station because of the lower transfer rate of the wireless link than that of the wired backhaul link. This performance characteristic of TCP further increases the end-to-end delay, and additional resources are required at the base station. This paper presents a practical mechanism to control the end-to-end TCP delay for CDMA2000 networks (or other similar wireless technologies). The key idea is to reduce and stabilize RTT (round-trip time) by dynamically controlling the TCP advertised window size, based on a runtime measurement of the wireless channel condition at the mobile station. The proposed system has been implemented by modifying the Linux protocol stack. The experiment results, conducted on a commercial CDMA2000 1x network, show that the proposed scheme greatly reduces the TCP delay in non-congested networks, while not sacrificing the TCP throughput in congested networks. Copyright © 2006 John Wiley & Sons, Ltd. [source] Fusion of digital television, broadband Internet and mobile communications,Part I: Enabling technologiesINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 4 2007F. L. C. Ong Abstract The introduction of digital video broadcasting (DVB) satellite systems has become an important tool for future mobile communication and is currently a focus in several research areas such as the integration of DVB satellite systems with different wireless technologies. This tutorial consists of two parts, Enabling technologies and Future service scenarios, which aims to provide an introduction to the current state-of-the-art of DVB standards over satellite and its fusion with mobile and Internet technologies. This paper, Enabling technologies, focuses on providing an overview of the different technologies and issues that facilitates better understanding of the current and future operational scenarios, whereas the second paper, Future service scenarios will emphasize future research directions in this research area. In the first part, the paper will initially be focused on the introduction of different DVB satellite systems, i.e. DVB- via satellite (DVB-S), DVB return channel by satellite (DVB-RCS) and second-generation DVB system for broadband satellite services (DVB-S2). This is then followed by a description of the different Internet Protocol (IP) technologies used to support macro- and micro-mobility and the migration strategies from IP version 4 (IPv4) to IP version 6 (IPv6). Finally, the different security mechanisms for the DVB system and end-to-end satellite network are addressed. Copyright © 2007 John Wiley & Sons, Ltd. [source] From anytime, anywhere to all-the-time, everywhere: Learning objects, broadband and wireless reshape digital libraries for learning and research.PROCEEDINGS OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE & TECHNOLOGY (ELECTRONIC), Issue 1 2003Sponsored by SIG STI Learning objects are among the latest types of materials to be included in digital libraries. These are small portions of lesson material designed to be used in multiple configurations for multiple instructional applications, ranging from distance learning to interactive simulation. As broadband and wireless technologies change the expectations and performance patterns of the user, learning objects change the nature of content and the way that it must be managed. The size and diversity of digital collections affect the options through which these materials can be accessed. Many libraries are offering wireless access to their networks and many individuals are accessing digital libraries off-site using broadband technologies. Each of these trends affects decisions made for collection development, portal design and network design, and those decisions dictate specific technological requirements for access. This panel session highlights management and infrastructure issues of digital libraries as they relate to learning objects, broadband and wireless technologies. [source] How Niqula Nasrallah Became John Jacob Astor: Syrian Emigrants Aboard the Titanic and the Materiality of LanguageJOURNAL OF LINGUISTIC ANTHROPOLOGY, Issue 2 2008Jess Bier In this article, I explore the physical afterlife of one victim of the 1912 Titanic disaster, the Syrian American businessman Niqula Nasrallah, whose remains would widely be identified as those of the famous multimillionaire John Jacob Astor. Syrian emigrants constituted 10,20 percent of the Titanic's third-class passengers, and their names were overwhelmingly altered as casualty lists were transmitted via an early form of radio. Such transformations only served to reinforce linguistic barriers, in direct contrast to widespread assertions that new technologies would enable instantaneous worldwide communication. A discussion of the substitution of Astor for Nasrallah thus allows insight into the production of confusion that resulted from the development of wireless technology as a linguistic medium.,[migration, technology, materiality of language, globalization, Lebanon, Syria] [source] Visible and invisible effects of hurricanes on forest ecosystems: an international reviewAUSTRAL ECOLOGY, Issue 4 2008A. E. LUGO Abstract Hurricanes have visible and invisible effects on forests. The visible effects are dramatic, noticeable over the short-term and relatively well documented in the literature. Invisible effects are less understood as they require well-focused research both in the short- and long-term time scales. This review of the literature on hurricane effects focuses on the Neotropics and the temperate zone of North America. The material is organized according to a heuristic model that distinguishes between immediate effects (0 to 3 years), immediate responses (0 to 20 years), trajectories of responses (0 to 100 years) and long-term legacies (>100 years). It is suggested that the ecological role of hurricanes involves six principal effects: 1. they change the ecological space available to organisms; 2. they set organisms in motion; 3. they increase the heterogeneity of the landscape and the variability in ecosystem processes; 4. they rejuvenate the landscape and its ecosystems and redirect succession; 5. they shape forest structure, influence their species composition and diversity and regulate their function; and 6. they induce evolutionary change through natural selection and ecological creativity through self-organization. A new approach to hurricane research will study hurricanes at the same scale at which they operate (i.e., across latitudes and longitudes and over disturbed and undisturbed landscapes). This research will require networks of observation platforms located along expected hurricane paths to facilitate forest structure and functioning observations across gradients of hurricane frequency and intensity. This research will also require use of remote sensing and automated wireless technology, hardened to survive hurricane-strength winds and floods to assure real time measurements of the characteristics of hurricanes and ecosystem responses. No progress will be forthcoming in the understanding of hurricane effects if we do not learn to quantify objectively the energy dissipation of hurricanes on the full grid of affected forests as the hurricane passes over a landscape. [source] Reactive oxygen species formation is not enhanced by exposure to UMTS 1950 MHz radiation and co-exposure to ferrous ions in Jurkat cellsBIOELECTROMAGNETICS, Issue 7 2009Francesca Brescia Abstract This study was designed to assess if radiofrequency (RF) radiation induces oxidative stress in cultured mammalian cells when given alone or in combination with ferrous ions (FeSO4). For this purpose the production of reactive oxygen species (ROS) was measured by flow cytometry in human lymphoblastoid cells exposed to 1950 MHz signal used by the third generation wireless technology of the Universal Mobile Telecommunication System (UMTS) at Specific Absorption Rate of 0.5 and 2.0 W/kg. Short (5,60 min) or long (24 h) duration exposures were carried out in a waveguide system under strictly controlled conditions of both dosimetry and environment. Cell viability was also measured after 24 h RF exposure using the Resazurin and Neutral Red assays. Several co-exposure protocols were applied to test if RF radiation is able to alter ROS formation induced by FeSO4 (RF given before or concurrently to FeSO4). The results obtained indicate that non-thermal RF exposures do not increase spontaneous ROS formation in any of the experimental conditions investigated. Consistent with the lack of ROS production, no change in cell viability was observed in Jurkat cells exposed to RF radiation for 24 h. Similar results were obtained when co-exposures were considered: combined exposures to RF radiation and FeSO4 did not increase ROS formation induced by the chemical treatment alone. In contrast, in cultures treated with FeSO4 as positive control, a dose-dependent increase in ROS formation was recorded, validating the sensitivity of the method employed. Bioelectromagnetics 30:525,535, 2009. © 2009 Wiley-Liss, Inc. [source] Evaluation of genotoxic effects in human leukocytes after in vitro exposure to 1950 MHz UMTS radiofrequency fieldBIOELECTROMAGNETICS, Issue 3 2008O. Zeni Abstract In the present study the third generation wireless technology of the Universal Mobile Telecommunication System (UMTS) signal was investigated for the induction of genotoxic effects in human leukocytes. Peripheral blood from six healthy donors was used and, for each donor, intermittent exposures (6 min RF on, 2 h RF off) at the frequency of 1950 MHz were conducted at a specific absorption rate of 2.2 W/kg. The exposures were performed in a transverse electro magnetic (TEM) cell hosted in an incubator under strictly controlled conditions of temperature and dosimetry. Following long duration intermittent RF exposures (from 24 to 68 h) in different stages of the cell cycle, micronucleus formation was evaluated by applying the cytokinesis block micronucleus assay, which also provides information on cell division kinetics. Primary DNA damage (strand breaks/alkali labile sites) was also investigated following 24 h of intermittent RF exposures, by applying the alkaline single cell gel electrophoresis (SCG)/comet assay. Positive controls were included by treating cell cultures with Mitomycin-C and methylmethanesulfonate for micronucleus and comet assays, respectively. The results obtained indicate that intermittent exposures of human lymphocytes in different stages of cell cycle do not induce either an increase in micronucleated cells, or change in cell cycle kinetics; moreover, 24 h intermittent exposures also fail to affect DNA structure of human leukocytes soon after the exposures, likely indicating that repairable DNA damage was not induced. Bioelectromagnetics 29:177,184, 2008. © 2007 Wiley-Liss, Inc. [source] Studies on microwaves in medicine and biology: From snails to humansBIOELECTROMAGNETICS, Issue 3 2004James C. Lin Abstract This d'Arsonval Medal acceptance presentation highlights several research themes selected from Dr. Lin's published works, focusing on the microwave portion of the nonionizing electromagnetic spectrum. The topics discussed include investigation of microwave effects on the spontaneous action potentials and membrane resistance of isolated snail neurons, effects on the permeability of blood brain barriers in rats, the phenomenon and interaction mechanism for the microwave auditory effect (the hearing of microwave pulses by animals and humans), the development of miniature catheter antennas for microwave interstitial hyperthermia treatment of cancer, the application of transcatheter microwave ablation for treatment of cardiac arrhythmias, and the use of noninvasive wireless technology for sensing of human vital signs and blood pressure pulse waves. The paper concludes with some observations on research and other endeavors in the interdisciplinary field of bioelectromagnetics. Bioelectromagnetics 25:146,159, 2004. © 2004 Wiley-Liss, Inc. [source] | |||||||||||||||||||