Sample records for ubiquitous link layer

  1. Ubiquitousness of link-density and link-pattern communities in real-world networks

    NASA Astrophysics Data System (ADS)

    Šubelj, L.; Bajec, M.

    2012-01-01

    Community structure appears to be an intrinsic property of many complex real-world networks. However, recent work shows that real-world networks reveal even more sophisticated modules than classical cohesive (link-density) communities. In particular, networks can also be naturally partitioned according to similar patterns of connectedness among the nodes, revealing link-pattern communities. We here propose a propagation based algorithm that can extract both link-density and link-pattern communities, without any prior knowledge of the true structure. The algorithm was first validated on different classes of synthetic benchmark networks with community structure, and also on random networks. We have further applied the algorithm to different social, information, technological and biological networks, where it indeed reveals meaningful (composites of) link-density and link-pattern communities. The results thus seem to imply that, similarly as link-density counterparts, link-pattern communities appear ubiquitous in nature and design.

  2. Ubiquitous human computing.

    PubMed

    Zittrain, Jonathan

    2008-10-28

    Ubiquitous computing means network connectivity everywhere, linking devices and systems as small as a drawing pin and as large as a worldwide product distribution chain. What could happen when people are so readily networked? This paper explores issues arising from two possible emerging models of ubiquitous human computing: fungible networked brainpower and collective personal vital sign monitoring.

  3. Inverted bulk-heterojunction solar cell with cross-linked hole-blocking layer

    PubMed Central

    Udum, Yasemin; Denk, Patrick; Adam, Getachew; Apaydin, Dogukan H.; Nevosad, Andreas; Teichert, Christian; S. White, Matthew.; S. Sariciftci, Niyazi.; Scharber, Markus C.

    2014-01-01

    We have developed a hole-blocking layer for bulk-heterojunction solar cells based on cross-linked polyethylenimine (PEI). We tested five different ether-based cross-linkers and found that all of them give comparable solar cell efficiencies. The initial idea that a cross-linked layer is more solvent resistant compared to a pristine PEI layer could not be confirmed. With and without cross-linking, the PEI layer sticks very well to the surface of the indium–tin–oxide electrode and cannot be removed by solvents used to process PEI or common organic semiconductors. The cross-linked PEI hole-blocking layer functions for multiple donor–acceptor blends. We found that using cross-linkers improves the reproducibility of the device fabrication process. PMID:24817837

  4. Linked Data: Forming Partnerships at the Data Layer

    NASA Astrophysics Data System (ADS)

    Shepherd, A.; Chandler, C. L.; Arko, R. A.; Jones, M. B.; Hitzler, P.; Janowicz, K.; Krisnadhi, A.; Schildhauer, M.; Fils, D.; Narock, T.; Groman, R. C.; O'Brien, M.; Patton, E. W.; Kinkade, D.; Rauch, S.

    2015-12-01

    The challenges presented by big data are straining data management software architectures of the past. For smaller existing data facilities, the technical refactoring of software layers become costly to scale across the big data landscape. In response to these challenges, data facilities will need partnerships with external entities for improved solutions to perform tasks such as data cataloging, discovery and reuse, and data integration and processing with provenance. At its surface, the concept of linked open data suggests an uncalculated altruism. Yet, in his concept of five star open data, Tim Berners-Lee explains the strategic costs and benefits of deploying linked open data from the perspective of its consumer and producer - a data partnership. The Biological and Chemical Oceanography Data Management Office (BCO-DMO) addresses some of the emerging needs of its research community by partnering with groups doing complementary work and linking their respective data layers using linked open data principles. Examples will show how these links, explicit manifestations of partnerships, reduce technical debt and provide a swift flexibility for future considerations.

  5. Community detection, link prediction, and layer interdependence in multilayer networks.

    PubMed

    De Bacco, Caterina; Power, Eleanor A; Larremore, Daniel B; Moore, Cristopher

    2017-04-01

    Complex systems are often characterized by distinct types of interactions between the same entities. These can be described as a multilayer network where each layer represents one type of interaction. These layers may be interdependent in complicated ways, revealing different kinds of structure in the network. In this work we present a generative model, and an efficient expectation-maximization algorithm, which allows us to perform inference tasks such as community detection and link prediction in this setting. Our model assumes overlapping communities that are common between the layers, while allowing these communities to affect each layer in a different way, including arbitrary mixtures of assortative, disassortative, or directed structure. It also gives us a mathematically principled way to define the interdependence between layers, by measuring how much information about one layer helps us predict links in another layer. In particular, this allows us to bundle layers together to compress redundant information and identify small groups of layers which suffice to predict the remaining layers accurately. We illustrate these findings by analyzing synthetic data and two real multilayer networks, one representing social support relationships among villagers in South India and the other representing shared genetic substring material between genes of the malaria parasite.

  6. Community detection, link prediction, and layer interdependence in multilayer networks

    NASA Astrophysics Data System (ADS)

    De Bacco, Caterina; Power, Eleanor A.; Larremore, Daniel B.; Moore, Cristopher

    2017-04-01

    Complex systems are often characterized by distinct types of interactions between the same entities. These can be described as a multilayer network where each layer represents one type of interaction. These layers may be interdependent in complicated ways, revealing different kinds of structure in the network. In this work we present a generative model, and an efficient expectation-maximization algorithm, which allows us to perform inference tasks such as community detection and link prediction in this setting. Our model assumes overlapping communities that are common between the layers, while allowing these communities to affect each layer in a different way, including arbitrary mixtures of assortative, disassortative, or directed structure. It also gives us a mathematically principled way to define the interdependence between layers, by measuring how much information about one layer helps us predict links in another layer. In particular, this allows us to bundle layers together to compress redundant information and identify small groups of layers which suffice to predict the remaining layers accurately. We illustrate these findings by analyzing synthetic data and two real multilayer networks, one representing social support relationships among villagers in South India and the other representing shared genetic substring material between genes of the malaria parasite.

  7. Effects of Link Annotations on Search Performance in Layered and Unlayered Hierarchically Organized Information Spaces.

    ERIC Educational Resources Information Center

    Fraser, Landon; Locatis, Craig

    2001-01-01

    Investigated the effects of link annotations on high school user search performance in Web hypertext environments having deep (layered) and shallow link structures. Results confirmed previous research that shallow link structures are better than deep (layered) link structures, and also showed that annotations had virtually no effect on search…

  8. Toward ubiquitous healthcare services with a novel efficient cloud platform.

    PubMed

    He, Chenguang; Fan, Xiaomao; Li, Ye

    2013-01-01

    Ubiquitous healthcare services are becoming more and more popular, especially under the urgent demand of the global aging issue. Cloud computing owns the pervasive and on-demand service-oriented natures, which can fit the characteristics of healthcare services very well. However, the abilities in dealing with multimodal, heterogeneous, and nonstationary physiological signals to provide persistent personalized services, meanwhile keeping high concurrent online analysis for public, are challenges to the general cloud. In this paper, we proposed a private cloud platform architecture which includes six layers according to the specific requirements. This platform utilizes message queue as a cloud engine, and each layer thereby achieves relative independence by this loosely coupled means of communications with publish/subscribe mechanism. Furthermore, a plug-in algorithm framework is also presented, and massive semistructure or unstructured medical data are accessed adaptively by this cloud architecture. As the testing results showing, this proposed cloud platform, with robust, stable, and efficient features, can satisfy high concurrent requests from ubiquitous healthcare services.

  9. Nanomechanics of layer-by-layer polyelectrolyte complexes: a manifestation of ionic cross-links and fixed charges.

    PubMed

    Han, Biao; Chery, Daphney R; Yin, Jie; Lu, X Lucas; Lee, Daeyeon; Han, Lin

    2016-01-28

    This study investigates the roles of two distinct features of ionically cross-linked polyelectrolyte networks - ionic cross-links and fixed charges - in determining their nanomechanical properties. The layer-by-layer assembled poly(allylamine hydrochloride)/poly(acrylic acid) (PAH/PAA) network is used as the model material. The densities of ionic cross-links and fixed charges are modulated through solution pH and ionic strength (IS), and the swelling ratio, elastic and viscoelastic properties are quantified via an array of atomic force microscopy (AFM)-based nanomechanical tools. The roles of ionic cross-links are underscored by the distinctive elastic and viscoelastic nanomechanical characters observed here. First, as ionic cross-links are highly sensitive to solution conditions, the instantaneous modulus, E0, exhibits orders-of-magnitude changes upon pH- and IS-governed swelling, distinctive from the rubber elasticity prediction based on permanent covalent cross-links. Second, ionic cross-links can break and self-re-form, and this mechanism dominates force relaxation of PAH/PAA under a constant indentation depth. In most states, the degree of relaxation is >90%, independent of ionic cross-link density. The importance of fixed charges is highlighted by the unexpectedly more elastic nature of the network despite low ionic cross-link density at pH 2.0, IS 0.01 M. Here, the complex is a net charged, loosely cross-linked, where the degree of relaxation is attenuated to ≈50% due to increased elastic contribution arising from fixed charge-induced Donnan osmotic pressure. In addition, this study develops a new method for quantifying the thickness of highly swollen polymer hydrogel films. It also underscores important technical considerations when performing nanomechanical tests on highly rate-dependent polymer hydrogel networks. These results provide new insights into the nanomechanical characters of ionic polyelectrolyte complexes, and lay the ground for further

  10. Link and Network Layers Design for Ultra-High-Speed Terahertz-Band Communications Networks

    DTIC Science & Technology

    2017-01-01

    throughput, and identify the optimal parameter values for their design (Sec. 6.2.3). Moreover, we validate and test the scheme with experimental data obtained...LINK AND NETWORK LAYERS DESIGN FOR ULTRA-HIGH- SPEED TERAHERTZ-BAND COMMUNICATIONS NETWORKS STATE UNIVERSITY OF NEW YORK (SUNY) AT BUFFALO JANUARY...TYPE FINAL TECHNICAL REPORT 3. DATES COVERED (From - To) FEB 2015 – SEP 2016 4. TITLE AND SUBTITLE LINK AND NETWORK LAYERS DESIGN FOR ULTRA-HIGH

  11. Ubiquitous Versus One-to-One

    ERIC Educational Resources Information Center

    McAnear, Anita

    2006-01-01

    When we planned the editorial calendar with the topic ubiquitous computing, we were thinking of ubiquitous computing as the one-to-one ratio of computers to students and teachers and 24/7 access to electronic resources. At the time, we were aware that ubiquitous computing in the computer science field had more to do with wearable computers. Our…

  12. Research and implementation of SATA protocol link layer based on FPGA

    NASA Astrophysics Data System (ADS)

    Liu, Wen-long; Liu, Xue-bin; Qiang, Si-miao; Yan, Peng; Wen, Zhi-gang; Kong, Liang; Liu, Yong-zheng

    2018-02-01

    In order to solve the problem high-performance real-time, high-speed the image data storage generated by the detector. In this thesis, it choose an suitable portable image storage hard disk of SATA interface, it is relative to the existing storage media. It has a large capacity, high transfer rate, inexpensive, power-down data which is not lost, and many other advantages. This paper focuses on the link layer of the protocol, analysis the implementation process of SATA2.0 protocol, and build state machines. Then analyzes the characteristics resources of Kintex-7 FPGA family, builds state machines according to the agreement, write Verilog implement link layer modules, and run the simulation test. Finally, the test is on the Kintex-7 development board platform. It meets the requirements SATA2.0 protocol basically.

  13. Effectiveness evaluation of double-layered satellite network with laser and microwave hybrid links based on fuzzy analytic hierarchy process

    NASA Astrophysics Data System (ADS)

    Zhang, Wei; Rao, Qiaomeng

    2018-01-01

    In order to solve the problem of high speed, large capacity and limited spectrum resources of satellite communication network, a double-layered satellite network with global seamless coverage based on laser and microwave hybrid links is proposed in this paper. By analyzing the characteristics of the double-layered satellite network with laser and microwave hybrid links, an effectiveness evaluation index system for the network is established. And then, the fuzzy analytic hierarchy process, which combines the analytic hierarchy process and the fuzzy comprehensive evaluation theory, is used to evaluate the effectiveness of the double-layered satellite network with laser and microwave hybrid links. Furthermore, the evaluation result of the proposed hybrid link network is obtained by simulation. The effectiveness evaluation process of the proposed double-layered satellite network with laser and microwave hybrid links can help to optimize the design of hybrid link double-layered satellite network and improve the operating efficiency of the satellite system.

  14. Observations on sustainable and ubiquitous healthcare informatics from Florence Nightingale.

    PubMed

    Betts, Helen J; Wright, Graham

    2009-01-01

    As nurses around the world prepare to celebrate the centenary of the death of Florence Nightingale in 2010 this paper reviews her work on using information, especially statistics, to analyze and manage patient care and links that to current developments in informatics. It then examines assistive technologies and how they may impact on nursing practice in the future and links these developments to the writings of Florence Nightingale. The paper concludes by suggesting that in progressing towards sustainable and ubiquitous healthcare informatics we need to study history in order to learn from the lessons of Florence Nightingale and other healthcare pioneers.

  15. Learning with Ubiquitous Computing

    ERIC Educational Resources Information Center

    Rosenheck, Louisa

    2008-01-01

    If ubiquitous computing becomes a reality and is widely adopted, it will inevitably have an impact on education. This article reviews the background of ubiquitous computing and current research projects done involving educational "ubicomp." Finally it explores how ubicomp may and may not change education in both formal and informal settings and…

  16. Programmable ubiquitous telerobotic devices

    NASA Astrophysics Data System (ADS)

    Doherty, Michael; Greene, Matthew; Keaton, David; Och, Christian; Seidl, Matthew L.; Waite, William; Zorn, Benjamin G.

    1997-12-01

    We are investigating a field of research that we call ubiquitous telepresence, which involves the design and implementation of low-cost robotic devices that can be programmed and operated from anywhere on the Internet. These devices, which we call ubots, can be used for academic purposes (e.g., a biologist could remote conduct a population survey), commercial purposes (e.g., a house could be shown remotely by a real-estate agent), and for recreation and education (e.g., someone could tour a museum remotely). We anticipate that such devices will become increasingly common due to recent changes in hardware and software technology. In particular, current hardware technology enables such devices to be constructed very cheaply (less than $500), and current software and network technology allows highly portable code to be written and downloaded across the Internet. In this paper, we present our prototype system architecture, and the ubot implementation we have constructed based on it. The hardware technology we use is the handy board, a 6811-based controller board with digital and analog inputs and outputs. Our software includes a network layer based on TCP/IP and software layers written in Java. Our software enables users across the Internet to program the behavior of the vehicle and to receive image feedback from a camera mounted on it.

  17. A Collaborative Model for Ubiquitous Learning Environments

    ERIC Educational Resources Information Center

    Barbosa, Jorge; Barbosa, Debora; Rabello, Solon

    2016-01-01

    Use of mobile devices and widespread adoption of wireless networks have enabled the emergence of Ubiquitous Computing. Application of this technology to improving education strategies gave rise to Ubiquitous e-Learning, also known as Ubiquitous Learning. There are several approaches to organizing ubiquitous learning environments, but most of them…

  18. Lightweight Biometric Sensing for Walker Classification Using Narrowband RF Links

    PubMed Central

    Liang, Zhuo-qian

    2017-01-01

    This article proposes a lightweight biometric sensing system using ubiquitous narrowband radio frequency (RF) links for path-dependent walker classification. The fluctuated received signal strength (RSS) sequence generated by human motion is used for feature representation. To capture the most discriminative characteristics of individuals, a three-layer RF sensing network is organized for building multiple sampling links at the most common heights of upper limbs, thighs, and lower legs. The optimal parameters of sensing configuration, such as the height of link location and number of fused links, are investigated to improve sensory data distinctions among subjects, and the experimental results suggest that the synergistic sensing by using multiple links can contribute a better performance. This is the new consideration of using RF links in building a biometric sensing system. In addition, two types of classification methods involving vector quantization (VQ) and hidden Markov models (HMMs) are developed and compared for closed-set walker recognition and verification. Experimental studies in indoor line-of-sight (LOS) and non-line-of-sight (NLOS) scenarios are conducted to validate the proposed method. PMID:29206188

  19. Lightweight Biometric Sensing for Walker Classification Using Narrowband RF Links.

    PubMed

    Liu, Tong; Liang, Zhuo-Qian

    2017-12-05

    This article proposes a lightweight biometric sensing system using ubiquitous narrowband radio frequency (RF) links for path-dependent walker classification. The fluctuated received signal strength (RSS) sequence generated by human motion is used for feature representation. To capture the most discriminative characteristics of individuals, a three-layer RF sensing network is organized for building multiple sampling links at the most common heights of upper limbs, thighs, and lower legs. The optimal parameters of sensing configuration, such as the height of link location and number of fused links, are investigated to improve sensory data distinctions among subjects, and the experimental results suggest that the synergistic sensing by using multiple links can contribute a better performance. This is the new consideration of using RF links in building a biometric sensing system. In addition, two types of classification methods involving vector quantization (VQ) and hidden Markov models (HMMs) are developed and compared for closed-set walker recognition and verification. Experimental studies in indoor line-of-sight (LOS) and non-line-of-sight (NLOS) scenarios are conducted to validate the proposed method.

  20. A Dynamic Ubiquitous Learning Resource Model with Context and Its Effects on Ubiquitous Learning

    ERIC Educational Resources Information Center

    Chen, Min; Yu, Sheng Quan; Chiang, Feng Kuang

    2017-01-01

    Most ubiquitous learning researchers use resource recommendation and retrieving based on context to provide contextualized learning resources, but it is the kind of one-way context matching. Learners always obtain fixed digital learning resources, which present all learning contents in any context. This study proposed a dynamic ubiquitous learning…

  1. Studies of free-space optical links through simulated boundary layer and long-path turbulence

    NASA Astrophysics Data System (ADS)

    Wasiczko, Linda; Smolyaninov, Igor I.; Milner, Stuart D.; Davis, Christopher C.

    2004-02-01

    There is recent interest from the US Department of Defense in free space optical communication networks involving aircraft flying at various altitudes. The optical links between these aircraft may be as long as 100km, and involve communication between network nodes that are moving at sub-sonic speeds. An unresolved issue for links of this kind between pairs of aircraft is the effect of boundary layer turbulence near each aircraft, as well as along the atmospheric path between them. The deployment of optical wireless links in several different scenarios will be described. These include links near to the ground for which the turbulence parameter Cn2 varies along the path between transmitter (TX) and receiver (RX), high altitude links between aircraft, and ground to aircraft links. The last two of these may involve boundary layer turbulence near the aircraft node where the turbulence is localized either at the TX or at the RX. Some of the theoretical approaches to examining these situations will be described, as well as an ongoing program of research to examine these situations experimentally. Ways to mitigate the effects of node motion, and scintillation at the RX will be discussed, including the use of non-imaging concentrators at the RX.

  2. Technologies for Achieving Field Ubiquitous Computing

    NASA Astrophysics Data System (ADS)

    Nagashima, Akira

    Although the term “ubiquitous” may sound like jargon used in information appliances, ubiquitous computing is an emerging concept in industrial automation. This paper presents the author's visions of field ubiquitous computing, which is based on the novel Internet Protocol IPv6. IPv6-based instrumentation will realize the next generation manufacturing excellence. This paper focuses on the following five key issues: 1. IPv6 standardization; 2. IPv6 interfaces embedded in field devices; 3. Compatibility with FOUNDATION fieldbus; 4. Network securities for field applications; and 5. Wireless technologies to complement IP instrumentation. Furthermore, the principles of digital plant operations and ubiquitous production to support the above key technologies to achieve field ubiquitous systems are discussed.

  3. Developing a Standard Method for Link-Layer Security of CCSDS Space Communications

    NASA Technical Reports Server (NTRS)

    Biggerstaff, Craig

    2009-01-01

    Communications security for space systems has been a specialized field generally far removed from considerations of mission interoperability and cross-support in fact, these considerations often have been viewed as intrinsically opposed to security objectives. The space communications protocols defined by the Consultative Committee for Space Data Systems (CCSDS) have a twenty-five year history of successful use in over 400 missions. While the CCSDS Telemetry, Telecommand, and Advancing Orbiting Systems protocols for use at OSI Layer 2 are operationally mature, there has been no direct support within these protocols for communications security techniques. Link-layer communications security has been successfully implemented in the past using mission-unique methods, but never before with an objective of facilitating cross-support and interoperability. This paper discusses the design of a standard method for cryptographic authentication, encryption, and replay protection at the data link layer that can be integrated into existing CCSDS protocols without disruption to legacy communications services. Integrating cryptographic operations into existing data structures and processing sequences requires a careful assessment of the potential impediments within spacecraft, ground stations, and operations centers. The objective of this work is to provide a sound method for cryptographic encapsulation of frame data that also facilitates Layer 2 virtual channel switching, such that a mission may procure data transport services as needed without involving third parties in the cryptographic processing, or split independent data streams for separate cryptographic processing.

  4. Ubiquitous computing in the military environment

    NASA Astrophysics Data System (ADS)

    Scholtz, Jean

    2001-08-01

    Increasingly people work and live on the move. To support this mobile lifestyle, especially as our work becomes more intensely information-based, companies are producing various portable and embedded information devices. The late Mark Weiser coined the term, 'ubiquitous computing' to describe an environment where computers have disappeared and are integrated into physical objects. Much industry research today is concerned with ubiquitous computing in the work and home environments. A ubiquitous computing environment would facilitate mobility by allowing information users to easily access and use information anytime, anywhere. As war fighters are inherently mobile, the question is what effect a ubiquitous computing environment would have on current military operations and doctrine. And, if ubiquitous computing is viewed as beneficial for the military, what research would be necessary to achieve a military ubiquitous computing environment? What is a vision for the use of mobile information access in a battle space? Are there different requirements for civilian and military users of this technology? What are those differences? Are there opportunities for research that will support both worlds? What type of research has been supported by the military and what areas need to be investigated? Although we don't yet have all the answers to these questions, this paper discusses the issues and presents the work we are doing to address these issues.

  5. The Future of Ubiquitous Elearning

    ERIC Educational Resources Information Center

    Arndt, Timothy

    2014-01-01

    Post-secondary students are increasingly receiving instruction by eLearning. Many or these are part-time students or are working while taking classes. In such circumstances, students may find themselves short of time to study. One mechanism that can be exploited to make the best use of available time is ubiquitous eLearning. Ubiquitous eLearning…

  6. Criteria for Evaluating Alternative Network and Link Layer Protocols for the NASA Constellation Program Communication Architecture

    NASA Technical Reports Server (NTRS)

    Benbenek, Daniel; Soloff, Jason; Lieb, Erica

    2010-01-01

    Selecting a communications and network architecture for future manned space flight requires an evaluation of the varying goals and objectives of the program, development of communications and network architecture evaluation criteria, and assessment of critical architecture trades. This paper uses Cx Program proposed exploration activities as a guideline; lunar sortie, outpost, Mars, and flexible path options are described. A set of proposed communications network architecture criteria are proposed and described. They include: interoperability, security, reliability, and ease of automating topology changes. Finally a key set of architecture options are traded including (1) multiplexing data at a common network layer vs. at the data link layer, (2) implementing multiple network layers vs. a single network layer, and (3) the use of a particular network layer protocol, primarily IPv6 vs. Delay Tolerant Networking (DTN). In summary, the protocol options are evaluated against the proposed exploration activities and their relative performance with respect to the criteria are assessed. An architectural approach which includes (a) the capability of multiplexing at both the network layer and the data link layer and (b) a single network layer for operations at each program phase, as these solutions are best suited to respond to the widest array of program needs and meet each of the evaluation criteria.

  7. UBIQUITOUS SOLAR ERUPTIONS DRIVEN BY MAGNETIZED VORTEX TUBES

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kitiashvili, I. N.; Kosovichev, A. G.; Lele, S. K.

    2013-06-10

    The solar surface is covered by high-speed jets transporting mass and energy into the solar corona and feeding the solar wind. The most prominent of these jets have been known as spicules. However, the mechanism initiating these eruption events is still unknown. Using realistic numerical simulations we find that small-scale eruptions are produced by ubiquitous magnetized vortex tubes generated by the Sun's turbulent convection in subsurface layers. The swirling vortex tubes (resembling tornadoes) penetrate into the solar atmosphere, capture and stretch background magnetic field, and push the surrounding material up, generating shocks. Our simulations reveal complicated high-speed flow patterns andmore » thermodynamic and magnetic structure in the erupting vortex tubes. The main new results are: (1) the eruptions are initiated in the subsurface layers and are driven by high-pressure gradients in the subphotosphere and photosphere and by the Lorentz force in the higher atmosphere layers; (2) the fluctuations in the vortex tubes penetrating into the chromosphere are quasi-periodic with a characteristic period of 2-5 minutes; and (3) the eruptions are highly non-uniform: the flows are predominantly downward in the vortex tube cores and upward in their surroundings; the plasma density and temperature vary significantly across the eruptions.« less

  8. Dashboard for Analyzing Ubiquitous Learning Log

    ERIC Educational Resources Information Center

    Lkhagvasuren, Erdenesaikhan; Matsuura, Kenji; Mouri, Kousuke; Ogata, Hiroaki

    2016-01-01

    Mobile and ubiquitous technologies have been applied to a wide range of learning fields such as science, social science, history and language learning. Many researchers have been investigating the development of ubiquitous learning environments; nevertheless, to date, there have not been enough research works related to the reflection, analysis…

  9. Frequent statistics of link-layer bit stream data based on AC-IM algorithm

    NASA Astrophysics Data System (ADS)

    Cao, Chenghong; Lei, Yingke; Xu, Yiming

    2017-08-01

    At present, there are many relevant researches on data processing using classical pattern matching and its improved algorithm, but few researches on statistical data of link-layer bit stream. This paper adopts a frequent statistical method of link-layer bit stream data based on AC-IM algorithm for classical multi-pattern matching algorithms such as AC algorithm has high computational complexity, low efficiency and it cannot be applied to binary bit stream data. The method's maximum jump distance of the mode tree is length of the shortest mode string plus 3 in case of no missing? In this paper, theoretical analysis is made on the principle of algorithm construction firstly, and then the experimental results show that the algorithm can adapt to the binary bit stream data environment and extract the frequent sequence more accurately, the effect is obvious. Meanwhile, comparing with the classical AC algorithm and other improved algorithms, AC-IM algorithm has a greater maximum jump distance and less time-consuming.

  10. Ubiquitous geospatial concept in evolution of the macro and micro spatial planning

    NASA Astrophysics Data System (ADS)

    Sabri, S.; Ludin, A. N. M.; Majid, M. R.

    2014-02-01

    There are many examples of GIS application in planning such as urban land-use planning, cultural heritage conservation, coastal zone management, and the design of structure plans for sustainable economic development. All these applications are dealing with systems in which natural and human factors are interconnected. But an issue that should be addressed is to what extent the current information technology is able to connect all these parts together? Contemporary improvement in information technology made the computer so imbedded in our everyday practices that we use it without having to think about it. Thus, computing is becoming truly ubiquitous and is available anywhere anytime. Advances in the internet facilities and devices, such as high speed wireless networks, mobile middleware, and smart technologies, has pushed the concept of ubiquitous computing to the forefront of GIS research and development. There are developments in this regards, these are such as GeoWeb 2.0, voluntarily geographic Information (VGI), and Mashups, whereby the application of cloud computing was possible in visualizing urban air pollution and emergency responses to ensure the safety and security. These advancements therefore, have changed the conventional facet of macro and micro spatial planning. Every possible information system such as residential, medical, business, environmental, governmental, and the like can be linked through ubiquitous computing technologies and acts as a virtually one system which works for society. However, the journey to achieve a true ubiquitous GIS is not without challenges. Despite the current potentials there are many issues and obstacles need to be addressed before GIS can to be truly ubiquitous in planning context. Perhaps four criteria as explained by Goodchild et al (1997) can be applied to ubiquitous GIS in planning very well: the system must be distributed (data storage, processing and user interaction can occur at locations that are potentially

  11. SignaLink 2 - a signaling pathway resource with multi-layered regulatory networks.

    PubMed

    Fazekas, Dávid; Koltai, Mihály; Türei, Dénes; Módos, Dezső; Pálfy, Máté; Dúl, Zoltán; Zsákai, Lilian; Szalay-Bekő, Máté; Lenti, Katalin; Farkas, Illés J; Vellai, Tibor; Csermely, Péter; Korcsmáros, Tamás

    2013-01-18

    Signaling networks in eukaryotes are made up of upstream and downstream subnetworks. The upstream subnetwork contains the intertwined network of signaling pathways, while the downstream regulatory part contains transcription factors and their binding sites on the DNA as well as microRNAs and their mRNA targets. Currently, most signaling and regulatory databases contain only a subsection of this network, making comprehensive analyses highly time-consuming and dependent on specific data handling expertise. The need for detailed mapping of signaling systems is also supported by the fact that several drug development failures were caused by undiscovered cross-talk or regulatory effects of drug targets. We previously created a uniformly curated signaling pathway resource, SignaLink, to facilitate the analysis of pathway cross-talks. Here, we present SignaLink 2, which significantly extends the coverage and applications of its predecessor. We developed a novel concept to integrate and utilize different subsections (i.e., layers) of the signaling network. The multi-layered (onion-like) database structure is made up of signaling pathways, their pathway regulators (e.g., scaffold and endocytotic proteins) and modifier enzymes (e.g., phosphatases, ubiquitin ligases), as well as transcriptional and post-transcriptional regulators of all of these components. The user-friendly website allows the interactive exploration of how each signaling protein is regulated. The customizable download page enables the analysis of any user-specified part of the signaling network. Compared to other signaling resources, distinctive features of SignaLink 2 are the following: 1) it involves experimental data not only from humans but from two invertebrate model organisms, C. elegans and D. melanogaster; 2) combines manual curation with large-scale datasets; 3) provides confidence scores for each interaction; 4) operates a customizable download page with multiple file formats (e.g., Bio

  12. Non-Orthogonal Multiple Access for Ubiquitous Wireless Sensor Networks.

    PubMed

    Anwar, Asim; Seet, Boon-Chong; Ding, Zhiguo

    2018-02-08

    Ubiquitous wireless sensor networks (UWSNs) have become a critical technology for enabling smart cities and other ubiquitous monitoring applications. Their deployment, however, can be seriously hampered by the spectrum available to the sheer number of sensors for communication. To support the communication needs of UWSNs without requiring more spectrum resources, the power-domain non-orthogonal multiple access (NOMA) technique originally proposed for 5th Generation (5G) cellular networks is investigated for UWSNs for the first time in this paper. However, unlike 5G networks that operate in the licensed spectrum, UWSNs mostly operate in unlicensed spectrum where sensors also experience cross-technology interferences from other devices sharing the same spectrum. In this paper, we model the interferences from various sources at the sensors using stochastic geometry framework. To evaluate the performance, we derive a theorem and present new closed form expression for the outage probability of the sensors in a downlink scenario under interference limited environment. In addition, diversity analysis for the ordered NOMA users is performed. Based on the derived outage probability, we evaluate the average link throughput and energy consumption efficiency of NOMA against conventional orthogonal multiple access (OMA) technique in UWSNs. Further, the required computational complexity for the NOMA users is presented.

  13. Privacy-related context information for ubiquitous health.

    PubMed

    Seppälä, Antto; Nykänen, Pirkko; Ruotsalainen, Pekka

    2014-03-11

    Ubiquitous health has been defined as a dynamic network of interconnected systems. A system is composed of one or more information systems, their stakeholders, and the environment. These systems offer health services to individuals and thus implement ubiquitous computing. Privacy is the key challenge for ubiquitous health because of autonomous processing, rich contextual metadata, lack of predefined trust among participants, and the business objectives. Additionally, regulations and policies of stakeholders may be unknown to the individual. Context-sensitive privacy policies are needed to regulate information processing. Our goal was to analyze privacy-related context information and to define the corresponding components and their properties that support privacy management in ubiquitous health. These properties should describe the privacy issues of information processing. With components and their properties, individuals can define context-aware privacy policies and set their privacy preferences that can change in different information-processing situations. Scenarios and user stories are used to analyze typical activities in ubiquitous health to identify main actors, goals, tasks, and stakeholders. Context arises from an activity and, therefore, we can determine different situations, services, and systems to identify properties for privacy-related context information in information-processing situations. Privacy-related context information components are situation, environment, individual, information technology system, service, and stakeholder. Combining our analyses and previously identified characteristics of ubiquitous health, more detailed properties for the components are defined. Properties define explicitly what context information for different components is needed to create context-aware privacy policies that can control, limit, and constrain information processing. With properties, we can define, for example, how data can be processed or how components

  14. A wearable context aware system for ubiquitous healthcare.

    PubMed

    Kang, Dong-Oh; Lee, Hyung-Jik; Ko, Eun-Jung; Kang, Kyuchang; Lee, Jeunwoo

    2006-01-01

    Recent developments of information technologies are leading the advent of the era of ubiquitous healthcare, which means healthcare services at any time and at any places. The ubiquitous healthcare service needs a wearable system for more continual measurement of biological signals of a user, which gives information of the user from wearable sensors. In this paper, we propose a wearable context aware system for ubiquitous healthcare, and its systematic design process of a ubiquitous healthcare service. Some wearable sensor systems are introduced with Zigbee communication. We develop a context aware framework to send information from wearable sensors to healthcare service entities as a middleware to solve the interoperability problem between sensor makers and healthcare service providers. And, we propose a systematic process of design of ubiquitous healthcare services with the context aware framework. In order to show the feasibility of the proposed system, some application examples are given, which are applied to remote monitoring, and a self check service.

  15. Ubiquitous Sensor Networking for Development (USN4D): an application to pollution monitoring.

    PubMed

    Bagula, Antoine; Zennaro, Marco; Inggs, Gordon; Scott, Simon; Gascon, David

    2012-01-01

    This paper presents a new Ubiquitous Sensor Network (USN) Architecture to be used in developing countries and reveals its usefulness by highlighting some of its key features. In complement to a previous ITU proposal, our architecture referred to as "Ubiquitous Sensor Network for Development (USN4D)" integrates in its layers features such as opportunistic data dissemination, long distance deployment and localisation of information to meet the requirements of the developing world. Besides describing some of the most important requirements for the sensor equipment to be used in a USN4D setting, we present the main features and experiments conducted using the "WaspNet" as one of the wireless sensor deployment platforms that meets these requirements. Furthermore, building upon "WaspNet" platform, we present an application to Air pollution Monitoring in the city of Cape Town, in South Africa as one of the first steps towards building community wireless sensor networks (CSN) in the developing world using off-the-shelf sensor equipment.

  16. Integrating Collaborative and Decentralized Models to Support Ubiquitous Learning

    ERIC Educational Resources Information Center

    Barbosa, Jorge Luis Victória; Barbosa, Débora Nice Ferrari; Rigo, Sandro José; de Oliveira, Jezer Machado; Rabello, Solon Andrade, Jr.

    2014-01-01

    The application of ubiquitous technologies in the improvement of education strategies is called Ubiquitous Learning. This article proposes the integration between two models dedicated to support ubiquitous learning environments, called Global and CoolEdu. CoolEdu is a generic collaboration model for decentralized environments. Global is an…

  17. The Construction of an Ontology-Based Ubiquitous Learning Grid

    ERIC Educational Resources Information Center

    Liao, Ching-Jung; Chou, Chien-Chih; Yang, Jin-Tan David

    2009-01-01

    The purpose of this study is to incorporate adaptive ontology into ubiquitous learning grid to achieve seamless learning environment. Ubiquitous learning grid uses ubiquitous computing environment to infer and determine the most adaptive learning contents and procedures in anytime, any place and with any device. To achieve the goal, an…

  18. Privacy-Related Context Information for Ubiquitous Health

    PubMed Central

    Nykänen, Pirkko; Ruotsalainen, Pekka

    2014-01-01

    Background Ubiquitous health has been defined as a dynamic network of interconnected systems. A system is composed of one or more information systems, their stakeholders, and the environment. These systems offer health services to individuals and thus implement ubiquitous computing. Privacy is the key challenge for ubiquitous health because of autonomous processing, rich contextual metadata, lack of predefined trust among participants, and the business objectives. Additionally, regulations and policies of stakeholders may be unknown to the individual. Context-sensitive privacy policies are needed to regulate information processing. Objective Our goal was to analyze privacy-related context information and to define the corresponding components and their properties that support privacy management in ubiquitous health. These properties should describe the privacy issues of information processing. With components and their properties, individuals can define context-aware privacy policies and set their privacy preferences that can change in different information-processing situations. Methods Scenarios and user stories are used to analyze typical activities in ubiquitous health to identify main actors, goals, tasks, and stakeholders. Context arises from an activity and, therefore, we can determine different situations, services, and systems to identify properties for privacy-related context information in information-processing situations. Results Privacy-related context information components are situation, environment, individual, information technology system, service, and stakeholder. Combining our analyses and previously identified characteristics of ubiquitous health, more detailed properties for the components are defined. Properties define explicitly what context information for different components is needed to create context-aware privacy policies that can control, limit, and constrain information processing. With properties, we can define, for example, how

  19. Ubiquitous Graphene Electronics on Scotch Tape

    PubMed Central

    Chung, Yoonyoung; Ho Kim, Hyun; Lee, Sangryun; Lee, Eunho; Won Kim, Seong; Ryu, Seunghwa; Cho, Kilwon

    2015-01-01

    We report a novel concept of graphene transistors on Scotch tape for use in ubiquitous electronic systems. Unlike common plastic substrates such as polyimide and polyethylene terephthalate, the Scotch tape substrate is easily attached onto various objects such as banknotes, curved surfaces, and human skin, which implies potential applications wherein electronics can be placed in any desired position. Furthermore, the soft Scotch tape serves as an attractive substrate for flexible/foldable electronics that can be significantly bent, or even crumpled. We found that the adhesive layer of the tape with a relatively low shear modulus relaxes the strain when subjected to bending. The capacitance of the gate dielectric made of oxidized aluminum oxide was 1.5 μF cm−2, so that a supply voltage of only 2.5 V was sufficient to operate the devices. As-fabricated graphene transistors on Scotch tape exhibited high electron mobility of 1326 (±155) cm2 V−1 s−1; the transistors still showed high mobility of 1254 (±478) cm2 V−1 s−1 even after they were crumpled. PMID:26220874

  20. CILT2000: Ubiquitous Computing--Spanning the Digital Divide.

    ERIC Educational Resources Information Center

    Tinker, Robert; Vahey, Philip

    2002-01-01

    Discusses the role of ubiquitous and handheld computers in education. Summarizes the contributions of the Center for Innovative Learning Technologies (CILT) and describes the ubiquitous computing sessions at the CILT2000 Conference. (Author/YDS)

  1. Ubiquitous equatorial accretion disc winds in black hole soft states

    NASA Astrophysics Data System (ADS)

    Ponti, G.; Fender, R. P.; Begelman, M. C.; Dunn, R. J. H.; Neilsen, J.; Coriat, M.

    2012-05-01

    High-resolution spectra of Galactic black holes (GBHs) reveal the presence of highly ionized absorbers. In one GBH, accreting close to the Eddington limit for more than a decade, a powerful accretion disc wind is observed to be present in softer X-ray states and it has been suggested that it can carry away enough mass and energy to quench the radio jet. Here we report that these winds, which may have mass outflow rates of the order of the inner accretion rate or higher, are a ubiquitous component of the jet-free soft states of all GBHs. We furthermore demonstrate that these winds have an equatorial geometry with opening angles of few tens of degrees, and so are only observed in sources in which the disc is inclined at a large angle to the line of sight. The decrease in Fe XXV/Fe XXVI line ratio with Compton temperature, observed in the soft state, suggests a link between higher wind ionization and harder spectral shapes. Although the physical interaction between the wind, accretion flow and jet is still not fully understood, the mass flux and power of these winds and their presence ubiquitously during the soft X-ray states suggest they are fundamental components of the accretion phenomenon.

  2. Ubiquitous Sensor Networking for Development (USN4D): An Application to Pollution Monitoring

    PubMed Central

    Bagula, Antoine; Zennaro, Marco; Inggs, Gordon; Scott, Simon; Gascon, David

    2012-01-01

    This paper presents a new Ubiquitous Sensor Network (USN) Architecture to be used in developing countries and reveals its usefulness by highlighting some of its key features. In complement to a previous ITU proposal, our architecture referred to as “Ubiquitous Sensor Network for Development (USN4D)” integrates in its layers features such as opportunistic data dissemination, long distance deployment and localisation of information to meet the requirements of the developing world. Besides describing some of the most important requirements for the sensor equipment to be used in a USN4D setting, we present the main features and experiments conducted using the “WaspNet” as one of the wireless sensor deployment platforms that meets these requirements. Furthermore, building upon “WaspNet” platform, we present an application to Air pollution Monitoring in the city of Cape Town, in South Africa as one of the first steps towards building community wireless sensor networks (CSN) in the developing world using off-the-shelf sensor equipment. PMID:22368476

  3. Ubiquitous Learning Environments in Higher Education: A Scoping Literature Review

    ERIC Educational Resources Information Center

    Virtanen, Mari Aulikki; Haavisto, Elina; Liikanen, Eeva; Kääriäinen, Maria

    2018-01-01

    Ubiquitous learning and the use of ubiquitous learning environments heralds a new era in higher education. Ubiquitous learning environments enhance context-aware and seamless learning experiences available from any location at any time. They support smooth interaction between authentic and digital learning resources and provide personalized…

  4. New functionalities in abundant element oxides: ubiquitous element strategy

    PubMed Central

    Hosono, Hideo; Hayashi, Katsuro; Kamiya, Toshio; Atou, Toshiyuki; Susaki, Tomofumi

    2011-01-01

    While most ceramics are composed of ubiquitous elements (the ten most abundant elements within the Earth's crust), many advanced materials are based on rare elements. A ‘rare-element crisis’ is approaching owing to the imbalance between the limited supply of rare elements and the increasing demand. Therefore, we propose a ‘ubiquitous element strategy’ for materials research, which aims to apply abundant elements in a variety of innovative applications. Creation of innovative oxide materials and devices based on conventional ceramics is one specific challenge. This review describes the concept of ubiquitous element strategy and gives some highlights of our recent research on the synthesis of electronic, thermionic and structural materials using ubiquitous elements. PMID:27877391

  5. Inter-layer synchronization in non-identical multi-layer networks

    NASA Astrophysics Data System (ADS)

    Leyva, I.; Sevilla-Escoboza, R.; Sendiña-Nadal, I.; Gutiérrez, R.; Buldú, J. M.; Boccaletti, S.

    2017-04-01

    Inter-layer synchronization is a dynamical process occurring in multi-layer networks composed of identical nodes. This process emerges when all layers are synchronized, while nodes in each layer do not necessarily evolve in unison. So far, the study of such inter-layer synchronization has been restricted to the case in which all layers have an identical connectivity structure. When layers are not identical, the inter-layer synchronous state is no longer a stable solution of the system. Nevertheless, when layers differ in just a few links, an approximate treatment is still feasible, and allows one to gather information on whether and how the system may wander around an inter-layer synchronous configuration. We report the details of an approximate analytical treatment for a two-layer multiplex, which results in the introduction of an extra inertial term accounting for structural differences. Numerical validation of the predictions highlights the usefulness of our approach, especially for small or moderate topological differences in the intra-layer coupling. Moreover, we identify a non-trivial relationship connecting the betweenness centrality of the missing links and the intra-layer coupling strength. Finally, by the use of multiplexed layers of electronic circuits, we study the inter-layer synchronization as a function of the removed links.

  6. Ubiquitous information for ubiquitous computing: expressing clinical data sets with openEHR archetypes.

    PubMed

    Garde, Sebastian; Hovenga, Evelyn; Buck, Jasmin; Knaup, Petra

    2006-01-01

    Ubiquitous computing requires ubiquitous access to information and knowledge. With the release of openEHR Version 1.0 there is a common model available to solve some of the problems related to accessing information and knowledge by improving semantic interoperability between clinical systems. Considerable work has been undertaken by various bodies to standardise Clinical Data Sets. Notwithstanding their value, several problems remain unsolved with Clinical Data Sets without the use of a common model underpinning them. This paper outlines these problems like incompatible basic data types and overlapping and incompatible definitions of clinical content. A solution to this based on openEHR archetypes is motivated and an approach to transform existing Clinical Data Sets into archetypes is presented. To avoid significant overlaps and unnecessary effort during archetype development, archetype development needs to be coordinated nationwide and beyond and also across the various health professions in a formalized process.

  7. All high Tc edge-geometry weak links utilizing Y-Ba-Cu-O barrier layers

    NASA Technical Reports Server (NTRS)

    Hunt, B. D.; Foote, M. C.; Bajuk, L. J.

    1991-01-01

    High quality YBa2Cu3O(7-x) normal-metal/YBa2Cu3O(7-x) edge-geometry weak links have been fabricated using nonsuperconducting Y-Ba-Cu-O barrier layers deposited by laser ablation at reduced growth temperatures. Devices incorporating 25-100 A thick barrier layers exhibit current-voltage characteristics consistent with the resistively shunted junction model, with strong microwave and magnetic field response at temperatures up to 85 K. The critical currents vary exponentially with barrier thickness, and the resistances scale linearly with Y-Ba-Cu-O interlayer thickness and device area, indicating good barrier uniformity, with an effective mormal metal coherence length of 20 A.

  8. Privacy Policy Enforcement for Ambient Ubiquitous Services

    NASA Astrophysics Data System (ADS)

    Oyomno, Were; Jäppinen, Pekka; Kerttula, Esa

    Ubiquitous service providers leverage miniaturised computing terminals equipped with wireless capabilities to avail new service models. These models are pivoted on personal and inexpensive terminals to customise services to individual preferences. Portability, small sizes and compact keyboards are few features popularising mobile terminals. Features enable storing and carrying of ever increasing proportions of personal data and ability to use them in service adaptations. Ubiquitous services automate deeper soliciting of personal data transparently without the need for user interactions. Transparent solicitations, acquisitions and handling of personal data legitimises privacy concerns regarding disclosures, retention and re-use of the data. This study presents a policy enforcement for ubiquitous services that safeguards handling of users personal data and monitors adherence to stipulated privacy policies. Enforcement structures towards usability and scalability are presented.

  9. Definition and evaluation of the data-link layer of PACnet

    NASA Astrophysics Data System (ADS)

    Alsafadi, Yasser H.; Martinez, Ralph; Sanders, William H.

    1991-07-01

    PACnet is a 200-500 Mbps dual-ring fiber optic network designed to implement a picture archiving and communication system (PACS) in a hospital environment. The network consists of three channels: an image transfer channel, a command and control channel, and a real-time data channel. An initial network interface unit (NIU) design for PACnet consisted of a functional description of the protocols and NIU major components. In order to develop a demonstration prototype, additional definition of protocol algorithms of each channel is necessary. Using the International Standards Organization/Open Systems Interconnection (ISO/OSI) reference model as a guide, the definition of the data link layer is extended. This definition covers interface service specifications for the two constituent sublayers: logical link control (LLC) and medium access control (MAC). Furthermore, it describes procedures for data transfer, mechanisms of error detection and fault recovery. A performance evaluation study was then made to determine how the network performs under various application scenarios. The performance evaluation study was performed using stochastic activity networks, which can formally describe the network behavior. The results of the study demonstrate the feasibility of PACnet as an integrated image, data, and voice network for PACS.

  10. SignaLink 2 – a signaling pathway resource with multi-layered regulatory networks

    PubMed Central

    2013-01-01

    Background Signaling networks in eukaryotes are made up of upstream and downstream subnetworks. The upstream subnetwork contains the intertwined network of signaling pathways, while the downstream regulatory part contains transcription factors and their binding sites on the DNA as well as microRNAs and their mRNA targets. Currently, most signaling and regulatory databases contain only a subsection of this network, making comprehensive analyses highly time-consuming and dependent on specific data handling expertise. The need for detailed mapping of signaling systems is also supported by the fact that several drug development failures were caused by undiscovered cross-talk or regulatory effects of drug targets. We previously created a uniformly curated signaling pathway resource, SignaLink, to facilitate the analysis of pathway cross-talks. Here, we present SignaLink 2, which significantly extends the coverage and applications of its predecessor. Description We developed a novel concept to integrate and utilize different subsections (i.e., layers) of the signaling network. The multi-layered (onion-like) database structure is made up of signaling pathways, their pathway regulators (e.g., scaffold and endocytotic proteins) and modifier enzymes (e.g., phosphatases, ubiquitin ligases), as well as transcriptional and post-transcriptional regulators of all of these components. The user-friendly website allows the interactive exploration of how each signaling protein is regulated. The customizable download page enables the analysis of any user-specified part of the signaling network. Compared to other signaling resources, distinctive features of SignaLink 2 are the following: 1) it involves experimental data not only from humans but from two invertebrate model organisms, C. elegans and D. melanogaster; 2) combines manual curation with large-scale datasets; 3) provides confidence scores for each interaction; 4) operates a customizable download page with multiple file formats

  11. A Brief Survey of Media Access Control, Data Link Layer, and Protocol Technologies for Lunar Surface Communications

    NASA Technical Reports Server (NTRS)

    Wallett, Thomas M.

    2009-01-01

    This paper surveys and describes some of the existing media access control and data link layer technologies for possible application in lunar surface communications and the advanced wideband Direct Sequence Code Division Multiple Access (DSCDMA) conceptual systems utilizing phased-array technology that will evolve in the next decade. Time Domain Multiple Access (TDMA) and Code Division Multiple Access (CDMA) are standard Media Access Control (MAC) techniques that can be incorporated into lunar surface communications architectures. Another novel hybrid technique that is recently being developed for use with smart antenna technology combines the advantages of CDMA with those of TDMA. The relatively new and sundry wireless LAN data link layer protocols that are continually under development offer distinct advantages for lunar surface applications over the legacy protocols which are not wireless. Also several communication transport and routing protocols can be chosen with characteristics commensurate with smart antenna systems to provide spacecraft communications for links exhibiting high capacity on the surface of the Moon. The proper choices depend on the specific communication requirements.

  12. Trust information-based privacy architecture for ubiquitous health.

    PubMed

    Ruotsalainen, Pekka Sakari; Blobel, Bernd; Seppälä, Antto; Nykänen, Pirkko

    2013-10-08

    Ubiquitous health is defined as a dynamic network of interconnected systems that offers health services independent of time and location to a data subject (DS). The network takes place in open and unsecure information space. It is created and managed by the DS who sets rules that regulate the way personal health information is collected and used. Compared to health care, it is impossible in ubiquitous health to assume the existence of a priori trust between the DS and service providers and to produce privacy using static security services. In ubiquitous health features, business goals and regulations systems followed often remain unknown. Furthermore, health care-specific regulations do not rule the ways health data is processed and shared. To be successful, ubiquitous health requires novel privacy architecture. The goal of this study was to develop a privacy management architecture that helps the DS to create and dynamically manage the network and to maintain information privacy. The architecture should enable the DS to dynamically define service and system-specific rules that regulate the way subject data is processed. The architecture should provide to the DS reliable trust information about systems and assist in the formulation of privacy policies. Furthermore, the architecture should give feedback upon how systems follow the policies of DS and offer protection against privacy and trust threats existing in ubiquitous environments. A sequential method that combines methodologies used in system theory, systems engineering, requirement analysis, and system design was used in the study. In the first phase, principles, trust and privacy models, and viewpoints were selected. Thereafter, functional requirements and services were developed on the basis of a careful analysis of existing research published in journals and conference proceedings. Based on principles, models, and requirements, architectural components and their interconnections were developed using system

  13. Trust Information-Based Privacy Architecture for Ubiquitous Health

    PubMed Central

    2013-01-01

    Background Ubiquitous health is defined as a dynamic network of interconnected systems that offers health services independent of time and location to a data subject (DS). The network takes place in open and unsecure information space. It is created and managed by the DS who sets rules that regulate the way personal health information is collected and used. Compared to health care, it is impossible in ubiquitous health to assume the existence of a priori trust between the DS and service providers and to produce privacy using static security services. In ubiquitous health features, business goals and regulations systems followed often remain unknown. Furthermore, health care-specific regulations do not rule the ways health data is processed and shared. To be successful, ubiquitous health requires novel privacy architecture. Objective The goal of this study was to develop a privacy management architecture that helps the DS to create and dynamically manage the network and to maintain information privacy. The architecture should enable the DS to dynamically define service and system-specific rules that regulate the way subject data is processed. The architecture should provide to the DS reliable trust information about systems and assist in the formulation of privacy policies. Furthermore, the architecture should give feedback upon how systems follow the policies of DS and offer protection against privacy and trust threats existing in ubiquitous environments. Methods A sequential method that combines methodologies used in system theory, systems engineering, requirement analysis, and system design was used in the study. In the first phase, principles, trust and privacy models, and viewpoints were selected. Thereafter, functional requirements and services were developed on the basis of a careful analysis of existing research published in journals and conference proceedings. Based on principles, models, and requirements, architectural components and their interconnections

  14. Mining the preferences of patients for ubiquitous clinic recommendation.

    PubMed

    Chen, Tin-Chih Toly; Chiu, Min-Chi

    2018-03-06

    A challenge facing all ubiquitous clinic recommendation systems is that patients often have difficulty articulating their requirements. To overcome this problem, a ubiquitous clinic recommendation mechanism was designed in this study by mining the clinic preferences of patients. Their preferences were defined using the weights in the ubiquitous clinic recommendation mechanism. An integer nonlinear programming problem was solved to tune the values of the weights on a rolling basis. In addition, since it may take a long time to adjust the values of weights to their asymptotic values, the back propagation network (BPN)-response surface method (RSM) method is applied to estimate the asymptotic values of weights. The proposed methodology was tested in a regional study. Experimental results indicated that the ubiquitous clinic recommendation system outperformed several existing methods in improving the successful recommendation rate.

  15. Construction of Course Ubiquitous Learning Based on Network

    ERIC Educational Resources Information Center

    Wang, Xue; Zhang, Wei; Yang, Xinhui

    2017-01-01

    Ubiquitous learning has been more and more recognized, which describes a new generation of learning from a new point of view. Ubiquitous learning will bring the new teaching practice and teaching reform, which will become an essential way of learning in 21st century. Taking translation course as a case study, this research constructed a system of…

  16. Ubiquitous CM and DM

    NASA Technical Reports Server (NTRS)

    Crowley, Sandra L.

    2000-01-01

    Ubiquitous is a real word. I thank a former Total Quality Coach for my first exposure some years ago to its existence. My version of Webster's dictionary defines ubiquitous as "present, or seeming to be present, everywhere at the same time; omnipresent." While I believe that God is omnipresent, I have come to discover that CM and DM are present everywhere. Oh, yes; I define CM as Configuration Management and DM as either Data or Document Management. Ten years ago, I had my first introduction to the CM world. I had an opportunity to do CM for the Space Station effort at the NASA Lewis Research Center. I learned that CM was a discipline that had four areas of focus: identification, control, status accounting, and verification. I was certified as a CMIl graduate and was indoctrinated about clear, concise, and valid. Off I went into a world of entirely new experiences. I was exposed to change requests and change boards first hand. I also learned about implementation of changes, and then of technical and CM requirements.

  17. Internet messenger based smart virtual class learning using ubiquitous computing

    NASA Astrophysics Data System (ADS)

    Umam, K.; Mardi, S. N. S.; Hariadi, M.

    2017-06-01

    Internet messenger (IM) has become an important educational technology component in college education, IM makes it possible for students to engage in learning and collaborating at smart virtual class learning (SVCL) using ubiquitous computing. However, the model of IM-based smart virtual class learning using ubiquitous computing and empirical evidence that would favor a broad application to improve engagement and behavior are still limited. In addition, the expectation that IM based SVCL using ubiquitous computing could improve engagement and behavior on smart class cannot be confirmed because the majority of the reviewed studies followed instructions paradigms. This article aims to present the model of IM-based SVCL using ubiquitous computing and showing learners’ experiences in improved engagement and behavior for learner-learner and learner-lecturer interactions. The method applied in this paper includes design process and quantitative analysis techniques, with the purpose of identifying scenarios of ubiquitous computing and realize the impressions of learners and lecturers about engagement and behavior aspect and its contribution to learning

  18. Implications of Ubiquitous Computing for the Social Studies Curriculum

    ERIC Educational Resources Information Center

    van Hover, Stephanie D.; Berson, Michael J.; Bolick, Cheryl Mason; Swan, Kathleen Owings

    2004-01-01

    In March 2002, members of the National Technology Leadership Initiative (NTLI) met in Charlottesville, Virginia to discuss the potential effects of ubiquitous computing on the field of education. Ubiquitous computing, or "on-demand availability of task-necessary computing power," involves providing every student with a handheld computer--a…

  19. Socio-technical Issues for Ubiquitous Information Society in 2010

    NASA Astrophysics Data System (ADS)

    Funabashi, Motohisa; Homma, Koichi; Sasaki, Toshiro; Sato, Yoshinori; Kido, Kunihiko; Fukumoto, Takashi; Yano, Koujin

    Impact of the ubiquitous information technology on our society is so significant that directing technological development and preparing institutional apparatus are quite important and urgent. The present paper elaborates, with the efforts by both humanity and engineering disciplines, to find out the socio-technical issues of ubiquitous information society in 2010 by inspecting social implications of emerging technology as well as social expectations. In order to deliberate the issues, scenarios are developed that describes possible life in ubiquitous information society. The derived issues cover integrating information technology and human body, producing smart sharable environment, protecting individual rights, fostering new service business, and forming community.

  20. Trust models in ubiquitous computing.

    PubMed

    Krukow, Karl; Nielsen, Mogens; Sassone, Vladimiro

    2008-10-28

    We recapture some of the arguments for trust-based technologies in ubiquitous computing, followed by a brief survey of some of the models of trust that have been introduced in this respect. Based on this, we argue for the need of more formal and foundational trust models.

  1. The Status of Ubiquitous Computing.

    ERIC Educational Resources Information Center

    Brown, David G.; Petitto, Karen R.

    2003-01-01

    Explains the prevalence and rationale of ubiquitous computing on college campuses--teaching with the assumption or expectation that all faculty and students have access to the Internet--and offers lessons learned by pioneering institutions. Lessons learned involve planning, technology, implementation and management, adoption of computer-enhanced…

  2. Role of Passive Capturing in a Ubiquitous Learning Environment

    ERIC Educational Resources Information Center

    Ogata, Hiroaki; Hou, Bin; Li, MengMeng; Uosaki, Noriko; Mouri, Kousuke

    2013-01-01

    Ubiquitous Learning Log (ULL) is defined as a digital record of what you have learned in the daily life using ubiquitous technologies. This paper focuses on how to capture learning experiences in our daily life for vocabulary learning. In our previous works, we developed a system named SCROLL (System for Capturing and Reminding Of Learning Log) in…

  3. Ubiquitous Learning Project Using Life-Logging Technology in Japan

    ERIC Educational Resources Information Center

    Ogata, Hiroaki; Hou, Bin; Li, Mengmeng; Uosaki, Noriko; Mouri, Kosuke; Liu, Songran

    2014-01-01

    A Ubiquitous Learning Log (ULL) is defined as a digital record of what a learner has learned in daily life using ubiquitous computing technologies. In this paper, a project which developed a system called SCROLL (System for Capturing and Reusing Of Learning Log) is presented. The aim of developing SCROLL is to help learners record, organize,…

  4. A Rhomboid Protease Gene Deletion Affects a Novel Oligosaccharide N-Linked to the S-layer Glycoprotein of Haloferax volcanii*

    PubMed Central

    Parente, Juliana; Casabuono, Adriana; Ferrari, María Celeste; Paggi, Roberto Alejandro; De Castro, Rosana Esther; Couto, Alicia Susana; Giménez, María Inés

    2014-01-01

    Rhomboid proteases occur in all domains of life; however, their physiological role is not completely understood, and nothing is known of the biology of these enzymes in Archaea. One of the two rhomboid homologs of Haloferax volcanii (RhoII) is fused to a zinc finger domain. Chromosomal deletion of rhoII was successful, indicating that this gene is not essential for this organism; however, the mutant strain (MIG1) showed reduced motility and increased sensitivity to novobiocin. Membrane preparations of MIG1 were enriched in two glycoproteins, identified as the S-layer glycoprotein and an ABC transporter component. The H. volcanii S-layer glycoprotein has been extensively used as a model to study haloarchaeal protein N-glycosylation. HPLC analysis of oligosaccharides released from the S-layer glycoprotein after PNGase treatment revealed that MIG1 was enriched in species with lower retention times than those derived from the parent strain. Mass spectrometry analysis showed that the wild type glycoprotein released a novel oligosaccharide species corresponding to GlcNAc-GlcNAc(Hex)2-(SQ-Hex)6 in contrast to the mutant protein, which contained the shorter form GlcNAc2(Hex)2-SQ-Hex-SQ. A glycoproteomics approach of the wild type glycopeptide fraction revealed Asn-732 peptide fragments linked to the sulfoquinovose-containing oligosaccharide. This work describes a novel N-linked oligosaccharide containing a repeating SQ-Hex unit bound to Asn-732 of the H. volcanii S-layer glycoprotein, a position that had not been reported as glycosylated. Furthermore, this study provides the first insight on the biological role of rhomboid proteases in Archaea, suggesting a link between protein glycosylation and this protease family. PMID:24596091

  5. A rhomboid protease gene deletion affects a novel oligosaccharide N-linked to the S-layer glycoprotein of Haloferax volcanii.

    PubMed

    Parente, Juliana; Casabuono, Adriana; Ferrari, María Celeste; Paggi, Roberto Alejandro; De Castro, Rosana Esther; Couto, Alicia Susana; Giménez, María Inés

    2014-04-18

    Rhomboid proteases occur in all domains of life; however, their physiological role is not completely understood, and nothing is known of the biology of these enzymes in Archaea. One of the two rhomboid homologs of Haloferax volcanii (RhoII) is fused to a zinc finger domain. Chromosomal deletion of rhoII was successful, indicating that this gene is not essential for this organism; however, the mutant strain (MIG1) showed reduced motility and increased sensitivity to novobiocin. Membrane preparations of MIG1 were enriched in two glycoproteins, identified as the S-layer glycoprotein and an ABC transporter component. The H. volcanii S-layer glycoprotein has been extensively used as a model to study haloarchaeal protein N-glycosylation. HPLC analysis of oligosaccharides released from the S-layer glycoprotein after PNGase treatment revealed that MIG1 was enriched in species with lower retention times than those derived from the parent strain. Mass spectrometry analysis showed that the wild type glycoprotein released a novel oligosaccharide species corresponding to GlcNAc-GlcNAc(Hex)2-(SQ-Hex)6 in contrast to the mutant protein, which contained the shorter form GlcNAc2(Hex)2-SQ-Hex-SQ. A glycoproteomics approach of the wild type glycopeptide fraction revealed Asn-732 peptide fragments linked to the sulfoquinovose-containing oligosaccharide. This work describes a novel N-linked oligosaccharide containing a repeating SQ-Hex unit bound to Asn-732 of the H. volcanii S-layer glycoprotein, a position that had not been reported as glycosylated. Furthermore, this study provides the first insight on the biological role of rhomboid proteases in Archaea, suggesting a link between protein glycosylation and this protease family.

  6. Finalizing the CCSDS Space-Data Link Layer Security Protocol: Setup and Execution of the Interoperability Testing

    NASA Technical Reports Server (NTRS)

    Fischer, Daniel; Aguilar-Sanchez, Ignacio; Saba, Bruno; Moury, Gilles; Biggerstaff, Craig; Bailey, Brandon; Weiss, Howard; Pilgram, Martin; Richter, Dorothea

    2015-01-01

    The protection of data transmitted over the space-link is an issue of growing importance also for civilian space missions. Through the Consultative Committee for Space Data Systems (CCSDS), space agencies have reacted to this need by specifying the Space Data-Link Layer Security (SDLS) protocol which provides confidentiality and integrity services for the CCSDS Telemetry (TM), Telecommand (TC) and Advanced Orbiting Services (AOS) space data-link protocols. This paper describes the approach of the CCSDS SDLS working group to specify and execute the necessary interoperability tests. It first details the individual SDLS implementations that have been produced by ESA, NASA, and CNES and then the overall architecture that allows the interoperability tests between them. The paper reports on the results of the interoperability tests and identifies relevant aspects for the evolution of the test environment.

  7. Multimodal and ubiquitous computing systems: supporting independent-living older users.

    PubMed

    Perry, Mark; Dowdall, Alan; Lines, Lorna; Hone, Kate

    2004-09-01

    We document the rationale and design of a multimodal interface to a pervasive/ubiquitous computing system that supports independent living by older people in their own homes. The Millennium Home system involves fitting a resident's home with sensors--these sensors can be used to trigger sequences of interaction with the resident to warn them about dangerous events, or to check if they need external help. We draw lessons from the design process and conclude the paper with implications for the design of multimodal interfaces to ubiquitous systems developed for the elderly and in healthcare, as well as for more general ubiquitous computing applications.

  8. A model for ubiquitous care of noncommunicable diseases.

    PubMed

    Vianna, Henrique Damasceno; Barbosa, Jorge Luis Victória

    2014-09-01

    The ubiquitous computing, or ubicomp, is a promising technology to help chronic diseases patients managing activities, offering support to them anytime, anywhere. Hence, ubicomp can aid community and health organizations to continuously communicate with patients and to offer useful resources for their self-management activities. Communication is prioritized in works of ubiquitous health for noncommunicable diseases care, but the management of resources is not commonly employed. We propose the UDuctor, a model for ubiquitous care of noncommunicable diseases. UDuctor focuses the resources offering, without losing self-management and communication supports. We implemented a system and applied it in two practical experiments. First, ten chronic patients tried the system and filled out a questionnaire based on the technology acceptance model. After this initial evaluation, an alpha test was done. The system was used daily for one month and a half by a chronic patient. The results were encouraging and show potential for implementing UDuctor in real-life situations.

  9. Navigation studies based on the ubiquitous positioning technologies

    NASA Astrophysics Data System (ADS)

    Ye, Lei; Mi, Weijie; Wang, Defeng

    2007-11-01

    This paper summarized the nowadays positioning technologies, such as absolute positioning methods and relative positioning methods, indoor positioning and outdoor positioning, active positioning and passive positioning. Global Navigation Satellite System (GNSS) technologies were introduced as the omnipresent out-door positioning technologies, including GPS, GLONASS, Galileo and BD-1/2. After analysis of the shortcomings of GNSS, indoor positioning technologies were discussed and compared, including A-GPS, Cellular network, Infrared, Electromagnetism, Computer Vision Cognition, Embedded Pressure Sensor, Ultrasonic, RFID (Radio Frequency IDentification), Bluetooth, WLAN etc.. Then the concept and characteristics of Ubiquitous Positioning was proposed. After the ubiquitous positioning technologies contrast and selection followed by system engineering methodology, a navigation system model based on Incorporate Indoor-Outdoor Positioning Solution was proposed. And this model was simulated in the Galileo Demonstration for World Expo Shanghai project. In the conclusion, the prospects of ubiquitous positioning based navigation were shown, especially to satisfy the public location information acquiring requirement.

  10. The Effects of Differential Training Procedures on Linked Perceptual Class Formation

    ERIC Educational Resources Information Center

    Fields, Lanny; Tittelbach, Danielle; Shamoun, Kimberly; Watanabe, Mari; Fitzer, Adrienne; Matneja, Priya

    2007-01-01

    When the stimuli in one perceptual class (A') become related to the stimuli in another perceptual class (B'), the two are functioning as a single "linked perceptual class". A common linked perceptual class would be the sounds of a person's voice (class A') and the pictures of that person (class B'). Such classes are ubiquitous in real…

  11. Linked Registries: Connecting Rare Diseases Patient Registries through a Semantic Web Layer

    PubMed Central

    González-Castro, Lorena; Carta, Claudio; van der Horst, Eelke; Lopes, Pedro; Kaliyaperumal, Rajaram; Thompson, Mark; Thompson, Rachel; Queralt-Rosinach, Núria; Lopez, Estrella; Wood, Libby; Robertson, Agata; Lamanna, Claudia; Gilling, Mette; Orth, Michael; Merino-Martinez, Roxana; Taruscio, Domenica; Lochmüller, Hanns

    2017-01-01

    Patient registries are an essential tool to increase current knowledge regarding rare diseases. Understanding these data is a vital step to improve patient treatments and to create the most adequate tools for personalized medicine. However, the growing number of disease-specific patient registries brings also new technical challenges. Usually, these systems are developed as closed data silos, with independent formats and models, lacking comprehensive mechanisms to enable data sharing. To tackle these challenges, we developed a Semantic Web based solution that allows connecting distributed and heterogeneous registries, enabling the federation of knowledge between multiple independent environments. This semantic layer creates a holistic view over a set of anonymised registries, supporting semantic data representation, integrated access, and querying. The implemented system gave us the opportunity to answer challenging questions across disperse rare disease patient registries. The interconnection between those registries using Semantic Web technologies benefits our final solution in a way that we can query single or multiple instances according to our needs. The outcome is a unique semantic layer, connecting miscellaneous registries and delivering a lightweight holistic perspective over the wealth of knowledge stemming from linked rare disease patient registries. PMID:29214177

  12. Linked Registries: Connecting Rare Diseases Patient Registries through a Semantic Web Layer.

    PubMed

    Sernadela, Pedro; González-Castro, Lorena; Carta, Claudio; van der Horst, Eelke; Lopes, Pedro; Kaliyaperumal, Rajaram; Thompson, Mark; Thompson, Rachel; Queralt-Rosinach, Núria; Lopez, Estrella; Wood, Libby; Robertson, Agata; Lamanna, Claudia; Gilling, Mette; Orth, Michael; Merino-Martinez, Roxana; Posada, Manuel; Taruscio, Domenica; Lochmüller, Hanns; Robinson, Peter; Roos, Marco; Oliveira, José Luís

    2017-01-01

    Patient registries are an essential tool to increase current knowledge regarding rare diseases. Understanding these data is a vital step to improve patient treatments and to create the most adequate tools for personalized medicine. However, the growing number of disease-specific patient registries brings also new technical challenges. Usually, these systems are developed as closed data silos, with independent formats and models, lacking comprehensive mechanisms to enable data sharing. To tackle these challenges, we developed a Semantic Web based solution that allows connecting distributed and heterogeneous registries, enabling the federation of knowledge between multiple independent environments. This semantic layer creates a holistic view over a set of anonymised registries, supporting semantic data representation, integrated access, and querying. The implemented system gave us the opportunity to answer challenging questions across disperse rare disease patient registries. The interconnection between those registries using Semantic Web technologies benefits our final solution in a way that we can query single or multiple instances according to our needs. The outcome is a unique semantic layer, connecting miscellaneous registries and delivering a lightweight holistic perspective over the wealth of knowledge stemming from linked rare disease patient registries.

  13. Use of Ubiquitous Technologies in Military Logistic System in Iran

    NASA Astrophysics Data System (ADS)

    Jafari, P.; Sadeghi-Niaraki, A.

    2013-09-01

    This study is about integration and evaluation of RFID and ubiquitous technologies in military logistic system management. Firstly, supply chain management and the necessity of a revolution in logistic systems especially in military area, are explained. Secondly RFID and ubiquitous technologies and the advantages of their use in supply chain management are introduced. Lastly a system based on these technologies for controlling and increasing the speed and accuracy in military logistic system in Iran with its unique properties, is presented. The system is based on full control of military logistics (supplies) from the time of deployment to replenishment using sensor network, ubiquitous and RFID technologies.

  14. Ubiquitous Computing: The Universal Use of Computers on College Campuses.

    ERIC Educational Resources Information Center

    Brown, David G., Ed.

    This book is a collection of vignettes from 13 universities where everyone on campus has his or her own computer. These 13 institutions have instituted "ubiquitous computing" in very different ways at very different costs. The chapters are: (1) "Introduction: The Ubiquitous Computing Movement" (David G. Brown); (2) "Dartmouth College" (Malcolm…

  15. Ubiquitous Learning: Determinants Impacting Learners' Satisfaction and Performance with Smartphones

    ERIC Educational Resources Information Center

    Jung, Hee-Jung

    2014-01-01

    Although the concept of ubiquitous technologies has been introduced to many parts of society, there have been limited applications, and little is known about learners' behavior toward ubiquitous technologies, particularly in the context of English learning. This study considers a sample of Korean students to identify the key factors that influence…

  16. Amide Link Scission in the Polyamide Active Layers of Thin-Film Composite Membranes upon Exposure to Free Chlorine: Kinetics and Mechanisms.

    PubMed

    Powell, Joshua; Luh, Jeanne; Coronell, Orlando

    2015-10-20

    The volume-averaged amide link scission in the aromatic polyamide active layer of a reverse osmosis membrane upon exposure to free chlorine was quantified at a variety of free chlorine exposure times, concentrations, and pH and rinsing conditions. The results showed that (i) hydroxyl ions are needed for scission to occur, (ii) hydroxide-induced amide link scission is a strong function of exposure to hypochlorous acid, (iii) the ratio between amide links broken and chlorine atoms taken up increased with the chlorination pH and reached a maximum of ∼25%, (iv) polyamide disintegration occurs when high free chlorine concentrations, alkaline conditions, and high exposure times are combined, (v) amide link scission promotes further chlorine uptake, and (vi) scission at the membrane surface is unrepresentative of volume-averaged scission in the active layer. Our observations are consistent with previously proposed mechanisms describing amide link scission as a result of the hydrolysis of the N-chlorinated amidic N-C bond due to nucleophilic attack by hydroxyl ions. This study increases the understanding of the physicochemical changes that could occur for membranes in treatment plants using chlorine as an upstream disinfectant and the extent and rate at which those changes would occur.

  17. Ubiquitous technologies in health: new challenges of opportunity, expectation, and responsibility.

    PubMed

    Rigby, Michael

    2006-01-01

    In spite of their name, 'ubiquitous' technologies are not yet ubiquitous in the true sense of the word, but rather are 'novel', being at the research, pilot, and selective use stages. In future, the proliferation in types of application, the major increase in cases and data volumes, and above all the dependence on ubiquitous technologies will raise practical, ethical, and liability issues. Equally significantly, it will require health service redesign, including new response services. Health informaticians need to be active in stimulating consideration of all these issues, as part of both social and professional responsibility.

  18. An improved anonymous authentication scheme for roaming in ubiquitous networks.

    PubMed

    Lee, Hakjun; Lee, Donghoon; Moon, Jongho; Jung, Jaewook; Kang, Dongwoo; Kim, Hyoungshick; Won, Dongho

    2018-01-01

    With the evolution of communication technology and the exponential increase of mobile devices, the ubiquitous networking allows people to use our data and computing resources anytime and everywhere. However, numerous security concerns and complicated requirements arise as these ubiquitous networks are deployed throughout people's lives. To meet the challenge, the user authentication schemes in ubiquitous networks should ensure the essential security properties for the preservation of the privacy with low computational cost. In 2017, Chaudhry et al. proposed a password-based authentication scheme for the roaming in ubiquitous networks to enhance the security. Unfortunately, we found that their scheme remains insecure in its protection of the user privacy. In this paper, we prove that Chaudhry et al.'s scheme is vulnerable to the stolen-mobile device and user impersonation attacks, and its drawbacks comprise the absence of the incorrect login-input detection, the incorrectness of the password change phase, and the absence of the revocation provision. Moreover, we suggest a possible way to fix the security flaw in Chaudhry et al's scheme by using the biometric-based authentication for which the bio-hash is applied in the implementation of a three-factor authentication. We prove the security of the proposed scheme with the random oracle model and formally verify its security properties using a tool named ProVerif, and analyze it in terms of the computational and communication cost. The analysis result shows that the proposed scheme is suitable for resource-constrained ubiquitous environments.

  19. Context Aware Ubiquitous Learning Environments for Peer-to-Peer Collaborative Learning

    ERIC Educational Resources Information Center

    Yang, Stephen J. H.

    2006-01-01

    A ubiquitous learning environment provides an interoperable, pervasive, and seamless learning architecture to connect, integrate, and share three major dimensions of learning resources: learning collaborators, learning contents, and learning services. Ubiquitous learning is characterized by providing intuitive ways for identifying right learning…

  20. Printable polymer actuators from ionic liquid, soluble polyimide, and ubiquitous carbon materials.

    PubMed

    Imaizumi, Satoru; Ohtsuki, Yuto; Yasuda, Tomohiro; Kokubo, Hisashi; Watanabe, Masayoshi

    2013-07-10

    We present here printable high-performance polymer actuators comprising ionic liquid (IL), soluble polyimide, and ubiquitous carbon materials. Polymer electrolytes with high ionic conductivity and reliable mechanical strength are required for high-performance polymer actuators. The developed polymer electrolytes comprised a soluble sulfonated polyimide (SPI) and IL, 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)amide ([C2mim][NTf2]), and they exhibited acceptable ionic conductivity up to 1 × 10(-3) S cm(-1) and favorable mechanical properties (elastic modulus >1 × 10(7) Pa). Polymer actuators based on SPI/[C2mim][NTf2] electrolytes were prepared using inexpensive activated carbon (AC) together with highly electron-conducting carbon such as acetylene black (AB), vapor grown carbon fiber (VGCF), and Ketjen black (KB). The resulting polymer actuators have a trilaminar electric double-layer capacitor structure, consisting of a polymer electrolyte layer sandwiched between carbon electrode layers. Displacement, response speed, and durability of the actuators depended on the combination of carbons. Especially the actuators with mixed AC/KB carbon electrodes exhibited relatively large displacement and high-speed response, and they kept 80% of the initial displacement even after more than 5000 cycles. The generated force of the actuators correlated with the elastic modulus of SPI/[C2mim][NTf2] electrolytes. The displacement of the actuators was proportional to the accumulated electric charge in the electrodes, regardless of carbon materials, and agreed well with the previously proposed displacement model.

  1. An improved anonymous authentication scheme for roaming in ubiquitous networks

    PubMed Central

    Lee, Hakjun; Lee, Donghoon; Moon, Jongho; Jung, Jaewook; Kang, Dongwoo; Kim, Hyoungshick

    2018-01-01

    With the evolution of communication technology and the exponential increase of mobile devices, the ubiquitous networking allows people to use our data and computing resources anytime and everywhere. However, numerous security concerns and complicated requirements arise as these ubiquitous networks are deployed throughout people’s lives. To meet the challenge, the user authentication schemes in ubiquitous networks should ensure the essential security properties for the preservation of the privacy with low computational cost. In 2017, Chaudhry et al. proposed a password-based authentication scheme for the roaming in ubiquitous networks to enhance the security. Unfortunately, we found that their scheme remains insecure in its protection of the user privacy. In this paper, we prove that Chaudhry et al.’s scheme is vulnerable to the stolen-mobile device and user impersonation attacks, and its drawbacks comprise the absence of the incorrect login-input detection, the incorrectness of the password change phase, and the absence of the revocation provision. Moreover, we suggest a possible way to fix the security flaw in Chaudhry et al’s scheme by using the biometric-based authentication for which the bio-hash is applied in the implementation of a three-factor authentication. We prove the security of the proposed scheme with the random oracle model and formally verify its security properties using a tool named ProVerif, and analyze it in terms of the computational and communication cost. The analysis result shows that the proposed scheme is suitable for resource-constrained ubiquitous environments. PMID:29505575

  2. Ubiquitous Robotic Technology for Smart Manufacturing System.

    PubMed

    Wang, Wenshan; Zhu, Xiaoxiao; Wang, Liyu; Qiu, Qiang; Cao, Qixin

    2016-01-01

    As the manufacturing tasks become more individualized and more flexible, the machines in smart factory are required to do variable tasks collaboratively without reprogramming. This paper for the first time discusses the similarity between smart manufacturing systems and the ubiquitous robotic systems and makes an effort on deploying ubiquitous robotic technology to the smart factory. Specifically, a component based framework is proposed in order to enable the communication and cooperation of the heterogeneous robotic devices. Further, compared to the service robotic domain, the smart manufacturing systems are often in larger size. So a hierarchical planning method was implemented to improve the planning efficiency. A test bed of smart factory is developed. It demonstrates that the proposed framework is suitable for industrial domain, and the hierarchical planning method is able to solve large problems intractable with flat methods.

  3. Ubiquitous Robotic Technology for Smart Manufacturing System

    PubMed Central

    Zhu, Xiaoxiao; Wang, Liyu; Qiu, Qiang; Cao, Qixin

    2016-01-01

    As the manufacturing tasks become more individualized and more flexible, the machines in smart factory are required to do variable tasks collaboratively without reprogramming. This paper for the first time discusses the similarity between smart manufacturing systems and the ubiquitous robotic systems and makes an effort on deploying ubiquitous robotic technology to the smart factory. Specifically, a component based framework is proposed in order to enable the communication and cooperation of the heterogeneous robotic devices. Further, compared to the service robotic domain, the smart manufacturing systems are often in larger size. So a hierarchical planning method was implemented to improve the planning efficiency. A test bed of smart factory is developed. It demonstrates that the proposed framework is suitable for industrial domain, and the hierarchical planning method is able to solve large problems intractable with flat methods. PMID:27446206

  4. U-ALS: A Ubiquitous Learning Environment

    ERIC Educational Resources Information Center

    Piovesan, Sandra Dutra; Passerino, Liliana Maria; Medina, Roseclea Duarte

    2012-01-01

    The diffusion of the use of the learning virtual environments presents a great potential for the development of an application which meet the necessities in the education area. In view of the importance of a more dynamic application and that can adapt itself continuously to the students' necessities, the "U-ALS" (Ubiquitous Adapted Learning…

  5. Analysis of energy efficient routing protocols for implementation of a ubiquitous health system

    NASA Astrophysics Data System (ADS)

    Kwon, Jongwon; Park, Yongman; Koo, Sangjun; Ayurzana, Odgeral; Kim, Hiesik

    2007-12-01

    The innovative Ubiquitous-Health was born through convergence of medical service, with development of up to date information technologies and ubiquitous IT. The U-Health can be applied to a variety of special situations for managing functions of each medical center efficiently. This paper focuses on estimation of various routing protocols for implementation of U-health monitoring system. In order to facilitate wireless communication over the network, a routing protocol on the network layer is used to establish precise and efficient route between sensor nodes so that information acquired from sensors may be delivered in a timely manner. A route establishment should be considered to minimize overhead, data loss and power consumption because wireless networks for U-health are organized by a large number of sensor nodes which are small in size and have limited processing power, memory and battery life. In this paper a overview of wireless sensor network technologies commonly known is described as well as evaluation of three multi hop routing protocols which are flooding, gossiping and modified low energy adaptive clustering hierarchy(LEACH) for use with these networks using TOSSIM simulator. As a result of evaluation the integrated wireless sensor board was developed in particular. The board is embedded device based on AVR128 porting TinyOS. Also it employs bio sensor measures blood pressure, pulse frequency and ZigBee module for wireless communication. This paper accelerates the digital convergence age through continual research and development of technologies related the U-Health.

  6. Using Context-Aware Ubiquitous Learning to Support Students' Understanding of Geometry

    ERIC Educational Resources Information Center

    Crompton, Helen

    2015-01-01

    In this study, context-aware ubiquitous learning was used to support 4th grade students as they learn angle concepts. Context-aware ubiquitous learning was provided to students primarily through the use of iPads to access real-world connections and a Dynamic Geometry Environment. Gravemeijer and van Eerde's (2009), design-based research (DBR)…

  7. A Link-Level Simulator of the cdma2000 Reverse-Link Physical Layer

    PubMed Central

    Gharavi, H.; Chin, F.; Ban, K.; Wyatt-Millington, R.

    2003-01-01

    The cdma2000 system is an evolutionary enhancement of the IS-95 standards which support 3G services defined by the International Telecommunications Union (ITU). cdma2000 comes in two phases: 1XRTT and 3XRTT (1X and 3X indicates the number of 1.25 MHz wide radio carrier channels used and RTT stands for Radio Transmission Technology). The cdma2000 1XRTT, which operates within a 1.25 MHz bandwidth, can be utilized in existing IS-95 CDMA channels as it uses the same bandwidth, while 3XRTT requires the commitment of 5 MHz bandwidth to support higher data rates. This paper describes a software model implementation of the cdma2000 reverse link and its application for evaluating the effect of rake receiver design parameters on the system performance under various multipath fading conditions. The cdma2000 models were developed at the National Institute of Standards and Technology (NIST), using SPW (Signal Processing Worksystem) commercial software tools. The model has been developed in a generic manner that includes all the reverse link six radio configurations and their corresponding data rates, according to cdma2000 specifications. After briefly reviewing the traffic channel characteristics of the cdma2000 reverse link (subscriber to base station), the paper discusses the rake receiver implementation including an ideal rake receiver. It then evaluates the performance of each receiver for a Spreading Rate 3 (3XRTT) operation, which is considered as a true “3G” cdma2000 technology. These evaluations are based on the vehicular IMT-2000 (International Mobile Telecommunication 2000) channel model using the link budget defined in cdma2000 specifications for the reverse link. PMID:27413613

  8. Social Media, Open Science, and Data Science Are Inextricably Linked.

    PubMed

    Voytek, Bradley

    2017-12-20

    Should scientists use social media? Why practice open science? What is data science? Ten years ago, these phrases hardly existed. Now they are ubiquitous. Here I argue that these phenomena are inextricably linked and reflect similar underlying social and technological transformations. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. After Installation: Ubiquitous Computing and High School Science in Three Experienced, High-Technology Schools

    ERIC Educational Resources Information Center

    Drayton, Brian; Falk, Joni K.; Stroud, Rena; Hobbs, Kathryn; Hammerman, James

    2010-01-01

    There are few studies of the impact of ubiquitous computing on high school science, and the majority of studies of ubiquitous computing report only on the early stages of implementation. The present study presents data on 3 high schools with carefully elaborated ubiquitous computing systems that have gone through at least one "obsolescence cycle"…

  10. A seamless ubiquitous emergency medical service for crisis situations.

    PubMed

    Lin, Bor-Shing

    2016-04-01

    In crisis situations, a seamless ubiquitous communication is necessary to provide emergency medical service to save people's lives. An excellent prehospital emergency medicine provides immediate medical care to increase the survival rate of patients. On their way to the hospital, ambulance personnel must transmit real-time and uninterrupted patient information to the hospital to apprise the physician of the situation and provide options to the ambulance personnel. In emergency and crisis situations, many communication channels can be unserviceable because of damage to equipment or loss of power. Thus, data transmission over wireless communication to achieve uninterrupted network services is a major obstacle. This study proposes a mobile middleware for cognitive radio (CR) for improving the wireless communication link. CRs can sense their operating environment and optimize the spectrum usage so that the mobile middleware can integrate the existing wireless communication systems with a seamless communication service in heterogeneous network environments. Eventually, the proposed seamless mobile communication middleware was ported into an embedded system, which is compatible with the actual network environment without the need for changing the original system architecture. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  11. From Virtual Environments to Physical Environments: Exploring Interactivity in Ubiquitous-Learning Systems

    ERIC Educational Resources Information Center

    Peng, Hsinyi; Chou, Chien; Chang, Chun-Yu

    2008-01-01

    Computing devices and applications are now used beyond the desktop, in diverse environments, and this trend toward ubiquitous computing is evolving. In this study, we re-visit the interactivity concept and its applications for interactive function design in a ubiquitous-learning system (ULS). Further, we compare interactivity dimensions and…

  12. Ubiquitous Mobile Knowledge Construction in Collaborative Learning Environments

    PubMed Central

    Baloian, Nelson; Zurita, Gustavo

    2012-01-01

    Knowledge management is a critical activity for any organization. It has been said to be a differentiating factor and an important source of competitiveness if this knowledge is constructed and shared among its members, thus creating a learning organization. Knowledge construction is critical for any collaborative organizational learning environment. Nowadays workers must perform knowledge creation tasks while in motion, not just in static physical locations; therefore it is also required that knowledge construction activities be performed in ubiquitous scenarios, and supported by mobile and pervasive computational systems. These knowledge creation systems should help people in or outside organizations convert their tacit knowledge into explicit knowledge, thus supporting the knowledge construction process. Therefore in our understanding, we consider highly relevant that undergraduate university students learn about the knowledge construction process supported by mobile and ubiquitous computing. This has been a little explored issue in this field. This paper presents the design, implementation, and an evaluation of a system called MCKC for Mobile Collaborative Knowledge Construction, supporting collaborative face-to-face tacit knowledge construction and sharing in ubiquitous scenarios. The MCKC system can be used by undergraduate students to learn how to construct knowledge, allowing them anytime and anywhere to create, make explicit and share their knowledge with their co-learners, using visual metaphors, gestures and sketches to implement the human-computer interface of mobile devices (PDAs). PMID:22969333

  13. Ubiquitous mobile knowledge construction in collaborative learning environments.

    PubMed

    Baloian, Nelson; Zurita, Gustavo

    2012-01-01

    Knowledge management is a critical activity for any organization. It has been said to be a differentiating factor and an important source of competitiveness if this knowledge is constructed and shared among its members, thus creating a learning organization. Knowledge construction is critical for any collaborative organizational learning environment. Nowadays workers must perform knowledge creation tasks while in motion, not just in static physical locations; therefore it is also required that knowledge construction activities be performed in ubiquitous scenarios, and supported by mobile and pervasive computational systems. These knowledge creation systems should help people in or outside organizations convert their tacit knowledge into explicit knowledge, thus supporting the knowledge construction process. Therefore in our understanding, we consider highly relevant that undergraduate university students learn about the knowledge construction process supported by mobile and ubiquitous computing. This has been a little explored issue in this field. This paper presents the design, implementation, and an evaluation of a system called MCKC for Mobile Collaborative Knowledge Construction, supporting collaborative face-to-face tacit knowledge construction and sharing in ubiquitous scenarios. The MCKC system can be used by undergraduate students to learn how to construct knowledge, allowing them anytime and anywhere to create, make explicit and share their knowledge with their co-learners, using visual metaphors, gestures and sketches to implement the human-computer interface of mobile devices (PDAs).

  14. Ubiquitous computing in shared-care environments.

    PubMed

    Koch, S

    2006-07-01

    In light of future challenges, such as growing numbers of elderly, increase in chronic diseases, insufficient health care budgets and problems with staff recruitment for the health-care sector, information and communication technology (ICT) becomes a possible means to meet these challenges. Organizational changes such as the decentralization of the health-care system lead to a shift from in-hospital to both advanced and basic home health care. Advanced medical technologies provide solutions for distant home care in form of specialist consultations and home monitoring. Furthermore, the shift towards home health care will increase mobile work and the establishment of shared care teams which require ICT-based solutions that support ubiquitous information access and cooperative work. Clinical documentation and decision support systems are the main ICT-based solutions of interest in the context of ubiquitous computing for shared care environments. This paper therefore describes the prerequisites for clinical documentation and decision support at the point of care, the impact of mobility on the documentation process, and how the introduction of ICT-based solutions will influence organizations and people. Furthermore, the role of dentistry in shared-care environments is discussed and illustrated in the form of a future scenario.

  15. Commentary: Ubiquitous Computing Revisited--A New Perspective

    ERIC Educational Resources Information Center

    Bull, Glen; Garofalo, Joe

    2006-01-01

    In 2002, representatives from the teacher educator associations representing the core content areas (science, mathematics, language arts, and social studies) and educational technology met at the National Technology Leadership Retreat (NTLR) to discuss potential implications of ubiquitous computing for K-12 schools. This paper re-examines some of…

  16. Materials based on carbon-filled porous layers of PVC cyclam derivatives cross-linked with the surfaces of asbestos fabric fibers

    NASA Astrophysics Data System (ADS)

    Tzivadze, A. Yu.; Fridman, A. Ya.; Morozova, E. M.; Sokolova, N. P.; Voloshchuk, A. M.; Petukhova, G. A.; Bardishev, I. I.; Gorbunov, A. M.; Novikov, A. K.; Polyakova, I. Ya.; Titova, V. N.; Yavich, A. A.; Petrova, N. V.

    2016-08-01

    The synthesis of bilayer materials with porous upper layers composed of PVC hydroxyethylcyclam derivatives filled with carbon and a layer consisting of hydroxyethylcyclam, cross-linked via Si-O-C groups with the silica chains of a developed surface of asbestos fabric, is described. The aza-crown groups in these materials are bound with aqua complexes of H2SO4 or NaOH. The structure of the materials is examined, their adsorption characteristics are determined, and the rate of motion of H+ or OH- ions in electrochemical bridges is measured, while the formation of H2 and O2 in their cathodic and anodic polarization is determined as a function of voltage. It is shown that the upper layer of these materials is adsorption-active and electronand H+- or OH-- conductive, while the bottom layer is only H+- or OH-- conductive; through it, the upper layer is supplied with the H+ or OH- ions needed for the regeneration of the aqua complexes broken down to H2 and O2 on carbon particles.

  17. Towards ubiquitous access of computer-assisted surgery systems.

    PubMed

    Liu, Hui; Lufei, Hanping; Shi, Weishong; Chaudhary, Vipin

    2006-01-01

    Traditional stand-alone computer-assisted surgery (CAS) systems impede the ubiquitous and simultaneous access by multiple users. With advances in computing and networking technologies, ubiquitous access to CAS systems becomes possible and promising. Based on our preliminary work, CASMIL, a stand-alone CAS server developed at Wayne State University, we propose a novel mobile CAS system, UbiCAS, which allows surgeons to retrieve, review and interpret multimodal medical images, and to perform some critical neurosurgical procedures on heterogeneous devices from anywhere at anytime. Furthermore, various optimization techniques, including caching, prefetching, pseudo-streaming-model, and compression, are used to guarantee the QoS of the UbiCAS system. UbiCAS enables doctors at remote locations to actively participate remote surgeries, share patient information in real time before, during, and after the surgery.

  18. A Structurally Specialized Uniform Wall Layer is Essential for Constructing Wall Ingrowth Papillae in Transfer Cells

    PubMed Central

    Xia, Xue; Zhang, Hui-Ming; Offler, Christina E.; Patrick, John W.

    2017-01-01

    Transfer cells are characterized by wall labyrinths with either a flange or reticulate architecture. A literature survey established that reticulate wall ingrowth papillae ubiquitously arise from a modified component of their wall labyrinth, termed the uniform wall layer; a structure absent from flange transfer cells. This finding sparked an investigation of the deposition characteristics and role of the uniform wall layer using a Vicia faba cotyledon culture system. On transfer of cotyledons to culture, their adaxial epidermal cells spontaneously trans-differentiate to a reticulate architecture comparable to their abaxial epidermal transfer cell counterparts formed in planta. Uniform wall layer construction commenced once adaxial epidermal cell expansion had ceased to overlay the original outer periclinal wall on its inner surface. In contrast to the dense ring-like lattice of cellulose microfibrils in the original primary wall, the uniform wall layer was characterized by a sparsely dispersed array of linear cellulose microfibrils. A re-modeled cortical microtubule array exerted no influence on uniform wall layer formation or on its cellulose microfibril organization. Surprisingly, formation of the uniform wall layer was not dependent upon depositing a cellulose scaffold. In contrast, uniform wall cellulose microfibrils were essential precursors for constructing wall ingrowth papillae. On converging to form wall ingrowth papillae, the cellulose microfibril diameters increased 3-fold. This event correlated with up-regulated differential, and transfer-cell specific, expression of VfCesA3B while transcript levels of other cellulose biosynthetic-related genes linked with primary wall construction were substantially down-regulated. PMID:29259611

  19. A Structurally Specialized Uniform Wall Layer is Essential for Constructing Wall Ingrowth Papillae in Transfer Cells.

    PubMed

    Xia, Xue; Zhang, Hui-Ming; Offler, Christina E; Patrick, John W

    2017-01-01

    Transfer cells are characterized by wall labyrinths with either a flange or reticulate architecture. A literature survey established that reticulate wall ingrowth papillae ubiquitously arise from a modified component of their wall labyrinth, termed the uniform wall layer; a structure absent from flange transfer cells. This finding sparked an investigation of the deposition characteristics and role of the uniform wall layer using a Vicia faba cotyledon culture system. On transfer of cotyledons to culture, their adaxial epidermal cells spontaneously trans -differentiate to a reticulate architecture comparable to their abaxial epidermal transfer cell counterparts formed in planta . Uniform wall layer construction commenced once adaxial epidermal cell expansion had ceased to overlay the original outer periclinal wall on its inner surface. In contrast to the dense ring-like lattice of cellulose microfibrils in the original primary wall, the uniform wall layer was characterized by a sparsely dispersed array of linear cellulose microfibrils. A re-modeled cortical microtubule array exerted no influence on uniform wall layer formation or on its cellulose microfibril organization. Surprisingly, formation of the uniform wall layer was not dependent upon depositing a cellulose scaffold. In contrast, uniform wall cellulose microfibrils were essential precursors for constructing wall ingrowth papillae. On converging to form wall ingrowth papillae, the cellulose microfibril diameters increased 3-fold. This event correlated with up-regulated differential, and transfer-cell specific, expression of VfCesA3B while transcript levels of other cellulose biosynthetic-related genes linked with primary wall construction were substantially down-regulated.

  20. From Many-to-One to One-to-Many: The Evolution of Ubiquitous Computing in Education

    ERIC Educational Resources Information Center

    Chen, Wenli; Lim, Carolyn; Tan, Ashley

    2011-01-01

    Personal, Internet-connected technologies are becoming ubiquitous in the lives of students, and ubiquitous computing initiatives are already expanding in educational contexts. Historically in the field of education, the terms one-to-one (1:1) computing and ubiquitous computing have been interpreted in a number of ways and have at times been used…

  1. Ubiquitous Accessibility for People with Visual Impairments: Are We There Yet?

    PubMed Central

    Billah, Syed Masum; Ashok, Vikas; Porter, Donald E.; Ramakrishnan, IV

    2017-01-01

    Ubiquitous access is an increasingly common vision of computing, wherein users can interact with any computing device or service from anywhere, at any time. In the era of personal computing, users with visual impairments required special-purpose, assistive technologies, such as screen readers, to interact with computers. This paper investigates whether technologies like screen readers have kept pace with, or have created a barrier to, the trend toward ubiquitous access, with a specific focus on desktop computing as this is still the primary way computers are used in education and employment. Towards that, the paper presents a user study with 21 visually-impaired participants, specifically involving the switching of screen readers within and across different computing platforms, and the use of screen readers in remote access scenarios. Among the findings, the study shows that, even for remote desktop access—an early forerunner of true ubiquitous access—screen readers are too limited, if not unusable. The study also identifies several accessibility needs, such as uniformity of navigational experience across devices, and recommends potential solutions. In summary, assistive technologies have not made the jump into the era of ubiquitous access, and multiple, inconsistent screen readers create new practical problems for users with visual impairments. PMID:28782061

  2. Ubiquitous Accessibility for People with Visual Impairments: Are We There Yet?

    PubMed

    Billah, Syed Masum; Ashok, Vikas; Porter, Donald E; Ramakrishnan, I V

    2017-05-01

    Ubiquitous access is an increasingly common vision of computing, wherein users can interact with any computing device or service from anywhere, at any time. In the era of personal computing, users with visual impairments required special-purpose, assistive technologies, such as screen readers, to interact with computers. This paper investigates whether technologies like screen readers have kept pace with, or have created a barrier to, the trend toward ubiquitous access, with a specific focus on desktop computing as this is still the primary way computers are used in education and employment. Towards that, the paper presents a user study with 21 visually-impaired participants, specifically involving the switching of screen readers within and across different computing platforms, and the use of screen readers in remote access scenarios. Among the findings, the study shows that, even for remote desktop access-an early forerunner of true ubiquitous access-screen readers are too limited, if not unusable. The study also identifies several accessibility needs, such as uniformity of navigational experience across devices, and recommends potential solutions. In summary, assistive technologies have not made the jump into the era of ubiquitous access, and multiple, inconsistent screen readers create new practical problems for users with visual impairments.

  3. Towards Ubiquitous Blood Pressure Monitoring via Pulse Transit Time: Theory and Practice

    PubMed Central

    Hahn, Jin-Oh; Inan, Omer T.; Mestha, Lalit K.; Kim, Chang-Sei; Töreyin, Hakan; Kyal, Survi

    2015-01-01

    Ubiquitous blood pressure (BP) monitoring is needed to improve hypertension detection and control and is becoming feasible due to recent technological advances such as in wearable sensing. Pulse transit time (PTT) represents a well-known, potential approach for ubiquitous BP monitoring. The goal of this review is to facilitate the achievement of reliable, ubiquitous BP monitoring via PTT. We explain the conventional BP measurement methods and their limitations; present models to summarize the theory of the PTT-BP relationship; outline the approach while pinpointing the key challenges; overview the previous work towards putting the theory to practice; make suggestions for best practice and future research; and discuss realistic expectations for the approach. PMID:26057530

  4. Covalent cross-linking as a strategy to generate novel materials based on layered (2D) and other low D structures.

    PubMed

    Rao, C N R; Pramoda, K; Kumar, Ram

    2017-09-12

    Covalent linking of 2D structures such as graphene, MoS 2 and C 3 N 4 by employing coupling reactions provides a strategy to generate a variety of materials with new or improved properties. These materials in a way provide the counter point based on covalent bonds to the van der Waals heterostructures. In this article, we describe materials obtained by linking graphene, MoS 2 and BN with other layered structures and also with one-dimensional nanotubes and zero-dimensional MOFs and MOPs. Novel properties of the materials relate not only to porosity, surface area and gas adsorption, but also to supercapacitor characterstics, mechanical properties and the hydrogen evolution reaction. It should be possible to discover many more interesting structures and materials by employing the cross-linking strategy described here.

  5. Ubiquitous Computing--Are We Crazy? Point/Counterpoint

    ERIC Educational Resources Information Center

    DeWitt, Scott W.; Horn, Patricia S.

    2005-01-01

    The push for ubiquitous computing (UC) relies on an understandable and well-intentioned belief that teaching and schooling need to be transformed. This view appears credible based on large-scale criteria, such as test scores relative to other countries, drop-out rates, and economic changes. And the use of technology to achieve this goal is…

  6. A Ubiquitous English Vocabulary Learning System: Evidence of Active/Passive Attitudes vs. Usefulness/Ease-of-Use

    ERIC Educational Resources Information Center

    Huang, Yueh-Min; Huang, Yong-Ming; Huang, Shu-Hsien; Lin, Yen-Ting

    2012-01-01

    English vocabulary learning and ubiquitous learning have separately received considerable attention in recent years. However, research on English vocabulary learning in ubiquitous learning contexts has been less studied. In this study, we develop a ubiquitous English vocabulary learning (UEVL) system to assist students in experiencing a systematic…

  7. Integrated Environment for Ubiquitous Healthcare and Mobile IPv6 Networks

    NASA Astrophysics Data System (ADS)

    Cagalaban, Giovanni; Kim, Seoksoo

    The development of Internet technologies based on the IPv6 protocol will allow real-time monitoring of people with health deficiencies and improve the independence of elderly people. This paper proposed a ubiquitous healthcare system for the personalized healthcare services with the support of mobile IPv6 networks. Specifically, this paper discusses the integration of ubiquitous healthcare and wireless networks and its functional requirements. This allow an integrated environment where heterogeneous devices such a mobile devices and body sensors can continuously monitor patient status and communicate remotely with healthcare servers, physicians, and family members to effectively deliver healthcare services.

  8. From Learning Object to Learning Cell: A Resource Organization Model for Ubiquitous Learning

    ERIC Educational Resources Information Center

    Yu, Shengquan; Yang, Xianmin; Cheng, Gang

    2013-01-01

    The key to implementing ubiquitous learning is the construction and organization of learning resources. While current research on ubiquitous learning has primarily focused on concept models, supportive environments and small-scale empirical research, exploring ways to organize learning resources to make them available anywhere on-demand is also…

  9. Ubiquitous human upper-limb motion estimation using wearable sensors.

    PubMed

    Zhang, Zhi-Qiang; Wong, Wai-Choong; Wu, Jian-Kang

    2011-07-01

    Human motion capture technologies have been widely used in a wide spectrum of applications, including interactive game and learning, animation, film special effects, health care, navigation, and so on. The existing human motion capture techniques, which use structured multiple high-resolution cameras in a dedicated studio, are complicated and expensive. With the rapid development of microsensors-on-chip, human motion capture using wearable microsensors has become an active research topic. Because of the agility in movement, upper-limb motion estimation has been regarded as the most difficult problem in human motion capture. In this paper, we take the upper limb as our research subject and propose a novel ubiquitous upper-limb motion estimation algorithm, which concentrates on modeling the relationship between upper-arm movement and forearm movement. A link structure with 5 degrees of freedom (DOF) is proposed to model the human upper-limb skeleton structure. Parameters are defined according to Denavit-Hartenberg convention, forward kinematics equations are derived, and an unscented Kalman filter is deployed to estimate the defined parameters. The experimental results have shown that the proposed upper-limb motion capture and analysis algorithm outperforms other fusion methods and provides accurate results in comparison to the BTS optical motion tracker.

  10. Using Ubiquitous Games in an English Listening and Speaking Course: Impact on Learning Outcomes and Motivation

    ERIC Educational Resources Information Center

    Liu, Tsung-Yu; Chu, Yu-Ling

    2010-01-01

    This paper reports the results of a study which aimed to investigate how ubiquitous games influence English learning achievement and motivation through a context-aware ubiquitous learning environment. An English curriculum was conducted on a school campus by using a context-aware ubiquitous learning environment called the Handheld English Language…

  11. Network architecture test-beds as platforms for ubiquitous computing.

    PubMed

    Roscoe, Timothy

    2008-10-28

    Distributed systems research, and in particular ubiquitous computing, has traditionally assumed the Internet as a basic underlying communications substrate. Recently, however, the networking research community has come to question the fundamental design or 'architecture' of the Internet. This has been led by two observations: first, that the Internet as it stands is now almost impossible to evolve to support new functionality; and second, that modern applications of all kinds now use the Internet rather differently, and frequently implement their own 'overlay' networks above it to work around its perceived deficiencies. In this paper, I discuss recent academic projects to allow disruptive change to the Internet architecture, and also outline a radically different view of networking for ubiquitous computing that such proposals might facilitate.

  12. A system for ubiquitous health monitoring in the bedroom via a Bluetooth network and wireless LAN.

    PubMed

    Choi, J M; Choi, B H; Seo, J W; Sohn, R H; Ryu, M S; Yi, W; Park, K S

    2004-01-01

    Advances in information technology have enabled ubiquitous health monitoring at home, which is particularly useful for patients, who have to live alone. We have focused on the automatic and unobtrusive measurement of biomedical signals and activities of patients. We have constructed wireless communication networks in order to transfer data. The networks consist of Bluetooth and Wireless Local Area Network (WLAN). In this paper, we present the concept of a ubiquitous-Bedroom (u-Bedroom) which is a part of a ubiquitous-House (u-House) and we present our systems for ubiquitous health monitoring.

  13. A vision for ubiquitous sequencing

    PubMed Central

    Erlich, Yaniv

    2015-01-01

    Genomics has recently celebrated reaching the $1000 genome milestone, making affordable DNA sequencing a reality. With this goal successfully completed, the next goal of the sequencing revolution can be sequencing sensors—miniaturized sequencing devices that are manufactured for real-time applications and deployed in large quantities at low costs. The first part of this manuscript envisions applications that will benefit from moving the sequencers to the samples in a range of domains. In the second part, the manuscript outlines the critical barriers that need to be addressed in order to reach the goal of ubiquitous sequencing sensors. PMID:26430149

  14. Evidence for Bulk Ripplocations in Layered Solids

    NASA Astrophysics Data System (ADS)

    Gruber, Jacob; Lang, Andrew C.; Griggs, Justin; Taheri, Mitra L.; Tucker, Garritt J.; Barsoum, Michel W.

    2016-09-01

    Plastically anisotropic/layered solids are ubiquitous in nature and understanding how they deform is crucial in geology, nuclear engineering, microelectronics, among other fields. Recently, a new defect termed a ripplocation-best described as an atomic scale ripple-was proposed to explain deformation in two-dimensional solids. Herein, we leverage atomistic simulations of graphite to extend the ripplocation idea to bulk layered solids, and confirm that it is essentially a buckling phenomenon. In contrast to dislocations, bulk ripplocations have no Burgers vector and no polarity. In graphite, ripplocations are attracted to other ripplocations, both within the same, and on adjacent layers, the latter resulting in kink boundaries. Furthermore, we present transmission electron microscopy evidence consistent with the existence of bulk ripplocations in Ti3SiC2. Ripplocations are a topological imperative, as they allow atomic layers to glide relative to each other without breaking the in-plane bonds. A more complete understanding of their mechanics and behavior is critically important, and could profoundly influence our current understanding of how graphite, layered silicates, the MAX phases, and many other plastically anisotropic/layered solids, deform and accommodate strain.

  15. Ubiquitous Fast Propagating Intensity Disturbances in Solar Chromosphere

    NASA Technical Reports Server (NTRS)

    Kubo, M.; Katsukawa, Y.; Suematsu, Y.; Kano, R.; Bando, T.; Narukage, N.; Ishikawa, R.; Hara, H.; Giono, G.; Winebarger, A.; hide

    2016-01-01

    High cadence observations by the slit-jaw (SJ) optics system of the sounding rocket experiment "the Chromospheric Lyman Alpha SpectroPolarimeter (CLASP)" reveal ubiquitous intensity disturbances that recurrently propagate in either the chromosphere, transition region, or both at a speed much higher than the sound speed.

  16. Corneal Cross-Linking for the Treatment of Keratoconus in a Patient with Ipsilateral Myelinated Retinal Nerve Fiber Layer

    PubMed Central

    Leozappa, M.; Ciani, S.; Ferrari, T. Micelli

    2011-01-01

    Keratoconus associated with myelinated retinal nerve fibers is not frequent and the relationship between the two pathologies is difficult to explain, therefore studies and further investigation are required. The etiology of each condition may suggest the role of genetic factors. Follow-up is important to evaluate the progression of keratoconus and myelination. Here we describe the unusual coexistence of keratoconus and ipsilateral myelinated retinal nerve fiber layer and, for the first time, the corneal cross-linking treatment in this condition. PMID:21475609

  17. A Ubiquitous Blood Pressure Sensor Worn at the Ear

    NASA Astrophysics Data System (ADS)

    Koizumi, Hiroshi; Shimada, Junichi; Uenishi, Yuji; Tochikubo, Osamu

    2009-12-01

    Blood pressure (BP) measurement and BP control are important for the prevention of lifestyle diseases, especially hypertension, which can lead to more serious conditions, such as cardiac infarction and cerebral apoplexy. The purpose of our study is to develop a ubiquitous blood pressure sensor that is more comfortable and less disruptive of users' daily activities than conventional blood pressure sensors. Our developed sensor is worn at an ear orifice and measures blood pressure at the tragus. This paper describes the concept, configuration, and the optical and electronic details of the developed ear-worn blood pressure sensor and presents preliminary evaluation results. The developed sensor causes almost no discomfort and produces signals whose quality is high enough for detecting BP at an ear, making it suitable for ubiquitous usage.

  18. Development of HIHM (Home Integrated Health Monitor) for ubiquitous home healthcare.

    PubMed

    Kim, Jung Soo; Kim, Beom Oh; Park, Kwang Suk

    2007-01-01

    Home Integrated Health Monitor (HIHM) was developed for ubiquitous home healthcare. From quantitative analysis, we have elicited modal of chair. The HIHM could detect Electrocardiogram (ECG) and Photoplethysmography (PPG) non-intrusively. Also, it could estimate blood pressure (BP) non-intrusively, measure blood glucose and ear temperature. Detected signals and information were transmitted to home gateway and home server through Zigbee communication technology. Home server carried them to Healthcare Center, and specialists such as medical doctors could monitor by Internet. There was also feedback system. This device has a potential to study about ubiquitous home healthcare.

  19. Linking Dynamics of the Near-surface Flow to Deeper Boundary Layer Forcing in the Nocturnal Boundary Layer

    DTIC Science & Technology

    2012-06-01

    Kaimal and Finnigan (1994), modified) Figure 2.2 illustrates the evolution from unstable CBL to a nocturnal Stable Bound- ary Layer ( SBL ) in the absence...mixed layer acts as a cap for the SBL . The SBL persists through the night until sunrise when surface heating resumes and a new unstable layer begins...to form at the surface, gradually returning to a CBL. 7 2.2.1 Dynamics of the stable boundary layer Because the SBL is stably stratified, buoyancy

  20. Method Producing an SNS Superconducting Junction with Weak Link Barrier

    NASA Technical Reports Server (NTRS)

    Hunt, Brian D. (Inventor)

    1999-01-01

    A method of producing a high temperature superconductor Josephson element and an improved SNS weak link barrier element is provided. A YBaCuO superconducting electrode film is deposited on a substrate at a temperature of approximately 800 C. A weak link barrier layer of a nonsuperconducting film of N-YBaCuO is deposited over the electrode at a temperature range of 520 C. to 540 C. at a lower deposition rate. Subsequently a superconducting counter-electrode film layer of YBaCuO is deposited over the weak link barrier layer at approximately 800 C. The weak link barrier layer has a thickness of approximately 50 A and the SNS element can be constructed to provide an edge geometry junction.

  1. Ubiquitous Learning Ecologies for a Critical Cyber-Citizenship

    ERIC Educational Resources Information Center

    Díez-Gutiérrez, Enrique; Díaz-Nafría, José-María

    2018-01-01

    The aim of this research is to identify and analyse the ubiquitous learning acquired through blending education settings devoted to the "lifelong training of trainers" and how these contribute to the development of a conscious, critic and engaged citizenship. Through active exploration of the learning process, the study analyses the…

  2. Conjoint Analysis for Mobile Devices for Ubiquitous Learning in Higher Education: The Korean Case

    ERIC Educational Resources Information Center

    Lee, Hyeongjik

    2013-01-01

    Despite the increasing importance of mobile devices in education, the essential features of these devices for ubiquitous learning have not been empirically addressed. This study empirically investigated the necessary conditions for using mobile devices as an educational tool for ubiquitous learning in higher education by a conjoint method. The…

  3. An Expert System-based Context-Aware Ubiquitous Learning Approach for Conducting Science Learning Activities

    ERIC Educational Resources Information Center

    Wu, Po-Han; Hwang, Gwo-Jen; Tsai, Wen-Hung

    2013-01-01

    Context-aware ubiquitous learning has been recognized as being a promising approach that enables students to interact with real-world learning targets with supports from the digital world. Several researchers have indicated the importance of providing learning guidance or hints to individual students during the context-aware ubiquitous learning…

  4. Link prediction in multiplex online social networks.

    PubMed

    Jalili, Mahdi; Orouskhani, Yasin; Asgari, Milad; Alipourfard, Nazanin; Perc, Matjaž

    2017-02-01

    Online social networks play a major role in modern societies, and they have shaped the way social relationships evolve. Link prediction in social networks has many potential applications such as recommending new items to users, friendship suggestion and discovering spurious connections. Many real social networks evolve the connections in multiple layers (e.g. multiple social networking platforms). In this article, we study the link prediction problem in multiplex networks. As an example, we consider a multiplex network of Twitter (as a microblogging service) and Foursquare (as a location-based social network). We consider social networks of the same users in these two platforms and develop a meta-path-based algorithm for predicting the links. The connectivity information of the two layers is used to predict the links in Foursquare network. Three classical classifiers (naive Bayes, support vector machines (SVM) and K-nearest neighbour) are used for the classification task. Although the networks are not highly correlated in the layers, our experiments show that including the cross-layer information significantly improves the prediction performance. The SVM classifier results in the best performance with an average accuracy of 89%.

  5. Link prediction in multiplex online social networks

    NASA Astrophysics Data System (ADS)

    Jalili, Mahdi; Orouskhani, Yasin; Asgari, Milad; Alipourfard, Nazanin; Perc, Matjaž

    2017-02-01

    Online social networks play a major role in modern societies, and they have shaped the way social relationships evolve. Link prediction in social networks has many potential applications such as recommending new items to users, friendship suggestion and discovering spurious connections. Many real social networks evolve the connections in multiple layers (e.g. multiple social networking platforms). In this article, we study the link prediction problem in multiplex networks. As an example, we consider a multiplex network of Twitter (as a microblogging service) and Foursquare (as a location-based social network). We consider social networks of the same users in these two platforms and develop a meta-path-based algorithm for predicting the links. The connectivity information of the two layers is used to predict the links in Foursquare network. Three classical classifiers (naive Bayes, support vector machines (SVM) and K-nearest neighbour) are used for the classification task. Although the networks are not highly correlated in the layers, our experiments show that including the cross-layer information significantly improves the prediction performance. The SVM classifier results in the best performance with an average accuracy of 89%.

  6. Ubiquitous Mobile Technologies and the Transformation of Schooling

    ERIC Educational Resources Information Center

    Bjerede, Marie; Atkins, Kristin; Dede, Chris

    2010-01-01

    This article explores how the Internet and mobile broadband technologies that are transforming the work of business professionals may be applied to the work of teachers and students in K-20 schooling, with similarly transformative outcomes. First, they discuss the ways in which ubiquitous mobile technologies are changing 21st century business.…

  7. Study on the context-aware middleware for ubiquitous greenhouses using wireless sensor networks.

    PubMed

    Hwang, Jeonghwang; Yoe, Hyun

    2011-01-01

    Wireless Sensor Network (WSN) technology is one of the important technologies to implement the ubiquitous society, and it could increase productivity of agricultural and livestock products, and secure transparency of distribution channels if such a WSN technology were successfully applied to the agricultural sector. Middleware, which can connect WSN hardware, applications, and enterprise systems, is required to construct ubiquitous agriculture environment combining WSN technology with agricultural sector applications, but there have been insufficient studies in the field of WSN middleware in the agricultural environment, compared to other industries. This paper proposes a context-aware middleware to efficiently process data collected from ubiquitous greenhouses by applying WSN technology and used to implement combined services through organic connectivity of data. The proposed middleware abstracts heterogeneous sensor nodes to integrate different forms of data, and provides intelligent context-aware, event service, and filtering functions to maximize operability and scalability of the middleware. To evaluate the performance of the middleware, an integrated management system for ubiquitous greenhouses was implemented by applying the proposed middleware to an existing greenhouse, and it was tested by measuring the level of load through CPU usage and the response time for users' requests when the system is working.

  8. A novel multilayer model for missing link prediction and future link forecasting in dynamic complex networks

    NASA Astrophysics Data System (ADS)

    Yasami, Yasser; Safaei, Farshad

    2018-02-01

    The traditional complex network theory is particularly focused on network models in which all network constituents are dealt with equivalently, while fail to consider the supplementary information related to the dynamic properties of the network interactions. This is a main constraint leading to incorrect descriptions of some real-world phenomena or incomplete capturing the details of certain real-life problems. To cope with the problem, this paper addresses the multilayer aspects of dynamic complex networks by analyzing the properties of intrinsically multilayered co-authorship networks, DBLP and Astro Physics, and presenting a novel multilayer model of dynamic complex networks. The model examines the layers evolution (layers birth/death process and lifetime) throughout the network evolution. Particularly, this paper models the evolution of each node's membership in different layers by an Infinite Factorial Hidden Markov Model considering feature cascade, and thereby formulates the link generation process for intra-layer and inter-layer links. Although adjacency matrixes are useful to describe the traditional single-layer networks, such a representation is not sufficient to describe and analyze the multilayer dynamic networks. This paper also extends a generalized mathematical infrastructure to address the problems issued by multilayer complex networks. The model inference is performed using some Markov Chain Monte Carlo sampling strategies, given synthetic and real complex networks data. Experimental results indicate a tremendous improvement in the performance of the proposed multilayer model in terms of sensitivity, specificity, positive and negative predictive values, positive and negative likelihood ratios, F1-score, Matthews correlation coefficient, and accuracy for two important applications of missing link prediction and future link forecasting. The experimental results also indicate the strong predictivepower of the proposed model for the application of

  9. A large and ubiquitous source of atmospheric formic acid

    NASA Astrophysics Data System (ADS)

    Millet, D. B.; Baasandorj, M.; Farmer, D. K.; Thornton, J. A.; Baumann, K.; Brophy, P.; Chaliyakunnel, S.; de Gouw, J. A.; Graus, M.; Hu, L.; Koss, A.; Lee, B. H.; Lopez-Hilfiker, F. D.; Neuman, J. A.; Paulot, F.; Peischl, J.; Pollack, I. B.; Ryerson, T. B.; Warneke, C.; Williams, B. J.; Xu, J.

    2015-06-01

    Formic acid (HCOOH) is one of the most abundant acids in the atmosphere, with an important influence on precipitation chemistry and acidity. Here we employ a chemical transport model (GEOS-Chem CTM) to interpret recent airborne and ground-based measurements over the US Southeast in terms of the constraints they provide on HCOOH sources and sinks. Summertime boundary layer concentrations average several parts-per-billion, 2-3× larger than can be explained based on known production and loss pathways. This indicates one or more large missing HCOOH sources, and suggests either a key gap in current understanding of hydrocarbon oxidation or a large, unidentified, direct flux of HCOOH. Model-measurement comparisons implicate biogenic sources (e.g., isoprene oxidation) as the predominant HCOOH source. Resolving the unexplained boundary layer concentrations based (i) solely on isoprene oxidation would require a 3× increase in the model HCOOH yield, or (ii) solely on direct HCOOH emissions would require approximately a 25× increase in its biogenic flux. However, neither of these can explain the high HCOOH amounts seen in anthropogenic air masses and in the free troposphere. The overall indication is of a large biogenic source combined with ubiquitous chemical production of HCOOH across a range of precursors. Laboratory work is needed to better quantify the rates and mechanisms of carboxylic acid production from isoprene and other prevalent organics. Stabilized Criegee intermediates (SCIs) provide a large model source of HCOOH, while acetaldehyde tautomerization accounts for ~ 15% of the simulated global burden. Because carboxylic acids also react with SCIs and catalyze the reverse tautomerization reaction, HCOOH buffers against its own production by both of these pathways. Based on recent laboratory results, reaction between CH3O2 and OH could provide a major source of atmospheric HCOOH; however, including this chemistry degrades the model simulation of CH3OOH and NOx

  10. Ubiquitous Computing Services Discovery and Execution Using a Novel Intelligent Web Services Algorithm

    PubMed Central

    Choi, Okkyung; Han, SangYong

    2007-01-01

    Ubiquitous Computing makes it possible to determine in real time the location and situations of service requesters in a web service environment as it enables access to computers at any time and in any place. Though research on various aspects of ubiquitous commerce is progressing at enterprises and research centers, both domestically and overseas, analysis of a customer's personal preferences based on semantic web and rule based services using semantics is not currently being conducted. This paper proposes a Ubiquitous Computing Services System that enables a rule based search as well as semantics based search to support the fact that the electronic space and the physical space can be combined into one and the real time search for web services and the construction of efficient web services thus become possible.

  11. Distributed user interfaces for clinical ubiquitous computing applications.

    PubMed

    Bång, Magnus; Larsson, Anders; Berglund, Erik; Eriksson, Henrik

    2005-08-01

    Ubiquitous computing with multiple interaction devices requires new interface models that support user-specific modifications to applications and facilitate the fast development of active workspaces. We have developed NOSTOS, a computer-augmented work environment for clinical personnel to explore new user interface paradigms for ubiquitous computing. NOSTOS uses several devices such as digital pens, an active desk, and walk-up displays that allow the system to track documents and activities in the workplace. We present the distributed user interface (DUI) model that allows standalone applications to distribute their user interface components to several devices dynamically at run-time. This mechanism permit clinicians to develop their own user interfaces and forms to clinical information systems to match their specific needs. We discuss the underlying technical concepts of DUIs and show how service discovery, component distribution, events and layout management are dealt with in the NOSTOS system. Our results suggest that DUIs--and similar network-based user interfaces--will be a prerequisite of future mobile user interfaces and essential to develop clinical multi-device environments.

  12. Di-isodityrosine is the intermolecular cross-link of isodityrosine-rich extensin analogs cross-linked in vitro.

    PubMed

    Held, Michael A; Tan, Li; Kamyab, Abdolreza; Hare, Michael; Shpak, Elena; Kieliszewski, Marcia J

    2004-12-31

    Extensins are cell wall hydroxyproline-rich glycoproteins that form covalent networks putatively involving tyrosyl and lysyl residues in cross-links catalyzed by one or more extensin peroxidases. The precise cross-links remain to be chemically identified both as network components in muro and as enzymic products generated in vitro with native extensin monomers as substrates. However, some extensin monomers contain variations within their putative cross-linking motifs that complicate cross-link identification. Other simpler extensins are recalcitrant to isolation including the ubiquitous P3-type extensin whose major repetitive motif, Hyp)(4)-Ser-Hyp-Ser-(Hyp)(4)-Tyr-Tyr-Tyr-Lys, is of particular interest, not least because its Tyr-Tyr-Tyr intramolecular isodityrosine cross-link motifs are also putative candidates for further intermolecular cross-linking to form di-isodityrosine. Therefore, we designed a set of extensin analogs encoding tandem repeats of the P3 motif, including Tyr --> Phe and Lys --> Leu variations. Expression of these P3 analogs in Nicotiana tabacum cells yielded glycoproteins with virtually all Pro residues hydroxylated and subsequently arabinosylated and with likely galactosylated Ser residues. This was consistent with earlier analyses of P3 glycopeptides isolated from cell wall digests and the predictions of the Hyp contiguity hypothesis. The tyrosine-rich P3 analogs also contained isodityrosine, formed in vivo. Significantly, these isodityrosine-containing analogs were further cross-linked in vitro by an extensin peroxidase to form the tetra-tyrosine intermolecular cross-link amino acid di-isodityrosine. This is the first identification of an inter-molecular cross-link amino acid in an extensin module and corroborates earlier suggestions that di-isodityrosine represents one mechanism for cross-linking extensins in muro.

  13. Development of a Ubiquitous Learning Platform Based on a Real-Time Help-Seeking Mechanism

    ERIC Educational Resources Information Center

    Hwang, Gwo-Jen; Wu, Chih-Hsiang; Tseng, Judy C. R.; Huang, Iwen

    2011-01-01

    The popularity of mobile devices has encouraged the advance of ubiquitous learning, in which students are situated in a real-world learning environment with support from the digital world via the use of mobile, wireless communications, or even sensing technologies. Most of the ubiquitous learning systems are implemented with high-cost sensing…

  14. Logic-centered architecture for ubiquitous health monitoring.

    PubMed

    Lewandowski, Jacek; Arochena, Hisbel E; Naguib, Raouf N G; Chao, Kuo-Ming; Garcia-Perez, Alexeis

    2014-09-01

    One of the key points to maintain and boost research and development in the area of smart wearable systems (SWS) is the development of integrated architectures for intelligent services, as well as wearable systems and devices for health and wellness management. This paper presents such a generic architecture for multiparametric, intelligent and ubiquitous wireless sensing platforms. It is a transparent, smartphone-based sensing framework with customizable wireless interfaces and plug'n'play capability to easily interconnect third party sensor devices. It caters to wireless body, personal, and near-me area networks. A pivotal part of the platform is the integrated inference engine/runtime environment that allows the mobile device to serve as a user-adaptable personal health assistant. The novelty of this system lays in a rapid visual development and remote deployment model. The complementary visual Inference Engine Editor that comes with the package enables artificial intelligence specialists, alongside with medical experts, to build data processing models by assembling different components and instantly deploying them (remotely) on patient mobile devices. In this paper, the new logic-centered software architecture for ubiquitous health monitoring applications is described, followed by a discussion as to how it helps to shift focus from software and hardware development, to medical and health process-centered design of new SWS applications.

  15. Mobile Computing and Ubiquitous Networking: Concepts, Technologies and Challenges.

    ERIC Educational Resources Information Center

    Pierre, Samuel

    2001-01-01

    Analyzes concepts, technologies and challenges related to mobile computing and networking. Defines basic concepts of cellular systems. Describes the evolution of wireless technologies that constitute the foundations of mobile computing and ubiquitous networking. Presents characterization and issues of mobile computing. Analyzes economical and…

  16. RACORO Extended-Term Aircraft Observations of Boundary-Layer Clouds

    NASA Technical Reports Server (NTRS)

    Vogelmann, Andrew M.; McFarquhar, Greg M.; Ogren, John A.; Turner, David D.; Comstock, Jennifer M.; Feingold, Graham; Long, Charles N.; Jonsson, Haflidi H.; Bucholtz, Anthony; Collins, Don R.; hide

    2012-01-01

    Small boundary-layer clouds are ubiquitous over many parts of the globe and strongly influence the Earths radiative energy balance. However, our understanding of these clouds is insufficient to solve pressing scientific problems. For example, cloud feedback represents the largest uncertainty amongst all climate feedbacks in general circulation models (GCM). Several issues complicate understanding boundary-layer clouds and simulating them in GCMs. The high spatial variability of boundary-layer clouds poses an enormous computational challenge, since their horizontal dimensions and internal variability occur at spatial scales much finer than the computational grids used in GCMs. Aerosol-cloud interactions further complicate boundary-layer cloud measurement and simulation. Additionally, aerosols influence processes such as precipitation and cloud lifetime. An added complication is that at small scales (order meters to 10s of meters) distinguishing cloud from aerosol is increasingly difficult, due to the effects of aerosol humidification, cloud fragments and photon scattering between clouds.

  17. [Facing the challenges of ubiquitous computing in the health care sector].

    PubMed

    Georgieff, Peter; Friedewald, Michael

    2010-01-01

    The steady progress of microelectronics, communications and information technology will enable the realisation of the vision for "ubiquitous computing" where the Internet extends into the real world embracing everyday objects. The necessary technical basis is already in place. Due to their diminishing size, constantly falling price and declining energy consumption, processors, communications modules and sensors are being increasingly integrated into everyday objects today. This development is opening up huge opportunities for both the economy and individuals. In the present paper we discuss possible applications, but also technical, social and economic barriers to a wide-spread use of ubiquitous computing in the health care sector. .

  18. Ubiquitous Complete in a Web 2.0 World

    ERIC Educational Resources Information Center

    Bull, Glen; Ferster, Bill

    2006-01-01

    In the third wave of computing, people will interact with multiple computers in multiple ways in every setting. The value of ubiquitous computing is enhanced and reinforced by another trend: the transition to a Web 2.0 world. In a Web 2.0 world, applications and data reside on the Web itself. Schools are not yet approaching a ratio of one…

  19. Design requirements for ubiquitous computing environments for healthcare professionals.

    PubMed

    Bång, Magnus; Larsson, Anders; Eriksson, Henrik

    2004-01-01

    Ubiquitous computing environments can support clinical administrative routines in new ways. The aim of such computing approaches is to enhance routine physical work, thus it is important to identify specific design requirements. We studied healthcare professionals in an emergency room and developed the computer-augmented environment NOSTOS to support teamwork in that setting. NOSTOS uses digital pens and paper-based media as the primary input interface for data capture and as a means of controlling the system. NOSTOS also includes a digital desk, walk-up displays, and sensor technology that allow the system to track documents and activities in the workplace. We propose a set of requirements and discuss the value of tangible user interfaces for healthcare personnel. Our results suggest that the key requirements are flexibility in terms of system usage and seamless integration between digital and physical components. We also discuss how ubiquitous computing approaches like NOSTOS can be beneficial in the medical workplace.

  20. Empowering Pre-Service Teachers to Produce Ubiquitous Flipped Classes

    ERIC Educational Resources Information Center

    García-Sánchez, Soraya; Santos-Espino, Jose Miguel

    2017-01-01

    This work focuses on technological and educational outcomes that resulted from the production of foreign language educational videos by 90 pre-service instructors enrolled in an official Master's Degree in Secondary Education programme. This teaching practice, conducted during two consecutive years, was set in a ubiquitous learning environment…

  1. A comprehensive Reputation mechanism for ubiquitous healthcare environment exploiting cloud model.

    PubMed

    Athanasiou, Georgia; Lymberopoulos, Dimitrios

    2016-08-01

    Absence of trust foundations may outweigh benefits of ubiquitous and personalized mental healthcare supervision provided within a Ubiquitous Healthcare environment (UH). Trust is composed by patient's Personal Interaction Experience (PIE) and social entourage accumulated PIE, i.e. Reputation (R). In this paper, a cloud-based Reputation mechanism is proposed. Since PIE is the elementary trust information source, also an Updating mechanism of PIE, is introduced, in this paper. Cloud materialization of combined mechanisms provides adaptability to UH Providers' dynamic behavior, facilitates detection of milking behaviors and complex malicious attacks while meets the challenge of limited accuracy in case of data sparseness. The effectiveness of the proposed mechanisms is verified via simulation in MATLAB.

  2. Characterization of Instructor and Student Use of Ubiquitous Presenter, a Presentation System Enabling Spontaneity and Digital Archiving

    NASA Astrophysics Data System (ADS)

    Price, Edward; Malani, Roshni; Simon, Beth

    2007-01-01

    Ubiquitous Presenter (UP) is a digital presentation system that allows an instructor with a Tablet PC to spontaneously modify prepared slides, while automatically archiving the inked slides on the web. For two introductory physics classes, we examine the types of slides instructors prepare and the ways in which they add ink to the slides. Modes of usage include: using ink to explicitly link multiple representations; making prepared figures dynamic by animating them with ink; and preparing slides with sparse text or figures, then adding extensive annotations during class. In addition, through an analysis of surveys and of web server logs, we examine student reaction to the system, as well as how often and in what ways students' utilize archived material. In general, students find the system valuable and frequently review the presentations online.

  3. Study: Ozone Layer's Future Linked Strongly to Changes in Climate

    Science.gov Websites

    balloon to measure of the vertical profile of the ozone layer. NOAA scientists launch an ozonesonde via balloon to measure of the vertical profile of the ozone layer. NOAA releases ozonesondes at eight sites worldwide, including the Amundsen-Scott South Pole Station. It also uses satellite and ground-based systems

  4. The Tropopause Inversion Layer in Baroclinic Life Cycle Experiments

    NASA Astrophysics Data System (ADS)

    Wirth, Volkmar; Erler, Andre

    2010-05-01

    The Tropopause Inversion Layer (TIL) is a region of enhanced static stability just above the thermal tropopause. It is a ubiquitous feature in midlatitudes and is well characterized by observations; however, it still lacks a full theoretical explanation. The current study uses adiabatic baroclinic life-cycle experiments in order to investigate dynamical mechanisms that lead to the formation of a TIL. Consistent with earlier results, no TIL is found above cyclonic anomalies, while a pronounced TIL is found above anticyclonic anomalies early during the life cycle. Interestingly, regarding tropopause based global mean profiles, a TIL can be seen only much later during the life cycle, at a time when wave breaking starts to occur. There is a significant rise of the thermal tropopause, which is spatially and temporally correlated with TIL formation. In contrast, the dynamical tropopause does not rise significantly and does not exhibit a TIL in the global mean. The results of these experiments are interpreted using earlier results about the nonlinear dependence of the TIL amplitude on the scale of the tropopause anomaly. The analysis suggests that the TIL (as a global mean feature) is linked to a strongly asymmetric distribution of cyclonic and anticyclonic anomalies, which occurs after the wave breaking event.

  5. Ubiquitous learning model using interactive internet messenger group (IIMG) to improve engagement and behavior for smart campus

    NASA Astrophysics Data System (ADS)

    Umam, K.; Mardi, S. N. S.; Hariadi, M.

    2017-01-01

    The recent popularity of internet messenger based smartphone technologies has motivated some university lecturers to use them for educational activities. These technologies have enormous potential to enhance the teaching and ubiquitous learning experience for smart campus development. However, the design ubiquitous learning model using interactive internet messenger group (IIMG) and empirical evidence that would favor a broad application of mobile and ubiquitous learning in smart campus settings to improve engagement and behavior is still limited. In addition, the expectation that mobile learning could improve engagement and behavior on smart campus cannot be confirmed because the majority of the reviewed studies followed instructions paradigms. This article aims to present ubiquitous learning model design and showing learners’ experiences in improved engagement and behavior using IIMG for learner-learner and learner-lecturer interactions. The method applied in this paper includes design process and quantitative analysis techniques, with the purpose of identifying scenarios of ubiquitous learning and realize the impressions of learners and lecturers about engagement and behavior aspect, and its contribution to learning.

  6. Using Palm Technology in Participatory Simulations of Complex Systems: A New Take on Ubiquitous and Accessible Mobile Computing

    NASA Astrophysics Data System (ADS)

    Klopfer, Eric; Yoon, Susan; Perry, Judy

    2005-09-01

    This paper reports on teachers' perceptions of the educational affordances of a handheld application called Participatory Simulations. It presents evidence from five cases representing each of the populations who work with these computational tools. Evidence across multiple data sources yield similar results to previous research evaluations of handheld activities with respect to enhancing motivation, engagement and self-directed learning. Three additional themes are discussed that provide insight into understanding curricular applicability of Participatory Simulations that suggest a new take on ubiquitous and accessible mobile computing. These themes generally point to the multiple layers of social and cognitive flexibility intrinsic to their design: ease of adaptation to subject-matter content knowledge and curricular integration; facility in attending to teacher-individualized goals; and encouraging the adoption of learner-centered strategies.

  7. From Online to Ubiquitous Cities: The Technical Transformation of Virtual Communities

    NASA Astrophysics Data System (ADS)

    Anthopoulos, Leonidas; Fitsilis, Panos

    Various digital city projects, from the online cases (e.g. the America on Line) to the ubiquitous cities of South Korea, have achieved in creating technically 'physical' areas for the virtual communities, which share knowledge of common interest. Moreover, digital cities can succeed in simplifying citizen access to public information and services. Early digital cities deliver 'smart' and social services to citizens even with no digital skills, closing digital divide and establishing digital areas of trust in local communities. This paper presents the evolution of the digital cities, from the web to the ubiquitous architecture. It uses the latest digital city architecture and the current conditions of the digital city of Trikala (Greece), in order to present the evolution procedure of a digital city.

  8. Twenty-First Century Learning: Communities, Interaction and Ubiquitous Computing

    ERIC Educational Resources Information Center

    Leh, Amy S.C.; Kouba, Barbara; Davis, Dirk

    2005-01-01

    Advanced technology makes 21st century learning, communities and interactions unique and leads people to an era of ubiquitous computing. The purpose of this article is to contribute to the discussion of learning in the 21st century. The paper will review literature on learning community, community learning, interaction, 21st century learning and…

  9. Ubiquitous testing using tablets: its impact on medical student perceptions of and engagement in learning.

    PubMed

    Kim, Kyong-Jee; Hwang, Jee-Young

    2016-03-01

    Ubiquitous testing has the potential to affect medical education by enhancing the authenticity of the assessment using multimedia items. This study explored medical students' experience with ubiquitous testing and its impact on student learning. A cohort (n=48) of third-year students at a medical school in South Korea participated in this study. The students were divided into two groups and were given different versions of 10 content-matched items: one in text version (the text group) and the other in multimedia version (the multimedia group). Multimedia items were delivered using tablets. Item response analyses were performed to compare item characteristics between the two versions. Additionally, focus group interviews were held to investigate the students' experiences of ubiquitous testing. The mean test score was significantly higher in the text group. Item difficulty and discrimination did not differ between text and multimedia items. The participants generally showed positive responses on ubiquitous testing. Still, they felt that the lectures that they had taken in preclinical years did not prepare them enough for this type of assessment and clinical encounters during clerkships were more helpful. To be better prepared, the participants felt that they needed to engage more actively in learning in clinical clerkships and have more access to multimedia learning resources. Ubiquitous testing can positively affect student learning by reinforcing the importance of being able to understand and apply knowledge in clinical contexts, which drives students to engage more actively in learning in clinical settings.

  10. A novel method of measuring leaf epidermis and mesophyll stiffness shows the ubiquitous nature of the sandwich structure of leaf laminas in broad-leaved angiosperm species

    PubMed Central

    Onoda, Yusuke; Schieving, Feike; Anten, Niels P. R.

    2015-01-01

    Plant leaves commonly exhibit a thin, flat structure that facilitates a high light interception per unit mass, but may increase risks of mechanical failure when subjected to gravity, wind and herbivory as well as other stresses. Leaf laminas are composed of thin epidermis layers and thicker intervening mesophyll layers, which resemble a composite material, i.e. sandwich structure, used in engineering constructions (e.g. airplane wings) where high bending stiffness with minimum weight is important. Yet, to what extent leaf laminas are mechanically designed and behave as a sandwich structure remains unclear. To resolve this issue, we developed and applied a novel method to estimate stiffness of epidermis- and mesophyll layers without separating the layers. Across a phylogenetically diverse range of 36 angiosperm species, the estimated Young’s moduli (a measure of stiffness) of mesophyll layers were much lower than those of the epidermis layers, indicating that leaf laminas behaved similarly to efficient sandwich structures. The stiffness of epidermis layers was higher in evergreen species than in deciduous species, and strongly associated with cuticle thickness. The ubiquitous nature of sandwich structures in leaves across studied species suggests that the sandwich structure has evolutionary advantages as it enables leaves to be simultaneously thin and flat, efficiently capturing light and maintaining mechanical stability under various stresses. PMID:25675956

  11. A novel method of measuring leaf epidermis and mesophyll stiffness shows the ubiquitous nature of the sandwich structure of leaf laminas in broad-leaved angiosperm species.

    PubMed

    Onoda, Yusuke; Schieving, Feike; Anten, Niels P R

    2015-05-01

    Plant leaves commonly exhibit a thin, flat structure that facilitates a high light interception per unit mass, but may increase risks of mechanical failure when subjected to gravity, wind and herbivory as well as other stresses. Leaf laminas are composed of thin epidermis layers and thicker intervening mesophyll layers, which resemble a composite material, i.e. sandwich structure, used in engineering constructions (e.g. airplane wings) where high bending stiffness with minimum weight is important. Yet, to what extent leaf laminas are mechanically designed and behave as a sandwich structure remains unclear. To resolve this issue, we developed and applied a novel method to estimate stiffness of epidermis- and mesophyll layers without separating the layers. Across a phylogenetically diverse range of 36 angiosperm species, the estimated Young's moduli (a measure of stiffness) of mesophyll layers were much lower than those of the epidermis layers, indicating that leaf laminas behaved similarly to efficient sandwich structures. The stiffness of epidermis layers was higher in evergreen species than in deciduous species, and strongly associated with cuticle thickness. The ubiquitous nature of sandwich structures in leaves across studied species suggests that the sandwich structure has evolutionary advantages as it enables leaves to be simultaneously thin and flat, efficiently capturing light and maintaining mechanical stability under various stresses. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  12. Unified Stress Tensor of the Hydration Water Layer

    NASA Astrophysics Data System (ADS)

    Kim, Bongsu; Kim, QHwan; Kwon, Soyoung; An, Sangmin; Lee, Kunyoung; Lee, Manhee; Jhe, Wonho

    2013-12-01

    We present the general stress tensor of the ubiquitous hydration water layer (HWL), based on the empirical hydration force, by combining the elasticity and hydrodynamics theories. The tapping and shear component of the tensor describe the elastic and damping properties of the HWL, respectively, in good agreement with experiments. In particular, a unified understanding of HWL dynamics provides the otherwise unavailable intrinsic parameters of the HWL, which offer additional but unexplored aspects to the supercooled liquidity of the confined HWL. Our results may allow deeper insight on systems where the HWL is critical.

  13. Unified stress tensor of the hydration water layer.

    PubMed

    Kim, Bongsu; Kim, Qhwan; Kwon, Soyoung; An, Sangmin; Lee, Kunyoung; Lee, Manhee; Jhe, Wonho

    2013-12-13

    We present the general stress tensor of the ubiquitous hydration water layer (HWL), based on the empirical hydration force, by combining the elasticity and hydrodynamics theories. The tapping and shear component of the tensor describe the elastic and damping properties of the HWL, respectively, in good agreement with experiments. In particular, a unified understanding of HWL dynamics provides the otherwise unavailable intrinsic parameters of the HWL, which offer additional but unexplored aspects to the supercooled liquidity of the confined HWL. Our results may allow deeper insight on systems where the HWL is critical.

  14. Temporal identity in axonal target layer recognition.

    PubMed

    Petrovic, Milan; Hummel, Thomas

    2008-12-11

    The segregation of axon and dendrite projections into distinct synaptic layers is a fundamental principle of nervous system organization and the structural basis for information processing in the brain. Layer-specific recognition molecules that allow projecting neurons to stabilize transient contacts and initiate synaptogenesis have been identified. However, most of the neuronal cell-surface molecules critical for layer organization are expressed broadly in the developing nervous system, raising the question of how these so-called permissive adhesion molecules support synaptic specificity. Here we show that the temporal expression dynamics of the zinc-finger protein sequoia is the major determinant of Drosophila photoreceptor connectivity into distinct synaptic layers. Neighbouring R8 and R7 photoreceptors show consecutive peaks of elevated sequoia expression, which correspond to their sequential target-layer innervation. Loss of sequoia in R7 leads to a projection switch into the R8 recipient layer, whereas a prolonged expression in R8 induces a redirection of their axons into the R7 layer. The sequoia-induced axon targeting is mediated through the ubiquitously expressed Cadherin-N cell adhesion molecule. Our data support a model in which recognition specificity during synaptic layer formation is generated through a temporally restricted axonal competence to respond to broadly expressed adhesion molecules. Because developing neurons innervating the same target area often project in a distinct, birth-order-dependent sequence, temporal identity seems to contain crucial information in generating not only cell type diversity during neuronal division but also connection diversity of projecting neurons.

  15. Ubiquitous Performance-Support System as Mindtool: A Case Study of Instructional Decision Making and Learning Assistant

    ERIC Educational Resources Information Center

    Peng, Hsinyi; Chuang, Po-Ya; Hwang, Gwo-Jen; Chu, Hui-Chun; Wu, Ting-Ting; Huang, Shu-Xian

    2009-01-01

    Researchers have conducted various studies on applying wireless communication and ubiquitous computing technologies to education, so that the technologies can provide learners and educators with more active and adaptive support. This study proposes a Ubiquitous Performance-support System (UPSS) that can facilitate the seamless use of powerful new…

  16. The CCSDS Next Generation Space Data Link Protocol (NGSLP)

    NASA Technical Reports Server (NTRS)

    Kazz, Greg J.; Greenberg, Edward

    2014-01-01

    next leap in performance for space link communications. Field Programmable Gate Arrays (FPGAs) provide the capability to incorporate high performance forward error correcting codes implemented within software transponders providing improved performance in data transfer, ranging, link security, and time correlation. Given these synergistic technological breakthroughs, the time has come to take advantage of them in applying them to both on going (e.g., command, telemetry) and emerging (e.g., space link security, optical communication) space link applications. However one of the constraining factors within the Data Link Layer in realizing these performance gains is the lack of a generic transfer frame format and common supporting services amongst the existing CCSDS link layer protocols. Currently each of the four CCSDS link layer protocols (TM, TC, AOS, and Proximity-1) have unique formats and services which prohibits their reuse across the totality of all space link applications of CCSDS member space agencies. For example, Mars missions. These missions implement their proximity data link layer using the Proximity-1 frame format and the services it supports but is still required to support the direct from Earth (TC) protocols and the Direct To Earth (AOS/TM) protocols. The prime purpose of this paper, is to describe a new general purpose CCSDS Data Link layer protocol, the NGSLP that will provide the required services along with a common transfer frame format for all the CCSDS space links (ground to/from space and space to space links) targeted for emerging missions after a CCSDS agency-wide coordinated date. This paper will also describe related options that can be included for the Coding and Synchronization sub-layer of the Data Link layer to extend the capacities of the link and additionally provide an independence of the transfer frame sub-layer from the coding sublayer. This feature will provide missions the option of running either the currently performed

  17. Foveomacular schisis in juvenile X-linked retinoschisis: an optical coherence tomography study.

    PubMed

    Yu, Jia; Ni, Yingqin; Keane, Pearse A; Jiang, Chunhui; Wang, Wenji; Xu, Gezhi

    2010-06-01

    To explore the structural features of juvenile X-linked retinoschisis using spectral-domain optical coherence tomography (OCT). Retrospective, observational cross-sectional study. Eighteen male patients (34 eyes) who were diagnosed with juvenile X-linked retinoschisis at the Eye & ENT Hospital of Fudan University over an 18-month period were included. Their OCT images, which were obtained using spectral-domain OCT (Cirrus HD-OCT; Carl Zeiss Meditec), were analyzed. The anatomic location of the schisis cavity in juvenile X-linked retinoschisis was characterized by direct inspection of OCT images. On OCT, the schisis cavity was visible at the fovea in all 34 eyes, and it was associated with increased retinal thickness. Schisis was present at the retinal nerve fiber layer in 4 eyes, at the inner nuclear layer in 29 eyes, and at the outer nuclear layer/outer plexiform layer in 22 eyes. In most cases, widespread foveomacular schisis was detected using OCT; however, in 9 eyes (6 patients), the schisis was confined to the fovea. Schisis of the inner nuclear layer and outer nuclear layer/outer plexiform layer almost always involved the foveal center, but retinal nerve fiber layer schisis was seen only in the parafoveal area. Despite conventional wisdom, in patients with X-linked retinoschisis, the schisis cavity can occur in a number of different layers of the neurosensory retina (retinal nerve fiber layer, inner nuclear layer, and outer nuclear layer/outer plexiform layer). In addition, different forms of schisis may affect different locations in the macula (foveal vs parafoveal), and, in most eyes, the schisis involves the entire foveomacular region. Copyright 2010 Elsevier Inc. All rights reserved.

  18. Ubiquitous testing using tablets: its impact on medical student perceptions of and engagement in learning

    PubMed Central

    Kim, Kyong-Jee; Hwang, Jee-Young

    2016-01-01

    Purpose: Ubiquitous testing has the potential to affect medical education by enhancing the authenticity of the assessment using multimedia items. This study explored medical students’ experience with ubiquitous testing and its impact on student learning. Methods: A cohort (n=48) of third-year students at a medical school in South Korea participated in this study. The students were divided into two groups and were given different versions of 10 content-matched items: one in text version (the text group) and the other in multimedia version (the multimedia group). Multimedia items were delivered using tablets. Item response analyses were performed to compare item characteristics between the two versions. Additionally, focus group interviews were held to investigate the students’ experiences of ubiquitous testing. Results: The mean test score was significantly higher in the text group. Item difficulty and discrimination did not differ between text and multimedia items. The participants generally showed positive responses on ubiquitous testing. Still, they felt that the lectures that they had taken in preclinical years did not prepare them enough for this type of assessment and clinical encounters during clerkships were more helpful. To be better prepared, the participants felt that they needed to engage more actively in learning in clinical clerkships and have more access to multimedia learning resources. Conclusion: Ubiquitous testing can positively affect student learning by reinforcing the importance of being able to understand and apply knowledge in clinical contexts, which drives students to engage more actively in learning in clinical settings. PMID:26838569

  19. PERKAM: Personalized Knowledge Awareness Map for Computer Supported Ubiquitous Learning

    ERIC Educational Resources Information Center

    El-Bishouty, Moushir M.; Ogata, Hiroaki; Yano, Yoneo

    2007-01-01

    This paper introduces a ubiquitous computing environment in order to support the learners while doing tasks; this environment is called PERKAM (PERsonalized Knowledge Awareness Map). PERKAM allows the learners to share knowledge, interact, collaborate, and exchange individual experiences. It utilizes the RFID ubiquities technology to detect the…

  20. Development and Evaluation of a Web 2.0-Based Ubiquitous Learning Platform for Schoolyard Plant Identification

    ERIC Educational Resources Information Center

    Hwang, Gwo-Haur; Chu, Hui-Chun; Chen, Beyin; Cheng, Zheng Shan

    2014-01-01

    The rapid progress of wireless communication, sensing, and mobile technologies has enabled students to learn in an environment that combines learning resources from both the real world and the digital world. It can be viewed as a new learning style which has been called context-aware ubiquitous learning. Most context-aware ubiquitous learning…

  1. Towards a Ubiquitous User Model for Profile Sharing and Reuse

    PubMed Central

    de Lourdes Martinez-Villaseñor, Maria; Gonzalez-Mendoza, Miguel; Hernandez-Gress, Neil

    2012-01-01

    People interact with systems and applications through several devices and are willing to share information about preferences, interests and characteristics. Social networking profiles, data from advanced sensors attached to personal gadgets, and semantic web technologies such as FOAF and microformats are valuable sources of personal information that could provide a fair understanding of the user, but profile information is scattered over different user models. Some researchers in the ubiquitous user modeling community envision the need to share user model's information from heterogeneous sources. In this paper, we address the syntactic and semantic heterogeneity of user models in order to enable user modeling interoperability. We present a dynamic user profile structure based in Simple Knowledge Organization for the Web (SKOS) to provide knowledge representation for ubiquitous user model. We propose a two-tier matching strategy for concept schemas alignment to enable user modeling interoperability. Our proposal is proved in the application scenario of sharing and reusing data in order to deal with overweight and obesity. PMID:23201995

  2. A Wireless Sensor Network-Based Ubiquitous Paprika Growth Management System

    PubMed Central

    Hwang, Jeonghwan; Shin, Changsun; Yoe, Hyun

    2010-01-01

    Wireless Sensor Network (WSN) technology can facilitate advances in productivity, safety and human quality of life through its applications in various industries. In particular, the application of WSN technology to the agricultural area, which is labor-intensive compared to other industries, and in addition is typically lacking in IT technology applications, adds value and can increase the agricultural productivity. This study attempts to establish a ubiquitous agricultural environment and improve the productivity of farms that grow paprika by suggesting a ‘Ubiquitous Paprika Greenhouse Management System’ using WSN technology. The proposed system can collect and monitor information related to the growth environment of crops outside and inside paprika greenhouses by installing WSN sensors and monitoring images captured by CCTV cameras. In addition, the system provides a paprika greenhouse environment control facility for manual and automatic control from a distance, improves the convenience and productivity of users, and facilitates an optimized environment to grow paprika based on the growth environment data acquired by operating the system. PMID:22163543

  3. Physics of magnetospheric boundary layers

    NASA Technical Reports Server (NTRS)

    Cairns, I. H.

    1993-01-01

    The central ideas of this grant are that the magnetospheric boundary layers link disparate regions of the magnetosphere together, and the global behavior of the magnetosphere can be understood only by understanding the linking mechanisms. Accordingly the present grant includes simultaneous research on the global, meso-, and micro-scale physics of the magnetosphere and its boundary layers. These boundary layers include the bow shock, magnetosheath, the plasma sheet boundary layer, and the ionosphere. Analytic, numerical and simulation projects have been performed on these subjects, as well as comparison of theoretical results with observational data. Very good progress has been made, with four papers published or in press and two additional papers submitted for publication during the six month period 1 June - 30 November 1993. At least two projects are currently being written up. In addition, members of the group have given papers at scientific meetings. The further structure of this report is as follows: section two contains brief accounts of research completed during the last six months, while section three describes the research projects intended for the grant's final period.

  4. Social Knowledge Awareness Map for Computer Supported Ubiquitous Learning Environment

    ERIC Educational Resources Information Center

    El-Bishouty, Moushir M.; Ogata, Hiroaki; Rahman, Samia; Yano, Yoneo

    2010-01-01

    Social networks are helpful for people to solve problems by providing useful information. Therefore, the importance of mobile social software for learning has been supported by many researches. In this research, a model of personalized collaborative ubiquitous learning environment is designed and implemented in order to support learners doing…

  5. Criteria, Strategies and Research Issues of Context-Aware Ubiquitous Learning

    ERIC Educational Resources Information Center

    Hwang, Gwo-Jen; Tsai, Chin-Chung; Yang, Stephen J. H.

    2008-01-01

    Recent progress in wireless and sensor technologies has lead to a new development of learning environments, called context-aware ubiquitous learning environment, which is able to sense the situation of learners and provide adaptive supports. Many researchers have been investigating the development of such new learning environments; nevertheless,…

  6. Coevolution of a multilayer node-aligned network whose layers represent different social relations.

    PubMed

    Bahulkar, Ashwin; Szymanski, Boleslaw K; Chan, Kevin; Lizardo, Omar

    2017-01-01

    We examine the coevolution of three-layer node-aligned network of university students. The first layer is defined by nominations based on perceived prominence collected from repeated surveys during the first four semesters; the second is a behavioral layer representing actual students' interactions based on records of mobile calls and text messages; while the third is a behavioral layer representing potential face-to-face interactions suggested by bluetooth collocations. We address four interrelated questions. First, we ask whether the formation or dissolution of a link in one of the layers precedes or succeeds the formation or dissolution of the corresponding link in another layer (temporal dependencies). Second, we explore the causes of observed temporal dependencies between the layers. For those temporal dependencies that are confirmed, we measure the predictive capability of such dependencies. Third, we observe the progress towards nominations and the stages that lead to them. Finally, we examine whether the differences in dissolution rates of symmetric (undirected) versus asymmetric (directed) links co-exist in all layers. We find strong patterns of reciprocal temporal dependencies between the layers. In particular, the creation of an edge in either behavioral layer generally precedes the formation of a corresponding edge in the nomination layer. Conversely, the decay of a link in the nomination layer generally precedes a decline in the intensity of communication and collocation. Finally, nodes connected by asymmetric nomination edges have lower overall communication and collocation volumes and more asymmetric communication flows than the nodes linked by symmetric edges. We find that creation and dissolution of cognitively salient contacts have temporal dependencies with communication and collocation behavior.

  7. CyberPsychological Computation on Social Community of Ubiquitous Learning

    PubMed Central

    Zhou, Xuan; Dai, Genghui; Huang, Shuang; Sun, Xuemin; Hu, Feng; Hu, Hongzhi; Ivanović, Mirjana

    2015-01-01

    Under the modern network environment, ubiquitous learning has been a popular way for people to study knowledge, exchange ideas, and share skills in the cyberspace. Existing research findings indicate that the learners' initiative and community cohesion play vital roles in the social communities of ubiquitous learning, and therefore how to stimulate the learners' interest and participation willingness so as to improve their enjoyable experiences in the learning process should be the primary consideration on this issue. This paper aims to explore an effective method to monitor the learners' psychological reactions based on their behavioral features in cyberspace and therefore provide useful references for adjusting the strategies in the learning process. In doing so, this paper firstly analyzes the psychological assessment of the learners' situations as well as their typical behavioral patterns and then discusses the relationship between the learners' psychological reactions and their observable features in cyberspace. Finally, this paper puts forward a CyberPsychological computation method to estimate the learners' psychological states online. Considering the diversity of learners' habitual behaviors in the reactions to their psychological changes, a BP-GA neural network is proposed for the computation based on their personalized behavioral patterns. PMID:26557846

  8. CyberPsychological Computation on Social Community of Ubiquitous Learning.

    PubMed

    Zhou, Xuan; Dai, Genghui; Huang, Shuang; Sun, Xuemin; Hu, Feng; Hu, Hongzhi; Ivanović, Mirjana

    2015-01-01

    Under the modern network environment, ubiquitous learning has been a popular way for people to study knowledge, exchange ideas, and share skills in the cyberspace. Existing research findings indicate that the learners' initiative and community cohesion play vital roles in the social communities of ubiquitous learning, and therefore how to stimulate the learners' interest and participation willingness so as to improve their enjoyable experiences in the learning process should be the primary consideration on this issue. This paper aims to explore an effective method to monitor the learners' psychological reactions based on their behavioral features in cyberspace and therefore provide useful references for adjusting the strategies in the learning process. In doing so, this paper firstly analyzes the psychological assessment of the learners' situations as well as their typical behavioral patterns and then discusses the relationship between the learners' psychological reactions and their observable features in cyberspace. Finally, this paper puts forward a CyberPsychological computation method to estimate the learners' psychological states online. Considering the diversity of learners' habitual behaviors in the reactions to their psychological changes, a BP-GA neural network is proposed for the computation based on their personalized behavioral patterns.

  9. Fostering Social Engagement and Self-Efficacy in Later Life: Studies with Ubiquitous Computing

    NASA Astrophysics Data System (ADS)

    Morris, Margaret E.; Lundell, Jay; Dishongh, Terry; Needham, Brad

    This chapter describes a multiyear project with a team of social scientists and engineers at Intel focused on emerging technologies and successful aging. Theories of behavioral change are linked to the capabilities of emerging technologies for capturing and reflecting variability in activity and health status. The technologies described in this chapter reflect an attempt to integrate psychological theory and ethnographic research with ubiquitous computing. Ethnographic research that we conducted at the outset of this project consistently underscored the value of social engagement for successful aging. It also pointed out the significant social barriers encountered by many older adults. These barriers - which include changes in lifestyle, mobility, and cognitive functioning - are compounded by a perceived inability to change isolating circumstances. To address these social needs and barriers, we developed a set of prototypes involving sensor networks and feedback displays. This chapter describes the social health technologies that we developed, reactions of the older adults and family caregivers who participated in in-home trials, and implications for future development. We also describe the need for tools to encourage self-awareness and self-efficacy for a broad range of health concerns.

  10. Noise and Vibration Risk Prevention Virtual Web for Ubiquitous Training

    ERIC Educational Resources Information Center

    Redel-Macías, María Dolores; Cubero-Atienza, Antonio J.; Martínez-Valle, José Miguel; Pedrós-Pérez, Gerardo; del Pilar Martínez-Jiménez, María

    2015-01-01

    This paper describes a new Web portal offering experimental labs for ubiquitous training of university engineering students in work-related risk prevention. The Web-accessible computer program simulates the noise and machine vibrations met in the work environment, in a series of virtual laboratories that mimic an actual laboratory and provide the…

  11. DNA cross-linking by dehydromonocrotaline lacks apparent base sequence preference.

    PubMed

    Rieben, W Kurt; Coulombe, Roger A

    2004-12-01

    Pyrrolizidine alkaloids (PAs) are ubiquitous plant toxins, many of which, upon oxidation by hepatic mixed-function oxidases, become reactive bifunctional pyrrolic electrophiles that form DNA-DNA and DNA-protein cross-links. The anti-mitotic, toxic, and carcinogenic action of PAs is thought to be caused, at least in part, by these cross-links. We wished to determine whether the activated PA pyrrole dehydromonocrotaline (DHMO) exhibits base sequence preferences when cross-linked to a set of model duplex poly A-T 14-mer oligonucleotides with varying internal and/or end 5'-d(CG), 5'-d(GC), 5'-d(TA), 5'-d(CGCG), or 5'-d(GCGC) sequences. DHMO-DNA cross-links were assessed by electrophoretic mobility shift assay (EMSA) of 32P endlabeled oligonucleotides and by HPLC analysis of cross-linked DNAs enzymatically digested to their constituent deoxynucleosides. The degree of DNA cross-links depended upon the concentration of the pyrrole, but not on the base sequence of the oligonucleotide target. Likewise, HPLC chromatograms of cross-linked and digested DNAs showed no discernible sequence preference for any nucleotide. Added glutathione, tyrosine, cysteine, and aspartic acid, but not phenylalanine, threonine, serine, lysine, or methionine competed with DNA as alternate nucleophiles for cross-linking by DHMO. From these data it appears that DHMO exhibits no strong base preference when forming cross-links with DNA, and that some cellular nucleophiles can inhibit DNA cross-link formation.

  12. The counterbend dynamics of cross-linked filament bundles and flagella

    PubMed Central

    Coy, Rachel

    2017-01-01

    Cross-linked filament bundles, such as in cilia and flagella, are ubiquitous in biology. They are considered in textbooks as simple filaments with larger stiffness. Recent observations of flagellar counterbend, however, show that induction of curvature in one section of a passive flagellum instigates a compensatory counter-curvature elsewhere, exposing the intricate role of the diminutive cross-linking proteins at large scales. We show that this effect, a material property of the cross-linking mechanics, modifies the bundle dynamics and induces a bimodal L2 − L3 length-dependent material response that departs from the Euler–Bernoulli theory. Hence, the use of simpler theories to analyse experiments can result in paradoxical interpretations. Remarkably, the counterbend dynamics instigates counter-waves in opposition to driven oscillations in distant parts of the bundle, with potential impact on the regulation of flagellar bending waves. These results have a range of physical and biological applications, including the empirical disentanglement of material quantities via counterbend dynamics. PMID:28566516

  13. Physics of magnetospheric boundary layers

    NASA Technical Reports Server (NTRS)

    Cairns, Iver H.

    1995-01-01

    This final report was concerned with the ideas that: (1) magnetospheric boundary layers link disparate regions of the magnetosphere-solar wind system together; and (2) global behavior of the magnetosphere can be understood only by understanding its internal linking mechanisms and those with the solar wind. The research project involved simultaneous research on the global-, meso-, and micro-scale physics of the magnetosphere and its boundary layers, which included the bow shock, the magnetosheath, the plasma sheet boundary layer, and the ionosphere. Analytic, numerical, and simulation projects were performed on these subjects, as well as comparisons of theoretical results with observational data. Other related activity included in the research included: (1) prediction of geomagnetic activity; (2) global MHD (magnetohydrodynamic) simulations; (3) Alfven resonance heating; and (4) Critical Ionization Velocity (CIV) effect. In the appendixes are list of personnel involved, list of papers published; and reprints or photocopies of papers produced for this report.

  14. A Mobile Multi-Agent Information System for Ubiquitous Fetal Monitoring

    PubMed Central

    Su, Chuan-Jun; Chu, Ta-Wei

    2014-01-01

    Electronic fetal monitoring (EFM) systems integrate many previously separate clinical activities related to fetal monitoring. Promoting the use of ubiquitous fetal monitoring services with real time status assessments requires a robust information platform equipped with an automatic diagnosis engine. This paper presents the design and development of a mobile multi-agent platform-based open information systems (IMAIS) with an automated diagnosis engine to support intensive and distributed ubiquitous fetal monitoring. The automatic diagnosis engine that we developed is capable of analyzing data in both traditional paper-based and digital formats. Issues related to interoperability, scalability, and openness in heterogeneous e-health environments are addressed through the adoption of a FIPA2000 standard compliant agent development platform—the Java Agent Development Environment (JADE). Integrating the IMAIS with light-weight, portable fetal monitor devices allows for continuous long-term monitoring without interfering with a patient’s everyday activities and without restricting her mobility. The system architecture can be also applied to vast monitoring scenarios such as elder care and vital sign monitoring. PMID:24452256

  15. Ubiquitous Indoor Geolocation: a Case Study of Jewellery Management System

    NASA Astrophysics Data System (ADS)

    Nikparvar, B.; Sadeghi-Niaraki, A.; Azari, P.

    2014-10-01

    Addressing and geolocation for indoor environments are important fields of research in the recent years. The problem of finding location of objects in indoor spaces is proposed to solve in two ways. The first, is to assign coordinates to objects and second is to divide space into cells and detect the presence or absence of objects in each cell to track them. In this paper the second approach is discussed by using Radio Frequency Identification technology to identify and track high value objects in jewellery retail industry. In Ubiquitous Sensor Networks, the reactivity or proactivity of the environment are important issues. Reactive environments wait for a request to response to it. Instead, in proactive spaces, the environment acts in advance to deal with an expected action. In this research, a geo-sensor network containing RFID readers, tags, and antennas which continuously exchange radio frequency signal streams is proposed to manage and monitor jewellery galleries ubiquitously. The system is also equipped with a GIS representation which provides a more user-friendly system to manage a jewellery gallery.

  16. Ubiquitous Total Station Development using Smartphone, RSSI and Laser Sensor providing service to Ubi-GIS

    NASA Astrophysics Data System (ADS)

    Shoushtari, M. A.; Sadeghi-Niaraki, H.

    2014-10-01

    The growing trend in technological advances and Micro Electro Mechanical Systems (MEMS) has targeted for intelligent human lives. Accordingly, Ubiquitous Computing Approach was proposed by Mark Weiser. This paper proposes an ubiquitous surveying solution in Geometrics and surveying field. Ubiquitous Surveying provides cost-effective, smart and available surveying techniques while traditional surveying equipment are so expensive and have small availability specially in indoor and daily surveying jobs. In order to have a smart surveying instrument, different information technology methods and tools like Triangle method, Received Signal Strength Indicator (RSSI) method and laser sensor are used. These new ways in combine with surveying equations introduces a modern surveying equipment called Ubi-Total Station that also employed different sensors embedded in smartphone and mobile stand. RSSI-based localization and Triangle method technique are easy and well known methods to predict the position of an unknown node in indoor environments whereas additional measures are required for a sufficient accuracy. In this paper the main goal is to introduce the Ubiquitous Total Station as a development in smart and ubiquitous GIS. In order to public use of the surveying equipment, design and implementation of this instrument has been done. Conceptual model of Smartphone-based system is designed for this study and based on this model, an Android application as a first sample is developed. Finally the evaluations shows that absolute errors in X and Y calculation are 0.028 and 0.057 meter respectively. Also RMSE of 0.26 was calculated in RSSI method for distance measurement. The high price of traditional equipment and their requirement for professional surveyors has given way to intelligent surveying. In the suggested system, smartphones can be used as tools for positioning and coordinating geometric information of objects.

  17. Linking magnetic fabric and cumulate texture in layered mafic-ultramafic intrusions (Invited)

    NASA Astrophysics Data System (ADS)

    O Driscoll, B.; Stevenson, C.; Magee, C.

    2013-12-01

    Research on the magnetic fabrics of igneous rocks, pioneered by Balsley and Buddington[1] and Khan[2], has greatly contributed to our understanding of magma dynamics in lava flows, sheet intrusions and plutons over the past five decades. However, considerably few magnetic fabric studies have focused on layered mafic-ultramafic intrusions, particularly ';lopolithic' intrusions, despite the fact that such rocks may preserve a large range of small-scale kinematic structures potentially related to important magma chamber processes. This may be partly due to the fact that mafic-ultramafic cumulates commonly exhibit visible planar fabrics (mineral lamination), as well as compositional layering, in contrast to the frequent absence of such features in granite bodies or fine-grained mafic lava flows. Indeed, debates in the 1970s and 1980s on the development of layering and mineral fabrics in mafic-ultramafic intrusions, focused around the crystal settling versus in situ crystallisation paradigms, are classic in the subject of igneous petrology. Central to these debates is the notion that a wide range of magma chamber processes occur in layered mafic-ultramafic intrusions that are not frequently considered to occur in their relatively viscous granitic counterparts; in essence, the latter have historically been viewed as much more likely to ';freeze-in' a primary magma flow fabric whilst mafic-ultramafic intrusions are subjected to a more protracted solidification history. This wide array of potential initial sources for layering and mineral fabrics in layered mafic-ultramafic intrusions, together with the possible modification of textures at the postcumulus stage, demands a cautious application of any fabric analysis and presents a problem well-suited to interrogation by the AMS technique. The purpose of this contribution is to provide specific context on the application of AMS to elucidating the formation of cumulates in layered mafic-ultramafic intrusions. Examples of AMS

  18. Context-awareness in ubiquitous computing and the mobile devices

    NASA Astrophysics Data System (ADS)

    Akçit, Nuhcan; Tomur, Emrah; Karslıoǧlu, Mahmut Onur

    2015-06-01

    Mobile device use has vastly increased in the last few years. Many people use many mobile devices in their daily lives. Context-aware computing is the main feature of pervasive and ubiquitous computing. Context awareness is also an important topic that becomes more available with ubiquitous computing. As the sensors increase, the data collected via mobile device sensors and sensor networks do not have much value because of the difficulty in analysis and understanding the data. Context-aware computing helps us store contextual information and use or search it by mobile devices when we want to see or analyze it. Contextual data can be made more meaningful by context-aware processing. There are different types of data and context information that must be considered. By combining spatial and contextual data, we obtain more meaningful data based on the entities. Contextual data is any information that can be used to characterize the situation of the entity. The entity is a person, place, or object considered relevant to the interaction between the user and an application, including the users and the applications. Using contextual data and good integration to mobile devices adds great value to this data, and combining these with our other data sets will allow us to obtain more useful information and analysis.

  19. Applying emergent ubiquitous technologies in health: the need to respond to new challenges of opportunity, expectation, and responsibility.

    PubMed

    Rigby, Michael

    2007-12-01

    In spite of their name, 'ubiquitous' technologies are not yet ubiquitous in the true sense of the word, but rather are 'novel', being at the research, pilot, and selective use stages. In future, the proliferation in types of application, the major increase in cases and data volumes, and above all the dependence on ubiquitous technologies to monitor persons at risk, will raise practical, ethical, and liability issues. Equally significantly, it will require health service redesign, including new response services. Health informaticians need to be active in stimulating consideration of all these issues, as part of both social and professional responsibility.

  20. Physical-layer security analysis of PSK quantum-noise randomized cipher in optically amplified links

    NASA Astrophysics Data System (ADS)

    Jiao, Haisong; Pu, Tao; Xiang, Peng; Zheng, Jilin; Fang, Tao; Zhu, Huatao

    2017-08-01

    The quantitative security of quantum-noise randomized cipher (QNRC) in optically amplified links is analyzed from the perspective of physical-layer advantage. Establishing the wire-tap channel models for both key and data, we derive the general expressions of secrecy capacities for the key against ciphertext-only attack and known-plaintext attack, and that for the data, which serve as the basic performance metrics. Further, the maximal achievable secrecy rate of the system is proposed, under which secrecy of both the key and data is guaranteed. Based on the same framework, the secrecy capacities of various cases can be assessed and compared. The results indicate perfect secrecy is potentially achievable for data transmission, and an elementary principle of setting proper number of photons and bases is given to ensure the maximal data secrecy capacity. But the key security is asymptotically perfect, which tends to be the main constraint of systemic maximal secrecy rate. Moreover, by adopting cascaded optical amplification, QNRC can realize long-haul transmission with secure rate up to Gb/s, which is orders of magnitude higher than the perfect secrecy rates of other encryption systems.

  1. A Context-Aware Ubiquitous Learning Environment for Language Listening and Speaking

    ERIC Educational Resources Information Center

    Liu, T.-Y.

    2009-01-01

    This paper reported the results of a study that aimed to construct a sensor and handheld augmented reality (AR)-supported ubiquitous learning (u-learning) environment called the Handheld English Language Learning Organization (HELLO), which is geared towards enhancing students' language learning. The HELLO integrates sensors, AR, ubiquitous…

  2. Two groups of S-layer proteins, SLP1s and SLP2s, in Bacillus thuringiensis co-exist in the S-layer and in parasporal inclusions.

    PubMed

    Zhou, Zhou; Peng, Donghai; Zheng, Jinshui; Guo, Gang; Tian, Longjun; Yu, Ziniu; Sun, Ming

    2011-05-01

    We screened four B. thuringiensis strains whose parasporal inclusions contained the S-layer protein (SLP), and cloned two slp genes from each strain. Phylogenetic analysis indicated these SLPs could be divided into two groups, SLP1s and SLP2s. To confirm whether SLPs were present in the S-layer or as a parasporal inclusion, strains CTC and BMB1152 were chosen for further study. Western blots with whole-cell associated proteins from strains CTC and BMB1152 in the vegetative phase showed that SLP1s and SLP2s were constituents of the S-layer. Immunofluorescence utilizing spore-inclusion mixtures of strains CTC and BMB1152 in the sporulation phase showed that SLP1s and SLP2s were also constituents of parasporal inclusions. When heterogeneously expressed in the crystal negative strain BMB171, four SLPs from strains CTC and BMB1152 could also form parasporal inclusions. This temporal and spatial expression is not an occasional phenomenon but ubiquitous in B. thuringiensis strains.

  3. Adaptation technology between IP layer and optical layer in optical Internet

    NASA Astrophysics Data System (ADS)

    Ji, Yuefeng; Li, Hua; Sun, Yongmei

    2001-10-01

    Wavelength division multiplexing (WDM) optical network provides a platform with high bandwidth capacity and is supposed to be the backbone infrastructure supporting the next-generation high-speed multi-service networks (ATM, IP, etc.). In the foreseeable future, IP will be the predominant data traffic, to make fully use of the bandwidth of the WDM optical network, many attentions have been focused on IP over WDM, which has been proposed as the most promising technology for new kind of network, so-called Optical Internet. According to OSI model, IP is in the 3rd layer (network layer) and optical network is in the 1st layer (physical layer), so the key issue is what adaptation technology should be used in the 2nd layer (data link layer). In this paper, firstly, we analyze and compare the current adaptation technologies used in backbone network nowadays. Secondly, aiming at the drawbacks of above technologies, we present a novel adaptation protocol (DONA) between IP layer and optical layer in Optical Internet and describe it in details. Thirdly, the gigabit transmission adapter (GTA) we accomplished based on the novel protocol is described. Finally, we set up an experiment platform to apply and verify the DONA and GTA, the results and conclusions of the experiment are given.

  4. Developing Ubiquitous Sensor Network Platform Using Internet of Things: Application in Precision Agriculture.

    PubMed

    Ferrández-Pastor, Francisco Javier; García-Chamizo, Juan Manuel; Nieto-Hidalgo, Mario; Mora-Pascual, Jerónimo; Mora-Martínez, José

    2016-07-22

    The application of Information Technologies into Precision Agriculture methods has clear benefits. Precision Agriculture optimises production efficiency, increases quality, minimises environmental impact and reduces the use of resources (energy, water); however, there are different barriers that have delayed its wide development. Some of these main barriers are expensive equipment, the difficulty to operate and maintain and the standard for sensor networks are still under development. Nowadays, new technological development in embedded devices (hardware and communication protocols), the evolution of Internet technologies (Internet of Things) and ubiquitous computing (Ubiquitous Sensor Networks) allow developing less expensive systems, easier to control, install and maintain, using standard protocols with low-power consumption. This work develops and test a low-cost sensor/actuator network platform, based in Internet of Things, integrating machine-to-machine and human-machine-interface protocols. Edge computing uses this multi-protocol approach to develop control processes on Precision Agriculture scenarios. A greenhouse with hydroponic crop production was developed and tested using Ubiquitous Sensor Network monitoring and edge control on Internet of Things paradigm. The experimental results showed that the Internet technologies and Smart Object Communication Patterns can be combined to encourage development of Precision Agriculture. They demonstrated added benefits (cost, energy, smart developing, acceptance by agricultural specialists) when a project is launched.

  5. Developing Ubiquitous Sensor Network Platform Using Internet of Things: Application in Precision Agriculture

    PubMed Central

    Ferrández-Pastor, Francisco Javier; García-Chamizo, Juan Manuel; Nieto-Hidalgo, Mario; Mora-Pascual, Jerónimo; Mora-Martínez, José

    2016-01-01

    The application of Information Technologies into Precision Agriculture methods has clear benefits. Precision Agriculture optimises production efficiency, increases quality, minimises environmental impact and reduces the use of resources (energy, water); however, there are different barriers that have delayed its wide development. Some of these main barriers are expensive equipment, the difficulty to operate and maintain and the standard for sensor networks are still under development. Nowadays, new technological development in embedded devices (hardware and communication protocols), the evolution of Internet technologies (Internet of Things) and ubiquitous computing (Ubiquitous Sensor Networks) allow developing less expensive systems, easier to control, install and maintain, using standard protocols with low-power consumption. This work develops and test a low-cost sensor/actuator network platform, based in Internet of Things, integrating machine-to-machine and human-machine-interface protocols. Edge computing uses this multi-protocol approach to develop control processes on Precision Agriculture scenarios. A greenhouse with hydroponic crop production was developed and tested using Ubiquitous Sensor Network monitoring and edge control on Internet of Things paradigm. The experimental results showed that the Internet technologies and Smart Object Communication Patterns can be combined to encourage development of Precision Agriculture. They demonstrated added benefits (cost, energy, smart developing, acceptance by agricultural specialists) when a project is launched. PMID:27455265

  6. Layer-by-Layer Assembly for Preparation of High-Performance Forward Osmosis Membrane

    NASA Astrophysics Data System (ADS)

    Yang, Libin; Zhang, Jinglong; Song, Peng; Wang, Zhan

    2018-01-01

    Forward osmosis (FO) membrane with high separation performance is needed to promote its practical applications. Herein, layer-by-layer (LbL) approach was used to prepare a thin and highly cross-linked polyamide layer on a polyacrylonitrile substrate surface to prepare a thin-film composite forward osmosis (TFC-FO) membrane with enhanced FO performance. The effects of monomer concentrations and assembly cycles on the performance of the TFC-FO membranes were systematically investigated. Under the optimal preparation condition, TFC-FO membrane achieved the best performance, exhibiting the water flux of 14.4/6.9 LMH and reverse salt flux of 7.7/3.8 gMH under the pressure retarded osmosis/forward osmosis (PRO/FO) mode using 1M NaCl as the draw against a DI-water feed, and a rejection of 96.1% for 2000 mg/L NaCl aqueous solution. The result indicated that layer-by-layer method was a potential method to regulate the structure and performance of the TFC-FO membrane.

  7. Ubiquitous health in practice: the interreality paradigm.

    PubMed

    Gaggioli, Andrea; Raspelli, Simona; Grassi, Alessandra; Pallavicini, Federica; Cipresso, Pietro; Wiederhold, Brenda K; Riva, Giuseppe

    2011-01-01

    In this paper we introduce a new ubiquitous computing paradigm for behavioral health care: "Interreality". Interreality integrates assessment and treatment within a hybrid environment, that creates a bridge between the physical and virtual worlds. Our claim is that bridging virtual experiences (fully controlled by the therapist, used to learn coping skills and emotional regulation) with real experiences (allowing both the identification of any critical stressors and the assessment of what has been learned) using advanced technologies (virtual worlds, advanced sensors and PDA/mobile phones) may improve existing psychological treatment. To illustrate the proposed concept, a clinical scenario is also presented and discussed: Daniela, a 40 years old teacher, with a mother affected by Alzheimer's disease.

  8. A novel ether-linked phytol-containing digalactosylglycerolipid in the marine green alga, Ulva pertusa

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ishibashi, Yohei; Nagamatsu, Yusuke; Miyamoto, Tomofumi

    2014-10-03

    Highlights: • Alkaline-resistant galactolipid, AEGL, was found in marine algae. • The sugar moiety of AEGL is identical to that of digalactosyldiacylglycerol. • AEGL is the first identified glycolipid that possesses an ether-linked phytol. • AEGL is ubiquitously distributed in green, red and brown marine algae. - Abstract: Galactosylglycerolipids (GGLs) and chlorophyll are characteristic components of chloroplast in photosynthetic organisms. Although chlorophyll is anchored to the thylakoid membrane by phytol (tetramethylhexadecenol), this isoprenoid alcohol has never been found as a constituent of GGLs. We here described a novel GGL, in which phytol was linked to the glycerol backbone via anmore » ether linkage. This unique GGL was identified as an Alkaline-resistant and Endogalactosylceramidase (EGALC)-sensitive GlycoLipid (AEGL) in the marine green alga, Ulva pertusa. EGALC is an enzyme that is specific to the R-Galα/β1-6Galβ1-structure of galactolipids. The structure of U. pertusa AEGL was determined following its purification to 1-O-phytyl-3-O-Galα1-6Galβ1-sn-glycerol by mass spectrometric and nuclear magnetic resonance analyses. AEGLs were ubiquitously distributed in not only green, but also red and brown marine algae; however, they were rarely detected in terrestrial plants, eukaryotic phytoplankton, or cyanobacteria.« less

  9. Researching the Ethical Dimensions of Mobile, Ubiquitous and Immersive Technology Enhanced Learning (MUITEL): A Thematic Review and Dialogue

    ERIC Educational Resources Information Center

    Lally, Vic; Sharples, Mike; Tracy, Frances; Bertram, Neil; Masters, Sherriden

    2012-01-01

    In this article, we examine the ethical dimensions of researching the mobile, ubiquitous and immersive technology enhanced learning (MUITEL), with a particular focus on learning in informal settings. We begin with an analysis of the interactions between mobile, ubiquitous and immersive technologies and the wider context of the digital economy. In…

  10. Application of ubiquitous computing in personal health monitoring systems.

    PubMed

    Kunze, C; Grossmann, U; Stork, W; Müller-Glaser, K D

    2002-01-01

    A possibility to significantly reduce the costs of public health systems is to increasingly use information technology. The Laboratory for Information Processing Technology (ITIV) at the University of Karlsruhe is developing a personal health monitoring system, which should improve health care and at the same time reduce costs by combining micro-technological smart sensors with personalized, mobile computing systems. In this paper we present how ubiquitous computing theory can be applied in the health-care domain.

  11. The S-Layer Glycoprotein of the Crenarchaeote Sulfolobus acidocaldarius Is Glycosylated at Multiple Sites with Chitobiose-Linked N-Glycans

    PubMed Central

    Peyfoon, Elham; Meyer, Benjamin; Hitchen, Paul G.; Panico, Maria; Morris, Howard R.; Haslam, Stuart M.; Albers, Sonja-Verena; Dell, Anne

    2010-01-01

    Glycosylation of the S-layer of the crenarchaea Sulfolobus acidocaldarius has been investigated using glycoproteomic methodologies. The mature protein is predicted to contain 31 N-glycosylation consensus sites with approximately one third being found in the C-terminal domain spanning residues L1004-Q1395. Since this domain is rich in Lys and Arg and therefore relatively tractable to glycoproteomic analysis, this study has focused on mapping its N-glycosylation. Our analysis identified nine of the 11 consensus sequence sites, and all were found to be glycosylated. This constitutes a remarkably high glycosylation density in the C-terminal domain averaging one site for each stretch of 30–40 residues. Each of the glycosylation sites observed was shown to be modified with a heterogeneous family of glycans, with the largest having a composition Glc1Man2GlcNAc2 plus 6-sulfoquinovose (QuiS), consistent with the tribranched hexasaccharide previously reported in the cytochrome b558/566 of S. acidocaldarius. S. acidocaldarius is the only archaeal species whose N-glycans are known to be linked via the chitobiose core disaccharide that characterises the N-linked glycans of Eukarya. PMID:20936123

  12. Ubiquitous Knowledge Construction: Mobile Learning Re-Defined and a Conceptual Framework

    ERIC Educational Resources Information Center

    Peng, Hsinyi; Su, Yi-Ju; Chou, Chien; Tsai, Chin-Chung

    2009-01-01

    Emerging from recent mobile technologies, mobile learning, or m-learning, is beginning to offer "stunning new technical capabilities" in education (DiGiano et al., 2003). This new genre of learning is viewed as a revolutionary stage in educational technology. However, ubiquitous computing technologies have given rise to several issues. This…

  13. Ubiquitous and Ambient Intelligence Assisted Learning Environment Infrastructures Development--A Review

    ERIC Educational Resources Information Center

    Kanagarajan, Sujith; Ramakrishnan, Sivakumar

    2018-01-01

    Ubiquitous Learning Environment (ULE) has been becoming a mobile and sensor based technology equipped environment that suits the modern world education discipline requirements for the past few years. Ambient Intelligence (AmI) makes much smarter the ULE by the support of optimization and intelligent techniques. Various efforts have been so far…

  14. A Context-Adaptive Teacher Training Model in a Ubiquitous Learning Environment

    ERIC Educational Resources Information Center

    Chen, Min; Chiang, Feng Kuang; Jiang, Ya Na; Yu, Sheng Quan

    2017-01-01

    In view of the discrepancies in teacher training and teaching practice, this paper put forward a context-adaptive teacher training model in a ubiquitous learning (u-learning) environment. The innovative model provides teachers of different subjects with adaptive and personalized learning content in a u-learning environment, implements intra- and…

  15. Expressing clinical data sets with openEHR archetypes: a solid basis for ubiquitous computing.

    PubMed

    Garde, Sebastian; Hovenga, Evelyn; Buck, Jasmin; Knaup, Petra

    2007-12-01

    The purpose of this paper is to analyse the feasibility and usefulness of expressing clinical data sets (CDSs) as openEHR archetypes. For this, we present an approach to transform CDS into archetypes, and outline typical problems with CDS and analyse whether some of these problems can be overcome by the use of archetypes. Literature review and analysis of a selection of existing Australian, German, other European and international CDSs; transfer of a CDS for Paediatric Oncology into openEHR archetypes; implementation of CDSs in application systems. To explore the feasibility of expressing CDS as archetypes an approach to transform existing CDSs into archetypes is presented in this paper. In case of the Paediatric Oncology CDS (which consists of 260 data items) this lead to the definition of 48 openEHR archetypes. To analyse the usefulness of expressing CDS as archetypes, we identified nine problems with CDS that currently remain unsolved without a common model underpinning the CDS. Typical problems include incompatible basic data types and overlapping and incompatible definitions of clinical content. A solution to most of these problems based on openEHR archetypes is motivated. With regard to integrity constraints, further research is required. While openEHR cannot overcome all barriers to Ubiquitous Computing, it can provide the common basis for ubiquitous presence of meaningful and computer-processable knowledge and information, which we believe is a basic requirement for Ubiquitous Computing. Expressing CDSs as openEHR archetypes is feasible and advantageous as it fosters semantic interoperability, supports ubiquitous computing, and helps to develop archetypes that are arguably of better quality than the original CDS.

  16. Ubiquitous Multicriteria Clinic Recommendation System.

    PubMed

    Chen, Toly

    2016-05-01

    Advancements in information, communication, and sensor technologies have led to new opportunities in medical care and education. Patients in general prefer visiting the nearest clinic, attempt to avoid waiting for treatment, and have unequal preferences for different clinics and doctors. Therefore, to enable patients to compare multiple clinics, this study proposes a ubiquitous multicriteria clinic recommendation system. In this system, patients can send requests through their cell phones to the system server to obtain a clinic recommendation. Once the patient sends this information to the system, the system server first estimates the patient's speed according to the detection results of a global positioning system. It then applies a fuzzy integer nonlinear programming-ordered weighted average approach to assess four criteria and finally recommends a clinic with maximal utility to the patient. The proposed methodology was tested in a field experiment, and the experimental results showed that it is advantageous over two existing methods in elevating the utilities of recommendations. In addition, such an advantage was shown to be statistically significant.

  17. Ubiquitous and temperature-dependent neural plasticity in hibernators.

    PubMed

    von der Ohe, Christina G; Darian-Smith, Corinna; Garner, Craig C; Heller, H Craig

    2006-10-11

    Hibernating mammals are remarkable for surviving near-freezing brain temperatures and near cessation of neural activity for a week or more at a time. This extreme physiological state is associated with dendritic and synaptic changes in hippocampal neurons. Here, we investigate whether these changes are a ubiquitous phenomenon throughout the brain that is driven by temperature. We iontophoretically injected Lucifer yellow into several types of neurons in fixed slices from hibernating ground squirrels. We analyzed neuronal microstructure from animals at several stages of torpor at two different ambient temperatures, and during the summer. We show that neuronal cell bodies, dendrites, and spines from several cell types in hibernating ground squirrels retract on entry into torpor, change little over the course of several days, and then regrow during the 2 h return to euthermia. Similar structural changes take place in neurons from the hippocampus, cortex, and thalamus, suggesting a global phenomenon. Investigation of neural microstructure from groups of animals hibernating at different ambient temperatures revealed that there is a linear relationship between neural retraction and minimum body temperature. Despite significant temperature-dependent differences in extent of retraction during torpor, recovery reaches the same final values of cell body area, dendritic arbor complexity, and spine density. This study demonstrates large-scale and seemingly ubiquitous neural plasticity in the ground squirrel brain during torpor. It also defines a temperature-driven model of dramatic neural plasticity, which provides a unique opportunity to explore mechanisms of large-scale regrowth in adult mammals, and the effects of remodeling on learning and memory.

  18. Transformation of multiwall carbon nanotubes to onions with layers cross-linked by sp3 bonds under high pressure and shear deformation

    NASA Astrophysics Data System (ADS)

    Pankov, A. M.; Bredikhina, A. S.; Kulnitskiy, B. A.; Perezhogin, I. A.; Skryleva, E. A.; Parkhomenko, Yu. N.; Popov, M. Yu.; Blank, V. D.

    2017-08-01

    A pressure-induced phase transition of multiwall carbon nanotubes (MWNT) to a new structure at room temperature is studied using a shear diamond anvil cell, X-ray photoelectron spectra (XPS), transmission electron microscope (TEM) and Raman procedures. We observe a cardinal pressure-induced change in the nanoparticles shape from multi-shell tubes to multi-shell spheres. MWNT transforms to onions with layers cross-linked by sp3 bonds under the 45-65 GPa compressive stress combined with shear deformation at room temperature. TEM and XPS results show that about 40% of the carbon atoms in the new phase are sp3-bounded.

  19. Phonon conductivity metrics for compact, linked-cage, layered, and filled-cage crystals, using ab initio, molecular dynamics and Boltzmann transport treatments

    NASA Astrophysics Data System (ADS)

    Huang, Baoling

    Atomic-level thermal transport in compact, layered, linked-cage, and filled-cage crystals is investigated using a multiscale approach, combines the ab initio calculation, molecular dynamics (MD), Boltzman transport equations (BTE), and the kinetic theory. These materials are of great interests in energy storage, transport, and conversion. The structural metrics of phonon conductivity of these crystals are then explored. An atomic structure-based model is developed for the understanding the relationship between the atomic structure and phonon transport in compact crystals at high temperatures. The elemental electronegativity, element mass, and the arrangement of bonds are found to be the dominant factors to determine the phonon conductivity. As an example of linked-cage crystals, the phonon conductivity of MOF-5 is investigated over a wide temperature range using MD simulations and the Green-Kubo method. The temperature dependence of the thermal conductivity of MOF-5 is found to be weak at high temperatures, which results from the suppression of the long-range acoustic phonon transport by the special linked-cage structure. The mean free path of the majority of phonons in MOF-5 is limited by the cage size. The phonon and electron transport in layered Bi2Te3 structure are investigated using the first-principle calculations, MD, and BTE. Strong anisotropy has been found for both phonon and electron transport due to the special layered structure. The long-range acoustic phonons dominate the phonon transport with a strong temperature and direction dependence. Temperature dependence of the energy gap and appropriate modelling of relaxation times are found to be important for the prediction of the electrical transport in the intrinsic regime. The scattering by the acoustic, optical, and polar-optical phonons are found to dominate the electron transport. For filled skutterudite structure, strong coupling between the filler and the host is found, which contradicts the

  20. Toward Ubiquitous Communication Platform for Emergency Medical Care

    NASA Astrophysics Data System (ADS)

    Ishibashi, Kenichi; Morishima, Naoto; Kanbara, Masayuki; Sunahara, Hideki; Imanishi, Masami

    Interaction between emergency medical technicians (EMTs) and doctors is essential in emergency medical care. Doctors require diverse information related to a patient to provide efficient aid. In 2005, we started the Ikoma119 project and have developed a ubiquitous communication platform for emergency medical care called Mobile ER. Our platform, which is based on wireless internet technology, has such desirable properties as low-cost, location-independent service, and ease of service introduction. We provide an overview of our platform and describe the services that we have developed. We also discuss the remaining issues to realize our platform's actual operation.

  1. Adjustable link for kinematic mounting systems

    DOEpatents

    Hale, Layton C.

    1997-01-01

    An adjustable link for kinematic mounting systems. The adjustable link is a low-cost, passive device that provides backlash-free adjustment along its single constraint direction and flexural freedom in all other directions. The adjustable link comprises two spheres, two sockets in which the spheres are adjustable retain, and a connection link threadly connected at each end to the spheres, to provide a single direction of restraint and to adjust the length or distance between the sockets. Six such adjustable links provide for six degrees of freedom for mounting an instrument on a support. The adjustable link has applications in any machine or instrument requiring precision adjustment in six degrees of freedom, isolation from deformations of the supporting platform, and/or additional structural damping. The damping is accomplished by using a hollow connection link that contains an inner rod and a viscoelastic separation layer between the two.

  2. Adjustable link for kinematic mounting systems

    DOEpatents

    Hale, L.C.

    1997-07-01

    An adjustable link for kinematic mounting systems is disclosed. The adjustable link is a low-cost, passive device that provides backlash-free adjustment along its single constraint direction and flexural freedom in all other directions. The adjustable link comprises two spheres, two sockets in which the spheres are adjustable retain, and a connection link threadly connected at each end to the spheres, to provide a single direction of restraint and to adjust the length or distance between the sockets. Six such adjustable links provide for six degrees of freedom for mounting an instrument on a support. The adjustable link has applications in any machine or instrument requiring precision adjustment in six degrees of freedom, isolation from deformations of the supporting platform, and/or additional structural damping. The damping is accomplished by using a hollow connection link that contains an inner rod and a viscoelastic separation layer between the two. 3 figs.

  3. Feminist Articulations, Social Literacies, and Ubiquitous Mobile Technology Use in Kenya

    ERIC Educational Resources Information Center

    Sanya, Brenda N.; Odero, Phantus W.

    2017-01-01

    This article examines the changes occurring in learning and literacy in the age of ubiquitous mobile phone use. Focusing on rural Kenyan women's use of mobile phone technologies in civic education programs, mobile banking, and to contact family members, the article explores how these women's use of mobile phones, based on their everyday needs, has…

  4. Four Stages of Research on the Educational Use of Ubiquitous Computing

    ERIC Educational Resources Information Center

    Laru, Jari; Naykki, Piia; Järvelä, Sanna

    2015-01-01

    In this paper, the Gartner Group's hype cycle is used as the basis for categorizing and analyzing research on the educational use of ubiquitous computing. There are five phases of the hype cycle: the technology trigger, the peak of inflated expectations, the trough of disillusionment, the slope of enlightenment, and the plateau of productivity.…

  5. College Students' Conceptions of Context-Aware Ubiquitous Learning: A Phenomenographic Analysis

    ERIC Educational Resources Information Center

    Tsai, Pei-Shan; Tsai, Chin-Chung; Hwang, Gwo-Haur

    2011-01-01

    The purpose of this study was to explore students' conceptions of context-aware ubiquitous learning (u-learning). The students participated in a u-learning exercise using PDAs equipped with RFID readers. The data were collected from individual interviews with each of the students by a trained researcher, and the responses of the interviewees were…

  6. PHARMACEUTICALS AS UBIQUITOUS POLLUTANTS ...

    EPA Pesticide Factsheets

    Those chemical pollutants that are regulated under various international, federal, and state programs represent but a small fraction of the universe of chemicals that occur in the environment as a result of both natural processes and human influence. Although this galaxy of targeted chemicals might be minuscule compared with the universe of both known and yet-to-be identified chemicals, an implicit assumption is that these selective lists of chemicals are responsible for the most significant share of risk with respect to environmental or economic impairment or to human health. Pharmaceuticals and personal care products (PPCPs) comprise a particularly large and diverse array of unregulated pollutants that occur in the environment from the combined activities and actions of multitudes of individuals as well as from veterinary and agricultural use. Although the concentration of any individual PPCP rarely ever exceeds the sub-ppm level (if present in drinking water, concentrations of individual PPCPs are generally less than the ppt-ppb level), evidence is accumulating that these trace-Ievel pollutants are ubiquitous, they can have a continuous presence regardless of environmental half-lives ( e.g., where sanitary wastewaters enter the environment), and the numbers of distinct and varied chemical entities could be extremely large (given that thousands are in commercial use). The research focused on in the subtasks is the development and application of state-of the-ar

  7. Epstein-Barr virus and rheumatoid arthritis: is there a link?

    PubMed

    Costenbader, Karen H; Karlson, Elizabeth W

    2006-01-01

    Rheumatoid arthritis is a systemic autoimmune disease characterized by chronic, destructive, debilitating arthritis. Its etiology is unknown; it is presumed that environmental factors trigger development in the genetically predisposed. Epstein-Barr virus, a nearly ubiquitous virus in the human population, has generated great interest as a potential trigger. This virus stimulates polyclonal lymphocyte expansion and persists within B lymphocytes for the host's life, inhibited from reactivating by the immune response. In latent and replicating forms, it has immunomodulating actions that could play a role in the development of this autoimmune disease. The evidence linking Epstein-Barr virus and rheumatoid arthritis is reviewed.

  8. Supporting Teacher Orchestration in Ubiquitous Learning Environments: A Study in Primary Education

    ERIC Educational Resources Information Center

    Muñoz-Cristóbal, Juan A.; Jorrín-Abellán, Iván M.; Asensio-Pérez, Juan I.; Martínez-Monés, Alejandra; Prieto, Luis P.; Dimitriadis, Yannis

    2015-01-01

    During the last decades, educational contexts have transformed into complex technological and social ecologies, with mobile devices expanding the scope of education beyond the traditional classroom, creating so-called Ubiquitous Learning Environments (ULEs). However, these new technological opportunities entail an additional burden for teachers,…

  9. A communication model to integrate the Request-Response and the Publish-Subscribe paradigms into ubiquitous systems.

    PubMed

    Rodríguez-Domínguez, Carlos; Benghazi, Kawtar; Noguera, Manuel; Garrido, José Luis; Rodríguez, María Luisa; Ruiz-López, Tomás

    2012-01-01

    The Request-Response (RR) paradigm is widely used in ubiquitous systems to exchange information in a secure, reliable and timely manner. Nonetheless, there is also an emerging need for adopting the Publish-Subscribe (PubSub) paradigm in this kind of systems, due to the advantages that this paradigm offers in supporting mobility by means of asynchronous, non-blocking and one-to-many message distribution semantics for event notification. This paper analyzes the strengths and weaknesses of both the RR and PubSub paradigms to support communications in ubiquitous systems and proposes an abstract communication model in order to enable their seamless integration. Thus, developers will be focused on communication semantics and the required quality properties, rather than be concerned about specific communication mechanisms. The aim is to provide developers with abstractions intended to decrease the complexity of integrating different communication paradigms commonly needed in ubiquitous systems. The proposal has been applied to implement a middleware and a real home automation system to show its applicability and benefits.

  10. Reflection Paper on a Ubiquitous English Vocabulary Learning System: Evidence of Active/Passive Attitude vs. Usefulness/Ease-of-Use

    ERIC Educational Resources Information Center

    Lim, Jeff

    2013-01-01

    "A ubiquitous English vocabulary learning system: evidence of active/passive attitudes vs. usefulness/ease-of-use" introduces and develops "Ubiquitous English Vocabulary Learning" (UEFL) system. It introduces to the memorization using the video clips. According to their paper the video clip gives a better chance for students to…

  11. Sublayer of Prandtl Boundary Layers

    NASA Astrophysics Data System (ADS)

    Grenier, Emmanuel; Nguyen, Toan T.

    2018-03-01

    The aim of this paper is to investigate the stability of Prandtl boundary layers in the vanishing viscosity limit {ν \\to 0} . In Grenier (Commun Pure Appl Math 53(9):1067-1091, 2000), one of the authors proved that there exists no asymptotic expansion involving one of Prandtl's boundary layer, with thickness of order {√{ν}} , which describes the inviscid limit of Navier-Stokes equations. The instability gives rise to a viscous boundary sublayer whose thickness is of order {ν^{3/4}} . In this paper, we point out how the stability of the classical Prandtl's layer is linked to the stability of this sublayer. In particular, we prove that the two layers cannot both be nonlinearly stable in L^∞. That is, either the Prandtl's layer or the boundary sublayer is nonlinearly unstable in the sup norm.

  12. Quantitative Nanomechanical Properties of Multilayer Films Made of Polysaccharides through Spray Assisted Layer-by-Layer Assembly.

    PubMed

    Criado, Miryam; Rebollar, Esther; Nogales, Aurora; Ezquerra, Tiberio A; Boulmedais, Fouzia; Mijangos, Carmen; Hernández, Rebeca

    2017-01-09

    Nanomechanical properties of alginate/chitosan (Alg/Chi) multilayer films, obtained through spray assisted layer-by-layer assembly, were studied by means of PeakForce quantitative nanomechanical mapping atomic force microscopy (PF-QNM AFM). Prepared at two different alginate concentrations (1.0 and 2.5 mg/mL) and a fixed chitosan concentration (1.0 mg/mL), Alg/Chi films have an exponential growth in thickness with a transition to a linear growth toward a plateau by increasing the number of deposited bilayers. Height, elastic modulus, deformation, and adhesion maps were simultaneously recorded depending on the number of deposited bilayers. The elastic modulus of Alg/Chi films was found to be related to the mechanism of growth in contrast to the adhesion and deformation. A comparison of the nanomechanical properties obtained for non-cross-linked and thermally cross-linked Alg/Chi films revealed an increase of the elastic modulus after cross-linking regardless alginate concentration. The incorporation of iron oxide nanoparticles (NPs), during the spray preparation of the films, gave rise to nanocomposite Alg/Chi films with increased elastic moduli with the number of incorporated NPs layers. Deformation maps of the films strongly suggested the presence of empty spaces associated with the method of preparation. Finally, adhesion measurements point out to a significant role of NPs on the increase of the adhesion values found for nanocomposite films.

  13. HSDPA (3.5G)-based ubiquitous integrated biotelemetry system for emergency care.

    PubMed

    Kang, Jaemin; Shin, Il Hyung; Koo, Yoonseo; Jung, Min Yang; Suh, Gil Joon; Kim, Hee Chan

    2007-01-01

    We have developed the second prototype system of Ubiquitous Integrated Biotelemetry System for Emergency Care(UIBSEC) using a HSDPA(High Speed Downlink Packet Access) modem to be used by emergency rescuers to get directions from medical doctors in providing emergency medical services for patients in ambulance. Five vital bio-signal instrumentation modules have been implemented, which include noninvasive arterial blood pressure (NIBP), arterial oxygen saturation (SaO2), 6-channel electro-cardiogram(ECG), blood glucose level, and body temperature and real-time motion picture of the patient and GPS information are also taken. Measured patient data, captured motion picture and GPS information are then transferred to a doctor's PC through the HSDPA and TCP/IP networks using stand-alone HSDPA modem. Most prominent feature of the developed system is that it is based on the HSDPA backbone networks available in Korea now, through which we will be able to establish a ubiquitous emergency healthcare service system.

  14. Real-time long term measurement using integrated framework for ubiquitous smart monitoring

    NASA Astrophysics Data System (ADS)

    Heo, Gwanghee; Lee, Giu; Lee, Woosang; Jeon, Joonryong; Kim, Pil-Joong

    2007-04-01

    Ubiquitous monitoring combining internet technologies and wireless communication is one of the most promising technologies of infrastructure health monitoring against the natural of man-made hazards. In this paper, an integrated framework of the ubiquitous monitoring is developed for real-time long term measurement in internet environment. This framework develops a wireless sensor system based on Bluetooth technology and sends measured acceleration data to the host computer through TCP/IP protocol. And it is also designed to respond to the request of web user on real time basis. In order to verify this system, real time monitoring tests are carried out on a prototype self-anchored suspension bridge. Also, wireless measurement system is analyzed to estimate its sensing capacity and evaluate its performance for monitoring purpose. Based on the evaluation, this paper proposes the effective strategies for integrated framework in order to detect structural deficiencies and to design an early warning system.

  15. Ubiquitous health monitoring and real-time cardiac arrhythmias detection: a case study.

    PubMed

    Li, Jian; Zhou, Haiying; Zuo, Decheng; Hou, Kun-Mean; De Vaulx, Christophe

    2014-01-01

    As the symptoms and signs of heart diseases that cause sudden cardiac death, cardiac arrhythmia has attracted great attention. Due to limitations in time and space, traditional approaches to cardiac arrhythmias detection fail to provide a real-time continuous monitoring and testing service applicable in different environmental conditions. Integrated with the latest technologies in ECG (electrocardiograph) analysis and medical care, the pervasive computing technology makes possible the ubiquitous cardiac care services, and thus brings about new technical challenges, especially in the formation of cardiac care architecture and realization of the real-time automatic ECG detection algorithm dedicated to care devices. In this paper, a ubiquitous cardiac care prototype system is presented with its architecture framework well elaborated. This prototype system has been tested and evaluated in all the clinical-/home-/outdoor-care modes with a satisfactory performance in providing real-time continuous cardiac arrhythmias monitoring service unlimitedly adaptable in time and space.

  16. "Mobile Nurse" platform for ubiquitous medicine.

    PubMed

    Struzik, Z R; Yoshiuchi, K; Sone, M; Ishikawa, T; Kikuchi, H; Kumano, H; Watsuji, T; Natelson, B H; Yamamoto, Y

    2007-01-01

    We introduce "Mobile Nurse" (MN) - an emerging platform for the practice of ubiquitous medicine. By implementing in a dynamic setting of daily life the patient care traditionally provided by the clinical nurses on duty, MN aims at integral data collection and shortening the response time to the patient. MN is also capable of intelligent interaction with the patient and is able to learn from the patient's behavior and disease sign evaluation for improved personalized treatment. In this paper, we outline the most essential concepts around the hardware, software and methodological designs of MN. We provide an example of the implementation, and elaborate on the possible future impact on medical practice and biomedical science research. The main innovation of MN, setting it apart from current tele-medicine systems, is the ability to integrate the patient's signs and symptoms on site, providing medical professionals with powerful tools to elucidate disease mechanisms, to make proper diagnoses and to prescribe treatment.

  17. Well-Constructed Single-Layer Molybdenum Disulfide Nanorose Cross-Linked by Three Dimensional-Reduced Graphene Oxide Network for Superior Water Splitting and Lithium Storage Property

    PubMed Central

    Zhao, Yanyan; Kuai, Long; Liu, Yanguo; Wang, Pengpeng; Arandiyan, Hamidreza; Cao, Sufeng; Zhang, Jie; Li, Fengyun; Wang, Qing; Geng, Baoyou; Sun, Hongyu

    2015-01-01

    A facile one-step solution reaction route for growth of novel MoS2 nanorose cross-linked by 3D rGO network, in which the MoS2 nanorose is constructed by single-layered or few-layered MoS2 nanosheets, is presented. Due to the 3D assembled hierarchical architecture of the ultrathin MoS2 nanosheets and the interconnection of 3D rGO network, as well as the synergetic effects of MoS2 and rGO, the as-prepared MoS2-NR/rGO nanohybrids delivered high specific capacity, excellent cycling and good rate performance when evaluated as an anode material for lithium-ion batteries. Moreover, the nanohybrids also show excellent hydrogen-evolution catalytic activity and durability in an acidic medium, which is superior to MoS2 nanorose and their nanoparticles counterparts. PMID:25735416

  18. Ubiquitous Technology in Healthcare and Teaching-Learning: Scourge or Blessing?

    PubMed

    Yancey, Nan Russell

    2017-07-01

    The author in this article introduces a discussion of one school of nursing's efforts integrating telehealth education into undergraduate and graduate curricula using King's theory of goal attainment as a guide. The introduction shares a story of loss in a rural setting without access to quality healthcare to highlight the blessing technology may be. However, challenges are discussed that arise through the ubiquitous use of technology in person-to-person communication and relationships.

  19. Developing and evaluating Quilts for the depiction of large layered graphs.

    PubMed

    Bae, Juhee; Watson, Ben

    2011-12-01

    Traditional layered graph depictions such as flow charts are in wide use. Yet as graphs grow more complex, these depictions can become difficult to understand. Quilts are matrix-based depictions for layered graphs designed to address this problem. In this research, we first improve Quilts by developing three design alternatives, and then compare the best of these alternatives to better-known node-link and matrix depictions. A primary weakness in Quilts is their depiction of skip links, links that do not simply connect to a succeeding layer. Therefore in our first study, we compare Quilts using color-only, text-only, and mixed (color and text) skip link depictions, finding that path finding with the color-only depiction is significantly slower and less accurate, and that in certain cases, the mixed depiction offers an advantage over the text-only depiction. In our second study, we compare Quilts using the mixed depiction to node-link diagrams and centered matrices. Overall results show that users can find paths through graphs significantly faster with Quilts (46.6 secs) than with node-link (58.3 secs) or matrix (71.2 secs) diagrams. This speed advantage is still greater in large graphs (e.g. in 200 node graphs, 55.4 secs vs. 71.1 secs for node-link and 84.2 secs for matrix depictions). © 2011 IEEE

  20. Design and Implementation of Ubiquitous Health System U-Health Using Smart-Watches Sensors

    NASA Astrophysics Data System (ADS)

    Razavi Termeh, V.; Sadeghi Niaraki, A.

    2015-12-01

    Today as diseases grow rapidly, the responsibilities of the health clinics in giving services to patients increase and patients have to be more monitored and controlled. Remote systems of monitoring patients result in reducing cost, ease of movement, and also persistent control of patients by their doctors, so that patient can be monitored without need to go to the clinic. Recent advances in the field of ubiquitous sciences as well as using smartphones have resulted in increasingly use of this devices in remote monitoring of patients. The aim of this paper is to design and implement a ubiquitous health system using smartphones and sensors of smart-watches. This is accomplished through the information sent to the smartphone from the sensors of the watch, e.g. heart beat measurement sensor and ultraviolet ray. Then, this information is analyzed in the smartphone and some information based on the position of the patient and the path of him/her using GIS analyses as well as the information about the health level of the patient is sent to the doctor via SMS or phone call. Unnatural heart beats can be resulted in diseases such as Heart Failure and Arterial Fibrillation. With the approach adopted in this study, the patient or the doctor could be aware of these diseases at any time. The proposed approach is a low cost, without need to complex and resilient equipment, system in ubiquitous health that does not limit the movement of the patient.

  1. Subsurface chlorophyll maximum layers: enduring enigma or mystery solved?

    PubMed

    Cullen, John J

    2015-01-01

    The phenomenon of subsurface chlorophyll maximum layers (SCMLs) is not a unique ecological response to environmental conditions; rather, a broad range of interacting processes can contribute to the formation of persistent layers of elevated chlorophyll a concentration (Chl) that are nearly ubiquitous in stratified surface waters. Mechanisms that contribute to the formation and maintenance of the SCMLs include a local maximum in phytoplankton growth rate near the nutricline, photoacclimation of pigment content that leads to elevated Chl relative to phytoplankton biomass at depth, and a range of physiologically influenced swimming behaviors in motile phytoplankton and buoyancy control in diatoms and cyanobacteria that can lead to aggregations of phytoplankton in layers, subject to grazing and physical control. A postulated typical stable water structure characterizes consistent patterns in vertical profiles of Chl, phytoplankton biomass, nutrients, and light across a trophic gradient structured by the vertical flux of nutrients and characterized by the average daily irradiance at the nutricline. Hypothetical predictions can be tested using a nascent biogeochemical global ocean observing system. Partial results to date are generally consistent with predictions based on current knowledge, which has strong roots in research from the twentieth century.

  2. Conditions for Ubiquitous Computing: What Can Be Learned from a Longitudinal Study

    ERIC Educational Resources Information Center

    Lei, Jing

    2010-01-01

    Based on survey data and interview data collected over four academic years, this longitudinal study examined how a ubiquitous computing project evolved along with the changes in teachers, students, the human infrastructure, and technology infrastructure in the school. This study also investigated what conditions were necessary for successful…

  3. Percolation in multiplex networks with overlap.

    PubMed

    Cellai, Davide; López, Eduardo; Zhou, Jie; Gleeson, James P; Bianconi, Ginestra

    2013-11-01

    From transportation networks to complex infrastructures, and to social and communication networks, a large variety of systems can be described in terms of multiplexes formed by a set of nodes interacting through different networks (layers). Multiplexes may display an increased fragility with respect to the single layers that constitute them. However, so far the overlap of the links in different layers has been mostly neglected, despite the fact that it is an ubiquitous phenomenon in most multiplexes. Here, we show that the overlap among layers can improve the robustness of interdependent multiplex systems and change the critical behavior of the percolation phase transition in a complex way.

  4. A group evolving-based framework with perturbations for link prediction

    NASA Astrophysics Data System (ADS)

    Si, Cuiqi; Jiao, Licheng; Wu, Jianshe; Zhao, Jin

    2017-06-01

    Link prediction is a ubiquitous application in many fields which uses partially observed information to predict absence or presence of links between node pairs. The group evolving study provides reasonable explanations on the behaviors of nodes, relations between nodes and community formation in a network. Possible events in group evolution include continuing, growing, splitting, forming and so on. The changes discovered in networks are to some extent the result of these events. In this work, we present a group evolving-based characterization of node's behavioral patterns, and via which we can estimate the probability they tend to interact. In general, the primary aim of this paper is to offer a minimal toy model to detect missing links based on evolution of groups and give a simpler explanation on the rationality of the model. We first introduce perturbations into networks to obtain stable cluster structures, and the stable clusters determine the stability of each node. Then fluctuations, another node behavior, are assumed by the participation of each node to its own belonging group. Finally, we demonstrate that such characteristics allow us to predict link existence and propose a model for link prediction which outperforms many classical methods with a decreasing computational time in large scales. Encouraging experimental results obtained on real networks show that our approach can effectively predict missing links in network, and even when nearly 40% of the edges are missing, it also retains stationary performance.

  5. Thermal Boundary Layer Equation for Turbulent Rayleigh-Bénard Convection

    NASA Astrophysics Data System (ADS)

    Ching, Emily Sc; Shishkina, Olga; Horn, Susanne; Wagner, Sebastian

    Turbulent Rayleigh-Bénard convection, consisting of a fluid confined between two horizontal plates, heated from below and cooled from above, is a paradigm system for studying turbulent thermal convection, which is ubiquitous in nature. In turbulent Rayleigh-Bénard convection, there are viscous boundary layers near all rigid walls and two thermal boundary layers, one above the bottom plate and one below the top plate. The classical Prandtl-Blasius-Pohlhausen theory has often been used to describe the mean velocity and temperature boundary layer profiles but systematic deviations are known to exist. These deviations are due to turbulent fluctuations. In this talk, we report a new thermal boundary layer equation for turbulent Rayleigh-Bénard convection derived for Prandtl number (Pr) greater than 1, which takes into account the effects of turbulent fluctuations by using the idea of an eddy thermal diffusivity. Solving this equation, we have obtained two analytical mean temperature profiles for Pr ~ 1 and Pr >> 1 . These two theoretical predictions are shown to be in excellent agreement with the results of our direct numerical simulations for Pr=4.38 (water) and Pr=2547.9 (glycerol). Work of ESCC was supported by the Hong Kong Research Grants Council under Grant No. CUHK-400311.

  6. A Communication Model to Integrate the Request-Response and the Publish-Subscribe Paradigms into Ubiquitous Systems

    PubMed Central

    Rodríguez-Domínguez, Carlos; Benghazi, Kawtar; Noguera, Manuel; Garrido, José Luis; Rodríguez, María Luisa; Ruiz-López, Tomás

    2012-01-01

    The Request-Response (RR) paradigm is widely used in ubiquitous systems to exchange information in a secure, reliable and timely manner. Nonetheless, there is also an emerging need for adopting the Publish-Subscribe (PubSub) paradigm in this kind of systems, due to the advantages that this paradigm offers in supporting mobility by means of asynchronous, non-blocking and one-to-many message distribution semantics for event notification. This paper analyzes the strengths and weaknesses of both the RR and PubSub paradigms to support communications in ubiquitous systems and proposes an abstract communication model in order to enable their seamless integration. Thus, developers will be focused on communication semantics and the required quality properties, rather than be concerned about specific communication mechanisms. The aim is to provide developers with abstractions intended to decrease the complexity of integrating different communication paradigms commonly needed in ubiquitous systems. The proposal has been applied to implement a middleware and a real home automation system to show its applicability and benefits. PMID:22969366

  7. Ubiquitous Computing and Changing Pedagogical Possibilities: Representations, Conceptualizations and Uses of Knowledge

    ERIC Educational Resources Information Center

    Swan, Karen; Van 'T Hooft, Mark; Kratcoski, Annette; Schenker, Jason

    2007-01-01

    This article reports on preliminary findings from an ongoing study of teaching and learning in a ubiquitous computing classroom. The research employed mixed methods and multiple measures to document changes in teaching and learning that result when teachers and students have access to a variety of digital devices wherever and whenever they need…

  8. A Model for Ubiquitous Serious Games Development Focused on Problem Based Learning

    ERIC Educational Resources Information Center

    Dorneles, Sandro Oliveira; da Costa, Cristiano André; Rigo, Sandro José

    2015-01-01

    The possibility of using serious games with problem-based learning opens up huge opportunities to connect the experiences of daily life of students with learning. In this context, this article presents a model for serious and ubiquitous games development, focusing on problem based learning methodology. The model allows teachers to create games…

  9. Development and Evaluation of a Context-Aware Ubiquitous Learning Environment for Astronomy Education

    ERIC Educational Resources Information Center

    Chen, Chia-Chen; Lin, Pei-Hsuan

    2016-01-01

    In recent years information technology has been integrated into education to produce a series of trends, beginning with "electronic learning" (e-learning), through "mobile learning" (m-learning) and finally to "ubiquitous learning" (u-learning), which aims to improve learner motivation through overcoming the…

  10. DS-ARP: A New Detection Scheme for ARP Spoofing Attacks Based on Routing Trace for Ubiquitous Environments

    PubMed Central

    Song, Min Su; Lee, Jae Dong; Jeong, Hwa-Young; Park, Jong Hyuk

    2014-01-01

    Despite the convenience, ubiquitous computing suffers from many threats and security risks. Security considerations in the ubiquitous network are required to create enriched and more secure ubiquitous environments. The address resolution protocol (ARP) is a protocol used to identify the IP address and the physical address of the associated network card. ARP is designed to work without problems in general environments. However, since it does not include security measures against malicious attacks, in its design, an attacker can impersonate another host using ARP spoofing or access important information. In this paper, we propose a new detection scheme for ARP spoofing attacks using a routing trace, which can be used to protect the internal network. Tracing routing can find the change of network movement path. The proposed scheme provides high constancy and compatibility because it does not alter the ARP protocol. In addition, it is simple and stable, as it does not use a complex algorithm or impose extra load on the computer system. PMID:25243205

  11. DS-ARP: a new detection scheme for ARP spoofing attacks based on routing trace for ubiquitous environments.

    PubMed

    Song, Min Su; Lee, Jae Dong; Jeong, Young-Sik; Jeong, Hwa-Young; Park, Jong Hyuk

    2014-01-01

    Despite the convenience, ubiquitous computing suffers from many threats and security risks. Security considerations in the ubiquitous network are required to create enriched and more secure ubiquitous environments. The address resolution protocol (ARP) is a protocol used to identify the IP address and the physical address of the associated network card. ARP is designed to work without problems in general environments. However, since it does not include security measures against malicious attacks, in its design, an attacker can impersonate another host using ARP spoofing or access important information. In this paper, we propose a new detection scheme for ARP spoofing attacks using a routing trace, which can be used to protect the internal network. Tracing routing can find the change of network movement path. The proposed scheme provides high constancy and compatibility because it does not alter the ARP protocol. In addition, it is simple and stable, as it does not use a complex algorithm or impose extra load on the computer system.

  12. Remote Sensing Observations and Numerical Simulation for Martian Layered Ejecta Craters

    NASA Astrophysics Data System (ADS)

    Li, L.; Yue, Z.; Zhang, C.; Li, D.

    2018-04-01

    To understand past Martian climates, it is important to know the distribution and nature of water ice on Mars. Impact craters are widely used ubiquitous indicators for the presence of subsurface water or ice on Mars. Remote sensing observations and numerical simulation are powerful tools for investigating morphological and topographic features on planetary surfaces, and we can use the morphology of layered ejecta craters and hydrocode modeling to constrain possible layering and impact environments. The approach of this work consists of three stages. Firstly, the morphological characteristics of the Martian layered ejecta craters are performed based on Martian images and DEM data. Secondly, numerical modeling layered ejecta are performed through the hydrocode iSALE (impact-SALE). We present hydrocode modeling of impacts onto targets with a single icy layer within an otherwise uniform basalt crust to quantify the effects of subsurface H2O on observable layered ejecta morphologies. The model setup is based on a layered target made up of a regolithic layer (described by the basalt ANEOS), on top an ice layer (described by ANEOS equation of H2O ice), in turn on top of an underlying basaltic crust. The bolide is a 0.8 km diameter basaltic asteroid hitting the Martian surface vertically at a velocity of 12.8 km/s. Finally, the numerical results are compared with the MOLA DEM profile in order to analyze the formation mechanism of Martian layered ejecta craters. Our simulations suggest that the presence of an icy layer significantly modifies the cratering mechanics, and many of the unusual features of SLE craters may be explained by the presence of icy layers. Impact cratering on icy satellites is significantly affected by the presence of subsurface H2O.

  13. Epstein–Barr virus and rheumatoid arthritis: is there a link?

    PubMed Central

    Costenbader, Karen H; Karlson, Elizabeth W

    2006-01-01

    Rheumatoid arthritis is a systemic autoimmune disease characterized by chronic, destructive, debilitating arthritis. Its etiology is unknown; it is presumed that environmental factors trigger development in the genetically predisposed. Epstein–Barr virus, a nearly ubiquitous virus in the human population, has generated great interest as a potential trigger. This virus stimulates polyclonal lymphocyte expansion and persists within B lymphocytes for the host's life, inhibited from reactivating by the immune response. In latent and replicating forms, it has immunomodulating actions that could play a role in the development of this autoimmune disease. The evidence linking Epstein–Barr virus and rheumatoid arthritis is reviewed. PMID:16542469

  14. Mobile-PKI Service Model for Ubiquitous Environment

    NASA Astrophysics Data System (ADS)

    Jeun, Inkyung; Chun, Kilsoo

    One of the most important things in PKI(Public Key Infrastructure) is the private key management issue. The private key must be deal with safely for secure PKI service. Even though PKI service is usually used for identification and authentication of user in e-commerce, PKI service has many inconvenient factors. Especially, the fact that storage media of private key for PKI service is limited to PC hard disk drive or smart card users must always carry, gives an inconvenience to user and is not suitable in ubiquitous network. This paper suggests the digital signature service using a mobile phone(m-PKI service) which is suitable in future network. A mobile phone is the most widely used for personal communication means and has a characteristic of high movability. We can use the PKI service anytime and anywhere using m-PKI.

  15. copia-like retrotransposons are ubiquitous among plants.

    PubMed Central

    Voytas, D F; Cummings, M P; Koniczny, A; Ausubel, F M; Rodermel, S R

    1992-01-01

    Transposable genetic elements are assumed to be a feature of all eukaryotic genomes. Their identification, however, has largely been haphazard, limited principally to organisms subjected to molecular or genetic scrutiny. We assessed the phylogenetic distribution of copia-like retrotransposons, a class of transposable element that proliferates by reverse transcription, using a polymerase chain reaction assay designed to detect copia-like element reverse transcriptase sequences. copia-like retrotransposons were identified in 64 plant species as well as the photosynthetic protist Volvox carteri. The plant species included representatives from 9 of 10 plant divisions, including bryophytes, lycopods, ferns, gymnosperms, and angiosperms. DNA sequence analysis of 29 cloned PCR products and of a maize retrotransposon cDNA confirmed the identity of these sequences as copia-like reverse transcriptase sequences, thereby demonstrating that this class of retrotransposons is a ubiquitous component of plant genomes. Images PMID:1379734

  16. S-Layer Protein-Based Biosensors.

    PubMed

    Schuster, Bernhard

    2018-04-11

    The present paper highlights the application of bacterial surface (S-) layer proteins as versatile components for the fabrication of biosensors. One technologically relevant feature of S-layer proteins is their ability to self-assemble on many surfaces and interfaces to form a crystalline two-dimensional (2D) protein lattice. The S-layer lattice on the surface of a biosensor becomes part of the interface architecture linking the bioreceptor to the transducer interface, which may cause signal amplification. The S-layer lattice as ultrathin, highly porous structure with functional groups in a well-defined special distribution and orientation and an overall anti-fouling characteristics can significantly raise the limit in terms of variety and the ease of bioreceptor immobilization, compactness of bioreceptor molecule arrangement, sensitivity, specificity, and detection limit for many types of biosensors. The present paper discusses and summarizes examples for the successful implementation of S-layer lattices on biosensor surfaces in order to give a comprehensive overview on the application potential of these bioinspired S-layer protein-based biosensors.

  17. Some guidelines for the ethical development of ubiquitous computing.

    PubMed

    Greenfield, Adam

    2008-10-28

    At a time when both the landscape of everyday life and the choices available to us there are increasingly conditioned by ubiquitous information processing systems, it seems wise to articulate some general principles guiding their ethical design and deployment. I here enunciate five broad guidelines for the designers of such systems, including recommendations that they be devised in such a way as to default to harmlessness, be conservative of time, be conservative of face, be self-disclosing and be deniable. I conclude with some observations about the likelihood of any such principles winning usefully widespread voluntary adherence.

  18. Ozone Layer Research and Technical Resources

    EPA Pesticide Factsheets

    Access information on research and technical resources related to ozone layer science. This page provides links to research efforts led by organizations such as the National Oceanic and Atmospheric Administration, the United Nations Environment Program, an

  19. The challenge of ubiquitous computing in health care: technology, concepts and solutions. Findings from the IMIA Yearbook of Medical Informatics 2005.

    PubMed

    Bott, O J; Ammenwerth, E; Brigl, B; Knaup, P; Lang, E; Pilgram, R; Pfeifer, B; Ruderich, F; Wolff, A C; Haux, R; Kulikowski, C

    2005-01-01

    To review recent research efforts in the field of ubiquitous computing in health care. To identify current research trends and further challenges for medical informatics. Analysis of the contents of the Yearbook on Medical Informatics 2005 of the International Medical Informatics Association (IMIA). The Yearbook of Medical Informatics 2005 includes 34 original papers selected from 22 peer-reviewed scientific journals related to several distinct research areas: health and clinical management, patient records, health information systems, medical signal processing and biomedical imaging, decision support, knowledge representation and management, education and consumer informatics as well as bioinformatics. A special section on ubiquitous health care systems is devoted to recent developments in the application of ubiquitous computing in health care. Besides additional synoptical reviews of each of the sections the Yearbook includes invited reviews concerning E-Health strategies, primary care informatics and wearable healthcare. Several publications demonstrate the potential of ubiquitous computing to enhance effectiveness of health services delivery and organization. But ubiquitous computing is also a societal challenge, caused by the surrounding but unobtrusive character of this technology. Contributions from nearly all of the established sub-disciplines of medical informatics are demanded to turn the visions of this promising new research field into reality.

  20. Development and Evaluation of an RFID-Based Ubiquitous Learning Environment for Outdoor Learning

    ERIC Educational Resources Information Center

    Tan, Tan-Hsu; Liu, Tsung-Yu; Chang, Chi-Cheng

    2007-01-01

    Many issues have been identified in outdoor teaching, especially in places that lack the capacity to effectively present information about such subjects as historical relics, rare animals, and geological landscapes. This study proposes an Environment of Ubiquitous Learning with Educational Resources (EULER) based on radio frequency identification…

  1. A Framework for Real-Time Collection, Analysis, and Classification of Ubiquitous Infrasound Data

    NASA Astrophysics Data System (ADS)

    Christe, A.; Garces, M. A.; Magana-Zook, S. A.; Schnurr, J. M.

    2015-12-01

    Traditional infrasound arrays are generally expensive to install and maintain. There are ~10^3 infrasound channels on Earth today. The amount of data currently provided by legacy architectures can be processed on a modest server. However, the growing availability of low-cost, ubiquitous, and dense infrasonic sensor networks presents a substantial increase in the volume, velocity, and variety of data flow. Initial data from a prototype ubiquitous global infrasound network is already pushing the boundaries of traditional research server and communication systems, in particular when serving data products over heterogeneous, international network topologies. We present a scalable, cloud-based approach for capturing and analyzing large amounts of dense infrasonic data (>10^6 channels). We utilize Akka actors with WebSockets to maintain data connections with infrasound sensors. Apache Spark provides streaming, batch, machine learning, and graph processing libraries which will permit signature classification, cross-correlation, and other analytics in near real time. This new framework and approach provide significant advantages in scalability and cost.

  2. Reassembly of S-layer proteins

    NASA Astrophysics Data System (ADS)

    Pum, Dietmar; Sleytr, Uwe B.

    2014-08-01

    Crystalline bacterial cell surface layers (S-layers) represent the outermost cell envelope component in a broad range of bacteria and archaea. They are monomolecular arrays composed of a single protein or glycoprotein species and represent the simplest biological membranes developed during evolution. They are highly porous protein mesh works with unit cell sizes in the range of 3 to 30 nm, and pore sizes of 2 to 8 nm. S-layers are usually 5 to 20 nm thick (in archaea, up to 70 nm). S-layer proteins are one of the most abundant biopolymers on earth. One of their key features, and the focus of this review, is the intrinsic capability of isolated native and recombinant S-layer proteins to form self-assembled mono- or double layers in suspension, at solid supports, the air-water interface, planar lipid films, liposomes, nanocapsules, and nanoparticles. The reassembly is entropy-driven and a fascinating example of matrix assembly following a multistage, non-classical pathway in which the process of S-layer protein folding is directly linked with assembly into extended clusters. Moreover, basic research on the structure, synthesis, genetics, assembly, and function of S-layer proteins laid the foundation for their application in novel approaches in biotechnology, biomimetics, synthetic biology, and nanotechnology.

  3. KODAMA and VPC based Framework for Ubiquitous Systems and its Experiment

    NASA Astrophysics Data System (ADS)

    Takahashi, Kenichi; Amamiya, Satoshi; Iwao, Tadashige; Zhong, Guoqiang; Kainuma, Tatsuya; Amamiya, Makoto

    Recently, agent technologies have attracted a lot of interest as an emerging programming paradigm. With such agent technologies, services are provided through collaboration among agents. At the same time, the spread of mobile technologies and communication infrastructures has made it possible to access the network anytime and from anywhere. Using agents and mobile technologies to realize ubiquitous computing systems, we propose a new framework based on KODAMA and VPC. KODAMA provides distributed management mechanisms by using the concept of community and communication infrastructure to deliver messages among agents without agents being aware of the physical network. VPC provides a method of defining peer-to-peer services based on agent communication with policy packages. By merging the characteristics of both KODAMA and VPC functions, we propose a new framework for ubiquitous computing environments. It provides distributed management functions according to the concept of agent communities, agent communications which are abstracted from the physical environment, and agent collaboration with policy packages. Using our new framework, we conducted a large-scale experiment in shopping malls in Nagoya, which sent advertisement e-mails to users' cellular phones according to user location and attributes. The empirical results showed that our new framework worked effectively for sales in shopping malls.

  4. Evaluation of the impact of furniture on communications performance for ubiquitous deployment of Wireless Sensor Networks in smart homes.

    PubMed

    Bleda, Andrés L; Jara, Antonio J; Maestre, Rafael; Santa, Guadalupe; Gómez Skarmeta, Antonio F

    2012-01-01

    The extensions of the environment with the integration of sensing systems in any space, in conjunction with ubiquitous computing are enabling the so-called Smart Space Sensor Networks. This new generation of networks are offering full connectivity with any object, through the Internet of Things (IoT) and/or the Web, i.e., the Web of Things. These connectivity capabilities are making it feasible to sense the behaviours of people at home and act accordingly. These sensing systems must be integrated within typical elements found at home such as furniture. For that reason, this work considers furniture as an interesting element for the transparent location of sensors. Furniture is a ubiquitous object, i.e., it can be found everywhere at home or the office, and it can integrate and hide the sensors of a network. This work addresses the lack of an exhaustive study of the effect of furniture on signal losses. In addition an easy-to-use tool for estimating the robustness of the communication channel among the sensor nodes and gateways is proposed. Specifically, the losses in a sensor network signal due to the materials found within the communication link are evaluated. Then, this work proposes a software tool that gathers the obtained results and is capable of evaluating the impact of a given set of materials on the communications. This tool also provides a mechanism to optimize the sensor network deployments during the definition of smart spaces. Specifically, it provides information such as: maximum distances between sensor nodes, most suitable type of furniture to integrate sensors, or battery life of sensor nodes. This tool has been validated empirically in the lab, and it is currently being used by several enterprise partners of the Technological Centre of Furniture and Wood in the southeast of Spain.

  5. Evaluation of the Impact of Furniture on Communications Performance for Ubiquitous Deployment of Wireless Sensor Networks in Smart Homes

    PubMed Central

    Bleda, Andrés L.; Jara, Antonio J.; Maestre, Rafael; Santa, Guadalupe; Gómez Skarmeta, Antonio F.

    2012-01-01

    The extensions of the environment with the integration of sensing systems in any space, in conjunction with ubiquitous computing are enabling the so-called Smart Space Sensor Networks. This new generation of networks are offering full connectivity with any object, through the Internet of Things (IoT) and/or the Web, i.e., the Web of Things. These connectivity capabilities are making it feasible to sense the behaviours of people at home and act accordingly. These sensing systems must be integrated within typical elements found at home such as furniture. For that reason, this work considers furniture as an interesting element for the transparent location of sensors. Furniture is a ubiquitous object, i.e., it can be found everywhere at home or the office, and it can integrate and hide the sensors of a network. This work addresses the lack of an exhaustive study of the effect of furniture on signal losses. In addition an easy-to-use tool for estimating the robustness of the communication channel among the sensor nodes and gateways is proposed. Specifically, the losses in a sensor network signal due to the materials found within the communication link are evaluated. Then, this work proposes a software tool that gathers the obtained results and is capable of evaluating the impact of a given set of materials on the communications. This tool also provides a mechanism to optimize the sensor network deployments during the definition of smart spaces. Specifically, it provides information such as: maximum distances between sensor nodes, most suitable type of furniture to integrate sensors, or battery life of sensor nodes. This tool has been validated empirically in the lab, and it is currently being used by several enterprise partners of the Technological Centre of Furniture and Wood in the southeast of Spain. PMID:22778653

  6. A Modeling Pattern for Layered System Interfaces

    NASA Technical Reports Server (NTRS)

    Shames, Peter M.; Sarrel, Marc A.

    2015-01-01

    Communications between systems is often initially represented at a single, high level of abstraction, a link between components. During design evolution it is usually necessary to elaborate the interface model, defining it from several different, related viewpoints and levels of abstraction. This paper presents a pattern to model such multi-layered interface architectures simply and efficiently, in a way that supports expression of technical complexity, interfaces and behavior, and analysis of complexity. Each viewpoint and layer of abstraction has its own properties and behaviors. System elements are logically connected both horizontally along the communication path, and vertically across the different layers of protocols. The performance of upper layers depends on the performance of lower layers, yet the implementation of lower layers is intentionally opaque to upper layers. Upper layers are hidden from lower layers except as sources and sinks of data. The system elements may not be linked directly at each horizontal layer but only via a communication path, and end-to-end communications may depend on intermediate components that are hidden from them, but may need to be shown in certain views and analyzed for certain purposes. This architectural model pattern uses methods described in ISO 42010, Recommended Practice for Architectural Description of Software-intensive Systems and CCSDS 311.0-M-1, Reference Architecture for Space Data Systems (RASDS). A set of useful viewpoints and views are presented, along with the associated modeling representations, stakeholders and concerns. These viewpoints, views, and concerns then inform the modeling pattern. This pattern permits viewing the system from several different perspectives and at different layers of abstraction. An external viewpoint treats the systems of interest as black boxes and focuses on the applications view, another view exposes the details of the connections and other components between the black boxes

  7. Implementation of a Cross-Layer Sensing Medium-Access Control Scheme.

    PubMed

    Su, Yishan; Fu, Xiaomei; Han, Guangyao; Xu, Naishen; Jin, Zhigang

    2017-04-10

    In this paper, compressed sensing (CS) theory is utilized in a medium-access control (MAC) scheme for wireless sensor networks (WSNs). We propose a new, cross-layer compressed sensing medium-access control (CL CS-MAC) scheme, combining the physical layer and data link layer, where the wireless transmission in physical layer is considered as a compress process of requested packets in a data link layer according to compressed sensing (CS) theory. We first introduced using compressive complex requests to identify the exact active sensor nodes, which makes the scheme more efficient. Moreover, because the reconstruction process is executed in a complex field of a physical layer, where no bit and frame synchronizations are needed, the asynchronous and random requests scheme can be implemented without synchronization payload. We set up a testbed based on software-defined radio (SDR) to implement the proposed CL CS-MAC scheme practically and to demonstrate the validation. For large-scale WSNs, the simulation results show that the proposed CL CS-MAC scheme provides higher throughput and robustness than the carrier sense multiple access (CSMA) and compressed sensing medium-access control (CS-MAC) schemes.

  8. Undergraduate Students' Opinions with Regard to Ubiquitous MOOC for Enhancing Cross-Cultural Competence

    ERIC Educational Resources Information Center

    Plangsorn, Boonrat; Na-Songkhla, Jaitip; Luetkehans, Lara M.

    2016-01-01

    The purpose of this study was to study undergraduate students' opinions with regard to the ubiquitous massive open online course (MOOC) for enhancing cross-cultural competence. This descriptive research applied a survey method. The survey data were collected by using survey questionnaires and online questionnaires from 410 undergraduate students…

  9. Effects of Teaching and Learning Styles on Students' Reflection Levels for Ubiquitous Learning

    ERIC Educational Resources Information Center

    Hsieh, Sheng-Wen; Jang, Yu-Ruei; Hwang, Gwo-Jen; Chen, Nian-Shing

    2011-01-01

    Ubiquitous learning (u-learning), in conjunction with supports from the digital world, is recognized as an effective approach for situating students in real-world learning environments. Earlier studies concerning u-learning have mainly focused on investigating the learning attitudes and learning achievements of students, while the causations such…

  10. Global Dosage Compensation Is Ubiquitous in Lepidoptera, but Counteracted by the Masculinization of the Z Chromosome

    PubMed Central

    Huylmans, Ann Kathrin; Macon, Ariana; Vicoso, Beatriz

    2017-01-01

    Abstract While chromosome-wide dosage compensation of the X chromosome has been found in many species, studies in ZW clades have indicated that compensation of the Z is more localized and/or incomplete. In the ZW Lepidoptera, some species show complete compensation of the Z chromosome, while others lack full equalization, but what drives these inconsistencies is unclear. Here, we compare patterns of male and female gene expression on the Z chromosome of two closely related butterfly species, Papilio xuthus and Papilio machaon, and in multiple tissues of two moths species, Plodia interpunctella and Bombyx mori, which were previously found to differ in the extent to which they equalize Z-linked gene expression between the sexes. We find that, while some species and tissues seem to have incomplete dosage compensation, this is in fact due to the accumulation of male-biased genes and the depletion of female-biased genes on the Z chromosome. Once this is accounted for, the Z chromosome is fully compensated in all four species, through the up-regulation of Z expression in females and in some cases additional down-regulation in males. We further find that both sex-biased genes and Z-linked genes have increased rates of expression divergence in this clade, and that this can lead to fast shifts in patterns of gene expression even between closely related species. Taken together, these results show that the uneven distribution of sex-biased genes on sex chromosomes can confound conclusions about dosage compensation and that Z chromosome-wide dosage compensation is not only possible but ubiquitous among Lepidoptera. PMID:28957502

  11. Bioorthogonal layer-by-layer encapsulation of pancreatic islets via hyperbranched polymers

    PubMed Central

    Gattás-Asfura, Kerim M.; Stabler, Cherie L.

    2013-01-01

    The encapsulation of viable tissues via layer-by-layer polymer assembly provides a versatile platform for cell surface engineering, with nanoscale control over capsule properties. Herein, we report the development of a hyperbranched polymer-based, ultrathin capsule architecture expressing bioorthogonal functionality and tailored physiochemical properties. Random carbodiimide-based condensation of 3,5-dicarboxyphenyl glycineamide on alginate yielded a highly branched polysaccharide with multiple, spatially restricted, and readily functionalizable terminal carboxylate moieties. Poly(ethylene glycol) (PEG) was utilized to link azido end groups to the structured alginate. Together with phosphine functionalized poly(amido amine) (PAMAM) dendrimer, nanoscale layer-by-layer coatings, covalently stabilized via Staudinger ligation, were assembled onto solid surfaces and pancreatic islets. The effects of electrostatic and/or bioorthogonal covalent interlayer interactions on the resulting coating efficiency and stability, as well as pancreatic islet viability and function, were studied. These hyperbranched polymers provide a flexible platform for the formation of covalently stabilized ultrathin coatings on viable cells and tissues. In addition, the hyperbranched nature of the polymers presents a highly functionalized surface capable of bioorthogonal conjugation of additional bioactive or labeling motifs. PMID:24063764

  12. The Ideas of Greek High School Students about the "Ozone Layer."

    ERIC Educational Resources Information Center

    Boyes, Edward; Stanisstreet, Martin; Papantoniou, Vasso Spiliotopoulou

    1999-01-01

    Describes a study of Greek high school students' (n=116) perceptions of the ozone layer. Finds that students have a good understanding of the position and purpose of the ozone layer in terms of protection from ultraviolet rays, but students also hold misconceptions linking the ozone layer to the greenhouse effect and other forms of local…

  13. Ubiquitous virtual private network: a solution for WSN seamless integration.

    PubMed

    Villa, David; Moya, Francisco; Villanueva, Félix Jesús; Aceña, Óscar; López, Juan Carlos

    2014-01-06

    Sensor networks are becoming an essential part of ubiquitous systems and applications. However, there are no well-defined protocols or mechanisms to access the sensor network from the enterprise information system. We consider this issue as a heterogeneous network interconnection problem, and as a result, the same concepts may be applied. Specifically, we propose the use of object-oriented middlewares to provide a virtual private network in which all involved elements (sensor nodes or computer applications) will be able to communicate as if all of them were in a single and uniform network.

  14. Ubiquitous Virtual Private Network: A Solution for WSN Seamless Integration

    PubMed Central

    Villa, David; Moya, Francisco; Villanueva, Félix Jesús; Aceña, Óscar; López, Juan Carlos

    2014-01-01

    Sensor networks are becoming an essential part of ubiquitous systems and applications. However, there are no well-defined protocols or mechanisms to access the sensor network from the enterprise information system. We consider this issue as a heterogeneous network interconnection problem, and as a result, the same concepts may be applied. Specifically, we propose the use of object-oriented middlewares to provide a virtual private network in which all involved elements (sensor nodes or computer applications) will be able to communicate as if all of them were in a single and uniform network. PMID:24399154

  15. A multilayer network analysis of hashtags in twitter via co-occurrence and semantic links

    NASA Astrophysics Data System (ADS)

    Türker, Ilker; Sulak, Eyüb Ekmel

    2018-02-01

    Complex network studies, as an interdisciplinary framework, span a large variety of subjects including social media. In social networks, several mechanisms generate miscellaneous structures like friendship networks, mention networks, tag networks, etc. Focusing on tag networks (namely, hashtags in twitter), we made a two-layer analysis of tag networks from a massive dataset of Twitter entries. The first layer is constructed by converting the co-occurrences of these tags in a single entry (tweet) into links, while the second layer is constructed converting the semantic relations of the tags into links. We observed that the universal properties of the real networks like small-world property, clustering and power-law distributions in various network parameters are also evident in the multilayer network of hashtags. Moreover, we outlined that co-occurrences of hashtags in tweets are mostly coupled with semantic relations, whereas a small number of semantically unrelated, therefore random links reduce node separation and network diameter in the co-occurrence network layer. Together with the degree distributions, the power-law consistencies of degree difference, edge weight and cosine similarity distributions in both layers are also appealing forms of Zipf’s law evident in nature.

  16. A Heuristic Algorithm for Planning Personalized Learning Paths for Context-Aware Ubiquitous Learning

    ERIC Educational Resources Information Center

    Hwang, Gwo-Jen; Kuo, Fan-Ray; Yin, Peng-Yeng; Chuang, Kuo-Hsien

    2010-01-01

    In a context-aware ubiquitous learning environment, learning systems can detect students' learning behaviors in the real-world with the help of context-aware (sensor) technology; that is, students can be guided to observe or operate real-world objects with personalized support from the digital world. In this study, an optimization problem that…

  17. Bringing Mohamed to the Mountain: Situated Professional Development in a Ubiquitous Computing Classroom

    ERIC Educational Resources Information Center

    Swan, Karen; Kratcoski, Annette; Mazzer, Pat; Schenker, Jason

    2005-01-01

    This article describes an ongoing situated professional development program in which teachers bring their intact classes for an extended stay in a ubiquitous computing environment equipped with a variety of state-of-the-art computing devices. The experience is unique in that it not only situates teacher learning about technology integration in…

  18. Security policies and trust in ubiquitous computing.

    PubMed

    Joshi, Anupam; Finin, Tim; Kagal, Lalana; Parker, Jim; Patwardhan, Anand

    2008-10-28

    Ubiquitous environments comprise resource-constrained mobile and wearable devices and computational elements embedded in everyday artefacts. These are connected to each other using both infrastructure-based as well as short-range ad hoc networks. Limited Internet connectivity limits the use of conventional security mechanisms such as public key infrastructures and other forms of server-centric authentication. Under these circumstances, peer-to-peer interactions are well suited for not just information interchange, but also managing security and privacy. However, practical solutions for protecting mobile devices, preserving privacy, evaluating trust and determining the reliability and accuracy of peer-provided data in such interactions are still in their infancy. Our research is directed towards providing stronger assurances of the reliability and trustworthiness of information and services, and the use of declarative policy-driven approaches to handle the open and dynamic nature of such systems. This paper provides an overview of some of the challenges and issues, and points out directions for progress.

  19. Embedded ubiquitous services on hospital information systems.

    PubMed

    Kuroda, Tomohiro; Sasaki, Hiroshi; Suenaga, Takatoshi; Masuda, Yasushi; Yasumuro, Yoshihiro; Hori, Kenta; Ohboshi, Naoki; Takemura, Tadamasa; Chihara, Kunihiro; Yoshihara, Hiroyuki

    2012-11-01

    A Hospital Information Systems (HIS) have turned a hospital into a gigantic computer with huge computational power, huge storage and wired/wireless local area network. On the other hand, a modern medical device, such as echograph, is a computer system with several functional units connected by an internal network named a bus. Therefore, we can embed such a medical device into the HIS by simply replacing the bus with the local area network. This paper designed and developed two embedded systems, a ubiquitous echograph system and a networked digital camera. Evaluations of the developed systems clearly show that the proposed approach, embedding existing clinical systems into HIS, drastically changes productivity in the clinical field. Once a clinical system becomes a pluggable unit for a gigantic computer system, HIS, the combination of multiple embedded systems with application software designed under deep consideration about clinical processes may lead to the emergence of disruptive innovation in the clinical field.

  20. Active Learning with Ubiquitous Presenter and Tablet PCs

    NASA Astrophysics Data System (ADS)

    Price, Edward; Simon, B.

    2006-12-01

    Ubiquitous Presenter (UP)* is a digital presentation system that facilitates spontaneity and interactivity in the classroom. Using the system, an instructor with a Tablet PC can spontaneously modify prepared slides. Furthermore, students with web-enabled devices can add digital 'ink' or text to the instructor's slides and submit them to the instructor during class. We have used this system to facilitate interactive engagement techniques in an introductory physics class where approximately one-third of the students had access to a Tablet PC during class. Class time was used for Interactive Lecture Demonstrations, Peer Instruction, and group problem solving. We describe the implementation of these active learning activities with UP and Tablet PCs, show examples of student contributions, and describe the impact on the classroom setting. *http://up.ucsd.edu/about/

  1. A pervasive health monitoring service system based on ubiquitous network technology.

    PubMed

    Lin, Chung-Chih; Lee, Ren-Guey; Hsiao, Chun-Chieh

    2008-07-01

    The phenomenon of aging society has derived problems such as shortage of medical resources and reduction of quality in healthcare services. This paper presents a system infrastructure for pervasive and long-term healthcare applications, i.e. a ubiquitous network composed of wireless local area network (WLAN) and cable television (CATV) network serving as a platform for monitoring physiological signals. Users can record vital signs including heart rate, blood pressure, and body temperature anytime either at home or at frequently visited public places in order to create a personal health file. The whole system was formally implemented in December 2004. Analysis of 2000 questionnaires indicates that 85% of users were satisfied with the provided community-wide healthcare services. Among the services provided by our system, health consultation services offered by family doctors was rated the most important service by 17.9% of respondents, and was followed by control of one's own health condition (16.4% of respondents). Convenience of data access was rated most important by roughly 14.3% of respondents. We proposed and implemented a long-term healthcare system integrating WLAN and CATV networks in the form of a ubiquitous network providing a service platform for physiological monitoring. This system can classify the health levels of the resident according to the variation tendency of his or her physiological signal for important reference of health management.

  2. Nonlinear fluid dynamics of nanoscale hydration water layer

    NASA Astrophysics Data System (ADS)

    Jhe, Wonho; Kim, Bongsu; Kim, Qhwan; An, Sangmin

    In nature, the hydration water layer (HWL) ubiquitously exists in ambient conditions or aqueous solutions, where water molecules are tightly bound to ions or hydrophilic surfaces. It plays an important role in various mechanisms such as biological processes, abiotic materials, colloidal interaction, and friction. The HWL, for example, can be easily formed between biomaterials since most biomaterials are covered by hydrophilic molecules such as lipid bilayers, and this HWL is expected to be significant to biological and physiological functions. Here (1) we present the general stress tensor of the hydration water layer. The hydration stress tensor provided the platform form for holistic understanding of the dynamic behaviors of the confined HWL including tapping and shear dynamics which are until now individually studied. And, (2) through fast shear velocity ( 1mm/s) experiments, the elastic turbulence caused by elastic property of the HWL is indirectly observed. Our results may contribute to a deeper study of systems where the HWL plays an important role such as biomolecules, colloidal particles, and the MEMS. This work was supported by the National Research Foundation of Korea(NRF) Grant funded by the Korea government(MSIP) (2016R1A3B1908660).

  3. Chaotic Stochasticity: A Ubiquitous Source of Unpredictability in Epidemics

    NASA Astrophysics Data System (ADS)

    Rand, D. A.; Wilson, H. B.

    1991-11-01

    We address the question of whether or not childhood epidemics such as measles and chickenpox are chaotic, and argue that the best explanation of the observed unpredictability is that it is a manifestation of what we call chaotic stochasticity. Such chaos is driven and made permanent by the fluctuations from the mean field encountered in epidemics, or by extrinsic stochastic noise, and is dependent upon the existence of chaotic repellors in the mean field dynamics. Its existence is also a consequence of the near extinctions in the epidemic. For such systems, chaotic stochasticity is likely to be far more ubiquitous than the presence of deterministic chaotic attractors. It is likely to be a common phenomenon in biological dynamics.

  4. Transparency of intentions decreases privacy concerns in ubiquitous surveillance.

    PubMed

    Oulasvirta, Antti; Suomalainen, Tiia; Hamari, Juho; Lampinen, Airi; Karvonen, Kristiina

    2014-10-01

    An online experiment (n=1,897) was carried out to understand how data disclosure practices in ubiquitous surveillance affect users' privacy concerns. Information about the identity and intentions of a data collector was manipulated in hypothetical surveillance scenarios. Privacy concerns were found to differ across the scenarios and moderated by knowledge about the collector's identity and intentions. Knowledge about intentions exhibited a stronger effect. When no information about intentions was disclosed, the respondents postulated negative intentions. A positive effect was found for disclosing neutral intentions of an organization or unknown data collector, but not for a private data collector. The findings underline the importance of disclosing intentions of data use to users in an easily understandable manner.

  5. Exploring the Potential of Podcasting to Deliver Mobile Ubiquitous Learning in Higher Education

    ERIC Educational Resources Information Center

    Lee, Mark J. W.; Chan, Anthony

    2006-01-01

    Podcasting facilitates the timely delivery of digital audio content such as MP3 files to a user's desktop, as it becomes available. The authors believe it holds tremendous potential as a low-cost, low-barrier tool for mobile ubiquitous learning, given the large uptake of portable music players. This paper explores some of the possibilities for…

  6. An Adaptive Navigation Support System for Conducting Context-Aware Ubiquitous Learning in Museums

    ERIC Educational Resources Information Center

    Chiou, Chuang-Kai; Tseng, Judy C. R.; Hwang, Gwo-Jen; Heller, Shelly

    2010-01-01

    In context-aware ubiquitous learning, students are guided to learn in the real world with personalized supports from the learning system. As the learning resources are realistic objects in the real world, certain physical constraints, such as the limitation of stream of people who visit the same learning object, the time for moving from one object…

  7. A ubiquitous reflective e-portfolio architecture.

    PubMed

    Forte, Marcos; de Souza, Wanderley L; da Silva, Roseli F; do Prado, Antonio F; Rodrigues, Jose F

    2013-11-01

    In nurse and in medicine courses, the use of reflective portfolios as a pedagogical tool is becoming a common practice; in the last years, this practice has gradually migrated from paper-based to electronic-based portfolios. Current approaches for reflective e-portfolios, however, do not widely operate at outdoor sites, where data networks are limited or nonexistent. Considering that many of the activities related to nurse and medicine courses relate to professional practices conducted in such conditions, these network shortcomings restrict the adoption of e-portfolios. The present study describes the requirements specification, design, implementation, and evaluation of the Ubiquitous Reflective E-Portfolio Architecture, a solution proposed to support the development of systems based on mobile and wired access for both online and offline operation. We have implemented a prototype named Professional Practice Module to evaluate the Ubiquitous Reflective E-Portfolio Architecture; the module was based on requirements observed during the professional practice, the paper-based portfolio in use, and related learning meetings in the Medicine Course of a Brazilian University. The evaluation of the system was carried out with a learning group of 2nd year students of the medicine course, who answered to extensive evaluation questionnaires. The prototype proved to be operational in the activities of the professional practice of the Medicine Course object of the study, including homework tasks, patient care, data sharing, and learning meetings. It also demonstrated to be versatile with respect to the availability of the computer network that, many times, was not accessible. Moreover, the students considered the module useful and easy to use, but pointed out difficulties about the keyboard and the display sizes of the netbook devices, and about their operational system. Lastly, most of the students declared preference for the electronic Professional Practice Module in internal

  8. Wear evaluation of a cross-linked medical grade polyethylene by ultra thin layer activation compared to gravimetry

    NASA Astrophysics Data System (ADS)

    Stroosnijder, Marinus F.; Hoffmann, Michael; Sauvage, Thierry; Blondiaux, Gilbert; Vincent, Laetitia

    2005-01-01

    Most of today's artificial joints rely on an articulating couple consisting of a CoCrMo alloy and a medical grade polyethylene. The wear of the polyethylene component is the major cause for long-term failure of these prostheses since the wear debris leads to adverse biological reactions. The polyethylene wear is usually measured by gravimetric methods, which are limited due to a low sensitivity and accuracy. To demonstrate the reliability of ultra thin layer activation (UTLA) as an alternative technique, wear tests on a cross-linked ultra-high-molecular weight polyethylene (XLPE) sliding against CoCrMo were performed on a wear tester featuring multi-directional sliding motion. The amount of polyethylene wear was evaluated by both UTLA and gravimetry. The particular TLA method used in this work employed the implantation of 7Be radioactive recoils into the polyethylene surface by means of a light mass particle beam. The results indicate that apart from its relatively high sensitivity, UTLA also offers the possibility for on-line measurements of polyethylene wear. This makes it a viable and complementary technique in wear test studies for medical implant purposes especially for those involving wear resistant materials and for rapid wear screening.

  9. Application of an Externded CCSDS Telecommand Standard for All Mars In-Situ Telecommunication Links

    NASA Technical Reports Server (NTRS)

    Kazz, G.; Greenberg, E.; MacMedan, M.

    1998-01-01

    The purpose of this paper is to propose a link layer standard for bi-directional telecommunication for in-situ links for data transfer between landers, rovers, and orbiters based upon the CCSDS Telecommand Recommendation.

  10. The life history of Pseudomonas syringae: linking agriculture to earth system processes.

    PubMed

    Morris, Cindy E; Monteil, Caroline L; Berge, Odile

    2013-01-01

    The description of the ecology of Pseudomonas syringae is moving away from that of a ubiquitous epiphytic plant pathogen to one of a multifaceted bacterium sans frontières in fresh water and other ecosystems linked to the water cycle. Discovery of the aquatic facet of its ecology has led to a vision of its life history that integrates spatial and temporal scales spanning billions of years and traversing catchment basins, continents, and the planet and that confronts the implication of roles that are potentially conflicting for agriculture (as a plant pathogen and as an actor in processes leading to rain and snowfall). This new ecological perspective has also yielded insight into epidemiological phenomena linked to disease emergence. Overall, it sets the stage for the integration of more comprehensive contexts of ecology and evolutionary history into comparative genomic analyses to elucidate how P. syringae subverts the attack and defense responses of the cohabitants of the diverse environments it occupies.

  11. Stepping towards new parameterizations for non-canonical atmospheric surface-layer conditions

    NASA Astrophysics Data System (ADS)

    Calaf, M.; Margairaz, F.; Pardyjak, E.

    2017-12-01

    Representing land-atmosphere exchange processes as a lower boundary condition remains a challenge. This is partially a result of the fact that land-surface heterogeneity exists at all spatial scales and its variability does not "average" out with decreasing scales. Such variability need not rapidly blend away from the boundary thereby impacting the near-surface region of the atmosphere. Traditionally, momentum and energy fluxes linking the land surface to the flow in NWP models have been parameterized using atmospheric surface layer (ASL) similarity theory. There is ample evidence that such representation is acceptable for stationary and planar-homogeneous flows in the absence of subsidence. However, heterogeneity remains a ubiquitous feature eliciting appreciable deviations when using ASL similarity theory, especially in scalars such moisture and air temperature whose blending is less efficient when compared to momentum. The focus of this project is to quantify the effect of surface thermal heterogeneity with scales Ο(1/10) the height of the atmospheric boundary layer and characterized by uniform roughness. Such near-canonical cases describe inhomogeneous scalar transport in an otherwise planar homogeneous flow when thermal stratification is weak or absent. In this work we present a large-eddy simulation study that characterizes the effect of surface thermal heterogeneities on the atmospheric flow using the concept of dispersive fluxes. Results illustrate a regime in which the flow is mostly driven by the surface thermal heterogeneities, in which the contribution of the dispersive fluxes can account for up to 40% of the total sensible heat flux. Results also illustrate an alternative regime in which the effect of the surface thermal heterogeneities is quickly blended, and the dispersive fluxes provide instead a quantification of the flow spatial heterogeneities produced by coherent turbulent structures result of the surface shear stress. A threshold flow

  12. Ubiquitous healthy diatoms in the deep sea confirms deep carbon injection by the biological pump

    NASA Astrophysics Data System (ADS)

    Agustí, Susana; González-Gordillo, Jose I.; Vaqué, Dolors; Estrada, Marta; Cerezo, Maria I.; Salazar, Guillem; Gasol, Josep M.; Duarte, Carlos M.

    2016-04-01

    The role of the ocean as a sink for CO2 is partially dependent on the downward transport of phytoplankton cells packaged within fast-sinking particles. However, whether such fast-sinking mechanisms deliver fresh organic carbon down to the deep bathypelagic sea and whether this mechanism is prevalent across the ocean awaits confirmation. Photosynthetic plankton, directly responsible for trapping CO2 in organic form in the surface layer, are a key constituent of the flux of sinking particles and are assumed to die and become detritus upon leaving the photic layer. Research in the 1960-70's reported the occasional presence of well-preserved phytoplankton cells in the deep ocean, but these observations, which could signal at rapid sinking rates, were considered anecdotal. Using new developments we tested the presence of healthy phytoplankton cells in the deep sea (2000 to 4000 m depth) along the Malaspina 2010 Circumnavigation Expedition, a global expedition sampling the bathypelagic zone of the Atlantic, Indian and Pacific Oceans. In particular, we used a new microplankton sampling device, the Bottle-Net, 16S rDNA sequences, flow cytometric counts, vital stains and experiments to explore the abundance and health status of photosynthetic plankton cells between 2,000 and 4,000 m depth along the Circumnavigation track. We described the community of microplankton (> 20μm) found at the deep ocean (2000-4000 m depth), surprisingly dominated by phytoplankton, and within this, by diatoms. Moreover, we report the ubiquitous presence of healthy photosynthetic cells, dominated by diatoms, down to 4,000 m in the deep dark sea. Decay experiments with surface phytoplankton suggested that the large proportion (18%) of healthy photosynthetic cells observed, on average, in the dark ocean, requires transport times from few days to few weeks, corresponding to sinking rates of 124 to 732 m d-1, comparable to those of fast sinking aggregates and faecal pellets. These results confirm the

  13. Ubiquitous Geo-Sensing for Context-Aware Analysis: Exploring Relationships between Environmental and Human Dynamics

    PubMed Central

    Sagl, Günther; Blaschke, Thomas; Beinat, Euro; Resch, Bernd

    2012-01-01

    Ubiquitous geo-sensing enables context-aware analyses of physical and social phenomena, i.e., analyzing one phenomenon in the context of another. Although such context-aware analysis can potentially enable a more holistic understanding of spatio-temporal processes, it is rarely documented in the scientific literature yet. In this paper we analyzed the collective human behavior in the context of the weather. We therefore explored the complex relationships between these two spatio-temporal phenomena to provide novel insights into the dynamics of urban systems. Aggregated mobile phone data, which served as a proxy for collective human behavior, was linked with the weather data from climate stations in the case study area, the city of Udine, Northern Italy. To identify and characterize potential patterns within the weather-human relationships, we developed a hybrid approach which integrates several spatio-temporal statistical analysis methods. Thereby we show that explanatory factor analysis, when applied to a number of meteorological variables, can be used to differentiate between normal and adverse weather conditions. Further, we measured the strength of the relationship between the ‘global’ adverse weather conditions and the spatially explicit effective variations in user-generated mobile network traffic for three distinct periods using the Maximal Information Coefficient (MIC). The analyses result in three spatially referenced maps of MICs which reveal interesting insights into collective human dynamics in the context of weather, but also initiate several new scientific challenges. PMID:23012571

  14. Reactive polymer multilayers fabricated by covalent layer-by-layer assembly: 1,4-conjugate addition-based approaches to the design of functional biointerfaces.

    PubMed

    Bechler, Shane L; Lynn, David M

    2012-05-14

    We report on conjugate addition-based approaches to the covalent layer-by-layer assembly of thin films and the post-fabrication functionalization of biointerfaces. Our approach is based on a recently reported approach to the "reactive" assembly of covalently cross-linked polymer multilayers driven by the 1,4-conjugate addition of amine functionality in poly(ethyleneimine) (PEI) to the acrylate groups in a small-molecule pentacrylate species (5-Ac). This process results in films containing degradable β-amino ester cross-links and residual acrylate and amine functionality that can be used as reactive handles for the subsequent immobilization of new functionality. Layer-by-layer growth of films fabricated on silicon substrates occurred in a supra-linear manner to yield films ≈ 750 nm thick after the deposition of 80 PEI/5-Ac layers. Characterization by atomic force microscopy (AFM) suggested a mechanism of growth that involves the reactive deposition of nanometer-scale aggregates of PEI and 5-Ac during assembly. Infrared (IR) spectroscopy studies revealed covalent assembly to occur by 1,4-conjugate addition without formation of amide functionality. Additional experiments demonstrated that acrylate-containing films could be postfunctionalized via conjugate addition reactions with small-molecule amines that influence important biointerfacial properties, including water contact angles and the ability of film-coated surfaces to prevent or promote the attachment of cells in vitro. For example, whereas conjugation of the hydrophobic molecule decylamine resulted in films that supported cell adhesion and growth, films treated with the carbohydrate-based motif D-glucamine resisted cell attachment and growth almost completely for up to 7 days in serum-containing media. We demonstrate that this conjugate addition-based approach also provides a means of immobilizing functionality through labile ester linkages that can be used to promote the long-term, surface-mediated release

  15. A low-power bio-potential acquisition system with flexible PDMS dry electrodes for portable ubiquitous healthcare applications.

    PubMed

    Chen, Chih-Yuan; Chang, Chia-Lin; Chang, Chih-Wei; Lai, Shin-Chi; Chien, Tsung-Fu; Huang, Hong-Yi; Chiou, Jin-Chern; Luo, Ching-Hsing

    2013-03-04

    This work describes a bio-potential acquisition system for portable ubiquitous healthcare applications using flexible polydimethylsiloxane dry electrodes (FPDEs) and a low-power recording circuit. This novel FPDE used Au as the skin contact layer, which was made using a CO2 laser and replica method technology. The FPDE was revised from a commercial bio-potential electrode with a conductive snap using dry electrodes rather than wet electrodes that proposed reliable and robust attachment for the purpose of measurement, and attaching velcro made it wearable on the forearm for bio-potential applications. Furthermore, this study proposes a recording device to store bio-potential signal data and provides portability and low-power consumption for the proposed acquisition system. To acquire differential bio-potentials, such as electrocardiogram (ECG) signals, the proposed recording device includes a low-power front-end acquisition chip fabricated using a complementary metal-oxide-semiconductor (CMOS) process, a commercial microcontroller (MSP430F149), and a secure digital (SD) card for portable healthcare applications. The proposed system can obtain ECG signals efficiently and are comfortable to the skin. The power consumption of the system is about 85 mW for continuous working over a 3 day period with two AA batteries. It can also be used as a compact Holter ECG system.

  16. A Low-Power Bio-Potential Acquisition System with Flexible PDMS Dry Electrodes for Portable Ubiquitous Healthcare Applications

    PubMed Central

    Chen, Chih-Yuan; Chang, Chia-Lin; Chang, Chih-Wei; Lai, Shin-Chi; Chien, Tsung-Fu; Huang, Hong-Yi; Chiou, Jin-Chern; Luo, Ching-Hsing

    2013-01-01

    This work describes a bio-potential acquisition system for portable ubiquitous healthcare applications using flexible polydimethylsiloxane dry electrodes (FPDEs) and a low-power recording circuit. This novel FPDE used Au as the skin contact layer, which was made using a CO2 laser and replica method technology. The FPDE was revised from a commercial bio-potential electrode with a conductive snap using dry electrodes rather than wet electrodes that proposed reliable and robust attachment for the purpose of measurement, and attaching velcro made it wearable on the forearm for bio-potential applications. Furthermore, this study proposes a recording device to store bio-potential signal data and provides portability and low-power consumption for the proposed acquisition system. To acquire differential bio-potentials, such as electrocardiogram (ECG) signals, the proposed recording device includes a low-power front-end acquisition chip fabricated using a complementary metal-oxide-semiconductor (CMOS) process, a commercial microcontroller (MSP430F149), and a secure digital (SD) card for portable healthcare applications. The proposed system can obtain ECG signals efficiently and are comfortable to the skin. The power consumption of the system is about 85 mW for continuous working over a 3 day period with two AA batteries. It can also be used as a compact Holter ECG system. PMID:23459390

  17. Ubiquitous sialometabolism present among oral fusobacteria.

    PubMed

    Yoneda, Saori; Loeser, Brandon; Feng, Joseph; Dmytryk, John; Qi, Fengxia; Merritt, Justin

    2014-01-01

    Fusobacterium nucleatum is a ubiquitous member of the human oral flora and is associated with the development of periodontitis and a variety of other types of polymicrobial infections of the mucosa. In the oral cavity, this species is one of the few that is prevalent in both healthy and diseased subgingival plaque. Using microarray analysis, we examined the transcriptional response of F. nucleatum subspecies nucleatum to whole blood in order to identify some of the genetic responses that might occur during the transition from health to disease. From these studies, we identified a sialic acid catabolism operon that was induced by the presence of blood. We subsequently confirmed that this operon was inducible by the presence of synthetic sialic acid, but we found no evidence suggesting sialic acid was used as a major carbon source. However, this organism was found to possess a de novo synthesized surface sialylation ability that is widely conserved among the various F. nucleatum subspecies as well as in F. periodonticum. We provide evidence that fusobacterial sialylation does occur in the oral cavity irrespective of health status. Interestingly, only a minority of fusobacterial cells exhibit surface sialylation within dental plaque, whereas most cells are uniformly sialylated when grown in pure culture. The implications of these results are discussed.

  18. Publishing Data on Physical Samples Using the GeoLink Ontology and Linked Data Platforms

    NASA Astrophysics Data System (ADS)

    Ji, P.; Arko, R. A.; Lehnert, K. A.; Song, L.; Carter, M. R.; Hsu, L.

    2015-12-01

    Interdisciplinary Earth Data Alliance (IEDA), one of partners in EarthCube GeoLink project, seeks to explore the extent to which the use of GeoLink reusable Ontology Design Patterns (ODPs) and linked data platforms in IEDA data infrastructure can make research data more easily accessible and valuable. Linked data for the System for Earth Sample Registration (SESAR) is the first effort of IEDA to show how linked data enhance the presentation of IEDA data system architecture. SESAR Linked Data maps each table and column in SESAR database to RDF class and property based on GeoLink view, which build on the top of GeoLink ODPs. Then, uses D2RQ dumping the contents of SESAR database into RDF triples on the basis of mapping results. And, the dumped RDF triples is loaded into GRAPHDB, an RDF graph database, as permanent data in the form of atomic facts expressed as subjects, predicates and objects which provide support for semantic interoperability between IEDA and other GeoLink partners. Finally, an integrated browsing and searching interface build on Callimachus, a highly scalable platform for publishing linked data, is introduced to make sense of data stored in triplestore. Drill down and through features are built in the interface to help users locating content efficiently. The drill down feature enables users to explore beyond the summary information in the instance list of a specific class and into the detail from the specific instance page. The drill through feature enables users to jump from one instance to another one by simply clicking the link of the latter nested in the former region. Additionally, OpenLayers map is embedded into the interface to enhance the attractiveness of the presentation of instance which has geospatial information. Furthermore, by linking instances in the SESAR datasets to matching or corresponding instances in external sets, the presentation has been enriched with additional information about related classes like person, cruise, etc.

  19. Human Pacman: A Mobile Augmented Reality Entertainment System Based on Physical, Social, and Ubiquitous Computing

    NASA Astrophysics Data System (ADS)

    Cheok, Adrian David

    This chapter details the Human Pacman system to illuminate entertainment computing which ventures to embed the natural physical world seamlessly with a fantasy virtual playground by capitalizing on infrastructure provided by mobile computing, wireless LAN, and ubiquitous computing. With Human Pacman, we have a physical role-playing computer fantasy together with real human-social and mobile-gaming that emphasizes on collaboration and competition between players in a wide outdoor physical area that allows natural wide-area human-physical movements. Pacmen and Ghosts are now real human players in the real world experiencing mixed computer graphics fantasy-reality provided by using the wearable computers on them. Virtual cookies and actual tangible physical objects are incorporated into the game play to provide novel experiences of seamless transitions between the real and virtual worlds. This is an example of a new form of gaming that anchors on physicality, mobility, social interaction, and ubiquitous computing.

  20. UBioLab: a web-laboratory for ubiquitous in-silico experiments.

    PubMed

    Bartocci, Ezio; Cacciagrano, Diletta; Di Berardini, Maria Rita; Merelli, Emanuela; Vito, Leonardo

    2012-07-09

    The huge and dynamic amount of bioinformatic resources (e.g., data and tools) available nowadays in Internet represents a big challenge for biologists –for what concerns their management and visualization– and for bioinformaticians –for what concerns the possibility of rapidly creating and executing in-silico experiments involving resources and activities spread over the WWW hyperspace. Any framework aiming at integrating such resources as in a physical laboratory has imperatively to tackle –and possibly to handle in a transparent and uniform way– aspects concerning physical distribution, semantic heterogeneity, co-existence of different computational paradigms and, as a consequence, of different invocation interfaces (i.e., OGSA for Grid nodes, SOAP for Web Services, Java RMI for Java objects, etc.). The framework UBioLab has been just designed and developed as a prototype following the above objective. Several architectural features –as those ones of being fully Web-based and of combining domain ontologies, Semantic Web and workflow techniques– give evidence of an effort in such a direction. The integration of a semantic knowledge management system for distributed (bioinformatic) resources, a semantic-driven graphic environment for defining and monitoring ubiquitous workflows and an intelligent agent-based technology for their distributed execution allows UBioLab to be a semantic guide for bioinformaticians and biologists providing (i) a flexible environment for visualizing, organizing and inferring any (semantics and computational) "type" of domain knowledge (e.g., resources and activities, expressed in a declarative form), (ii) a powerful engine for defining and storing semantic-driven ubiquitous in-silico experiments on the domain hyperspace, as well as (iii) a transparent, automatic and distributed environment for correct experiment executions.

  1. UBioLab: a web-LABoratory for Ubiquitous in-silico experiments.

    PubMed

    Bartocci, E; Di Berardini, M R; Merelli, E; Vito, L

    2012-03-01

    The huge and dynamic amount of bioinformatic resources (e.g., data and tools) available nowadays in Internet represents a big challenge for biologists -for what concerns their management and visualization- and for bioinformaticians -for what concerns the possibility of rapidly creating and executing in-silico experiments involving resources and activities spread over the WWW hyperspace. Any framework aiming at integrating such resources as in a physical laboratory has imperatively to tackle -and possibly to handle in a transparent and uniform way- aspects concerning physical distribution, semantic heterogeneity, co-existence of different computational paradigms and, as a consequence, of different invocation interfaces (i.e., OGSA for Grid nodes, SOAP for Web Services, Java RMI for Java objects, etc.). The framework UBioLab has been just designed and developed as a prototype following the above objective. Several architectural features -as those ones of being fully Web-based and of combining domain ontologies, Semantic Web and workflow techniques- give evidence of an effort in such a direction. The integration of a semantic knowledge management system for distributed (bioinformatic) resources, a semantic-driven graphic environment for defining and monitoring ubiquitous workflows and an intelligent agent-based technology for their distributed execution allows UBioLab to be a semantic guide for bioinformaticians and biologists providing (i) a flexible environment for visualizing, organizing and inferring any (semantics and computational) "type" of domain knowledge (e.g., resources and activities, expressed in a declarative form), (ii) a powerful engine for defining and storing semantic-driven ubiquitous in-silico experiments on the domain hyperspace, as well as (iii) a transparent, automatic and distributed environment for correct experiment executions.

  2. Genomic analysis reveals a tight link between transcription factor dynamics and regulatory network architecture.

    PubMed

    Jothi, Raja; Balaji, S; Wuster, Arthur; Grochow, Joshua A; Gsponer, Jörg; Przytycka, Teresa M; Aravind, L; Babu, M Madan

    2009-01-01

    Although several studies have provided important insights into the general principles of biological networks, the link between network organization and the genome-scale dynamics of the underlying entities (genes, mRNAs, and proteins) and its role in systems behavior remain unclear. Here we show that transcription factor (TF) dynamics and regulatory network organization are tightly linked. By classifying TFs in the yeast regulatory network into three hierarchical layers (top, core, and bottom) and integrating diverse genome-scale datasets, we find that the TFs have static and dynamic properties that are similar within a layer and different across layers. At the protein level, the top-layer TFs are relatively abundant, long-lived, and noisy compared with the core- and bottom-layer TFs. Although variability in expression of top-layer TFs might confer a selective advantage, as this permits at least some members in a clonal cell population to initiate a response to changing conditions, tight regulation of the core- and bottom-layer TFs may minimize noise propagation and ensure fidelity in regulation. We propose that the interplay between network organization and TF dynamics could permit differential utilization of the same underlying network by distinct members of a clonal cell population.

  3. System Requirement Analyses for Ubiquitous Environment Management System

    NASA Astrophysics Data System (ADS)

    Lim, Sang Boem; Gil, Kyung Jun; Choe, Ho Rim; Eo, Yang Dam

    We are living in new stage of society. U-City introduces new paradigm that cannot be archived in traditional city to future city. Korea is one of the most active countries to construct U-City based on advances of IT technologies - especially based on high-speed network through out country [1]. Peoples are realizing ubiquitous service is key factor of success of U-City. Among the U-services, U-security service is one of the most important services. Nowadays we have to concern about traditional threat and also personal information. Since apartment complex is the most common residence type in Korea. We are developing security rules and system based on analyses of apartment complex and assert of apartment complex. Based on these analyses, we are developing apartment complex security using various technologies including home network system. We also will discuss basic home network security architecture.

  4. Charged particle layers in the Debye limit.

    PubMed

    Golden, Kenneth I; Kalman, Gabor J; Kyrkos, Stamatios

    2002-09-01

    We develop an equivalent of the Debye-Hückel weakly coupled equilibrium theory for layered classical charged particle systems composed of one single charged species. We consider the two most important configurations, the charged particle bilayer and the infinite superlattice. The approach is based on the link provided by the classical fluctuation-dissipation theorem between the random-phase approximation response functions and the Debye equilibrium pair correlation function. Layer-layer pair correlation functions, screened and polarization potentials, static structure functions, and static response functions are calculated. The importance of the perfect screening and compressibility sum rules in determining the overall behavior of the system, especially in the r--> infinity limit, is emphasized. The similarities and differences between the quasi-two-dimensional bilayer and the quasi-three-dimensional superlattice are highlighted. An unexpected behavior that emerges from the analysis is that the screened potential, the correlations, and the screening charges carried by the individual layers exhibit a marked nonmonotonic dependence on the layer separation.

  5. The Internal Structure of Jupiter Family Comet Nuclei: The Talps or Layered Pile Model

    NASA Astrophysics Data System (ADS)

    Belton, Michael J.; Members of theDeep Impact Science Team

    2006-09-01

    The characteristics of layered structures seen on the nucleus of Tempel 1 in the Deep Impact images, and also seen on Wild 2 and Borrelly are noted. We consider the implications of the hypothesis that such structures are ubiquitous on Jupiter Family Comets and is an essential element of their internal stucture. If correct this hypothesis implies that the internal structure of JFCs are primordial remnants of the early agglomeration phase and that the physical structure of their interiors, except for possible compositional changes, is essentially as it was when they were formed. This hypothesis has implications for their place of origin and their subsequent collisional evolution. Current models of the latter are in conflict with this hypothesis. Possible resolutions of this conflict are noted. A new conceptual model of the interior of a typical JFC called the Talps or "layered pile" model is presented.

  6. Implementation of Wireless Sensor Networks Based Pig Farm Integrated Management System in Ubiquitous Agricultural Environments

    NASA Astrophysics Data System (ADS)

    Hwang, Jeonghwan; Lee, Jiwoong; Lee, Hochul; Yoe, Hyun

    The wireless sensor networks (WSN) technology based on low power consumption is one of the important technologies in the realization of ubiquitous society. When the technology would be applied to the agricultural field, it can give big change in the existing agricultural environment such as livestock growth environment, cultivation and harvest of agricultural crops. This research paper proposes the 'Pig Farm Integrated Management System' based on WSN technology, which will establish the ubiquitous agricultural environment and improve the productivity of pig-raising farmers. The proposed system has WSN environmental sensors and CCTV at inside/outside of pig farm. These devices collect the growth-environment related information of pigs, such as luminosity, temperature, humidity and CO2 status. The system collects and monitors the environmental information and video information of pig farm. In addition to the remote-control and monitoring of the pig farm facilities, this system realizes the most optimum pig-raising environment based on the growth environmental data accumulated for a long time.

  7. Immobilized liquid layers: A new approach to anti-adhesion surfaces for medical applications

    PubMed Central

    Sotiri, Irini; Overton, Jonathan C; Waterhouse, Anna

    2016-01-01

    Surface fouling and undesired adhesion are nearly ubiquitous problems in the medical field, complicating everything from surgeries to routine daily care of patients. Recently, the concept of immobilized liquid (IL) interfaces has been gaining attention as a highly versatile new approach to antifouling, with a wide variety of promising applications in medicine. Here, we review the general concepts behind IL layers and discuss the fabrication strategies on medically relevant materials developed so far. We also summarize the most important findings to date on applications of potential interest to the medical community, including the use of these surfaces as anti-thrombogenic and anti-bacterial materials, anti-adhesive textiles, high-performance coatings for optics, and as unique platforms for diagnostics. Although the full potential and pitfalls of IL layers in medicine are just beginning to be explored, we believe that this approach to anti-adhesive surfaces will prove broadly useful for medical applications in the future. PMID:27022136

  8. Successful enrichment of the ubiquitous freshwater acI Actinobacteria.

    PubMed

    Garcia, Sarahi L; McMahon, Katherine D; Grossart, Hans-Peter; Warnecke, Falk

    2014-02-01

    Actinobacteria of the acI lineage are often the numerically dominant bacterial phylum in surface freshwaters, where they can account for > 50% of total bacteria. Despite their abundance, there are no described isolates. In an effort to obtain enrichment of these ubiquitous freshwater Actinobacteria, diluted freshwater samples from Lake Grosse Fuchskuhle, Germany, were incubated in 96-well culture plates. With this method, a successful enrichment containing high abundances of a member of the lineage acI was established. Phylogenetic classification showed that the acI Actinobacteria of the enrichment belonged to the acI-B2 tribe, which seems to prefer acidic lakes. This enrichment grows to low cell densities and thus the oligotrophic nature of acI-B2 was confirmed. © 2013 Society for Applied Microbiology and John Wiley & Sons Ltd.

  9. Optimizing diffusion in multiplexes by maximizing layer dissimilarity

    NASA Astrophysics Data System (ADS)

    Serrano, Alfredo B.; Gómez-Gardeñes, Jesús; Andrade, Roberto F. S.

    2017-05-01

    Diffusion in a multiplex depends on the specific link distribution between the nodes in each layer, but also on the set of the intralayer and interlayer diffusion coefficients. In this work we investigate, in a quantitative way, the efficiency of multiplex diffusion as a function of the topological similarity among multiplex layers. This similarity is measured by the distance between layers, taken among the pairs of layers. Results are presented for a simple two-layer multiplex, where one of the layers is held fixed, while the other one can be rewired in a controlled way in order to increase or decrease the interlayer distance. The results indicate that, for fixed values of all intra- and interlayer diffusion coefficients, a large interlayer distance generally enhances the global multiplex diffusion, providing a topological mechanism to control the global diffusive process. For some sets of networks, we develop an algorithm to identify the most sensitive nodes in the rewirable layer, so that changes in a small set of connections produce a drastic enhancement of the global diffusion of the whole multiplex system.

  10. Quasistatic Cavity Resonance for Ubiquitous Wireless Power Transfer.

    PubMed

    Chabalko, Matthew J; Shahmohammadi, Mohsen; Sample, Alanson P

    2017-01-01

    Wireless power delivery has the potential to seamlessly power our electrical devices as easily as data is transmitted through the air. However, existing solutions are limited to near contact distances and do not provide the geometric freedom to enable automatic and un-aided charging. We introduce quasistatic cavity resonance (QSCR), which can enable purpose-built structures, such as cabinets, rooms, and warehouses, to generate quasistatic magnetic fields that safely deliver kilowatts of power to mobile receivers contained nearly anywhere within. A theoretical model of a quasistatic cavity resonator is derived, and field distributions along with power transfer efficiency are validated against measured results. An experimental demonstration shows that a 54 m3 QSCR room can deliver power to small coil receivers in nearly any position with 40% to 95% efficiency. Finally, a detailed safety analysis shows that up to 1900 watts can be transmitted to a coil receiver enabling safe and ubiquitous wireless power.

  11. Quasistatic Cavity Resonance for Ubiquitous Wireless Power Transfer

    PubMed Central

    Shahmohammadi, Mohsen; Sample, Alanson P.

    2017-01-01

    Wireless power delivery has the potential to seamlessly power our electrical devices as easily as data is transmitted through the air. However, existing solutions are limited to near contact distances and do not provide the geometric freedom to enable automatic and un-aided charging. We introduce quasistatic cavity resonance (QSCR), which can enable purpose-built structures, such as cabinets, rooms, and warehouses, to generate quasistatic magnetic fields that safely deliver kilowatts of power to mobile receivers contained nearly anywhere within. A theoretical model of a quasistatic cavity resonator is derived, and field distributions along with power transfer efficiency are validated against measured results. An experimental demonstration shows that a 54 m3 QSCR room can deliver power to small coil receivers in nearly any position with 40% to 95% efficiency. Finally, a detailed safety analysis shows that up to 1900 watts can be transmitted to a coil receiver enabling safe and ubiquitous wireless power. PMID:28199321

  12. Investigation of sacrificial layer and building block for layered nanofabrication (LNF)

    NASA Astrophysics Data System (ADS)

    Shih, Ting-Yu

    Layered Nanoscale Fabrication (LNF) is a "bottom-up" procedure that uses multiple layers to build 3-dimensional nanoscale structures. Here, in this dissertation, several candidates for sacrificial layers were explored, The thermal stability of gold nanoparticles and simple patterns are also reported. In order to obtain information on layer thickness and film quality; the samples were characterized using atomic force microscopy (AFM) and ellipsometry. Octadecyltrichlorosilane (OTS) was first investigated for use as a sacrificial layer and we studied filth growth by targeted self-replication of silane multilayers with and without the presence of thiolated gold nanoparticles on silicon oxide substrates. The particles adhered to the substrate during layer grafting. The film grew selectively on the substrate, without covering the particles. AFM was used to investigate the growth mechanism and the process of embedding the nanoparticles. OTS multilayer films up to 9 layers were grown in a linear, bilayer-by bilayer mode, free of islands and defects. We also report on studies of monolayer and multilayer formation of Methyl-11-dimethylmonochlorosilyl-undecanoate films. Flat multilayers up to 3-layers thick were grown. AFM was used to measure the height of an observable "edge" of the multilayer film and this provides and independent determination of the MOSUD layer height of 1.5 nm: However, the particles detached from the surface when we attempted to grow multilayer. One strategy of linking the particles to form 2D arrays, thermal activation in ambient air, was investigated. The morphological properties of flaked nanoparticles and structures on silicon oxide substrates before and after heating were characterized by using AFM. For widely separated 5 nm gold nanoparticles height decreased over 50% at 600 °C. Further heating to 630 °C caused most particles to completely disappear, with small amount of particle residue left on the surface. Particles positioned near to other

  13. Identification of rat Rosa26 locus enables generation of knock-in rat lines ubiquitously expressing tdTomato.

    PubMed

    Kobayashi, Toshihiro; Kato-Itoh, Megumi; Yamaguchi, Tomoyuki; Tamura, Chihiro; Sanbo, Makoto; Hirabayashi, Masumi; Nakauchi, Hiromitsu

    2012-11-01

    Recent discovery of a method for derivation and culture of germline-competent rat pluripotent stem cells (PSCs) enables generation of transgenic rats or knock-out rats via genetic modification of such PSCs. This opens the way to use rats, as is routine in mice, for analyses of gene functions or physiological features. In mouse or human, one widely used technique to express a gene of interest stably and ubiquitously is to insert that gene into the Rosa26 locus via gene targeting of PSCs. Rosa26 knock-in mice conditionally expressing a reporter or a toxin gene have contributed to tracing or ablation of specific cell lineages. We successfully identified a rat orthologue of the mouse Rosa26 locus. Insertion of tdTomato, a variant of red fluorescent protein, into the Rosa26 locus of PSCs of various rat strains allows ubiquitous expression of tdTomato. Through germline transmission of one Rosa26-tdTomato knock-in embryonic stem cell line, we also obtained tdTomato knock-in rats. These expressed tdTomato ubiquitously throughout their bodies, which indicates that the rat Rosa26 locus conserves functions of its orthologues in mouse and human. The new tools described here (targeting vectors, knock-in PSCs, and rats) should be useful for a variety of research using rats.

  14. UBIQUITOUS POLLUTION FROM HEALTH AND COSMETIC ...

    EPA Pesticide Factsheets

    Those chemical pollutants that are regulated under various international, federal, and state programs represent but a small fraction of the universe of chemicals that occur in the environment as a result of both natural processses and human influence. Although this galaxy of targeted chemicals might be miniuscule compared with the universe of both known and yet-to-be identified chemicals, an implicit assumption is that these selective lists of chemicals are responsible for the most significant share of risk with respect to environmental or economic impairment or to human health.Pharmaceuticals and person care products (PPCPs) comprise a particularly large and diverse array of unregulated pollutants that occur in the environment from the combined activities and actions of multitudes of individuals as well as from veterinary and agricultural use. Although the concentration of any individual PPCP are generally less than ppt-ppb), evidence is accumulateing that these trace-level pollutants are ubiquitous, they can have a continuous presence regardless of environment half-lives (especially where sanitary wastewaters enter the environment), and the numbers of distinct and varied chemical entities could be extremely large (given that thousands are in commerical use). The research focused on in the subtasks is the development and application of state-of the-art technologies to meet the needs of the public, Office of Water, and ORD in the area of Water Quality. Locat

  15. Cross-layer Joint Relay Selection and Power Allocation Scheme for Cooperative Relaying System

    NASA Astrophysics Data System (ADS)

    Zhi, Hui; He, Mengmeng; Wang, Feiyue; Huang, Ziju

    2018-03-01

    A novel cross-layer joint relay selection and power allocation (CL-JRSPA) scheme over physical layer and data-link layer is proposed for cooperative relaying system in this paper. Our goal is finding the optimal relay selection and power allocation scheme to maximize system achievable rate when satisfying total transmit power constraint in physical layer and statistical delay quality-of-service (QoS) demand in data-link layer. Using the concept of effective capacity (EC), our goal can be formulated into an optimal joint relay selection and power allocation (JRSPA) problem to maximize the EC when satisfying total transmit power limitation. We first solving optimal power allocation (PA) problem with Lagrange multiplier approach, and then solving optimal relay selection (RS) problem. Simulation results demonstrate that CL-JRSPA scheme gets larger EC than other schemes when satisfying delay QoS demand. In addition, the proposed CL-JRSPA scheme achieves the maximal EC when relay located approximately halfway between source and destination, and EC becomes smaller when the QoS exponent becomes larger.

  16. Evaluating and Measuring How New Technologies and Ubiquitous Connectivity Affect University Students' Psychosocial Wellbeing

    ERIC Educational Resources Information Center

    Taylor, J.; Salvagno, M.; Morris, R.; Hutchings, M.; Bobeva, M.

    2018-01-01

    Where universities focus on the benefits of technology-enhanced learning (TEL), they tend to underestimate the impact on learners' experiences and wellbeing. The goal of the research reported in this article was to investigate how new technologies and ubiquitous connectivity affect students' day-to-day life, learning habits and consequent…

  17. Automated Construction of Node Software Using Attributes in a Ubiquitous Sensor Network Environment

    PubMed Central

    Lee, Woojin; Kim, Juil; Kang, JangMook

    2010-01-01

    In sensor networks, nodes must often operate in a demanding environment facing restrictions such as restricted computing resources, unreliable wireless communication and power shortages. Such factors make the development of ubiquitous sensor network (USN) applications challenging. To help developers construct a large amount of node software for sensor network applications easily and rapidly, this paper proposes an approach to the automated construction of node software for USN applications using attributes. In the proposed technique, application construction proceeds by first developing a model for the sensor network and then designing node software by setting the values of the predefined attributes. After that, the sensor network model and the design of node software are verified. The final source codes of the node software are automatically generated from the sensor network model. We illustrate the efficiency of the proposed technique by using a gas/light monitoring application through a case study of a Gas and Light Monitoring System based on the Nano-Qplus operating system. We evaluate the technique using a quantitative metric—the memory size of execution code for node software. Using the proposed approach, developers are able to easily construct sensor network applications and rapidly generate a large number of node softwares at a time in a ubiquitous sensor network environment. PMID:22163678

  18. Automated construction of node software using attributes in a ubiquitous sensor network environment.

    PubMed

    Lee, Woojin; Kim, Juil; Kang, JangMook

    2010-01-01

    In sensor networks, nodes must often operate in a demanding environment facing restrictions such as restricted computing resources, unreliable wireless communication and power shortages. Such factors make the development of ubiquitous sensor network (USN) applications challenging. To help developers construct a large amount of node software for sensor network applications easily and rapidly, this paper proposes an approach to the automated construction of node software for USN applications using attributes. In the proposed technique, application construction proceeds by first developing a model for the sensor network and then designing node software by setting the values of the predefined attributes. After that, the sensor network model and the design of node software are verified. The final source codes of the node software are automatically generated from the sensor network model. We illustrate the efficiency of the proposed technique by using a gas/light monitoring application through a case study of a Gas and Light Monitoring System based on the Nano-Qplus operating system. We evaluate the technique using a quantitative metric-the memory size of execution code for node software. Using the proposed approach, developers are able to easily construct sensor network applications and rapidly generate a large number of node softwares at a time in a ubiquitous sensor network environment.

  19. Ubiquitous Emergency Medical Service System Based on Wireless Biosensors, Traffic Information, and Wireless Communication Technologies: Development and Evaluation

    PubMed Central

    Tan, Tan-Hsu; Gochoo, Munkhjargal; Chen, Yung-Fu; Hu, Jin-Jia; Chiang, John Y.; Chang, Ching-Su; Lee, Ming-Huei; Hsu, Yung-Nian; Hsu, Jiin-Chyr

    2017-01-01

    This study presents a new ubiquitous emergency medical service system (UEMS) that consists of a ubiquitous tele-diagnosis interface and a traffic guiding subsystem. The UEMS addresses unresolved issues of emergency medical services by managing the sensor wires for eliminating inconvenience for both patients and paramedics in an ambulance, providing ubiquitous accessibility of patients’ biosignals in remote areas where the ambulance cannot arrive directly, and offering availability of real-time traffic information which can make the ambulance reach the destination within the shortest time. In the proposed system, patient’s biosignals and real-time video, acquired by wireless biosensors and a webcam, can be simultaneously transmitted to an emergency room for pre-hospital treatment via WiMax/3.5 G networks. Performances of WiMax and 3.5 G, in terms of initialization time, data rate, and average end-to-end delay are evaluated and compared. A driver can choose the route of the shortest time among the suggested routes by Google Maps after inspecting the current traffic conditions based on real-time CCTV camera streams and traffic information. The destination address can be inputted vocally for easiness and safety in driving. A series of field test results validates the feasibility of the proposed system for application in real-life scenarios. PMID:28117724

  20. Ubiquitous Emergency Medical Service System Based on Wireless Biosensors, Traffic Information, and Wireless Communication Technologies: Development and Evaluation.

    PubMed

    Tan, Tan-Hsu; Gochoo, Munkhjargal; Chen, Yung-Fu; Hu, Jin-Jia; Chiang, John Y; Chang, Ching-Su; Lee, Ming-Huei; Hsu, Yung-Nian; Hsu, Jiin-Chyr

    2017-01-21

    This study presents a new ubiquitous emergency medical service system (UEMS) that consists of a ubiquitous tele-diagnosis interface and a traffic guiding subsystem. The UEMS addresses unresolved issues of emergency medical services by managing the sensor wires for eliminating inconvenience for both patients and paramedics in an ambulance, providing ubiquitous accessibility of patients' biosignals in remote areas where the ambulance cannot arrive directly, and offering availability of real-time traffic information which can make the ambulance reach the destination within the shortest time. In the proposed system, patient's biosignals and real-time video, acquired by wireless biosensors and a webcam, can be simultaneously transmitted to an emergency room for pre-hospital treatment via WiMax/3.5 G networks. Performances of WiMax and 3.5 G, in terms of initialization time, data rate, and average end-to-end delay are evaluated and compared. A driver can choose the route of the shortest time among the suggested routes by Google Maps after inspecting the current traffic conditions based on real-time CCTV camera streams and traffic information. The destination address can be inputted vocally for easiness and safety in driving. A series of field test results validates the feasibility of the proposed system for application in real-life scenarios.

  1. Subsurface phytoplankton layers in the Arctic Ocean

    NASA Astrophysics Data System (ADS)

    Tremblay, J. E.

    2016-02-01

    Recent observations underscored the near-ubiquitous presence of subsurface chlorophyll maxima (SCM) and their potential importance for total primary production (PP) and pelagic food webs in perennially stratified waters of the Arctic Ocean. The contribution of SCM layers to annual PP is particularly important in oligotrophic areas, where modest nutrient supply to the upper euphotic zone results in weak or short-lived phytoplankton blooms near the surface. The large amount of nutrients present in the Pacific halocline relative to comparable depths in the Atlantic sector of the Arctic may also foster particularly productive SCM along the path of Pacific water. The association between strongly stratified conditions and the SCM in today's Arctic Ocean has broad relevance in providing a glimpse into the future of other oceans whose vertical stratification progressively rises with water temperature and freshwater content. In this regard, there is much to learn on the photosynthetic and nutritive ecology of SCM layers, whose biogeochemical significance depends on the extent to which they rely on allochthonous nitrogen (new production), their contribution to carbon biomass and their ability to influence air-sea CO2 exchange. Here we report on several years of eco-physiological investigations of SCM across the Arctic Ocean, with an aim to provide a basis of comparison with the ecology of SCM in other ocean areas.

  2. Low-frequency electronic noise in single-layer MoS2 transistors.

    PubMed

    Sangwan, Vinod K; Arnold, Heather N; Jariwala, Deep; Marks, Tobin J; Lauhon, Lincoln J; Hersam, Mark C

    2013-09-11

    Ubiquitous low-frequency 1/f noise can be a limiting factor in the performance and application of nanoscale devices. Here, we quantitatively investigate low-frequency electronic noise in single-layer transition metal dichalcogenide MoS2 field-effect transistors. The measured 1/f noise can be explained by an empirical formulation of mobility fluctuations with the Hooge parameter ranging between 0.005 and 2.0 in vacuum (<10(-5) Torr). The field-effect mobility decreased, and the noise amplitude increased by an order of magnitude in ambient conditions, revealing the significant influence of atmospheric adsorbates on charge transport. In addition, single Lorentzian generation-recombination noise was observed to increase by an order of magnitude as the devices were cooled from 300 to 6.5 K.

  3. Reverse-feeding effect of epidemic by propagators in two-layered networks

    NASA Astrophysics Data System (ADS)

    Dayu, Wu; Yanping, Zhao; Muhua, Zheng; Jie, Zhou; Zonghua, Liu

    2016-02-01

    Epidemic spreading has been studied for a long time and is currently focused on the spreading of multiple pathogens, especially in multiplex networks. However, little attention has been paid to the case where the mutual influence between different pathogens comes from a fraction of epidemic propagators, such as bisexual people in two separated groups of heterosexual and homosexual people. We here study this topic by presenting a network model of two layers connected by impulsive links, in contrast to the persistent links in each layer. We let each layer have a distinct pathogen and their interactive infection is implemented by a fraction of propagators jumping between the corresponding pairs of nodes in the two layers. By this model we show that (i) the propagators take the key role to transmit pathogens from one layer to the other, which significantly influences the stabilized epidemics; (ii) the epidemic thresholds will be changed by the propagators; and (iii) a reverse-feeding effect can be expected when the infective rate is smaller than its threshold of isolated spreading. A theoretical analysis is presented to explain the numerical results. Project supported by the National Natural Science Foundation of China (Grant Nos. 11135001, 11375066, and 11405059) and the National Basic Key Program of China (Grant No. 2013CB834100).

  4. Wireless communication link for capsule endoscope at 600 MHz.

    PubMed

    Khaleghi, A; Balasingham, I

    2015-01-01

    Simulation of a wireless communication link for a capsule endoscopy is presented for monitoring of small intestine in humans. The realized communication link includes the transmitting capsule antenna, the outside body receiving antenna and the model of the human body. The capsule antenna is designed for operating at the frequency band of 600 MHz with an impedance bandwidth of 10 MHz and omnidirectional radiation pattern. The quality of the communication link is improved by using directive antenna outside body inside matching layer for electromagnetic wave tuning to the body. The outside body antenna has circular polarization that guaranteeing the communication link for different orientations of the capsule inside intestine. It is shown that the path loss for the capsule in 60 mm from the abdomen surface varies between 37-47 dB in relation to the antenna orientation. This link can establish high data rate wireless communications for capsule endoscopy.

  5. A streptavidin linker layer that functions after drying.

    PubMed

    Xia, Nan; Shumaker-Parry, Jennifer S; Zareie, M Hadi; Campbell, Charles T; Castner, David G

    2004-04-27

    The ability of streptavidin (SA) to simultaneously bind four biotins is often used in linker layers, where a biotinylated molecule is linked to a biotin-functionalized surface via SA. For biosensor and array applications, it is desirable that the SA linker layer be stable to drying and rehydration. In this study it was observed that a significant decrease in binding capacity of a SA layer occurred when that layer was dried. For this study a SA linker layer was constructed by binding SA to a biotin-containing alkylthiolate monolayer (BAT/OEG) self-assembled onto gold. Its stability after drying was investigated using surface plasmon resonance (SPR). Approximately a quarter of the SA layer was removed from the BAT/OEG surface upon drying and rehydration, suggesting disruption of SA-biotin binding when dry. This resulted in the dried SA layer losing approximately 40% of its biotinylated ferritin (BF) binding capacity. Coating the layer with trehalose before drying was found to inhibit the loss of SA from the BAT/OEG surface. SPR showed that the trehalose-protected SA linker layer retained approximately 91% of its original BF binding capacity after drying and rehydration. Atomic force microscopy, which was used to image individual surface-bound SA and BF molecules, qualitatively confirmed these observations.

  6. Dependence of nanomechanical modification of polymers on plasma-induced cross-linking

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tajima, S.; Komvopoulos, K.

    2007-01-01

    The nanomechanical properties of low-density polyethylene (LDPE) modified by inductively coupled, radio-frequency Ar plasma were investigated by surface force microscopy. The polymer surface was modified under plasma conditions of different ion energy fluences and radiation intensities obtained by varying the sample distance from the plasma power source. Nanoindentation results of the surface stiffness versus maximum penetration depth did not reveal discernible differences between untreated and plasma-treated LDPE, presumably due to the small thickness of the modified surface layer that resulted in a substrate effect. On the contrary, nanoscratching experiments demonstrated a significant increase in the surface shear resistance of plasma-modifiedmore » LDPE due to chain cross-linking. These experiments revealed an enhancement of cross-linking with increasing ion energy fluence and radiation intensity, and a tip size effect on the friction force and dominant friction mechanisms (adhesion, plowing, and microcutting). In addition, LDPE samples with a LiF crystal shield were exposed to identical plasma conditions to determine the role of vacuum ultraviolet (VUV) and ultraviolet (UV) radiation in the cross-linking process. The cross-linked layer of plasma-treated LDPE exhibited much higher shear strength than that of VUV/UV-treated LDPE. Plasma-induced surface modification of the nanomechanical properties of LDPE is interpreted in the context of molecular models of the untreated and cross-linked polymer surfaces derived from experimental findings.« less

  7. The ubiquitous presence of exopolygalacturonase in maize suggests a fundamental cellular function for this enzyme.

    PubMed

    Dubald, M; Barakate, A; Mandaron, P; Mache, R

    1993-11-01

    Exopolygalacturonase (exoPG) is a pectin-degrading enzyme abundant in maize pollen. Using immunochemistry and in situ hybridization it is shown that in addition to its presence in pollen, exoPG is also present in sporophytic tissues, such as the tapetum and mesophyll cells. The enzyme is located in the cytoplasm of pollen and of some mesophyll cells. In other mesophyll cells, the tapetum and the pollen tube, exoPG is located in the cell wall. The measurement of enzyme activity shows that exoPG is ubiquitous in the vegetative organs. These results suggest a general function for exoPG in cell wall edification or degradation. ExoPG is encoded by a closely related multigene family. The regulation of the expression of one of the exoPG genes was analyzed in transgenic tobacco. Reporter GUS activity was detected in anthers, seeds and stems but not in leaves or roots of transgenic plants. This strongly suggests that the ubiquitous presence of exoPG in maize is the result of the expression of different exoPG genes.

  8. Ubiquitous and ambient-assisted living eHealth platforms for Down's syndrome and palliative care in the Republic of Panama: A systematic review.

    PubMed

    Saldaña Barrios, Juan Jose; Mendoza, Luis; Pitti, Edgardo; Vargas, Miguel

    2016-10-21

    In this work, the authors present two eHealth platforms that are examples of how health systems are migrating from client-server architecture to the web-based and ubiquitous paradigm. These two platforms were modeled, designed, developed and implemented with positive results. First, using ambient-assisted living and ubiquitous computing, the authors enhance how palliative care is being provided to the elderly patients and patients with terminal illness, making the work of doctors, nurses and other health actors easier. Second, applying machine learning methods and a data-centered, ubiquitous, patient's results' repository, the authors intent to improve the Down's syndrome risk estimation process with more accurate predictions based on local woman patients' parameters. These two eHealth platforms can improve the quality of life, not only physically but also psychologically, of the patients and their families in the country of Panama. © The Author(s) 2016.

  9. An intelligent anti-jamming network system of data link

    NASA Astrophysics Data System (ADS)

    Fan, Xiangrui; Lin, Jingyong; Liu, Jiarun; Zhou, Chunmei

    2017-10-01

    Data link is the key information system for the cooperation of weapons, single physical layer anti-jamming technology has been unable to meet its requirements. High dynamic precision-guided weapon nodes like missiles, anti-jamming design of data link system need to have stronger pertinence and effectiveness: the best anti-jamming communication mode can be selected intelligently in combat environment, in real time, guarantee the continuity of communication. We discuss an anti-jamming intelligent networking technology of data link based on interference awareness, put forward a model of intelligent anti-jamming system, and introduces the cognitive node protocol stack model and intelligent anti-jamming method, in order to improve the data chain of intelligent anti-jamming ability.

  10. An energy-efficient communication method based on the relationships between biological signals for ubiquitous health monitoring.

    PubMed

    Kwon, Hyok Chon; Na, Doosu; Ko, Byung Geun; Lee, Songjun

    2008-01-01

    Wireless sensor networks have been studied in the area of intelligent transportation systems, disaster perception, environment monitoring, ubiquitous healthcare, home network, and so on. For the ubiquitous healthcare, the previous systems collect the sensed health related data at portable devices without regard to correlations of various biological signals to determine the health conditions. It is not the energy-efficient method to gather a lot of information into a specific node to decide the health condition. Since the biological signals are related with each other to estimate certain body condition, it is necessary to be collected selectively by their relationship for energy efficiency of the networked nodes. One of researches about low power consumption is the reduction of the amount of packet transmission. In this paper, a health monitoring system, which allows the transmission of the reduced number of packets by means of setting the routing path considered the relations of biological signals, is proposed.

  11. Ubiquitous monitoring of electrical household appliances.

    PubMed

    Lloret, Jaime; Macías, Elsa; Suárez, Alvaro; Lacuesta, Raquel

    2012-11-07

    The number of appliances at home is increasing continuously, mainly because they make our lives easier. Currently, technology is integrated in all objects of our daily life. TCP/IP let us monitor our home in real time and check ubiquitously if something is happening at home. Bearing in mind this idea, we have developed a low-cost system, which can be used in any type of electrical household appliance that takes information from the appliance and posts the information to the Twitter Social network. Several sensors placed in the household appliances gather the sensed data and send them wired or wirelessly, depending on the case, using small and cheap devices to a gateway located in the home. This gateway takes decisions, based on the received data, and sends notifications to Twitter. We have developed a software application that takes the values and decides when to issue an alarm to the registered users (Twitter friends of our smart home). The performance of our system has been measured taking into account the home network (using IEEE 802.3u and IEEE 802.11g) and the data publishing in Twitter. As a result, we have generated an original product and service for any electrical household appliance, regardless of the model and manufacturer, that helps home users improve their quality of life. The paper also shows that there is no system with the same innovative features like the ones presented in this paper.

  12. Ubiquitous Monitoring of Electrical Household Appliances

    PubMed Central

    Lloret, Jaime; Macías, Elsa; Suárez, Alvaro; Lacuesta, Raquel

    2012-01-01

    The number of appliances at home is increasing continuously, mainly because they make our lives easier. Currently, technology is integrated in all objects of our daily life. TCP/IP let us monitor our home in real time and check ubiquitously if something is happening at home. Bearing in mind this idea, we have developed a low-cost system, which can be used in any type of electrical household appliance that takes information from the appliance and posts the information to the Twitter Social network. Several sensors placed in the household appliances gather the sensed data and send them wired or wirelessly, depending on the case, using small and cheap devices to a gateway located in the home. This gateway takes decisions, based on the received data, and sends notifications to Twitter. We have developed a software application that takes the values and decides when to issue an alarm to the registered users (Twitter friends of our smart home). The performance of our system has been measured taking into account the home network (using IEEE 802.3u and IEEE 802.11g) and the data publishing in Twitter. As a result, we have generated an original product and service for any electrical household appliance, regardless of the model and manufacturer, that helps home users improve their quality of life. The paper also shows that there is no system with the same innovative features like the ones presented in this paper. PMID:23202205

  13. Influence of cross-link structure, density and mechanical properties in the mesoscale deformation mechanisms of collagen fibrils

    PubMed Central

    Depalle, Baptiste; Qin, Zhao; Shefelbine, Sandra J.; Buehler, Markus J.

    2015-01-01

    Collagen is a ubiquitous protein with remarkable mechanical properties. It is highly elastic, shows large fracture strength and enables substantial energy dissipation during deformation. Most of the connective tissue in humans consists of collagen fibrils composed of a staggered array of tropocollagen molecules, which are connected by intermolecular cross-links. In this study, we report a three-dimensional coarse-grained model of collagen and analyze the influence of enzymatic cross-links on the mechanics of collagen fibrils. Two representatives immature and mature cross-links are implemented in the mesoscale model using a bottom-up approach. By varying the number, type and mechanical properties of cross-links in the fibrils and performing tensile test on the models, we systematically investigate the deformation mechanisms of cross-linked collagen fibrils. We find that cross-linked fibrils exhibit a three phase behavior, which agrees closer with experimental results than what was obtained using previous models. The fibril mechanical response is characterized by: (i) an initial elastic deformation corresponding to the collagen molecule uncoiling, (ii) a linear regime dominated by molecule sliding and (iii) the second stiffer elastic regime related to the stretching of the backbone of the tropocollagen molecules until the fibril ruptures. Our results suggest that both cross-link density and type dictate the stiffness of large deformation regime by increasing the number of interconnected molecules while cross-links mechanical properties determine the failure strain and strength of the fibril. These findings reveal that cross-links play an essential role in creating an interconnected fibrillar material of tunable toughness and strength. PMID:25153614

  14. A Context-Aware Ubiquitous Learning Approach for Providing Instant Learning Support in Personal Computer Assembly Activities

    ERIC Educational Resources Information Center

    Hsu, Ching-Kun; Hwang, Gwo-Jen

    2014-01-01

    Personal computer assembly courses have been recognized as being essential in helping students understand computer structure as well as the functionality of each computer component. In this study, a context-aware ubiquitous learning approach is proposed for providing instant assistance to individual students in the learning activity of a…

  15. A Performance Evaluation of NACK-Oriented Protocols as the Foundation of Reliable Delay- Tolerant Networking Convergence Layers

    NASA Technical Reports Server (NTRS)

    Iannicca, Dennis; Hylton, Alan; Ishac, Joseph

    2012-01-01

    Delay-Tolerant Networking (DTN) is an active area of research in the space communications community. DTN uses a standard layered approach with the Bundle Protocol operating on top of transport layer protocols known as convergence layers that actually transmit the data between nodes. Several different common transport layer protocols have been implemented as convergence layers in DTN implementations including User Datagram Protocol (UDP), Transmission Control Protocol (TCP), and Licklider Transmission Protocol (LTP). The purpose of this paper is to evaluate several stand-alone implementations of negative-acknowledgment based transport layer protocols to determine how they perform in a variety of different link conditions. The transport protocols chosen for this evaluation include Consultative Committee for Space Data Systems (CCSDS) File Delivery Protocol (CFDP), Licklider Transmission Protocol (LTP), NACK-Oriented Reliable Multicast (NORM), and Saratoga. The test parameters that the protocols were subjected to are characteristic of common communications links ranging from terrestrial to cis-lunar and apply different levels of delay, line rate, and error.

  16. Laterality strength is linked to stress reactivity in Port Jackson sharks (Heterodontus portusjacksoni).

    PubMed

    Byrnes, Evan E; Vila Pouca, Catarina; Brown, Culum

    2016-05-15

    Cerebral lateralization is an evolutionarily deep-rooted trait, ubiquitous among the vertebrates and present even in some invertebrates. Despite the advantages of cerebral lateralization in enhancing cognition and facilitating greater social cohesion, large within population laterality variation exists in many animal species. It is proposed that this variation is maintained due links with inter-individual personality trait differences. Here we explored for lateralization in Port Jackson sharks (Heterodontus portusjacksoni) using T-maze turn and rotational swimming tasks. Additionally, we explored for a link between personality traits, boldness and stress reactivity, and cerebral lateralization. Sharks demonstrated large individual and sex biased laterality variation, with females demonstrating greater lateralization than males overall. Stress reactivity, but not boldness, was found to significantly correlate with lateralization strength. Stronger lateralized individuals were more reactive to stress. Demonstrating laterality in elasmobranchs for the first time indicates ancient evolutionary roots of vertebrate lateralization approximately 240 million years old. Greater lateralization in female elasmobranchs may be related enhancing females' ability to process multiple stimuli during mating, which could increase survivability and facilitate insemination. Despite contrasting evidence in teleost fishes, the results of this study suggest that stress reactivity, and other personality traits, may be linked to variation in lateralization. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Interactions between solidification and compositional convection in mushy layers

    NASA Technical Reports Server (NTRS)

    Worster, M. Grae

    1994-01-01

    Mushy layers are ubiquitous during the solidification of alloys. They are regions of mixed phase wherein solid crystals are bathed in the melt from which they grew. The matrix of crystals forms a porous medium through which the melt can flow, driven either by external forces or by its own buoyancy in a gravitational field. Buoyancy-driven convection of the melt depends both on temperature gradients, which are necessary for solidification, and on compositional gradients, which are generated as certain components of the alloy are preferentially incorporated in the solid phase and the remaining components are expelled into the melt. In fully liquid regions, the combined action of temperature and concentration on the density of the liquid can cause various forms of double-diffusive convection. However, in the interior of mushy regions the temperature and concentration are thermodynamically coupled so only single-diffusive convection can occur. Typically, the effect of composition on the buoyancy of the melt is much greater than the effect of temperature, and thus convection in mushy layers in driven primarily by the computational gradients within them. The rising interstitial liquid is relatively dilute, having come from colder regions of the mushy layer, where the liquidus concentration is lower, and can dissolve the crystal matrix through which it flows. This is the fundamental process by which chimneys are formed. It is a nonlinear process that requires the convective velocities to be sufficiently large, so fully fledged chimneys (narrow channels) might be avoided by means that weaken the flow. Better still would be to prevent convection altogether, since even weak convection will cause lateral, compositional inhomogeneities in castings. This report outlines three studies that examine the onset of convection within mushy layers.

  18. Fixed-rate layered multicast congestion control

    NASA Astrophysics Data System (ADS)

    Bing, Zhang; Bing, Yuan; Zengji, Liu

    2006-10-01

    A new fixed-rate layered multicast congestion control algorithm called FLMCC is proposed. The sender of a multicast session transmits data packets at a fixed rate on each layer, while receivers each obtain different throughput by cumulatively subscribing to deferent number of layers based on their expected rates. In order to provide TCP-friendliness and estimate the expected rate accurately, a window-based mechanism implemented at receivers is presented. To achieve this, each receiver maintains a congestion window, adjusts it based on the GAIMD algorithm, and from the congestion window an expected rate is calculated. To measure RTT, a new method is presented which combines an accurate measurement with a rough estimation. A feedback suppression based on a random timer mechanism is given to avoid feedback implosion in the accurate measurement. The protocol is simple in its implementation. Simulations indicate that FLMCC shows good TCP-friendliness, responsiveness as well as intra-protocol fairness, and provides high link utilization.

  19. Decentralized Sensor Fusion for Ubiquitous Networking Robotics in Urban Areas

    PubMed Central

    Sanfeliu, Alberto; Andrade-Cetto, Juan; Barbosa, Marco; Bowden, Richard; Capitán, Jesús; Corominas, Andreu; Gilbert, Andrew; Illingworth, John; Merino, Luis; Mirats, Josep M.; Moreno, Plínio; Ollero, Aníbal; Sequeira, João; Spaan, Matthijs T.J.

    2010-01-01

    In this article we explain the architecture for the environment and sensors that has been built for the European project URUS (Ubiquitous Networking Robotics in Urban Sites), a project whose objective is to develop an adaptable network robot architecture for cooperation between network robots and human beings and/or the environment in urban areas. The project goal is to deploy a team of robots in an urban area to give a set of services to a user community. This paper addresses the sensor architecture devised for URUS and the type of robots and sensors used, including environment sensors and sensors onboard the robots. Furthermore, we also explain how sensor fusion takes place to achieve urban outdoor execution of robotic services. Finally some results of the project related to the sensor network are highlighted. PMID:22294927

  20. A Comprehensive Ubiquitous Healthcare Solution on an Android™ Mobile Device

    PubMed Central

    Hii, Pei-Cheng; Chung, Wan-Young

    2011-01-01

    Provision of ubiquitous healthcare solutions which provide healthcare services at anytime anywhere has become more favorable nowadays due to the emphasis on healthcare awareness and also the growth of mobile wireless technologies. Following this approach, an Android™ smart phone device is proposed as a mobile monitoring terminal to observe and analyze ECG (electrocardiography) waveforms from wearable ECG devices in real time under the coverage of a wireless sensor network (WSN). The exploitation of WSN in healthcare is able to substitute the complicated wired technology, moving healthcare away from a fixed location setting. As an extension to the monitoring scheme, medicine care is taken into consideration by utilizing the mobile phone as a barcode decoder, to verify and assist out-patients in the medication administration process, providing a better and more comprehensive healthcare service. PMID:22163986

  1. Decentralized sensor fusion for Ubiquitous Networking Robotics in Urban Areas.

    PubMed

    Sanfeliu, Alberto; Andrade-Cetto, Juan; Barbosa, Marco; Bowden, Richard; Capitán, Jesús; Corominas, Andreu; Gilbert, Andrew; Illingworth, John; Merino, Luis; Mirats, Josep M; Moreno, Plínio; Ollero, Aníbal; Sequeira, João; Spaan, Matthijs T J

    2010-01-01

    In this article we explain the architecture for the environment and sensors that has been built for the European project URUS (Ubiquitous Networking Robotics in Urban Sites), a project whose objective is to develop an adaptable network robot architecture for cooperation between network robots and human beings and/or the environment in urban areas. The project goal is to deploy a team of robots in an urban area to give a set of services to a user community. This paper addresses the sensor architecture devised for URUS and the type of robots and sensors used, including environment sensors and sensors onboard the robots. Furthermore, we also explain how sensor fusion takes place to achieve urban outdoor execution of robotic services. Finally some results of the project related to the sensor network are highlighted.

  2. Double-Layer Structured CO2 Adsorbent Functionalized with Modified Polyethyleneimine for High Physical and Chemical Stability.

    PubMed

    Jeon, Sunbin; Jung, Hyunchul; Kim, Sung Hyun; Lee, Ki Bong

    2018-06-18

    CO 2 capture using polyethyleneimine (PEI)-impregnated silica adsorbents has been receiving a lot of attention. However, the absence of physical stability (evaporation and leaching of amine) and chemical stability (urea formation) of the PEI-impregnated silica adsorbent has been generally established. Therefore, in this study, a double-layer impregnated structure, developed using modified PEI, is newly proposed to enhance the physical and chemical stabilities of the adsorbent. Epoxy-modified PEI and diepoxide-cross-linked PEI were impregnated via a dry impregnation method in the first and second layers, respectively. The physical stability of the double-layer structured adsorbent was noticeably enhanced when compared to the conventional adsorbents with a single layer. In addition to the enhanced physical stability, the result of simulated temperature swing adsorption cycles revealed that the double-layer structured adsorbent presented a high potential working capacity (3.5 mmol/g) and less urea formation under CO 2 -rich regeneration conditions. The enhanced physical and chemical stabilities as well as the high CO 2 working capacity of the double-layer structured adsorbent were mainly attributed to the second layer consisting of diepoxide-cross-linked PEI.

  3. Ubiquitous computing technology for just-in-time motivation of behavior change.

    PubMed

    Intille, Stephen S

    2004-01-01

    This paper describes a vision of health care where "just-in-time" user interfaces are used to transform people from passive to active consumers of health care. Systems that use computational pattern recognition to detect points of decision, behavior, or consequences automatically can present motivational messages to encourage healthy behavior at just the right time. Further, new ubiquitous computing and mobile computing devices permit information to be conveyed to users at just the right place. In combination, computer systems that present messages at the right time and place can be developed to motivate physical activity and healthy eating. Computational sensing technologies can also be used to measure the impact of the motivational technology on behavior.

  4. A New Remote Communications Link to Reduce Residential PV Solar Costs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    King, Randy; Sugiyama, Rod

    Monitoring of PV/DER site production is expensive to install and unreliable. Among third party systems providers, lost communications links are a growing concern. Nearly 20% of links are failing, provisioning is complex, recovery is expensive, production data is lost, and access is fragmented. FleetLink is a new concept in DER system communications, purpose built for lowering the cost of maintaining active contact with residential end user sites and ensuring that production data is reliably available to third party systems providers. Systems providers require accurate, secure system monitoring and reporting of production data and system faults while driving down overall costsmore » to compete effectively. This plug and play, independently operating communications solution lowers the cost of fleet contact from typically .08 dollars-$.12/W down to .02 dollars -.03/W including installation and maintenance expenses. FleetLink establishes a breakthrough in simplicity that facilitates rapid expansion of residential solar by reducing initial capital outlay and lowering installation labor time and skill levels. The solution also facilitates higher DER installation growth rates by driving down maintenance costs and eliminating communications trouble calls. This is accomplished by the FleetLink’s unique network technology that enables dynamic network configuration for fast changes, and active, self-healing DER site contact for uptime assurance. Using an open source network framework with proprietary, application specific enhancements, FleetLink independently manages connectivity, security, recovery, grid control communications, and fleet expansion while presenting a compliant SunSpec interface to the third party operations centers. The net system cost savings of at least .05 dollars/W supports the SunShot cost goals and the flexibility and scalability of the solution accelerates the velocity and ubiquitous adoption of solar.« less

  5. Agent-based user-adaptive service provision in ubiquitous systems

    NASA Astrophysics Data System (ADS)

    Saddiki, H.; Harroud, H.; Karmouch, A.

    2012-11-01

    With the increasing availability of smartphones, tablets and other computing devices, technology consumers have grown accustomed to performing all of their computing tasks anytime, anywhere and on any device. There is a greater need to support ubiquitous connectivity and accommodate users by providing software as network-accessible services. In this paper, we propose a MAS-based approach to adaptive service composition and provision that automates the selection and execution of a suitable composition plan for a given service. With agents capable of autonomous and intelligent behavior, the composition plan is selected in a dynamic negotiation driven by a utility-based decision-making mechanism; and the composite service is built by a coalition of agents each providing a component necessary to the target service. The same service can be built in variations for catering to dynamic user contexts and further personalizing the user experience. Also multiple services can be grouped to satisfy new user needs.

  6. Introducing Laptops to Children: An Examination of Ubiquitous Computing in Grade 3 Reading, Language, and Mathematics

    ERIC Educational Resources Information Center

    Bernard, Robert M.; Bethel, Edward Clement; Abrami, Philip C.; Wade, C. Anne

    2007-01-01

    This study examines the achievement outcomes accompanying the implementation of a Grade 3 laptop or so-­called "ubiquitous computing" program in a Quebec school district. CAT­3 reading, language, and mathematics batteries were administered at the end of Grade 2 and again at the end of Grade 3, after the first year of computer…

  7. Implementation of a real-time multi-channel gateway server in ubiquitous integrated biotelemetry system for emergency care (UIBSEC).

    PubMed

    Cheon, Gyeongwoo; Shin, Il Hyung; Jung, Min Yang; Kim, Hee Chan

    2009-01-01

    We developed a gateway server to support various types of bio-signal monitoring devices for ubiquitous emergency healthcare in a reliable, effective, and scalable way. The server provides multiple channels supporting real-time N-to-N client connections. We applied our system to four types of health monitoring devices including a 12-channel electrocardiograph (ECG), oxygen saturation (SpO(2)), and medical imaging devices (a ultrasonograph and a digital skin microscope). Different types of telecommunication networks were tested: WIBRO, CDMA, wireless LAN, and wired internet. We measured the performance of our system in terms of the transmission rate and the number of simultaneous connections. The results show that the proposed network communication strategy can be successfully applied to the ubiquitous emergency healthcare service by providing a fast rate enough for real-time video transmission and multiple connections among patients and medical personnel.

  8. Evidence for tyrosine-linked glycosaminoglycan in a bacterial surface protein.

    PubMed

    Peters, J; Rudolf, S; Oschkinat, H; Mengele, R; Sumper, M; Kellermann, J; Lottspeich, F; Baumeister, W

    1992-04-01

    The S-layer protein of Acetogenium kivui was subjected to proteolysis with different proteases and several high molecular mass glycosaminoglycan peptides containing glucose, galactosamine and an unidentified sugar-related component were separated by molecular sieve chromatography and reversed-phase HPLC and subjected to N-terminal sequence analysis. By methylation analysis glucose was found to be uniformly 1,6-linked, whereas galactosamine was exclusively 1,4-linked. Hydrazinolysis and subsequent amino-acid analysis as well as two-dimensional NMR spectroscopy were used to demonstrate that in these peptides carbohydrate was covalently linked to tyrosine. As all of the four Tyr-glycosylation sites were found to be preceded by valine, a new recognition sequence for glycosylation is suggested.

  9. Stratigraphy of the north polar layered deposits of Mars from high-resolution topography

    USGS Publications Warehouse

    Becerra, Patricio; Byrne, Shane; Sori, Michael M.; Sutton, Sarah; Herkenhoff, Kenneth E.

    2016-01-01

    The stratigraphy of the layered deposits of the polar regions of Mars is theorized to contain a record of recent climate change linked to insolation changes driven by variations in the planet's orbital and rotational parameters. In order to confidently link stratigraphic signals to insolation periodicities, a description of the stratigraphy is required based on quantities that directly relate to intrinsic properties of the layers. We use stereo Digital Terrain Models (DTMs) from the High Resolution Imaging Science Experiment (HiRISE) to derive a characteristic of North Polar Layered Deposits (NPLD) strata that can be correlated over large distances: the topographic protrusion of layers exposed in troughs, which is a proxy for the layers’ resistance to erosion. Using a combination of image analysis and a signal-matching algorithm to correlate continuous depth-protrusion signals taken from DTMs at different locations, we construct a stratigraphic column that describes the upper ~500 m of at least 7% of the area of the NPLD, and find accumulation rates that vary by factors of up to two. We find that, when coupled with observations of exposed layers in orbital images, the topographic expression of the strata is consistently continuous through large distances in the top 300 – 500 m of the NPLD, suggesting it is better related to intrinsic layer properties than brightness alone.

  10. Macular hole in juvenile X-linked retinoschisis.

    PubMed

    Al-Swaina, Nayef; Nowilaty, Sawsan R

    2013-10-01

    An 18 year-old male with no antecedent of trauma, systemic syndrome or myopia was referred for surgical treatment of a full thickness macular hole in the left eye. A more careful inspection revealed discrete foveal cystic changes in the fellow eye and subtle peripheral depigmented retinal pigment epithelial changes in both eyes. A spectral-domain optical coherence tomography (SD-OCT) scan confirmed, in addition to the full thickness macular hole in the left eye, microcystic spaces in the nuclear layers of both retinae. The diagnosis of X-linked retinoschisis was confirmed with a full field electroretinogram displaying the typical negative ERG. Macular holes are uncommon in the young and those complicating X-linked retinoschisis are rare. This report highlights the importance of investigating the presence of a macular hole in a young patient and illustrates the clinical and SD-OCT clues beyond the foveal center which led to the correct diagnosis of X-linked juvenile retinoschisis.

  11. Influence of cross-link structure, density and mechanical properties in the mesoscale deformation mechanisms of collagen fibrils.

    PubMed

    Depalle, Baptiste; Qin, Zhao; Shefelbine, Sandra J; Buehler, Markus J

    2015-12-01

    Collagen is a ubiquitous protein with remarkable mechanical properties. It is highly elastic, shows large fracture strength and enables substantial energy dissipation during deformation. Most of the connective tissue in humans consists of collagen fibrils composed of a staggered array of tropocollagen molecules, which are connected by intermolecular cross-links. In this study, we report a three-dimensional coarse-grained model of collagen and analyze the influence of enzymatic cross-links on the mechanics of collagen fibrils. Two representatives immature and mature cross-links are implemented in the mesoscale model using a bottom-up approach. By varying the number, type and mechanical properties of cross-links in the fibrils and performing tensile test on the models, we systematically investigate the deformation mechanisms of cross-linked collagen fibrils. We find that cross-linked fibrils exhibit a three phase behavior, which agrees closer with experimental results than what was obtained using previous models. The fibril mechanical response is characterized by: (i) an initial elastic deformation corresponding to the collagen molecule uncoiling, (ii) a linear regime dominated by molecule sliding and (iii) the second stiffer elastic regime related to the stretching of the backbone of the tropocollagen molecules until the fibril ruptures. Our results suggest that both cross-link density and type dictate the stiffness of large deformation regime by increasing the number of interconnected molecules while cross-links mechanical properties determine the failure strain and strength of the fibril. These findings reveal that cross-links play an essential role in creating an interconnected fibrillar material of tunable toughness and strength. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. OSI Network-layer Abstraction: Analysis of Simulation Dynamics and Performance Indicators

    NASA Astrophysics Data System (ADS)

    Lawniczak, Anna T.; Gerisch, Alf; Di Stefano, Bruno

    2005-06-01

    The Open Systems Interconnection (OSI) reference model provides a conceptual framework for communication among computers in a data communication network. The Network Layer of this model is responsible for the routing and forwarding of packets of data. We investigate the OSI Network Layer and develop an abstraction suitable for the study of various network performance indicators, e.g. throughput, average packet delay, average packet speed, average packet path-length, etc. We investigate how the network dynamics and the network performance indicators are affected by various routing algorithms and by the addition of randomly generated links into a regular network connection topology of fixed size. We observe that the network dynamics is not simply the sum of effects resulting from adding individual links to the connection topology but rather is governed nonlinearly by the complex interactions caused by the existence of all randomly added and already existing links in the network. Data for our study was gathered using Netzwerk-1, a C++ simulation tool that we developed for our abstraction.

  13. Evidence of linked biogeochemical and hydrological processes in homogeneous and layered vadose zone systems

    NASA Astrophysics Data System (ADS)

    McGuire, J. T.; Hansen, D. J.; Mohanty, B. P.

    2010-12-01

    Understanding chemical fate and transport in the vadose zone is critical to protect groundwater resources and preserve ecosystem health. However, prediction can be challenging due to the dynamic hydrologic and biogeochemical nature of the vadose zone. Additional controls on hydrobiogeochemical processes are added by subsurface structural heterogeneity. This study uses repacked soil column experiments to quantify linkages between microbial activity, geochemical cycling and hydrologic flow. Three “short” laboratory soil columns were constructed to evaluate the effects of soil layering: a homogenized medium-grained sand, homogenized organic-rich loam, and a sand-over-loam layered column. In addition, two “long” columns were constructed using either gamma-irradiated (sterilized) or untreated sediments to evaluate the effects of both soil layers and the presence of microorganisms. The long columns were packed identically; a medium-grained sand matrix with two vertically separated and horizontally offset lenses of organic-rich loam. In all 5 columns, downward and upward infiltration of water was evaluated to simulate rainfall and rising water table events respectively. In-situ colocated probes were used to measure soil water content, matric potential, Eh, major anions, ammonium, Fe2+, and total sulfide. Enhanced biogeochemical cycling was observed in the short layered column versus the short, homogeneous columns, and enumerations of iron and sulfate reducing bacteria were 1-2 orders of magnitude greater. In the long columns, microbial activity caused mineral bands and produced insoluble gases that impeded water flow through the pores of the sediment. Capillary barriers, formed around the lenses due to soil textural differences, retarded water flow rates through the lenses. This allowed reducing conditions to develop, evidenced by the production of Fe2+ and S2-. At the fringes of the lenses, Fe2+ oxidized to form Fe(III)-oxide bands that further retarded water

  14. Structure of the vault, a ubiquitous celular component.

    PubMed

    Kong, L B; Siva, A C; Rome, L H; Stewart, P L

    1999-04-15

    The vault is a ubiquitous and highly conserved ribonucleoprotein particle of approximately 13 MDa. This particle has been shown to be upregulated in certain multidrug-resistant cancer cell lines and to share a protein component with the telomerase complex. Determination of the structure of the vault was undertaken to provide a first step towards understanding the role of this cellular component in normal metabolism and perhaps to shed some light on its role in mediating drug resistance. Over 1300 particle images were combined to calculate an approximately 31 A resolution structure of the vault. Rotational power spectra did not yield a clear symmetry peak, either because of the thin, smooth walls or inherent flexibility of the vault. Although cyclic eightfold (C8) symmetry was imposed, the resulting reconstruction may be partially cylindrically averaged about the eightfold axis. Our results reveal the vault to be a hollow, barrel-like structure with two protruding caps and an invaginated waist. Although the normal cellular function of the vault is as yet undetermined, the structure of the vault is consistent with either a role in subcellular transport, as previously suggested, or in sequestering macromolecular assemblies.

  15. A concept for ubiquitous robotics in industrial environment

    NASA Astrophysics Data System (ADS)

    Sallinen, Mikko; Heilala, Juhani; Kivikunnas, Sauli

    2007-09-01

    In this paper a concept for industrial ubiquitous robotics is presented. The concept combines two different approaches to manage agile, adaptable production: firstly the human operator is strongly in the production loop and secondly, the robot workcell will be more autonomous and smarter to manage production. This kind of autonomous robot cell can be called production island. Communication to the human operator working in this kind of smart industrial environment can be divided into two levels: body area communication and operator-infrastructure communication including devices, machines and infra. Body area communication can be supportive in two directions: data is recorded by means of measuring physical actions, such as hand movements, body gestures or supportive when it will provide information to user such as guides or manuals for operation. Body area communication can be carried out using short range communication technologies such as NFC (Near Field communication) which is RFID type of communication. In the operator-infrastructure communication, WLAN or Bluetooth -communication can be used. Beyond the current Human Machine interaction HMI systems, the presented system concept is designed to fulfill the requirements for hybrid, knowledge intensive manufacturing in the future, where humans and robots operate in close co-operation.

  16. The CCSDS return all frames Space Link Extension service

    NASA Technical Reports Server (NTRS)

    Uhrig, Hans; Pietras, John; Stoloff, Michael

    1994-01-01

    Existing Consultative Committee for Space Data Systems (CCSDS) Recommendations for Telemetry Channel Coding, Packet Telemetry, Advanced Orbiting Systems, and Telecommand have facilitated cross-support between Agencies by standardizing the link between spacecraft and ground terminal. CCSDS is currently defining a set of Space Link Extension (SLE) services that will enable remote science and mission operations facilities to access the ground termination of the Space Link services in a standard manner. The first SLE service to be defined is the Return All Frames (RAF) service. The RAF service delivers all CCSDS link-layer frames received on a single space link physical channel. The service provides both on-line and off-line data transfer modes to accommodate the variety of access methods typical of space mission operations. This paper describes the RAF service as of the Summer of 1994. It characterizes the behavior of the service as seen across the interface between the user and the service and gives an overview of the interactions involved in setting up and operating the service in a cross-support environment.

  17. MULTIMODAL IMAGING OF MOSAIC RETINOPATHY IN CARRIERS OF HEREDITARY X-LINKED RECESSIVE DISEASES.

    PubMed

    Wu, An-Lun; Wang, Jung-Pan; Tseng, Yun-Ju; Liu, Laura; Kang, Yu-Chuan; Chen, Kuan-Jen; Chao, An-Ning; Yeh, Lung-Kun; Chen, Tun-Lu; Hwang, Yih-Shiou; Wu, Wei-Chi; Lai, Chi-Chun; Wang, Nan-Kai

    2018-05-01

    To investigate the clinical features in carriers of X-linked retinitis pigmentosa, X-linked ocular albinism, and choroideremia (CHM) using multimodal imaging and to assess their diagnostic value in these three mosaic retinopathies. We prospectively examined 14 carriers of 3 X-linked recessive disorders (X-linked retinitis pigmentosa, X-linked ocular albinism, and CHM). Details of abnormalities of retinal morphology were evaluated using fundus photography, fundus autofluorescence (FAF) imaging, and spectral domain optical coherence tomography. In six X-linked retinitis pigmentosa carriers, fundus appearance varied from unremarkable to the presence of tapetal-like reflex and pigmentary changes. On FAF imaging, all carriers exhibited a bright radial reflex against a dark background. By spectral domain optical coherence tomography, loss of the ellipsoid zone in the macula was observed in 3 carriers (50%). Regarding the retinal laminar architecture, 4 carriers (66.7%) showed thinning of the outer nuclear layer and a dentate appearance of the outer plexiform layer. All five X-linked ocular albinism carriers showed a characteristic mud-splatter patterned fundus, dark radial streaks against a bright background on FAF imaging, and a normal-appearing retinal structure by spectral domain optical coherence tomography imaging. Two of the 3 CHM carriers (66.7%) showed a diffuse moth-eaten appearance of the fundus, and all 3 showed irregular hyper-FAF and hypo-FAF spots throughout the affected area. In the CHM carriers, the structural changes observed by spectral domain optical coherence tomography imaging were variable. Our findings in an Asian cohort suggest that FAF imaging is a practical diagnostic test for differentiating X-linked retinitis pigmentosa, X-linked ocular albinism, and CHM carriers. Wide-field FAF is an easy and helpful adjunct to testing for the correct diagnosis and identification of lyonization in carriers of these three mosaic retinopathies.

  18. Inferring topologies via driving-based generalized synchronization of two-layer networks

    NASA Astrophysics Data System (ADS)

    Wang, Yingfei; Wu, Xiaoqun; Feng, Hui; Lu, Jun-an; Xu, Yuhua

    2016-05-01

    The interaction topology among the constituents of a complex network plays a crucial role in the network’s evolutionary mechanisms and functional behaviors. However, some network topologies are usually unknown or uncertain. Meanwhile, coupling delays are ubiquitous in various man-made and natural networks. Hence, it is necessary to gain knowledge of the whole or partial topology of a complex dynamical network by taking into consideration communication delay. In this paper, topology identification of complex dynamical networks is investigated via generalized synchronization of a two-layer network. Particularly, based on the LaSalle-type invariance principle of stochastic differential delay equations, an adaptive control technique is proposed by constructing an auxiliary layer and designing proper control input and updating laws so that the unknown topology can be recovered upon successful generalized synchronization. Numerical simulations are provided to illustrate the effectiveness of the proposed method. The technique provides a certain theoretical basis for topology inference of complex networks. In particular, when the considered network is composed of systems with high-dimension or complicated dynamics, a simpler response layer can be constructed, which is conducive to circuit design. Moreover, it is practical to take into consideration perturbations caused by control input. Finally, the method is applicable to infer topology of a subnetwork embedded within a complex system and locate hidden sources. We hope the results can provide basic insight into further research endeavors on understanding practical and economical topology inference of networks.

  19. Extracurricular involvement among affluent youth: a scapegoat for "ubiquitous achievement pressures"?

    PubMed

    Luthar, Suniya S; Shoum, Karen A; Brown, Pamela J

    2006-05-01

    It has been suggested that over-scheduling of upper-class youth might underlie the high distress and substance use documented among them. This assumption was tested by considering suburban 8th graders' involvement in different activities along with their perceptions of parental attitudes toward achievement. Results indicated negligible evidence for deleterious effects of high extracurricular involvement per se. Far more strongly implicated was perceived parent criticism for both girls and boys as well as the absence of after-school supervision. Low parent expectations connoted significant vulnerability especially for boys. The findings indicate that at least among early adolescents, converging scientific and media reports may have scapegoated extracurricular involvements, to some degree, as an index of ubiquitous achievement pressures in affluent communities. ((c) 2006 APA, all rights reserved).

  20. A ubiquitous ice size bias in simulations of tropical deep convection

    NASA Astrophysics Data System (ADS)

    Stanford, McKenna W.; Varble, Adam; Zipser, Ed; Strapp, J. Walter; Leroy, Delphine; Schwarzenboeck, Alfons; Potts, Rodney; Protat, Alain

    2017-08-01

    The High Altitude Ice Crystals - High Ice Water Content (HAIC-HIWC) joint field campaign produced aircraft retrievals of total condensed water content (TWC), hydrometeor particle size distributions (PSDs), and vertical velocity (w) in high ice water content regions of mature and decaying tropical mesoscale convective systems (MCSs). The resulting dataset is used here to explore causes of the commonly documented high bias in radar reflectivity within cloud-resolving simulations of deep convection. This bias has been linked to overly strong simulated convective updrafts lofting excessive condensate mass but is also modulated by parameterizations of hydrometeor size distributions, single particle properties, species separation, and microphysical processes. Observations are compared with three Weather Research and Forecasting model simulations of an observed MCS using different microphysics parameterizations while controlling for w, TWC, and temperature. Two popular bulk microphysics schemes (Thompson and Morrison) and one bin microphysics scheme (fast spectral bin microphysics) are compared. For temperatures between -10 and -40 °C and TWC > 1 g m-3, all microphysics schemes produce median mass diameters (MMDs) that are generally larger than observed, and the precipitating ice species that controls this size bias varies by scheme, temperature, and w. Despite a much greater number of samples, all simulations fail to reproduce observed high-TWC conditions ( > 2 g m-3) between -20 and -40 °C in which only a small fraction of condensate mass is found in relatively large particle sizes greater than 1 mm in diameter. Although more mass is distributed to large particle sizes relative to those observed across all schemes when controlling for temperature, w, and TWC, differences with observations are significantly variable between the schemes tested. As a result, this bias is hypothesized to partly result from errors in parameterized hydrometeor PSD and single particle

  1. A cloud-based X73 ubiquitous mobile healthcare system: design and implementation.

    PubMed

    Ji, Zhanlin; Ganchev, Ivan; O'Droma, Máirtín; Zhang, Xin; Zhang, Xueji

    2014-01-01

    Based on the user-centric paradigm for next generation networks, this paper describes a ubiquitous mobile healthcare (uHealth) system based on the ISO/IEEE 11073 personal health data (PHD) standards (X73) and cloud computing techniques. A number of design issues associated with the system implementation are outlined. The system includes a middleware on the user side, providing a plug-and-play environment for heterogeneous wireless sensors and mobile terminals utilizing different communication protocols and a distributed "big data" processing subsystem in the cloud. The design and implementation of this system are envisaged as an efficient solution for the next generation of uHealth systems.

  2. A Cloud-Based X73 Ubiquitous Mobile Healthcare System: Design and Implementation

    PubMed Central

    Ji, Zhanlin; O'Droma, Máirtín; Zhang, Xin; Zhang, Xueji

    2014-01-01

    Based on the user-centric paradigm for next generation networks, this paper describes a ubiquitous mobile healthcare (uHealth) system based on the ISO/IEEE 11073 personal health data (PHD) standards (X73) and cloud computing techniques. A number of design issues associated with the system implementation are outlined. The system includes a middleware on the user side, providing a plug-and-play environment for heterogeneous wireless sensors and mobile terminals utilizing different communication protocols and a distributed “big data” processing subsystem in the cloud. The design and implementation of this system are envisaged as an efficient solution for the next generation of uHealth systems. PMID:24737958

  3. Wrinkled Few-Layer Graphene as Highly Efficient Load Bearer.

    PubMed

    Androulidakis, Charalampos; Koukaras, Emmanuel N; Rahova, Jaroslava; Sampathkumar, Krishna; Parthenios, John; Papagelis, Konstantinos; Frank, Otakar; Galiotis, Costas

    2017-08-09

    Multilayered graphitic materials are not suitable as load-bearers due to their inherent weak interlayer bonding (for example, graphite is a solid lubricant in certain applications). This situation is largely improved when two-dimensional (2D) materials such as a monolayer (SLG) graphene are employed. The downside in these cases is the presence of thermally or mechanically induced wrinkles which are ubiquitous in 2D materials. Here we set out to examine the effect of extensive large wavelength/amplitude wrinkling on the stress transfer capabilities of exfoliated simply supported graphene flakes. Contrary to common belief we present clear evidence that this type of "corrugation" enhances the load-bearing capacity of few-layer graphene as compared to "flat" specimens. This effect is the result of the significant increase of the graphene/polymer interfacial shear stress per increment of applied strain due to wrinkling and paves the way for designing affordable graphene composites with highly improved stress-transfer efficiency.

  4. Loss of the Endothelial Glycocalyx Links Albuminuria and Vascular Dysfunction

    PubMed Central

    Ferguson, Joanne K.; Burford, James L.; Gevorgyan, Haykanush; Nakano, Daisuke; Harper, Steven J.; Bates, David O.; Peti-Peterdi, Janos

    2012-01-01

    Patients with albuminuria and CKD frequently have vascular dysfunction but the underlying mechanisms remain unclear. Because the endothelial surface layer, a meshwork of surface-bound and loosely adherent glycosaminoglycans and proteoglycans, modulates vascular function, its loss could contribute to both renal and systemic vascular dysfunction in proteinuric CKD. Using Munich-Wistar-Fromter (MWF) rats as a model of spontaneous albuminuric CKD, multiphoton fluorescence imaging and single-vessel physiology measurements revealed that old MWF rats exhibited widespread loss of the endothelial surface layer in parallel with defects in microvascular permeability to both water and albumin, in both continuous mesenteric microvessels and fenestrated glomerular microvessels. In contrast to young MWF rats, enzymatic disruption of the endothelial surface layer in old MWF rats resulted in neither additional loss of the layer nor additional changes in permeability. Intravenous injection of wheat germ agglutinin lectin and its adsorption onto the endothelial surface layer significantly improved glomerular albumin permeability. Taken together, these results suggest that widespread loss of the endothelial surface layer links albuminuric kidney disease with systemic vascular dysfunction, providing a potential therapeutic target for proteinuric kidney disease. PMID:22797190

  5. The near‐global mesospheric potassium layer: Observations and modeling

    PubMed Central

    Dawkins, E. C. M.; Chipperfield, M. P.; Feng, W.

    2015-01-01

    Abstract The meteoric metal layers act as unique tracers of chemistry and dynamics in the upper atmosphere. Existing lidar studies from a few locations show that K exhibits a semiannual seasonality (winter and summer maxima), quite unlike the annual seasonality (winter maximum and summer minimum) seen with Na and Fe. This work uses spaceborne observations made with the Optical Spectrograph and InfraRed Imager System instrument on the Odin satellite to retrieve the near‐global K layer for the first time. The satellite data (2004 to mid‐2013) are used to validate the implementation of a recently proposed potassium chemistry scheme in a whole atmosphere chemistry climate model, which provides a chemical basis for this semiannual seasonal behavior. The satellite and model data show that this semiannual seasonality is near global in extent, with the strongest variation at middle and high latitudes. The column abundance, centroid layer height, and root‐mean‐square width of the K layer are consistent with the limited available lidar record. The K data set is then used to investigate the impact of polar mesospheric clouds on the metal layers at high latitudes during summer. Finally, the occurrence frequency of sporadic K layers and their possible link to sporadic E layers are examined. PMID:27478716

  6. Prevention of sexually transmitted infections using mobile devices and ubiquitous computing.

    PubMed

    Besoain, Felipe; Perez-Navarro, Antoni; Caylà, Joan A; Aviñó, Constanza Jacques; de Olalla, Patricia García

    2015-05-03

    Advances in the development of information and communication technologies have facilitated social interrelationships, but also sexual contacts without appropriate preventive measures. In this paper, we will focus on situations in which people use applications to meet sexual partners nearby, which could increase their chance of exposure to sexually transmitted infections (STI). How can we encourage users to adopt preventive measures without violating their privacy or infringing on the character of the application? To achieve the goal of preventing STI, we have used the design and creation methodology and have developed a prototype software package. This prototype follows the RESTful services principles and has two parts: an Android OS application with emphasis on ubiquitous computing and designed according to General Responsibility Assignment Software Patterns (GRASP), and a server with a web page. To choose the preventive messages, we performed a test in 17 men who have sex with men (MSM). Our software sends preventive notifications to users when it detects situations such as the activation of particular applications on their smartphones, or their proximity to areas with a high probability of intercourse (hot zones). The underlying idea is the same as that for warning messages on cigarette packets, since users read the message just when they are going to smoke. The messages used have been selected from a list that has been rated by the users themselves. The most popular message is "Enjoy sex and enjoy life. Do not expose yourself to HIV". The user is unaware of the software, which runs in the background. Ubiquitous computing may be useful for alerting users with preventive and educational messages. The proposed application is non-intrusive because: 1) the users themselves decide to install it and, therefore, users' privacy rights are preserved; 2) it sends a message that helps users think about taking appropriate preventive measures; and 3) it works in the

  7. A Decision-Tree-Oriented Guidance Mechanism for Conducting Nature Science Observation Activities in a Context-Aware Ubiquitous Learning

    ERIC Educational Resources Information Center

    Hwang, Gwo-Jen; Chu, Hui-Chun; Shih, Ju-Ling; Huang, Shu-Hsien; Tsai, Chin-Chung

    2010-01-01

    A context-aware ubiquitous learning environment is an authentic learning environment with personalized digital supports. While showing the potential of applying such a learning environment, researchers have also indicated the challenges of providing adaptive and dynamic support to individual students. In this paper, a decision-tree-oriented…

  8. Ubiquitous time variability of integrated stellar populations.

    PubMed

    Conroy, Charlie; van Dokkum, Pieter G; Choi, Jieun

    2015-11-26

    Long-period variable stars arise in the final stages of the asymptotic giant branch phase of stellar evolution. They have periods of up to about 1,000 days and amplitudes that can exceed a factor of three in the I-band flux. These stars pulsate predominantly in their fundamental mode, which is a function of mass and radius, and so the pulsation periods are sensitive to the age of the underlying stellar population. The overall number of long-period variables in a population is directly related to their lifetimes, which is difficult to predict from first principles because of uncertainties associated with stellar mass-loss and convective mixing. The time variability of these stars has not previously been taken into account when modelling the spectral energy distributions of galaxies. Here we construct time-dependent stellar population models that include the effects of long-period variable stars, and report the ubiquitous detection of this expected 'pixel shimmer' in the massive metal-rich galaxy M87. The pixel light curves display a variety of behaviours. The observed variation of 0.1 to 1 per cent is very well matched to the predictions of our models. The data provide a strong constraint on the properties of variable stars in an old and metal-rich stellar population, and we infer that the lifetime of long-period variables in M87 is shorter by approximately 30 per cent compared to predictions from the latest stellar evolution models.

  9. Ubiquitous computing in sports: A review and analysis.

    PubMed

    Baca, Arnold; Dabnichki, Peter; Heller, Mario; Kornfeind, Philipp

    2009-10-01

    Ubiquitous (pervasive) computing is a term for a synergetic use of sensing, communication and computing. Pervasive use of computing has seen a rapid increase in the current decade. This development has propagated in applied sport science and everyday life. The work presents a survey of recent developments in sport and leisure with emphasis on technology and computational techniques. A detailed analysis on new technological developments is performed. Sensors for position and motion detection, and such for equipment and physiological monitoring are discussed. Aspects of novel trends in communication technologies and data processing are outlined. Computational advancements have started a new trend - development of smart and intelligent systems for a wide range of applications - from model-based posture recognition to context awareness algorithms for nutrition monitoring. Examples particular to coaching and training are discussed. Selected tools for monitoring rules' compliance and automatic decision-making are outlined. Finally, applications in leisure and entertainment are presented, from systems supporting physical activity to systems providing motivation. It is concluded that the emphasis in future will shift from technologies to intelligent systems that allow for enhanced social interaction as efforts need to be made to improve user-friendliness and standardisation of measurement and transmission protocols.

  10. Identification of O-linked β-d-N-acetylglucosamine-Modified Proteins from Arabidopsis

    PubMed Central

    Xu, Shou-Ling; Chalkley, Robert J.; Wang, Zhi-Yong; Burlingame, Alma L.

    2013-01-01

    The posttranslational modification of proteins with O-linked β-d-N-acetylglucosamine (O-GlcNAc) on serine and threonine residues occurs in all animals and plants. This modification is dynamic and ubiquitous, and regulates many cellular processes, including transcription, signaling and cytokinesis and is associated with several diseases. Cycling of O-GlcNAc is tightly regulated by O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA). Plants have two OGTs, SPINDLY (SPY) and SECRET AGENT (SEC); disruption of both causes embryo lethality. Despite O-GlcNAc modification of proteins being discovered more than 20-years ago, identification and mapping of protein GlcNAcylation is still a challenging task. Here we describe the use of lectin affinity chromatography combined with electron transfer dissociation mass spectrometry to enrich and to detect O-GlcNAc modified peptides from Arabidopsis. PMID:22576084

  11. Biomedical digital assistant for ubiquitous healthcare.

    PubMed

    Lee, Tae-Soo; Hong, Joo-Hyun; Cho, Myeong-Chan

    2007-01-01

    The concept of ubiquitous healthcare service, which emerged as one of measures to solve healthcare problems in aged society, means that patients can receive services such as prevention, diagnosis, therapy and prognosis management at any time and in any place with the help of advanced information and communication technology. This service requires not only biomedical digital assistant that can monitor continuously the patients' health condition regardless of time and place, but also wired and wireless communication devices and telemedicine servers that provide doctors with data on patients' present health condition. In order to implement a biomedical digital assistant that is portable and wearable to patients, the present study developed a device that minimizes size, weight and power consumption, measures ECG and PPG signals, and even monitors moving patients' state. The biomedical sensor with the function of wireless communication was designed to be highly portable and wearable, to be operable 24 hours with small-size batteries, and to monitor the subject's heart rate, step count and respiratory rate in his daily life. The biomedical signal receiving device was implemented in two forms, PDA and cellular phone. The movement monitoring device embedded in the battery pack of a cellular phone does not have any problem in operating 24 hours, but the real-time biomedical signal receiving device implemented with PDA operated up to 6 hours due to the limited battery capacity of PDA. This problem is expected to be solved by reducing wireless communication load through improving the processing and storage functions of the sensor. The developed device can transmit a message on the patient's emergency to the remote server through the cellular phone network, and is expected to play crucial roles in the health management of chronic-aged patients in their daily life.

  12. Optical wireless link between a nanoscale antenna and a transducing rectenna.

    PubMed

    Dasgupta, Arindam; Mennemanteuil, Marie-Maxime; Buret, Mickaël; Cazier, Nicolas; Colas-des-Francs, Gérard; Bouhelier, Alexandre

    2018-05-18

    Initiated as a cable-replacement solution, short-range wireless power transfer has rapidly become ubiquitous in the development of modern high-data throughput networking in centimeter to meter accessibility range. Wireless technology is now penetrating a higher level of system integration for chip-to-chip and on-chip radiofrequency interconnects. However, standard CMOS integrated millimeter-wave antennas have typical size commensurable with the operating wavelength, and are thus an unrealistic solution for downsizing transmitters and receivers to the micrometer and nanometer scale. Herein, we demonstrate a light-in and electrical signal-out, on-chip wireless near-infrared link between a 220 nm optical antenna and a sub-nanometer rectifying antenna converting the transmitted optical energy into direct electrical current. The co-integration of subwavelength optical functional devices with electronic transduction offers a disruptive solution to interface photons and electrons at the nanoscale for on-chip wireless optical interconnects.

  13. Ubiquitous Geometry: Some Examples Showing the Significance of Size and Shape in the Works of Man and Nature.

    ERIC Educational Resources Information Center

    Bachman, C. H.

    1988-01-01

    Presents examples to show the ubiquitous nature of geometry. Illustrates the relationship between the perimeter and area of two-dimensional objects and between the area and volume of three-dimensional objects. Provides examples of distribution systems, optimum shapes, structural strength, biological heat engines, man's size, and reflection and…

  14. Shifting Contexts: Investigating the Role of Context in the Use of Ubiquitous Computing for Design-Based Learning

    ERIC Educational Resources Information Center

    Willis, Katharine S.; Corino, Gianni

    2014-01-01

    In design teaching ubiquitous technologies can offer new ways of situating learning within real world experiences. Yet they require new types of knowledge; both an understanding of how to work with the technology and also an understanding of how to use the technologies to respond to changing contexts such as the place and the people. We sought to…

  15. Physical-layer network coding in coherent optical OFDM systems.

    PubMed

    Guan, Xun; Chan, Chun-Kit

    2015-04-20

    We present the first experimental demonstration and characterization of the application of optical physical-layer network coding in coherent optical OFDM systems. It combines two optical OFDM frames to share the same link so as to enhance system throughput, while individual OFDM frames can be recovered with digital signal processing at the destined node.

  16. Linking boundary-layer circulations and surface processes during FIFE89. Part 1: Observational analysis

    NASA Technical Reports Server (NTRS)

    Smith, Eric A.; Wai, Mickey M.-K.; Cooper, Harry J.; Rubes, Michael T.; Hsu, Ann

    1994-01-01

    Surface, aircraft, and satellite observations are analyzed for the 21-day 1989 intensive field campaign of the First ISLSCP Field Experiment (FIFE) to determine the effect of precipitation, vegetation, and soil moisture distributions on the thermal properties of the surface including the heat and moisture fluxes, and the corresponding response in the boundary-layer circulation. Mean and variance properties of the surface variables are first documented at various time and space scales. These calculations are designed to set the stage for Part 2, a modeling study that will focus on how time-space dependent rainfall distribution influences the intensity of the feedback between a vegetated surface and the atmospheric boundary layer. Further analysis shows strongly demarked vegetation and soil moisture gradients extending across the FIFE experimental site that were developed and maintained by the antecedent and ongoing spatial distribution of rainfall over the region. These gradients are shown to have a pronounced influence on the thermodynamic properties of the surface. Furthermore, perturbation surface wind analysis suggests for both short-term steady-state conditions and long-term averaged conditions that the gradient pattern maintained a diurnally oscillating local direct circulation with perturbation vertical velocities of the same order as developing cumulus clouds. Dynamical and scaling considerations suggest that the embedded perturbation circulation is driven by surface heating/cooling gradients and terrain ef fects rather than the manifestation of an inertial oscillation. The implication is that at even relatively small scales (less than 30 km), the differential evolution in vegetation density and soil moisture distribution over a relatively homogenous ecotone can give rise to preferential boundary-layer circulations capable of modifying local-scale horizontal and vertical motions.

  17. Children's Models of Understanding of Two Major Global Environmental Issues (Ozone Layer and Greenhouse Effect).

    ERIC Educational Resources Information Center

    Boyes, Edward; Stanisstreet, Martin

    1997-01-01

    Aims to quantify the models that 13- and 14 year-old students hold about the causes of the greenhouse effect and ozone layer depletion. Assesses the prevalence of those ideas that link the two phenomena. Twice as many students think that holes in the ozone layer cause the greenhouse effect than think the greenhouse effect causes ozone depletion.…

  18. Correlating High Resolution Radar Reflectors with Visible Layering of the Polar Layered Deposits, Mars

    NASA Astrophysics Data System (ADS)

    Christian, S.; Holt, J. W.; Choudhary, P.; Fishbaugh, K. E.; Plaut, J. J.

    2010-12-01

    between geometries and have now determined visible layers demonstrate similar subsurface topographic features as those revealed by SHARAD. Direct elevation comparisons between individual reflectors and discrete optical layers, while considered necessary for a correlation, are complicated by variations in subsurface structure that exist between the outcrop and the SHARAD tracks, as inferred from our mapping. While a direct correlation has not yet been accomplished, we have confirmed a genetic link between radar reflectors and visible layers; furthermore, we have generalized and improved the techniques for conducting such correlations so this can be undertaken at additional locations.

  19. Evidence of Ubiquitous Large-Amplitude Alfven waves in the Global Field-Aligned Current System

    NASA Astrophysics Data System (ADS)

    Pakhotin, I.; Mann, I.; Lysak, R. L.; Knudsen, D. J.; Burchill, J. K.; Gjerloev, J. W.; Rae, J.; Forsyth, C.; Murphy, K. R.; Miles, D.; Ozeke, L.; Balasis, G.

    2017-12-01

    Large-amplitude non-stationarities have been observed during an analysis of a quiescent field-aligned current system crossing using the multi-satellite Swarm constellation. Using simultaneous electric and magnetic field measurements it has been determined that these non-stationarities, reaching tens to hundreds of nanoteslas, are Alfvenic in nature. Evidence suggests that these large-amplitude Alfven waves are a ubiquitous, fundamentally inherent feature of and exist in a continuum with larger-scale field-aligned currents, and both can be explained using the same physical paradigm of reflected Alfven waves.

  20. Developing functional musculoskeletal tissues through hypoxia and lysyl oxidase-induced collagen cross-linking

    PubMed Central

    Makris, Eleftherios A.; Responte, Donald J.; Hu, Jerry C.; Athanasiou, Kyriacos A.

    2014-01-01

    The inability to recapitulate native tissue biomechanics, especially tensile properties, hinders progress in regenerative medicine. To address this problem, strategies have focused on enhancing collagen production. However, manipulating collagen cross-links, ubiquitous throughout all tissues and conferring mechanical integrity, has been underinvestigated. A series of studies examined the effects of lysyl oxidase (LOX), the enzyme responsible for the formation of collagen cross-links. Hypoxia-induced endogenous LOX was applied in multiple musculoskeletal tissues (i.e., cartilage, meniscus, tendons, ligaments). Results of these studies showed that both native and engineered tissues are enhanced by invoking a mechanism of hypoxia-induced pyridinoline (PYR) cross-links via intermediaries like LOX. Hypoxia was shown to enhance PYR cross-linking 1.4- to 6.4-fold and, concomitantly, to increase the tensile properties of collagen-rich tissues 1.3- to 2.2-fold. Direct administration of exogenous LOX was applied in native cartilage and neocartilage generated using a scaffold-free, self-assembling process of primary chondrocytes. Exogenous LOX was found to enhance native tissue tensile properties 1.9-fold. LOX concentration- and time-dependent increases in PYR content (∼16-fold compared with controls) and tensile properties (approximately fivefold compared with controls) of neocartilage were also detected, resulting in properties on par with native tissue. Finally, in vivo subcutaneous implantation of LOX-treated neocartilage in nude mice promoted further maturation of the neotissue, enhancing tensile and PYR content approximately threefold and 14-fold, respectively, compared with in vitro controls. Collectively, these results provide the first report, to our knowledge, of endogenous (hypoxia-induced) and exogenous LOX applications for promoting collagen cross-linking and improving the tensile properties of a spectrum of native and engineered tissues both in vitro and in

  1. Hyperactivity in Boys with Attention-Deficit/Hyperactivity Disorder (ADHD): A Ubiquitous Core Symptom or Manifestation of Working Memory Deficits?

    ERIC Educational Resources Information Center

    Rapport, Mark D.; Bolden, Jennifer; Kofler, Michael J.; Sarver, Dustin E.; Raiker, Joseph S.; Alderson, R. Matt

    2009-01-01

    Hyperactivity is currently considered a core and ubiquitous feature of attention-deficit/hyperactivity disorder (ADHD); however, an alternative model challenges this premise and hypothesizes a functional relationship between working memory (WM) and activity level. The current study investigated whether children's activity level is functionally…

  2. Wireless Technologies, Ubiquitous Computing and Mobile Health: Application to Drug Abuse Treatment and Compliance with HIV Therapies.

    PubMed

    Boyer, Edward W; Smelson, David; Fletcher, Richard; Ziedonis, Douglas; Picard, Rosalind W

    2010-06-01

    Beneficial advances in the treatment of substance abuse and compliance with medical therapies, including HAART, are possible with new mobile technologies related to personal physiological sensing and computational methods. When incorporated into mobile platforms that allow for ubiquitous computing, these technologies have great potential for extending the reach of behavioral interventions from clinical settings where they are learned into natural environments.

  3. Exploring the Effects of Web-Mediated Computational Thinking on Developing Students' Computing Skills in a Ubiquitous Learning Environment

    ERIC Educational Resources Information Center

    Tsai, Chia-Wen; Shen, Pei-Di; Tsai, Meng-Chuan; Chen, Wen-Yu

    2017-01-01

    Much application software education in Taiwan can hardly be regarded as practical. The researchers in this study provided a flexible means of ubiquitous learning (u-learning) with a mobile app for students to access the learning material. In addition, the authors also adopted computational thinking (CT) to help students develop practical computing…

  4. Extracurricular Involvement Among Affluent Youth: A Scapegoat for “Ubiquitous Achievement Pressures”?

    PubMed Central

    Luthar, Suniya S.; Shoum, Karen A.; Brown, Pamela J.

    2007-01-01

    It has been suggested that overscheduling of upper-class youth might underlie the high distress and substance use documented among them. This assumption was tested by considering suburban 8th graders’ involvement in different activities along with their perceptions of parental attitudes toward achievement. Results indicated negligible evidence for deleterious effects of high extracurricular involvement per se. Far more strongly implicated was perceived parent criticism for both girls and boys as well as the absence of after-school supervision. Low parent expectations connoted significant vulnerability especially for boys. The findings indicate that at least among early adolescents, converging scientific and media reports may have scapegoated extracurricular involvements, to some degree, as an index of ubiquitous achievement pressures in affluent communities. PMID:16756447

  5. PhysioDroid: Combining Wearable Health Sensors and Mobile Devices for a Ubiquitous, Continuous, and Personal Monitoring

    PubMed Central

    Villalonga, Claudia; Damas, Miguel

    2014-01-01

    Technological advances on the development of mobile devices, medical sensors, and wireless communication systems support a new generation of unobtrusive, portable, and ubiquitous health monitoring systems for continuous patient assessment and more personalized health care. There exist a growing number of mobile apps in the health domain; however, little contribution has been specifically provided, so far, to operate this kind of apps with wearable physiological sensors. The PhysioDroid, presented in this paper, provides a personalized means to remotely monitor and evaluate users' conditions. The PhysioDroid system provides ubiquitous and continuous vital signs analysis, such as electrocardiogram, heart rate, respiration rate, skin temperature, and body motion, intended to help empower patients and improve clinical understanding. The PhysioDroid is composed of a wearable monitoring device and an Android app providing gathering, storage, and processing features for the physiological sensor data. The versatility of the developed app allows its use for both average users and specialists, and the reduced cost of the PhysioDroid puts it at the reach of most people. Two exemplary use cases for health assessment and sports training are presented to illustrate the capabilities of the PhysioDroid. Next technical steps include generalization to other mobile platforms and health monitoring devices. PMID:25295301

  6. The Characteristics of Ubiquitous and Unique Leptospira Strains from the Collection of Russian Centre for Leptospirosis

    PubMed Central

    Voronina, Olga L.; Kunda, Marina S.; Aksenova, Ekaterina I.; Ryzhova, Natalia N.; Semenov, Andrey N.; Petrov, Evgeny M.; Didenko, Lubov V.; Lunin, Vladimir G.; Ananyina, Yuliya V.; Gintsburg, Alexandr L.

    2014-01-01

    Background and Aim. Leptospira, the causal agent of leptospirosis, has been isolated from the environment, patients, and wide spectrum of animals in Russia. However, the genetic diversity of Leptospira in natural and anthropurgic foci was not clearly defined. Methods. The recent MLST scheme was used for the analysis of seven pathogenic species. 454 pyrosequencing technology was the base of the whole genome sequencing (WGS). Results. The most wide spread and prevalent Leptospira species in Russia were L. interrogans, L. kirschneri, and L. borgpetersenii. Five STs, common for Russian strains: 37, 17, 199, 110, and 146, were identified as having a longtime and ubiquitous distribution in various geographic areas. Unexpected properties were revealed for the environmental Leptospira strain Bairam-Ali. WGS of this strain genome suggested that it combined the features of the pathogenic and nonpathogenic strains and may be a reservoir of the natural resistance genes. Results of the comparative analysis of rrs and rpoB genes and MLST loci for different Leptospira species strains and phenotypic and serological properties of the strain Bairam-Ali suggested that it represented separate Leptospira species. Conclusions. Thus, the natural and anthropurgic foci supported ubiquitous Leptospira species and the pool of genes important for bacterial adaptivity to various conditions. PMID:25276806

  7. PhysioDroid: combining wearable health sensors and mobile devices for a ubiquitous, continuous, and personal monitoring.

    PubMed

    Banos, Oresti; Villalonga, Claudia; Damas, Miguel; Gloesekoetter, Peter; Pomares, Hector; Rojas, Ignacio

    2014-01-01

    Technological advances on the development of mobile devices, medical sensors, and wireless communication systems support a new generation of unobtrusive, portable, and ubiquitous health monitoring systems for continuous patient assessment and more personalized health care. There exist a growing number of mobile apps in the health domain; however, little contribution has been specifically provided, so far, to operate this kind of apps with wearable physiological sensors. The PhysioDroid, presented in this paper, provides a personalized means to remotely monitor and evaluate users' conditions. The PhysioDroid system provides ubiquitous and continuous vital signs analysis, such as electrocardiogram, heart rate, respiration rate, skin temperature, and body motion, intended to help empower patients and improve clinical understanding. The PhysioDroid is composed of a wearable monitoring device and an Android app providing gathering, storage, and processing features for the physiological sensor data. The versatility of the developed app allows its use for both average users and specialists, and the reduced cost of the PhysioDroid puts it at the reach of most people. Two exemplary use cases for health assessment and sports training are presented to illustrate the capabilities of the PhysioDroid. Next technical steps include generalization to other mobile platforms and health monitoring devices.

  8. Decoding the ubiquitous role of microRNAs in neurogenesis.

    PubMed

    Nampoothiri, Sreekala S; Rajanikant, G K

    2017-04-01

    Neurogenesis generates fledgling neurons that mature to form an intricate neuronal circuitry. The delusion on adult neurogenesis was far resolved in the past decade and became one of the largely explored domains to identify multifaceted mechanisms bridging neurodevelopment and neuropathology. Neurogenesis encompasses multiple processes including neural stem cell proliferation, neuronal differentiation, and cell fate determination. Each neurogenic process is specifically governed by manifold signaling pathways, several growth factors, coding, and non-coding RNAs. A class of small non-coding RNAs, microRNAs (miRNAs), is ubiquitously expressed in the brain and has emerged to be potent regulators of neurogenesis. It functions by fine-tuning the expression of specific neurogenic gene targets at the post-transcriptional level and modulates the development of mature neurons from neural progenitor cells. Besides the commonly discussed intrinsic factors, the neuronal morphogenesis is also under the control of several extrinsic temporal cues, which in turn are regulated by miRNAs. This review enlightens on dicer controlled switch from neurogenesis to gliogenesis, miRNA regulation of neuronal maturation and the differential expression of miRNAs in response to various extrinsic cues affecting neurogenesis.

  9. New Martian climate constraints from radar reflectivity within the north polar layered deposits

    NASA Astrophysics Data System (ADS)

    Lalich, D. E.; Holt, J. W.

    2017-01-01

    The north polar layered deposits (NPLD) of Mars represent a global climate record reaching back millions of years, potentially recorded in visible layers and radar reflectors. However, little is known of the specific link between those layers, reflectors, and the global climate. To test the hypothesis that reflectors are caused by thick and indurated layers known as "marker beds," the reflectivity of three reflectors was measured, mapped, and compared to a reflectivity model. The measured reflectivities match the model and show a strong sensitivity to layer thickness, implying that radar reflectivity may be used as a proxy for short-term accumulation patterns and that regional climate plays a strong role in layer thickness variations. Comparisons to an orbitally forced NPLD accumulation model show a strong correlation with predicted marker bed formation, but dust content is higher than expected, implying a stronger role for dust in Mars polar climate than previously thought.

  10. Sporadic E-Layers and Meteor Activity

    NASA Astrophysics Data System (ADS)

    Alimov, Obid

    2016-07-01

    In average width it is difficult to explain variety of particularities of the behavior sporadic layer Es ionospheres without attraction long-lived metallic ion of the meteoric origin. Mass spectrometric measurements of ion composition using rockets indicate the presence of metal ions Fe+, Mg+, Si+, Na+, Ca+, K+, Al+ and others in the E-region of the ionosphere. The most common are the ions Fe+, Mg+, Si+, which are primarily concentrated in the narrow sporadic layers of the ionosphere at altitudes of 90-130 km. The entry of meteoric matter into the Earth's atmosphere is a source of meteor atoms (M) and ions (M +) that later, together with wind shear, produce midlatitude sporadic Es layer of the ionosphere. To establish the link between sporadic Es layer and meteoroid streams, we proceeded from the dependence of the ionization coefficient of meteors b on the velocity of meteor particles in different meteoroid streams. We investigated the dependence of the critical frequency f0Es of sporadic E on the particle velocity V of meteor streams and associations. It was established that the average values of f0Es are directly proportional to the velocity V of meteor streams and associations, with the correlation coefficient of 0.53 < R < 0.74. Thus, the critical frequency of the sporadic layer Es increases with the increase of particle velocity V in meteor streams, which indicates the direct influence of meteor particles on ionization of the lower ionosphere and formation of long-lived metal atoms M and ions M+ of meteoric origin.

  11. Dynamical origins of the community structure of an online multi-layer society

    NASA Astrophysics Data System (ADS)

    Klimek, Peter; Diakonova, Marina; Eguíluz, Víctor M.; San Miguel, Maxi; Thurner, Stefan

    2016-08-01

    Social structures emerge as a result of individuals managing a variety of different social relationships. Societies can be represented as highly structured dynamic multiplex networks. Here we study the dynamical origins of the specific community structures of a large-scale social multiplex network of a human society that interacts in a virtual world of a massive multiplayer online game. There we find substantial differences in the community structures of different social actions, represented by the various layers in the multiplex network. Community sizes distributions are either fat-tailed or appear to be centered around a size of 50 individuals. To understand these observations we propose a voter model that is built around the principle of triadic closure. It explicitly models the co-evolution of node- and link-dynamics across different layers of the multiplex network. Depending on link and node fluctuation probabilities, the model exhibits an anomalous shattered fragmentation transition, where one layer fragments from one large component into many small components. The observed community size distributions are in good agreement with the predicted fragmentation in the model. This suggests that several detailed features of the fragmentation in societies can be traced back to the triadic closure processes.

  12. High-T(sub c) Edge-geometry SNS Weak Links on Silicon-on-sapphire Substrates

    NASA Technical Reports Server (NTRS)

    Hunt, B.; Foote, M.; Pike, W.; Barner, J.; Vasquez, R.

    1994-01-01

    High-quality superconductor/normal-metal/superconductor(SNS) edge-geometry weak links have been produced on silicon-on-sapphire (SOS) substrates using a new SrTiO(sub 3)/'seed layer'/cubic-zirconia (YS2) buffer system.

  13. The Fast-Paced iPad Revolution: Can Educators Stay up to Date and Relevant about These Ubiquitous Devices?

    ERIC Educational Resources Information Center

    Peluso, Deanna C. C.

    2012-01-01

    Stepping into a modern day classroom, one will find that it is filled with a ubiquitous array of multimodal and digital resources, yet a majority of these revolutionary resources are likely not school issued, rather they were brought by the young people themselves. Digital mediums for communication, expression and multimodally engaging in one's…

  14. Ubiquitous Health in Korea: Progress, Barriers, and Prospects

    PubMed Central

    Lee, Yountae

    2012-01-01

    Objectives Korea has one of the most advanced information technology (IT) infrastructures in the world, and the application of IT in health systems is rapidly progressing from computerization to information systems, ubiquitous systems, and smart systems. This study aims to analyze Korean environments in regards to the development of their u-Health industry and propose directions for u-Healthcare services based on this analysis. Methods This paper reviews the background, progress history, and current status of u-Health in Korea, and suggests strategies for the u-Health industry based on an analysis of its barriers and obstacles. Results When u-Health was introduced to Koreans, their policies and approaches focused mainly on environmental factors, yet these efforts have not progressed further to impact the u-Healthcare service industry itself. To develop the u-Healthcare industry, four points need to be considered: the development and support of the practical service model, institutional support, support of core technology and industry, and the institutionalization of health management service. Conclusions Korea is at a strategic point to start building u-Healthcare service delivery models. u-Healthcare is a healthcare service that provides added value through u-Health environments. By identifying critical success factors in u-Healthcare, we can strengthen the u-Health industry and implement policies to coordinate our efforts in the process of value chains to which we belong. PMID:23346474

  15. Transglutaminase catalyzed cross-linking of sodium caseinate improves oxidative stability of flaxseed oil emulsion.

    PubMed

    Ma, Hairan; Forssell, Pirkko; Kylli, Petri; Lampi, Anna-Maija; Buchert, Johanna; Boer, Harry; Partanen, Riitta

    2012-06-20

    Sodium caseinate was modified by transglutaminase catalyzed cross-linking reaction prior to the emulsification process in order to study the effect of cross-linking on the oxidative stability of protein stabilized emulsions. The extent of the cross-linking catalyzed by different dosages of transglutaminase was investigated by following the ammonia production during the reaction and using SDS-PAGE gel. O/W emulsions prepared with the cross-linked and non-cross-linked sodium caseinates were stored for 30 days under the same conditions. Peroxide value measurement, oxygen consumption measurement, and headspace gas chromatography analysis were used to study the oxidative stability of the emulsions. The emulsion made of the cross-linked sodium caseinate showed an improved oxidative stability with reduced formation of fatty acid hydroperoxides and volatiles and a longer period of low rate oxygen consumption. The improving effect of transglutaminase catalyzed cross-linking could be most likely attributed to the enhanced physical stability of the interfacial protein layer against competitive adsorption by oil oxidation products.

  16. Enhanced Column Filtration for Arsenic Removal from Water: Polymer-Templated Iron Oxide Nanoparticles Immobilized on Sand via Layer-by-Layer Deposition

    NASA Astrophysics Data System (ADS)

    Cheng, Calvin Chia-Hung

    Arsenic is ubiquitous in water sources around the world and is highly toxic. While precipitation and membrane filtration techniques are successfully implemented in developed cities, they are unsuitable for rural and low-resource settings lacking centralized facilities. This thesis presents the use of ultra-small iron oxide (Fe2O3) nanoparticles functionalized on sand granules for use as a house-hold scale adsorption filter. Water-stable alpha-Fe2O3 (hematite) nanoparticles (<10 nm) were synthesized via a collapsed-polymer approach using poly(acrylic acid) and Fe3+ ions. The nanoparticles exhibited high arsenic adsorption, with 147 +/- 2 mg As(III) per g Fe2O3 and 91 +/- 10 mg As(V) per g Fe2O3. The platform was also used to synthesize iron-based composites, including magnetite (Fe 3O4) and Fe-Cu oxide nanoparticles. For use as a column filter, Fe2O3-PAA nanoparticles were functionalized on sand granules using a layer-by-layer deposition method, with the nanoparticles embedded in the negative layer. The removal of As(III) by the Fe2O 3-PAA functionalized column was described by reversible 1st order kinetics where the forward and reverse rate constants were 0.31 hr -1 and 0.097 hr-1, respectively. Implemented as a passive water filter with 30 x 30 x 50 cm3 dimensions, the filter has an expected lifetime in the order of many years. By controlling the flow rate of the column depending on contamination levels, the filter effectively removes arsenic down to the safety limit of 0.01 mg/L. In a parallel project, the layer-by-layer deposition of Poly(diallydimethyl ammonium chloride) (PDDA) and poly(sodium 5-styrenesulfonate) (PSS) was exploited for a highly practical synthesis of discrete gradient surfaces. By independently controlling the concentration of NaCl in PDDA and PSS deposition solutions, a 2-dimensional matrix of surfaces was created in 96-well microtiter plates. Distinct non-monotonic dye adsorption patterns on the gradient surfaces was observed. Practical

  17. Fieldservers and Sensor Service Grid as Real-time Monitoring Infrastructure for Ubiquitous Sensor Networks

    PubMed Central

    Honda, Kiyoshi; Shrestha, Aadit; Witayangkurn, Apichon; Chinnachodteeranun, Rassarin; Shimamura, Hiroshi

    2009-01-01

    The fieldserver is an Internet based observation robot that can provide an outdoor solution for monitoring environmental parameters in real-time. The data from its sensors can be collected to a central server infrastructure and published on the Internet. The information from the sensor network will contribute to monitoring and modeling on various environmental issues in Asia, including agriculture, food, pollution, disaster, climate change etc. An initiative called Sensor Asia is developing an infrastructure called Sensor Service Grid (SSG), which integrates fieldservers and Web GIS to realize easy and low cost installation and operation of ubiquitous field sensor networks. PMID:22574018

  18. Investigation of Learning Behaviors and Achievement of Vocational High School Students Using an Ubiquitous Physics Tablet PC App

    ERIC Educational Resources Information Center

    Purba, Siska Wati Dewi; Hwang, Wu-Yuin

    2017-01-01

    In this study, we designed and developed an app called Ubiquitous-Physics (U-Physics) for mobile devices like tablet PC or smart phones to help students learn the principles behind a simple pendulum in Physics. The unique characteristic of U-Physics is the use of sensors on mobile devices to collect acceleration and velocity data during pendulum…

  19. Distinctive viscoelastic and viscoplastic nanomechanics of ionically cross-linked polyelectrolyte complexes under intermittent relaxation and creep

    NASA Astrophysics Data System (ADS)

    Han, Biao; Ma, Tianzhu; Lee, Daeyeon; Shenoy, Vivek; Han, Lin

    This study aims to reveal unique nanoscale viscoelastic and viscoplastic properties of ionically linked polyelectrolyte networks. Layer-by-layer PAH/PAA complexes were tested by four continuous loading cycles in aqueous solutions. In each cycle, AFM-nanoindentation via a microspherical tip (R =5 μm) was applied up to 1 μN force, followed by a 30-60 sec hold at either a constant indentation depth to measure relaxation, or a constant force to measure creep. At a highly cross-linked, net neutral state (0.01M, pH 5.5), instantaneous modulus increased by 2.7-fold from first to last cycle, while the degree of relaxation (>95%) remain consistent. These results indicate repeated loading increases local cross-link density, while relaxation is consistently dominated by cross-link breaking and re-formation. In contrast, under creep, modulus increased by a similar 3.5-fold, and degree of creep is significantly attenuated from ~50% to 45% from first to last cycle. Results from creep suggest constant viscous flow of polymer chains in the absence of permanent anchorage. As a result, an irreversible deformation (~370nm) was observed after multiple creep cycles, suggesting the presence of viscoplasticity.

  20. Wireless Visual Sensor Network Resource Allocation using Cross-Layer Optimization

    DTIC Science & Technology

    2009-01-01

    Rate Compatible Punctured Convolutional (RCPC) codes for channel...vol. 44, pp. 2943–2959, November 1998. [22] J. Hagenauer, “ Rate - compatible punctured convolutional codes (RCPC codes ) and their applications,” IEEE... coding rate for H.264/AVC video compression is determined. At the data link layer, the Rate - Compatible Puctured Convolutional (RCPC) channel coding

  1. An Internet-style Approach to Managing Wireless Link Errors

    DTIC Science & Technology

    2002-05-01

    implementation I used. Jamshid Mahdavi and Matt Mathis, then at the Pittsburgh Super- computer Center, and Vern Paxson of the Lawrence Berkeley National...Exposition. IEEE CS Press, 2002. [19] P. Bhagwat, P. Bhattacharya, A. Krishna , and S. Tripathi. Enhancing throughput over wireless LANs using channel...performance over wireless networks at the link layer. ACM Mobile Networks and Applications, 5(1):57– 71, March 2000. [97] Vern Paxson and Mark Allman

  2. Comparative Genomics of the Ubiquitous, Hydrocarbon-degrading Genus Marinobacter

    NASA Astrophysics Data System (ADS)

    Singer, E.; Webb, E.; Edwards, K. J.

    2012-12-01

    The genus Marinobacter is amongst the most ubiquitous in the global oceans and strains have been isolated from a wide variety of marine environments, including offshore oil-well heads, coastal thermal springs, Antarctic sea water, saline soils and associations with diatoms and dinoflagellates. Many strains have been recognized to be important hydrocarbon degraders in various marine habitats presenting sometimes extreme pH or salinity conditions. Analysis of the genome of M. aquaeolei revealed enormous adaptation versatility with an assortment of strategies for carbon and energy acquisition, sensation, and defense. In an effort to elucidate the ecological and biogeochemical significance of the Marinobacters, seven Marinobacter strains from diverse environments were included in a comparative genomics study. Genomes were screened for metabolic and adaptation potential to elucidate the strategies responsible for the omnipresence of the Marinobacter genus and their remedial action potential in hydrocarbon-polluted waters. The core genome predominantly encodes for key genes involved in hydrocarbon degradation, biofilm-relevant processes, including utilization of external DNA, halotolerance, as well as defense mechanisms against heavy metals, antibiotics, and toxins. All Marinobacter strains were observed to degrade a wide spectrum of hydrocarbon species, including aliphatic, polycyclic aromatic as well as acyclic isoprenoid compounds. Various genes predicted to facilitate hydrocarbon degradation, e.g. alkane 1-monooxygenase, appear to have originated from lateral gene transfer as they are located on gene clusters of 10-20% lower GC-content compared to genome averages and are flanked by transposases. Top ortholog hits are found in other hydrocarbon degrading organisms, e.g. Alcanivorax borkumensis. Strategies for hydrocarbon uptake encoded by various Marinobacter strains include cell surface hydrophobicity adaptation via capsular polysaccharide biosynthesis and attachment

  3. Ubiquitous Green Computing Techniques for High Demand Applications in Smart Environments

    PubMed Central

    Zapater, Marina; Sanchez, Cesar; Ayala, Jose L.; Moya, Jose M.; Risco-Martín, José L.

    2012-01-01

    Ubiquitous sensor network deployments, such as the ones found in Smart cities and Ambient intelligence applications, require constantly increasing high computational demands in order to process data and offer services to users. The nature of these applications imply the usage of data centers. Research has paid much attention to the energy consumption of the sensor nodes in WSNs infrastructures. However, supercomputing facilities are the ones presenting a higher economic and environmental impact due to their very high power consumption. The latter problem, however, has been disregarded in the field of smart environment services. This paper proposes an energy-minimization workload assignment technique, based on heterogeneity and application-awareness, that redistributes low-demand computational tasks from high-performance facilities to idle nodes with low and medium resources in the WSN infrastructure. These non-optimal allocation policies reduce the energy consumed by the whole infrastructure and the total execution time. PMID:23112621

  4. Ubiquitous green computing techniques for high demand applications in Smart environments.

    PubMed

    Zapater, Marina; Sanchez, Cesar; Ayala, Jose L; Moya, Jose M; Risco-Martín, José L

    2012-01-01

    Ubiquitous sensor network deployments, such as the ones found in Smart cities and Ambient intelligence applications, require constantly increasing high computational demands in order to process data and offer services to users. The nature of these applications imply the usage of data centers. Research has paid much attention to the energy consumption of the sensor nodes in WSNs infrastructures. However, supercomputing facilities are the ones presenting a higher economic and environmental impact due to their very high power consumption. The latter problem, however, has been disregarded in the field of smart environment services. This paper proposes an energy-minimization workload assignment technique, based on heterogeneity and application-awareness, that redistributes low-demand computational tasks from high-performance facilities to idle nodes with low and medium resources in the WSN infrastructure. These non-optimal allocation policies reduce the energy consumed by the whole infrastructure and the total execution time.

  5. iRAGu: A Novel Inducible and Reversible Mouse Model for Ubiquitous Recombinase Activity

    PubMed Central

    Bonnet, Marie; Sarmento, Leonor Morais; Martins, Ana C.; Sobral, Daniel; Silva, Joana; Demengeot, Jocelyne

    2017-01-01

    Developing lymphocytes express the recombination activating genes (RAGs) 1 and 2 products that form a site specific recombinase complex (RAG), introducing double strand DNA breaks (DSBs) at recombination signal sequences (RSSs) flanking the V, D, and J gene segments in the antigen receptor loci. The subsequent steps in the reaction consist in the ligation of DSBs by ubiquitous enzymes of the non-homologous end joining DNA repair pathway. This mutagenesis process is responsible for the generation of the very large clonal diversity of T and B lymphocytes, itself allowing the recognition of a virtually open-ended antigenic universe. Sequences resembling RSS are found at high frequency all over the genome, and involved in RAG mediated illegitimate recombination and translocations. Hence, natural and induced ectopic activity of RAG is a threat to the genome only recently underscored. Here, we report and characterize a novel mouse transgenic system for which ubiquitous expression of the recombinase is inducible. In this system, the RAG1 protein is constitutively expressed and functional, while the RAG2 protein, coupled to the estrogen receptor, becomes functionally active upon 4-hydroxytamoxifen (TAM) administration. We describe two transgenic lines. The first one, when introgressed into an endogenous Rag2−/− genetic background is faithfully recapitulating lymphocyte development, repertoire dynamics and cryptic rearrangements, in a TAM-dependent manner. In this model, deprivation of TAM is followed by lymphocyte development arrest, evidencing the reversibility of the system. The second transgenic line is leaky, as the transgenes promote lymphocyte differentiation in absence of TAM treatment. Upon TAM-induction defects in lymphocytes composition and global health reveals the deleterious effect of uncontrolled RAG activity. Overall, this novel transgenic model provides a tool where RAG activity can be specifically manipulated to assess the dynamics of lymphocyte

  6. Innovation in Layer-by-Layer Assembly.

    PubMed

    Richardson, Joseph J; Cui, Jiwei; Björnmalm, Mattias; Braunger, Julia A; Ejima, Hirotaka; Caruso, Frank

    2016-12-14

    Methods for depositing thin films are important in generating functional materials for diverse applications in a wide variety of fields. Over the last half-century, the layer-by-layer assembly of nanoscale films has received intense and growing interest. This has been fueled by innovation in the available materials and assembly technologies, as well as the film-characterization techniques. In this Review, we explore, discuss, and detail innovation in layer-by-layer assembly in terms of past and present developments, and we highlight how these might guide future advances. A particular focus is on conventional and early developments that have only recently regained interest in the layer-by-layer assembly field. We then review unconventional assemblies and approaches that have been gaining popularity, which include inorganic/organic hybrid materials, cells and tissues, and the use of stereocomplexation, patterning, and dip-pen lithography, to name a few. A relatively recent development is the use of layer-by-layer assembly materials and techniques to assemble films in a single continuous step. We name this "quasi"-layer-by-layer assembly and discuss the impacts and innovations surrounding this approach. Finally, the application of characterization methods to monitor and evaluate layer-by-layer assembly is discussed, as innovation in this area is often overlooked but is essential for development of the field. While we intend for this Review to be easily accessible and act as a guide to researchers new to layer-by-layer assembly, we also believe it will provide insight to current researchers in the field and help guide future developments and innovation.

  7. Matching layer for path loss reduction in ultra wideband implant communications.

    PubMed

    Chavez-Santiago, Raul; Khaleghi, Ali; Balasingham, Ilangko

    2014-01-01

    Real-time monitoring of various physiological signals is of utmost importance for the treatment of chronic conditions. Radio technology can enable real-time sensing and collection of physiological data to facilitate timely medication and early pre-hospital management of patients. This can be realized with the aid of implantable biomedical sensors with the capability to transmit wirelessly the collected information to an external unit for display and analysis. Currently, commercial wireless medical implantable sensors operate in frequencies below 1 GHz with narrowband signals. Recently, it has been demonstrated that ultra wideband (UWB) signals could be also used for the radio interface of these devices. However, establishing an implant communication link in the allocated UWB spectrum of 3.1-10.6 GHz is challenging. The attenuation of UWB signals propagating through biological tissues at these frequencies is high. Part of these path losses are caused by the impedance mismatch between the two propagation environments (i.e., air and biological tissues) that constitute an implant communication link. This mismatch results in inefficient power transmission of the radio waves. In this paper we propose the use of a layer of dielectric material that can be applied on the patient's skin. The permittivity value of this matching layer has to be chosen such that wave coupling is maximized. Through numerical simulations we determined the appropriate permittivity value of a matching layer for UWB implant communication links in the human thorax for 1-6 GHz. Path loss reduction of up to 10 dB can be obtained in this frequency band. These results can help improve the use of UWB signals for other in-body biomedical devices like the wireless capsule endoscope (WCE).

  8. Tailoring graphene layer-to-layer growth

    NASA Astrophysics Data System (ADS)

    Li, Yongtao; Wu, Bin; Guo, Wei; Wang, Lifeng; Li, Jingbo; Liu, Yunqi

    2017-06-01

    A layered material grown between a substrate and the upper layer involves complex interactions and a confined reaction space, representing an unusual growth mode. Here, we show multi-layer graphene domains grown on liquid or solid Cu by the chemical vapor deposition method via this ‘double-substrate’ mode. We demonstrate the interlayer-induced coupling effect on the twist angle in bi- and multi-layer graphene. We discover dramatic growth disunity for different graphene layers, which is explained by the ideas of a chemical ‘gate’ and a material transport process within a confined space. These key results lead to a consistent framework for understanding the dynamic evolution of multi-layered graphene flakes and tailoring the layer-to-layer growth for practical applications.

  9. Ubiquitous overexpression of Hey1 transcription factor leads to osteopenia and chondrocyte hypertrophy in bone.

    PubMed

    Salie, Rishard; Kneissel, Michaela; Vukevic, Mirko; Zamurovic, Natasa; Kramer, Ina; Evans, Glenda; Gerwin, Nicole; Mueller, Matthias; Kinzel, Bernd; Susa, Mira

    2010-03-01

    The transcription factor Hey1, a known Notch target gene of the HES family, has recently been described as a target gene of bone morphogenetic protein-2 (BMP-2) during osteoblastic differentiation in vitro. As the role of Hey1 in skeletal physiology is unknown, we analyzed bones of mice ubiquitously lacking or overexpressing Hey1. This strategy enabled us to evaluate whether Hey1 modulation in the whole organism could serve as a drug or antibody target for therapy of diseases associated with bone loss. Hey1 deficiency resulted in modest osteopenia in vivo and increased number and activity of osteoclasts generated ex vivo. Hey1 overexpression resulted in distinct progressive osteopenia and inhibition of osteoblasts ex vivo, an effect apparently dominant to a mild inhibition of osteoclasts. In both Hey1 deficient and overexpressing mice, males were less affected than females and skeleton was not affected during development. Bone histomorphometry did not reveal major changes in animals at 20 weeks, suggesting that modulation had occurred before. Adult Hey1 transgenics also displayed increased type X collagen expression and an enlarged hypertrophic zone in the growth plate. Taken together, our data suggest that ubiquitous in vivo Hey1 regulation affects osteoblasts, osteoclasts and chondrocytes. Due to the complex role of Hey1 in bone, inhibition of Hey1 does not appear to be a straightforward therapeutic strategy to increase the bone mass.

  10. The effect of nerve section on the incidence and distribution of gap junctions in the odontoblast layer of the cat.

    PubMed

    Holland, G R

    1987-08-01

    Gap junctions are numerous in the odontoblast layer of the dental pulp and may link sensory axons to odontoblasts. If these junctions do link axons and odontoblasts, they, together with the axons, should disappear after cutting the pulpal nerves centrally. Under general anesthesia the inferior alveolar nerve on one side of two young adult cats was sectioned. Under general anesthesia the animals were perfused with fixative 56 hours later and the coronal dental pulp prepared for electron microscopy. Ultrathin sections were examined from the level of the pulpal cornu and levels approximately one, two, and three mm below this. The incidence of cell processes and gap junctions was measured at different distances from the pulp predentin junction, and operated and control sides compared. The odontoblast layer at the level of the cornu differed from elsewhere in having, on the control side, a greater density of cell processes and gap junctions and in having clearly recognizable axons approaching to within 5 to 10 micron of the predentin. The only statistically significant changes after nerve section occurred in this layer and consisted of a decline in the incidence of cell processes and of gap junctions that link one cell process to another. There was no significant difference between the operated and control sides in the number of gap junctions linking cell processes to recognizable cell bodies. The odontoblast layer in the pulpal cornu contained substantial numbers of unsheathed axons, many presumably en route to the dentin. These axons may participate in gap junctions that link them to other cell processes, possibly even other axons.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Purification and characterization of Campylobacter rectus surface layer proteins.

    PubMed Central

    Nitta, H; Holt, S C; Ebersole, J L

    1997-01-01

    Campylobacter rectus is a putative periodontopathogen which expresses a proteinaceous surface layer (S-layer) external to the outer membrane. S-layers are considered to play a protective role for the microorganism in hostile environments. The S-layer proteins from six different C. rectus strains (five human isolates and a nonhuman primate [NHP] isolate) were isolated, purified, and characterized. The S-layer proteins of these strains varied in molecular mass (ca. 150 to 166 kDa) as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. They all reacted with monospecific rabbit antiserum to the purified S-layer of C. rectus 314, but a quantitative enzyme-linked immunosorbent assay demonstrated a strong antigenic relationship among the five human strains, while the NHP strain, 6250, showed weaker reactivity. Amino acid composition analysis showed that the S-layers of four C. rectus strains contained large proportions of acidic amino acids (13 to 27%) and that >34% of the amino acid residues were hydrophobic. Amino acid sequence analysis of six S-layer proteins revealed that the first 15 amino-terminal amino acids were identical and showed seven residues of identity with the amino-terminal sequence of the Campylobacter fetus S-layer protein SapA1. CNBr peptide profiles of the S-layer proteins from C. rectus 314, ATCC 33238, and 6250 confirmed that the S-layer proteins from the human strains were similar to each other and somewhat different from that of the NHP isolate (strain 6250). However, the S-layer proteins from the two human isolates do show some structural heterogeneity. For example, there was a 17-kDa fragment unique to the C. rectus 314 S-layer. The amino-terminal sequence of this peptide had homology with the C. rectus 51-kDa porin and was composed of nearly 50% hydrophobic residues. Thus, the S-layer protein from C. rectus has structural heterogeneity among different human strains and immunoheterogeneity with the NHP strain. PMID:9009300

  12. Development and Effectiveness Analysis of a Personalized Ubiquitous Multi-Device Certification Tutoring System Based on Bloom's Taxonomy of Educational Objectives

    ERIC Educational Resources Information Center

    Hwang, Gwo-Haur; Chen, Beyin; Huang, Cin-Wei

    2016-01-01

    In recent years, with the gradual increase in the importance of professional certificates, improvement in certification tutoring systems has become more important. In this study, we have developed a personalized ubiquitous multi-device certification tutoring system (PUMDCTS) based on "Bloom's Taxonomy of Educational Objectives," and…

  13. On the nonlinear three dimensional instability of Stokes layers and other shear layers to pairs of oblique waves

    NASA Technical Reports Server (NTRS)

    Wu, Xuesong; Lee, Sang Soo; Cowley, Stephen J.

    1992-01-01

    The nonlinear evolution of a pair of initially oblique waves in a high Reynolds Number Stokes layer is studied. Attention is focused on times when disturbances of amplitude epsilon have O(epsilon(exp 1/3)R) growth rates, where R is the Reynolds number. The development of a pair of oblique waves is then controlled by nonlinear critical-layer effects. Viscous effects are included by studying the distinguished scaling epsilon = O(R(exp -1)). This leads to a complicated modification of the kernel function in the integro-differential amplitude equation. When viscosity is not too large, solutions to the amplitude equation develop a finite-time singularity, indicating that an explosive growth can be introduced by nonlinear effects; we suggest that such explosive growth can lead to the bursts observed in experiments. Increasing the importance of viscosity generally delays the occurrence of the finite-time singularity, and sufficiently large viscosity may lead to the disturbance decaying exponentially. For the special case when the streamwise and spanwise wavenumbers are equal, the solution can evolve into a periodic oscillation. A link between the unsteady critical-layer approach to high-Reynolds-number flow instability, and the wave vortex approach is identified.

  14. Burning Graphene Layer-by-Layer

    PubMed Central

    Ermakov, Victor A.; Alaferdov, Andrei V.; Vaz, Alfredo R.; Perim, Eric; Autreto, Pedro A. S.; Paupitz, Ricardo; Galvao, Douglas S.; Moshkalev, Stanislav A.

    2015-01-01

    Graphene, in single layer or multi-layer forms, holds great promise for future electronics and high-temperature applications. Resistance to oxidation, an important property for high-temperature applications, has not yet been extensively investigated. Controlled thinning of multi-layer graphene (MLG), e.g., by plasma or laser processing is another challenge, since the existing methods produce non-uniform thinning or introduce undesirable defects in the basal plane. We report here that heating to extremely high temperatures (exceeding 2000 K) and controllable layer-by-layer burning (thinning) can be achieved by low-power laser processing of suspended high-quality MLG in air in “cold-wall” reactor configuration. In contrast, localized laser heating of supported samples results in non-uniform graphene burning at much higher rates. Fully atomistic molecular dynamics simulations were also performed to reveal details of oxidation mechanisms leading to uniform layer-by-layer graphene gasification. The extraordinary resistance of MLG to oxidation paves the way to novel high-temperature applications as continuum light source or scaffolding material. PMID:26100466

  15. Is hyperactivity ubiquitous in ADHD or dependent on environmental demands? Evidence from meta-analysis

    PubMed Central

    Kofler, Michael J.; Raiker, Joseph S.; Sarver, Dustin E.; Wells, Erica L.; Soto, Elia F.

    2016-01-01

    Hyperactivity, or excess gross motor activity, is considered a core and ubiquitous characteristic of ADHD. Alternate models question this premise, and propose that hyperactive behavior reflects, to a large extent, purposeful behavior to cope with environmental demands that interact with underlying neurobiological vulnerabilities. The present review critically evaluates the ubiquity and environmental modifiability of hyperactivity in ADHD through meta-analysis of 63 studies of mechanically measured activity level in children, adolescents, and adults with ADHD relative to typically developing (TD) groups. Random effects models corrected for publication bias confirmed elevated gross motor activity in ADHD (d = 0.86); surprisingly, neither participant age (child vs. adult) nor the proportion of each ADHD sample diagnosed with the Inattentive subtype/presentation moderated this effect. In contrast, activity level assessed during high cognitive load conditions in general (d = 1.14) and high executive functioning demands in particular (d = 1.39) revealed significantly higher effect sizes than activity level during low cognitive load (d = 0.36) and in-class schoolwork (d = 0.50) settings. Low stimulation environments, more rigorous diagnostic practices, actigraph measurement of movement frequency and intensity, and ADHD samples that included fewer females were also associated with larger effects. Overall, the results are inconsistent with DSM-5 and ADHD models that a) describe hyperactivity as ubiquitous behavior, b) predict a developmental decline in hyperactivity, or c) differentiate subtypes/presentations according to perceived differences in hyperactive behavior. Instead, results suggest that the presence and magnitude of hyperactive behavior in ADHD may be influenced to a considerable extent by environmental factors in general, and cognitive/executive functioning demands in particular. PMID:27131918

  16. Ubiquitous remote operation collaborative interface for MRI scanners

    NASA Astrophysics Data System (ADS)

    Morris, H. Douglas

    2001-05-01

    We have developed a remote control interface for research class magnetic resonance imaging (MRI) spectrometers. The goal of the interface is to provide a better collaborative environment for geographically dispersed researchers and a tool that can teach students of medical imaging in a network-based laboratory using state-of-the-art MR instrumentation that would not otherwise be available. The interface for the remote operator(s) is now ubiquitous web browser, which was chosen for the ease of controlling the operator interface, the display of both image and text information, and the wide availability on many computer platforms. The remote operator is presented with an active display in which they may select and control most of the parameters in the MRI experiment. The MR parameters are relayed via web browser to a CGI program running in a standard web server, which passes said parameters to the MRI manufacturers control software. The data returned to the operator(s) consists of the parameters used in acquiring that image, a flat 8-bit grayscale GIF representation of the image, and a 16-bit grayscale image that can be viewed by an appropriate application. It is obvious that the utility of this interface would be helpful for researchers of regional and national facilities to more closely collaborate with colleagues across their region, the nation, or the world. And medical imaging students can put much of their classroom discussions into practice on machinery that would not normally be available to them.

  17. From computers to ubiquitous computing by 2010: health care.

    PubMed

    Aziz, Omer; Lo, Benny; Pansiot, Julien; Atallah, Louis; Yang, Guang-Zhong; Darzi, Ara

    2008-10-28

    Over the past decade, miniaturization and cost reduction in semiconductors have led to computers smaller in size than a pinhead with powerful processing abilities that are affordable enough to be disposable. Similar advances in wireless communication, sensor design and energy storage have meant that the concept of a truly pervasive 'wireless sensor network', used to monitor environments and objects within them, has become a reality. The need for a wireless sensor network designed specifically for human body monitoring has led to the development of wireless 'body sensor network' (BSN) platforms composed of tiny integrated microsensors with on-board processing and wireless data transfer capability. The ubiquitous computing abilities of BSNs offer the prospect of continuous monitoring of human health in any environment, be it home, hospital, outdoors or the workplace. This pervasive technology comes at a time when Western world health care costs have sharply risen, reflected by increasing expenditure on health care as a proportion of gross domestic product over the last 20 years. Drivers of this rise include an ageing post 'baby boom' population, higher incidence of chronic disease and the need for earlier diagnosis. This paper outlines the role of pervasive health care technologies in providing more efficient health care.

  18. Ubiquitous radiogenic Os in Miocene to recent basalts from diverse mantle domains beneath the Colorado Plateau, USA

    NASA Astrophysics Data System (ADS)

    Schlieder, T.; Reid, M. R.; Widom, E.; Blichert-Toft, J.

    2015-12-01

    and/or layers [2]. Thus mafic magmatism associated with the CP appears to ubiquitously tap sources at least locally modified by processes such as recycling of ancient oceanic crust, introduction of terrigenous sediments, or subduction-related metasomatism. [1] Lee et al., Nature, 2001. [2] Carlson and Nowell, G-Cubed, 2001.

  19. Study of the ubiquitous hog farm system using wireless sensor networks for environmental monitoring and facilities control.

    PubMed

    Hwang, Jeonghwan; Yoe, Hyun

    2010-01-01

    Many hog farmers are now suffering from high pig mortality rates due to various wasting diseases and increased breeding costs, etc. It is therefore necessary for hog farms to implement systematic and scientific pig production technology to increase productivity and produce high quality pork in order to solve these problems. In this study, we describe such a technology by suggesting a ubiquitous hog farm system which applies WSN (Wireless Sensor Network) technology to the pig industry. We suggest that a WSN and CCTV (Closed-circuit television) should be installed on hog farms to collect environmental and image information which shall then help producers not only in monitoring the hog farm via the Web from outside the farm, but also facilitate the control of hog farm facilities in remote locations. In addition, facilities can be automatically controlled based on breeding environment parameters which are already set up and a SMS notice service to notify of deviations shall provide users with convenience. Hog farmers may increase production and improve pork quality through this ubiquitous hog farm system and prepare a database with information collected from environmental factors and the hog farm control devices, which is expected to provide information needed to design and implement suitable control strategies for hog farm operation.

  20. Study of the Ubiquitous Hog Farm System Using Wireless Sensor Networks for Environmental Monitoring and Facilities Control

    PubMed Central

    Hwang, Jeonghwan; Yoe, Hyun

    2010-01-01

    Many hog farmers are now suffering from high pig mortality rates due to various wasting diseases and increased breeding costs, etc. It is therefore necessary for hog farms to implement systematic and scientific pig production technology to increase productivity and produce high quality pork in order to solve these problems. In this study, we describe such a technology by suggesting a ubiquitous hog farm system which applies WSN (Wireless Sensor Network) technology to the pig industry. We suggest that a WSN and CCTV (Closed-circuit television) should be installed on hog farms to collect environmental and image information which shall then help producers not only in monitoring the hog farm via the Web from outside the farm, but also facilitate the control of hog farm facilities in remote locations. In addition, facilities can be automatically controlled based on breeding environment parameters which are already set up and a SMS notice service to notify of deviations shall provide users with convenience. Hog farmers may increase production and improve pork quality through this ubiquitous hog farm system and prepare a database with information collected from environmental factors and the hog farm control devices, which is expected to provide information needed to design and implement suitable control strategies for hog farm operation. PMID:22163497

  1. A Folksonomy-Based Guidance Mechanism for Context-Aware Ubiquitous Learning: A Case Study of Chinese Scenic Poetry Appreciation Activities

    ERIC Educational Resources Information Center

    Shih, Wen-Chung; Tseng, Shian-Shyong; Yang, Che-Ching; Lin, Chih-Yu; Liang, Tyne

    2012-01-01

    In this work ubiquitous learning technologies are applied to Chinese scenic poetry appreciation. A folksonomy-based approach is proposed to accumulate knowledge about poems and their corresponding scenic spots. A user can use a "Tagging" operation by a smart phone to associate a concept (a word, a phrase or a sentence) with a scenic…

  2. Link Investigation of IEEE 802.15.4 Wireless Sensor Networks in Forests

    PubMed Central

    Ding, Xingjian; Sun, Guodong; Yang, Gaoxiang; Shang, Xinna

    2016-01-01

    Wireless sensor networks are expected to automatically monitor the ecological evolution and wildlife habits in forests. Low-power links (transceivers) are often adopted in wireless sensor network applications, in order to save the precious sensor energy and then achieve long-term, unattended monitoring. Recent research has presented some performance characteristics of such low-power wireless links under laboratory or outdoor scenarios with less obstacles, and they have found that low-power wireless links are unreliable and prone to be affected by the target environment. However, there is still less understanding about how well the low-power wireless link performs in real-world forests and to what extent the complex in-forest surrounding environments affect the link performances. In this paper, we empirically evaluate the low-power links of wireless sensors in three typical different forest environments. Our experiment investigates the performance of the link layer compatible with the IEEE 802.15.4 standard and analyzes the variation patterns of the packet reception ratio (PRR), the received signal strength indicator (RSSI) and the link quality indicator (LQI) under diverse experimental settings. Some observations of this study are inconsistent with or even contradict prior results that are achieved in open fields or relatively clean environments and thus, provide new insights both into effectively evaluating the low-power wireless links and into efficiently deploying wireless sensor network systems in forest environments. PMID:27355957

  3. Link Investigation of IEEE 802.15.4 Wireless Sensor Networks in Forests.

    PubMed

    Ding, Xingjian; Sun, Guodong; Yang, Gaoxiang; Shang, Xinna

    2016-06-27

    Wireless sensor networks are expected to automatically monitor the ecological evolution and wildlife habits in forests. Low-power links (transceivers) are often adopted in wireless sensor network applications, in order to save the precious sensor energy and then achieve long-term, unattended monitoring. Recent research has presented some performance characteristics of such low-power wireless links under laboratory or outdoor scenarios with less obstacles, and they have found that low-power wireless links are unreliable and prone to be affected by the target environment. However, there is still less understanding about how well the low-power wireless link performs in real-world forests and to what extent the complex in-forest surrounding environments affect the link performances. In this paper, we empirically evaluate the low-power links of wireless sensors in three typical different forest environments. Our experiment investigates the performance of the link layer compatible with the IEEE 802.15.4 standard and analyzes the variation patterns of the packet reception ratio (PRR), the received signal strength indicator (RSSI) and the link quality indicator (LQI) under diverse experimental settings. Some observations of this study are inconsistent with or even contradict prior results that are achieved in open fields or relatively clean environments and thus, provide new insights both into effectively evaluating the low-power wireless links and into efficiently deploying wireless sensor network systems in forest environments.

  4. Implementing pharmacogenomics decision support across seven European countries: The Ubiquitous Pharmacogenomics (U-PGx) project.

    PubMed

    Blagec, Kathrin; Koopmann, Rudolf; Crommentuijn-van Rhenen, Mandy; Holsappel, Inge; van der Wouden, Cathelijne H; Konta, Lidija; Xu, Hong; Steinberger, Daniela; Just, Enrico; Swen, Jesse J; Guchelaar, Henk-Jan; Samwald, Matthias

    2018-02-09

    Clinical pharmacogenomics (PGx) has the potential to make pharmacotherapy safer and more effective by utilizing genetic patient data for drug dosing and selection. However, widespread adoption of PGx depends on its successful integration into routine clinical care through clinical decision support tools, which is often hampered by insufficient or fragmented infrastructures. This paper describes the setup and implementation of a unique multimodal, multilingual clinical decision support intervention consisting of digital, paper-, and mobile-based tools that are deployed across implementation sites in seven European countries participating in the Ubiquitous PGx (U-PGx) project. © The Author(s) 2018. Published by Oxford University Press on behalf of the American Medical Informatics Association.

  5. Atomic Layer Deposition of Metastable β-Fe 2 O 3 via Isomorphic Epitaxy for Photoassisted Water Oxidation

    DOE PAGES

    Emery, Jonathan D.; Schlepütz, Christian M.; Guo, Peijun; ...

    2014-12-09

    Here, we report the growth and photoelectrochemical (PEC) characterization of the uncommon bibyite phase of iron(III) oxide (β-Fe 2O 3) epitaxially stabilized via atomic layer deposition on an conductive, transparent, and isomorphic template (Sn-doped In 2O 3). Furthermore, as a photoanode, unoptimized β-Fe 2O 3 ultrathin films perform similarly to their ubiquitous α-phase (hematite) counterpart, but reveal a more ideal bandgap (1.8 eV), a ~0.1 V improved photocurrent onset potential, and longer wavelength (>600 nm) spectral response. Finally, stable operation under basic water oxidation justifies further exploration of this atypical phase and motivates the investigation of other unexplored metastable phasesmore » as new PEC materials.« less

  6. Accretionary lapilli, tektites, or concretions: the ubiquitous spherules of Meridiani Planum

    NASA Astrophysics Data System (ADS)

    DiGregorio, Barry E.

    2004-11-01

    One of the most enigmatic discoveries made by the NASA Mars Exploration Rover Opportunity (MER-B) at the Meridiani Planum landing site are the ubiquitous spherules referred to as "blueberries" by the science team. They cover the entire landing area and can be seen in every direction within view of the rover cameras. Subsequent analysis of a small grouping of the spherules laying on top of a rock outcrop by Mossbauer spectroscopy showed an intense hematite signature not found on the rock or in the surrounding basaltic soils. Spherules were also found attached to and embedded within sedimentary sulfate rock outcrops found at the landing area that have been determined by the MER science team as having been formed in an acidic liquid water environment. The appearance of most of the Meridiani spherules is strikingly similar to the morphology and size of terrestrial accretionary lapilli and show similarities to terrestrial tektites. Accretionary lapilli are spherical balls and fragments with a concentric layered structure that are formed by a variety of mechanisms including hydrovolcanic eruptions, geysers and large meteorite impacts in water. Tektites are glassy impact spherules that form as a result of large meteorite impacts and also seem apparent in some of the rover images. Tektites can be perfectly spherical or have teardrop and dumbbell shapes. A lack of a visible volcanic source capable of producing high volumes of accretionary lapilli as seen in the MER-B images, in combination with the strong spectral signature of hematite, that some of the spherules display, led the MER science team to favor a concretion hypothesis thus far. All of these types of spherules involve interaction of with surface water or ice to form. Problems exist in explaining how the Martian "concretions", if that is indeed what they are, are of such uniform size and have such a wide distribution. Evidence from Martian orbit and on the surface indicate that the Meridiani Planum landing ellipse

  7. Intensity and Passion: On Musical Experience, Layers of Meaning, and Stages

    ERIC Educational Resources Information Center

    Varkøy, Øivind; Westby, Inger Anne

    2014-01-01

    In this article, the authors link the discussion of differing musical experiences to Frede V. Nielsen's exploration of music as a multifarious universe of meaning, which, in encounter with the listener's receptive consciousness, presents different layers of musical meaning. The focal point of the article is that which Nielsen refers to…

  8. Mobile Learning as a Method of Ubiquitous Learning: Students' Attitudes, Readiness, and Possible Barriers to Implementation in Higher Education

    ERIC Educational Resources Information Center

    Alhassan, Riyadh

    2016-01-01

    The purpose of this study was to explore the attitudes and level of readiness, and possible barriers to implementing Mobile Learning as a part of ubiquitous learning. In addition, the study attempted to find out to what extent students are interested in mobile learning. It also aimed to answer the question regarding the readiness of college…

  9. Calcium/Calmodulin-dependent Protein Kinase II is a Ubiquitous Molecule in Human Long-term Memory Synaptic Plasticity: A Systematic Review

    PubMed Central

    Ataei, Negar; Sabzghabaee, Ali Mohammad; Movahedian, Ahmad

    2015-01-01

    Background: Long-term memory is based on synaptic plasticity, a series of biochemical mechanisms include changes in structure and proteins of brain's neurons. In this article, we systematically reviewed the studies that indicate calcium/calmodulin kinase II (CaMKII) is a ubiquitous molecule among different enzymes involved in human long-term memory and the main downstream signaling pathway of long-term memory. Methods: All of the observational, case–control and review studies were considered and evaluated by the search engines PubMed, Cochrane Central Register of Controlled Trials and ScienceDirect Scopus between 1990 and February 2015. We did not carry out meta-analysis. Results: At the first search, it was fined 1015 articles which included “synaptic plasticity” OR “neuronal plasticity” OR “synaptic density” AND memory AND “molecular mechanism” AND “calcium/calmodulin-dependent protein kinase II” OR CaMKII as the keywords. A total of 335 articles were duplicates in the databases and eliminated. A total of 680 title articles were evaluated. Finally, 40 articles were selected as reference. Conclusions: The studies have shown the most important intracellular signal of long-term memory is calcium-dependent signals. Calcium linked calmodulin can activate CaMKII. After receiving information for learning and memory, CaMKII is activated by Glutamate, the most important neurotransmitter for memory-related plasticity. Glutamate activates CaMKII and it plays some important roles in synaptic plasticity modification and long-term memory. PMID:26445635

  10. Spin-Selective Transmission and Devisable Chirality in Two-Layer Metasurfaces.

    PubMed

    Li, Zhancheng; Liu, Wenwei; Cheng, Hua; Chen, Shuqi; Tian, Jianguo

    2017-08-15

    Chirality is a nearly ubiquitous natural phenomenon. Its minute presence in most naturally occurring materials makes it incredibly difficult to detect. Recent advances in metasurfaces indicate that they exhibit devisable chirality in novel forms; this finding offers an effective opening for studying chirality and its features in such nanostructures. These metasurfaces display vast possibilities for highly sensitive chirality discrimination in biological and chemical systems. Here, we show that two-layer metasurfaces based on twisted nanorods can generate giant spin-selective transmission and support engineered chirality in the near-infrared region. Two designed metasurfaces with opposite spin-selective transmission are proposed for treatment as enantiomers and can be used widely for spin selection and enhanced chiral sensing. Specifically, we demonstrate that the chirality in these proposed metasurfaces can be adjusted effectively by simply changing the orientation angle between the twisted nanorods. Our results offer simple and straightforward rules for chirality engineering in metasurfaces and suggest intriguing possibilities for the applications of such metasurfaces in spin optics and chiral sensing.

  11. The missing link: leadership, identity, and the social brain.

    PubMed

    van Vugt, Mark

    2012-05-01

    How the cohesion of a social network is being maintained in spite of having different layers of social interaction is an important question. I argue that the evolution of both (political) hierarchy and social identity play a crucial role in scaling up and bonding social networks. Together they are missing links in the social brain hypothesis, and further research is needed to understand the functions of leadership and social identity. ©2011 The British Psychological Society.

  12. Light penetration structures the deep acoustic scattering layers in the global ocean.

    PubMed

    Aksnes, Dag L; Røstad, Anders; Kaartvedt, Stein; Martinez, Udane; Duarte, Carlos M; Irigoien, Xabier

    2017-05-01

    The deep scattering layer (DSL) is a ubiquitous acoustic signature found across all oceans and arguably the dominant feature structuring the pelagic open ocean ecosystem. It is formed by mesopelagic fishes and pelagic invertebrates. The DSL animals are an important food source for marine megafauna and contribute to the biological carbon pump through the active flux of organic carbon transported in their daily vertical migrations. They occupy depths from 200 to 1000 m at daytime and migrate to a varying degree into surface waters at nighttime. Their daytime depth, which determines the migration amplitude, varies across the global ocean in concert with water mass properties, in particular the oxygen regime, but the causal underpinning of these correlations has been unclear. We present evidence that the broad variability in the oceanic DSL daytime depth observed during the Malaspina 2010 Circumnavigation Expedition is governed by variation in light penetration. We find that the DSL depth distribution conforms to a common optical depth layer across the global ocean and that a correlation between dissolved oxygen and light penetration provides a parsimonious explanation for the association of shallow DSL distributions with hypoxic waters. In enhancing understanding of this phenomenon, our results should improve the ability to predict and model the dynamics of one of the largest animal biomass components on earth, with key roles in the oceanic biological carbon pump and food web.

  13. Software Modules for the Proximity-1 Space Link Interleaved Time Synchronization (PITS) Protocol

    NASA Technical Reports Server (NTRS)

    Woo, Simon S.; Veregge, John R.; Gao, Jay L.; Clare, Loren P.; Mills, David

    2012-01-01

    The Proximity-1 Space Link Interleaved Time Synchronization (PITS) protocol provides time distribution and synchronization services for space systems. A software prototype implementation of the PITS algorithm has been developed that also provides the test harness to evaluate the key functionalities of PITS with simulated data source and sink. PITS integrates time synchronization functionality into the link layer of the CCSDS Proximity-1 Space Link Protocol. The software prototype implements the network packet format, data structures, and transmit- and receive-timestamp function for a time server and a client. The software also simulates the transmit and receive-time stamp exchanges via UDP (User Datagram Protocol) socket between a time server and a time client, and produces relative time offsets and delay estimates.

  14. Migration to Broadband and Ubiquitous Environments by Using Fiber-Optic Technologies in Access/Home Areas

    NASA Astrophysics Data System (ADS)

    Oguchi, Kimio

    2016-03-01

    The recent dramatic advances in information and communication technologies have yielded new environments. However, adoption still differs area by area. To realize the future broadband environment that everyone can enjoy everywhere, several technical issues have to be resolved before network penetration becomes ubiquitous. One such key is the use of fiber optics for the home and mobile services. This article overviews initial observations drawn from numerical survey data gathered over the last decade in several countries/regions, and gives some example scenarios for network/service evolution. One result implies that implementing new/future services must consider the gross domestic product impact.

  15. The ubiquitous PM component Zn2+ induces HO-1 expression through multiple targets in the Nrf2/Keap1 signaling pathway

    EPA Science Inventory

    Oxidant stress can play an important role in particulate matter (PM)–mediated toxicity in the respiratory tract. Zinc (Zn2+) is a ubiquitous component of ambient PM that induces adverse responses such as inflammatory and adaptive gene expression in human airway epithelial c...

  16. Investigating the link between imipenem resistance and biofilm formation by Pseudomonas aeruginosa.

    PubMed

    Musafer, Hadeel K; Kuchma, Sherry L; Naimie, Amanda A; Schwartzman, Joseph D; Al-Mathkhury, Harith J Fahad; O'Toole, George A

    2014-07-01

    Pseudomonas aeruginosa, a ubiquitous environmental organism, is a difficult-to-treat opportunistic pathogen due to its broad-spectrum antibiotic resistance and its ability to form biofilms. In this study, we investigate the link between resistance to a clinically important antibiotic, imipenem, and biofilm formation. First, we observed that the laboratory strain P. aeruginosa PAO1 carrying a mutation in the oprD gene, which confers resistance to imipenem, showed a modest reduction in biofilm formation. We also observed an inverse relationship between imipenem resistance and biofilm formation for imipenem-resistant strains selected in vitro, as well as for clinical isolates. We identified two clinical isolates of P. aeruginosa from the sputum of cystic fibrosis patients that formed robust biofilms, but were sensitive to imipenem (MIC ≤ 2 μg/ml). To test the hypothesis that there is a general link between imipenem resistance and biofilm formation, we performed transposon mutagenesis of these two clinical strains to identify mutants defective in biofilm formation, and then tested these mutants for imipenem resistance. Analysis of the transposon mutants revealed a role for previously described biofilm factors in these clinical isolates of P. aeruginosa, including mutations in the pilY1, pilX, pilW, algC, and pslI genes, but none of the biofilm-deficient mutants became imipenem resistant (MIC ≥ 8 μg/ml), arguing against a general link between biofilm formation and resistance to imipenem. Thus, assessing biofilm formation capabilities of environmental isolates is unlikely to serve as a good predictor of imipenem resistance. We also discuss our findings in light of the limited literature addressing planktonic antibiotic resistance factors that impact biofilm formation.

  17. Monolithic optical link in silicon-on-insulator CMOS technology.

    PubMed

    Dutta, Satadal; Agarwal, Vishal; Hueting, Raymond J E; Schmitz, Jurriaan; Annema, Anne-Johan

    2017-03-06

    This work presents a monolithic laterally-coupled wide-spectrum (350 nm < λ < 1270 nm) optical link in a silicon-on-insulator CMOS technology. The link consists of a silicon (Si) light-emitting diode (LED) as the optical source and a Si photodiode (PD) as the detector; both realized by vertical abrupt n+p junctions, separated by a shallow trench isolation composed of silicon dioxide. Medium trench isolation around the devices along with the buried oxide layer provides galvanic isolation. Optical coupling in both avalanche-mode and forward-mode operation of the LED are analyzed for various designs and bias conditions. From both DC and pulsed transient measurements, it is further shown that heating in the avalanche-mode LED leads to a slow thermal coupling to the PD with time constants in the ms range. An integrated heat sink in the same technology leads to a ∼ 6 times reduction in the change in PD junction temperature per unit electrical power dissipated in the avalanche-mode LED. The analysis paves way for wide-spectrum optical links integrated in smart power technologies.

  18. Layering and Ordering in Electrochemical Double Layers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Yihua; Kawaguchi, Tomoya; Pierce, Michael S.

    Electrochemical double layers (EDL) form at electrified interfaces. While Gouy-Chapman model describes moderately charged EDL, formation of Stern layers was predicted for highly charged EDL. Our results provide structural evidence for a Stern layer of cations, at potentials close to hydrogen evolution in alkali fluoride and chloride electrolytes. Layering was observed by x-ray crystal truncation rods and atomic-scale recoil responses of Pt(111) surface layers. Ordering in the layer is confirmed by glancing-incidence in-plane diffraction measurements.

  19. 3D Realistic Modeling of the Interaction of Quiet-Sun Magnetic Fields with the Chromosphere

    NASA Technical Reports Server (NTRS)

    Kitiashvili, I. N.; Kosovichev, A. G.; Mansour, N. N.; Wray, A. A.

    2017-01-01

    High-resolution observations and 3D simulations suggest that a local dynamo operates near the surface and produces ubiquitous small-scale magnetic elements, thus contributing to the magnetic carpet in the photosphere and to the magnetic structure and dynamics of the solar atmosphere. It appears that the traditional mechanisms of chromospheric energy and mass transport by acoustic waves and shocks are likely to play a secondary role; instead, the primary drivers in the energetics and dynamics of the chromosphere and transition region are small-scale, previously unresolved, quiet-Sun magnetic fields. These fields appear as ubiquitous, rapidly changing (on the scale of a few seconds), tiny magnetic loops and magnetized vortex tubes. Questions then arise about their origin and dynamics in the chromosphere, their links to magnetic fields in the photosphere, and their role in the energy storage and exchange between subsurface layers and the chromosphere. In the talk we will present results of 3D radiative MHD simulations obtained with the StellarBox code and discuss the energetics and dynamical interlinks between the subphotospheric layers and low chromosphere, their effects on the structure of the chromosphere, and signatures of the fine-scale magnetic features in high-resolution spectro-polarimetric observations.

  20. Design and Implementation of Davis Social Links OSN Kernel

    NASA Astrophysics Data System (ADS)

    Tran, Thomas; Chan, Kelcey; Ye, Shaozhi; Bhattacharyya, Prantik; Garg, Ankush; Lu, Xiaoming; Wu, S. Felix

    Social network popularity continues to rise as they broaden out to more users. Hidden away within these social networks is a valuable set of data that outlines everyone’s relationships. Networks have created APIs such as the Facebook Development Platform and OpenSocial that allow developers to create applications that can leverage user information. However, at the current stage, the social network support for these new applications is fairly limited in its functionality. Most, if not all, of the existing internet applications such as email, BitTorrent, and Skype cannot benefit from the valuable social network among their own users. In this paper, we present an architecture that couples two different communication layers together: the end2end communication layer and the social context layer, under the Davis Social Links (DSL) project. Our proposed architecture attempts to preserve the original application semantics (i.e., we can use Thunderbird or Outlook, unmodified, to read our SMTP emails) and provides the communicating parties (email sender and receivers) a social context for control and management. For instance, the receiver can set trust policy rules based on the social context between the pair, to determine how a particular email in question should be prioritized for delivery to the SMTP layer. Furthermore, as our architecture includes two coupling layers, it is then possible, as an option, to shift some of the services from the original applications into the social context layer. In the context of email, for example, our architecture allows users to choose operations, such as reply, reply-all, and forward, to be realized in either the application layer or the social network layer. And, the realization of these operations under the social network layer offers powerful features unavailable in the original applications. To validate our coupling architecture, we have implemented a DSL kernel prototype as a Facebook application called CyrusDSL (currently about

  1. PHY-DLL dialogue: cross-layer design for optical-wireless OFDM downlink transmission

    NASA Astrophysics Data System (ADS)

    Wang, Xuguo; Li, Lee

    2005-11-01

    The use of radio over fiber to provide radio access has a number of advantages including the ability to deploy small, low-cost remote antenna units and ease of upgrade. And due to the great potential for increasing the capacity and quality of service, the combination of Orthogonal Frequency Division Multiplexing (OFDM) modulation and the sub-carrier multiplexed optical transmission is one of the best solutions for the future millimeter-wave mobile communication. And this makes the optimum utility of valuable radio resources essential. This paper devises a cross-layer adaptive algorithm for optical-wireless OFDM system, which takes into consideration not only transmission power limitation in the physical layer, but also traffic scheduling and user fairness at the data-link layer. According to proportional fairness principle and water-pouring theorem, we put forward the complete description of this cross-layer adaptive downlink transmission 6-step algorithm. Simulation results show that the proposed cross-layer algorithm outperforms the mere physical layer adaptive algorithm markedly. The novel scheme is able to improve performance of the packet success rate per time chip and average packet delay, support added active users.

  2. Preserved number of entorhinal cortex layer II neurons in aged macaque monkeys

    NASA Technical Reports Server (NTRS)

    Gazzaley, A. H.; Thakker, M. M.; Hof, P. R.; Morrison, J. H.; Bloom, F. E. (Principal Investigator)

    1997-01-01

    The perforant path, which consists of the projection from the layer II neurons of the entorhinal cortex to the outer molecular layer of the dentate gyrus, is a critical circuit involved in learning and memory formation. Accordingly, disturbances in this circuit may contribute to age-related cognitive deficits. In a previous study, we demonstrated a decrease in N-methyl-D-aspartate receptor subunit 1 immunofluorescence intensity in the outer molecular layer of aged macaque monkeys. In this study, we used the optical fractionator, a stereological method, to determine if a loss of layer II neurons occurred in the same animals in which the N-methyl-D-aspartate receptor subunit 1 alteration was observed. Our results revealed no significant differences in the number of layer II neurons between juvenile, young adult, and aged macaque monkeys. These results suggest that the circuit-specific decrease in N-methyl-D-aspartate receptor subunit 1 reported previously occurs in the absence of structural compromise of the perforant path, and thus may be linked to an age-related change in the physiological properties of this circuit.

  3. Investigation on iterative multiuser detection physical layer network coding in two-way relay free-space optical links with turbulences and pointing errors.

    PubMed

    Abu-Almaalie, Zina; Ghassemlooy, Zabih; Bhatnagar, Manav R; Le-Minh, Hoa; Aslam, Nauman; Liaw, Shien-Kuei; Lee, It Ee

    2016-11-20

    Physical layer network coding (PNC) improves the throughput in wireless networks by enabling two nodes to exchange information using a minimum number of time slots. The PNC technique is proposed for two-way relay channel free space optical (TWR-FSO) communications with the aim of maximizing the utilization of network resources. The multipair TWR-FSO is considered in this paper, where a single antenna on each pair seeks to communicate via a common receiver aperture at the relay. Therefore, chip interleaving is adopted as a technique to separate the different transmitted signals at the relay node to perform PNC mapping. Accordingly, this scheme relies on the iterative multiuser technique for detection of users at the receiver. The bit error rate (BER) performance of the proposed system is examined under the combined influences of atmospheric loss, turbulence-induced channel fading, and pointing errors (PEs). By adopting the joint PNC mapping with interleaving and multiuser detection techniques, the BER results show that the proposed scheme can achieve a significant performance improvement against the degrading effects of turbulences and PEs. It is also demonstrated that a larger number of simultaneous users can be supported with this new scheme in establishing a communication link between multiple pairs of nodes in two time slots, thereby improving the channel capacity.

  4. Effects of the Team Competition-Based Ubiquitous Gaming Approach on Students' Interactive Patterns, Collective Efficacy and Awareness of Collaboration and Communication

    ERIC Educational Resources Information Center

    Chen, Chih-Hung; Hwang, Gwo-Jen

    2017-01-01

    Previous research has illustrated the importance of acquiring knowledge from authentic contexts; however, without full engagement, students' learning performance might not be as good as expected. In this study, a Team Competition-based Ubiquitous Gaming approach was proposed for improving students' learning effectiveness in authentic learning…

  5. CuGaS₂ and CuGaS₂-ZnS Porous Layers from Solution-Processed Nanocrystals.

    PubMed

    Berestok, Taisiia; Guardia, Pablo; Estradé, Sònia; Llorca, Jordi; Peiró, Francesca; Cabot, Andreu; Brock, Stephanie L

    2018-04-05

    The manufacturing of semiconducting films using solution-based approaches is considered a low cost alternative to vacuum-based thin film deposition strategies. An additional advantage of solution processing methods is the possibility to control the layer nano/microstructure. Here, we detail the production of mesoporous CuGaS₂ (CGS) and ZnS layers from spin-coating and subsequent cross-linking through chalcogen-chalcogen bonds of properly functionalized nanocrystals (NCs). We further produce NC-based porous CGS/ZnS bilayers and NC-based CGS-ZnS composite layers using the same strategy. Photoelectrochemical measurements are used to demonstrate the efficacy of porous layers, and particularly the CGS/ZnS bilayers, for improved current densities and photoresponses relative to denser films deposited from as-produced NCs.

  6. Development and Evaluation of Transgenic Nude Mice Expressing Ubiquitous Green Fluorescent Protein.

    PubMed

    Iyer, Srikanth; Arindkar, Shailendra; Mishra, Alaknanda; Manglani, Kapil; Kumar, Jerald Mahesh; Majumdar, Subeer S; Upadhyay, Pramod; Nagarajan, Perumal

    2015-08-01

    Researchers had developed and characterized transgenic green/red fluorescent protein (GFP/RFP) nude mouse with ubiquitous RFP or GFP expression, but none has evaluated the level of immune cells and expression levels of GFP in this model. The nude GFP mice were evaluated by imaging, hematological indices, and flow cytometry to compare the proportion of immune T cells. Quantitative real-time PCR (qRT-PCR) was done for evaluating the relative expression of GFP transcripts in few organs of the nude GFP mice. The hematological and immune cells of nude GFP were within the range of nude mice. However, the gene expression levels were relatively less in various tissues compared with B6 GFP mice. These findings suggest that nude GFP is an ideal model resembling normal nude mice; however, GFP expression in various tissues by fluorescence should be considered, as the expression of GFP differs in various organs.

  7. SUPAR: Smartphone as a ubiquitous physical activity recognizer for u-healthcare services.

    PubMed

    Fahim, Muhammad; Lee, Sungyoung; Yoon, Yongik

    2014-01-01

    Current generation smartphone can be seen as one of the most ubiquitous device for physical activity recognition. In this paper we proposed a physical activity recognizer to provide u-healthcare services in a cost effective manner by utilizing cloud computing infrastructure. Our model is comprised on embedded triaxial accelerometer of the smartphone to sense the body movements and a cloud server to store and process the sensory data for numerous kind of services. We compute the time and frequency domain features over the raw signals and evaluate different machine learning algorithms to identify an accurate activity recognition model for four kinds of physical activities (i.e., walking, running, cycling and hopping). During our experiments we found Support Vector Machine (SVM) algorithm outperforms for the aforementioned physical activities as compared to its counterparts. Furthermore, we also explain how smartphone application and cloud server communicate with each other.

  8. Tuning the overlap and the cross-layer correlations in two-layer networks: Application to a susceptible-infectious-recovered model with awareness dissemination

    NASA Astrophysics Data System (ADS)

    Juher, David; Saldaña, Joan

    2018-03-01

    We study the properties of the potential overlap between two networks A ,B sharing the same set of N nodes (a two-layer network) whose respective degree distributions pA(k ) ,pB(k ) are given. Defining the overlap coefficient α as the Jaccard index, we prove that α is very close to 0 when A and B are random and independently generated. We derive an upper bound αM for the maximum overlap coefficient permitted in terms of pA(k ) , pB(k ) , and N . Then we present an algorithm based on cross rewiring of links to obtain a two-layer network with any prescribed α inside the range (0 ,αM) . A refined version of the algorithm allows us to minimize the cross-layer correlations that unavoidably appear for values of α beyond a critical overlap αc<αM . Finally, we present a very simple example of a susceptible-infectious-recovered epidemic model with information dissemination and use the algorithms to determine the impact of the overlap on the final outbreak size predicted by the model.

  9. Null alleles are ubiquitous at microsatellite loci in the Wedge Clam (Donax trunculus)

    PubMed Central

    Cuesta, Jose Antonio; Drake, Pilar; Macpherson, Enrique; Bernatchez, Louis

    2017-01-01

    Recent studies have reported an unusually high frequency of nonamplifying alleles at microsatellite loci in bivalves. Null alleles have been associated with heterozygous deficits in many studies. While several studies have tested for its presence using different analytical tools, few have empirically tested for its consequences in estimating population structure and differentiation. We characterised 16 newly developed microsatellite loci and show that null alleles are ubiquitous in the wedge clam, Donax trunculus. We carried out several tests to demonstrate that the large heterozygous deficits observed in the newly characterised loci were most likely due to null alleles. We tested the robustness of microsatellite genotyping for population assignment by showing that well-recognised biogeographic regions of the south Atlantic and south Mediterranean coast of Spain harbour genetically different populations. PMID:28439464

  10. Engendering Long-Term Air and Light Stability of a TiO2-Supported Porphyrinic Dye via Atomic Layer Deposition.

    PubMed

    Hoffeditz, William L; Son, Ho-Jin; Pellin, Michael J; Farha, Omar K; Hupp, Joseph T

    2016-12-21

    Organic and porphyrin-based chromophores are prevalent in liquid-junction photovoltaic and photocatalytic solar-cell chemistry; however, their long-term air and light instability may limit their practicality in real world technologies. Here, we describe the protection of a zinc porphyrin dye, adsorbed on nanoparticulate TiO 2 , from air and light degradation by a protective coating of alumina grown with a previously developed post-treatment atomic layer deposition (ALD) technique. The protective Al 2 O 3 ALD layer is deposited using dimethylaluminum isopropoxide as an Al source; in contrast to the ubiquitous ALD precursor trimethylaluminum, dimethylaluminum isopropoxide does not degrade the zinc porphyrin dye, as confirmed by UV-vis measurements. The growth of this protective ALD layer around the dye can be monitored by an in-reactor quartz crystal microbalance (QCM). Furthermore, greater than 80% of porphyrin light absorption is retained over ∼1 month of exposure to air and light when the protective coating is present, whereas almost complete loss of porphyrin absorption is observed in less than 2 days in the absence of the ALD protective layer. Applying the Al 2 O 3 post-treatment technique to the TiO 2 -adsorbed dye allows the dye to remain in electronic contact with both the semiconductor surface and a surrounding electrolyte solution, the combination of which makes this technique promising for numerous other electrochemical photovoltaic and photocatalytic applications, especially those involving the dye-sensitized evolution of oxygen.

  11. Ionic liquids in a poly ethylene oxide cross-linked gel polymer as an electrolyte for electrical double layer capacitor

    NASA Astrophysics Data System (ADS)

    Chaudoy, V.; Tran Van, F.; Deschamps, M.; Ghamouss, F.

    2017-02-01

    In the present work, we developed a gel polymer electrolyte via the incorporation of a room temperature ionic liquid into a cross-linked polymer matrix. The cross-linked gel electrolyte was prepared using a free radical polymerization of methacrylate and dimethacrylate oligomers dissolved in 1-propyl-1-methylpyrrolidinium bis(fluorosulfonyl)imide. Combining the advantages of the ionic liquids and of conventional polymers, the cross-linked gel polymer electrolyte was used both as a separator and as an electrolyte for a leakage-free and non-flammable EDLC supercapacitor. The quasi-all solid-state supercapacitors showed rather good capacitance, power and energy densities by comparison to a liquid electrolyte-based EDLC.

  12. Experimental Findings from Aircraft Measurements in the Residual Layer

    NASA Astrophysics Data System (ADS)

    Caputi, D.; Conley, S. A.; Faloona, I. C.; Trousdell, J.

    2016-12-01

    The southern San Joaquin Valley of California is home to some of the highest ozone pollution in the United States. Thus, a complete understanding of boundary layer dynamics in this area during high ozone events is crucial for better ozone forecasting and effective attainment planning. This work will discuss the results from five aircraft deployments, spanning two summers, in which a Mooney aircraft operated by Scientific Aviation Inc. was flown between Fresno and Bakersfield throughout the diurnal cycle, measuring ozone, NOx, and methane. Under a simple budgeting model, changes in any species within the boundary layer can occur from advection, chemical production or loss, surface fluxes or deposition, and entrainment between the boundary layer and free troposphere. The advection of ozone appears to be most appreciable at night with stronger winds in the residual layer, and are on the order of 2 to 4 ppb hr-1. The nighttime chemical loss of ozone due to interaction with NO2 can be estimated by simple numerical modeling of observed quantities and reaction rates, and is found to often roughly compensate for the advection, with typical calculated values of -1 to -3 ppb hr-1. The mixing component is more difficult to directly quantify, but attempts are being made to estimate eddy viscosity by solving for this term in the budget equation. Additionally, small-scale features, such as nocturnal elevated mixed layers, localized BRN (bulk Richardson number) minimums, and low level jets are spotted in systematic ways throughout the flight data, and it is speculated that these may have a role in the transfer of ozone from the residual layer to the surface layer. Ultimately, the preliminary data is promising for the eventual goal of linking together the observed boundary layer evolution with ozone production during air pollution episodes.

  13. Ubiquitous Stereo Vision for Controlling Safety on Platforms in Railroad Station

    NASA Astrophysics Data System (ADS)

    Yoda, Ikushi; Hosotani, Daisuke; Sakaue, Katushiko

    Dozens of people are killed every year when they fall off of train platforms, making this an urgent issue to be addressed by the railroads, especially in the major cities. This concern prompted the present work that is now in progress to develop a Ubiquitous Stereo Vision based system for safety management at the edge of rail station platforms. In this approach, a series of stereo cameras are installed in a row on the ceiling that are pointed downward at the edge of the platform to monitor the disposition of people waiting for the train. The purpose of the system is to determine automatically and in real-time whether anyone or anything is in the danger zone at the very edge of the platform, whether anyone has actually fallen off the platform, or whether there is any sign of these things happening. The system could be configured to automatically switch over to a surveillance monitor or automatically connect to an emergency brake system in the event of trouble.

  14. Investigating the Modification of Spontaneous Emission using Layer-by-Layer Self-Assembly

    NASA Astrophysics Data System (ADS)

    Ashry, Islam Ahmed Ibrahim Youssef

    The process of spontaneous emission can be dramatically modified by optical micro- and nanostructures. We studied the modification of fluorescence dynamics using a polymer spacer layer fabricated through layer-by-layer (LbL) self-assembly. The advantages of this method are numerous: The self-assembled spacers can possess exceptional smooth surface morphology; The thickness of the spacer can be controlled with nanometer accuracy; And depending on fabrication conditions, the spacer layer is stimuli responsive and its thickness can be dynamically tuned. This thesis contains three interlinked components. First, we vary LbL spacer layer thickness and explore the change in fluorescence lifetime induced by the modified photonic density of states (PDOS), i.e., Purcell effects. Our experimental results agree well with theoretical predictions based on a classical dipole model, which also yields consistent values for the fluorophores' intrinsic fluorescence lifetime and quantum yield near a dielectric as well as a plasmonic interface. Based on this observation, we further demonstrate that self-assembled fluorophores can be used to probe the modified PDOS near optical micro- and nano-structures. These results naturally lead to the second component of our research. In particularly, based on the PDOS-induced changes in fluorescent lifetime, we develop a non-contact method that can measure morphological changes with nanoscale resolution. Our method relies on quantitatively linking fluorophore position with PDOS, and is validated through direct comparison with ellipsometry and atomic force microscopy (AFM) measurements. To demonstrate the potential application of this method, we investigated the swelling/deswelling of LbL films induced by pH changes. Our results indicate significant difference between a LbL film composed of a single polymer monolayer and a LbL film with 3 monolayers. Such stimuli-responsive polymers can be used to construct active and tunable plasmonic nano

  15. Particle nucleation in the tropical boundary layer and its coupling to marine sulfur sources

    PubMed

    Clarke; Davis; Kapustin; Eisele; Chen; Paluch; Lenschow; Bandy; Thornton; Moore; Mauldin; Tanner; Litchy; Carroll; Collins; Albercook

    1998-10-02

    New particle formation in a tropical marine boundary layer setting was characterized during NASA's Pacific Exploratory Mission-Tropics A program. It represents the clearest demonstration to date of aerosol nucleation and growth being linked to the natural marine sulfur cycle. This conclusion was based on real-time observations of dimethylsulfide, sulfur dioxide, sulfuric acid (gas), hydroxide, ozone, temperature, relative humidity, aerosol size and number distribution, and total aerosol surface area. Classic binary nucleation theory predicts no nucleation under the observed marine boundary layer conditions.

  16. Self-aligned process for forming microlenses at the tips of vertical silicon nanowires by atomic layer deposition

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dan, Yaping, E-mail: yaping.dan@sjtu.edu.cn; Chen, Kaixiang; Crozier, Kenneth B.

    The microlens is a key enabling technology in optoelectronics, permitting light to be efficiently coupled to and from devices such as image sensors and light-emitting diodes. Their ubiquitous nature motivates the development of new fabrication techniques, since existing methods face challenges as microlenses are scaled to smaller dimensions. Here, the authors demonstrate the formation of microlenses at the tips of vertically oriented silicon nanowires via a rapid atomic layer deposition process. The nature of the process is such that the microlenses are centered on the nanowires, and there is a self-limiting effect on the final sizes of the microlenses arisingmore » from the nanowire spacing. Finite difference time domain electromagnetic simulations are performed of microlens focusing properties, including showing their ability to enhance visible-wavelength absorption in silicon nanowires.« less

  17. Use of topical dorzolamide for patients with X-linked juvenile retinoschisis: case report.

    PubMed

    Bastos, André Luís Carvalho de Moura; Freitas, Bruno de Paula; Villas Boas, Oscar; Ramiro, Alexandre Campelo

    2008-01-01

    X-linked juvenile retinoschisis (XLRS) is a recessively inherited vitreoretinal degeneration characterized by macular pathology and splitting of the neuroretinal layers that is associated with alterations in the XLRS1 gene. There have been no therapeutic interventions known to be effective for patients with X-linked juvenile retinoschisis, but some studies are trying to determine the importance of dorzolamide for the treatment of foveal lesions in this disease. The authors, using optical coherence tomography, describe findings in a patient with X-linked juvenile retinoschisis, before and after a topical use of dorzolamide. Besides the improvement in his visual acuity, further studies are required to elucidate the real prevalence of nonresponse to dorzolamide and the frequency with which there may be a recurrence of foveal cystic changes during continued treatment.

  18. Layer-based buffer aware rate adaptation design for SHVC video streaming

    NASA Astrophysics Data System (ADS)

    Gudumasu, Srinivas; Hamza, Ahmed; Asbun, Eduardo; He, Yong; Ye, Yan

    2016-09-01

    This paper proposes a layer based buffer aware rate adaptation design which is able to avoid abrupt video quality fluctuation, reduce re-buffering latency and improve bandwidth utilization when compared to a conventional simulcast based adaptive streaming system. The proposed adaptation design schedules DASH segment requests based on the estimated bandwidth, dependencies among video layers and layer buffer fullness. Scalable HEVC video coding is the latest state-of-art video coding technique that can alleviate various issues caused by simulcast based adaptive video streaming. With scalable coded video streams, the video is encoded once into a number of layers representing different qualities and/or resolutions: a base layer (BL) and one or more enhancement layers (EL), each incrementally enhancing the quality of the lower layers. Such layer based coding structure allows fine granularity rate adaptation for the video streaming applications. Two video streaming use cases are presented in this paper. The first use case is to stream HD SHVC video over a wireless network where available bandwidth varies, and the performance comparison between proposed layer-based streaming approach and conventional simulcast streaming approach is provided. The second use case is to stream 4K/UHD SHVC video over a hybrid access network that consists of a 5G millimeter wave high-speed wireless link and a conventional wired or WiFi network. The simulation results verify that the proposed layer based rate adaptation approach is able to utilize the bandwidth more efficiently. As a result, a more consistent viewing experience with higher quality video content and minimal video quality fluctuations can be presented to the user.

  19. Evolving Pedagogical Perceptions of Teachers Integrating Ubiquitous Computing in Their Classrooms: A Case Study of the South Dakota Laptop Program

    ERIC Educational Resources Information Center

    Pogany, Wade S.

    2009-01-01

    With technology changing the world at a rapid rate, the impact of ubiquitous computing in the classroom has had an influence on education. As the number of one-to-one laptop initiatives grows, the need for further research on the effects of teaching and learning also increases. This case study sought to examine changes in teaching that resulted…

  20. Learning Potentials of the Ubiquitous Internet: Using Mobile Devices to Support the Individual, Social and Physical Context of the Learner

    ERIC Educational Resources Information Center

    Dalsgaard, Christian; Pedersen, Nicholai Friis; Aaen, Janus Holst

    2013-01-01

    The aim of this paper is to identify the key learning potentials of the ubiquitous internet. Rather than focusing on mobile technology or the mobility of the learner, the paper emphasises the ubiquity of internet access as a paramount catalyst for new learning in the digital age. From a sociocultural perspective the paper discusses different ways…

  1. A link prediction method for heterogeneous networks based on BP neural network

    NASA Astrophysics Data System (ADS)

    Li, Ji-chao; Zhao, Dan-ling; Ge, Bing-Feng; Yang, Ke-Wei; Chen, Ying-Wu

    2018-04-01

    Most real-world systems, composed of different types of objects connected via many interconnections, can be abstracted as various complex heterogeneous networks. Link prediction for heterogeneous networks is of great significance for mining missing links and reconfiguring networks according to observed information, with considerable applications in, for example, friend and location recommendations and disease-gene candidate detection. In this paper, we put forward a novel integrated framework, called MPBP (Meta-Path feature-based BP neural network model), to predict multiple types of links for heterogeneous networks. More specifically, the concept of meta-path is introduced, followed by the extraction of meta-path features for heterogeneous networks. Next, based on the extracted meta-path features, a supervised link prediction model is built with a three-layer BP neural network. Then, the solution algorithm of the proposed link prediction model is put forward to obtain predicted results by iteratively training the network. Last, numerical experiments on the dataset of examples of a gene-disease network and a combat network are conducted to verify the effectiveness and feasibility of the proposed MPBP. It shows that the MPBP with very good performance is superior to the baseline methods.

  2. Case study of inclined sporadic E layers in the Earth's ionosphere observed by CHAMP/GPS radio occultations: Coupling between the tilted plasma layers and internal waves

    NASA Astrophysics Data System (ADS)

    Gubenko, Vladimir N.; Pavelyev, A. G.; Kirillovich, I. A.; Liou, Y.-A.

    2018-04-01

    We have used the radio occultation (RO) satellite data CHAMP/GPS (Challenging Minisatellite Payload/Global Positioning System) for studying the ionosphere of the Earth. A method for deriving the parameters of ionospheric structures is based upon an analysis of the RO signal variations in the phase path and intensity. This method allows one to estimate the spatial displacement of a plasma layer with respect to the ray perigee, and to determine the layer inclination and height correction values. In this paper, we focus on the case study of inclined sporadic E (Es) layers in the high-latitude ionosphere based on available CHAMP RO data. Assuming that the internal gravity waves (IGWs) with the phase-fronts parallel to the ionization layer surfaces are responsible for the tilt angles of sporadic plasma layers, we have developed a new technique for determining the parameters of IGWs linked with the inclined Es structures. A small-scale internal wave may be modulating initially horizontal Es layer in height and causing a direction of the plasma density gradient to be rotated and aligned with that of the wave propagation vector k. The results of determination of the intrinsic wave frequency and period, vertical and horizontal wavelengths, intrinsic vertical and horizontal phase speeds, and other characteristics of IGWs under study are presented and discussed.

  3. A magnetospheric signature of some F layer positive storms

    NASA Technical Reports Server (NTRS)

    Miller, N. J.; Mayr, H. G.; Grebowsky, J. M.; Harris, I.; Tulunay, Y. K.

    1981-01-01

    Calculations of electron density distributions in the global thermosphere-ionosphere system perturbed by high-latitude thermospheric heating are presented which indicate a link between the heating and magnetospheric plasma disturbances near the equator. The calculations were made using a self-consistent model of the global sunlit thermosphere-ionosphere system describing the evolution of equatorial plasma disturbances. The heat input is found to cause electron density enhancements that propagate along magnetic field lines from the F2 maximum over mid-latitudes to the equator in the magnetosphere and which correspond to the positive phase of an F layer storm. The positive phase is shown to be generated by the induction of equatorward winds that raise the mid-latitude F layer through momentum transfer from neutral atoms to ionospheric ions, which ions pull electrons with them. Model results are used to identify plasma signatures of equatorward winds and an intensified magnetospheric electric field in Explorer 45 and Arial 4 measurements taken during the positive phase of an F layer storm.

  4. Energy harvesting from vibration with cross-linked polypropylene piezoelectrets

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Xiaoqing; Institute for Telecommunications Technology, Merckstrasse 25, 64283 Darmstadt; Wu, Liming

    Piezoelectret films are prepared by modification of the microstructure of polypropylene foam sheets cross-linked by electronic irradiation (IXPP), followed by proper corona charging. Young’s modulus, relative permittivity, and electromechanical coupling coefficient of the fabricated films, determined by dielectric resonance spectra, are about 0.7 MPa, 1.6, and 0.08, respectively. Dynamic piezoelectric d{sub 33} coefficients up to 650 pC/N at 200 Hz are achieved. The figure of merit (FOM, d{sub 33} ⋅ g{sub 33}) for a more typical d{sub 33} value of 400 pC/N is about 11.2 GPa{sup −1}. Vibration-based energy harvesting with one-layer and two-layer stacks of these films is investigatedmore » at various frequencies and load resistances. At an optimum load resistance of 9 MΩ and a resonance frequency of 800 Hz, a maximum output power of 120 μW, referred to the acceleration g due to gravity, is obtained for an energy harvester consisting of a one-layer IXPP film with an area of 3.14 cm{sup 2} and a seismic mass of 33.7 g. The output power can be further improved by using two-layer stacks of IXPP films in electric series. IXPP energy harvesters could be used to energize low-power electronic devices, such as wireless sensors and LED lights.« less

  5. Design and FPGA implementation for MAC layer of Ethernet PON

    NASA Astrophysics Data System (ADS)

    Zhu, Zengxi; Lin, Rujian; Chen, Jian; Ye, Jiajun; Chen, Xinqiao

    2004-04-01

    Ethernet passive optical network (EPON), which represents the convergence of low-cost, high-bandwidth and supporting multiple services, appears to be one of the best candidates for the next-generation access network. The work of standardizing EPON as a solution for access network is still underway in the IEEE802.3ah Ethernet in the first mile (EFM) task force. The final release is expected in 2004. Up to now, there has been no standard application specific integrated circuit (ASIC) chip available which fulfills the functions of media access control (MAC) layer of EPON. The MAC layer in EPON system has many functions, such as point-to-point emulation (P2PE), Ethernet MAC functionality, multi-point control protocol (MPCP), network operation, administration and maintenance (OAM) and link security. To implement those functions mentioned above, an embedded real-time operating system (RTOS) and a flexible programmable logic device (PLD) with an embedded processor are used. The software and hardware functions in MAC layer are realized through programming embedded microprocessor and field programmable gate array(FPGA). Finally, some experimental results are given in this paper. The method stated here can provide a valuable reference for developing EPON MAC layer ASIC.

  6. Human Intestinal Fluid Layer Separation: The Effect On Colloidal Structures & Solubility Of Lipophilic Compounds.

    PubMed

    Danny, Riethorst; Amitava, Mitra; Filippos, Kesisoglou; Wei, Xu; Jan, Tack; Joachim, Brouwers; Patrick, Augustijns

    2018-05-23

    In addition to individual intestinal fluid components, colloidal structures are responsible for enhancing the solubility of lipophilic compounds. The present study investigated the link between as well as the variability in the ultrastructure of fed state human intestinal fluids (FeHIF) and their solubilizing capacity for lipophilic compounds. For this purpose, FeHIF samples from 10 healthy volunteers with known composition and ultrastructure were used to determine the solubility of four lipophilic compounds. In light of the focus on solubility and ultrastructure, the study carefully considered the methodology of solubility determination in relation to colloid composition and solubilizing capacity of FeHIF. To determine the solubilizing capacity of human and simulated intestinal fluids, the samples were saturated with the compound of interest, shaken for 24 h, and centrifuged. When using FeHIF, solubilities were determined in the micellar layer of FeHIF, i.e. after removing the upper (lipid) layer (standard procedure), as well as in 'full' FeHIF (without removal of the upper layer). Compound concentrations were determined using HPLC-UV/fluorescence. To link the solubilizing capacity with the ultrastructure, all human and simulated fluids were imaged using transmission electron microscopy (TEM) before and after centrifugation and top layer (lipid) removal. Comparing the ultrastructure and solubilizing capacity of individual FeHIF samples demonstrated a high intersubject variability in postprandial intestinal conditions. Imaging of FeHIF after removal of the upper layer clearly showed that only micellar structures remain in the lower layer. This observation suggests that larger colloids such as vesicles and lipid droplets are contained in the upper, lipid layer. The solubilizing capacity of most FeHIF samples substantially increased with inclusion of this lipid layer. The relative increase in solubilizing capacity upon inclusion of the lipid layer was most pronounced

  7. Growing multiplex networks with arbitrary number of layers

    NASA Astrophysics Data System (ADS)

    Momeni, Naghmeh; Fotouhi, Babak

    2015-12-01

    This paper focuses on the problem of growing multiplex networks. Currently, the results on the joint degree distribution of growing multiplex networks present in the literature pertain to the case of two layers and are confined to the special case of homogeneous growth and are limited to the state state (that is, the limit of infinite size). In the present paper, we first obtain closed-form solutions for the joint degree distribution of heterogeneously growing multiplex networks with arbitrary number of layers in the steady state. Heterogeneous growth means that each incoming node establishes different numbers of links in different layers. We consider both uniform and preferential growth. We then extend the analysis of the uniform growth mechanism to arbitrary times. We obtain a closed-form solution for the time-dependent joint degree distribution of a growing multiplex network with arbitrary initial conditions. Throughout, theoretical findings are corroborated with Monte Carlo simulations. The results shed light on the effects of the initial network on the transient dynamics of growing multiplex networks and takes a step towards characterizing the temporal variations of the connectivity of growing multiplex networks, as well as predicting their future structural properties.

  8. Macular Choroidal Small-Vessel Layer, Sattler's Layer and Haller's Layer Thicknesses: The Beijing Eye Study.

    PubMed

    Zhao, Jing; Wang, Ya Xing; Zhang, Qi; Wei, Wen Bin; Xu, Liang; Jonas, Jost B

    2018-03-13

    To study macular choroidal layer thickness, 3187 study participants from the population-based Beijing Eye Study underwent spectral-domain optical coherence tomography with enhanced depth imaging for thickness measurements of the macular small-vessel layer, including the choriocapillaris, medium-sized choroidal vessel layer (Sattler's layer) and large choroidal vessel layer (Haller's layer). In multivariate analysis, greater thickness of all three choroidal layers was associated (all P < 0.05) with higher prevalence of age-related macular degeneration (AMD) (except for geographic atrophy), while it was not significantly (all P > 0.05) associated with the prevalence of open-angle glaucoma or diabetic retinopathy. There was a tendency (0.07 > P > 0.02) toward thinner choroidal layers in chronic angle-closure glaucoma. The ratio of small-vessel layer thickness to total choroidal thickness increased (P < 0.001; multivariate analysis) with older age and longer axial length, while the ratios of Sattler's layer and Haller's layer thickness to total choroidal thickness decreased. A higher ratio of small-vessel layer thickness to total choroidal thickness was significantly associated with a lower prevalence of AMD (early type, intermediate type, late geographic type). Axial elongation-associated and aging-associated choroidal thinning affected Haller's and Sattler's layers more markedly than the small-vessel layer. Non-exudative and exudative AMD, except for geographic atrophy, was associated with slightly increased choroidal thickness.

  9. Assessment of soil attributes and crop productivity after diversification of the ubiquitous corn-soybean rotation in the northwestern U.S. Corn Belt

    USDA-ARS?s Scientific Manuscript database

    Highly specialized cash-grain production systems based upon corn-soybean rotations under tilled soil management are common in the northwestern U.S. Corn Belt. This study, initiated in 1997, was conducted to determine if diversification of this ubiquitous corn-soybean rotation would affect soil char...

  10. DMP: Detouring Using Multiple Paths against Jamming Attack for Ubiquitous Networking System

    PubMed Central

    Kim, Mihui; Chae, Kijoon

    2010-01-01

    To successfully realize the ubiquitous network environment including home automation or industrial control systems, it is important to be able to resist a jamming attack. This has recently been considered as an extremely threatening attack because it can collapse the entire network, despite the existence of basic security protocols such as encryption and authentication. In this paper, we present a method of jamming attack tolerant routing using multiple paths based on zones. The proposed scheme divides the network into zones, and manages the candidate forward nodes of neighbor zones. After detecting an attack, detour nodes decide zones for rerouting, and detour packets destined for victim nodes through forward nodes in the decided zones. Simulation results show that our scheme increases the PDR (Packet Delivery Ratio) and decreases the delay significantly in comparison with rerouting by a general routing protocol on sensor networks, AODV (Ad hoc On Demand Distance Vector), and a conventional JAM (Jammed Area Mapping) service with one reroute. PMID:22319316

  11. Single-electron random-number generator (RNG) for highly secure ubiquitous computing applications

    NASA Astrophysics Data System (ADS)

    Uchida, Ken; Tanamoto, Tetsufumi; Fujita, Shinobu

    2007-11-01

    Since the security of all modern cryptographic techniques relies on unpredictable and irreproducible digital keys generated by random-number generators (RNGs), the realization of high-quality RNG is essential for secure communications. In this report, a new RNG, which utilizes single-electron phenomena, is proposed. A room-temperature operating silicon single-electron transistor (SET) having nearby an electron pocket is used as a high-quality, ultra-small RNG. In the proposed RNG, stochastic single-electron capture/emission processes to/from the electron pocket are detected with high sensitivity by the SET, and result in giant random telegraphic signals (GRTS) on the SET current. It is experimentally demonstrated that the single-electron RNG generates extremely high-quality random digital sequences at room temperature, in spite of its simple configuration. Because of its small-size and low-power properties, the single-electron RNG is promising as a key nanoelectronic device for future ubiquitous computing systems with highly secure mobile communication capabilities.

  12. DMP: detouring using multiple paths against jamming attack for ubiquitous networking system.

    PubMed

    Kim, Mihui; Chae, Kijoon

    2010-01-01

    To successfully realize the ubiquitous network environment including home automation or industrial control systems, it is important to be able to resist a jamming attack. This has recently been considered as an extremely threatening attack because it can collapse the entire network, despite the existence of basic security protocols such as encryption and authentication. In this paper, we present a method of jamming attack tolerant routing using multiple paths based on zones. The proposed scheme divides the network into zones, and manages the candidate forward nodes of neighbor zones. After detecting an attack, detour nodes decide zones for rerouting, and detour packets destined for victim nodes through forward nodes in the decided zones. Simulation results show that our scheme increases the PDR (Packet Delivery Ratio) and decreases the delay significantly in comparison with rerouting by a general routing protocol on sensor networks, AODV (Ad hoc On Demand Distance Vector), and a conventional JAM (Jammed Area Mapping) service with one reroute.

  13. Molecular layer deposition of polyurethane-Polymerisation at the very contact to native aluminium and copper

    NASA Astrophysics Data System (ADS)

    Fug, Frank; Petry, Adrien; Jost, Hendrik; Ahmed, Aisha; Zamanzade, Mohammad; Possart, Wulff

    2017-12-01

    Thin layers of polyurethane monomers (diol, triol, diisocyanate) are deposited from gas phase onto native aluminium and copper surfaces. According to infrared external reflection absorption spectra both alcohols undergo only weak physical interactions with both metals. The diisocyanate on the other hand reveals resistance against desorption and rich new spectral features indicate strong adhesion. Preparation of urethane layers by sequential deposition of diisocyanate and diol yields urethane linkages. Urethane is formed faster on Cu than on Al. Scanning force microscopy reveals heterogeneous layers with metal dependent morphology. They show poor resistance against tetrahydrofuran rinsing i.e. most part of the formed urethane containing molecules are removed. Nevertheless, a residue of molecules sticks on the metal. It contains strongly adsorbed isocyanates and few isocyanate units which are bonded to diol units via urethane links. Further improvement of the molecular layer deposition is necessary to achieve well-crosslinked polyurethane layers.

  14. Diel variation in the vertical distribution of deep-water scattering layers in the Gulf of Mexico

    NASA Astrophysics Data System (ADS)

    D'Elia, Marta; Warren, Joseph D.; Rodriguez-Pinto, Ivan; Sutton, Tracey T.; Cook, April; Boswell, Kevin M.

    2016-09-01

    Sound scattering layers (SSLs) are important components of oceanic ecosystems with ubiquitous distribution throughout the world's oceans. This vertical movement is an important mechanism for exchanging organic matter from the surface to the deep ocean, as many of the organisms comprising SSLs serve as prey resources for linking the lower trophic levels to larger predators. Variations in abundance and taxonomic composition of mesopelagic organisms were quantified using repeated discrete net sampling and acoustics over a 30-h survey, performed during 26-27 June 2011 at single site (27°28'51;N and 88°27'54;W) in the northern Gulf of Mexico. We acoustically classified the mesopelagic SSL into four broad taxonomic categories, crustacean and small non-swimbladdered fish (CSNSBF), large non-swimbladdered fish (LNSBF), swimbladdered fish (SBF) and unclassified and we quantified the abundance of mesopelagic organisms over three discrete depth intervals; epipelagic (0-200 m); upper mesopelagic (200-600 m) and lower mesopelagic (600-1000 m). Irrespective of the acoustic categories at dusk part of the acoustic energy redistributed from the mesopelagic into the upper epipelagic (shallower than 100 m) remaining however below the thermocline depth. At night higher variability in species composition was observed between 100 and 200 m suggested that a redistribution of organisms may also occur within the upper portion of the water column. Along the upper mesopelagic backscatter spectra from CSNSBF migrated between 400 and 460 m while spectra from the other categories moved to shallower depths (300 and 350 m), resulting in habitat separation from CSNSBF. Relatively small vertical changes in both acoustic backscatter and center of mass metrics of the deep mesopelagic were observed for CNSBF and LNSBF suggesting that these animals may be tightly connected to deeper (below 1000 m) mesopelagic habitats, and do not routinely migrate into the epipelagic.

  15. A transgenic rat with ubiquitous expression of firefly luciferase gene

    NASA Astrophysics Data System (ADS)

    Hakamata, Yoji; Murakami, Takashi; Kobayashi, Eiji

    2006-02-01

    In vivo imaging strategies provide cellular and molecular events in real time that helps us to understand biological processes in living animals. The development of molecular tags such as green fluorescent proteins and luciferase from the firefly Photinus pyralis has lead to a revolution in the visualization of complex biochemical processes. We developed a novel inbred transgenic rat strain containing firefly luciferase based on the transgenic (Tg) technique in rats. This Tg rat expressed the luciferase gene ubiquitously under control of the ROSA26 promoter. Cellular immune responsiveness against the luciferase protein was evaluated using conventional skin grafting and resulted in the long-term acceptance of Tg rat skin on wild-type rats. Strikingly, organ transplant with heart and small bowel demonstrated organ viability and graft survival, suggesting that cells from luciferase-Tg are transplantable to track their fate. Taking advantage of the less immunogenic luciferase, we also tested the role of hepatocyte-infusion in a liver injury model, and bone marrow-derived cells in a skin defect model. Employed in conjunction with modern advances in optical imaging, this luciferase-Tg rat system provides an innovative animal tool and a new means of facilitating biomedical research such as in the case of regeneration medicine.

  16. The ubiquitous reflex and its critics in post-revolutionary Russia.

    PubMed

    Sirotkina, Irina

    2009-03-01

    In the last century, the reflex was more than a scientific concept: it was a cultural idiom that could be used to various aims--political, scholarly, and artistic. In Russia in the 1920s, the reflex became a ubiquitous notion and a current word, part of the revolutionary discourse and, finally, a password to modernity. Two major factors contributed to it: physiological theories of the reflex, widespread in Russia at the early twentieth-century, and the materialist philosophy backed after the Revolution by the Communist party. Everybody who wished to be modern and materialist, in conformity with the official communist views, had to refer to reflexes. Yet, even in this period, the concept was not unproblematic and was criticized by some scientists, philosophers, artists and even Party members. In the paper, I describe both the array of uses of the term and the criticism it received in political, scientific and artistic discourses. It is not uncommon that, taking their origins in culture and common language, scientific concepts later return there in the form of metaphors. Similarly, the reflex was made into a rigorous scientific concept in the nineteenth century but, in the next century, it circulated as a cultural idiom penetrating various areas of political, artistic and academic life.

  17. The Use of Ubiquitous Sensor Technology in Evaluating Student Thought Process during Practical Operations for Improving Student Technical and Creative Skills

    ERIC Educational Resources Information Center

    Jou, Min; Wang, Jingying

    2015-01-01

    This study investigated a Ubiquitous Sensor System (USS) that we developed to assess student thought process during practical lessons on a real-time basis and to provide students with a reflective learning environment. Behavioral curves and data obtained by the USS would help students understand where they had made mistakes during practical…

  18. Formation mechanism of the graphite-rich protective layer in blast furnace hearths

    NASA Astrophysics Data System (ADS)

    Jiao, Ke-xin; Zhang, Jian-liang; Liu, Zheng-jian; Liu, Feng; Liang, Li-sheng

    2016-01-01

    A long campaign life of blast furnaces is heavily linked to the existence of a protective layer in their hearths. In this work, we conducted dissection studies and investigated damage in blast furnace hearths to estimate the formation mechanism of the protective layer. The results illustrate that a significant amount of graphite phase was trapped within the hearth protective layer. Furthermore, on the basis of the thermodynamic and kinetic calculations of the graphite precipitation process, a precipitation potential index related to the formation of the graphite-rich protective layer was proposed to characterize the formation ability of this layer. We determined that, under normal operating conditions, the precipitation of graphite phase from hot metal was thermodynamically possible. Among elements that exist in hot metal, C, Si, and P favor graphite precipitation, whereas Mn and Cr inhibit this process. Moreover, at the same hot-face temperature, an increase of carbon concentration in hot metal can shorten the precipitation time. Finally, the results suggest that measures such as reducing the hot-face temperature and increasing the degree of carbon saturation in hot metal are critically important to improve the precipitation potential index.

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

    PubMed Central

    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

  20. Poly(4-vinylphenol) gate insulator with cross-linking using a rapid low-power microwave induction heating scheme for organic thin-film-transistors

    NASA Astrophysics Data System (ADS)

    Fan, Ching-Lin; Shang, Ming-Chi; Hsia, Mao-Yuan; Wang, Shea-Jue; Huang, Bohr-Ran; Lee, Win-Der

    2016-03-01

    A Microwave-Induction Heating (MIH) scheme is proposed for the poly(4-vinylphenol) (PVP) gate insulator cross-linking process to replace the traditional oven heating cross-linking process. The cross-linking time is significantly decreased from 1 h to 5 min by heating the metal below the PVP layer using microwave irradiation. The necessary microwave power was substantially reduced to about 50 W by decreasing the chamber pressure. The MIH scheme is a good candidate to replace traditional thermal heating for cross-linking of PVP as the gate insulator for organic thin-film-transistors.

  1. Linking rainfall-induced landslides with debris flows runout patterns towards catchment scale hazard assessment

    NASA Astrophysics Data System (ADS)

    Fan, Linfeng; Lehmann, Peter; McArdell, Brian; Or, Dani

    2017-03-01

    Debris flows and landslides induced by heavy rainfall represent an ubiquitous and destructive natural hazard in steep mountainous regions. For debris flows initiated by shallow landslides, the prediction of the resulting pathways and associated hazard is often hindered by uncertainty in determining initiation locations, volumes and mechanical state of the mobilized debris (and by model parameterization). We propose a framework for linking a simplified physically-based debris flow runout model with a novel Landslide Hydro-mechanical Triggering (LHT) model to obtain a coupled landslide-debris flow susceptibility and hazard assessment. We first compared the simplified debris flow model of Perla (1980) with a state-of-the art continuum-based model (RAMMS) and with an empirical model of Rickenmann (1999) at the catchment scale. The results indicate that predicted runout distances by the Perla model are in reasonable agreement with inventory measurements and with the other models. Predictions of localized shallow landslides by LHT model provides information on water content of released mass. To incorporate effects of water content and flow viscosity as provided by LHT on debris flow runout, we adapted the Perla model. The proposed integral link between landslide triggering susceptibility quantified by LHT and subsequent debris flow runout hazard calculation using the adapted Perla model provides a spatially and temporally resolved framework for real-time hazard assessment at the catchment scale or along critical infrastructure (roads, railroad lines).

  2. Outer layer effects in wind-farm boundary layers: Coriolis forces and boundary layer height

    NASA Astrophysics Data System (ADS)

    Allaerts, Dries; Meyers, Johan

    2015-11-01

    In LES studies of wind-farm boundary layers, scale separation between the inner and outer region of the atmospheric boundary layer (ABL) is frequently assumed, i.e., wind turbines are presumed to fall within the inner layer and are not affected by outer layer effects. However, modern wind turbine and wind farm design tends towards larger rotor diameters and farm sizes, which means that outer layer effects will become more important. In a prior study, it was already shown for fully-developed wind farms that the ABL height influences the power performance. In this study, we use the in-house LES code SP-Wind to investigate the importance of outer layer effects on wind-farm boundary layers. In a suite of LES cases, the ABL height is varied by imposing a capping inversion with varying inversion strengths. Results indicate the growth of an internal boundary layer (IBL), which is limited in cases with low inversion layers. We further find that flow deceleration combined with Coriolis effects causes a change in wind direction throughout the farm. This effect increases with decreasing boundary layer height, and can result in considerable turbine wake deflection near the end of the farm. The authors are supported by the ERC (ActiveWindFarms, grant no: 306471). Computations were performed on VSC infrastructiure (Flemish Supercomputer Center), funded by the Hercules Foundation and the Flemish Government-department EWI.

  3. Three-dimensional spectral domain optical coherence tomography in X linked foveal retinoschisis

    PubMed Central

    Saxena, Sandeep; Manisha; Meyer, Carsten H

    2013-01-01

    Spectral domain optical coherence tomography (SD-OCT) was performed in two cases of bilateral X linked foveal retinoschisis of different age groups. On fundus examination spoke wheel and honeycomb pattern of cysts were observed along with retinal nerve fibre layer (RNFL) defects. On SD-OCT, schisis was observed in the outer plexiform layer. External limiting membrane disruption was observed in the subfoveal area, along with disruption of outer nuclear layer (ONL) and inner–outer segment junction. Elevation of ONL due to tractional pull of central palisade was a novel observation. Retinoschisis extended beyond the optic disc up to the nasal region. Extracted RNFL tomogram presented an unprecedented visualisation of schisis along 360° of the optic disc. Tractional elevation in the foveal area and schisis involving nasal region, not observed upon clinical examination, was highlighted on SD-OCT. This investigative modality is an important adjunct in the assessment of foveal retinoschisis. PMID:23563673

  4. Optical Coherence Tomography (OCT) Device Independent Intraretinal Layer Segmentation

    PubMed Central

    Ehnes, Alexander; Wenner, Yaroslava; Friedburg, Christoph; Preising, Markus N.; Bowl, Wadim; Sekundo, Walter; zu Bexten, Erdmuthe Meyer; Stieger, Knut; Lorenz, Birgit

    2014-01-01

    Purpose To develop and test an algorithm to segment intraretinal layers irrespectively of the actual Optical Coherence Tomography (OCT) device used. Methods The developed algorithm is based on the graph theory optimization. The algorithm's performance was evaluated against that of three expert graders for unsigned boundary position difference and thickness measurement of a retinal layer group in 50 and 41 B-scans, respectively. Reproducibility of the algorithm was tested in 30 C-scans of 10 healthy subjects each with the Spectralis and the Stratus OCT. Comparability between different devices was evaluated in 84 C-scans (volume or radial scans) obtained from 21 healthy subjects, two scans per subject with the Spectralis OCT, and one scan per subject each with the Stratus OCT and the RTVue-100 OCT. Each C-scan was segmented and the mean thickness for each retinal layer in sections of the early treatment of diabetic retinopathy study (ETDRS) grid was measured. Results The algorithm was able to segment up to 11 intraretinal layers. Measurements with the algorithm were within the 95% confidence interval of a single grader and the difference was smaller than the interindividual difference between the expert graders themselves. The cross-device examination of ETDRS-grid related layer thicknesses highly agreed between the three OCT devices. The algorithm correctly segmented a C-scan of a patient with X-linked retinitis pigmentosa. Conclusions The segmentation software provides device-independent, reliable, and reproducible analysis of intraretinal layers, similar to what is obtained from expert graders. Translational Relevance Potential application of the software includes routine clinical practice and multicenter clinical trials. PMID:24820053

  5. Entropy generation in a parallel-plate active magnetic regenerator with insulator layers

    NASA Astrophysics Data System (ADS)

    Mugica Guerrero, Ibai; Poncet, Sébastien; Bouchard, Jonathan

    2017-02-01

    This paper proposes a feasible solution to diminish conduction losses in active magnetic regenerators. Higher performances of these machines are linked to a lower thermal conductivity of the Magneto-Caloric Material (MCM) in the streamwise direction. The concept presented here involves the insertion of insulator layers along the length of a parallel-plate magnetic regenerator in order to reduce the heat conduction within the MCM. This idea is investigated by means of a 1D numerical model. This model solves not only the energy equations for the fluid and solid domains but also the magnetic circuit that conforms the experimental setup of reference. In conclusion, the addition of insulator layers within the MCM increases the temperature span, cooling load, and coefficient of performance by a combination of lower heat conduction losses and an increment of the global Magneto-Caloric Effect. The generated entropy by solid conduction, fluid convection, and conduction and viscous losses are calculated to help understand the implications of introducing insulator layers in magnetic regenerators. Finally, the optimal number of insulator layers is studied.

  6. Primary structure and glycosylation of the S-layer protein of Haloferax volcanii.

    PubMed Central

    Sumper, M; Berg, E; Mengele, R; Strobel, I

    1990-01-01

    The outer surface of the archaebacterium Haloferax volcanii (formerly named Halobacterium volcanii) is covered with a hexagonally packed surface (S) layer. The gene coding for the S-layer protein was cloned and sequenced. The mature polypeptide is composed of 794 amino acids and is preceded by a typical signal sequence of 34 amino acid residues. A highly hydrophobic stretch of 20 amino acids at the C-terminal end probably serves as a transmembrane domain. Clusters of threonine residues are located adjacent to this membrane anchor. The S-layer protein is a glycoprotein containing both N- and O-glycosidic bonds. Glucosyl-(1----2)-galactose disaccharides are linked to threonine residues. The primary structure and the glycosylation pattern of the S-layer glycoproteins from Haloferax volcanii and from Halobacterium halobium were compared and found to exhibit distinct differences, despite the fact that three-dimensional reconstructions from electron micrographs revealed no structural differences at least to the 2.5-nm level attained so far (M. Kessel, I. Wildhaber, S. Cohe, and W. Baumeister, EMBO J. 7:1549-1554, 1988). Images PMID:2123862

  7. Primary structure and glycosylation of the S-layer protein of Haloferax volcanii.

    PubMed

    Sumper, M; Berg, E; Mengele, R; Strobel, I

    1990-12-01

    The outer surface of the archaebacterium Haloferax volcanii (formerly named Halobacterium volcanii) is covered with a hexagonally packed surface (S) layer. The gene coding for the S-layer protein was cloned and sequenced. The mature polypeptide is composed of 794 amino acids and is preceded by a typical signal sequence of 34 amino acid residues. A highly hydrophobic stretch of 20 amino acids at the C-terminal end probably serves as a transmembrane domain. Clusters of threonine residues are located adjacent to this membrane anchor. The S-layer protein is a glycoprotein containing both N- and O-glycosidic bonds. Glucosyl-(1----2)-galactose disaccharides are linked to threonine residues. The primary structure and the glycosylation pattern of the S-layer glycoproteins from Haloferax volcanii and from Halobacterium halobium were compared and found to exhibit distinct differences, despite the fact that three-dimensional reconstructions from electron micrographs revealed no structural differences at least to the 2.5-nm level attained so far (M. Kessel, I. Wildhaber, S. Cohe, and W. Baumeister, EMBO J. 7:1549-1554, 1988).

  8. Crohn's disease-associated adherent-invasive Escherichia coli adhesion is enhanced by exposure to the ubiquitous dietary polysaccharide maltodextrin.

    PubMed

    Nickerson, Kourtney P; McDonald, Christine

    2012-01-01

    Crohn's disease (CD) is associated with intestinal dysbiosis evidenced by an altered microbiome forming thick biofilms on the epithelium. Additionally, adherent-invasive E. coli (AIEC) strains are frequently isolated from ileal lesions of CD patients indicating a potential role for these strains in disease pathogenesis. The composition and characteristics of the host microbiome are influenced by environmental factors, particularly diet. Polysaccharides added to food as emulsifiers, stabilizers or bulking agents have been linked to bacteria-associated intestinal disorders. The escalating consumption of polysaccharides in Western diets parallels an increased incidence of CD during the latter 20(th) century. In this study, the effect of a polysaccharide panel on adhesiveness of the CD-associated AIEC strain LF82 was analyzed to determine if these food additives promote disease-associated bacterial phenotypes. Maltodextrin (MDX), a polysaccharide derived from starch hydrolysis, markedly enhanced LF82 specific biofilm formation. Biofilm formation of multiple other E. coli strains was also promoted by MDX. MDX-induced E. coli biofilm formation was independent of polysaccharide chain length indicating a requirement for MDX metabolism. MDX exposure induced type I pili expression, which was required for MDX-enhanced biofilm formation. MDX also increased bacterial adhesion to human intestinal epithelial cell monolayers in a mechanism dependent on type 1 pili and independent of the cellular receptor CEACAM6, suggesting a novel mechanism of epithelial cell adhesion. Analysis of mucosa-associated bacteria from individuals with and without CD showed increased prevalence of malX, a gene essential for MDX metabolism, uniquely in the ileum of CD patients. These findings demonstrate that the ubiquitous dietary component MDX enhances E. coli adhesion and suggests a mechanism by which Western diets rich in specific polysaccharides may promote dysbiosis of gut microbes and contribute

  9. Frequency Spectrum for New Aviation Data Links: Initial Study Results

    NASA Technical Reports Server (NTRS)

    Matolak, David W.; Branstetter, James R.

    2004-01-01

    We describe results from an initial study to assess the suitability of various spectral bands for supporting the deployment of new aviation data links (ADL). The study focused on systems and spectral bands that can deliver VHF data link (VDL)-or-higher data rates in a two-way communication setting, including air-ground, ground-air, and air-air modes of operation. In the first part of our paper, we briefly discuss the current situation regarding communications, navigation, and surveillance (CNS) links and existing spectrum, and the well-known need for new aviation data links. We next provide an overview of related systems, and discuss key factors involved in the use of spectrum in various bands for any future integrated CNS data link, addressing primarily the lower few layers of the communications protocol stack. Desired attributes of a new ADL system are discussed, and the beneficial aspects of a particular transmission technique spread spectrum are summarized. We also provide a short list of several example potential spectral regions, and note that while none of the existing systems will likely meet the full range of desired features of a new ADL, several systems and spectral regions offer promise in terms of one or more characteristics. A detailed discussion and evaluation of these spectral regions is proposed as future work. We include a few brief examples to illustrate initial technical results regarding spread spectrum overlay, also a subject for future work.

  10. RIDES: Robust Intrusion Detection System for IP-Based Ubiquitous Sensor Networks.

    PubMed

    Amin, Syed Obaid; Siddiqui, Muhammad Shoaib; Hong, Choong Seon; Lee, Sungwon

    2009-01-01

    The IP-based Ubiquitous Sensor Network (IP-USN) is an effort to build the "Internet of things". By utilizing IP for low power networks, we can benefit from existing well established tools and technologies of IP networks. Along with many other unresolved issues, securing IP-USN is of great concern for researchers so that future market satisfaction and demands can be met. Without proper security measures, both reactive and proactive, it is hard to envisage an IP-USN realm. In this paper we present a design of an IDS (Intrusion Detection System) called RIDES (Robust Intrusion DEtection System) for IP-USN. RIDES is a hybrid intrusion detection system, which incorporates both Signature and Anomaly based intrusion detection components. For signature based intrusion detection this paper only discusses the implementation of distributed pattern matching algorithm with the help of signature-code, a dynamically created attack-signature identifier. Other aspects, such as creation of rules are not discussed. On the other hand, for anomaly based detection we propose a scoring classifier based on the SPC (Statistical Process Control) technique called CUSUM charts. We also investigate the settings and their effects on the performance of related parameters for both of the components.

  11. Adaptability as the key to success for the ubiquitous marine nitrite oxidizer Nitrococcus

    PubMed Central

    Füssel, Jessika; Lücker, Sebastian; Yilmaz, Pelin; Nowka, Boris; van Kessel, Maartje A. H. J.; Bourceau, Patric; Hach, Philipp F.; Littmann, Sten; Berg, Jasmine; Spieck, Eva; Daims, Holger; Kuypers, Marcel M. M.; Lam, Phyllis

    2017-01-01

    Nitrite-oxidizing bacteria (NOB) have conventionally been regarded as a highly specialized functional group responsible for the production of nitrate in the environment. However, recent culture-based studies suggest that they have the capacity to lead alternative lifestyles, but direct environmental evidence for the contribution of marine nitrite oxidizers to other processes has been lacking to date. We report on the alternative biogeochemical functions, worldwide distribution, and sometimes high abundance of the marine NOB Nitrococcus. These largely overlooked bacteria are capable of not only oxidizing nitrite but also reducing nitrate and producing nitrous oxide, an ozone-depleting agent and greenhouse gas. Furthermore, Nitrococcus can aerobically oxidize sulfide, thereby also engaging in the sulfur cycle. In the currently fast-changing global oceans, these findings highlight the potential functional switches these ubiquitous bacteria can perform in various biogeochemical cycles, each with distinct or even contrasting consequences. PMID:29109973

  12. Linking macroscopic with microscopic neuroanatomy using synthetic neuronal populations.

    PubMed

    Schneider, Calvin J; Cuntz, Hermann; Soltesz, Ivan

    2014-10-01

    Dendritic morphology has been shown to have a dramatic impact on neuronal function. However, population features such as the inherent variability in dendritic morphology between cells belonging to the same neuronal type are often overlooked when studying computation in neural networks. While detailed models for morphology and electrophysiology exist for many types of single neurons, the role of detailed single cell morphology in the population has not been studied quantitatively or computationally. Here we use the structural context of the neural tissue in which dendritic trees exist to drive their generation in silico. We synthesize the entire population of dentate gyrus granule cells, the most numerous cell type in the hippocampus, by growing their dendritic trees within their characteristic dendritic fields bounded by the realistic structural context of (1) the granule cell layer that contains all somata and (2) the molecular layer that contains the dendritic forest. This process enables branching statistics to be linked to larger scale neuroanatomical features. We find large differences in dendritic total length and individual path length measures as a function of location in the dentate gyrus and of somatic depth in the granule cell layer. We also predict the number of unique granule cell dendrites invading a given volume in the molecular layer. This work enables the complete population-level study of morphological properties and provides a framework to develop complex and realistic neural network models.

  13. Linking Macroscopic with Microscopic Neuroanatomy Using Synthetic Neuronal Populations

    PubMed Central

    Schneider, Calvin J.; Cuntz, Hermann; Soltesz, Ivan

    2014-01-01

    Dendritic morphology has been shown to have a dramatic impact on neuronal function. However, population features such as the inherent variability in dendritic morphology between cells belonging to the same neuronal type are often overlooked when studying computation in neural networks. While detailed models for morphology and electrophysiology exist for many types of single neurons, the role of detailed single cell morphology in the population has not been studied quantitatively or computationally. Here we use the structural context of the neural tissue in which dendritic trees exist to drive their generation in silico. We synthesize the entire population of dentate gyrus granule cells, the most numerous cell type in the hippocampus, by growing their dendritic trees within their characteristic dendritic fields bounded by the realistic structural context of (1) the granule cell layer that contains all somata and (2) the molecular layer that contains the dendritic forest. This process enables branching statistics to be linked to larger scale neuroanatomical features. We find large differences in dendritic total length and individual path length measures as a function of location in the dentate gyrus and of somatic depth in the granule cell layer. We also predict the number of unique granule cell dendrites invading a given volume in the molecular layer. This work enables the complete population-level study of morphological properties and provides a framework to develop complex and realistic neural network models. PMID:25340814

  14. Observation of low-frequency acoustic surface waves in the nocturnal boundary layer.

    PubMed

    Talmadge, Carrick L; Waxler, Roger; Di, Xiao; Gilbert, Kenneth E; Kulichkov, Sergey

    2008-10-01

    A natural terrain surface, because of its porosity, can support an acoustic surface wave that is a mechanical analog of the familiar vertically polarized surface wave in AM radio transmission. At frequencies of several hundred hertz, the acoustic surface wave is attenuated over distances of a few hundred meters. At lower frequencies (e.g., below approximately 200 Hz) the attenuation is much less, allowing surface waves to propagate thousands of meters. At night, a low-frequency surface wave is generally present at long ranges even when downward refraction is weak. Thus, surface waves represent a ubiquitous nighttime transmission mode that exists even when other transmission modes are weak or absent. Data from recent nighttime field experiments and theoretical calculations are presented, demonstrating the persistence of the surface wave under different meteorological conditions. The low-frequency surface wave described here is the "quasiharmonical" tail observed previously in nighttime measurements but not identified by S. Kulichkov and his colleagues (Chunchuzov, I. P. et al. 1990. "On acoustical impulse propagation in a moving inhomogeneous atmospheric layer," J. Acoust. Soc. Am. 88, 455-461).

  15. Dry Rainbelts: Understanding Boundary Layer Controls on the ITCZ Using a Dry Dynamical Core

    NASA Astrophysics Data System (ADS)

    Hill, S. A.; Bordoni, S.; Mitchell, J.

    2017-12-01

    Though migrations of Earth's Intertropical Convergence Zone (ITCZ) are often interpreted in terms of meridional energy transports, a recent study using an idealized, aquaplanet GCM indicates that the ITCZ's position is also linked to the character of the boundary layer momentum budget. Namely, moist convection within the ITCZ roughly coincides with a transition in the role of relative vorticity advection in the boundary layer, from being of leading-order to lower-order importance. This is insensitive to the presence of mid-latitude eddies or thermal inertia and holds over a range of planetary rotation rates, with this transitional regime and the ITCZ extending farther poleward the slower the planet is rotating. We use an even simpler model, a dry dynamical core, to further refine the theoretical understanding of these results, via simulations analogous to and extending the aforementioned moist cases. The importance of planetary rotation and lack thereof for both baroclinic eddies and thermal inertia emerge in the dry simulations also, implying base causes rooted in simpler, steady-state, solsticial, axisymmetric, dry dynamics. We further elucidate the role of the boundary layer dynamical processes through comparison with arguments dating to at least 1972 (although largely overlooked in recent literature) that convection is forced by convergence driven by a shallowing of the boundary layer depth, with this shallowing resulting from the transition from an advective to an Ekman balance on frictional drag. We discuss the potential links between this dynamical perspective and the popular energetic framework for ITCZ migrations and the resulting implications for moist convection on Earth and other planetary bodies.

  16. Improved CLARAty Functional-Layer/Decision-Layer Interface

    NASA Technical Reports Server (NTRS)

    Estlin, Tara; Rabideau, Gregg; Gaines, Daniel; Johnston, Mark; Chouinard, Caroline; Nessnas, Issa; Shu, I-Hsiang

    2008-01-01

    Improved interface software for communication between the CLARAty Decision and Functional layers has been developed. [The Coupled Layer Architecture for Robotics Autonomy (CLARAty) was described in Coupled-Layer Robotics Architecture for Autonomy (NPO-21218), NASA Tech Briefs, Vol. 26, No. 12 (December 2002), page 48. To recapitulate: the CLARAty architecture was developed to improve the modularity of robotic software while tightening coupling between planning/execution and basic control subsystems. Whereas prior robotic software architectures typically contained three layers, the CLARAty contains two layers: a decision layer (DL) and a functional layer (FL).] Types of communication supported by the present software include sending commands from DL modules to FL modules and sending data updates from FL modules to DL modules. The present software supplants prior interface software that had little error-checking capability, supported data parameters in string form only, supported commanding at only one level of the FL, and supported only limited updates of the state of the robot. The present software offers strong error checking, and supports complex data structures and commanding at multiple levels of the FL, and relative to the prior software, offers a much wider spectrum of state-update capabilities.

  17. Effect of endosulfan on immunological competence of layer birds.

    PubMed

    Singh, P P; Kumar, Ashok; Chauhan, R S; Pankaj, P K

    2016-07-01

    The present study was aimed to investigate the immunological competence of endosulfan insecticide after limited oral administration in White Leghorn layer chickens. A total of 20 White Leghorn birds were given endosulfan in drinking water at 30 ppm/bird/day (no observable effect level dose) for a period of 3-months. Immune competence status of layer birds and chicks hatched from endosulfan offered birds were estimated at 15-day interval in layer birds and at monthly interval in chicks using immunological, biochemical parameters, and teratological estimates. There was a significant decrease in levels of total leukocytes count, absolute lymphocyte count, absolute heterophil count, total serum protein, serum albumin, serum globulin, and serum gamma globulin in the birds fed with endosulfan as compared to control. Similarly, immune competence tests such as lymphocyte stimulation test, oxidative burst assay, and enzyme-linked immunosorbent assay tests indicated lower immunity in birds treated with endosulfan as compared to control. Subsequently, chicks produced from endosulfan-treated birds were also examined for immune competence, but no significant difference was observed between chicks of both the groups. The exposure to endosulfan in limited oral dosage was able to exhibit hemo-biochemical and other changes that could be correlated with changes in the immunological profile of layer chickens suggesting cautious usage of endosulfan insecticide in poultry sheds.

  18. The role of interfacial water layer in atmospherically relevant charge separation

    NASA Astrophysics Data System (ADS)

    Bhattacharyya, Indrani

    Charge separation at interfaces is important in various atmospheric processes, such as thunderstorms, lightning, and sand storms. It also plays a key role in several industrial processes, including ink-jet printing and electrostatic separation. Surprisingly, little is known about the underlying physics of these charging phenomena. Since thin films of water are ubiquitous, they may play a role in these charge separation processes. This talk will focus on the experimental investigation of the role of a water adlayer in interfacial charging, with relevance to meteorologically important phenomena, such as atmospheric charging due to wave actions on oceans and sand storms. An ocean wave generates thousands of bubbles, which upon bursting produce numerous large jet droplets and small film droplets that are charged. In the 1960s, Blanchard showed that the jet droplets are positively charged. However, the charge on the film droplets was not known. We designed an experiment to exclusively measure the charge on film droplets generated by bubble bursting on pure water and aqueous salt solution surfaces. We measured their charge to be negative and proposed a model where a slight excess of hydroxide ions in the interfacial water layer is responsible for generating these negatively charged droplets. The findings from this research led to a better understanding of the ionic disposition at the air-water interface. Sand particles in a wind-blown sand layer, or 'saltation' layer, become charged due to collisions, so much so, that it can cause lightning. Silica, being hydrophilic, is coated with a water layer even under low-humidity conditions. To investigate the importance of this water adlayer in charging the silica surfaces, we performed experiments to measure the charge on silica surfaces due to contact and collision processes. In case of contact charging, the maximum charge separation occurred at an optimum relative humidity. On the contrary, in collisional charging process, no

  19. Bio-inspired layered chitosan/graphene oxide nanocomposite hydrogels with high strength and pH-driven shape memory effect.

    PubMed

    Zhang, Yaqian; Zhang, Min; Jiang, Haoyang; Shi, Jinli; Li, Feibo; Xia, Yanhong; Zhang, Gongzheng; Li, Huanjun

    2017-12-01

    The layered nanocomposite hydrogel films containing chitosan (CS) and graphene oxide (GO) have been prepared by water evaporation induced self-assembly and subsequent physical cross-linking in alkaline solution. The layered CS/GO hydrogel films obtained have a nacre-like brick-and-mortar microstructure, which contributes to their excellent mechanical properties. The tensile strength and elongation at break of the hydrogel films with 5wt% GO are 5.35MPa and 193.5%, respectively, which are comparable to natural costal cartilage. Furthermore, the CS/GO hydrogel films exhibited pH-driven shape memory effect, and this unique phenomenon is mainly attributed to the reversible transition of partial physically cross-linking corresponding to hydrogen bondings and hydrophobic interactions between CS polymer chains due to pH changing. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Low-temperature atomic layer epitaxy of AlN ultrathin films by layer-by-layer, in-situ atomic layer annealing.

    PubMed

    Shih, Huan-Yu; Lee, Wei-Hao; Kao, Wei-Chung; Chuang, Yung-Chuan; Lin, Ray-Ming; Lin, Hsin-Chih; Shiojiri, Makoto; Chen, Miin-Jang

    2017-01-03

    Low-temperature epitaxial growth of AlN ultrathin films was realized by atomic layer deposition (ALD) together with the layer-by-layer, in-situ atomic layer annealing (ALA), instead of a high growth temperature which is needed in conventional epitaxial growth techniques. By applying the ALA with the Ar plasma treatment in each ALD cycle, the AlN thin film was converted dramatically from the amorphous phase to a single-crystalline epitaxial layer, at a low deposition temperature of 300 °C. The energy transferred from plasma not only provides the crystallization energy but also enhances the migration of adatoms and the removal of ligands, which significantly improve the crystallinity of the epitaxial layer. The X-ray diffraction reveals that the full width at half-maximum of the AlN (0002) rocking curve is only 144 arcsec in the AlN ultrathin epilayer with a thickness of only a few tens of nm. The high-resolution transmission electron microscopy also indicates the high-quality single-crystal hexagonal phase of the AlN epitaxial layer on the sapphire substrate. The result opens a window for further extension of the ALD applications from amorphous thin films to the high-quality low-temperature atomic layer epitaxy, which can be exploited in a variety of fields and applications in the near future.

  1. Low-temperature atomic layer epitaxy of AlN ultrathin films by layer-by-layer, in-situ atomic layer annealing

    PubMed Central

    Shih, Huan-Yu; Lee, Wei-Hao; Kao, Wei-Chung; Chuang, Yung-Chuan; Lin, Ray-Ming; Lin, Hsin-Chih; Shiojiri, Makoto; Chen, Miin-Jang

    2017-01-01

    Low-temperature epitaxial growth of AlN ultrathin films was realized by atomic layer deposition (ALD) together with the layer-by-layer, in-situ atomic layer annealing (ALA), instead of a high growth temperature which is needed in conventional epitaxial growth techniques. By applying the ALA with the Ar plasma treatment in each ALD cycle, the AlN thin film was converted dramatically from the amorphous phase to a single-crystalline epitaxial layer, at a low deposition temperature of 300 °C. The energy transferred from plasma not only provides the crystallization energy but also enhances the migration of adatoms and the removal of ligands, which significantly improve the crystallinity of the epitaxial layer. The X-ray diffraction reveals that the full width at half-maximum of the AlN (0002) rocking curve is only 144 arcsec in the AlN ultrathin epilayer with a thickness of only a few tens of nm. The high-resolution transmission electron microscopy also indicates the high-quality single-crystal hexagonal phase of the AlN epitaxial layer on the sapphire substrate. The result opens a window for further extension of the ALD applications from amorphous thin films to the high-quality low-temperature atomic layer epitaxy, which can be exploited in a variety of fields and applications in the near future. PMID:28045075

  2. Ester-free cross-linker molecules for ultraviolet-light-cured polysilsesquioxane gate dielectric layers of organic thin-film transistors

    NASA Astrophysics Data System (ADS)

    Okada, Shuichi; Nakahara, Yoshio; Uno, Kazuyuki; Tanaka, Ichiro

    2018-04-01

    Pentacene thin-film transistors (TFTs) were fabricated with ultraviolet-light (UV)-cured polysilsesquioxane (PSQ) gate dielectric layers using cross-linker molecules with or without ester groups. To polymerize PSQ without ester groups, thiol-ene reaction was adopted. The TFTs fabricated with PSQ layers comprising ester-free cross-linkers showed a higher carrier mobility than the TFTs with PSQ layers cross-linked with ester groups, which had large electric dipole moments that limited the carrier mobility. It was demonstrated that the thiol-ene reaction is more suitable than the conventional radical reaction for UV-cured PSQ with small dielectric constant.

  3. The Network for the Detection of Stratospheric Change: Investigating the Ozone Layer and Its Links to Global Climate

    NASA Astrophysics Data System (ADS)

    Kurylo, M. J.

    2002-05-01

    documented the increase and leveling-off of ozone-depleting chemicals in the atmosphere and the continued growth of greenhouse gases. Because of its worldwide dimension, the NDSC has been recognized as a major component of the international upper atmosphere research program. As such, it has been endorsed by national and international scientific agencies, including the United Nations Environmental Programme (UNEP) and the International Ozone Commission (IOC) of the International Association of Meteorology and Atmospheric Physics (IAMAP). It has also been recognized by the World Meteorological Organization (WMO) as a major contributor to WMO's Global Ozone Observing System (GO3OS) within the frame of its Global Atmosphere Watch (GAW) Programme. While the NDSC remains committed to monitoring changes in the stratosphere, with an emphasis on the long-term evolution of the ozone layer (its decay, likely stabilization and expected recovery), it has recently broadened its interest and objectives to encompass new and emerging challenges including interactions between the stratosphere and the troposphere, as well as related links to global climate. Additional examples of NDCS measurement and analysis accomplishments as well as details about the NDSC-SC implementation, structure and operation, data archiving, and related protocols and publications can be found at the NDSC home page http://www.ndsc.ws.

  4. Trends in Connectivity Technologies and Their Socioeconomic Impacts. Final Report of the Study: Policy Options for the Ubiquitous Internet Society. Technical Report

    ERIC Educational Resources Information Center

    Cave, Jonathan; van Oranje-Nassau, Constantijn; Schindler, Helen Rebecca; Shehabi, Ala'a; Brutscher, Philipp-Bastian; Robinson, Neil

    2009-01-01

    This report is intended to inform the European Commission's DG Information Society and Media in developing its policies for the period 2010-2020. It is targeted to policymakers with expert knowledge of the field. The report summarises the work conducted in the study: "Policy Options for the Ubiquitous Internet Society". It builds on…

  5. High Static Stability in the Mixed Layer Above the Extratropical Tropopause

    NASA Astrophysics Data System (ADS)

    Kunz, A.; Konopka, P.; Müller, R.; Pan, L. L.; Schiller, C.

    2009-04-01

    A strong relationship between the static stability N2 in the tropopause inversion layer (TIL) and the intensity of mixing is evident from in-situ observations during SPURT. With a new simple measure of mixing intensity based on O3/CO tracer correlations, a very high mixing intensity connected to a high N2 is found in the extratropical mixing layer. Using radiative transfer calculations we simulate the influence of trace gases such as O3 and H2O on the temperature gradient and thus on the static stability above the tropopause in an idealized (L-shaped) non-mixed and reference mixed atmosphere. N2 enhances due to an intensifying mixing in the LS. At the same time the temperature decreases together with a development of an inversion and the TIL. Hereby H2O plays the dominant role in maintenance the temperature inversion and the TIL structure. In case of non mixed profiles the TIL vanishes. The results motivate a link between the mixing layer and the TIL. The mixing layer contains on the one hand older air masses, with high values of N2 due to radiative adjustment. This part of the mixing layer is spatial identically to the TIL. On the other hand, there are younger air masses with somehow lower N2 values within the mixing layer, because of fast intrusion processes from the troposphere due to the permeability or so-called mid-latitude-breaks associated with the jet.

  6. Designing Two-Dimensional Dirac Heterointerfaces of Few-Layer Graphene and Tetradymite-Type Sb2Te3 for Thermoelectric Applications.

    PubMed

    Jang, Woosun; Lee, Jiwoo; In, Chihun; Choi, Hyunyong; Soon, Aloysius

    2017-12-06

    Despite the ubiquitous nature of the Peltier effect in low-dimensional thermoelectric devices, the influence of finite temperature on the electronic structure and transport in the Dirac heterointerfaces of the few-layer graphene and layered tetradymite, Sb 2 Te 3 (which coincidently have excellent thermoelectric properties) are not well understood. In this work, using the first-principles density-functional theory calculations, we investigate the detailed atomic and electronic structure of these Dirac heterointerfaces of graphene and Sb 2 Te 3 and further re-examine the effect of finite temperature on the electronic band structures using a phenomenological temperature-broadening model based on Fermi-Dirac statistics. We then proceed to understand the underlying charge redistribution process in this Dirac heterointerfaces and through solving the Boltzmann transport equation, we present the theoretical evidence of electron-hole asymmetry in its electrical conductivity as a consequence of this charge redistribution mechanism. We finally propose that the hexagonal-stacked Dirac heterointerfaces are useful as efficient p-n junction building blocks in the next-generation thermoelectric devices where the electron-hole asymmetry promotes the thermoelectric transport by "hot" excited charge carriers.

  7. Ubiquitous Gammaproteobacteria dominate dark carbon fixation in coastal sediments.

    PubMed

    Dyksma, Stefan; Bischof, Kerstin; Fuchs, Bernhard M; Hoffmann, Katy; Meier, Dimitri; Meyerdierks, Anke; Pjevac, Petra; Probandt, David; Richter, Michael; Stepanauskas, Ramunas; Mußmann, Marc

    2016-08-01

    Marine sediments are the largest carbon sink on earth. Nearly half of dark carbon fixation in the oceans occurs in coastal sediments, but the microorganisms responsible are largely unknown. By integrating the 16S rRNA approach, single-cell genomics, metagenomics and transcriptomics with (14)C-carbon assimilation experiments, we show that uncultured Gammaproteobacteria account for 70-86% of dark carbon fixation in coastal sediments. First, we surveyed the bacterial 16S rRNA gene diversity of 13 tidal and sublittoral sediments across Europe and Australia to identify ubiquitous core groups of Gammaproteobacteria mainly affiliating with sulfur-oxidizing bacteria. These also accounted for a substantial fraction of the microbial community in anoxic, 490-cm-deep subsurface sediments. We then quantified dark carbon fixation by scintillography of specific microbial populations extracted and flow-sorted from sediments that were short-term incubated with (14)C-bicarbonate. We identified three distinct gammaproteobacterial clades covering diversity ranges on family to order level (the Acidiferrobacter, JTB255 and SSr clades) that made up >50% of dark carbon fixation in a tidal sediment. Consistent with these activity measurements, environmental transcripts of sulfur oxidation and carbon fixation genes mainly affiliated with those of sulfur-oxidizing Gammaproteobacteria. The co-localization of key genes of sulfur and hydrogen oxidation pathways and their expression in genomes of uncultured Gammaproteobacteria illustrates an unknown metabolic plasticity for sulfur oxidizers in marine sediments. Given their global distribution and high abundance, we propose that a stable assemblage of metabolically flexible Gammaproteobacteria drives important parts of marine carbon and sulfur cycles.

  8. Mic Flocks in the Cloud: Harnessing Mobile Ubiquitous Sensor Networks

    NASA Astrophysics Data System (ADS)

    Garces, M. A.; Christe, A.

    2015-12-01

    Smartphones provide a commercial, off-the-shelf solution to capture, store, analyze, and distribute infrasound using on-board or external microphones (mics) as well as on-board barometers. Free iOS infrasound apps can be readily downloaded from the Apple App Store, and Android versions are in progress. Infrasound propagates for great distances, has low sample rates, and provides a tractable pilot study scenario for open distributed sensor networks at regional and global scales using one of the most ubiquitous sensors on Earth - microphones. Data collection is no longer limited to selected vendors at exclusive prices: anybody on Earth can record and stream infrasound, and the diversity of recording systems and environments is rapidly expanding. Global deployment may be fast and easy (www.redvox.io), but comes with the cost of increasing data volume, velocity, variety, and complexity. Flocking - the collective motion of mobile agents - is a natural human response to threats or events of interest. Anticipating, modeling and harnessing flocking sensor topologies will be necessary for adaptive array and network processing. The increasing data quantity and complexity will exceed the processing capacity of human analysts and most research servers. We anticipate practical real-time applications will require the on-demand adaptive scalability and resources of the Cloud. Cloud architectures for such heterogeneous sensor networks will consider eventual integration into the Global Earth Observation System of Systems (GEOSS).

  9. Linking THEMIS Orbital Data to MSL GTS Measurements: The Thermophysical Properties of the Bagnold Dunes, Mars

    NASA Astrophysics Data System (ADS)

    Edwards, C. S.; Piqueux, S.; Hamilton, V. E.; Fergason, R. L.; Herkenhoff, K. E.; Vasavada, A. R.; Sacks, L. E.; Lewis, K. W.; Smith, M. D.

    2017-12-01

    The surface of Mars has been characterized using orbital thermal infrared observations from the time of the Mariner 9 and Viking missions. More recent observations from missions such as the Thermal Emission Spectrometer onboard the Mars Global Surveyor and the Thermal Emission Imaging System (THEMIS) instrument onboard the 2001 Mars Odyssey orbiter have continued to expand global coverage at progressively higher resolution. THEMIS has been producing 100 m/pixel thermal infrared data with nearly global coverage of the surface for >15 years and has enabled new investigations that successfully link outcrop-scale information to physical properties of the surface. However, significant discrepancies between morphologies and interpreted surface properties derived from orbital thermal measurements remain, requiring a robust link to direct surface measurements. Here, we compare the thermophysical properties and particle sizes derived from the Mars Science Laboratory (MSL) rover's Ground Temperature Sensor (GTS), to those derived orbitally from THEMIS, ultimately linking these measurements to ground truth particle sizes determined from Mars Hand Lens Imager (MAHLI) images. We focus on the relatively homogenous Bagnold dunes, specifically Namib dune, and in general find that all three datasets report consistent particle sizes for the Bagnold dunes ( 110-350 µm, and are within measurement and model uncertainties), indicating that particles sizes of homogeneous materials determined from thermal measurements are reliable. In addition, we assess several potentially significant effects that could influence the derived particle sizes, including: 1) fine-scale (cm-m scale) ripples, and 2) thin (mm-cm) layering of indurated/armored materials. To first order, we find that small scale ripples and thin layers do not significantly affect the determination of bulk thermal inertia determined from orbit. However, a layer of coarser/indurated material and/or fine-scale layering does change

  10. Computational solvation dynamics of oxyquinolinium betaine linked to trehalose.

    PubMed

    Heid, Esther; Schröder, Christian

    2016-10-28

    Studying the changed water dynamics in the hydration layers of biomolecules is an important step towards fuller understanding of their function and mechanisms, but has shown to be quite difficult. The measurement of the time-dependent Stokes shift of a chromophore attached to the biomolecule is a promising method to achieve this goal, as published in Sajadi et al. [J. Phys. Chem. Lett., 5, 1845 (2014).] where trehalose was used as biomolecule, 1-methyl-6-oxyquinolinium betaine as chromophore, and water as solvent. An overall retardation of solvent molecules is then obtained by comparison of the linked system to the same system without trehalose, but contributions from different subgroups of solvent molecules, for example, molecules close to or far from trehalose, are unknown. The difficulty arising from these unknown contributions of retarded and possibly unretarded solvent molecules is overcome in this work by conducting computer simulations on this system and decomposing the overall signal into the contributions from various molecules at different locations. We performed non-equilibrium molecular dynamics simulation using a polarizable water model and a non-polarizable solute model and could reproduce the experimental time-dependent Stokes shift accurately for the linked trehalose-oxyquinolinium and the pure oxyquinolinium over a wide temperature range, indicating the correctness of our employed models. Decomposition of the shift into contributions from different solvent subgroups showed that the amplitude of the measured shift is made up only half by the desired retarded solvent molecules in the hydration layer, but to another half by unretarded bulk water, so that measured relaxation times of the overall Stokes shift are only a lower boundary for the true relaxation times in the hydration layer of trehalose. As a side effect, the results on the effect of trehalose on solvation dynamics contribute to the long standing debate on the range of influence of

  11. Computational solvation dynamics of oxyquinolinium betaine linked to trehalose

    NASA Astrophysics Data System (ADS)

    Heid, Esther; Schröder, Christian

    2016-10-01

    Studying the changed water dynamics in the hydration layers of biomolecules is an important step towards fuller understanding of their function and mechanisms, but has shown to be quite difficult. The measurement of the time-dependent Stokes shift of a chromophore attached to the biomolecule is a promising method to achieve this goal, as published in Sajadi et al. [J. Phys. Chem. Lett., 5, 1845 (2014).] where trehalose was used as biomolecule, 1-methyl-6-oxyquinolinium betaine as chromophore, and water as solvent. An overall retardation of solvent molecules is then obtained by comparison of the linked system to the same system without trehalose, but contributions from different subgroups of solvent molecules, for example, molecules close to or far from trehalose, are unknown. The difficulty arising from these unknown contributions of retarded and possibly unretarded solvent molecules is overcome in this work by conducting computer simulations on this system and decomposing the overall signal into the contributions from various molecules at different locations. We performed non-equilibrium molecular dynamics simulation using a polarizable water model and a non-polarizable solute model and could reproduce the experimental time-dependent Stokes shift accurately for the linked trehalose-oxyquinolinium and the pure oxyquinolinium over a wide temperature range, indicating the correctness of our employed models. Decomposition of the shift into contributions from different solvent subgroups showed that the amplitude of the measured shift is made up only half by the desired retarded solvent molecules in the hydration layer, but to another half by unretarded bulk water, so that measured relaxation times of the overall Stokes shift are only a lower boundary for the true relaxation times in the hydration layer of trehalose. As a side effect, the results on the effect of trehalose on solvation dynamics contribute to the long standing debate on the range of influence of

  12. Magnetic signatures of Heinrich-like detrital layers in the Quaternary of the North Atlantic

    NASA Astrophysics Data System (ADS)

    Channell, J. E. T.; Hodell, D. A.

    2013-05-01

    Magnetic parameters are useful for distinguishing North Atlantic Heinrich-like detrital layers from background sediments. Here we compare magnetic properties with XRF scanning data back to 700 ka and 1.3 Ma at IODP Sites U1302-U1303 and U1308, respectively. Multi-domain magnetite, with grain sizes >20 µm, is characteristic of both Ca- and Si-rich detrital layers, as defined by XRF core scanning, confirming the contribution of ice rafting. Reflectance spectra and magnetic parameters distinguish Ca- and Si-rich IRD layers due the presence of high coercivity hematite in Si-rich layers. Heinrich layer 6 (H6) at Site U1302-U1303 is unlike other detrital layers, being marked by a 45-cm thick homogeneous cream-colored clay layer underlain by a thin (5-cm) graded coarse-sand. Comparison of Site U1302/03 and Site U1308 detrital layers implies a dominant Laurentide source for both Ca- and Si-rich detrital layers. At Site U1308, low benthic δ13C values during stadials are in-step with magnetic grain-size coarsening associated with Si-rich detrital layers back to 1.3 Ma, indicating a link between deep-sea ventilation and ice rafting. The surface-sediment tan-colored oxic layer (~2 m thick at Site U1308) yields magnetic hysteresis ratios that are offset from the single-domain to multi-domain (SD-MD) magnetite mixing-line in hysteresis-ratio diagrams. This offset is attributed to maghemite grain-coatings, that form on magnetite in surface sediment, and undergo dissolution as they pass through the oxic/anoxic boundary.

  13. Using Icebergs to Constrain Fjord Circulation and Link to Glacier Dynamics

    NASA Astrophysics Data System (ADS)

    Sutherland, D.; Straneo, F.; Hamilton, G. S.; Stearns, L. A.; Roth, G.

    2014-12-01

    The importance of icebergs is increasingly being recognized in the ocean-glacier interactions community. Icebergs are ubiquitous in Greenland's outlet glacial fjords and provide a physical link between the glacier and the ocean into which they melt. The iceberg shape is influenced by glacier size and calving mechanics, while the amount of melt produced depends on ambient water properties and the residence time of the iceberg in the fjord. Here, we use hourly positions of icebergs tracked with helicopter deployed GPS sensors to calculate velocities in the Sermilik Fjord/Helheim Glacier system. Data comes from three summertime deployments in 2012-2014, where icebergs were tagged in the ice mélange and moved through the fjord and onto the continental shelf. The iceberg-derived velocities provide information on ice mélange movement, fjord variability, and coastal currents on the shelf. Using simple melt rate parameterizations, we estimate the total freshwater input due to iceberg melt in Sermilik Fjord based on the observed residence times and satellite-derived iceberg distributions. These observations complement conventional oceanographic and glaciological data, and can quickly, and relatively inexpensively, characterize circulation throughout any given glacier-ocean system.

  14. LIF measurements of scalar mixing in turbulent shear layers

    NASA Technical Reports Server (NTRS)

    Karasso, Paris S.; Mungal, M. G.

    1993-01-01

    The structure of shear layer flows at high Reynolds numbers remains a very interesting problem. Straight mixing layers have been studied and yielded information on the probability density function (pdf) of a passive scalar across the layer. Konrad and Koochesfahani & Dimotakis measured the pdf of the mixture fraction for mixing layers of moderate Reynolds numbers, each about 25,000 (Re based on velocity difference and visual thickness). Their measurements showed a 'non-marching' pdf (central hump which is invariant from edge to edge across the layer), a result which is linked to the visualizations of the spanwise Kelvin-Helmholtz (K-H) instability mode, which is the primary instability for plane shear layer flows. A secondary instability mode, the Taylor-Gortler (T-G) instability, which is associated with streamwise vortical structures, has also been observed in shear layers. Image reconstruction by Jimenez et al. and volume renderings by Karasso & Mungal at low Re numbers have demonstrated that the K-H and the T-G instability modes occur simultaneously in a non-mutually destructive way, evidence that supports the quasi two-dimensional aspect of these flows and the non-marching character of the pdf at low Reynolds numbers. At higher Re numbers though, the interaction of these two instability modes is still unclear and may affect the mixing process. In this study, we perform measurements of the concentration pdf of plane mixing layers for different operating conditions. At a speed ratio of r = U(sub 1)/U(sub 2) = 4:1, we examine three Reynolds number cases: Re = 14,000, Re = 31,000, and Re = 62,000. Some other Re number cases' results, not presented in detail, are invoked to explain the behavior of the pdf of the concentration field. A case of r = 2.6:1 at Re = 20,000 is also considered. The planar laser-induced fluorescence technique is used to yield quantitative measurements. The different Re are obtained by changing the velocity magnitudes of the two streams. The

  15. A Description of Advertisements for Alcohol on LinkNYC Kiosks in Manhattan, New York City: A Pilot Study.

    PubMed

    Basch, Corey H; Ethan, Danna; LeBlanc, Michael; Basch, Charles E

    2018-02-26

    Excessive alcohol consumption compromises health and increases risk of mortality. Advertisements for alcohol in city environments have been shown to influence consumption. The aim of this pilot study was to estimate the prevalence of alcohol advertisements displayed on LinkNYC kiosks, a new communication channel that provides outdoor Wi-Fi access and advertising on streets within urban environments. Direct observations were conducted to document advertisements on a 20% random sample of the 500 LinkNYC kiosks in Manhattan, NYC. From May to September of 2017, each of the 100 selected kiosks was observed for a 10-min period to document advertisements for alcohol. In addition, differences in prevalence of alcohol advertisements were examined by the location of the kiosk based on NYC zip codes' median annual income. Of the 2025 advertisements observed, 5.09% (N = 103) were for an alcohol product (including duplicates). Such advertisements were observed on 17% of the kiosks. No health warnings or age warnings were presented in any of the alcohol advertisements. Compared with kiosks located in zip codes with lower median annual income, significantly more alcohol advertisements were displayed in zip codes with higher median annual income. This is the first study to estimate the prevalence of alcohol advertising on the LinkNYC Wi-Fi and telecommunication system, now ubiquitous on Manhattan's sidewalks. This study adds to the current literature that suggests New York City residents could benefit from health-promoting versus health-compromising advertising. The findings also highlight the potential of LinkNYC kiosk marketing to undermine health-related social marketing efforts by City government and other organizations.

  16. Effect of an isolated semi-arid pine forest on the boundary layer height

    NASA Astrophysics Data System (ADS)

    Brugger, Peter; Banerjee, Tirtha; Kröniger, Konstantin; Preisler, Yakir; Rotenberg, Eyal; Tatarinov, Fedor; Yakir, Dan; Mauder, Matthias

    2017-04-01

    Forests play an important role for earth's climate by influencing the surface energy balance and CO2 concentrations in the atmosphere. Semi-arid forests and their effects on the local and regional climate are studied within the CliFF project (Climate Feedbacks and benefits of semi-arid Forests). This requires understanding of the atmospheric boundary layer over semi-arid forests, because it links the surface and the free atmosphere and determines the exchange of momentum, heat and trace gases. Our study site, Yatir, is a semi-arid isolated pine forest in the Negev desert in Israel. Higher roughness and lower albedo compared to the surrounding shrubland make it interesting to study the influences of the semi-arid Yatir forest on the boundary layer. Previous studies of the forest focused on the energy balance and secondary circulations. This study focuses on the boundary layer structure above the forest, in particular the boundary layer height. The boundary layer height is an essential parameter for many applications (e.g. construction of convective scaling parameters or air pollution modeling). We measured the boundary layer height upwind, over and downwind of the forest. In addition we measured at two sites wind profiles within the boundary layer and turbulent fluxes at the surface. This allows us to quantify the effects of the forest on boundary layer compared to the surrounding shrubland. Results show that the forest increases the boundary layer height in absence of a strong boundary layer top inversion. A model of the boundary layer height based on eddy-covariance data shows some agreement to the measurements, but fails during anticyclonic conditions and the transition to the nocturnal boundary layer. More complex models accounting for large scale influences are investigated. Further influences of the forest and surrounding shrubland on the turbulent transport of energy are discussed in a companion presentation (EGU2017-2219).

  17. 3D morphological characterization of the polyamide active layer of RO and NF membranes using TEM and soft X-ray scattering

    NASA Astrophysics Data System (ADS)

    Culp, Tyler; Paul, Mou; Roy, Abhishek; Rosenberg, Steve; Behr, Michael; Kumar, Manish; Gomez, Enrique; Penn State Team; Dow Team

    Polyamide-based thin-film composite (TFC) membranes used for reverse osmosis (RO) and nanofiltration (NF) separation processes are at the forefront of water desalination and purification technologies due to their high salt rejection, high energy efficiency, and ease of operation. Nevertheless, in spite of the benefits of RO and NF membranes, many open questions about the internal nanostructure of the membrane active layer remain, such as the dispersion and distribution of acid functional groups. We demonstrate that resonant soft X-ray scattering (RSOXS), where the X-ray energy is tuned to absorption edges of the constituent materials, is a powerful tool to examine the microstructure of the polyamide layer. In conjunction with complementary techniques such as transmission electron microscopy (TEM), where tomography is used to obtain a 3D reconstruction of the polyamide active layer, the effect of cross-linking can be quantified in 3D for a systematic series of membranes. This relationship can then be applied to a series of commercially available RO and NF membranes where the effect of polyamide cross-linking on their respective structure and water transport properties can be evaluated. The combination of RSOXS with traditional characterization tools provides a strategy for linking the chemical structure to the morphology and water transport properties of RO and NF membranes.

  18. The Changing Face of Human-Computer Interaction in the Age of Ubiquitous Computing

    NASA Astrophysics Data System (ADS)

    Rogers, Yvonne

    HCI is reinventing itself. No longer only about being user-centered, it has set its sights on pastures new, embracing a much broader and far-reaching set of interests. From emotional, eco-friendly, embodied experiences to context, constructivism and culture, HCI research is changing apace: from what it looks at, the lenses it uses and what it has to offer. Part of this is as a reaction to what is happening in the world; ubiquitous technologies are proliferating and transforming how we live our lives. We are becoming more connected and more dependent on technology. The home, the crèche, outdoors, public places and even the human body are now being experimented with as potential places to embed computational devices, even to the extent of invading previously private and taboo aspects of our lives. In this paper, I examine the diversity of lifestyle and technological transformations in our midst and outline some 'difficult' questions these raise together with alternative directions for HCI research and practice.

  19. Ontological knowledge engine and health screening data enabled ubiquitous personalized physical fitness (UFIT).

    PubMed

    Su, Chuan-Jun; Chiang, Chang-Yu; Chih, Meng-Chun

    2014-03-07

    Good physical fitness generally makes the body less prone to common diseases. A personalized exercise plan that promotes a balanced approach to fitness helps promotes fitness, while inappropriate forms of exercise can have adverse consequences for health. This paper aims to develop an ontology-driven knowledge-based system for generating custom-designed exercise plans based on a user's profile and health status, incorporating international standard Health Level Seven International (HL7) data on physical fitness and health screening. The generated plan exposing Representational State Transfer (REST) style web services which can be accessed from any Internet-enabled device and deployed in cloud computing environments. To ensure the practicality of the generated exercise plans, encapsulated knowledge used as a basis for inference in the system is acquired from domain experts. The proposed Ubiquitous Exercise Plan Generation for Personalized Physical Fitness (UFIT) will not only improve health-related fitness through generating personalized exercise plans, but also aid users in avoiding inappropriate work outs.

  20. Ontological Knowledge Engine and Health Screening Data Enabled Ubiquitous Personalized Physical Fitness (UFIT)

    PubMed Central

    Su, Chuan-Jun; Chiang, Chang-Yu; Chih, Meng-Chun

    2014-01-01

    Good physical fitness generally makes the body less prone to common diseases. A personalized exercise plan that promotes a balanced approach to fitness helps promotes fitness, while inappropriate forms of exercise can have adverse consequences for health. This paper aims to develop an ontology-driven knowledge-based system for generating custom-designed exercise plans based on a user's profile and health status, incorporating international standard Health Level Seven International (HL7) data on physical fitness and health screening. The generated plan exposing Representational State Transfer (REST) style web services which can be accessed from any Internet-enabled device and deployed in cloud computing environments. To ensure the practicality of the generated exercise plans, encapsulated knowledge used as a basis for inference in the system is acquired from domain experts. The proposed Ubiquitous Exercise Plan Generation for Personalized Physical Fitness (UFIT) will not only improve health-related fitness through generating personalized exercise plans, but also aid users in avoiding inappropriate work outs. PMID:24608002