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41.
Stuart Moran Nils Jäger Holger Schnädelbach Kevin Glover 《Personal and Ubiquitous Computing》2016,20(2):261-275
Both breathing and internal self-awareness are an integral part of any yoga practice. We describe and discuss the development of ExoPranayama, an actuated environment that physically manifests users’ breathing in yoga. Through a series of trials with yoga practitioners and expert teachers, we explore its role in the practice of yoga. Our interview results reveal that biofeedback through the environment supported teaching and improved self-awareness, but it impacted group cohesion. Two practical uses of the technology emerged for supporting breath control in yoga: (1) biofeedback can provide new information about users’ current internal states; (2) machine-driven feedback provides users with a future state or goal and leads to improved cohesiveness. 相似文献
42.
43.
Kevin Curran Michelle Murray David Stephen Norrby Martin Christian 《New Review of Information Networking》2013,18(1-2):47-59
Libraries, as we know them today, can be defined by the term Library 1.0. This defines the way resources are kept on shelves or at a computer behind a login. These resources can be taken from a shelf, checked out by the library staff, taken home for a certain length of time and absorbed, and then returned to the library for someone else to avail of. Library 1.0 is a one-directional service that takes people to the information they require. Library 2.0 – or L2 as it is now more commonly addressed as – aims to take the information to the people by bringing the library service to the Internet and getting the users more involved by encouraging feedback participation. This paper presents an overview of Library 2.0 and introduces web 2.0 concepts. 相似文献
44.
Jonathan A. Czuba James L. Best Kevin A. Oberg Daniel R. Parsons P. Ryan Jackson Marcelo H. Garcia Peter Ashmore 《Journal of Great Lakes research》2011,37(3):480-493
An integrated multibeam echo sounder and acoustic Doppler current profiler field survey was conducted in July 2008 to investigate the morphodynamics of the St. Clair River at the outlet of Lake Huron. The principal morphological features of the upper St. Clair River included flow-transverse bedforms that appear weakly mobile, erosive bedforms in cohesive muds, thin non-cohesive veneers of weakly mobile sediment that cover an underlying cohesive (till or glacio-lacustrine) surface, and vegetation that covers the bed. The flow was characterized by acceleration as the banks constrict from Lake Huron into the St. Clair River, an approximately 1500-m long region of flow separation downstream from the Blue Water Bridge, and secondary flow connected to: i) channel curvature; ii) forcing of the flow by local bed topography, and iii) flow wakes in the lee side of ship wrecks. Nearshore, sand-sized, sediment from Lake Huron was capable of being transported into, and principally along, the banks of the upper St. Clair River by the measured flow. A comparison of bathymetric surveys conducted in 2007 and 2008 identifies that the gravel bed does undergo slow downstream movement, but that this movement does not appear to be generated by the mean flow, and could possibly be caused by ship-propeller-induced turbulence. The study results suggest that the measured mean flow and dredging within the channel have not produced major scour of the upper St. Clair River and that the recent fall in the level of Lake Huron is unlikely to have been caused by these mechanisms. 相似文献
45.
Wenjing Wang Shameek Bhattacharjee Mainak Chatterjee Kevin Kwiat 《Pervasive and Mobile Computing》2013,9(4):572-587
In cognitive radio networks, cognitive nodes operate on a common pool of spectrum where they opportunistically access and use parts of the spectrum not being used by others. Though cooperation among nodes is desirable for efficient network operations and performance, there might be some malicious nodes whose objective could be to hinder communications and disrupt network operations. The absence of a central authority or any policy enforcement mechanism makes these kinds of open-access network more vulnerable and susceptible to attacks.In this paper, we analyze a common form of denial-of-service attack, i.e., collaborative jamming. We consider a network in which a group of jammers tries to jam the channels being used by legitimate users who in turn try to evade the jammed channels. First, we compute the distribution of the jamming signal that a node experiences by considering a random deployment of jammers. Then, we propose different jamming and defending schemes that are employed by the jammers and legitimate users, respectively. In particular, we model and analyze the channel availability when the legitimate users randomly choose available channels and the jammers jam different channels randomly. We propose a multi-tier proxy-based cooperative defense strategy to exploit the temporal and spatial diversity for the legitimate secondary users in an infrastructure-based centralized cognitive radio network. Illustrative results on spectrum availability rates show how to improve resiliency in cognitive radio networks in the presence of jammers. 相似文献
46.
最近,一家厂商的自动润滑系统在人为地进行了一次未知的定时改动之后,损失了超过100,000美元与停工相关的费用。一个定时器之前是每20分钟注入一次润滑油,后来被设定为每8小时注入一次润滑油,导致机械轴承需要进行一次提前到来的改装。 相似文献
47.
Michael M. Li Brijesh Verma Xiaolong Fan Kevin Tickle 《Neural computing & applications》2008,17(4):391-397
This paper investigates a new method to solve the inverse problem of Rutherford backscattering (RBS) data. The inverse problem
is to determine the sample structure information from measured spectra, which can be defined as a function approximation problem.
We propose using radial basis function (RBF) neural networks to approximate an inverse function. Each RBS spectrum, which
may contain up to 128 data points, is compressed by the principal component analysis, so that the dimensionality of input
data and complexity of the network are reduced significantly. Our theoretical consideration is tested by numerical experiments
with the example of the SiGe thin film sample and corresponding backscattering spectra. A comparison of the RBF method with
multilayer perceptrons reveals that the former has better performance in extracting structural information from spectra. Furthermore,
the proposed method can handle redundancies properly, which are caused by the constraint of output variables. This study is
the first method based on RBF to deal with the inverse RBS data analysis problem. 相似文献
48.
英国电信是第一个吹响转型号角的传统电信公司,也是第一家提出做“综合信息服务提供商”的运营商。目前它已经牢固确立了其作为网络IT解决方案提供商的核心定位。在全球经济危机蔓延,金融风暴影响实体经济的当下,作为经济结构中承担基础性架构角色的电信行业面临前所未有的挑战与机遇。英国电信(BT)清醒的认识到了这一点,借助IT与网络、数据与通讯融合的趋势浪潮,英国电信正在开启亚太市场的大门。 相似文献
49.
Jenkins RE Meng X Elliott VL Kitteringham NR Pirmohamed M Park BK 《Proteomics. Clinical applications》2009,3(6):720-729
Flucloxacillin is a synthetic penicillin used in the treatment of Staphylococcal infections. Adverse reactions to the drug are believed to arise through covalent modification of proteins, with tissue damage occurring secondary to an immune reaction. Serum proteins have been shown by adduct-specific antibodies to be modified by flucloxacillin, but the nature and sites of modification have not been characterised. Here, in vitro studies on HSA have shown by MS that the modification of protein lysine residues occurs in a dose-, time- and site-dependent manner. Affinity, cation exchange and reversed phase chromatography prior to MS revealed in vivo modification of HSA with flucloxacillin in tolerant patients, with up to nine modified lysine residues being detected in each patient, and with modification of Lys190 and Lys212 being detected in 8/8 patients. It was also revealed for the first time that plasma proteins could be modified with the 5-hydroxymethyl metabolite of flucloxacillin, and that essentially the same Lys residues were targeted by both the parent drug and its metabolite. This study provides a detailed characterisation of sites of chemical modification of an endogenous target and reveals candidate peptides for T-cell and antibody assays of flucloxacillin hypersensitivity. 相似文献
50.
Distance learning's interfaces—from corresponding through the postal service to the televised talking head—have traditionally been designed from the top down, supporting banking models of learning or, in writing instruction, current-traditional rhetoric pedagogies. Due to temporal and spatial constraints, these interface designs often support (or encourage) one-way communication from the instructor to the student. Students mostly interact with the instructor by asking questions or submitting work, and they tend to have little correspondence with other peers. These methods clearly privilege the instructor's knowledge and evaluation. Furthermore, these interface designs empower the instructor to gaze upon the students and assess them—often not as a corporeal body but as a corpus of texts. Thus, each interface adopted for distance learning sets up a power dynamic in which the capability to share the roles of creating knowledge is juxtaposed with the instructor's capability to normalize the students and reify their own authority through their gaze. In this article we examine the traditional classroom interface through the correspondence course interface, the simulated classroom interface, and the synchronous video interface to raise questions about the infrastructures of distance learning and their implications for student learning. 相似文献