scholarly journals Smartphone-Based User Positioning in a Multiple-User Context with Wi-Fi and Bluetooth

2018 ◽  
Author(s):  
Viet-Cuong Ta ◽  
Trung-Kien Dao ◽  
Dominique Vaufreydaz ◽  
Eric Castelli
Keyword(s):  
Multiple User ◽  
User Context

scholarly journals On Using Multiple Disabilities Profiles to Adapt Multimedia Documents

2020 ◽  
Vol 15 (3) ◽  
pp. 34-60
Author(s):  
Asma Saighi ◽  
Zakaria Laboudi ◽  
Philippe Roose ◽  
Sébastien Laborie ◽  
Nassira Ghoualmi-Zine
Keyword(s):  
Experimental Study ◽  
Mobile Device ◽  
Multiple Disabilities ◽  
Multimedia Content ◽  
Multimedia Documents ◽  
Physical Handicap ◽  
Multiple User ◽  
User Context ◽  
Adaptation Action ◽  
Context Constraints

Currently, advanced technological hardware can offer mobile devices which fits in the hand with a capacity to consult documents at anytime and anywhere. Multiple user context constraints as well as mobile device capabilities may involve the adaptation of multimedia content. In this article, the authors propose a new graph-based method for adapting multimedia documents in complex situations. Each contextual situation could correspond to a physical handicap and therefore triggers an adaptation action using ontological reasoning. Consequently, when several contextual situations are identified, this leads to multiple disabilities and may give rise to inconsistency between triggered actions. Their method allows modeling relations between adaptation-actions to select the compatible triggerable ones. In order to evaluate the feasibility and the performance of their proposal, an experimental study has been made on some real scenarios. When tested and compared with some existing approaches, their proposal showed improvements according to various criteria.

scholarly journals On Using Multiple Disabilities Profiles to Adapt Multimedia Documents

2022 ◽  
pp. 173-201
Author(s):  
Asma Saighi ◽  
Zakaria Laboudi ◽  
Philippe Roose ◽  
Sébastien Laborie ◽  
Nassira Ghoualmi-Zine
Keyword(s):  
Experimental Study ◽  
Mobile Device ◽  
Multiple Disabilities ◽  
Multimedia Content ◽  
Multimedia Documents ◽  
Physical Handicap ◽  
Multiple User ◽  
User Context ◽  
Adaptation Action ◽  
Context Constraints

Currently, advanced technological hardware can offer mobile devices which fits in the hand with a capacity to consult documents at anytime and anywhere. Multiple user context constraints as well as mobile device capabilities may involve the adaptation of multimedia content. In this article, the authors propose a new graph-based method for adapting multimedia documents in complex situations. Each contextual situation could correspond to a physical handicap and therefore triggers an adaptation action using ontological reasoning. Consequently, when several contextual situations are identified, this leads to multiple disabilities and may give rise to inconsistency between triggered actions. Their method allows modeling relations between adaptation-actions to select the compatible triggerable ones. In order to evaluate the feasibility and the performance of their proposal, an experimental study has been made on some real scenarios. When tested and compared with some existing approaches, their proposal showed improvements according to various criteria.

scholarly journals Collaborative Smartphone-Based User Positioning in a Multiple-User Context Using Wireless Technologies

Sensors ◽  
2020 ◽  
Vol 20 (2) ◽  
pp. 405 ◽  
Author(s):  
Viet-Cuong Ta ◽  
Trung-Kien Dao ◽  
Dominique Vaufreydaz ◽  
Eric Castelli
Keyword(s):  
Error Function ◽  
Indoor Environments ◽  
Additional Information ◽  
Multiple User ◽  
User Context ◽  
Average Accuracy ◽  
Time Component ◽  
Observation Function ◽  
Set Up ◽  
Error Observation

For the localization of multiple users, Bluetooth data from the smartphone is able to complement Wi-Fi-based methods with additional information, by providing an approximation of the relative distances between users. In practice, both positions provided by Wi-Fi data and relative distance provided by Bluetooth data are subject to a certain degree of noise due to the uncertainty of radio propagation in complex indoor environments. In this study, we propose and evaluate two approaches, namely Non-temporal and Temporal ones, of collaborative positioning to combine these two cohabiting technologies to improve the tracking performance. In the Non-temporal approach, our model establishes an error observation function in a specific interval of the Bluetooth and Wi-Fi output. It is then able to reduce the positioning error by looking for ways to minimize the error function. The Temporal approach employs an extended error model that takes into account the time component between users’ movements. For performance evaluation, several multi-user scenarios in an indoor environment are set up. Results show that for certain scenarios, the proposed approaches attain over 40% of improvement in terms of average accuracy.

Plug-in scripts for EFTEM automation

1996 ◽  
Vol 54 ◽  
pp. 546-547
Author(s):  
N. D. Evans ◽  
M. K. Kundmann
Keyword(s):  
Electron Microscopy ◽  
National Laboratory ◽  
Oak Ridge ◽  
Multiple User ◽  
Transmission Electron ◽  
Short Period ◽  
User Facility ◽  
Instrument Control ◽  
And Control ◽  
Research Equipment

Post-column energy-filtered transmission electron microscopy (EFTEM) is inherently challenging as it requires the researcher to setup, align, and control both the microscope and the energy-filter. The software behind an EFTEM system is therefore critical to efficient, day-to-day application of this technique. This is particularly the case in a multiple-user environment such as at the Shared Research Equipment (SHaRE) User Facility at Oak Ridge National Laboratory. Here, visiting researchers, who may oe unfamiliar with the details of EFTEM, need to accomplish as much as possible in a relatively short period of time.We describe here our work in extending the base software of a commercially available EFTEM system in order to automate and streamline particular EFTEM tasks. The EFTEM system used is a Philips CM30 fitted with a Gatan Imaging Filter (GIF). The base software supplied with this system consists primarily of two Macintosh programs and a collection of add-ons (plug-ins) which provide instrument control, imaging, and data analysis facilities needed to perform EFTEM.

Serial thin sectioning for pre- and post-embedding immunohistochemistry: Achieving consistent and reliable results for a 3-D reconstruction

1993 ◽  
Vol 51 ◽  
pp. 328-329
Author(s):  
Antonia M. Milroy
Keyword(s):  
Nervous System ◽  
Computer Assisted ◽  
Serial Sectioning ◽  
Electron Microscopic ◽  
High Quality ◽  
New Techniques ◽  
3 Dimensional ◽  
Multiple User ◽  
Thin Sectioning ◽  
Subcellular Level

In recent years many new techniques and instruments for 3-Dimensional visualization of electron microscopic images have become available. Higher accelerating voltage through thicker sections, photographed at a tilt for stereo viewing, or the use of confocal microscopy, help to analyze biological material without the necessity of serial sectioning. However, when determining the presence of neurotransmitter receptors or biochemical substances present within the nervous system, the need for good serial sectioning (Fig. 1+2) remains. The advent of computer assisted reconstruction and the possibility of feeding information from the specimen viewing chamber directly into a computer via a camera mounted on the electron microscope column, facilitates serial analysis. Detailed information observed at the subcellular level is more precise and extensive and the complexities of interactions within the nervous system can be further elucidated.We emphasize that serial ultra thin sectioning can be performed routinely and consistently in multiple user electron microscopy laboratories. Initial tissue fixation and embedding must be of high quality.

Performance Enhancement of Encoding–Decoding Multidiagonal and Walsh Hadamard Codes for Spectral Amplitude Coding-Optical Code Division Multiple Access (SAC-OCDMA) Utilizing Dispersion Compensated Fiber

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Majidah H. Majeed ◽  
Riyadh Khlf Ahmed
Keyword(s):  
Multiple Access ◽  
Performance Enhancement ◽  
Optical Network ◽  
Spectral Amplitude ◽  
Q Factor ◽  
Data Traffic ◽  
Eye Diagram ◽  
Multiple User ◽  
Spectral Amplitude Coding ◽  
Code Division Multiple

AbstractSpectral Amplitude Coding-Optical Codes Division Multiple Access (SAC-OCDMA) is a future multiplexing technique that witnessed a dramatic attraction for eliminating the problems of the internet in optical network field such as multiple-user access and speed’s growth of the files or data traffic. In this research article, the performance of SAC-OCDMA system based on two encoding–decoding multidiagonal (MD) and Walsh Hadamard (WH) codes is enhanced utilizing three different schemes of dispersion compensating fiber (DCF): pre-, post- and symmetrical compensation. The system is simulated using Optisystem version 7.0 and Optigrating version 4.2. The performance of the proposed system is specified in terms of bit error rate (BER), Q-factor and eye diagram. It has been observed that the compensated system based on MD code is performs much better compared to the system based on WH code. On the other hand, the compensated SAC-OCDMA system with symmetrical DCF has the lowest values of BER and largest values of Q-factor, so it is considered the best simulated scheme contrasted with pre- and post-DCF.

scholarly journals Optimal Multi-Antenna Transmission for the Cooperative Non-Orthogonal Multiple-Access System

2021 ◽  
Vol 11 (5) ◽  
pp. 2203
Author(s):  
Duckdong Hwang ◽  
Janghoon Yang ◽  
Sung Sik Nam ◽  
Hyoung-Kyu Song
Keyword(s):  
Interference Cancellation ◽  
Multiple Access ◽  
Average Power ◽  
Access Point ◽  
Power Performance ◽  
Multiple User ◽  
Structure Simulation ◽  
Rank One ◽  
Multiple Access System ◽  
Optimal Beamforming

We investigate the beamforming for the multi antenna cooperative non-orthogonal multiple access (NOMA) system, where an access point (AP) delivers messages for multiple user terminals (UT) with successive interference cancellation (SIC) reception method. Some UTs with multiple antennas cooperate with the AP transmission to improve the diversity and the average power performance. We formally present two optimal beamforming schemes at the AP and at the cooperative UTs. One scheme has no power limitation for the cooperative UTs, while the other one does have such limitation. We guarantee that the rank one beamformer is sufficient to achieve the optimal points so that the proposed schemes have rank one semi-definite programming (SDP) structure. Simulation results show the performance gain of the multi-antenna cooperative NOMA schemes in the sense of diversity and the average power.

scholarly journals The State of Speech in HCI: Trends, Themes and Challenges

2019 ◽  
Vol 31 (4) ◽  
pp. 349-371 ◽  
Author(s):  
Leigh Clark ◽  
Philip Doyle ◽  
Diego Garaialde ◽  
Emer Gilmartin ◽  
Stephan Schlögl ◽  
...  
Keyword(s):  
Speech Production ◽  
Thematic Analysis ◽  
Design Work ◽  
Wizard Of Oz ◽  
Speech Interfaces ◽  
Interface Interaction ◽  
Multiple User ◽  
Speech Interface ◽  
User Attitudes ◽  
In The Wild

AbstractSpeech interfaces are growing in popularity. Through a review of 99 research papers this work maps the trends, themes, findings and methods of empirical research on speech interfaces in the field of human–computer interaction (HCI). We find that studies are usability/theory-focused or explore wider system experiences, evaluating Wizard of Oz, prototypes or developed systems. Measuring task and interaction was common, as was using self-report questionnaires to measure concepts like usability and user attitudes. A thematic analysis of the research found that speech HCI work focuses on nine key topics: system speech production, design insight, modality comparison, experiences with interactive voice response systems, assistive technology and accessibility, user speech production, using speech technology for development, peoples’ experiences with intelligent personal assistants and how user memory affects speech interface interaction. From these insights we identify gaps and challenges in speech research, notably taking into account technological advancements, the need to develop theories of speech interface interaction, grow critical mass in this domain, increase design work and expand research from single to multiple user interaction contexts so as to reflect current use contexts. We also highlight the need to improve measure reliability, validity and consistency, in the wild deployment and reduce barriers to building fully functional speech interfaces for research.RESEARCH HIGHLIGHTSMost papers focused on usability/theory-based or wider system experience research with a focus on Wizard of Oz and developed systems Questionnaires on usability and user attitudes often used but few were reliable or validated Thematic analysis showed nine primary research topics Challenges identified in theoretical approaches and design guidelines, engaging with technological advances, multiple user and in the wild contexts, critical research mass and barriers to building speech interfaces

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