scholarly journals Fine-grained LTE radio link estimation for mobile phones

Author(s):  
Nicola Bui ◽  
Foivos Michelinakis ◽  
Joerg Widmer
2018 ◽  
Vol 49 ◽  
pp. 76-91
Author(s):  
Nicola Bui ◽  
Foivos Michelinakis ◽  
Joerg Widmer

Technologies ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 45
Author(s):  
Alexander V. Mantzaris ◽  
Randyll Pandohie ◽  
Michael Hopwood ◽  
Phuong Pho ◽  
Dustin Ehling ◽  
...  

Digital cameras and mobile phones have given people around the world the ability to take a large number of photos and store them on their computers. As these images serve the purpose of storing memories and bringing them to mind in the potentially far future, it is important to also store the impressions a user may have from them. Annotating these images can be a laborious process and the work here presents an application design and functioning implementation, which is openly available now, to ease the effort of this task. It also draws inspiration from interface developments of previous applications such as the Nokia Lifeblog and the Facebook user interface. A different mode of sentiment entry is provided where users interact with slider widgets rather than select a emoticon from a set to offer a more fine grained value. Special attention is made to avoid cognitive strain by avoiding nested tool selections.


Author(s):  
Anne Hardy

Research that tracks tourists’ movement challenges our perception of ethics, privacy, and consent. The introduction of technology with the capability to track tourists in fine grained detail is viewed by some as a gross invasion of privacy, by others as a personal safety mechanism, and is treated by others with almost complete ambivalence. Importantly, in the past fifteen years we have witnessed a great change in the way in which tracking has been viewed by study participants and the general public, along with many mysterious contradictions in our acceptance or resistance to privacy – possibly fuelled by media attention around this issue. In the early 2000s, apps began emerging that conducted GPS tracking covertly in the background. For example, flash light applications (henceforth referred to as ‘apps’) that many of us had on our mobile phones, appeared to be a useful app. However, the business model of these apps was that they tracked users’ movements in the background of the app and on-sold this data to marketing companies. Similarly, The Weather Channel app was recently exposed for on-selling tracking data that was covertly collected, resulting in a legal case against its owner, IBM. In 2017, it was estimated that 70% of apps track and share user information with third parties (Vallina-Roderigue and Sundaresan, 2017). While there is resistance to some forms of tracking, there appears to be acceptance of other types. Strava is one such example. It is estimated that each week, 8 million activities are uploaded onto the app (Goode, 2017). Every 40 days, the app adds one million users (Craft, 2018). It is used by recreational hikers, bikers and runners, who wish to track and share their activities. It is widely known that the business model of Strava is built upon on-selling this data to cities and councils. This practice seems to be widely accepted by users.


Author(s):  
Lei Wang ◽  
Xiang Zhang ◽  
Yuanshuang Jiang ◽  
Yong Zhang ◽  
Chenren Xu ◽  
...  

Gesture recognition on the back surface of mobile phone, not limited to the touch screen, is an enabling Human-Computer Interaction (HCI) mechanism which enriches the user interaction experiences. However, there are two main limitations in the existing Back-of-Device (BoD) gesture recognition systems. They can only handle coarse-grained gesture recognition such as tap detection and cannot avoid the air-borne propagation suffering from the interference in the air. In this paper, we propose StruGesture, a fine-grained gesture recognition system using the back of mobile phones with ultrasonic signals. The key technique is to use the structure-borne sounds (i.e., sound propagation via structure of the device) to recognize sliding gestures on the back of mobile phones. StruGesture can fully extract the structure-borne component from the hybrid Channel Impulse Response (CIR) based on Peak Selection Algorithm. We develop a deep adversarial learning architecture to learn the gesture-specific representation for robust and effective recognition. Extensive experiments are designed to evaluate the robustness over nine deployment scenarios. The results show that StruGesture outperforms the competitive state-of-the-art classifiers by achieving an average recognition accuracy of 99.5% over 10 gestures.


Author(s):  
Richard S. Chemock

One of the most common tasks in a typical analysis lab is the recording of images. Many analytical techniques (TEM, SEM, and metallography for example) produce images as their primary output. Until recently, the most common method of recording images was by using film. Current PS/2R systems offer very large capacity data storage devices and high resolution displays, making it practical to work with analytical images on PS/2s, thereby sidestepping the traditional film and darkroom steps. This change in operational mode offers many benefits: cost savings, throughput, archiving and searching capabilities as well as direct incorporation of the image data into reports.The conventional way to record images involves film, either sheet film (with its associated wet chemistry) for TEM or PolaroidR film for SEM and light microscopy. Although film is inconvenient, it does have the highest quality of all available image recording techniques. The fine grained film used for TEM has a resolution that would exceed a 4096x4096x16 bit digital image.


Author(s):  
Steven D. Toteda

Zirconia oxygen sensors, in such applications as power plants and automobiles, generally utilize platinum electrodes for the catalytic reaction of dissociating O2 at the surface. The microstructure of the platinum electrode defines the resulting electrical response. The electrode must be porous enough to allow the oxygen to reach the zirconia surface while still remaining electrically continuous. At low sintering temperatures, the platinum is highly porous and fine grained. The platinum particles sinter together as the firing temperatures are increased. As the sintering temperatures are raised even further, the surface of the platinum begins to facet with lower energy surfaces. These microstructural changes can be seen in Figures 1 and 2, but the goal of the work is to characterize the microstructure by its fractal dimension and then relate the fractal dimension to the electrical response. The sensors were fabricated from zirconia powder stabilized in the cubic phase with 8 mol% percent yttria. Each substrate was sintered for 14 hours at 1200°C. The resulting zirconia pellets, 13mm in diameter and 2mm in thickness, were roughly 97 to 98 percent of theoretical density. The Engelhard #6082 platinum paste was applied to the zirconia disks after they were mechanically polished ( diamond). The electrodes were then sintered at temperatures ranging from 600°C to 1000°C. Each sensor was tested to determine the impedance response from 1Hz to 5,000Hz. These frequencies correspond to the electrode at the test temperature of 600°C.


Author(s):  
J. W. Mellowes ◽  
C. M. Chun ◽  
I. A. Aksay

Mullite (3Al2O32SiO2) can be fabricated by transient viscous sintering using composite particles which consist of inner cores of a-alumina and outer coatings of amorphous silica. Powder compacts prepared with these particles are sintered to almost full density at relatively low temperatures (~1300°C) and converted to dense, fine-grained mullite at higher temperatures (>1500°C) by reaction between the alumina core and the silica coating. In order to achieve complete mullitization, optimal conditions for coating alumina particles with amorphous silica must be achieved. Formation of amorphous silica can occur in solution (homogeneous nucleation) or on the surface of alumina (heterogeneous nucleation) depending on the degree of supersaturation of the solvent in which the particles are immersed. Successful coating of silica on alumina occurs when heterogeneous nucleation is promoted and homogeneous nucleation is suppressed. Therefore, one key to successful coating is an understanding of the factors such as pH and concentration that control silica nucleation in aqueous solutions. In the current work, we use TEM to determine the optimal conditions of this processing.


Author(s):  
C. P. Doğan ◽  
R. D. Wilson ◽  
J. A. Hawk

Capacitor Discharge Welding is a rapid solidification technique for joining conductive materials that results in a narrow fusion zone and almost no heat affected zone. As a result, the microstructures and properties of the bulk materials are essentially continuous across the weld interface. During the joining process, one of the materials to be joined acts as the anode and the other acts as the cathode. The anode and cathode are brought together with a concomitant discharge of a capacitor bank, creating an arc which melts the materials at the joining surfaces and welds them together (Fig. 1). As the electrodes impact, the arc is extinguished, and the molten interface cools at rates that can exceed 106 K/s. This process results in reduced porosity in the fusion zone, a fine-grained weldment, and a reduced tendency for hot cracking.At the U.S. Bureau of Mines, we are currently examining the possibilities of using capacitor discharge welding to join dissimilar metals, metals to intermetallics, and metals to conductive ceramics. In this particular study, we will examine the microstructural characteristics of iron-aluminum welds in detail, focussing our attention primarily on interfaces produced during the rapid solidification process.


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