Air Keyboard: Mid-Air Text Input Using Wearable EMG Sensors and a Predictive Text Model

The human body is full of electrical signals. We propose to use the electric signals produced by the human body to input text without the use of a physical keyboard. We allow users to tap their fingers in the air as if typing on an imaginary keyboard. To detect the tapping, we created a wearable armband that uses electromyography (EMG) sensors to track individual finger muscle activation. Each finger is mapped to several characters, and based on the finger-sequence the user taps, a list of possible typed words is presented. Augmented reality and virtual reality headsets are becoming more prevalent (Oculus Rift, Microsoft Hololens, Google Cardboard, Magic Leap), and yet none of the existing typing techniques allow the user to easily input text while using these devices away from a desk. Giving users the ability to input text without using a physical keyboard opens up the possibility of using AR or VR in any location. We discuss the challenges in making our initial prototype more practical, robust, and reliable as part of our on-going research

What Effects Do Virtual Learning Tools Have on Preschoolers Kinesthetic Learning?

Technology is rapidly being integrated in most k-12 classrooms in California. Personal devices such as smartphones and tablets are becoming increasingly commonplace among children preschool age and younger. Early childhood educators are asking whether technology can accomplish the same learning goals of traditional hands on learning. This research study explores the effects of virtual learning using iPads in the preschool classroom. Using a pre-experimental design, children were tested using physical didactic materials, and then tested again using the same materials virtually on an iPad program. Using both quantitative and qualitative data, results of performance using both methods of instruction were inconclusive. However, the five year olds did show significantly lower scores using the iPad, indicating perhaps more familiarity with the physical materials. They also showed less frustration and better recall, indicating more maturity and readiness for new types of learning. When making decisions about technology in the preschool classroom, age and maturity of the child needs to be taken into account. Thoughtful consideration needs to be taken into account when using technology at the preschool level

Arterial-portal fistula treated with hepatic arterial embolization and portal venous aneurysm stent-graft exclusion complicated by type 2 endoleak.

Intrahepatic arterioportal fistulas may be complicated by portal hypertension. An associated portal venous aneurysm (PVA) may impinge upon adjacent structures or rupture. We present a 65-year-old man with an intrahepatic Intrahepatic arterioportal fistula and 6.4 × 5.8 cm right portal vein aneurysm extending within 0.4 cm of the hepatic margin, associated with pain concerning for impending rupture. The PVA was refractory to transarterial embolization due to recruitment of arterial collaterals. Therefore, it was additionally excluded from the portal vein with a 12 mm × 9.5 cm venous stent graft. Although endovascular therapy thrombosed the aneurysm and improved symptoms, it was complicated by a type 2 endoleak into the PVA

Why Do Cascade Sizes Follow a Power-Law?

We introduce random directed acyclic graph and use it to model the information diffusion network. Subsequently, we analyze the cascade generation model (CGM) introduced by Leskovec et al. [19]. Until now only empirical studies of this model were done. In this paper, we present the first theoretical proof that the sizes of cascades generated by the CGM follow the power-law distribution, which is consistent with multiple empirical analysis of the large social networks. We compared the assumptions of our model with the Twitter social network and tested the goodness of approximation.Comment: 8 pages, 7 figures, accepted to WWW 201

Starbursts versus Truncated Star Formation in Nearby Clusters of Galaxies

We present long-slit spectroscopy, B and R bandpass imaging, and 21 cm observations of a sample of early-type galaxies in nearby clusters which are known to be either in a star-forming phase or to have had star formation which recently terminated. From the long-slit spectra, obtained with the Blanco 4-m telescope, we find that emission lines in the star-forming cluster galaxies are significantly more centrally concentrated than in a sample of field galaxies. The broadband imaging reveals that two currently star-forming early-type galaxies in the Pegasus I cluster have blue nuclei, again indicating that recent star formation has been concentrated. In contrast, the two galaxies for which star formation has already ended show no central color gradient. The Pegasus I galaxy with the most evident signs of ongoing star formation (NGC7648), exhibits signatures of a tidal encounter. Neutral hydrogen observations of that galaxy with the Arecibo radiotelescope reveal the presence of ~4 x 10^8 solar masses of HI. Arecibo observations of other current or recent star-forming early-type galaxies in Pegasus I indicate smaller amounts of gas in one of them, and only upper limits in others.Comment: to be published in Astronomical Journa

Exploring Cross-Layer Dependencies in Congested Wireless Ad Hoc Networks

Steen, M.R. van [Promotor]Voulgaris, S. [Copromotor

Radial Color Gradients in K+A Galaxies in Distant Clusters of Galaxies

Galaxies in rich clusters with z $\gtrsim$ 0.3 are observed to have a higher fraction of photometrically blue galaxies than their nearby counterparts. This raises the important question of what environmental effects can cause the termination of star formation between z $\approx$ 0.3 and the present. The star formation may be truncated due to ram-pressure stripping, or the gas in the disk may be depleted by an episode of star formation caused by some external perturbation. To help resolve this issue, surface photometry was carried out for a total of 70 early-type galaxies in the cluster Cl1358+62, at z $\sim$ 0.33, using two-color images from the Hubble Archive. The galaxies were divided into two categories based on spectroscopic criteria: 24 are type K+A (e.g., strong Balmer lines, with no visible emission lines), while the remaining 46 are in the control sample with normal spectra. Radial color profiles were produced to see if the K+A galaxies show bluer nuclei in relation to their surrounding disks. Specifically, a linear gradient was fit to the radial color profile of each galaxy. We find that the K+A galaxies on average tend to have slightly bluer gradients towards the center than the normals. A Kolmogorov-Smirnov two-sample test has been applied to the two sets of color gradients. The result of the test indicates that there is only a $\sim$2% probability that the K+A and normal samples are drawn from the same parent distribution. There is a possible complication from a trend in the apparent magnitude vs. color gradient relation, but overall our results favor the centralized star formation scenario as an important process in the evolution of galaxies in dense clusters.Comment: 16 pages, 12 figures, accepted for publication in A

Physical modelling of lime stabilisation in soft soils around deep excavations

Bored concrete piles have been used widely on commercial developments in London for about the last 50 years. The life of a commercial building is between 25 – 30 years and, as each building is demolished and rebuilt, the piles from the previous buildings remain in the ground causing obstruct ions to the new foundations. This paper describes a preliminary study to explore the viability of sheet piled foundations as a genuine alternative to cast in situ concrete piles and all of the complications inherent in their construction and the obstruction they create to subsequent foundations. If it is possible to u se steel piles as foundations they can be easily removed, recycled and will not cause obstructions for future developments. However, individual sheet piles have relatively low capacity when axially loaded and it is therefore necessary to consider a sheet p ile grou p in conjunction with a pilecap, which can be considered a hybrid foundation; a combination of shallow (pilecap) and deep (sheet pile). A short series of centrifuge tests is reported in which model sheet pile groups in over - consolidated clay were l oaded axially whilst vertical displacements were measured. Equivalent cast in place piles were similarly tested alongside the sheet pile groups by way of comparison

New observational method framework and application

© 2017 19th ICSMGE Secretariat. All rights reserved. This paper introduces the new holistic Observational Method (OM) framework described in Ciria C760 -the new revision to the Embedded Retaining Wall Design Guide. This new OM framework is described by four approaches and these are explained with reference to case histories. Maximum benefit is achieved by back analyzing case histories in similar ground conditions to derive the most probable soil parameters. These parameters can then be used in an ab initio design to maximize saving in the wall thickness, toe embedment, and propping forces. A contingency plan is based on conventional characteristic design parameters and this involves additional propping. The term ipso tempore is introduced to cover wall redesign after construction starts. This may be to achieve saving in propping where movements are smaller than predicted. Alternatively, additional propping or ground treatment may be required and this is consistent with Peck's 'best way out' approach.Ove Arup Lt