441 research outputs found
Mid-Air Haptics for Control Interfaces
Control interfaces and interactions based on touch-less gesture tracking devices have become a prevalent research topic in both industry and academia. Touch-less devices offer a unique interaction immediateness that makes them ideal for applications where direct contact with a physical controller is not desirable. On the other hand, these controllers inherently lack active or passive haptic feedback to inform users about the results of their interaction. Mid-air haptic interfaces, such as those using focused ultrasound waves, can close the feedback loop and provide new tools for the design of touch-less, un-instrumented control interactions. The goal of this workshop is to bring together the growing mid-air haptic research community to identify and discuss future challenges in control interfaces and their application in AR/VR, automotive, music, robotics and teleoperation
Biomarkers of Oxidative Stress and Endogenous Antioxidants for Patients with Chronic Subjective Dizziness
As a neurotologic disorder of persistent non-vertiginous dizziness, chronic subjective dizziness (CSD) arises unsteadily by psychological and physiological imbalance. The CSD is hypersensitivity reaction due to exposure to complex motions visual stimuli. However, the pathophysiological features and mechanism of the CSD still remains unclearly. The present study was purposed to establish possible endogenous contributors of the CSD using serum samples from patients with the CSD. A total 199 participants were gathered and divided into two groups; healthy (n = 152, male for 61, and female for 91) and CSD (n = 47, male for 5, female for 42), respectively. Oxidative stress parameters such as, hydrogen peroxide and reactive substances were significantly elevated (p < 0.01 or p < 0.001), whereas endogenous antioxidant components including total glutathione contents, and activities of catalase and superoxide dismutase were significantly deteriorated in the CSD group (p < 0.01 or p < 0.001) as comparing to the healthy group, respectively. Serum levels of tumor necrosis factor -α and interferon-γ were significantly increased in the CSD participants (p < 0.001). Additionally, emotional stress related hormones including cortisol, adrenaline, and serotonin were abnormally observed in the serum levels of the CSD group (p < 0.01 or p < 0.001). Our results confirmed that oxidative stress and antioxidants are a critical contributor of pathophysiology of the CSD, and that is first explored to establish features of redox system in the CSD subjects compared to a healthy population
Effect of Information Content in Sensory Feedback on Typing Performance using a Flat Keyboard
Abstract-We investigate the effect of information content in sensory feedback on typing performance using a flat keyboard. We build a flat keyboard apparatus with haptic and auditory keyclick feedback. We evaluate and compare typing performance with key-press confirmation and key-correctness information through sensory feedback. Twelve participants are asked to touch-type a number of randomly selected phrases under various combinations of visual, auditory and haptic sensory feedback conditions. The results show that typing speed is not significantly affected by the information content in sensory feedback, but the uncorrected error rate is significantly lower when key-correctness information is available. The results also show that key-correctness information leads to more corrected errors and lowers typing efficiency. Our findings are useful for developing flat keyboards with assistive information through sensory feedback. Our study is the first step towards improving typing performance on flat keyboards by delivering more advanced and comprehensive assistive information beyond the visual channel
Interfacial architecture for extra Li+ storage in all-solid-state lithium batteries
The performance of nanocomposite electrodes prepared by controlled ball-milling of TiS2 and a Li2S-P2S5 solid electrolyte (SE) for all-solid-state lithium batteries is investigated, focusing on the evolution of the microstructure. Compared to the manually mixed electrodes, the ball-milled electrodes exhibit abnormally increased first-charge capacities of 416 mA h g-1and 837 mA h g-1 in the voltage ranges 1.5-3.0 V and 1.0-3.0 V, respectively, at 50 mA g-1 and 30??C. The ball-milled electrodes also show excellent capacity retention of 95% in the 1.5-3.0 V range after 60 cycles as compared to the manually mixed electrodes. More importantly, a variety of characterization techniques show that the origin of the extra Li+ storage is associated with an amorphous Li-Ti-P-S phase formed during the controlled ball-milling process.open1
Dissecting Video Server Selection Strategies in the YouTube CDN
In this paper, we conduct a detailed study of theYouTube CDN with a view to understanding the mechanismsand policies used to determine which data centers users downloadvideo from. Our analysis is conducted using week-long datasetssimultaneously collected from the edge of five networks - twouniversity campuses and three ISP networks - located in threedifferent countries. We employ state-of-the-art delay-based geolo-cation techniques to find the geographical location of YouTubeservers. A unique aspect of our work is that we perform ouranalysis on groups of related YouTube flows. This enables us toinfer key aspects of the system design that would be difficultto glean by considering individual flows in isolation. Our resultsreveal that while the RTT between users and data centers plays arole in the video server selection process, a variety of other factorsmay influence this selection including load-balancing, diurnaleffects, variations across DNS servers within a network, limitedavailability of rarely accessed video, and the need to alleviatehot-spots that may arise due to popular video content
Climate Change Impact Assessment on Han River Long Term Runoff in South Korea Based on RCP Climate Change Scenario
The 2007 World Economic Forum (WEF) referred to climate change as the overriding problem we face. Concerns have been raised about how global warming would accelerate future climate change and its consequences. Many climate change studies expect the possible occurrence of extreme high temperature, increase in heavy rains and strong typhoons in the near future. Currently, climate change scenarios are used to prepare an appropriate plan for these phenomena under climate change. The main purpose of this paper is to suggest and evaluate an operational method of assessing the potential impact of climate change on hydrologic components and water resources at the regional scale. Future runoff was simulated using high resolution Regional Circulation Model (RCM) (12.5 × 12.5 km) Representative Concentration Pathway (RCP) scenario operated by the Korea Meteorological Administration (KMA) and a semi-distribution model or SLURP (Semi-distributed Land Use-based Runoff Process). The study was carried out on the Han River including its nine dams. The study found that runoff characteristics, especially annual distribution, could change. The discharge in July tends to decrease while runoff can increase in August and September. The flow duration curve was estimated and compared with observed data and simulated daily runoff data for Paldang-dam to evaluate the effect of climate change. The analysis of the flow duration curve shows that the mean average low flow increased while the average wet and normal flow decreased under the climate change scenario
Experimental observation of hidden Berry curvature in inversion-symmetric bulk 2H-WSe2
We investigate the hidden Berry curvature in bulk 2H-WSe2 by utilizing the
surface sensitivity of angle resolved photoemission (ARPES). The symmetry in
the electronic structure of transition metal dichalcogenides is used to
uniquely determine the local orbital angular momentum (OAM) contribution to the
circular dichroism (CD) in ARPES. The extracted CD signals for the K and K'
valleys are almost identical but their signs, which should be determined by the
valley index, are opposite. In addition, the sign is found to be the same for
the two spin-split bands, indicating that it is independent of spin state.
These observed CD behaviors are what are expected from Berry curvature of a
monolayer of WSe2. In order to see if CD-ARPES is indeed representative of
hidden Berry curvature within a layer, we use tight binding analysis as well as
density functional calculation to calculate the Berry curvature and local OAM
of a monolayer WSe2. We find that measured CD-ARPES is approximately
proportional to the calculated Berry curvature as well as local OAM, further
supporting our interpretation.Comment: 6 pages, 3 figure
Optical biochemical sensor based on half-circled microdisk laser diode
In this study, a half-circled cavity based microdisk laser diode is proposed and demonstrated experimentally for an integrated photonic biochemical sensor. Conventional microdisk sensors have limitations in optical coupling and reproducibility. In order to overcome these drawbacks, we design a novel half-circled micro disk laser (HC-MDL) which is easy to manufacture and has optical output directionality. The Q-factor of the fabricated HC-MDL was measured as 7.72 × 106 using the self-heterodyne method and the side mode suppression ratio was measured as 23 dB. Moreover, gas sensing experiments were performed using the HC-MDL sensor. A wavelength shift response of 14.21 pm was obtained for 100 ppb dimethyl methylphosphonate (DMMP) gas and that of 14.70 pm was obtained for 1 ppm ethanol gas. These results indicate the possibility of highly sensitive gas detection at ppb levels using HC-MDL. This attractive feature of the HC-MDL sensor is believed to be very useful for a wide variety of optical biochemical sensor applications. © 2017 Optical Society of America.1
phonon anomaly driven by Fermi surface instability at intermediate temperature in YBaCuO
We performed temperature- and doping-dependent high-resolution Raman
spectroscopy experiments on YBaCuO to study
phonons. The temperature dependence of the real part of the phonon self-energy
shows a distinct kink at above due to softening,
in addition to the one due to the onset of the superconductivity. is clearly different from the pseudogap temperature with a maximum in the
underdoped region. The region between and
resembles that of superconducting fluctuation or charge density wave order.
While the true origin of the phonon softening is not known, we
can attribute it to a gap on the Fermi surface due to an electronic order. Our
results may reveal the role of the phonon not only in the
superconducting state but also in the intertwined orders in multilayer copper
oxide high- superconductors.Comment: 5 pages, 4 figure
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