University of Texas at Austin

About: University of Texas at Austin is a education organization based out in Austin, Texas, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 94352 authors who have published 206297 publications receiving 9070052 citations. The organization is also known as: UT-Austin & UT Austin.

Adaptive resource allocation in multiuser OFDM systems with proportional rate constraints

Abstract: Multiuser orthogonal frequency division multiplexing (MU-OFDM) is a promising technique for achieving high downlink capacities in future cellular and wireless local area network (LAN) systems. The sum capacity of MU-OFDM is maximized when each subchannel is assigned to the user with the best channel-to-noise ratio for that subchannel, with power subsequently distributed by water-filling. However, fairness among the users cannot generally be achieved with such a scheme. In this paper, a set of proportional fairness constraints is imposed to assure that each user can achieve a required data rate, as in a system with quality of service guarantees. Since the optimal solution to the constrained fairness problem is extremely computationally complex to obtain, a low-complexity suboptimal algorithm that separates subchannel allocation and power allocation is proposed. In the proposed algorithm, subchannel allocation is first performed by assuming an equal power distribution. An optimal power allocation algorithm then maximizes the sum capacity while maintaining proportional fairness. The proposed algorithm is shown to achieve about 95% of the optimal capacity in a two-user system, while reducing the complexity from exponential to linear in the number of subchannels. It is also shown that with the proposed resource allocation algorithm, the sum capacity is distributed more fairly and flexibly among users than the sum capacity maximization method.

Personality as traits.

Abstract: 2. Please take a look at the personality traits in the right column and tick the traits that describe you. □ Dependable □ Well-organized □ Responsible □ Good selfcontrol □ High achiever □ Cautious □ Spoilt □ Objective □ Demanding □ Conscientious □ Independent □ Self-confident □ Reliable □ High achiever □ Serious □ Supporter of law and order □ Humorous □ A perfectionist □ Patient □ Disorganized □ Introvert □ Dependent □ Diligent □ Irresponsible □ Spoilt □ Impatient □ Uncomplicated □ Outgoing □ Creative □ A negotiator □ Shy and quiet □ Calm □ Even-tempered □ Competitive □ Easygoing □ Friendly □ A peace-maker □ A people-pleaser □ A great listener □ Responsible □ Bossy □ Intimidating □ Competent □ Studious □ Extrovert □ Messy □ Amiable □ Picky 3. Are there any other personality traits you have but cannot find on the list above? Please write them in the right column.

Video Quality Assessment Based on Structural Distortion Measurement

Abstract: Objective image and video quality measures play important roles in a variety of image and video pro- cessing applications, such as compression, communication, printing, analysis, registration, restoration, enhancement and watermarking. Most proposed quality assessment ap- proaches in the literature are error sensitivity-based meth- ods. In this paper, we follow a new philosophy in designing image and video quality metrics, which uses structural dis- tortion as an estimate of perceived visual distortion. A com- putationally ecient approach is developed for full-reference (FR) video quality assessment. The algorithm is tested on the video quality experts group (VQEG) Phase I FR-TV test data set. Keywords—Image quality assessment, video quality assess- ment, human visual system, error sensitivity, structural dis- tortion, video quality experts group (VQEG)

Preventing the return of fear in humans using reconsolidation update mechanisms

Abstract: Recent research on changing fears has examined targeting reconsolidation. During reconsolidation, stored information is rendered labile after being retrieved. Pharmacological manipulations at this stage result in an inability to retrieve the memories at later times, suggesting that they are erased or persistently inhibited. Unfortunately, the use of these pharmacological manipulations in humans can be problematic. Here we introduce a non-invasive technique to target the reconsolidation of fear memories in humans. We provide evidence that old fear memories can be updated with non-fearful information provided during the reconsolidation window. As a consequence, fear responses are no longer expressed, an effect that lasted at least a year and was selective only to reactivated memories without affecting others. These findings demonstrate the adaptive role of reconsolidation as a window of opportunity to rewrite emotional memories, and suggest a non-invasive technique that can be used safely in humans to prevent the return of fear. Learning about potential dangers in the environment is critical for adaptive function, but at times fear learning can be maladaptive, resulting in excessive fear and anxiety. Research on changing fears has highlighted several techniques, most of which rely on the inhibition of the learned fear response. An inherent problem with these inhibition techniques is that the fear may return, for example with stress 1 . Recent research on changing fears targeting the reconsolidation process overcomes this challenge to some extent. During reconsolidation,storedinformationisrenderedlabileafterbeingretrieved, andpharmacological manipulationsatthisstageresultinaninability to retrieve the memories at later times, suggesting that they are either erased or persistently inhibited 2–6 . Although these pharmacological manipulations are potentially useful for changing learned fears, their use in humans can be problematic. Here we show that invasive techniques are not necessary to alter fear by targeting reconsolidation. This is based on the premise that reconsolidation is an adaptive update mechanism by which new information is incorporated into old memories 3,7,8 .By introducing newinformation during the reconsolidation period, it may be possible to permanently change the fear memory. In the present study, we provide evidence in humans that old fear memories can be updated with non-fearful information provided during the reconsolidation window. As a consequence, fear responses are no longer expressed. Furthermore, this effect is specific tothe targeted fear memory, and not others, and persists forat least a year.Thesefindingsdemonstratetheadaptiveroleofreconsolidation as a window of opportunity to rewrite emotional memories, and suggest a non-invasive technique that can be used safely and flexibly in humans to prevent the return of fear.

Image Quality Assessment: From Error Measurement to Structural Similarity

Abstract: Objective methods for assessing perceptual im- age quality traditionally attempt to quantify the visibility of errors (dierences) between a distorted image and a ref- erence image using a variety of known properties of the hu- man visual system. Under the assumption that human visual perception is highly adapted for extracting structural information from a scene, we introduce an alternative com- plementary framework for quality assessment based on the degradation of structural information. As a specific exam- ple of this concept, we develop a Structural Similarity Index and demonstrate its promise through a set of intuitive ex- amples, as well as comparison to both subjective ratings and state-of-the-art objective methods on a database of images compressed with JPEG and JPEG2000. A MatLab imple- mentation of the proposed algorithm is available online at http://www.cns.nyu.edu/~lcv/ssim/.