Quality of Experience of Web-based Adaptive HTTP Streaming Clients in Real-World Environments using Crowdsourcing

2014 ◽  
Author(s):  
Benjamin Rainer ◽  
Christian Timmerer
Keyword(s):  
Real World ◽  
Quality Of Experience ◽  
Web Based ◽  
Adaptive Http Streaming ◽  
Http Streaming

Adaptive HTTP Streaming with Temporal Scalability in High Efficiency Video Coding (HEVC)

2014 ◽  
Vol 08 (02) ◽  
pp. 229-243
Author(s):  
Sachin Deshpande
Keyword(s):  
Video Coding ◽  
High Efficiency ◽  
Switching Behavior ◽  
High Efficiency Video Coding ◽  
Temporal Scalability ◽  
Server Side ◽  
Adaptive Http Streaming ◽  
Streaming Algorithm ◽  
Http Streaming

The newly approved High Efficiency Video Coding Standard (HEVC) includes temporal sub-layering feature, which provides temporal scalability. Two types of pictures — Temporal Sub-layer Access Pictures and Step-wise Temporal Sub-layer Access Pictures are provided for this purpose. This paper utilizes the temporal scalability in HEVC to provide bandwidth adaptive HTTP streaming. We describe our HTTP streaming algorithm, which is media timeline aware and which dynamically switches temporal sub-layers on the server side. We performed subjective tests to determine user perception regarding acceptable frame rates when using temporal scalability of HEVC. These results are used to control the algorithm's temporal switching behavior to provide a good quality of experience to the user. We applied Internet and 3GPP error-delay patterns to validate the performance of our algorithm.

scholarly journals Mapping and Modeling of Discussions Related to Gastrointestinal Discomfort in French-Speaking Online Forums: Results of a 15-Year Retrospective Infodemiology Study

10.2196/17247 ◽  
2020 ◽  
Vol 22 (11) ◽  
pp. e17247
Author(s):  
Florent Schäfer ◽  
Carole Faviez ◽  
Paméla Voillot ◽  
Pierre Foulquié ◽  
Matthieu Najm ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Social Media ◽  
Abdominal Pain ◽  
Real World ◽  
Syntactic Analysis ◽  
Support Vector ◽  
Online Forums ◽  
Web Based ◽  
French Speaking

Background Gastrointestinal (GI) discomfort is prevalent and known to be associated with impaired quality of life. Real-world information on factors of GI discomfort and solutions used by people is, however, limited. Social media, including online forums, have been considered a new source of information to examine the health of populations in real-life settings. Objective The aims of this retrospective infodemiology study are to identify discussion topics, characterize users, and identify perceived determinants of GI discomfort in web-based messages posted by users of French social media. Methods Messages related to GI discomfort posted between January 2003 and August 2018 were extracted from 14 French-speaking general and specialized publicly available online forums. Extracted messages were cleaned and deidentified. Relevant medical concepts were determined on the basis of the Medical Dictionary for Regulatory Activities and vernacular terms. The identification of discussion topics was carried out by using a correlated topic model on the basis of the latent Dirichlet allocation. A nonsupervised clustering algorithm was applied to cluster forum users according to the reported symptoms of GI discomfort, discussion topics, and activity on online forums. Users’ age and gender were determined by linear regression and application of a support vector machine, respectively, to characterize the identified clusters according to demographic parameters. Perceived factors of GI discomfort were classified by a combined method on the basis of syntactic analysis to identify messages with causality terms and a second topic modeling in a relevant segment of phrases. Results A total of 198,866 messages associated with GI discomfort were included in the analysis corpus after extraction and cleaning. These messages were posted by 36,989 separate web users, most of them being women younger than 40 years. Everyday life, diet, digestion, abdominal pain, impact on the quality of life, and tips to manage stress were among the most discussed topics. Segmentation of users identified 5 clusters corresponding to chronic and acute GI concerns. Diet topic was associated with each cluster, and stress was strongly associated with abdominal pain. Psychological factors, food, and allergens were perceived as the main causes of GI discomfort by web users. Conclusions GI discomfort is actively discussed by web users. This study reveals a complex relationship between food, stress, and GI discomfort. Our approach has shown that identifying web-based discussion topics associated with GI discomfort and its perceived factors is feasible and can serve as a complementary source of real-world evidence for caregivers.

A Method for Detecting Noise, Single Pass, Cross Pass and Echo of Mobile Phone

2012 ◽  
Vol 239-240 ◽  
pp. 415-421
Author(s):  
Lei Chen ◽  
Ping Wang ◽  
Fu Qiang Liu ◽  
Qing Ai ◽  
Hui Fang Pang ◽  
...  
Keyword(s):  
Mobile Phone ◽  
Real World ◽  
Quality Of Experience ◽  
Original Signal ◽  
Single Pass ◽  
Important Index ◽  
Temporal Masking ◽  
Wireless Environments ◽  
Cosine Distance

Quality of Experience is referred to as an important index for measuring how well the user's requirements are satisfied, and many methods have been presented to evaluate speech quality. But they cannot identify the kind of disturbances when the quality of speech is not good. This paper aims at proposing a method which can identify the kind of disturbances lowering the Quality of Experience. The approach proposed is based on PESQ and P563 algorithms. It adopted asymmetrical factor of PESQ and cosine distance in frequency domain to compare original signal with degraded signal. And a new time realignment method and temporal masking method were used to improve detection precision in wireless environments. This new algorithm is tested in real world including GSM and UMTS environments. The results indicate that this algorithm is helpful for detecting noise, single pass, cross pass and echoing automatically.

scholarly journals Iterative Learning for K-Approval Votes in Crowdsourcing Systems

2021 ◽  
Vol 11 (2) ◽  
pp. 630
Author(s):  
Joonyoung Kim  ◽  
Donghyeon Lee ◽  
Kyomin Jung
Keyword(s):  
Real World ◽  
Correct Answer ◽  
Iterative Learning ◽  
Wisdom Of Crowds ◽  
Approval Voting ◽  
Web Based ◽  
Mixed Case ◽  
Average Performance ◽  
Human Powered

Crowdsourcing systems have emerged as cornerstones to collect large amounts of qualified data in various human-powered problems with a relatively low budget. In eliciting the wisdom of crowds, many web-based crowdsourcing platforms have encouraged workers to select top-K alternatives rather than just one choice, which is called “K-approval voting”. This kind of setting has the advantage of inducing workers to make fewer mistakes when they respond to target tasks. However, there is not much work on inferring the correct answer from crowd-sourced data via a K-approval voting. In this paper, we propose a novel and efficient iterative algorithm to infer correct answers for a K-approval voting, which can be directly applied to real-world crowdsourcing systems. We analyze the average performance of our algorithm, and prove the theoretical error bound that decays exponentially in terms of the quality of workers and the number of queries. Through extensive experiments including the mixed case with various types of tasks, we show that our algorithm outperforms Expectation and Maximization (EM) and existing baseline algorithms.

Modeling of quality of experience for web-based unified communications with perceptual dimensions

2021 ◽  
Author(s):  
Jasmina Baraković Husić ◽  
Sabina Baraković ◽  
Ondrej Krejcar ◽  
Petra Maresova
Keyword(s):  
Quality Of Experience ◽  
Web Based ◽  
Unified Communications

scholarly journals Mapping and Modeling of Discussions Related to Gastrointestinal Discomfort in French-Speaking Online Forums: Results of a 15-Year Retrospective Infodemiology Study (Preprint)

2019 ◽  
Author(s):  
Florent Schäfer ◽  
Carole Faviez ◽  
Paméla Voillot ◽  
Pierre Foulquié ◽  
Matthieu Najm ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Social Media ◽  
Abdominal Pain ◽  
Real World ◽  
Syntactic Analysis ◽  
Support Vector ◽  
Online Forums ◽  
Web Based ◽  
French Speaking

BACKGROUND Gastrointestinal (GI) discomfort is prevalent and known to be associated with impaired quality of life. Real-world information on factors of GI discomfort and solutions used by people is, however, limited. Social media, including online forums, have been considered a new source of information to examine the health of populations in real-life settings. OBJECTIVE The aims of this retrospective infodemiology study are to identify discussion topics, characterize users, and identify perceived determinants of GI discomfort in web-based messages posted by users of French social media. METHODS Messages related to GI discomfort posted between January 2003 and August 2018 were extracted from 14 French-speaking general and specialized publicly available online forums. Extracted messages were cleaned and deidentified. Relevant medical concepts were determined on the basis of the Medical Dictionary for Regulatory Activities and vernacular terms. The identification of discussion topics was carried out by using a correlated topic model on the basis of the latent Dirichlet allocation. A nonsupervised clustering algorithm was applied to cluster forum users according to the reported symptoms of GI discomfort, discussion topics, and activity on online forums. Users’ age and gender were determined by linear regression and application of a support vector machine, respectively, to characterize the identified clusters according to demographic parameters. Perceived factors of GI discomfort were classified by a combined method on the basis of syntactic analysis to identify messages with causality terms and a second topic modeling in a relevant segment of phrases. RESULTS A total of 198,866 messages associated with GI discomfort were included in the analysis corpus after extraction and cleaning. These messages were posted by 36,989 separate web users, most of them being women younger than 40 years. Everyday life, diet, digestion, abdominal pain, impact on the quality of life, and tips to manage stress were among the most discussed topics. Segmentation of users identified 5 clusters corresponding to chronic and acute GI concerns. Diet topic was associated with each cluster, and stress was strongly associated with abdominal pain. Psychological factors, food, and allergens were perceived as the main causes of GI discomfort by web users. CONCLUSIONS GI discomfort is actively discussed by web users. This study reveals a complex relationship between food, stress, and GI discomfort. Our approach has shown that identifying web-based discussion topics associated with GI discomfort and its perceived factors is feasible and can serve as a complementary source of real-world evidence for caregivers.

EXPLORING HEALTHCARE ARCHITECTURE THROUGH THE MEDIUM OF FILM: Motives and Techniques

2014 ◽  
Vol 8 (1) ◽  
pp. 29
Author(s):  
Stephen Verderber
Keyword(s):  
Real World ◽  
The Real ◽  
Healthcare Settings ◽  
Interdisciplinary Field ◽  
Body Of Knowledge ◽  
Behavior Setting ◽  
Physical Environments ◽  
Scant Attention ◽  
History Of

The interdisciplinary field of person-environment relations has, from its origins, addressed the transactional relationship between human behavior and the built environment. This body of knowledge has been based upon qualitative and quantitative assessment of phenomena in the “real world.” This knowledge base has been instrumental in advancing the quality of real, physical environments globally at various scales of inquiry and with myriad user/client constituencies. By contrast, scant attention has been devoted to using simulation as a means to examine and represent person-environment transactions and how what is learned can be applied. The present discussion posits that press-competency theory, with related aspects drawn from functionalist-evolutionary theory, can together function to help us learn of how the medium of film can yield further insights to person-environment (P-E) transactions in the real world. Sampling, combined with extemporary behavior setting analysis, provide the basis for this analysis of healthcare settings as expressed throughout the history of cinema. This method can be of significant aid in examining P-E transactions across diverse historical periods, building types and places, healthcare and otherwise, otherwise logistically, geographically, or temporally unattainable in real time and space.

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