• Journal of the Korean Data and Information Science Society
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• v.22 no.5
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• pp.989-998
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• 2011

Cloud computing provides computation, software, data access, and storage services that do not require end-user knowledge of the physical location and configuration of the system that delivers the services. Cloud computing providers have setup several data centers at different geographical locations over the Internet in order to optimally serve needs of their customers around the world. One of the fundamental challenges in geographically distributed clouds is to provide efficient algorithms for supporting inter-cloud data management and dissemination. In this paper, we propose a group quorum system (GQS)-based dissemination for improving the interoperability of inter-cloud in time-critical event dissemination service, such as computing policy updating, message sharing, event notification and so forth. The proposed GQS-based method organizes these distributed clouds into a group quorum ring overlay to support a constant event dissemination latency. Our numerical results show that the GQS-based method improves the efficiency as compared with Chord-based and Plume methods.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.431-435
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• 2005

Mobile Ad-Hoc network is the network(MANET) of mobile nodes which has no fixed infrastructure, and mobile node in MANET can move and communicate freely each other. Recently, many researches for mobility management of mobile nodes are actively carried out by using the location information of mobile nodes. The location management is an important issue in MANET because location information of mobile node is frequently changed in MANET. In this paper, an adaptive mobility management scheme using fuzzy-logic based GQS by considering the mobile locality is proposed in order to manage location information of mobile nodes in MANET efficiently. The proposed scheme selects mobility databases adaptively from GQS by considering the locality of mobile node. The performance of the mobility management scheme proposed in this paper is evaluated by an analytic model and compared with that of existing UQS based mobility management scheme.

• Restorative Dentistry and Endodontics
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• v.46 no.1
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• pp.8.1-8.7
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• 2021

Objectives: The reliability and educational quality of videos on YouTube for patients seeking information regarding instrument separation in root canal treatment were evaluated. Materials and Methods: YouTube was searched for videos on instrument separation in root canal treatment. Video content was scored based on reliability in terms of 3 categories (etiology, procedure, and prognosis) and based on video flow, quality, and educational usefulness using the Global Quality Score (GQS). Descriptive statistics were obtained and the data were analyzed using analysis of variance and the Kruskal-Wallis test. Results: The highest mean completeness scores were obtained for videos published by dentists or specialists (1.48 ± 1.06). There was no statistically significant difference among sources of upload in terms of content completeness. The highest mean GQS was found for videos published by dentists or specialists (1.82 ± 0.96), although there was no statistically significant correlation between GQS and the source of upload. Conclusions: Videos on YouTube have incomplete and low-quality content for patients who are concerned about instrument separation during endodontic treatment, or who experience this complication during endodontic treatment.

• Clinics in Shoulder and Elbow
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• v.25 no.3
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• pp.217-223
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• 2022

Background: YouTube has become a popular source of healthcare information in orthopedic surgery. Although quality-based studies of YouTube content have been performed for information concerning many orthopedic pathologies, the quality and accuracy of information on the rotator cuff have yet to be evaluated. The purpose of the current study was to evaluate the reliability and educational content of YouTube videos concerning the rotator cuff. Methods: YouTube was queried for the term "rotator cuff." The first 50 videos from this search were evaluated. Video reliability was assessed using the Journal of the American Medical Association (JAMA) benchmark criteria (range, 0-5). Educational content was assessed using the global quality score (GQS; range, 0-4) and the rotator cuff-specific score (RCSS; range, 0-22). Results: The mean number of views was 317,500.7±538,585.3. The mean JAMA, GQS, and RCSS scores were 2.7±2.0, 3.7±1.0, and 5.6±3.6, respectively. Non-surgical intervention content was independently associated with a lower GQS (β=-2.19, p=0.019). Disease-specific video content (β=4.01, p=0.045) was the only independent predictor of RCSS. Conclusions: The overall quality and educational content of YouTube videos concerned with the rotator cuff were low. Physicians should caution patients in using such videos as resources for decision-making and should counsel them appropriately.

• Journal of Korea Multimedia Society
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• v.20 no.8
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• pp.1369-1378
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• 2017

Pub/Sub (Publish/Subscribe) paradigm is a simple and easy to use model for interconnecting applications in a distributed environment. In general, subscribers register their interests in a topic or a pattern of events and then asynchronously receive events matching their interest, regardless of the events' publisher. In order to build a low latency lightweight pub/sub system for Internet of Things (IoT) services, we propose a GQSFPS (Group Quorum System-based Fog Pub/Sub) system that is a core component in the event-driven service oriented architecture framework for IoT services. The GQSFPS organizes multiple installed pub/sub brokers in the fog servers into a group quorum based P2P (peer-to-peer) topology for the efficient searching and the low latency accessing of events. Therefore, the events of IoT are cached on the basis of group quorum, and the delay-sensitive IoT applications of edge devices can effectively access the cached events from group quorum fog servers in low latency. The performance of the proposed GQSFPS is evaluated through an analytical model, and is compared to the GQPS (grid quorum-based pud/sub system).

• Restorative Dentistry and Endodontics
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• v.46 no.3
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• pp.40.1-40.12
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• 2021

Objectives: The purpose of this study was to critically evaluate the quality, reliability and educational content of the information of vital pulp treatment videos available on YouTube. Materials and Methods: The keywords "pulpotomy" and "pulp capping" were searched on YouTube on 5th July 2020, until 60 English language videos of each search term with a duration shorter than 15 minutes were acquired. Video characteristics were recorded and Video Power Index (VPI) was calculated. Reliability and educational quality of videos were evaluated using the Modified DISCERN score, the Journal of American Medical Association (JAMA) benchmark criteria and Global Quality Scores (GQS). Videos were categorized by uploading source. Results: Regarding pulpotomy, 31.7% of the videos were uploaded by specialists and 68.3% were directed by non-specialists. In the case of pulp capping, the corresponding percentages were 45% and 55%, respectively. Videos uploaded by specialists had significantly higher modified DISCERN, JAMA and GQS scores compared to those uploaded by non-specialists. Endodontists tended to have the highest reliability and VPI scores. Conclusions: YouTube videos on vital pulp treatment contain low educational quality or incomplete information. Low popularity of dental pulp capping and pulpotomy videos may be attributed to the specialized nature of these procedures. As YouTube represents an important source for patient information about different health topics, reliable informative videos should be uploaded by specialized dental professionals.

• Archives of Plastic Surgery
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• v.49 no.5
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• pp.668-675
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• 2022

Background Educational resources on the internet are extensively used to obtainmedical information. YouTube is the most accessed video platform containing information to enhance the learning experience of medical professionals. This study systematically analyzed the educational value of microsurgery-related videos on this platform. Methods A systematic review was conducted on YouTube from April 18 to May 18, 2020, using the following terms: "microsurgery," "microsurgical," "microsurgical anastomosis," "free flap," and "free tissue transfer." The search was limited to the first 100 videos, and two independent reviewers screened for eligible entries and analyzed their educational value using validated scales, including a modified version of the DISCERN score (M-DISCERN), Journal of the American Medical Association (JAMAS) benchmark criteria, and the Global Quality Score (GQS). Evaluation of video popularity was also assessed with the video power index (VPI). Results Of 356 retrieved videos, 75 (21%) were considered eligible. The educational quality of videos was highly variable, and the mean global scores for the M-DISCERN, JAMAS, and GQS for our sample were consistent with medium to low quality. Conclusions A limited number of videos on YouTube for microsurgical education have high-educational quality. The majority scored low on the utilized criteria. Peer-reviewed resources seem to be a more reliable resource. Although the potential of YouTube should not be disregarded, videos should be carefully appraised before being usedas an educational resource.

• Clinics in Shoulder and Elbow
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• v.25 no.2
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• pp.145-153
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• 2022

Background: While online orthopedic resources are becoming an increasingly popular avenue for patient education, videos on YouTube are not subject to peer review. The purpose of this cross-sectional study was to evaluate the quality of YouTube videos for patient education in ulnar collateral ligament (UCL) injuries of the elbow. Methods: A search of keywords for UCL injury was conducted through the YouTube search engine. Each video was categorized by source and content. Video quality, reliability, and accuracy were assessed by two independent raters using five metrics: (1) Journal of American Medical Association (JAMA) benchmark criteria (range 0-4) for video reliability; (2) modified DISCERN score (range 1-5) for video reliability; (3) Global Quality Score (GQS; range 1-5) for video quality; (4) ulnar collateral ligament-specific score (UCL-SS; range 0-16), a novel score for comprehensiveness of health information presented; and (5) accuracy score (AS; range 1-3) for accuracy. Results: Video content was comprised predominantly of disease-specific information (52%) and surgical technique (33%). The most common video sources were physician (42%) and commercial (23%). The mean JAMA score, modified DISCERN score, GQS, UCL-SS, and AS were 1.8, 2.4, 1.9, 5.3, and 2.7 respectively. Conclusions: Overall, YouTube is not a reliable or high-quality source for patients seeking information regarding UCL injuries, especially with videos uploaded by non-physician sources. The multiplicity of low quality, low reliability, and irrelevant videos can create a cumbersome and even inaccurate learning experience for patients.

• Clinics in Shoulder and Elbow
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• v.26 no.2
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• pp.162-168
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• 2023

Background: Reverse shoulder arthroplasty (RSA) has evolved continuously over recent years, with expanded indications and better outcomes. YouTube is one of the most popular sources globally for health-related information available to patients. Evaluating the reliability of YouTube videos concerning RSA is important to ensure proper patient education. Methods: YouTube was queried for the term "reverse shoulder replacement." The first 50 videos were evaluated using three different scores: Journal of the American Medical Association (JAMA) benchmark criteria, the global quality score (GQS), and the reverse shoulder arthroplasty-specific score (RSAS). Multivariate linear regression analyses were conducted to determine the presence of a relationship between video characteristics and quality scores. Results: The average number of views was 64,645.78±264,160.9 per video, and the average number of likes was 414 per video. Mean JAMA, GQS, and RSAS scores were 2.32±0.64, 2.31±0.82, and 5.53±2.43, respectively. Academic centers uploaded the highest number of videos, and surgical techniques/approach videos was the most common video content. Videos with lecture content predicted higher JAMA scores whereas videos uploaded by industry predicted lower RSAS scores. Conclusions: Despite its massive popularity, YouTube videos provide a low quality of information on RSA. Introducing a new editorial review process or developing a new platform for patients' medical education may be necessary. Level of evidence: Not applicable.

• Journal of the Korean Data and Information Science Society
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• v.23 no.6
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• pp.1259-1269
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• 2012

Cloud computing has rapidly become a new infrastructure for organizations to reduce their capital cost in IT investment and to develop planetary-scale distributed applications. One of the fundamental challenges in geographically distributed clouds is to provide efficient algorithms for supporting inter-cloud data management and dissemination. In this paper, we propose a geographic group quorum system (GGQS)-based hybrid algorithm for improving the interoperability of inter-cloud in time-critical event dissemination service, such as computing policy updating, message sharing, event notification and so forth. The proposed algorithm first organizes these distributed clouds into a geographic group quorum overlay to support a constant event dissemination latency. Then it uses a hybrid protocol that combines geographic group-based broad-cast with quorum-based multicast. Our numerical results show that the GGQS-based hybrid algorithm improves the efficiency as compared with Chord-based, Plume an GQS-based algorithms.