• 제목/요약/키워드: Quality Adaptation

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Buffer-Based Adaptive Bitrate Algorithm for Streaming over HTTP

  • Rahman, Waqas ur;Chung, Kwangsue
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제9권11호
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    • pp.4585-4603
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    • 2015
  • Video streaming services make up a large proportion of Internet traffic on both fixed and mobile access throughout the world. Adaptive streaming allows for dynamical adaptation of the bitrate with varying network conditions, to guarantee the best user experience. Adaptive bitrate algorithms face a significant challenge in correctly estimating the throughput as it varies widely over time. In this paper, we first evaluate the throughput estimation techniques and show that the method that we have used offers stable response to throughput fluctuations while maintaining a stable playback buffer. Then, we propose an adaptive bitrate scheme that intelligently selects the video bitrates based on the estimated throughput and buffer occupancy. We show that the proposed scheme improves viewing experience by achieving a high video rate without taking unnecessary risks and by minimizing the frequency of changes in the video quality. Furthermore, we show that it offers a stable response to short-term fluctuations and responds swiftly to large fluctuations. We evaluate our algorithm for both constant bitrate (CBR) and variable bitrate (VBR) video content by taking into account the segment sizes and show that it significantly improves the quality of video streaming.

The Influence of Job Stress, Self-Esteem, and Resilience on the Field Adaptation in Newly Graduated Nurses (신규간호사의 직무 스트레스, 자아존중감, 회복탄력성이 현장적응에 미치는 영향)

  • Son, Joung Eun;Kim, Sang Hee
    • Journal of Korean Clinical Nursing Research
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    • 제25권2호
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    • pp.151-160
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    • 2019
  • Purpose: This study aims to determine the relation among job stress, self-esteem, resilience, and field adaptation of the newly graduated nurses, through which an effective mediation strategy toward field adaptation and basic data on improving nursing quality can be established. Methods: The subjects were 110 newly graduated nurses who have worked at a tertiary hospital and a general hospital for less than 12 months. The data were collected, using self-reported questionnaires, from July 9 to July 31, 2018, and were analyzed by descriptive statistics, t-test, one-way ANOVA, $Scheff{\acute{e}}$ test, Pearson's correlation coefficient and stepwise multiple regression using an SPSS/WIN 24.0 program. Results: The study result showed that the newly graduated nurses' job stress, resilience, job satisfaction, and desired department influenced their field adaptation, explaining 60.2% of the variance in the field adaptation (F=42.14, p<.001). The nurses' job stress had the biggest influence on their field adaptation, explaining 38.7% of the variance. Conclusion: Human resource management strategy considering those influencing factors may improve the filed adaptation of newly graduated nurses and help them to retain in their work field.

Semi-Dynamic Digital Video Adaptation System for Mobile Environment (모바일 환경을 위한 준-동적 디지털 비디오 어댑테이션 시스템)

  • 추진호;이상민;낭종호
    • Journal of KIISE:Software and Applications
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    • 제31권10호
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    • pp.1320-1331
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    • 2004
  • A video adaptation system translates the source video stream into appropriate video stream while satisfying the network and client constraints and maximizing the video quality as much as possible. This paper proposes a semi-dynamic video adaptation scheme, in which several intermediate video streams and the information for the measuring of video quality are generated statically. The intermediate video streams are generated by reducing the resolution of the video stream by a power of two several times, and they are stored as the intermediate video streams on the video server. The statically generated information for the input video stream consists of the degrees of smoothness for each frame rate and the degree of frame definition for each pixel bit rate. It helps to dynamically generate the target video stream according to the client's QoS at run-time as quickly as possible. Experimental result shows that the proposed adaptation scheme can generate the target video stream about thirty times faster while keeping the quality degradation as less than 2% comparing to the target video stream that is totally dynamically generated, although the extra storages for the intermediate video streams are required.

Tree Coding of Speech Signals (음성신호에 대한 트리 코우딩)

  • 김경수;이상욱
    • Proceedings of the Korean Institute of Communication Sciences Conference
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    • 한국통신학회 1984년도 춘계학술발표회논문집
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    • pp.18-21
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    • 1984
  • In this paper, the tree coding using the (M, L) multi-path search algorithm has teen investigated. A hybrid adaptation scheme which employs a block adaptation as well as a sequential dadptation is described for application in quantization and compression of speech signals. Simulation results with the gybrid adaptation scheme indicate that a relatively good speech quality can be obtained at rate about 8Kbps. All necessary parameters such as MlL and filter-order were found from simulation and these parameters turned out to be a good compromise between the complexity and overall performance.

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A Metadata-enabled Approach for Scalable Video Streaming in Heterogeneous Networks

  • Thang, Truong Cong;Le, Hung T.;Nguyen, Duc V.;Pham, Anh T.
    • Journal of Multimedia Information System
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    • 제2권1호
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    • pp.153-162
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    • 2015
  • In today's pervasive computing environments, multimedia content should be adapted to meet various conditions of network connections, terminals, and user characteristics. Scalable Video Coding (SVC) is a key solution for video communication over heterogeneous networks, where user terminals have different capabilities. This paper presents a standard-compliant approach that adapts an SVC bitstream to support multiple users. The adaptation problem is formulated as an optimization problem, focusing on the tradeoff between qualities of different spatial layers of an SVC video. Then the adaptation process is represented by standard metadata of MPEG-21, which can be solved by universal processing to enable interoperable and automatic operation. Our approach provides the users with optimal quality, a wide flexibility, and seamless adaptation. To the best of our knowledge, this is the first study that shows the adaptation tradeoff between spatial layers of a conforming SVC bitstream.

Mediating Effect of Grit in the Relationship between Resilience and University Life Adaptation of College Students Majoring in Beauty after COVID-19 (코로나19(COVID-19) 이후 뷰티학과 전문대 학생들의 회복탄력성과 대학생활적응의 관계에서 그릿(Grit)의 매개 효과)

  • Min-Hee Kim;Na-Yeon Kim
    • Fashion & Textile Research Journal
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    • 제24권6호
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    • pp.789-800
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    • 2022
  • This study investigates the effect of recovery elasticity of beauty college students on university life adaptation during COVID-19. Further, the mediating effect of grit in relation to recovery elasticity and university life adaptation is analyzed. Survey data of 223 students (female: 192; male: 31) were collected for multiple and intermediate regression analyses using SPSS 24.0. The results reveal a static correlation between the lower factors of resilience, glittery, and adaptation to college life and that the resilience of junior college students in the beauty department had a static effect on grit and their adaptation to college life. Passion, a subordinate factor of grit, is mediated by the effect of grit on the relationship between resilience and adaptation to university life. However, perseverance, another subordinate factor of grit, did not have any such mediating effect. These results confirm the importance of grit, particularly passion, for resilience and adaptation to college life. It was confirmed that resilience was due to college life adaptation of beauty department students, and it was confirmed that passion, a sub-factor of grit, also had a mediating effect. Therefore, it is judged that resilience induces physical and mental adaptation, interpersonal adaptation, and academic adaptation necessary for college life, and works in many ways to improve the quality of life of beauty department junior college students. Instructors should consider developing educational programs for improving recovery elasticity and grit to help students better adapt to university life.

The Effect of Family Resilience, Social Support and Death Recognition on Quality of Death on the Adaptation of Bereavement Family (사별가족의 가족 탄력성, 사회적지지, 죽음인식, 죽음의 질이 사별 적응에 미치는 영향)

  • Heo, Hyeon-Jeom;Kwon, Young-Chae
    • Journal of Digital Convergence
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    • 제17권12호
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    • pp.271-280
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    • 2019
  • The purpose of this study was to examine how resilience, social support, perception of death and quality of death affect the bereavement adaptation. Data collection was collected from 2 April to 30 May 2018 by distributing self-reporting questionnaires to 236 people using the eyeball presentation method to those who experienced family history in B city and K area Data were analyzed with descriptive statistics and, t-test, ANOVA, and Pearson's correlations that used SPSS WIN 22.0 program and the analysis of control effect was made by using Hierarchical Multiple Regression Analysis. The result of degree of adaptation of the subject was 3.5, family resilience was 3.8 and 3.9 in the lower part. Social support was not significant. But family resilience, belief system, death perception and quality of death influenced bereavement. Based on the results of this study, it is necessary to bulid a social support network for bereavement families, to prepare for death, and to develop and program a systematic program for well-being to become a beautiful and dignified death.

Effect of Intervention Programs for Improving Maternal Adaptation in Korea: Systematic Review (국내 모성적응증진 프로그램의 효과에 대한 체계적 문헌고찰)

  • Song, Ju Eun;Ahn, Jeong Ah
    • Women's Health Nursing
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    • 제19권3호
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    • pp.129-141
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    • 2013
  • Purpose: The purpose of this study was to determine the current state of nursing intervention for maternal adaptation and its' effectiveness in Korea by utilizing a systematic review. Methods: The PICO(Population-Intervention-Compar ator-Outcome) strategy was established, and 1,720 pieces of literature published during the last ten-year period from four electronic databases were reviewed. Eighteen references that met inclusion and exclusion criteria were finally selected for systematic review. The quality of references using critical appraisal checklist for experimental studies were evaluated, and then systematic review and meta-analysis were conducted. Results: All 18 references were quasi-experimental research design. Most interventions were provided at the hospital and postpartum care center. Maternal adaptation interventions appeared to be of many types, and particularly maternal role education programs were the most common. Confidence in maternal role was used as the most common variable for the maternal adaptati on. Various interventions for helping maternal adaptation in the postnatal period improved maternal confidence, moth er-infant attachment, maternal satisfaction and mother-infant interaction effectively. Conclusion: A diversity of nursin g interventions in postnatal period improved various aspects of maternal adaptation. Randomized controlled trials and longitudinal studies are needed in order to verify the effect of interventions for maternal adaptation more clearly.

A study on adaptation measures to climate crisis for water supply system of Jeju Special Self-Governing Province (제주특별자치도 상수도 기후위기 적응대책 연구)

  • Jinkeun Kim
    • Journal of Korean Society of Water and Wastewater
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    • 제37권6호
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    • pp.447-456
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    • 2023
  • Risk assessment on Jeju Special Self-Governing Province(JSSGP)'s water supply facilities and establishment of adaptation measures for climate crisis factors were implemented. JSSGP's vulnerability to the climate crisis was high in the order of drought, heat wave, heavy rain and strong wind. As a drought adaptation measure, policies of water saving and revenue water ratio improvement were considered. As for the heat wave adaptation measure, the introduction of an advanced water treatment process was suggested in response to the increase of algae cell number which resulting in taste and odor problem. As for heavy rain adaptation measures, the installation and operation of automatic coagulant injection devices for water purification plants that take turbid surface water were proposed. As a measure to adapt to strong winds, stabilization of power supply such as installation of dual power line was proposed in preparation for power outages. It is expected that water facilities will be able to supply high-quality tap water to customers even under extreme climate conditions without interruption through risk assessment for climate crisis factors and active implementation of adaptation measures.

Machine Learning-based Estimation of the Concentration of Fine Particulate Matter Using Domain Adaptation Method (Domain Adaptation 방법을 이용한 기계학습 기반의 미세먼지 농도 예측)

  • Kang, Tae-Cheon;Kang, Hang-Bong
    • Journal of Korea Multimedia Society
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    • 제20권8호
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    • pp.1208-1215
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    • 2017
  • Recently, people's attention and worries about fine particulate matter have been increasing. Due to the construction and maintenance costs, there are insufficient air quality monitoring stations. As a result, people have limited information about the concentration of fine particulate matter, depending on the location. Studies have been undertaken to estimate the fine particle concentrations in areas without a measurement station. Yet there are limitations in that the estimate cannot take account of other factors that affect the concentration of fine particle. In order to solve these problems, we propose a framework for estimating the concentration of fine particulate matter of a specific area using meteorological data and traffic data. Since there are more grids without a monitor station than grids with a monitor station, we used a domain adversarial neural network based on the domain adaptation method. The features extracted from meteorological data and traffic data are learned in the network, and the air quality index of the corresponding area is then predicted by the generated model. Experimental results demonstrate that the proposed method performs better as the number of source data increases than the method using conditional random fields.