Survey of Error Concealment techniques: Research directions and open issues

© 2015 IEEE. Error Concealment (EC) techniques use either spatial, temporal or a combination of both types of information to recover the data lost in transmitted video. In this paper, existing EC techniques are reviewed, which are divided into three categories, namely Intra-frame EC, Inter-frame EC, and Hybrid EC techniques. We first focus on the EC techniques developed for the H.264/AVC standard. The advantages and disadvantages of these EC techniques are summarized with respect to the features in H.264. Then, the EC algorithms are also analyzed. These EC algorithms have been recently adopted in the newly introduced H.265/HEVC standard. A performance comparison between the classic EC techniques developed for H.264 and H.265 is performed in terms of the average PSNR. Lastly, open issues in the EC domain are addressed for future research consideration

Frame Interpolation for Cloud-Based Mobile Video Streaming

© 2016 IEEE. Cloud-based High Definition (HD) video streaming is becoming popular day by day. On one hand, it is important for both end users and large storage servers to store their huge amount of data at different locations and servers. On the other hand, it is becoming a big challenge for network service providers to provide reliable connectivity to the network users. There have been many studies over cloud-based video streaming for Quality of Experience (QoE) for services like YouTube. Packet losses and bit errors are very common in transmission networks, which affect the user feedback over cloud-based media services. To cover up packet losses and bit errors, Error Concealment (EC) techniques are usually applied at the decoder/receiver side to estimate the lost information. This paper proposes a time-efficient and quality-oriented EC method. The proposed method considers H.265/HEVC based intra-encoded videos for the estimation of whole intra-frame loss. The main emphasis in the proposed approach is the recovery of Motion Vectors (MVs) of a lost frame in real-time. To boost-up the search process for the lost MVs, a bigger block size and searching in parallel are both considered. The simulation results clearly show that our proposed method outperforms the traditional Block Matching Algorithm (BMA) by approximately 2.5 dB and Frame Copy (FC) by up to 12 dB at a packet loss rate of 1%, 3%, and 5% with different Quantization Parameters (QPs). The computational time of the proposed approach outperforms the BMA by approximately 1788 seconds

Happy Family Kitchen II, a community-based participatory research (CBPR) to enhance Family Health, Happiness and Harmony in Hong Kong: A cluster randomized control trial under FAMILY Project

Oral Poster Presentation SessionHong Kong Council of Social Service and School of Public Health, HKU conducted a three-arm cluster randomized control trial (cRCT) of a community-based participatory research (CBPR) “Happy Family Kitchen II” during July 2012 to June 2013. The present paper compared intervention arm A and control arm C to determine whether CBPR intervention improved family health, happiness and harmony (3Hs). 31 organizations in Tsuen Wan and Kwai Tsing districts were randomly allocated into: intervention arms A (n=11) and B (n=10), and waitlist control arm C (n=10).Within positive psychology and an agreed similar framework, each organization organized their own program on one selected theme of “Five-Taste Model” for people aged 6+ recruited by organization. Arm A had two intervention-sessions and one tea-gathering, and arm C had tea-gathering first (intervention at 3 months later). Participants were assessed four times (T1, pre-intervention; T2, immediately post-intervention; T3 and T4, 1 and 3 months after T2). Changes of primary outcomes from T1 to T3/T4 were compared in participants aged 12+ of arms A and C. Behavior score change was greater in arm A (n=416) than arm C (n=432) at both T3 (Effect size=0.11, p=0.03) and T4 (ES=0.21, p=0.003). Family health score and happiness score changes were greater in arm A than arm C at T3, with ES=0.23 (p=0.001) and ES=0.18 (p=0.01) respectively. Mental health score and intention score changes were greater in arm A than arm C at T4, with ES=0.16 (p=0.03) and ES=0.18 (p=0.01) respectively. All changes above indicated improvements in outcomes. This was the first cRCT to evaluate a CBPR short intervention in Hong Kong, which was effective with small effect size in increasing participants’ intention and practice in healthy behaviors and improving family 3Hs, suggesting that CBPR, evidence-based and evidence-generating programmes are feasible and effective.postprin

A lead-free piezoelectric transformer in radial vibration modes

Author name used in this publication: D. M. LinAuthor name used in this publication: K. H. LamAuthor name used in this publication: S. WangAuthor name used in this publication: X. Z. Zhao2006-2007 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

A study on the disk-shaped piezoelectric transformer with multiple outputs

Author name used in this publication: K. H. LamAuthor name used in this publication: S. WangAuthor name used in this publication: K. W. KwokAuthor name used in this publication: X. Z. Zhao2007-2008 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Energy harvesting with piezoelectric drum transducer

Author name used in this publication: Kwok Ho LamAuthor name used in this publication: Cheng Liang SunAuthor name used in this publication: Kin Wing KwokAuthor name used in this publication: Helen Lai Wa ChanAuthor name used in this publication: Ming Sen GuoAuthor name used in this publication: Xing-Zhong Zhao2006-2007 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Lead-free multilayer piezoelectric transformer

Author name used in this publication: K. H. LamAuthor name used in this publication: S. WangAuthor name used in this publication: C. L. SunAuthor name used in this publication: X. Z. Zhao2006-2007 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

ACER eNews 01 January 2007

This paper presents a centralized control system that coordinates parallel operations of different distributed generation (DG) inverters within a microgrid. The control design for the DG inverters employs a new Model Predictive Control algorithm that allows faster computational time for large power systems by optimizing the steady-state and the transient control problems separately. An overall energy management system is also implemented for the microgrid to coordinate load sharing among different DG units during both grid-connected and islanded operations. The design concept of the proposed control system is evaluated through simulation studies under different test scenarios. The impact of the increased penetration of DG units on the distribution grid is also investigated using the proposed microgrid. The simulation results show that the operations of the DG units within the microgrid can be coordinated effectively under the proposed control system to ensure stable operation of the overall microgrid