• Journal of information and communication convergence engineering
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• v.14 no.4
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• pp.240-245
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• 2016

Scalable video streaming over wireless networks has many challenges. The most significant challenge is related to packet loss. To overcome this problem, in this paper, we propose an unequal loss protection (ULP) method using a new forward error correction (FEC) mechanism for robust scalable video streaming over wireless networks. For an efficient FEC assignment considering video quality, we first introduce a simple and efficient performance metric, the layer-based recovery rate (LRR), for quantifying the unequal error propagation effects of the temporal and quality layers on the basis of packet losses. LRR is based on the unequal importance in both the temporal and the quality layers of a hierarchical scalable video coding structure. Then, the proposed ULP-LRR method assigns an appropriate number of FEC packets on the basis of the LRR to protect the video layers against packet lossy network environments. Compared with conventional ULP algorithms, the proposed ULP-LRR algorithm demonstrates a higher performance for various error-prone wireless channel statuses.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.6
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• pp.1327-1332
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• 2011

In the mobile meteorological information services, an existing sensor system should be expanded to serve precise information. This is because of large cost problem to add the existing sensors. This thesis proposes a system architecture to construct scalable mobile meteorological information services and suggests mobile phone, sensor network, and public traffic vehicle as expended sensors. The proposed scalable sensors are compared each other and analysed the results to evaluated their strength and weakness. In this system, based on the characteristics of the sense data collected at server, a data processing methods are proposed to support efficient query processing. The proposing data processing methods have several benefits. They compress some data volume sensed by various sources on some area at some time to a logical unit. Still it could preserve same services quality.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.46 no.1
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• pp.94-101
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• 2009

This paper presents scalable modeling of spiral inductors for RFIC design based on $0.13{\mu}m$ RF CMOS process. For scalable modeling, several inductor patterns are designed and fabricated with variations of width, number of turns and inner radius. Feeding structures are optimized for accurate de-embedding of pad effects. After measuring the S parameters of the fabricated patterns, double-$\pi$ equivalent circuit parameters are extracted for each device and their geometrical dependences are modeled as scalable functions. The inductor library provides two types of models including standard and symmetric inductors. Standard and symmetric inductors have the range of $0.12{\sim}10.7nH$ and $0.08{\sim}13.6nH$ respectively. The models are valid up to 30GHz or self-resonance frequency. Through this research, a scalable inductor library with an error rate below 10% is developed for $0.13{\mu}m$ RF CMOS process.

• Journal of the Korea Society of Computer and Information
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• v.24 no.7
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• pp.101-108
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• 2019

In this paper, we propose a new scalable and reliable combat system software in battleship which was developed procedurally in the past. Recently, combat system software is required to change frequently due to addition of new equipment and change of function. To solve those problems, this paper propose how to change combat system software into scalable software using class structure change and design pattern. Simulation results show that our scheme provides better performances and reliability than conventional scheme. Therefore proposed scheme can be efficiently used in Naval combat system.

• Proceedings of the IEEK Conference
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• 2002.07a
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• pp.50-53
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• 2002

There are increasing needs to deliver the multimedia streaming over heterogeneous networks. When considering network environments and equipment accessed by user, delivery of video streaming must be scalable. There are many kinds of scalable video coding: spatial, temporal, SNR, and hybrid. The SNR scalable and spatial resolution, but different SNR quality with respect to layers. The 1-layer SNR scalable encoder produces SNR scalable video streams with ease. But, there is drift problem. Modified 1-layer approach does not have this problem but coding inefficiency, and is not MPEG-compliant. The present MPEG-compliant 2-layer encoder comes out to reduce coding rate. But it still use only base layer to encode whole layer. In this paper, we propose adaptive MPEG-compliant 2-layer encoder. Using linear combination algorithm, encoder use 1 motion vector to encode the sequences efficiently. By dong this, we can achieve the coding efficiency of SNR scalable coding.

• Proceedings of the Korea Information Processing Society Conference
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• 2006.05a
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• pp.929-932
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• 2006

본 논문에서는 암호화된 Scalable Video Coding (SVC) 비트스트림에서의 조건적 접근제어을 위한 키 관리 기법을 제안한다. 스케일러블 비디오 코딩 기술은 한번 인코딩 후 비트스트림 추출을 통해 다양한 확장성(scalabbility)을 가지는 비디오를 생성 할 수 있는 기술로 확장하는 단위마다 다른 키로 암호화 하여 조건적 접근제어를 구성 할 수 있다. 그러나 기존의 조건적 접근제어 기술은 암호화 시 복수의 키가 필요하며 이는 키의 관리와 분배에 어려움을 준다. 이러한 문제를 해결하기 위해 본 논문에서는 기존의 스케일러블 코딩기법에서 조건적 접근제어를 위한 키 관리기법을 살펴보고 SVC 의 확장 구조에 맞는 키 관리 기법을 제안한다. 제안한 방법은 SVC 를 이용한 스트리밍 테스트베드에서 구현되어, 조건적 접근제어를 위한 키 관리기능의 유용성을 확인하였다.

• The Transactions of the Korea Information Processing Society
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• v.6 no.11
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• pp.2922-2931
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• 1999

In this paper, we propose a new framework for scalable media object to adapt the various QoS requirements in the heterogeneous networking environment. An MPEG-2 video is split into a set of scalable media objects in terms of temporal scaling and fidelity scaling. The portion of the scalable media objects is selectively delivered to adapt the QoS requirement. This framework can satisfy the various QoS requirements on bandwidth, even though the clients share a multipoint channel. By analysis on the rate-distortion characteristics of scalable media object framework, we shows our approach is feasible to support the various QoS requirements.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.3C
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• pp.408-418
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• 2004

In this paper, we propose a novel scalable video coding algorithm based on adaptively weighted multiple reference frame method. To improve the coding efficiency in the enhancement layer, the enhancement frame is predicted by the sum of adaptively weighted double motion compensated frames in the enhancement layer and the current frame in the base layer, according to the input video characteristics. By employing adaptive reference selection scheme at the decoder, the proposed method reduce the drift problem significantly. From the experimental results, the proposed algorithm shows more than 1.0 ㏈ PSNR improvement, compared with the conventional scalable H.263+ for various packet loss rate channel conditions.

• Journal of KIISE:Computing Practices and Letters
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• v.8 no.3
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• pp.318-327
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• 2002

This paper Introduces a new scanning method for network-adaptive scalable streaming video coding methodologies such as the MPEG-4 Fine Granular Scalable (FGS) Coding. Proposed scanning method can guarantee the subjectively improved picture quality of the region of the interest in the decoded video by managing the image information of that interested region to be encoded and transmitted most-preferentially, and also to be decoded most-preferentially. Proposed scanning method can lead the FGS coding method to achieve improved picture quality, in about 1dB ~ 3dB better, especially on the region of interest.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.2
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• pp.901-923
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• 2017

Efficient key distribution and management mechanisms as well as lightweight ciphers are the main pillar for establishing secure wireless sensor networks (WSN). Several symmetric based key distribution protocols are already proposed, but most of them are not scalable, yet vulnerable to a small number of compromised nodes. In this paper, we propose an efficient and scalable key management and distribution framework, named KMMR, for large scale WSNs. The KMMR contributions are three fold. First, it performs lightweight local processes orchestrated into upward and downward tiers. Second, it limits the impact of compromised nodes to only local links. Third, KMMR performs efficient secure node addition and revocation. The security analysis shows that KMMR withstands several known attacks. We implemented KMMR using the NesC language and experimented on Telosb motes. Performance evaluation using the TOSSIM simulator shows that KMMR is scalable, provides an excellent key connectivity and allows a good resilience, yet it ensures both forward and backward secrecy. For a WSN comprising 961 sensor nodes monitoring a 60 hectares agriculture field, KMMR requires around 2.5 seconds to distribute all necessary keys, and attains a key connectivity above 96% and a resilience approaching 100%. Quantitative comparisons to earlier work show that KMMR is more efficient in terms of computational complexity, required storage space and communication overhead.