• Journal of Broadcast Engineering
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• v.21 no.2
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• pp.252-260
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• 2016

The performance of human detection system is affected by camera location and view angle. In 2D image acquired from such camera settings, humans are displayed in different sizes. Detecting all the humans with diverse sizes poses a difficulty in realizing a real-time system. However, if the size of a human in an image can be predicted, the processing time of human detection would be greatly reduced. In this paper, we propose a method that estimates human size by constructing an indoor scene in 3D space. Since the human has constant size everywhere in 3D space, it is possible to estimate accurate human size in 2D image by projecting 3D human into the image space. Experimental results validate that a human size can be predicted from the proposed method and that machine-learning based detection methods can yield the reduction of the processing time.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.3B
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• pp.526-535
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• 2010

In this paper, we propose the fault-tolerant network-based mobility management scheme for supporting multimedia services of broadcasting & communications convergence in fixed mobile convergence (FMC) networks. The proposed scheme is based on AIMS (Access Independent Mobility Service) which is developed for the mobility support among heterogeneous access networks. To support stable location management and handover control for a MN, the proposed scheme supports stable management of binding information by sensing network attachment and detachment of a mobile node (MN). In addition, the proposed fault-tolerant (FT) AIMS supports a function of message retransmission for the support of handover control message and a function of heartbeat message transmission for the support of stable access network environments to a mobile node. We evaluate and analyze the performance of the proposed scheme through the implementation of AIMS system test-bed.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.10
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• pp.1-10
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• 1998

It is important to know phase offsets of a spreading code in the code division multiple access(CDMA) mobile communication systems because different phase offsets of the same spreading code are used to distinguish each base station. When the period of the code is not that long, the relative phase offset between the code and its shifted code can be found by comparing them, but as the period of the code increases it becomes difficult to find the phase offset. This paper describes a method to calculate the phase offset of a binary code based on the number theoretical approach. We define an accumulator function which plays a central role in this paper, and relationships between the functions are clarified. This number theoretical approach and their results show that this method is very easy for the phase offset calculation. Its application to the CDMA system and circuit realization of the phase offset calculation are also discussed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39A no.11
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• pp.625-636
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• 2014

In this paper, we propose a new embedded image compression scheme which uses rate-distortion optimized block coding of wavelet coefficients. Unlike to previous works in which set-partition or block-partition is performed according to the magnitude of wavelet coefficients, the proposed scheme achieves rate-distortion optimization by sorting wavelet coefficients or blocks according to their expected rate-distortion slope. At the same time, it performs the optimized block-partition coding using the expected rate-distortion slope of blocks. The proposed scheme also uses various relationship of wavelet coefficients for the entropy coding. Experimental results demonstrate that the proposed image compression scheme provides better overall performance than the existing embedded coding schemes such as SPIHT and EBCOT, in which the PSNR gains of the proposed scheme are about 0.11~1.16dB and -0.18~0.52dB, respectively.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.10
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• pp.1183-1185
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• 2016

Low bit-rate speech coder in digital speech communications synthesizes speech using vocal tract model parameters. In this case, the spectra of the synthesized speech can be much distorted since the allocated bits for the parameters are considerably limited, which results in the degradation of speech intelligibility. In this paper, we propose a speech intelligibility improvement method using stochastic spectral equalizer. This method stochastically obtains the weight vector of each speech coder using spectral ratios between original and synthesized speech, then applies this weight vector to synthesized speech. From the experiments of objective speech intelligibility tests, we found that the performance of the proposed method is better than that of the conventional method.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.10
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• pp.1155-1166
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• 2016

In this paper, we propose a new embedded video compression scheme which uses three-dimensional rate-distortion optimization based block coder. After the proposed scheme removes temporal redundancy by applying the motion compensated temporal filtering(MCTF) on input video frames, two dimensional discrete wavelet transform is applied on video frames to remove spatial redundancy. The three-dimensional wavelet coefficients generated in this way are sorted according to their expected rate-distortion slope and encoded by using the three-dimensional block partition coding method. The proposed scheme also uses both the effective color video coding method which maintains embedded features, and the efficient bit-rate control method. Experimental results demonstrate that the proposed scheme not only produces embedded bit-streams, but also outperforms existing video compression schemes.

• The Journal of Information Technology
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• v.1 no.1
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• pp.155-172
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• 1998

Electronic commerce is more than just handling purchase transactions and funds transfers over the internet. Despite electronic commerce's past roots in transactions between large corporations, banks, and other financial institutions, the use of the internet as a way to bring electronic commerce to the individual consumer has led to a shift in viewpoint. Over the past few years, both the press and the business community have increased their focus on electronic commerce involving the consumer Electronic commerce includes the tasks that support the buying and selling of goods and services, and interactions among those tasks. Electronic commerce enables companies to close stores, reduce inventory requirements, and distribute products over the internet. Electronic commerce can simplify communication and change relationships The economics of electonic commerce is concernec with a new market whose delivery and communication infrastructure happens to be the internet. The economics of electronic commerce focuses on markets whose transactions are facilitated by communications networks and delivery systems. However, any digital communications media will soon be capable of supporting virtual transactions In the electronic marketplace, including telephone wires, cables, microwaves, and satellites. Thus, electronic commerce can offer your company both short-term and long-term befits. moving business practices, such as ordering, invoicing, and consumer support, to network-based systems can also reduce the paperwork involved in business-to-business transactions. This study conducted a study on economic effects of electronic commerce

• Journal of Broadcast Engineering
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• v.10 no.3
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• pp.313-320
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• 2005

The increasing popularity of multimedia streaming services introduces new challenges in content distribution. Especially, it is important to provide the QoS guarantees as they are increasingly expected to support the multimedia applications. Multimedia streams typically experience the high start-up delay due to the large protocol overhead, the delay, and the loss properties of the wireless networks. The service providers can improve the performance of multimedia streaming by caching the initial segment (prefix) of the popular streams at proxies near the requesting clients. The proxy can initiate transmission to the client while requesting the remainder of the stream from the server. In this paper, we propose the traffic based caching algorithm (TSLRU) to improve the performance of caching proxy. TSLRU classifies the traffic into three types, and improve the performance of caching proxy by reflecting the several elements such as traffic types, recency, frequency, object size when performing the replacement decision. In simulation, TSLRU performs better than the existing schemes in terms of byte hit rate, hit rate, startup latency, and throughput.

• Journal of Broadcast Engineering
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• v.23 no.2
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• pp.283-292
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• 2018

Devices capable of capturing and displaying high dynamic range (HDR) images with significantly increased brightness range compared to low dynamic range (LDR) images have been developed and various methods for efficiently converting the brightness range of an image have been developed. In this paper, we propose a reverse tone mapping method using a guided filter to efficiently convert LDR images into HDR images. After obtaining brightness enhancement function (BEF) using a guided filter, we can reconstruct HDR image from one LDR image. In addition, when the image is too bright or dark, the proposed method maximizes the image quality of the reconstructed HDR image by estimating and adjusting the exposure value before expanding the brightness range of images. Computer simulations show that the proposed method produces HDR images of superior quality compared with the conventional methods.

• Journal of Science of Art and Design
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• v.4
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• pp.5-25
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• 2002

It is not easy to get more attention as a prominent advertising expression among various types of numerous advertisements. Due to the voluminous expansion of advertising communications and the change of the media, new advertising creatives must be needed for serving to differentiate the message , inviting audiences to participate more positively in advertising communications This thesis aims at reviewing the absence as an advertising creative. And this thesis is about the significations of the absence. Chapter I describes the aim of this thesis about the absence as an advertising creative And Chapter II introduces the general concept, perception of the absence and its possibilities as an advertising creative And also mentions about the absence as one of paradoxical expressions with rhetorical theories as well as semiotics. Chapter III deals with the signification of the absence with introducing semiotic methods such as the theory of R. Barthes Chapter IV discusses the signification of the absence as an advertising creative talking into consideration of semiotic theories. And I categorize the types of the absence in advertising expressions. The absence is categorized into 5 types in this thesis. Type (1) is the absence of product which is supposed to be advertised, type (2) is the absence of product and make product image located out of main image of an advertising expression for introducing features of a product itself. And type (3) is the absence of the imaginary audience to invite an audience to participate more spontaneously. Type (4) is the absence of headlines, and type (5) is the absence of almost all visual images and verbal message but a corporate symbol or brand logo. The signification of S types of the absence can be described on the basic of semiotic theories, especially the theory of R. Barthes. It's my hope that this thesis about the absence as an advertising creative will serve as the basic theory for the empirical research about advertising expressions containing images of the absence.