• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.393-394
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• 2006

This paper lists various error resilience tools and analyzes performance in IP Datacast over DVB-H systems and schemes are proposed. Experiments shows that, in DVB-H environment, encoding with macroblock line intra update can achieve the best error correction ability, because this tool can make full use of spatial correlation for intra prediction and reduce the requirement of bit rate.

• Journal of Korean Library and Information Science Society
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• v.54 no.2
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• pp.1-22
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• 2023

In this study, we propose a plan to reflect LRM in various library-related standards or systems through analyzing the reflection of LRM in RDA. To this end, LRM and RDA 2020 were analyzed in terms of entities, relationships, attributes, and encoding schemes. First of all, for the mapping of entities, relationships, and attributes, all properties and relationships were extracted for each entity of RDA, LRM elements corresponding to each property and relationship were found and mapped, and encoding schemes were additionally compared. As a result, the things to consider in the standards and systems to which LRM is to be applied are: first, entities development considering the LRM hierarchy; second, new relation or shortcut path relation development; third, attributes expansion according to the entities considering the LRM hierarchical structure, and fourth, the development of various encoding scheme. Through this study, it will be possible to find an application plan using the application of RDA as a model in standards or systems to accept LRM.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.3
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• pp.1193-1209
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• 2015

Network coding is promising to maximize network throughput and improve the resilience to random network failures in various networking systems. In this paper, the problem of providing efficient confidentiality for practical network coding system against a global eavesdropper (with full eavesdropping capabilities to the network) is considered. By exploiting a novel combination between the construction technique of systematic Maximum Distance Separable (MDS) erasure coding and traditional cryptographic approach, two efficient schemes are proposed that can achieve the maximum possible rate and minimum encryption overhead respectively on top of any communication network or underlying linear network code. Every generation is first subjected to an encoding by a particular matrix generated by two (or three) Vandermonde matrices, and then parts of coded vectors (or secret symbols) are encrypted before transmitting. The proposed schemes are characterized by tunable and measurable degrees of security and also shown to be of low overhead in computation and bandwidth.

• The Journal of the Korea institute of electronic communication sciences
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• v.19 no.2
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• pp.409-416
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• 2024

With the expansion of floating-point operation requirements for fast high-speed data signal processing and logic operations, the speed of the floating-point operation unit is the key to affect system operation. This paper studies the performance characteristics of different floating-point multiplier schemes, completes partial product compression in the form of carry and sum, and then uses a carry look-ahead adder to obtain the result. Intel Quartus II CAD tool is used for describing Verilog HDL and evaluating performance results of the floating point multipliers. Floating point multipliers are analyzed and compared based on area, speed, and power consumption. The FMAX of modified Booth encoding with Wallace tree is 33.96 Mhz, which is 2.04 times faster than the booth encoding, 1.62 times faster than the modified booth encoding, 1.04 times faster than the booth encoding with wallace tree. Furthermore, compared to modified booth encoding, the area of modified booth encoding with wallace tree is reduced by 24.88%, and power consumption of that is reduced by 2.5%.

• Journal of the Korea Computer Graphics Society
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• v.6 no.4
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• pp.35-42
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• 2000

3D texture mapping generates highly natural visual effects in which objects appear carved from lumps of materials rather than laminated with thin sheets as in 2D texture mapping. Storing 3D texture images in a table for fast mapping computations, instead of evaluating procedures on the fly, however, has been considered impractical due to the extremely high memory requirement. Recently, a practical real-time 3D texture mapping technique was proposed in [11], where they attempt to resolve the potential texture memory problem by compressing 3D textures using a wavelet-based encoding method. In this paper, we consider two other encoding schemes that could also be applied to the compression-based 3D texture mapping. In particular, we extend the vector quantization and FXT1 for 3D texture compression, and compare their performance with the wavelet-based encoding scheme.

• IEIE Transactions on Smart Processing and Computing
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• v.6 no.2
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• pp.117-123
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• 2017

N-continuous orthogonal frequency division multiplexing (OFDM) is a precoding method for sidelobe suppression of OFDM signals and seamlessly connects OFDM symbols up to the high-order derivative for sidelobe suppression, which is suitable for suppressing out-of-band radiation. However, it severely degrades the error rate as it increases the continuous derivative order. Two schemes for orthogonal precoding of N-continuous OFDM have been proposed to achieve an ideal error rate while maintaining sidelobe suppression performance; however, the large size of the precoder matrices in both schemes causes very high computational complexity for precoding and decoding. This paper proposes matrix decomposition of precoder matrices with a large size in the orthogonal precoding schemes in order to reduce computational complexity. Numerical experiments show that the proposed method can drastically reduce computational complexity without any performance degradation.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.12
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• pp.8-16
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• 2010

In this paper, we present a structure of computationally efficient MIMO-OFDM transmitters, using STBC. Straightforward implementation of these systems requires separate WFT processing blocks for each of the transmit antennas. In our proposed scheme, we use symmetry properties of Fourier transform, and thus use a frequency domain encoding strategy. This greatly reduces the computational burden. The proposed scheme uses just a single IFFT block at each OFDM symbol period, and thus resulting in the same complexity as a single antenna OFDM system. As specific examples of the proposed schemes, we present frequency domain encoding matrices for QO-STBC-OFDM and QO-SFBC-OFDM transmitters.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.06a
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• pp.646-651
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• 1998

Fuzzy control has been used successfully in many practical applications. In traditional methods, experience and control knowledge of human experts are needed to design fuzzy controllers. However, it takes much time and cost. In this paper, an automatic design method for fuzzy controllers using genetic algorithms is proposed. In the method, we proposed an effective encoding scheme and new genetic operators. The maximum number of linguistic terms is restricted to reduce the number of combinatorial fuzzy rules in the research space. The proposed genetic operators maintain the correspondency between membership functions and control rules. The proposed method is applied to a cart centering problem. The result of the experiment has been satisfactory compared with other design methods using genetic algorithms.

• Journal of Korea Multimedia Society
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• v.17 no.6
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• pp.697-705
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• 2014

For enhancing network efficiency, content-centric networking (CCN) allows network nodes to temporally cache a transmitted response message(Data) and then to directly respond to a request message (Interest) for previously cached contents. Also, CCN is designed to utilize a hierarchical content-name for transmitting Interest/Data instead of a host identity like IP address. This content-name included in Interest/Data reveals both content information itself and the structure of network domain of a content source which is needed for transmitting Interest/Data. To make matters worse, This content-name is human-readable like URL. Hence, through analyzing the content-name in Interest/Data, it is possible to analyze the creator of the requested contents. Also, hosts around the requester can analyze contents which are asked by the requester. Hence, for securely implementing CCN, it is essentially needed to make the content-name illegible. In this paper, we propose content-name encoding schemes for CCN so as to make the content-name illegible and evaluate the performance of our proposal.

• Journal of Communications and Networks
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• v.5 no.2
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• pp.174-183
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• 2003

Space-Time (ST) codes are known to provide high transmission rates, diversity and coding gains. In this paper, a tight upper bound on the error probability of ST codes over rapid fading channels is presented. Moreover, ST codes suitable for rapid fading channels are presented. These codes are designed using the QPSK and 16-QAM signal constellations. The proposed codes are based on two different encoding schemes. The first scheme uses a single trellis encoder, whereas the second scheme uses the I-Q encoding technique. Code design is achieved via partitioning the signal space such that the design criteria are maximized. As a solution for the decoding problem of I-Q ST codes, the paper introduces a low-complexity decoding algorithm. Results show that the I-Q ST codes using the proposed decoding algorithm outperform singleencoder ST codes with equal complexity. The proposed codes are tested over fading channels with different interleaving conditions, where it is shown that the new codes are robust under such imperfect interleaving conditions.