• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2006.05a
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• pp.63-72
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• 2006

정보화 시대에 있어 급변하는 기술발전과 함께 인간의 문화적 욕구가 증대됨에 따라 3차원 공간정보에 대한 수요가 증가하고 있다. 하지만 현재 3차원 공간정보를 구축하는 과정은 일반적으로 수작업 또는 반자동에 의해 이루어지고 있다. 이는 데이터의 구축 및 표현에 많은 시간과 비용이 소요된다는 제약을 가지고 있다. 따라서 본 연구에서는 3차원 symbol 라이브러리를 구축하여 분류된 객체에 부합되는 3차원 symbol을 자동으로 선택하며, 선택된 3차원 symbol을 파라메타를 이용하여 자동으로 mapping 하는 과정을 구축하였다. 이를 통해 3차원 공간데이터의 구축 및 표현에 요구되는 시간과 오류를 최소화할 수 있었다. 또한 LiDAR(Light Detection And Range) 데이터의 3차원 정보를 활용하여 symbol의 자동 mapping을 위한 파라메타들을 산출하였고, symbol의 분류를 위한 기본 데이터로 활용하였다. 구축된 알고리즘의 평가를 위하여 실재 데이터의 3차원 공간데이터베이스를 구축하였다. 구축된 데이터에 대해 symbol선택 및 자동 mapping 과정에 대한 오류 검사를 수행하였고, 더불어 구축된 3차원 데이터의 활용 가능성을 평가하였다. 그 결과 본 연구로부터 구축된 알고리즘들은 3차원 공간정보를 표현함에 있어 신속하고 안정적으로 기여할 수 있을 것으로 판단되었다.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.3
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• pp.417-424
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• 2001

This paper proposes new symbol mapping method that can enhance the performance of trellis coded M-ary PSK compared with conventional symbol mapping methods in AWGN environment. Since the basic criteria of TCM design is Maximum Euclidean distance in AWGN, conventional symbol mapping method keep this basic criteria. In this paper, proposed new symbol mapping method uses both Euclidean distance and Hamming distance to design, while conventional methods make use of only optimal Euclidean distance. New symbol mapping method show the better BER performance than the other through computer simulation and error equations.

• Proceedings of the KSRS Conference
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• v.2
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• pp.896-898
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• 2006

Geological symbols are used for describing geological information. But it's not ease to represent them in commercial GIS s/w, because of their complexity and diversity. This study aims at developing the geological symbol mapping tool for representing geological symbol on user's geological information. Geological symbol mapping too is a web application which can handle SHP format and map geological symbols based on user's requests. It manages geological symbols and mapping codes and symbols are mapped within the geological boundary according to the corresponding non-spatial field that is a mapping code. The system has functions to upload a user's GIS file, and download the converted image file which is mapped geological patterns. The system displays converted images to be check mapping results. Because the symbols are simple bitmap files, user(system manager) can design and apply them rapidly without considering specific commercial S/W. Thus, it is expected that this system plays an important role to disseminate geological standards such as geological symbols. And the results of this study can be used for developing global geological symbols and applying them easily

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.5C
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• pp.432-438
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• 2010

In this paper we study the effect of bit-to-symbol mappings on the convergence behavior of turbo equalizers employing low-density parity-check (LDPC) codes over high order modulations. We analyze the effective SNR of the outputs from linear minimum mean-squared error (MMSE) equalizers and the convergence property of LDPC decoding for different symbol mappings. Numerical results show that the bit-reliability (BR) mapping provides better performance than random mapping in LDPC-coded turbo equalizers over high order modulations. We also verify the effect of symbol mappings through the noise threshold and error performance.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.9C
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• pp.841-847
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• 2009

In this paper we propose a high-performance Hybrid ARQ scheme employing Chase combining based on LDPC (Low-Density Parity-Check) codes. The proposed scheme uses symbol mapping diversity and turbo demodulation to improve decoding performance. We analyze the performance of the proposed scheme by EXIT (EXtrinsic Information Transfer) chart and compare its performance with several symbol mappings.

• Journal of Korean Philosophical Society
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• v.152
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• pp.59-79
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• 2019

The main purpose of this paper is to critically examine the intractable problems of Peirce's notion of 'symbol' as a higher and perfect mode of sign, and present a more appropriate account of the higher status of symbol from an experientialist perspective. Peirce distinguished between icon, index, and symbol, and suggested symbol to be a higher mode of sign, in that it additionally requires "interpretation." Within Peirce's picture, the matter of interpretation is to be explained in terms of "interpretant," while icon or index are not. However, Peirce's conception of "interpretant" itself remains fraught with intractable opacities, thereby leaving the nature of symbol in a misty conundrum. Drawing largely on the experientialist account of the nature and structure of symbolic experience, I try to explicate the complexity of symbol in terms of "the symbolic mapping." According to experientialism, our experience consists of two levels, i.e., physical and symbolic. Physical experience can be extended to symbolic level largely by means of "symbolic mapping," and yet is strongly constrained by physical experience. Symbolic mapping is the way in which we map part of certain physical experience onto some other area, thereby understanding the other area in terms of the mapped part of the physical experience. According to this account, all the signs, icon, index, and symbol a la Peirce, are constructed by way of symbolic mapping. While icon and index are constructed by mapping physical level experience onto some signifier(i.e. Peirce's "representamen"), symbol is constructed by mapping abstract level experience onto some signifier. Considering the experientialist account that abstract level of experience is constructed by way of symbolic mapping of physical level of experience, the symbolic mapping of abstract level of experience onto some other area is a secondary one. Thus, symbol, being constructed by way of secondary or more times mapping, becomes a higher level sign. This analysis is based on the idea that explaining the nature of sign is a matter of explaining that symbolic experience, leaving behind Peirce's realist conception of sign as a matter of an event or state of affairs out there. In conclusion, I suggest that this analysis will open up new possibilities for a more appropriate account of the nature of signs, beyond Peirce's complicated riddles.

• Proceedings of the KSRS Conference
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• v.1
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• pp.106-109
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• 2006

Over the years, many researches have been performed to create 3D digital maps. Nevertheless, it is still time-consuming and involves a high cost because a large part of 3D digital mapping is conducted manually. To compensate this limitation, we propose methodologies to represent 3D objects as 3D symbols and locate these symbols into a base map automatically. First of all, we constructed the 3D symbol library to represent 3D objects as 3D symbols. In the 3D symbol library, the attribute and geometry information are stored, which defines factors related to the types of symbols and related to the shapes respectively. These factors were used to match 3D objects and 3D symbols. For automatic mapping of 3D symbols into a base map, we used predefined parameters such as the size, the height, the rotation angle and the center of gravity of 3D objects which are extracted from Light Detection and Ranging (LIDAR) data and 2D digital maps. Finally, the 3D map in urban area was constructed and the mapping results were tested using aerial photos as reference data. Through this research, we can identify that the developed the algorithms can be used as effective techniques for 3D digital cartographic techniques

• Journal of Information Processing Systems
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• v.12 no.2
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• pp.322-331
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• 2016

Image compression is an essential technique for saving time and storage space for the gigantic amount of data generated by images. This paper introduces an adaptive source-mapping scheme that greatly improves bit-level lossless grayscale image compression. In the proposed mapping scheme, the frequency of occurrence of each symbol in the original image is computed. According to their corresponding frequencies, these symbols are sorted in descending order. Based on this order, each symbol is replaced by an 8-bit weighted fixed-length code. This replacement will generate an equivalent binary source with an increased length of successive identical symbols (0s or 1s). Different experiments using Lempel-Ziv lossless image compression algorithms have been conducted on the generated binary source. Results show that the newly proposed mapping scheme achieves some dramatic improvements in regards to compression ratios.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.6A
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• pp.607-613
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• 2008

In this paper, we investigate the performance of SMP-assisted 3GPP GERAN evolution system employing high order modulation and turbo coding. When applying the SMP which maps systematic bits into highly reliable bit positions, it is confirmed that there is the performance gain for the modulation and coding schemes of 16QAM(DAS-8) as well as 32QAM(DAS-11) by link level simulation.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.4A
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• pp.386-393
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• 2010

In this paper, we analyse HARQ scheme that utilizes symbol mapping diversity (SMD) techniques such as MDSM and CORE. The exploitation feasibility of MDSM and CORE is evaluated in the perspective of system complexity and storage capacity as we consider a BICM system based on 3GPP LTE standards and multipath fading channels. Also, a simple method which obtains SMD effects by circularly shifting bit-block in a codeword is proposed. The experimental results performed in BICM-OFDM systems with single antenna as well as multiple antennas show that frame error rate of the proposed method is close to that of CORE while having lower complexity.