• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.9 no.2
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• pp.131-140
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• 1998

MAI(Multi-Access Interference) and fast channel variation due to the fading environment are the major problems in the mobile CDMA communication systems. Recently, interest has been increasing in applying the Adaptive Linear MMSE Detector to MAI cancellation in the CDMA reverse link. In this paper, we propose a modified Adaptive Linear MMSE Detector structure which can be used in Long-duration code CDMA system in the presence of independent Rayleigh fading. We use independent multiple tap-weight vector structure to cope with the variation of spreading sequence pattern between neighbor symbols because of the Long-duration code. In this case, more exact channel parameter estimation is required. To solve this problem, we use coherent CDMA structure which can track the channel parameters like amplitude and phase by employing the low power pilot channel in the CDMA reverse link.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.12
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• pp.1408-1418
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• 2007

In this paper, we analyze the performance of pilot symbol assisted channel estimation and equalization schemes for OFDM systems over frequency-selective time-varying channels and propose methods to improve the system performance. In the least square(LS) and linear minimum mean square error(MMSE) channel estimation, time domain windowing is introduced for banding the frequency domain channel matrix. The linear MMSE and decision feedback equalization schemes are employed with the pilot symbols for channel estimation taken into account in the equalization process. To reduce computational complexity, the band LU matrix factorization algorithm is introduced in solving the linear systems involved in the equalization, and the performances are compared with the known previous results by computer simulations. When time domain windowing is employed in the decision feedback equalization, the matrix related with the decision feedback process is shown to be unhanded and the resultant performance degradation is analyzed.

• Proceedings of the KIEE Conference
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• 2003.11b
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• pp.295-298
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• 2003

In this paper, a novel maximum a posterion (MAP) estimation for the channel decoding of H.264 codes in the presence of transmission error is presented. Arithmetic codes with a forbidden symbol and trellis search techniques are employed in order to estimate the best transmitted. And, there has been growing interest of communication, the research about transmission of exact data is increasing. Unlike the case of voice transmission, noise has a fatal effect on the image transmission. The reason is that video coding standards have used the variable length coding. So, only one bit error affects the all video data compressed before resynchronization. For reasons of that, channel needs the channel codec, which is robust to channel error. But, usual channel decoder corrects the error only by channel error probability. So, designing source codec and channel codec, Instead of separating them, it is tried to combine them jointly. And many researches used the information of source redundancy In received data. But, these methods do not match to the video coding standards, because video ceding standards use not only one symbol but also many symbols in same data sequence. In this thesis, We try to design combined source-channel codec that is compatible with video coding standards. This MAP decoder is proposed by adding semantic structure and semantic constraint of video coding standards to the method using redundancy of the MAP decoders proposed previously. Then, We get the better performance than usual channel coder's.

• Journal of Digital Contents Society
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• v.17 no.3
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• pp.203-210
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• 2016

Korean is free of omission of sentence elements and modifying scope, so managing it on morphological analyzer is better than parser. In this paper, we propose functional expansion methods of the morphological analyzer to ease the burden of parsing. This method is a longest phrase matching method. When the series of several morpheme have one syntax category by processing of Unknown-words, Compound verbs, Compound nouns, Numbers and Symbols, our method combines them into a syntactic unit. And then, it is to treat by giving them a semantic features as syntax unit. The proposed morphological analysis method removes unnecessary morphological ambiguities and deceases results of morphological analysis, so improves accuracy of tagger and parser. By empirical results, we found that our method deceases 73.4% of Parsing tree and 52.4% of parsing time on average.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.7C
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• pp.618-627
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• 2010

In this paper, we propose an adaptive K-best algorithm in which the number K of candidates is changed according to the differences of level radii. We also compare the bit error performance and complexity of the proposed algorithm with those of several conventional K-best algorithms, where the complexity is defined as the total number of candidates of which partial Euclidean distances have to be calculated. The proposed algorithm adaptively decides K at each level by eliminating the symbols, whose differences of radii are larger than a threshold, from the set of candidates, and the maximum or average value of differences can be adopted as the threshold. The proposed decoding algorithm shows the better bit error performance and the lower complexity than a conventional K-best decoding algorithm with a constant K, and also has a similar bit error performance and the lower complexity than other adaptive K-best algorithms.

• Journal of the Korea Society for Simulation
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• v.17 no.4
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• pp.1-9
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• 2008

Proposed in the paper is an automated procedure to construct a plant model for PLC simulation. Since PLC programs only contain the control logic without the information on the plant model, it is necessary to build the corresponding plant model to perform simulation. Conventionally, a plant model for PLC simulation has been constructed manually, and it requires much efforts as well as the in-depth knowledge of simulation. As a remedy for the problem, we propose an automated procedure to generate a plant model from the symbol table of a PLC program. To do so, we propose a naming rule for PLC symbols so that the symbol names include enough information on the plant model. By analyzing such symbol names, we extract a plant model automatically. The proposed methodology has been implemented, and test runs were made.

• Journal of Digital Contents Society
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• v.18 no.4
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• pp.649-657
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• 2017

Hayao Miyazaki provides pleasure which go beyond the barrier of culture and language through realizing pan-cultural and mythical space which can communicate with the audience through unique, aesthetic expression. In his animation storytelling, diverse tangible and intangible symbolic elements based on the traditional culture inherent to Japan are actively utilized, and he provides the audience with the aesthetic pleasure of arbitrary interpretation and contemplation by composing the system of connotative signification through such symbols. In this process, he creates the value of the system of meaning which clearly conveys the mythical message of connotative meaning of the work through the aesthetic form based on the universal experience of confrontation and coexistence. It can be said that this is the communicative value of animation storytelling pursued by Hayao.

• The Journal of the Acoustical Society of Korea
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• v.33 no.6
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• pp.407-412
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• 2014

In this paper, we propose an underwater acoustic communication of FH-MFSK(Frequency-Hopped Multiple Frequency Shift Keying) system with multiple orthogonal property. Generally, the processing of FSK(Frequency Shift Keying) method is simple, but it is vulnerable to ISI (Inter-Symbol Interference) caused by multipath transmission. In this paper, the orthogonal codes are generated with the same number of transmitting symbols, and these codes are corresponding to multiple frequencies. We used m-sequence to generate multiple orthogonal codes. We compared the performance of proposed method with conventional MFSK method via the experiment. As a result, we confirmed that the proposed method shows 6~10 % lower error rate at 100 bps than conventional method.

• The Research Journal of the Costume Culture
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• v.18 no.2
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• pp.229-244
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• 2010

This study aims to discuss the type and characteristics of primitivism in the modern fashion of the $21^{st}$ century and, as a research method, the concept of primitivism as well as the transition of the patterns of primitivism expressed in modern art have been considered and reviewed through a variety of references. In particular, an empirical analysis of the works that have been created from 2000 to 2009 has been performed using domestic and overseas fashion and collection magazines. The characteristics of primitivism in modern fashion possess the following types of expression: First, Sensuality can be cited as one of the characteristics, either by using direct or indirect exposure of the human body, a silhouette which fits tightly to the body, or creating the effect of sensual beauty using animal fur or bird feathers. Second, Incantation: Masks symbolizing primitive incantation are used to cover the human face or primitive incantation is incorporated as a theme of hair accessories or fashion trinkets, etc. In addition, such decorations as tattoos and the body colorations of ancient tribes are reproduced in modern fashion by means of body painting, printing or other accessories, emphasizing the image of occult primitiveness. Third, Naturalness can be cited as one of the characteristics. Naturalness is emphasized in modern fashion not through artificial decorations and processing, but rather through different patterns of exposure by which natural purity can be felt or through the use of non-artificial materials which recalls primitive civilization. Forth, Playfulness is expressed in the form of graffiti or abstract letters and paintings, and the character of the play is often expressed by the use of grotesque images based on various distortions and exaggerations of the human body, the utilization of symbols of primitive incantation and body and/or facial painting. Fifth, Lastly 'folkishness is emphasized. Folk-like objects, facial decorations, exposure of the body and intense color contrasts typically represent the folkish characteristics.

• The Research Journal of the Costume Culture
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• v.18 no.5
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• pp.1031-1047
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• 2010

This study examines the conceptual characteristics of fantasy movies. It also studies the process of socio-cultural changes of the mythical images such as heroes, goddesses and the devil that have often become the centre of fantasy movie characters. This study further examines the features of each character that correspond to specific mythical images. The purpose of this research is to suggest the conceptual and aesthetic characteristics of fantasy reflected in the characters and the costumes of fantasy movies, which were released since the year 2000. The followings are the results of the research: The conceptual characteristics of fantasy reflected in the characters and the costumes of fantasy movies are summarized as representation of reality, allegory and symbols, horror, desire, deconstruction and metamorphosis, otherness and counter-cultural sentiments. The aesthetic characteristics of the costumes of fantasy movies are defined as typicality and symbolism, grotesqueness, sensuality, hybridization, and otherness. These characteristics are very interconnected. The costumes of heroic characters appearing in fantasy movies show strong side of standard while the costumes of the evil characters revealed the limit of dualistic point of worldview centered on West. Heroic characters show realistic and human side that reflects the ethos of the time. Negative characters such as the devil or witches, which were created in human imagination and emotion, become the dynamic force of fantasy movies through their deviant actions. Their clothes, with variety and hybridization, become the source of creativity expected in present society.