• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.6A
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• pp.438-449
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• 2012

This paper presents new CRC-p codes for VHF band maritime wireless communication system based on performance analysis of various CRC codes. For this purpose, we firstly describe the method of determination of undetected error probability and minimum Hamming distance according to variation of CRC codeword length. By using the fact that the dual code of cyclic Hamming code and primitive BCH code become maximum length codes, we present an algorithm for computation of undetected error probability and minimum Hamming distance where the concept of simple hardware that is consisted of linear feedback shift register is utilized to compute the weight distribution of CRC codes. We also present construction of transmit data frame of VHF band maritime wireless communication system and specification of major communication parameters. Finally, new optimal CRC-p codes are presented based on the simulation results of undetected error probability and minimum Hamming distance using the various generator polynomials of CRC codes, and their performances are evaluated with simulation results of bit error rate based on the Rician maritime channel model and ${\pi}$/4-DQPSK modulator.

• The Journal of the Korea Contents Association
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• v.19 no.10
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• pp.217-225
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• 2019

National research and development(R&D) information is information generated in the process of performing R&D based on programs and projects issued by national government departments, and includes information from various research fields as ordered by various departments. Therefore, for efficient R&D information retrieval, it is necessary to build a national R&D terminology dictionary that can reflect the characteristics of such national R&D information. In this study, we propose a method for constructing a national R&D terminology dictionary by applying the classification of science and technology standards used to specify the research field in national R&D information. We will discuss the structural characteristics of national R&D project information and the usefulness of the project keyword, and explain the status of national R&D information by the National Standard Science and Technology Classification(NSSTC) Codes and the characteristics of the national R&D terminologies. Based on this, a method for building a national R&D terminology dictionary is defined in terms of the type and structure of the terminology dictionary, preliminary construction procedures, and refining rules. The national R&D terminology dictionary built on the basis of this study can be used in various ways such as expansion of search terms using Korean-English equivalent words and synonyms when searching national R&D information, clarifying the scope of search using NSSTC, and providing user convenience functions using term explanation information.

• Annual Conference of KIPS
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• 2002.11a
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• pp.619-622
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• 2002

동사패턴은 원시 언어 분석을 위해 동사와 동사의 격성분 및 의미제약을 기술하고, 목적언어 생성을 위해 동사의 대역어 및 격성분들의 생성 위치정보를 기술한다. 이러한 동사패턴의 구축은 시간적, 경제적 부담이 큰 작업이며, 동사패턴 구축의 자동화 혹은 반자동화에 대한 요구는 크다. 본 논문에서는 서술성 명사와 결합하여 동사를 생성하는 접사들인 '-하-, -되-, -받-, -당하-, -드리-'에 대해, 이들 간의 상호 변환 규칙을 이용하여 수동으로 구축된 동사패턴으로부터 새로운 동사패턴을 자동으로 생성한다. 변환 규칙에서는 명사 어휘별 접사 분포 정보와 함께, 접사와 결합된 파생동사의 구문정보가 요구된다. 그러나, 기존의 사전에는 서술성 명사들의 '-하다, -되다' 분포 및 구문정보만이 기술되어 있고, '-받다, -당하다, -드리다'에 대해서는 기술되어 있지 않다. 본 논문에서는 서술성 명사들의 접사 분포 정보 및 구문정보를 파악하고, 이들 간의 상호 변환 규칙을 도출하여 새로운 동사패턴을 생성화는 2단계 작업을 수행한다.

• Proceedings of the KSPS conference
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• 2002.11a
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• pp.183-186
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• 2002

The speech detection is one of the important problems in real-time speech recognition. The accurate detection of speech boundaries is crucial to the performance of speech recognizer. In this paper, we propose a speech detector based on Mel-band selection through training. In order to show the excellence of the proposed algorithm, we compare it with a conventional one, so called, EPD-VAA (EndPoint Detector based on Voice Activity Detection). The proposed speech detector is trained in order to better extract keyword speech than other speech. EPD-VAA usually works well in high SNR but it doesn't work well any more in low SNR. But the proposed algorithm pre-selects useful bands through keyword training and decides the speech boundary according to the energy level of the sub-bands that is previously selected. The experimental result shows that the proposed algorithm outperforms the EPD-VAA.

• The Journal of the Acoustical Society of Korea
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• v.17 no.2
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• pp.18-24
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• 1998

선박내의 작업 환경에서 발생하는 소음은 엔진, 발전기, 펌프와 같은 다양한 소음원 에 기인하다. 이들은 대체적으로 저주파 대역에서 주기성을 가지며, 이로 인해 능동 소음 제 어 기법이 적용될 수 있다. 이 논문에서는 선박내 소음 환경을 개선하기 위해 소음 흡음 재·차단재를 이용한 헤드폰 착용과 같은 수동적인 방법이 아니라, 작업 상황에 따라 소음 을 줄이기 위한 능동소음제어(ANC: Active Noise Control) 시스템을 구현한다. 특히 선박내 의 침실 공간으로 적용 가능성을 컴퓨터 시뮬레이션을 통해 고찰하고, TMS320C50 DSP를 포함한 하드웨어 구성을 통해 그 성능을 실험하고 평가한다.

• Annual Conference on Human and Language Technology
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• 2009.10a
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• pp.92-96
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• 2009

인간이 가진 개념을 지식베이스화하려는 시도 중 하나로 의미망이 구축되고 있다. 한국어를 대상으로 한 어휘 의미망 중 프린스턴 대학의 WordNet을 대역한 KorLex는 1,2단계에서 한국어 어휘의미의 특성을 반영하여 개념 및 의미구조를 재구조화하고 있다. 그러나 현재 KorLex의 동의어 집합을 구성하는 어휘 의미에는 논항정보를 따로 구성할 수 없었다. 본 연구는 세종 전자 사전 격틀정보내의 선택제약조건(selectional restriction)으로 사용되고 있는 의미 부류와 KorLex의 명사 어휘 의미망을 자동 맵핑하는 방안을 제안함으로써 KorLex에서 세종 전자 사전 격틀정보를 활용할 수 있는 가능성을 제공한다.

• Journal of KIISE:Software and Applications
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• v.32 no.4
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• pp.300-311
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• 2005

Terms are linguistic realization of technical concepts. Term constituents are important elements used for representing the concept. Since many new terms are created from the modification or combination of existing constituents, it is important to analyze term constituents for understanding the concept of the term. It means that term constituents offer clues for understanding the concept of terms. However, there are a couple of difficulties in matching concept unit and term constituents such as mismatching between a term constituent and a concept unit, homonym of term constituents and synonym of term constituents. To solve them, it is necessary to recognize concept units of term constituents. In this paper, we define an English term constituent as the concept unit and use an alignment algorithm between English-Korean term constituents in order to recognize concept units of term constituents. By our alignment algorithm we recognize Korean term constituents corresponding to an English term constituent with about $93\%$ precision.

• Journal of Satellite, Information and Communications
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• v.1 no.2
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• pp.71-75
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• 2006

This paper describes operation plans for satellite communications system (SATCOM) which is consisted of Ka band communication payload, geostationary satellite control system and communication test earth station system for the communication, ocean and meteorological satellite system (COMS). Also this paper describes the communication service and mission plans by each system of the SATCOM, and configurations and functions of the system interface between each system. Especially this paper proposes operational items, functions and their configuration diagrams, touches their operational plans. This paper describes function definitions, configuration diagram and operation plans of the PCS )Payload Control System) for monitor and control of the communication payload and communication service network of the SATCOM.

• The Journal of the Acoustical Society of Korea
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• v.15 no.6
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• pp.110-116
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• 1996

In this paper a novel method improving the accuracy of DTMF tone reception in ARS system is proposed. ARS system should allow users to generate DTMF signals while it is sending voice guidance. It is not unocmmon, in this case, that a portion of transmitting voice signals cross-talks to the receiving channel and it often results in interfering with the receiving DTMF signals. Serious degradations including DTMF tone missing, false alarm and so forth have been introduced for the above reason. To overcome this phenomena, we have proposed a way eliminating the frequency spectra representing DTMF signals bands from the transmitting voice signal by using notch filters. This method also employs bandpass filters of which the frequency responses are reciprocal to those of the notch filters incorporated with the DTMF receiver. It is shown that a drastic improvement has been achieved with respect to the DTMF tone detection with little deterioration of voice guidance quality.

• Journal of Information Management
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• v.28 no.3
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• pp.46-73
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• 1997

In these days, there are many studies to improve the effectiveness of retrieval systems. One method is to use thesaurus in the systems. But the establishment of the saurus independently is very difficult and requiers a great deal of time and labor. The goal of this research is to examine which problems there are. The texts used in the thesis were "Thesaurus of ERIC descriptors(7th ed.1977)" and "KEID Thesaurus(1981)" established by translation. The results of the thesis were as follows, First, there were many differences of equivalence classes of terms between English and Korean. Second, the errors of translation made words inadequate to use as a descriptors. Third, because of differences of traditions, thought and culture, associative relationship and hierarchical relation did not coincide between terns, Fourth, because the terms of the thesaurus of ERIC descriptors serve Western usages, the terms used in Korea were not or insufficient. So it way necessary to add our own therms. As mentioned above, translating a thesaurus for use as a documentation language for indexing and retrieval is not the optimum way of building up a thesaurus.