• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 제14회 신호처리 합동 학술대회 논문집
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• pp.613-616
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• 2001

본 논문에서는 3GPP에 규격으로 채택된 전송 다이버 시티 기법들 중에 이상적인 상황에서 가장 우수한 성능을 갖는 폐쇄루프 전송 다이버시티 (CLTD : Closed Loop Transmit Diverstiy) 기법과 선형 사전필터의 조합을 통해 MISO 시스템에서 보다 우수한 성능의 전송 다이버시티 기법을 제안하고 이에 대한 성능을 분석하였다. 또한 사전필터의 최적의 필터 계수 값을 사용하여 다이버시티이득을 최대화하였고 이에 대한 성능을 분석한 결과 CLTD 기법보다 월등히 우수한 성능을 확인하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 하계종합학술대회 논문집
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• pp.465-467
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• 1989

Many Korean graphic cards have been produced. But, due to the diversity of korean code system all korean graphic cards produced have been adapted in specific code system. Therfore, considering in KSC-5601-1987, the paper propose a Korean decoder independent of code system

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2007년도 하계종합학술대회 논문집
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• pp.69-70
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• 2007

The code division multiple access (CDMA) system capacity is limited by the amount of interference of the system. To reduce the unnecessary interference, this paper proposes optimized cell identification (ID) codes for site selection diversity transmission (SSDT) power control in wideband code division multiple access system of third generation partnership project (3GPP). The proposed SSDT cell ID codes are designed to minimize the problem and to be easily decoded using simple fast Hadamard transformation (FHT) decoder.

• 농업과학연구
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• 제45권1호
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• pp.28-37
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• 2018

This study was done to develop environmental risk assessments and a biosafety guide for insect-resistant genetically modified rice at a LMO (Living Modified Organism) isolation field. In the LMO quarantine area of Kyungpook National University, the species diversities and population densities of non-target insects found on insect-resistant genetically modified rice (Bt-9) resistant to Cnaphalocrocis medinalis and on non-GM rices (Dongjin and Ilmi) were investigated. The Bt-9 event was therefore evaluated under field conditions to detect possible impacts on the above ground insects and spiders. The study compared transgenic rice and two non-GM reference rices, Ilmi and Dongjin, at Gunwi in Southern Korea in 2016. Each rice was grown on three $18m^2$ plots with a randomized block design. A total of 4,243 individuals from 43 families and 9 orders were collected from the LMO isolation field. In the three types of rice fields, a total of 1,467 individuals from the insect-resistant genetically modified rice (Bt-9), 1,423 individuals from the Ilmi, and 1,353 individuals from the Dongjin were collected, respectively. There was no difference between the population densities of the non-target insect pests, natural enemies and other insects on the insect-resistant genetically modified rice (Bt-9) and non-GM rices. These results provide the diversity and population density of non-target insects for an environment risk assessment survey on insect-resistant genetically modified rice and could be used as a guideline to make a biosafety assessment method for genetically modified crops.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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• pp.196-199
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• 2004

This paper presents a structure of the searcher using the space diversity in array antenna system operating in the DS/CDMA signal environments. The new technique exploits the fact that the In-phase and Quadrature components of interferers can respectively be viewed as independent Gaussian noise at each antenna element in most practical CDMA (Code Division Multiple Access) signal environments. The proposed PN acquisition scheme is a single dwell serial PN acquisition system consisting of two stage, that is, the searching stage and the verification stage. The searching stage correlates the received signals with the local PN oscilator for obtaining the synchronous energy at the entire uncertainty region. The verification stage compares the searching energy with the optimal threshold, which is pre-designed in the Lock-Detector, and decides whether the acquisition is successful or fail. In this paper, we analyzed the relationship of both diversity order and the mean acquisition time. In general, It is known that the mean acquisition time decreases significantly as the number of antenna elements increases. But, the enhancement of the performance is saturated in terms of PN acquisition scheme. Therefore, to decrease the mean acquisition time, we must design the optimal array antenna system by considering the operating SNR range of the receiver, the detection probability, and the false alarm probability. The performance of the proposed acquisition scheme is analyzed in frequency-selective Rayleigh fading channels. In this paper, the effect of the number of antenna elements on acquisition scheme is considered in terms of the detection probability, false alarm probability. and the mean acquisition time.

• 한국전자파학회논문지
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• 제20권8호
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• pp.761-769
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• 2009

본 논문에서는 FM 라디오 수신을 위한 차량용 온-글래스 안테나 간의 채널 용량과 다이버시티 이득에 대하여 연구하였다. 안테나 간의 상관 계수 및 채널 용량은 도심 환경에 해당하는 Rayleigh 채널 환경과 안테나의 시뮬레이션 3차원 복사 패턴을 이용하여 계산하였다. 직선형 안테나와 L자형 안테나를 이용하여 채널 용량을 계산하였고 안테나의 급전 위치 및 L자형 안테나의 형상을 변화시켜 채널 용량 변화를 확인하였다. 실제 세단에 적용가능한 급전 위치를 가지며 채널 용량이 높은 안테나 형상을 후면 글래스에 인쇄하여 야외 약전계 지역에서 FM 수신 출력을 측정하였으며, 안테나 수신 신호 간의 상관 계수는 0.65로 낮은 값을 보였다 차량용 온-글래스 안테나에서 높은 다이버시티 이득을 얻기 위해서는 안테나 간의 급전 위치가 최대한 이격되어야 하며, 급전간 거리가 일정 이상 확보되었을 때에는 안테나의 편파가 달라야 함을 확인하였다.

• 한국콘텐츠학회논문지
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• 제11권7호
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• pp.9-20
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• 2011

본 논문은 가상세계속의 가상인간의 다양한 행동들을 제한된 개수의 기본행동들로써 구현하고자 한다. 먼저 객체들의 속성과 행동 등을 통합적으로 나타내주는 지식베이스인 온톨로지를 사용하여 다양한 행동들을 행동계층구조로 조직하고 그 속에서 행동들은 세부 행동들로 구체화한다. 가상인간의 기본행동은 기초 동작들의 조합으로 만들어지고 기본행동들을 최대한 재사용함으로써 다양한 행동들을 효과적으로 구현할 수 있게 설계한다. 이 때 기본행동들을 정밀성이나 사실성보다 간소함과 다양성에 초점을 맞추어 구현하고자 한다. 이를 바탕으로 가상 에이전트들의 특성을 파악하고 특성에 따라 에이전트가 고유의 패턴을 가지고 동작을 생성하는 방법을 개발한다. 또한 가상의 에이전트가 주변의 정성적 변화에 적응하여 동작을 변화하는 방법을 제시한다. 이렇게 제시된 방법들을 인간의 실제 움직임들 즉, 걷기, 달리기, 던지기 등의 동작에 적용해 실현가능성을 검증한다.

• Asian-Australasian Journal of Animal Sciences
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• 제27권9호
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• pp.1263-1269
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• 2014

Comprehensive information on genetic diversity and introgression is desirable for the design of rational breed improvement and conservation programs. Despite the concerns regarding the genetic introgression of Western pig breeds into the gene pool of the Korean native pig (KNP), the level of this admixture has not yet been quantified. In the present study, we genotyped 93 animals, representing four Western pig breeds and KNP, using the porcine SNP 60K BeadChip to assess their genetic diversity and to estimate the level of admixture among the breeds. Expected heterozygosity was the lowest in Berkshire (0.31) and highest in Landrace (0.42). Population differentiation ($F_{ST}$) estimates were significantly different (p<0.000), accounting for 27% of the variability among the breeds. The evidence of inbreeding observed in KNP (0.029) and Yorkshire (0.031) may result in deficient heterozygosity. Principal components one (PC1) and two (PC2) explained approximately 35.06% and 25.20% of the variation, respectively, and placed KNP somewhat proximal to the Western pig breeds (Berkshire and Landrace). When K = 2, KNP shared a substantial proportion of ancestry with Western breeds. Similarly, when K = 3, over 86% of the KNP individuals were in the same cluster with Berkshire and Landrace. The linkage disquilbrium (LD) values at $r^2_{0.3}$, the physical distance at which LD decays below a threshold of 0.3, ranged from 72.40 kb in Landrace to 85.86 kb in Yorkshire. Based on our structure analysis, a substantial level of admixture between Western and Korean native pig breeds was observed.

• 한국전자파학회논문지
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• 제16권1호
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• pp.9-18
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• 2005

본 논문은 격리도가 향상된 US-PCS 대역 댁내용 중계기 안테나를 제안하였다. 일반적으로 중계기는 송신신호와 수신 신호 사이의 간섭을 줄이기 위해 격리도 확보가 필요하다. 그러므로 선형 편파 특성이 우수한 IBD(Integrated Balun Dipole) 안테나에 편파 다이버시티 기법과 캐버티, 멀티 캐버티, 개구정합 방법을 사용하여 안테나의 전후방비 개선을 위한 연구를 하였다. 시뮬레이션과 측정을 통해 개구 정합 방법과 편파 다이버시티 기법을 동시에 사용한 안테나는 US-PCS 대역에서 VSWR < 1.5의 대역폭, 8 dBi 이상의 이득, 그리고 약 15$\~$24dB의 격리도 개선효과가 있음을 확인하였다.

• Journal of Communications and Networks
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• 제2권1호
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• pp.76-84
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• 2000

Communication systems, including cell-based mobile communication systems, multiple satellite communication systems of multi-beam satellite systems, require reliable handoff methods between cell-to-cell, satellite-to-satellite of beam-to-team, respectively. Recent measurement of a CDMA cellular system indicates that the system is in handoff at about 35% to 70% of an average call period. Therefore, system reliability during handoff is one of the major system performance parameters and eventually becomes a factor in the overall system capacity. This paper presents novel and improved techniques for handoff in cellular communications, multi-beam and multi-satellite systems that require handoff during a session. this new handoff system combines the soft handoff mechanism currently implemented in the IS-95 CDMA with code and packet diversity combining techniques and an iterative decoding algorithm (Turbo Coding). the Turbo code introduced by Berrou et all. has been demonstrated its remarkable performance achieving the near Shannon channel capacity [1]. Recently. Turbo codes have been adapted as the coding scheme for the data transmission of the third generation international cellular communication standards : UTRA and CDMA 2000. Our proposed encoder and decoder schemes modified from the original Turbo code is suitable for the code and packet diversity combining techniques. this proposed system provides not only an unprecedented coding gain from the Turbo code and it iterative decoding, but also gain induced by the code and packet diversity combining technique which is similar to the hybrid Type II ARQ. We demonstrate performance improvements in AWGN channel and Rayleigh fading channel with perfect channel state information (CSI) through simulations for at low signal to noise ratio and analysis using exact upper bounding techniques for medium to high signal to noise ratio.