• The Journal of the Acoustical Society of Korea
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• 제16권3E호
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• pp.50-55
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• 1997

Based on the anthropometric data of Korea male adults, a head and torso simulator(HATS) is constructed to measure its head related transfer functions (HRTFs) which can be used for three dimensional (3-D) sound localization. The HRTFs binaural impulse responses, are measured in an anechoic chamber using a burst maximum length sequence (MLS) signal of 65,535 samples and 32,768 samples acquisition at the sampling rate of 75.47kHz. Also measured are the impulse responses of a driving loudspeaker and some headphones for sound reproduction to get the exact HRTF of the HATS-alone. Through a post-processing procedure, the impulse-version HRTFs at the sampling frequency of 44.1 kHz, which have filter lengths of 512 points, are finally obtained. As an application of the measured HRTFs, a 3-D sound processor for headphone reproduction has been developed. The signal intervals to be processed can be selected and each interval is manipulated to have its diretionality and distance information by using corresponding HRTF and energy control.

• Computational Structural Engineering : An International Journal
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• 제1권1호
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• pp.31-38
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• 2001

In the case of the non-proportionally damped system such as the soil-structure interaction system, the structural control system and composite structures, the eigenproblem with the damping matrix should be necessarily performed to obtain the exact dynamic response. However, most of the eigenvalue analysis methods such as the subspace iteration method and the Lanczos method may miss some eigenvalues in the required ones. Therefore, the eigenvalue analysis method must include a technique to check the missed eigenvalues to become the practical tools. In the case of the undamped or proportionally damped system the missed eigenvalues can easily be checked by using the well-known Sturm sequence property, while in the case of the non-proportionally damped system a checking technique has not been developed yet. In this paper, a technique of checking the missed eigenvalues for the eigenproblem with the damping matrix is proposed by applying the argument principle. To verify the effectiveness of the proposed method, two numerical examples are considered.

• 한국환경독성학회:학술대회논문집
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• 한국환경독성학회 2002년도 추계국제학술대회
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• pp.167-167
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• 2002

Methylmercury (MeHg), one of the heavy metal compound, can cause severe damage to the central nervous system in humans. Many reports have contributed MeHg poisoning to contaminated foods and release into the environment. Despite many studies on the pathogenesis of MeHg-induced central neuropathy, no useful mechanism of toxicity has been established. To find genes differentially expressed by MeHg in neuronal cell, we peformed forward and reverse suppression subtractive hybridization (SSH) method on mRNA derived from neuroblastoma cell line, SH-SY5Y treated with solvent (DMSO) and 6.25 uM (IC$\sub$50/) MeHg. Differentially expressed CDNA clones were sequenced and the mRNAs were re-examined on Northern blots. These sequences were identified by BLAST homology search to known genes or expressed sequence tags (ESTs). Analysis of these sequences has provided an insight into the biological effects of MeHg in the pathogenesis of neurodegenerative disease and a possibility to develop more efficient and exact monitoring system of heavy metals as common environmental pollutants.

• 한국문헌정보학회지
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• 제14권
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• pp.3-18
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• 1987

The factors which can help the library users trace the specific subject that she or he needs are most important, when they are not sure of what they need exactly in front of a classified catalogue. This study is about what the factors are and how the factors affect the inference of users' reasoning structure. Since the classified catalogues are reflected by the classification structure, naturally the logic in the classification system becomes the focus of the study. This study concludes the classification system which enables the library users to use their reasoning capabilities, viz. the classification system which can help the users trace the specific subject even as they are not sure of the exact subject they need has following factors in the system. 1. It should have the validity based on the facts in the components of the classification system. 2. It should be logically arranged when the components of the classification system are placed in due sequence. 3. The notation of the system should be based on mnemonics. The reason is that the indispensable factors in the formation of inference of human reasoning structure are: 1. the premises which are based on the facts and 2. the logical relationship between the premises and conclusions which are induced from the premises.

• 한국통신학회논문지
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• 제35권11B호
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• pp.1725-1731
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• 2010

본 논문은 DS-SS/TDMA 패킷 통신에서 부호획득 성능을 향상시킬 수 있는 프리앰블 구조와 부호획득 방법을 제안한다. 제안된 방법은 프리앰블의 각 구간마다 짧은 확산부호의 위치를 다르게 하교 구간 간의 짧은 확산부호의 위치 차이 및 각 구간의 짧은 확산부호 위치에서 데이터 시작점의 차이를 테이블로 저장함으로써 일부 구간의 수신 오류 시에도 데이터 시작점을 정확하게 판단할 수 있다. 모의실험 결과 제안된 방법은 같은 길이의 짧은 확산부호를 사용할 때 기존 방법에 비해 최소 5dB의 이득이 있으며, 기존보다 1/4 길이의 짧은 확산부호로도 기존방법과 동일한 부호획득 성능을 나타내었다.

• Animal cells and systems
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• 제15권3호
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• pp.243-249
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• 2011

The genetic diversity and population history of the Asian shore crab, Hemigrapsus sanguineus, were investigated with a nucleotide sequence analysis of 536 base pairs (bp) of the mitochondrial cytochrome c oxidase subunit I gene (COI) in 111 samples collected from four populations in Korea and one in Japan. In total, 28 haplotypes were defined by 27 variable nucleotide sites in the COI region examined. The observed haplotypes had a shallow haplotype genealogy and no geographical associations. Most of the populations had high haplotype diversity (0.656-0.788) and low nucleotide diversity (0.00165-0.00244), and significant negative values for Fu's $F_S$, suggesting rapid and recent population growth from an ancestral population and sudden population expansion. The pairwise fixation indices ($F_{ST}$) estimated with the exact test and the migration rates indicate that substantial gene flow occurs among these populations as a result of sea currents, except between the Yellow Sea coast of Korea (BUA) and the Pacific Ocean coast of Japan (JPA). These two populations (BUA and JPA) showed significant genetic differentiation and low migration rate.

• 대한정형외과 초음파학회지
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• 제2권1호
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• pp.37-44
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• 2009

프롤로 치료는 최근에 이완된 인대를 강화시키는 기술로써 점점 더 많이 받아들여지고 있다. 프롤로 치료는 만성통증의 원인이 되는 약해지거나 이완된 인대에 자극성 용액을 주사하는 방법이다. 이 주사행위는 염증반응을 유도하고, 후차적으로 정상적인 회복과정을 밟게 만들고 있다. 하지에서 다양한 근골격계질환, 퇴행성관절염, 인대와 건 손상 등은 프롤로 치료로 치료될 수 있다. 프롤로 치료는 다양한 근골격계질환에서 대단히 우수하고 강력한 비수술적이고, 보존적 치료방법으로 고려될 수 있다. 프롤로치료는 반월상연골 파열, 슬개건 파열 및 병변, 햄스트링 파열 등 다양한 질환에서 효과적이고 우수한 치료효과를 보여주고 있다. 프롤로치료를 하면서 초음파 검사를 병행할 때는 질환의 정확한 병변을 찾고 확인하며 치료과정에 따라 임상적인 경과를 점검하는데 대단히 유용한 도구가 될 수 있다. 프롤로 치료를 시행하면서 초음파 검사를 병행할 때 추시한 결과를 함께 제시할 수 있다.

• 한국통신학회논문지
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• 제28권3C호
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• pp.279-285
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• 2003

본 논문에서는 채널 추정 과정이 필요하지 않은 블라인드 결정 궤환 등화기를 제안하였다. 등화기 계수는 수신신호의 이차 통계 특성을 이용하여 직접 얻어진다. 최적화된 다단계 예측 오류 필터(PEF)의 출력은 채널의 부분응답과 송신 신호열의 곱으로 표현되기 때문에, 역방향 다단계 PEF는 블라인드 결정 궤환 등화기의 피드포워드필터 (FFF)로 사용될 수 있다. 또한 이에 따른 피드백 필터는 심볼율 부분 채널 응답을 통해서 얻어진다. 제안되는 기법은 정확한 채널의 길이를 알지 않아도 안정적인 성능을 가진다는 점에서 기존의 블라인드 채널 추정기법에 비해 장점을 가진다.

• ETRI Journal
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• 제30권4호
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• pp.576-586
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• 2008

In most parallel loops of embedded applications, every iteration executes the exact same sequence of instructions while manipulating different data. This fact motivates a new compiler-hardware orchestrated execution framework in which all parallel threads share one fetch unit and one decode unit but have their own execution, memory, and write-back units. This resource sharing enables parallel threads to execute in lockstep with minimal hardware extension and compiler support. Our proposed architecture, called multithreaded lockstep execution processor (MLEP), is a compromise between the single-instruction multiple-data (SIMD) and symmetric multithreading/chip multiprocessor (SMT/CMP) solutions. The proposed approach is more favorable than a typical SIMD execution in terms of degree of parallelism, range of applicability, and code generation, and can save more power and chip area than the SMT/CMP approach without significant performance degradation. For the architecture verification, we extend a commercial 32-bit embedded core AE32000C and synthesize it on Xilinx FPGA. Compared to the original architecture, our approach is 13.5% faster with a 2-way MLEP and 33.7% faster with a 4-way MLEP in EEMBC benchmarks which are automatically parallelized by the Intel compiler.

• 한국컴퓨터정보학회논문지
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• 제4권3호
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• pp.28-34
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• 1999

본 논문에서는 DCT 영역에서 DCT블록내의 DC성분과 매크로블록내의 움직임 벡터성분을 이용하여 동영상 장면전환 자동 검출에 관한 방법을 제안한다. 제안하는 방법은 압축된 MPEG 신호열내의 픽쳐 종류와 상관없이 임의의 신호열에서 장면전환을 검출한다. 이를 위해 MPEG 신호열의 DCT 영역에서 픽쳐구성요소의 특징을 이용하여 새로운 비교잣대를 정의하고 움직임 벡터에 예민한 B-picture 의 특성을 이용하여 정확한 장면전환을 검출한다. 이때. I-picture를 가지고 급격한(cut) 장면전환을 검출하고 P. B picture 를 가지고 점진적인(gradual) 장면 전환을 검출한다. 제안한 방법은 다양한 MPEG 신호열에 대하여 시험결과 그 효율성이 우수함을 보인다.