• 제목/요약/키워드: Local spectrum

검색결과 334건 처리시간 0.025초

감각에의한 감성특성의 뇌파변화

  • 황민철;손진훈;김철중
    • 대한인간공학회:학술대회논문집
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    • 대한인간공학회 1996년도 추계학술대회논문집
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    • pp.66-71
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    • 1996
  • This study is to observe human observe human positive and negative sensibility according to modalities such as auditory, visual, olfactory and tactile sense. Twenty university students are participated in this study. Experiment is performed in the subject room specially designed. Measurement system is Spectrum 32 (Cadwell) and is capable of brain mapping. The results shows brain local areas showing statistically significant difference between the positive and negative sensibility in ergonomics.

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무선 LAN 시스템에서 FHSS을 위한 직접형 디지틀 주파수 합성기에 대한 연구 (Study of the Direct Digital Frequency Synthesizer for FHSS in Wireless LAN Systems)

  • 임세홍;장용수;이완범;김환용
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1999년도 하계종합학술대회 논문집
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    • pp.45-48
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    • 1999
  • The demands of WLAN(Wireless Local Area Network) systems increase rapidly in whole society and this phenonenon has been expected that WLAN wi11 substitute for wired-LAN. The FHSS(Frequency Hopped Spread Spectrum) method using the WLAN is changed to the performance of Frequency synthesizer. In this paper, we proposed pipeline-accumulator using ring-counter method instead of constant accumulator that has demerits of size and power consumption. Designed DDFS generated operating frequency of 167MHz and maximum output frequency of 83.5MHz.

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한국어 단독 숫자음 인식을 위한 DTW 알고리즘의 비교 (Comparison of the Dynamic Time Warping Algorithm for Spoken Korean Isolated Digits Recognition)

  • 홍진우;김순협
    • 한국음향학회지
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    • 제3권1호
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    • pp.25-35
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    • 1984
  • This paper analysis the Dynamic Time Warping algorithms for time normalization of speech pattern and discusses the Dynamic Programming algorithm for spoken Korean isolated digits recognition. In the DP matching, feature vectors of the reference and test pattern are consisted of first three formant frequencies extracted by power spectrum density estimation algorithm of the ARMA model. The major differences in the various DTW algorithms include the global path constrains, the local continuity constraints on the path, and the distance weighting/normalization used to give the overall minimum distance. The performance criterias to evaluate these DP algorithms are memory requirement, speed of implementation, and recognition accuracy.

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ON LOCAL SPECTRAL PROPERTIES OF GENERALIZED SCALAR OPERATORS

  • Yoo, Jong-Kwang;Han, Hyuk
    • 충청수학회지
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    • 제23권2호
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    • pp.305-313
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    • 2010
  • In this paper, we prove that if $T{\in}L$(X) is a generalized scalar operator then Ker $T^p$ is the quasi-nilpotent part of T for some positive integer $p{\in}{\mathbb{N}}$. Moreover, we prove that a generalized scalar operator with finite spectrum is algebraic. In particular, a quasi-nilpotent generalized scalar operator is nilpotent.

Phase Offset Enumeration Method with Error Detection and Its Application to Synchronization of PN Sequences

  • Song Young-Joan
    • Journal of electromagnetic engineering and science
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    • 제5권1호
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    • pp.26-30
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    • 2005
  • It is important to know phase offsets of PN(Pseudo Noise) sequences in spread spectrum communications since the acquisition is equivalent to making a phase offset between a receiving PN sequence and a PN sequence of local PN generator be identical. In this paper, a phase offset enumeration method for PN sequences with error detection, and its application to the synchronization are proposed. The phase offset enumeration for an n-tuple PN sequence and its error detection are performed when one period of the sequence is received. Once the phase offset of the receiving sequence is calculated, we can easily accomplish the synchronization by initializing shift registers of a local PN generator according to the phase offset value. The mean acquisition time performance of the proposed scheme was derived analytically. Since this synchronization scheme can be realized by using simple circuit and acquires very rapid acquisition in high SNR but shows performance degradation in low SNR, it can be especially useful in indoor and office environments.

[ $^{13}CO$ ] OBSERVATIONS OF CMa OB1/RA REGION

  • KIM BONG GYU;KAWAMURA AKINO;FUKUI YASUO
    • 천문학회지
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    • 제29권spc1호
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    • pp.193-194
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    • 1996
  • A large scale $^{13}CO$(J=1-0) survey was made for CMa OB1/R1 region in $220^{\circ}{\le}{\iota}{\le}230^{\circ}$ and $-10^{\circ}{\le}b{\le}10^{\circ}$ with a 8' spacing by using the 4 m radio telescope of Nagoya University. 34 isolated clouds were identified in this survey. Among them, two clouds were firstly identified by us. The observed LSR velocity indicate that almost of the all clouds are located in the Local arm, except two extreme velocity. The mass spectrum of the clouds in the Local arm is best fitted by a power-law index of 1.6.

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허니콤 표면의 마찰계수 특성에 관한 연구 (Part 2 : 마찰계수 급상승현상에 관한 고찰) (The Characteristic of Friction-Factor on Honeycomb Surfaces (Part II : Friction-Factor Jump Phenomenon))

  • 하태웅
    • 대한기계학회논문집
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    • 제18권6호
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    • pp.1439-1447
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    • 1994
  • Test results of friction-factor for the flow of air in a narrow channel lined with various honeycomb geometries show that, generally, the friction-factor is nearly constant or slightly decreases as the Reynolds number(or Mach number) increases, a characteristic common to turbulent flow in pipes. However, in some test geometries this trend is remarkably different. The friction factor dramatically drops and then rises as the Mach number increases. This phenomenon can be characterized as a "friction-factor jump." Further investigations of the acoustic spectrum indicate that the "friction-factor jump" phenomenon is accompanied by an onset of a normal mode resonance excited coherent flow fluctuation structure, which occurs at Reynolds number of the order of $10^4$. New empirical friction-factor model for "friction-factor jump" cases is developed as a function of Mach number and local pressure.ach number and local pressure.

국부 가중평균 질감단위를 이용한 새로운 질감인식 기법 (New Texture Recognition Method Using Local Weighting Averaged Texture Units)

  • 심재창;김기석;이준재;;하영호
    • 전자공학회논문지B
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    • 제31B권4호
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    • pp.129-137
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    • 1994
  • In this paper, a new texture feature extraction method for texture image classification is proposed. The proposed method is a modified texture spectrum method. It uses local weighting averaged texture unit, that is, the neighbor pixels are weithted and averaged in 4-direction and the calculated values are compared with center pixel to find texture units. The proposed method has only 81 texture units and these units are really good features for texture classification. The proposed method is applied to vegetable images and Blodatz album images and compared with several conventional methods for the feature extraction time and the recognition rate.

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분산형 기준모델 적응 제어기 구성에 관한 연구 (On the study of decentralized model reference adaptive controller design)

  • 장석주;김국헌;양흥석
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 16-17 Oct. 1987
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    • pp.193-197
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    • 1987
  • Decentralized model reference adaptive controller is used to control interconnected system. Influences caused by interactions between each subsystem are regarded as unmodeled dynamics or disturbances, thus decentralized adaptive controller is designed using MRAC algorithms which guarantees robustness. To expand the stability regions of over all system and to improve control performances, higher level controller is introduced to adjust the control factors such as filter band, size of deadzone or maximum norm of parameter. Local controllers for each subsystem are realized in real time and higher level controller has an ability of detecting the instability phenomena and adjusts the local controller by analysis of power spectrum or square sum of tracking errors.

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Yeast Flora of the Human Vagina and Effects of Antifungal Agents on its Growth in vitro

  • Haridy, Mamdouh S.A.;Moustafa, A
    • 한국균학회지
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    • 제21권2호
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    • pp.140-145
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    • 1993
  • Yeast strains were isolated from healthy women(36 isolates), infertile women(15 isolates) and women suffering from local morbidity(82 isolates). On the basis of 37 different physiological and morphological characteristics, the isolated 133 yeast strains were assigned to 10 species belonging to 5 genera. Four pathogenic species were identified. They were Candida albicans, Candida parapsilosis, Candida tropicalis and Trichosporon beigelii. Candida albicans was the dominant species, whereas Saccharomyces cerevisiae prevailed among the saprophytic species. The percentage occurrence as well as the pattern of yeast species differed in the diagnostic groups. It was higher in the women suffering from local morbidity than in the healthy and infertile women. Moreover, a wider spectrum of species was isolated from this group. Women with intrauterine contraceptive devices showed the highest percentage of yeast occurrence which reached 50% of those tested. Five different antifungal agents were tested fro their effects on the growth of the isolated yeast species in vitro. Nystatin was the most effective against the isolated yeast species, followed by pyrithion zink and ciclopiroxolamine, whereas micronazole and clotrimazole, showed a lesser effect.

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