• Title/Summary/Keyword: Pre-emphasis

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The Multiethnic Cohort Study of Diet and Cancer: Design and Early Findings

  • Kolonel, Laurence N.
    • Nutritional Sciences
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    • v.7 no.1
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    • pp.53-58
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    • 2004
  • The Multiethnic Cohort Study was designed to study prospectively the relationship of diet and other lifestyle factors to the risk of cancer. The cohort was established in 1993-1996 in Hawaii and California (primarily Los Angeles) and included a representative sample of more than 215,000 men and women primarily from five different ethnic groups: Japanese, whites, Native Hawaiians, Latinos, and African- Americans. Because of the emphasis on diet, great attention was paid to developing and pre-testing a self-administered quantitative food frequency questionnaire that would adequately assess food and nutrient intakes in these groups. An extensive food composition database was also created for the study. In addition, during data collection, a calibration study was conducted that makes possible adjustment for measurement error in nutrient intakes and valid comparison of intakes across the several ethnic groups. At the present time, blood and urine specimens are being collected from cohort participants and should yield a biorepository of more than 80,000 subjects. Baseline data indicate that the cohort is well representative of the general population of Hawaii and California, so that results can be generalized. These data also show a wide range in dietary intakes and in other lifestyle variables that should facilitate the testing of etiologic hypotheses.

Performance of Shotcrete Lining due to Tunneling and Groundwater Interaction Using a 3D Stress-pore Pressure Coupled Analysis (응력-간극수압 3차원 연계해석을 이용한 터널시공과 지하수의 상호작용으로 인한 라이닝 거동특성 연구)

  • Yoo, Chung-Sik;Kim, Sun-Bin
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.03a
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    • pp.465-474
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    • 2005
  • This paper presents the interaction effect between tunneling and groundwater on tunnel behavior. A parametric study is then conducted on the various tunneling situations frequently encountered in Seoul area using a 3D stress-pore pressure coupled finite-element model with emphasis on the effects of ground and lining permeabilities. It is shown that the ground and lining responses are significantly influenced by the relative permeability between the ground and the lining, and that the circumferential pre-grouting is effective in minimizing the tunnelling and groundwater interaction.

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On Speech Input with Microphone Array using the variable coefficient Pre-emphasis (가변계수 프리엠퍼시스를 이용한 마이크어레이 음성입력에 관한 연구)

  • Jo Wangrae;Bae Myungjin
    • Proceedings of the Acoustical Society of Korea Conference
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    • autumn
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    • pp.65-68
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    • 2001
  • 현재 음성인식기는 다채널의 음성입력방식을 사용하고 있는 추세이다. 이런 방법으로 음성인식기를 사용할 때에 자동적으로 음성을 검출하는 음성입력방식은 발성자와 마이크간의 거리에 따라 발성음성, 반사음성과 잡음이 입력된 경우에 원 음성의 고차포만트 성분에 왜곡이 발생하게 된다 이러한 문제점을 개선하기 위하여 본 논문에서는 고주파영역의 특성을 강조시킬 수 있는 프리엠퍼시스를 이용하여 더욱 더 정확한 음성입력 방법을 제안한다. 제안한 방법은 원음과 유사한 합성입력음을 얻었고, 또한 기존의 시간영역 법 보다 더 높은 SNR을 얻을 수 있다는 것을 알 수가 있다.

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Examination of Prospective Teachers' Perceptions on Mathematical Concepts and Their Potential Teaching Strategies

  • Lee, Ji-Eun
    • Research in Mathematical Education
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    • v.18 no.1
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    • pp.55-74
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    • 2014
  • This study examined the potential teaching strategies of prospective elementary teachers and their perceptions of the procedural/conceptual nature of examples. Fifty-four prospective teachers participated in this study, engaging in two-phase tasks. Analysis of data indicated that: (a) Overall, the participants' perceptions were geared toward putting emphasis on conceptual understanding rather than procedural understanding; but (b) Generally, procedure-oriented strategies were more frequently incorporated in participants' potential teaching plans. This implied that participants' preconceived ideas regarding math examples were not always reliable indicators of their potential teaching strategies. Implications and suggestions for mathematics teacher preparation are discussed.

Endoscopic Resection for Early Gastric Cancer beyond Absolute Indication with Emphasis on Controversial Issues

  • Min, Yang Won;Lee, Jun Haeng
    • Journal of Gastric Cancer
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    • v.14 no.1
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    • pp.7-14
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    • 2014
  • Endoscopic resection is the established treatment for early gastric cancer in selected patients with negligible risk of lymph node metastasis ('absolute indication'). Based on clinical observations and large pathological databases, expanding indications for endoscopic resection beyond absolute indication has been tried in Japan and Korea. However, controversies exist regarding the safety of treating early gastric cancer beyond absolute indication in terms of pathological evaluation of the resected specimen, definition of expanded indication, discrepancy between pre-endoscopic resection and post-endoscopic resection diagnoses of gastric neoplasm, and the best strategy for cases with non-curative resection. In this brief review, current evidence and clinical experience regarding issues of endoscopic resection beyond absolute indication will be summarized.

Science Teacher Education in Hong Kong

  • Yip, Din-Yan
    • Journal of The Korean Association For Science Education
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    • v.22 no.5
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    • pp.1044-1070
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    • 2002
  • Initial science teacher education in Hong Kong is provided by the Post-graduate Diploma in Education Programme (PGDE) for both pre-service and in-service secondary school teachers. This programme includes a balanced treatment of subject curriculum and teaching in science, general pedagogical knowledge and skills, educational psychology and school administration. The science courses in this programme also have some units that equip science teachers with the knowledge and skills that are essential for teaching a science curriculum that emphasises conceptual change and understanding of the nature and methods of science. This emphasis is illustrated by two studies: (1) Developing a conceptual change model of instruction in Biology teachers, and (2) Constructing understanding of the nature and methods of science.

A Study on the Estimation of Glottal Spectrum Slope Using the LSP (Line Spectrum Pairs) (LSP를 이용한 성문 스펙트럼 기울기 추정에 관한 연구)

  • Min, So-Yeon;Jang, Kyung-A
    • Speech Sciences
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    • v.12 no.4
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    • pp.43-52
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    • 2005
  • The common form of pre-emphasis filter is $H(z)\;=\;1\;- az^{-1}$, where a typically lies between 0.9 and 1.0 in voiced signal. Also, this value reflects the degree of filter and equals R(1)/R(0) in Auto-correlation method. This paper proposes a new flattening algorithm to compensate the weaked high frequency components that occur by vocal cord characteristic. We used interval information of LSP to estimate formant frequency. After obtaining the value of slope and inverse slope using linear interpolation among formant frequency, flattening process is followed. Experimental results show that the proposed algorithm flattened the weaked high frequency components effectively. That is, we could improve the flattened characteristics by using interval information of LSP as flattening factor at the process that compensates weaked high frequency components.

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Adaptive Techniques for Joint Optimization of XTC and DFE Loop Gain in High-Speed I/O

  • Oh, Taehyoun;Harjani, Ramesh
    • ETRI Journal
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    • v.37 no.5
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    • pp.906-916
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    • 2015
  • High-speed I/O channels require adaptive techniques to optimize the settings for filter tap weights at decision feedback equalization (DFE) read channels to compensate for channel inter-symbol interference (ISI) and crosstalk from multiple adjacent channels. Both ISI and crosstalk tend to vary with channel length, process, and temperature variations. Individually optimizing parameters such as those just mentioned leads to suboptimal solutions. We propose a joint optimization technique for crosstalk cancellation (XTC) at DFE to compensate for both ISI and XTC in high-speed I/O channels. The technique is used to compensate for between 15.7 dB and 19.7 dB of channel loss combined with a variety of crosstalk strengths from $60mV_{p-p}$ to $180mV_{p-p}$ adaptively, where the transmit non-return-to-zero signal amplitude is a constant $500mV_{p-p}$.

A Study on Extract of Vocal Tract Characteristic after Concealing the Vocal Cord Property (성문특성이 제거된 성도특성 추출에 관한 연구)

  • Lim, Ji-Sun
    • Proceedings of the KAIS Fall Conference
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    • 2010.05a
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    • pp.253-256
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    • 2010
  • Since the amplitude of voiced fall off at about -20dB/decade, dynamic range is often compressed prior to spectral analysis so that details at weak, high frequencies may be visible. Preemphasizing the speech, either by differentiating the analog speech $s_a$(t) prior to A/D conversion or by differencing the discrete-time s(n)=$s_a$(nT), compensating for falloff at high frequencies. The most common form of preemphasis is y(n)=s(n)-As(n-1), where A typically lies between 0.9 and 1.0 and reflects the degree of pre-emphasis. In this paper, we proposed that A is adjusted at each time by measuring the slope of envelope in frequency domain.

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Numerical investigation of mechanical properties of nanowires: a review

  • Gu, Y.T.;Zhan, H.F.;Xu, Xu
    • Interaction and multiscale mechanics
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    • v.5 no.2
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    • pp.115-129
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    • 2012
  • Nanowires (NWs) have attracted intensive researches owing to the broad applications that arise from their remarkable properties. Over the last decade, immense numerical studies have been conducted for the numerical investigation of mechanical properties of NWs. Among these numerical simulations, the molecular dynamics (MD) plays a key role. Herein we present a brief review on the current state of the MD investigation of nanowires. Emphasis will be placed on the FCC metal NWs, especially the Cu NWs. MD investigations of perfect NWs' mechanical properties under different deformation conditions including tension, compression, torsion and bending are firstly revisited. Following in succession, the studies for defected NWs including the defects of twin boundaries (TBs) and pre-existing defects are discussed. The different deformation mechanism incurred by the presentation of defects is explored and discussed. This review reveals that the numerical simulation is an important tool to investigate the properties of NWs. However, the substantial gaps between the experimental measurements and MD results suggest the urgent need of multi-scale simulation technique.