• Title/Summary/Keyword: background response

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The Effect of Background Grey Levels on the Visual Perception of Displayed Image on CRT Monitor (CRT 모니터의 배경계조도가 영상의 시각인식에 미치는 영향)

  • 김종효;박광석
    • Journal of Biomedical Engineering Research
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    • v.14 no.1
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    • pp.63-72
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    • 1993
  • In this paper, the effect of background grey levels on the visual perception of target image displayed on CRT monitor has been investigated. The purpose of this study is to investigate the efficacy of CRT monitor as a display medium of image Information especially in medical imaging field. Tllree sets of experiments have been performed in this study : the first was to measure the luminance response of CRT monitor and to find the best fitting equation, and the second was the psychophysical experiment measuring the threshold grey level differences between the target image and the background required for visual discrimination (or various background grey levels, and the third was to develop a visual model that is predictable of the threshold grey level difference measured in the psychophysical experiment. The result of psycophysical experiment shows that the visual perception performance is significantly degraded in the range of grey levels lower than 50, which is turned out due to she low luminance change of CRT monitor in this range while human eye has been adapted lo relatively bright ambient illumination. And it Is also shown in the simulation study using the developed visual model that the dominant factor degrading the visual performance is the reflected light from the monitor surface by ambient light in general illumination condition.

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Functional Changes of Spinal Sensory Neurons Following Gray Matter Degeneration

  • Park, Sah-Hoon;Park, Jong-Seong;Jeong, Han-Seong
    • The Korean Journal of Physiology
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    • v.30 no.2
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    • pp.289-297
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    • 1996
  • Excitatory amino acids (EAA) are thought to play an important role in producing cell death associated with ischemic and traumatic spinal cord injury. The present study was carried out to determine if the response characteristics of spinal sensory neurons in segments adjacent to degeneration sites induced by EAA are altered following these morphological changes. Intraspinal injections of quisqualic acid (QA) produced neuronal degeneration and spinal cavitation of gray matter. The severity of lesions was significantly attenuated by pretreatment with a non-NMDA antagonist NBQX. In extracellular single unit recordings, dorsal horn neurons in QA injected animal showed the increased mechanosensitivity, which included a shift to the left in the stimulus-response relationship, an increased background activity and an increase in the duration of after-discharge responses. Neuronal responses, especially the C-fiber response, to suprathreshold electrical stimulation of sciatic nerve also increased in most cases. These results suggest that altered functional states of neurons may be responsible for sensory abnormalities, e.g. allodynia and hyperalgesia, associated with syringomyolia and spinal cord injury.

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Vocabulary Size of Korean EFL University Learners: Using an Item Response Theory Model

  • Lee, Yongsang;Chon, Yuah V.;Shin, Dongkwang
    • English Language & Literature Teaching
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    • v.18 no.1
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    • pp.171-195
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    • 2012
  • While noticing that there is insufficient interest in the assessment of EFL learners' vocabulary levels or sizes, the researchers developed two tests identical in form (Forms A and B) to assess the lexical knowledge of Korean university learners at the $1^{st}{\sim}10^{th}$ 1,000 word bands by adapting a pre-established vocabulary levels test (VLT). Of equal concern was to investigate if the VLT was equally a valid and reliable instrument to be used on measuring the lexical knowledge of EFL learners. The participants were 804 university freshmen enrolled in a General Education English Course from four different colleges. The learners were asked to respond to either Form A or B. While scores generally fell towards the lower frequency bands, multiple regression found the Korean College Scholastic Ability Test (CSAT) to be a significant variable for predicting the learners' vocabulary sizes. From a methodological perspective, however, noticeable differences between Forms A and B could be found with item response theory analysis. The findings of the study provide suggestions on how future VLT for testing EFL learners may have to be redesigned.

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The Parametric Sensitivity Analyses of linear System Relative to the Characteristic Ratios of Coefficient(II) : K-Polynomial Case (계수의 특성비에 대한 선형계의 파라미터적 감도해석(II) : K-다항식의 경우)

  • 김영철;김근식
    • Journal of Institute of Control, Robotics and Systems
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    • v.10 no.4
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    • pp.295-303
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    • 2004
  • Previously it has been shown that the all pole systems resulting good time responses can be characterized by so called K-polynomial. The polynomial is defined in terms of the principal characteristic ratio $\alpha_1$ and the generalized time constant $\tau$ . In this paper, Part II presents several sensitivity analyses of such systems with respect to $\alpha_1$ and $\tau$ changes. We first deal with the root sensitivity to the perturbation of $\alpha_1$ . By way of determining the unnormalized function sensitivity, both time response sensitivity and frequency response sensitivity are derived. Finally, the root sensitivity relative to $\tau$ change is also analyzed. These results provide some useful insight and background theory when we select of and l to compose a reference model of which denominator is a K-polynomial, which is illustrated by examples.

DDAM Shock Analysis for Equipment Systems of Ships (함정 장비시스템의 내충격해석을 위한 동적설계해석법 (DDAM) 응용)

  • Lee, J.M.;Lee, S.M.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.06a
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    • pp.1180-1184
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    • 2000
  • The dynamic design analysis method (DDAM) to analyze and evaluate shock response of the equipment system mounted in ships are discussed. Theoretical background of the DDAM based on the general shock response analysis was introduced. Spectrum dip effect between the equipment system and supporting structure was specially focused being peculiar to general shock response analysis. Actual shock design values used in the DDAM were reviewed in their category, general trend and establishing process. Aspects of DDAM analysis using MSC/NASTRAN were shortened. As a conclusion DDAM is regarded as a reasonable way of analysis for the onboard equipment system due to the underwater shock.

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A Pooled Study on Combination of Gemcitabine and Nedaplatin for Treating Patients with Non-small Cell Lung Cancer

  • Yang, Song
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.14
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    • pp.5963-5966
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    • 2015
  • Background: This analysis was conducted to evaluate the efficacy and safety of a combination of gemcitabine and nedaplatin in treating patients with non-small cell lung cancer. Methods: Clinical studies evaluating the efficacy and safety of a combination of gemcitabine and nedaplatin with attention to response and safety for patients with non-small cell lung cancer were identified using a predefined search strategy. Pooled response rates for gemcitabine and nedaplatin were calculated. Results: In gemcitabine and nedaplatin based regimens, 4 clinical studies including 112 patients with non-small cell lung cancer were considered eligible for inclusion. The pooled analysis suggested that the pooled reponse rate was 40.2% (45/112). Main side effects included grade 3-4 neutropenia, thrombocytopenia, and anemia. Grade 3-4 nonhematological toxicity included nausea and vomiting, diarrhea, and hepatic dysfunction. There were no treatment-related deaths. Conclusion: This evidence based analysis suggests that the combination of gemcitabine and nedaplatin is associated with good response rate and accepted toxicity for treating patients with non-small cell lung cancer.

Visual Tracking using Weighted Discriminative Correlation Filter

  • Song, Tae-Eun;Jang, Kyung-Hyun
    • Journal of the Korea Society of Computer and Information
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    • v.21 no.11
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    • pp.49-57
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    • 2016
  • In this paper, we propose the novel tracking method which uses the weighted discriminative correlation filter (DCF). We also propose the PSPR instead of conventional PSR as tracker performance evaluation method. The proposed tracking method uses multiple DCF to estimates the target position. In addition, our proposed method reflects more weights on the correlation response of the tracker which is expected to have more performance using PSPR. While existing multi-DCF-based tracker calculates the final correlation response by directly summing correlation responses from each tracker, the proposed method acquires the final correlation response by weighted combining of correlation responses from the selected trackers robust to given environment. Accordingly, the proposed method can provide high performance tracking in various and complex background compared to multi-DCF based tracker. Through a series of tracking experiments for various video data, the presented method showed better performance than a single feature-based tracker and also than a multi-DCF based tracker.

A Study on Designing Mobile Phone Display in Consideration of Elder People's Optical Characteristics and Preferences: Using Conjoint Analysis and Response Surface Method (장년층의 시각적 특성과 선호도를 고려한 휴대폰의 디스플레이 설계에 관한 연구: 컨조인트 분석과 반응표면분석을 활용하여)

  • Lee Sung-Hoon;Shin Yong-Sik;Park Yong-Gil
    • Journal of The Institute of Information and Telecommunication Facilities Engineering
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    • v.4 no.1
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    • pp.23-29
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    • 2005
  • This study is about designing mobile phone display in consideration of elder people's preferences by reason of their optical weakness. The research is closely connected with designing user-friendly interface by considering user characteristics. The criteria for first experiment are font sizes, font types, line spacing and background colors. With the experiment result, relative importance of each attribute and subjective preference are investigated by conjoint analysis. Secondly, an optimal display design for elder people is presented by response surface method on the basis of the result of conjoint analysis, other statistical analyses, and user interviews.

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Trans-arterial Chemo-Embolization in Treating Elderly Patients with Hepatocellular Carcinoma

  • Zhang, Jian-Feng;Liu, Jun-Mao;Zhang, Nin;Du, Chao;Zheng, Qin
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.16
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    • pp.7201-7204
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    • 2015
  • Background: This analysis was conducted to evaluate the efficacy and safety of Trans-arterial Chemo-Embolization (TACE) in treating Elderly patients with Hepatocellular Carcinoma (EHPC). Methods: Clinical studies evaluating the efficacy and safety of TACE on response and safety for patients with EHPC were identified by using a predefined search strategy. Pooled response rate of treatment were calculated. Results: In TACE based regimen, clinical studies which including patients with EHPC were considered eligible for the evaluation of response. And, in these TACE based treatments, pooled analysis suggested that, in all 288 patients whose response could be assessed, the pooled reponse rate was 29.5%(85/288) in TACE based treatment. The most commonly encountered TACE-related morbidity was liver function impairment. No grade III or IV renal or liver toxicity were observed. No treatment related death occurred in EHPC patients with TACE based treatments. Conclusion: This evidence based analysis suggests that TACE based treatments are associated with mild response rate and accepted toxicities for treating patients with EHPC.

Wind-Induced Motion of Tall Buildings: Designing for Occupant Comfort

  • Burton, M.D.;Kwok, K.C.S.;Abdelrazaq, A.
    • International Journal of High-Rise Buildings
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    • v.4 no.1
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    • pp.1-8
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    • 2015
  • A team of researchers and practitioners were recently assembled to prepare a monograph on "Wind-Induced Motion of Tall Buildings: Designing for Habitability". This monograph presents a state-of-the-art report of occupant response to wind-induced building motion and acceptability criteria for wind-excited tall buildings. It provides background information on a range of pertinent subjects, including: ${\bullet}$ Physiological, psychological and behavioural traits of occupant response to wind-induced building motion; ${\bullet}$ A summary of investigations and findings of human response to real and simulated building motions based on field studies and motion simulator experiments; ${\bullet}$ A review of serviceability criteria to assess the acceptability of wind-induced building motion adopted by international and country-based standards organizations; ${\bullet}$ General acceptance guidelines of occupant response to wind-induced building motion based on peak acceleration thresholds; and ${\bullet}$ Mitigation strategies to reduce wind-induced building motion through structural optimization, aerodynamic treatment and vibration dissipation/absorption. This monograph is to be published by the American Society of Civil Engineers (ASCE) and equips building owners and tall building design professionals with a better understanding of the complex nature of occupant response to and acceptability of wind-induced building motion. This paper is a brief summary of the works reported in the monograph.