• Title/Summary/Keyword: low-predictable.

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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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A Case Study on the Design of Railway Tunnel through section for under OO temple (OO 사찰 하부 터널통과 설계 사례)

  • Kim, Shin;Lee, Sung-Ki;Seo, Hyoung-Chul;Kwag, Jung-Yeol;Cho, Bong-Sik
    • Proceedings of the Korean Geotechical Society Conference
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    • 2006.03a
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    • pp.208-218
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    • 2006
  • It is very important to evaluate predictable problems diversely such as stability of a tunnel and structures when tunnel is inevitably constructed in the area where is adjacent to a structure and low overburden. Double electrified railway design on the third section of Donghae-Nambu line studied in this paper has some problems mentioned above. So more careful works are required before construction. In this study, ground surrounding is composed of faults, fault zone and set back about 13m from a Buddhist temple located on the upper part of the tunnel. From these conditions, this case study presents proper methods considering ground condition, effects of blasting and civil petitions. It is tried to make the tunnel and Buddhist temple stable by analytical technique and analysis of existing cases. And design considering stability of tunnel and adjacent structure during operation is carried out as well. Especially, environmentally friendly railway tunnel which is appropriate to the local condition and surroundings is designed by minimizing noise and vibration that is able to occur during construction and train service. From now on, this study is helpful to better design in the case of tunnel design which has to consider civil petition.

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A STUDY ON THE DIMENSIONAL ACCURACY OF MODELS USING 3-DIMENSIONAL COMPUTER TOMOGRAPHY AND 2 RAPID PROTOTYPING METHODS

  • Cho Lee-Ra;Park Chan-Jin;Park In-Woo
    • The Journal of Korean Academy of Prosthodontics
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    • v.39 no.6
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    • pp.633-640
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    • 2001
  • Statement of problem. Relatively low success rate of root analogue implant system was supposed to be due to the time duration between extraction and implant installation. The use of three-dimensional computer tomography and the reconstruction of objects using rapid prototyping methods would be helpful to shorten this time. Purpose. This aim of this study was to evaluate the application possibility of the 3-dimensional computer tomography and the rapid prototyping to root analogue implants. Material and methods. Ten single rooted teeth were prepared. Width and height of the teeth were measured by the marking points. This was followed by CT scanning, data conversion and rapid prototyping model fabrication. 2 methods were used; fused deposition modelling and stereolithography. Same width and height of this models were measured and compared to the original tooth. Results. Fused deposition modelling showed an enlarged width and reduced height. The stereolithography showed more exact data compared with the fused deposition modelling. Smaller standard deviation were recorded in the stereolithographic method. Overall width error from tooth to rapid prototyping was 7.15% in fused deposition modelling and 0.2% in stereolithography. Overall height showed the tendency of reducing dimensions. Conclusion. From the results of this study, stereolithography seems to be very predictable method of fabricating root analogue implant.

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Surgically assisted rapid palatal expansion with tent screws and a custom-made palatal expander: a case report

  • Park, Kang-Nam;Lee, Chang Youn;Park, In Young;Kim, Jwa Young;Yang, Byoungeun
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.37
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    • pp.11.1-11.5
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    • 2015
  • Rapid palatal expansion(RPE) with the tooth-born appliance is not sufficient to apply to the patients with periodontal problem or insufficient tooth anchorage, and it leads to tipping of the anchorage teeth and increasing teeth mobility and root resorption. To avoid these disadvantages, we present the case using palatal screws and custommade palatal expander. A 23-year-old patient underwent surgically assisted rapid maxillary expansion with the Hyrax expansion using 4 tent screws. The study models were used to measure the pre-/-post surgical width of the anterior and posterior dental arches with a digital sliding caliper. In the result, the custom-made palatal expander with 4 tent screws is suitable for delivering a force to the mid-palatal suture expansion. And it is low cost, small sized and simply applied. The results indicated that maxillary expansion with the custom-made palatal anchorage device is predictable and stable technique without significant complications in patients.

Experimental Studies on Single Phase Flow and Heat Transfer in Microchannels (미세유로의 단상 유동 및 열전달에 대한 실험적 연구)

  • Kim, Byong-Joo;Kim, Geon-Il
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.20 no.12
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    • pp.795-801
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    • 2008
  • An experimental study has been performed on the single phase flow and convective heat transfer in trapezoidal microchannels. The microchannel was about $270{\mu}m$ wide, $800{\mu}m$ deep. and 7 mm long, which might ensure hydrodynamically fully-developed laminar flow at a low Reynolds number. The experiments were conducted with R1l3 and water, with the Reynolds number ranging from approximately 30 to 5000 for friction factor and 30 to 700 for the Nusselt number. Friction factors in laminar are found to be in good agreement with the predictions of existing correlation suggesting that a conventional analysis approach can be employed in predicting flow friction behavior in microchannels. However turbulent friction factors are hardly predictable by the existing correlations. The experimental results show that the Nusselt number is not a constant but increases almost linearly with the Reynolds number even the flow is fully developed (Re < 100). The dependence of the Nusslet number on the Reynolds number is contradictory to the conventional theory. At a Reynolds number greater than 100, the Nusselt number increases slowly with the Reynolds number, where thennally developing flow is responsible for the increase of the Nusselt number with the Reynolds number.

Design of Wired and Wireless linkage Hybrid Sensor Network Model over CATV network (CATV망을 이용한 유무선 연동의 하이브리드 센서 네트워크 모델 설계)

  • Lee, Kyung-Sook;Kim, Hyun-Deok
    • Convergence Security Journal
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    • v.12 no.3
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    • pp.67-73
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    • 2012
  • In this paper, in order to overcome the disadvantage of wireless-based sensor network, a hybrid sensor network using wired and wireless linkage is proposed. Proposed a wired and wireless linkage hybrid sensor network can compensate the defect of poor transmission at the indoor wireless environment, and can be free from interference between a wireless LAN and Bluetooth of the same frequency bandwidth due to an attribute of low-loss transmission at the CATV network. Also, proposed a wired and wireless linkage hybrid sensor network make use of CATV network which is well-built infrastructure, is more efficient to design network, assure a stability and high reliability of the sensor network as providing a stability for an inaccuracy and a predictable transmission link for the existing wireless network.

Formulaic Language Development in Asian Learners of English: A Comparative Study of Phrase-frames in Written and Oral Production

  • Yoon Namkung;Ute Romer
    • Asia Pacific Journal of Corpus Research
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    • v.4 no.2
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    • pp.1-39
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    • 2023
  • Recent research in usage-based Second Language Acquisition has provided new insights into second language (L2) learners' development of formulaic language (Wulff, 2019). The current study examines the use of phrase-frames, which are recurring sequences of words including one or more variable slots (e.g., it is * that), in written and oral production data from Asian learners of English across four proficiency levels (beginner, low-intermediate, high-intermediate, advanced) and native English speakers. The variability, predictability, and discourse functions of the most frequent 4-word phrase-frames from the written essay and spoken dialogue sub-corpora of the International Corpus Network of Asian Learners of English (ICNALE) were analyzed and then compared across groups and modes. The results revealed that while learners' phrase-frames in writing became more variable and unpredictable as proficiency increased, no clear developmental patterns were found in speaking, although all groups used more fixed and predictable phrase-frames than the reference group. Further, no developmental trajectories in the functions of the most frequent phrase-frames were found in both modes. Additionally, lower-level learners and the reference group used more variable phrase-frames in speaking, whereas advanced-level learners showed more variability in writing. This study contributes to a better understanding of the development of L2 phraseological competence.

Effect of humidity on postmortem changes in rats

  • Seroc Oh;Byeongwoo Ahn;Beom Jun Lee;Sang-Yoon Nam
    • Journal of Veterinary Science
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    • v.25 no.3
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    • pp.24.1-24.9
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    • 2024
  • Importance: In veterinary forensic science, accurately determining the postmortem interval (PMI) is crucial for identifying the causes of animal deaths. Autolysis, a significant postmortem process, influences PMI estimation, but its relationship with humidity is not well understood. Objective: This study aimed to improve the accuracy of PMI estimates in veterinary forensic cases by looking into how different humidity levels affect autolysis in different organs of rats. Methods: The study involved 38 male rats, examining histopathological changes in their heart, liver, and pancreas. These organs were subjected to controlled humidity levels (20%, 55%, and 80%) at a constant 22℃. Tissue samples were collected at several intervals (0 h, 12 h, 24 h, 3 days, and 8 days) for comprehensive analysis. Results: Distinct autolytic characteristics in animal organs emerged under varying humidity conditions. The low-humidity environment rapidly activated autolysis more than the high-humidity environment. In addition, it was found that lower humidity caused nuclear pyknosis, cytoplasmic disintegration, and myofiber interruption. The liver, in particular, showed portal triad aggregation and hepatocyte individuation. The pancreas experienced cell fragmentation and an enlarged intracellular space. High humidity also caused the loss of striations in cardiac tissues, and the liver showed vacuolation. Under these conditions, the pancreas changed eosinophilic secretory granules. Conclusions and Relevance: The study successfully established a clear connection between the autolytic process in PMIs and relative humidity. These findings are significant for developing a more accurate and predictable method for PMI estimation in the field of veterinary forensic science.

Predictability effects on speech perception in noise (SPIN) in Korean (한국어 소음속말인지에 나타나는 예측성 효과)

  • Lee, Sun-Young
    • Korean Journal of Cognitive Science
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    • v.27 no.1
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    • pp.129-157
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    • 2016
  • This study investigates speech perception in noise (SPIN) in Korean. A new type of Korean SPIN test was developed by adopting a similar format to the English SPIN test. The predictability effects, noise effects and their interactions were examined in order to verify the previous findings based on English. The data from 14 Korean adults collected with this new type of Korean SPIN test confirmed the previous findings: first, the participants' overall performance was better in low noise conditions than in high noise conditions. Secondly, there was a tendency for highly predictable words to be more accurately perceived than less predictable words especially in high noise conditions. The results were interpreted in such a way that the listeners actively used both types of information: acoustic information and contextual information in speech perception. When the acoustic property of the speech sound was degraded with noise, the listeners took advantage of the linguistic contextual information in their processing of the speech sound. The findings of this study conform to those of the previous studies based on the English SPIN test. In addition, a possible effect of the frequency of target word was also found, calling for further investigation in this field of research in Korean. Implications of the results were also discussed. (Cyber Hankuk University of Foreign Studies)

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Two Cases Report of Bronchial Carcinoid Tumors (기관지 유암종 2례)

  • Choi, Kyo-Won;Suh, Jeong-Ill;Kim, Sung-Suk;Chung, Jin-Hong;Lee, Kwan-Ho;Lee, Hyun-Woo;Lee, Dong-Hyup;Lee, Jung-Cheul;Han, Sung-Sae
    • Journal of Yeungnam Medical Science
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    • v.10 no.2
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    • pp.525-536
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    • 1993
  • Bronchial carcinoid tumor was a low grade malignant and it was regarded as predictable clinical course and good survivality after surgical resection. But despite of its low grade malignant potentiality, bronchial carcinoid tumor was clearly capable of metastasizing and causing death. We present 2 cases of bronchial carcinoid tumors. One of them was typical carcinoid tumor in 44 year-old female and another was atypical carcinoid tumor in 53 year-old male patient. Currative therapeutic procedure was performed by lobectomy and wedge resection.

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