• Title/Summary/Keyword: Critical depth

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3D Visual Attention Model and its Application to No-reference Stereoscopic Video Quality Assessment (3차원 시각 주의 모델과 이를 이용한 무참조 스테레오스코픽 비디오 화질 측정 방법)

  • Kim, Donghyun;Sohn, Kwanghoon
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.4
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    • pp.110-122
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    • 2014
  • As multimedia technologies develop, three-dimensional (3D) technologies are attracting increasing attention from researchers. In particular, video quality assessment (VQA) has become a critical issue in stereoscopic image/video processing applications. Furthermore, a human visual system (HVS) could play an important role in the measurement of stereoscopic video quality, yet existing VQA methods have done little to develop a HVS for stereoscopic video. We seek to amend this by proposing a 3D visual attention (3DVA) model which simulates the HVS for stereoscopic video by combining multiple perceptual stimuli such as depth, motion, color, intensity, and orientation contrast. We utilize this 3DVA model for pooling on significant regions of very poor video quality, and we propose no-reference (NR) stereoscopic VQA (SVQA) method. We validated the proposed SVQA method using subjective test scores from our results and those reported by others. Our approach yields high correlation with the measured mean opinion score (MOS) as well as consistent performance in asymmetric coding conditions. Additionally, the 3DVA model is used to extract information for the region-of-interest (ROI). Subjective evaluations of the extracted ROI indicate that the 3DVA-based ROI extraction outperforms the other compared extraction methods using spatial or/and temporal terms.

Environmental Characteristics of the Diatom in the Trench Sediments Around Bangudae Petroglyphs, Ulsan (울산 반구대 암각화 인근 트렌치 퇴적물 내 규조의 환경 특성)

  • Bak, Young-Suk;Ryu, Choon Kil;Cho, Mi-Soon
    • Journal of the Korean earth science society
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    • v.37 no.1
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    • pp.11-20
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    • 2016
  • Diatoms were studied from the trench sediments around Bangudae petroglyphs in order to better understand the depositional environment before and after the construction of Sayeon dam in Ulsan. There were no diatoms produced from the sediments before the dam construction while the diatoms were produced from the sediments (depth of trench 228 cm) after the construction of the dam. Seventy-five species of diatoms of 27 genera were identified in the trench sediments. The number of diatom valves per gram of dry sediment ranged from $0.2-5.8{\times}10^5g^{-1}$. Four diatom assemblage zones were identified according to the frequency of critical taxa as follows: assemblage zone I, from 228 to 150 cm; assemblage zone II, from 150 to 122 cm; assemblage zone III, from 122 to 62 cm; and assemblage zone IV, from 62 to 0 cm. In addition, based on the environmental indicator species, an analysis was carried out to measure eutrophication, acidity and $Cl^-$ value. Results of the eutrophication and $Cl^-$ values were as follows. Based on the lower 74 cm horizons, the degree of eutrophication middle-high to $Cl^-$ values were lower, upper horizons appeared to eutrophication in the low, and $Cl^-$ values were high. Acidification from low horizons of 122 cm showed a neutral-alkaline degree whereas it exhibited acid in the upper part. In particular, regarding nutrients (TP and TN), the index taxa showed a higher TP value at 175 cm while higher TN value at 62 cm.

An Explorative Study on Discourses of Adequate Validity Criterion in Qualitative Research (질적 연구의 타당도 담론에 관한 탐색적 연구 - 주관성과 사회성의 긴장을 중심으로 -)

  • Kim, Kyung-Hee;Kim, Gi-Duk;Park, Ji-Young
    • Korean Journal of Social Welfare
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    • v.63 no.2
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    • pp.155-177
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    • 2011
  • This paper attempts to explore the universal foundation on which the discourses on the validity criteria in qualitative research should be based, and further discuss in depth the scope and direction of an adequate validity criterion in qualitative research by critical examination of previous discourses. To establish the foundation for qualitative research, first of all, the concept of quality and qualitative paradigm were examined in terms of ontology and epistemology, especially focused on the works carried out by Aristotle, Kenneth and Boyd. Secondly, the earlier studies on the validity of qualitative research were critically reviewed in terms of the theoretical findings on the concept of quality and qualitative paradigm. The major results include the following: First, the true content of quality is defined as the 'what-ness' or essence of things perceived by subjects, and qualitative paradigm as adequate framework for qualitative research is comprised of two intrinsic modes: one is the mode of awareness and the other is that of expression. Second, qualitative researchers are able to reach to the higher level of validity by considering not only the subjectivity and the originality but also the sociality in drawing a conclusion through qualitative perception. Third, the trend of previous validity discourses can be firmly summarized as the effort to overcome the effect of quantitative research and acquire the true identity for qualitative research, which is subjectivity, and as the quest to compromise the tension between subjectivity and sociality. Finally, based on the findings, several research topics are suggested. For example, the more attention should be paid to the area of the expression of qualitative awareness as a way of overcome the tension between subjectivity and publicness.

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A Discourse on the Issues and Problems of Kindergartens Attached to Elementary Schools: A Perspective of the Directors of the Kindergartens (초등학교 병설유치원 원장이 바라본 초등학교 병설유치원의 쟁점과 과제에 관한 담론)

  • Kim, An Na
    • Korean Journal of Childcare and Education
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    • v.8 no.5
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    • pp.203-229
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    • 2012
  • This study tries to provide basic data that can be useful in suggesting the direction of kindergartens attached to elementary schools, by examining the issues in such kindergartens and the ways to develop them for the future. To do this, I surveyed seven participants, who are currently directors in the kindergartens attached to the elementary schools, by in-depth interviewing. As a result, I found the main issue involves the administrators' lack of expertise about the education of preschoolers. Thus, I suggest that there should be more opportunities to retrain the affiliated principals or directors to better understand the education of preschoolers or the related instructors. Second, I concluded that another critical issue involves the poor administrative and financial system in the current kindergartens attached to the elementary schools. To solve this, I suggest that the government and the local education offices should actively support them with a the solid administrative and financial system. Finally, considering the complaints that the current teachers in those kindergartens are being isolated from the greater society, I suggest that there should be specific solutions to construct the cooperative systems related to scholarships and consulting that help the teachers develop their expertise in educating preschoolers.

On Analyzing the "Hell-Chosun" Phenomenon in Contemporary South Korea Through a Textual Analysis of Media Representation ('헬조선 현상'의 특징과 함의를 분석하기 보수언론과 진보언론 간의 재현작용에 대한 텍스트 분석을 중심으로)

  • Kim, Aerin;Im, Hye Bin;Chang, Hansl;Park, Juhwa;Ki, Seungyeon;Jeong, Yoon Jung;Kim, Sujin;Shin, Juyeong;Lee, Keehyeung
    • Korean journal of communication and information
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    • v.80
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    • pp.40-114
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    • 2016
  • This work critically explores the so-called "Hell-Chosun" phenomenon which has gained much attention and responses in contemporary South Korea. The younger generation came to coin and utilize this new linguistic expression as well as poignant parody as a way of releasing their anger, cynicism, and frustration in the context of the omnipresent fierce competitions, deepening social instability, and job-related shrinking possibilities. The 'Hell-Chosun' phenomenon can be considered as a much complicated manifestation of the structures of feeling for the part of many younger generation South Koreans. This paper especially examines the varying representation of this phenomenon by established dailies through an in-depth textual analysis of newspaper articles, opinion pieces and reviews, as well as special issues. In doing so, this work examines the multiple implications of this particular socio-cultural phenomenon in a detailed and critical fashion.

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Dynamic Behavior of the Prestressed Composite Girder by Modal Tests and Moving Train Analysis (프리스트레스트 강합성 거더의 모달테스트 및 이동 열차하중 해석에 의한 동적거동)

  • Kim, Sung Il;Lee, Pil Goo;Lee, Jung Whee;Yeo, In Ho
    • Journal of Korean Society of Steel Construction
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    • v.18 no.6
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    • pp.793-804
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    • 2006
  • Various PSC and steel-concrete composite railway bridges are being developed for short-medium spans with structural and economic efficiency. According to the design concept, the prestressed composite girder bridge has the advantages of being lightweight and having low girder depth, with the capacity for long spans. However, the dynamic behavior under a passing train is one of the critical issues concerning these railway bridges designed with more flexibility. Therefore, it is very important to evaluate the modal parameters before performing dynamic analyses. In this paper, real-scale prestressed composite girders were fabricated as a test model and modal testing was carried out to evaluate modal parameters including natural frequency and modal damping ratio. During the modal testing, a digitally controlled vibration exciter as well as an impact hammer was applied to obtain frequency-response functions, and the modal parameters were also evaluated after the fracture of test models. With application of reliable properties from modal tests, the estimation of dynamic performances of prestressed composite girder railway bridges can be obtained from various parametric studies on dynamic behavior under the passage of a moving train.

Effect of Zn/NaCl ratios on the charge/discharge performance in Na-ZnCl2 battery (Na-ZnCl2 전지에서 Zn/NaCl 비율이 충방전 특성에 미치는 영향)

  • Kim, Heon-Tae;Kim, Seong-In;Choi, Hee-Lack;Park, Won-Il;Kim, Chang-Sam
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.25 no.2
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    • pp.74-79
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    • 2015
  • $Na-ZnCl_2$ battery, which operates as the same mechanism of $Na-NiCl_2$ battery using solid-electrolyte, is able to reduce its material cost by 40 % comparing to the $Na-NiCl_2$ battery. It has been known that the $Na-ZnCl_2$ battery produces $Na_2ZnCl_4$ as an intermediate phase during charge/discharge process. Therefore, the redox process is divided into four steps having the voltage range of 1.92~2.13 V. However, effects of the critical factors such as the composition of cathode materials, depth of charge and discharge, and additives have not been reported yet. We examined the effect of the Zn/NaCl ratios and revealed that its optimum ratio was in the range of 1.3~1.7.

The Relationship among Media use, Political cynicism, Voting Behavior in 2012 General Elections (2012 국회의원 총선에서 나타난 미디어 이용, 정치 냉소주의, 투표 참여 간의 관계에 관한 연구)

  • Kwon, Hyok-Nam
    • Korean journal of communication and information
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    • v.60
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    • pp.28-51
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    • 2012
  • This study explored the influence of media use on the audiences' intention to vote as well as their political cynicism in 2012 General elections. I offered three research questions: Research Question 1: What is the impact of media use on the political cynicism? Research Question 2: What are the impact of political intersest, political knowledge, media malaise, political efficacy on the political cynicism? Research Question 3: What is the impact of political cynicism on vote behavior? This study analysed survey data. Based on the results of hierarchial regression analysis and path analysis(AMOS), Internet news use was found to have a significant impact on the political cynicism. But the use of newspaper, TV news were not related to political cynicism. The political efficacy decreased political cynicism effectively, The findings from this study indicate that the relationship between media use and political cynicism is contingent on many factors and that cynicism has a negligible impact on citizen participation. This study also found that persons higher in efficacy were less cynical than low in efficacy. This suggest that cynicism is not always bad thing, that it may in fact be an indication of "an interested and critical citizenry". In conclusion this study showed that we need more in-depth analyses on the relationships among attention to media use, political cynicism and voting behavior to activate political participation.

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Opportunities and Challenges for Multi-Level-Stakeholder Participation in Community-Based Ecotourism Development: The Case of the Boabeng-Fiema Monkey Sanctuary, Ghana (지역사회 기반 생태관광 개발에서 다양한 이해 관계자들의 참여 기회와 도전: 가나 Boabeng-Fiema 원숭이 보호구역 사례를 중심으로)

  • Owusu, Victor;Boafo, Yaw Agyeman
    • Journal of the Economic Geographical Society of Korea
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    • v.21 no.1
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    • pp.53-68
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    • 2018
  • Community-based ecotourism (CBE), if well-developed can be a practical approach for promoting socio-economic well-being and sustaining ecological resources. The growth and its development worldwide especially in developing economies is a welcome development. The study aimed at assessing the Boabeng-Fiema Monkey Sanctuary in Ghana, as an example of traditional conservation system of management that has ensured greater community participation, equity, inclusiveness, and multi-level stakeholder partnership. In-depth interviews with key informants and documentary analysis of relevant peer reviewed and grey literature were the main qualitative data collection used. Results revealed that majority of the interviewees support and value the current system of traditional management. The enforcement of rules and regulations and other cultural and religious practices were discussed by key informants. Opportunities for multiple livelihood strategies as a result of the CBE is seen as critical for increasing local's acceptance and participation. The remarkable growth of the sanctuary, as well as the increase in human population, has created a shortage of land for domestic and other commercial purposes which is identified as posing a major challenge to the sustenance of the sanctuary. The study recommends diversification of livelihood opportunities presented by the presence of the sanctuary like the introduction of homestay concept, craft making- wood carving, painting, artisan shops.

An Evaluation of Soil-Water Characteristic Curve Model for Compacted Bentonite Considering Temperature Variation (온도 변화를 고려한 압축 벤토나이트 완충재의 함수특성곡선 모델 평가)

  • Yoon, Seok;Jeon, Jun-Seo;Go, Gyu-Hyun;Kim, Geon-Young
    • Journal of the Korean Geotechnical Society
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    • v.36 no.10
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    • pp.33-39
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    • 2020
  • A geological repository has been considered as an option for the disposal of high-level radioactive waste (HLW). The HLW is disposed in a host rock at a depth of 500~1,000 meters below the ground surface based on the concept of engineered barrier system (EBS). The EBS is composed of a disposal canister, buffer material, backfill material, and gap-filling material. The compacted bentonite buffer is very important since it can restrain the release of radionuclide and protect the canister from the inflow of ground water. The saturation of the buffer decreases because high temperature in a disposal canister is released into the surrounding buffer material, but saturation of the buffer increases because of the inflow of ground water. The unsaturated properties of the buffer are critical input parameters for the entire safety assessment of the engineered barrier system. In Korea, Gyeongju bentonite can be considered as a candidate buffer material, but there are few test results of the unsaturated properties considering temperature variation. Therefore, this paper conducted experiment of soil-water characteristic curve for the Gyeongju compacted bentonite considering temperature variation under a constant water content condition. The relative error showed approximately 2% between test results and modified van-Genuchten model values.