• Title/Summary/Keyword: 조석효과

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A Wavelet CODEC that is with JPEG (JPEG와 호환 가능한 Wavelet CODEC)

  • Kim, Yong-Gyu;Kim, Dok-Gyu;Jo, Seok-Pal
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.38 no.1
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    • pp.43-53
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    • 2001
  • WT(Wavelet Transform) is used to avoid blocking effect that is the disadvantage of JPEG using DCT(Discrete Cosine Transform). Because the proposed coding scheme is the same as JPEG, the proposed algorithm is compatible with that of JPEG. To achieve the goal, WT'ed image is reconstructed into 8$\times$8 coding block. Each coding block is quantized with the proposed weighting matrix that is derived from human visual characteristic and error analysis in WT'ed domain. By experiments, the proposed algorithm is superior to JPEG, in terms of PSNR(Peak Signal to Noise Ratio) and WMSE(Weighted Mean Square Error).

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High-Current Time-Lapse Electrical Imaging in Marine Sediments Area (해성퇴적층 하부지반 대전류 time-lapse 전기탐사)

  • Jung, Hyun-Key;Geo, Dong-Kweon Lee
    • 한국지구물리탐사학회:학술대회논문집
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    • 2006.06a
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    • pp.109-112
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    • 2006
  • Successful field test results for high-current time-lapse electrical imaging in marine sediments area are discussed. Because field trial by commercially available equipments were failed, self-developed system which supports transmitting current up to 5 ampere was used. Some weak zones due to local fractures were detected, but the weak zone effect in this area by time-lapse measurements from sea level change was minor.

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The Study of Dynamic Tidal Power for Practical Use (동적 조력 발전의 실용화를 위한 연구)

  • Park, Young Hyun
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.31 no.6
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    • pp.379-385
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    • 2019
  • Dynamic Tidal Power, which is a kind of tidal power generation, requires huge structures, because it is conducted by using the phase difference caused by the diffraction effect of tides. Economic feasibility is most demanded for practical use, and various studies have been conducted for this purpose. In this study, unlike existing methods, several structures were installed to improve it by increasing power generation. The flow changes around the structures were studied, and it was found that proper spacing between structures was necessary for efficient power generation.

Examination of Seismic Performance for Structure with Seismic Members made by High Strength Steel (고강도강 내진성능 향상부재를 적용한 건물 성능 비교)

  • Kim, Moonjeong;Ha, Tae Uk;Cho, Sukhee
    • Journal of Korean Society of Steel Construction
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    • v.27 no.3
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    • pp.281-288
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    • 2015
  • Seismic members like damper do not have any treatment of preventing story stiffness reduction after elastic yielding of stories causing story collapse. This paper suggests a method able to prevent story stiffness reduction using high-strength steel. This paper suggests these also : (1) High-strength steel stud column reinforcing story stiffness reduction until story drift 0.02rad can be designed in small area without adjusting layout. (2) Suggested seismic member installing at lowest level shows effects to preventing deformation concentration under huge seismic waves.

Effect of Diuresis on Plasma Renin Activity and Aldosterone Concentration in Normal and Toxemic Pregnancy (정상임부와 임신중독환자의 혈장 Renin활성도 및 Aldosterone 농도에 미치는 이뇨의 효과)

  • Sung, H.K.;Lee, H.S.;Cho, S.S.;Koh, J.H.;Lee, J.K.;Kim, H.S.
    • The Korean Journal of Nuclear Medicine
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    • v.7 no.1
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    • pp.45-50
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    • 1973
  • The changes of plasma renin activity, aldosterone concentration, serum sodium-, and potassium levels were studied before and after the water loading followed by diuretics injection. The materials were: 13 non-, 11 normal-, and 11 toxemic pregnancy cases. The plasma renin activity and aldosterone concentration of the cord and postpartum blood were also measured. Following were the results: 1. The plasma renin activity was elevated significantly in normal pregnancy, and slightly in toxemic pregnancy. The serum sodium levels were decreased in pregnancy. 2. The plasma aldosterone concentration was slightly decreased in normal pregnancy, and slightly increased in toxemic pregnancy, however, statistically insignificant. 3. The plasma renin activity of the cord and postpartum blood were lower than those of pregnancy cases. 4. The changes of plasma renin activity after the diuretic administration showed an initial increase, which recovered within 2 hours. These changes were the least in normal pregnancy, and the most in toxemic pregnancy. 5. The changes of plasma aldosterone concentration after the diuretic administration were similar to those of plasma renin activity, although the variations were not so wide.

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창의성 신장을 위한 영재 심화학습 프로그램의 효과에 대한 교사와 영재아의 평가 비교 연구

  • Jang, Young-Sook;Cho, Seok-Hee
    • Journal of Gifted/Talented Education
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    • v.10 no.1
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    • pp.33-53
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    • 2000
  • The purpose of this study was to compare the evaluation of students and teachers on the degree of students' improvement in terms of creativity after participating in enrichment programs for the gifted. Two topics in each of the Language Art and Mathematics were implemented to gifted students in grade 2 and 3 in one of the elementary schools in Kyung-Ki province and one private gifted education center for 12 times during the summer. The results showed that the young gifted students could monitor their performances very well and the evaluation of their creativity were consistently more positive than that of their teachers who taught them. They were significantly more positive regarding their creativity in mathematics than in Language Art. The results imply that young gifted children can evaluate their creativity reliably and consistently. Therefore, the teachers should try to understand and consider their own evaluation about their creativity in planning educational programs for the gifted. In the following studies, it is necessary to have pro- and post-test data on creativity collected by diverse methods and to include older students as subjects to see whether the results of this study are generalizable to older students.

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Study on Reduction of Flooding Area Using XP-SWMM at Inundation Region in the Reclaimed Land near the Incheon Bridge (XP-SWMM 모형을 활용한 인천교 매립지 침수 피해 경감에 대한 연구)

  • Choi, Gye Woon;Lee, Ho Sun;Han, Man Shin;Lee, Byung Joo
    • Proceedings of the Korea Water Resources Association Conference
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    • 2004.05b
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    • pp.500-505
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    • 2004
  • 인천지역은 지형이 낮은 관계로 배수가 원활하지 못한 지역이 있고 또한 서해안 특유의 높은 조석간만의 차이로 인하여 만조시에는 배수가 어려워 침수가 발생하는 지역이 많다. 이에 대하여 매립된 인천교 주변 하수관거의 통수능을 수치해석을 통하여 분석하고 배수 체계 및 인천교 주변의 내수 배제에 대한 문제점을 파악하여 침수 개선방안을 제시하므로써 인천교 주변 매립지의 침수피해를 경감시키고자 하였다. 통수능 분석을 위한 수치해석 프로그램으로 SWMM모형이 선정되었으며 보다 정확한 해석을 위하여 대상 유역을 수십 개의 소유역으로 구분하여 소유역의 유출을 계산한 후에 관로 내 흐름에 대하여 해석을 실시하였다. 소유역에서의 보다 정확한 유출량 산정을 위하여 평균유출계수(C값)를 사용치 않고 소유역마다 산출된 별도의 유출계수를 이용하였다. 유출량 산정을 위한 강우강도는 기존의 인천대공식과 최근의 강우량을 감안한 해석결과를 비교하여 기존의 인천대 공식 사용이 가능함을 판단하고 이를 사용하여 20년, 30년 빈도의 확률강우강도를 산정하였다. 설계빈도에 대하여 유역 내 침수 피해를 경감시키는 4개의 대안을 선정하여 각각의 대안에 대한 해석을 실시하여 침수피해 개선효과를 비교하여 최적의 대안을 판단하였다.

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Numerical Modeling of Cohesive Sediment Transport at Mokpo Coastal Zone (목포해역 점착성 퇴적물의 수송에 관한 수치모의)

  • Jung T.S.;Kim T.S.;Jeong D.K.
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.9 no.1
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    • pp.36-44
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    • 2006
  • Cohesive sediment transport in coastal region has been studied by numerical modeling. A finite element numerical model was setup to simulate hydrodynamics and sediment transport in the coastal region with complex topography. Only physical features of observed sediments has been used to determine erosion rates of bottom sediments together with the previous research results. The simulation results using the simply determined equation of erosion rates were compared with time variations of the observed SS concentration and showed good agreements. In conclusion, this method can be used to estimate transport of cohesive sediment conveniently.

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Color Collection of LCD Monitor Using High-order Multilayer Neural Network (고차 다층구조 신경회로망을 이용한 LCD 모니터의 색 보정)

  • Jung, Jae-Hoon;Lee, Dong-Wook;Ahn, Kang-Sic;Cho, Seok-Je
    • The KIPS Transactions:PartB
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    • v.11B no.2
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    • pp.169-176
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    • 2004
  • This paper presents a new color correction method for color reproduction on LCD-based monitor by means of high-order multilayer neural networks. LCD monitors have nonlinear characteristics from various displaying system components. To overcome these nonlinearities and produce quality image, we need a nonlinear transformer for color coordinate transformation between the LCD monitor coordinates and the input color stimulus values. A high-order multilayer neural network is effectively trained to learn a mapping to determine the required color value of monitors for producing a given color stimulus. From the experimental results, the proposed method is effective in reproducing the color images.

The Impact of Leader-Member Exchange of Employees in Shipping and Port Companies on Customer Orientation: The Dual Mediating Effect of Psychological Empowerment and Job Engagement (해운·항만 종사자의 리더-구성원 교환관계가 고객지향성에 미치는 영향: 심리적 임파워먼트와 직무열의의 이중 매개효과)

  • Cho, Sok-Jung;Jeon, Jeong-Ho;Li, Yi-Ran;Lee, Jong-Min
    • Korea Trade Review
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    • v.44 no.5
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    • pp.65-92
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    • 2019
  • The purposes of this study are to examine the impact of LMX on psychological empowerment, job engagement, and customer orientation, and to analyze the dual mediation effect of psychological empowerment and job engagement. To conduct this study, we used 333 questionnaires collected by members of domestic companies and organizations. Analyses results are as follows: First, LMX has no positive effect on customer orientation. Second, in the relationship between LMX and customer orientation, psychological empowerment and job engagement play a mediating role. Third, in the relationship between LMX and customer orientation, psychological empowerment and Job Engagement play a dual mediating role. The results of this study suggest the following implications. The theoretical implication is that this study once again confirmed behavior patterns such as cognition, emotion, attitude, and behavior of members in the organization. In addition, this study contributes to the literature by explaining that these behavior patterns by way of social exchange theory. The practical implication is that this study confirmed that members in the management field need to utilize a customer orientation in order to achieve the organization's goal efficiently and effectively.