• Title/Summary/Keyword: Water Object

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Restoration of underwater images using depth and transmission map estimation, with attenuation priors

  • Jarina, Raihan A.;Abas, P.G. Emeroylariffion;De Silva, Liyanage C.
    • Ocean Systems Engineering
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    • v.11 no.4
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    • pp.331-351
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    • 2021
  • Underwater images are very much different from images taken on land, due to the presence of a higher disturbance ratio caused by the presence of water medium between the camera and the target object. These distortions and noises result in unclear details and reduced quality of the output image. An underwater image restoration method is proposed in this paper, which uses blurriness information, background light neutralization information, and red-light intensity to estimate depth. The transmission map is then estimated using the derived depth map, by considering separate attenuation coefficients for direct and backscattered signals. The estimated transmission map and estimated background light are then used to recover the scene radiance. Qualitative and quantitative analysis have been used to compare the performance of the proposed method against other state-of-the-art restoration methods. It has been shown that the proposed method can yield good quality restored underwater images. The proposed method has also been evaluated using different qualitative metrics, and results have shown that method is highly capable of restoring underwater images with different conditions. The results are significant and show the applicability of the proposed method for underwater image restoration work.

Analysis of Land Cover Classification and Pattern Using Remote Sensing and Spatial Statistical Method - Focusing on the DMZ Region in Gangwon-Do - (원격탐사와 공간통계 기법을 이용한 토지피복 분류 및 패턴 분석 - 강원도 DMZ일원을 대상으로 -)

  • NA, Hyun-Sup;PARK, Jeong-Mook;LEE, Jung-Soo
    • Journal of the Korean Association of Geographic Information Studies
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    • v.18 no.4
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    • pp.100-118
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    • 2015
  • This study established a land-cover classification method on objects using satellite images, and figured out distributional patterns of land cover according to categories through spatial statistics techniques. Object-based classification generated each land cover classification map by spectral information, texture information, and the combination of the two. Through assessment of accuracy, we selected optimum land cover classification map. Also, to figure out spatial distribution pattern of land cover according to categories, we analyzed hot spots and quantified them. Optimal weight for an object-based classification has been selected as the Scale 52, Shape 0.4, Color 0.6, Compactness 0.5, Smoothness 0.5. In case of using the combination of spectral information and texture information, the land cover classification map showed the best overall classification accuracy. Particularly in case of dry fields, protected cultivation, and bare lands, the accuracy has increased about 12 percent more than when we used only spectral information. Forest, paddy fields, transportation facilities, grasslands, dry fields, bare lands, buildings, water and protected cultivation in order of the higher area ratio of DMZ according to categories. Particularly, dry field sand transportation facilities in Yanggu occurred mainly in north areas of the civilian control line. dry fields in Cheorwon, forest and transportation facilities in Inje fulfilled actively in south areas of the civilian control line. In case of distributional patterns according to categories, hot spot of paddy fields, dry fields and protected cultivation, which is related to agriculture, was distributed intensively in plains of Yanggu and in basin areas of Cheorwon. Hot spot areas of bare lands, waters, buildings and roads have similar distribution patterns with hot spot areas related to agriculture, while hot spot areas of bare lands, water, buildings and roads have different distributional patterns with hot spot areas of forest and grasslands.

Multi-resolution SAR Image-based Agricultural Reservoir Monitoring (농업용 저수지 모니터링을 위한 다해상도 SAR 영상의 활용)

  • Lee, Seulchan;Jeong, Jaehwan;Oh, Seungcheol;Jeong, Hagyu;Choi, Minha
    • Korean Journal of Remote Sensing
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    • v.38 no.5_1
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    • pp.497-510
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    • 2022
  • Agricultural reservoirs are essential structures for water supplies during dry period in the Korean peninsula, where water resources are temporally unequally distributed. For efficient water management, systematic and effective monitoring of medium-small reservoirs is required. Synthetic Aperture Radar (SAR) provides a way for continuous monitoring of those, with its capability of all-weather observation. This study aims to evaluate the applicability of SAR in monitoring medium-small reservoirs using Sentinel-1 (10 m resolution) and Capella X-SAR (1 m resolution), at Chari (CR), Galjeon (GJ), Dwitgol (DG) reservoirs located in Ulsan, Korea. Water detected results applying Z fuzzy function-based threshold (Z-thresh) and Chan-vese (CV), an object detection-based segmentation algorithm, are quantitatively evaluated using UAV-detected water boundary (UWB). Accuracy metrics from Z-thresh were 0.87, 0.89, 0.77 (at CR, GJ, DG, respectively) using Sentinel-1 and 0.78, 0.72, 0.81 using Capella, and improvements were observed when CV was applied (Sentinel-1: 0.94, 0.89, 0.84, Capella: 0.92, 0.89, 0.93). Boundaries of the waterbody detected from Capella agreed relatively well with UWB; however, false- and un-detections occurred from speckle noises, due to its high resolution. When masked with optical sensor-based supplementary images, improvements up to 13% were observed. More effective water resource management is expected to be possible with continuous monitoring of available water quantity, when more accurate and precise SAR-based water detection technique is developed.

A Study on Seok-kok Lee, Kyu-jun's Pu-yang-non (석곡 이규준의 부양론(扶陽論)에 관한 연구(硏究))

  • Hwang, In-Deok
    • Journal of Korean Medical classics
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    • v.12 no.2
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    • pp.16-53
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    • 1999
  • On the viewpoint of Nae-Kyung and Ju-Yeok, the Seok-Kok's Pu-Yang-Non and other oriental medical doctor's Po-Eum-Eok-Yang, Pu-Yang-Eok-Eum theory which are on the basis of the Kun-Shin-Sang-Wha theory of Nae-Kyung and Myung-Mun theory of Nan-Kyung were compared and studied. The results were as follows : 1. Ju-Yeok and Nae-Kyung said the South is Fire. And explained it as the chief object of life activity by likening to king or saint. And said the North is Water. but didn't mentioned that there exists Fire. The activity of Kun-Wha is regarded as the the chief object of life activity and the Shin-Su can be vatalized by receiving the Shim-Kun-Wha. Therefore, the Seok-Kok's opinion that Shang-Wha is the Fire received by Shin-Su matchs the theory of Nae-Kyung and Nan-Kyung. 2. The Kidney(Shin) in Nae-Kyung means Puk-Bang- Han-Su(The North Cold Water) which has two characters, charging and discharging, ascending and descending. The paragrap "Kam-Ga-Seub(坎加習)" in Ju-Yeok means Puk-Bang-Su(The North Water) which also has two characters, charging and discharging, ascending and descending. The beginning and the end. And One Eum and Two Yang of Ri Sign of divination(離卦) cannot be divided into Su-Jang and Wha-Jang, the same as that, One Yang and Two Eum of Kam Sign of divination(坎卦) is Puk-Bang-Han-Su which cannot be divided into Shin and Myung-Mun. The theory of Choa-Shin-Woo-Myung-Mun of Nan-Kyung is the result that the Shin which has two characters is regarded as two organs. Therefore, from the viewpoint of Nae-Kyung and Ju-Yeok, the Seok-Kok's opinion that the Shin is the Puk-Bang-Han-Su which charges from the right and discharges to the left is more proper. 3. For the first time, the right kidney(Woo-Shin) defined as Myung-Mun in the Nan-Kyung and it is trailblazing theory which dosen't exist in the Nae-Kyung. But from the viewpoint of Nae-Kyung, Myung-Mun-Shang-Wha which some oriental medical doctors thought importantly is considered as Shim-Po which is in charge of the order of Shim(心命). 4. The rush of heat to the upper part(上熱) is raised by blind acting of Shang-Wha which exists in the lower part. This theory is on the basis of the Myung-Mun-Shang-Wha theory of Nan-Kyung. The theory that Wha is in the Shin(Kidney) doesn't exist and only the theory exists that the fever happens by the Kun-Wha not going down but ascending in the Nae-Kyung. Therefore the Shang-Wha blind acting theory of the lower part is not coincided with the theory of Nae-Kyung. 5. When the Vital power(陽氣) is blocked by bad tendencies(邪氣) like uncontrolled joy and anger or too much cold and heat etc, the trapped heat(鬱熱) or Ascending Shang-Wha apper, so Vital power itself cannot have blind activity or excess. Therefore, the theory of oriental medical doctors that the remaining vital power is the fire(氣有餘便是火) cannot be materialized. 6. On the basis of the Woo-Shin-Myung-Mun theroy, oriental medical doctors attached importance to Shin-Eum and Shin-Yang. So they emphasized on Ja-Eum-Gang-Wha or On-Bo-Shin-Yang for curing the Fire. Contrarily, On the viewpoint of siding with the vital power which is the Good and repressing the bad tendency which is the Bad, and another viewpoint that when the vital power which is Shim-Kun-Wha moves through the body consistently and fills up the body, then the enery and blood can be made, the Seok-Kok's theory is coincided with the theory of Nae-Kyung.

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Simulation of Solitary Wave-Induced Dynamic Responses of Soil Foundation Around Vertical Revetment (고립파 작용하 직립호안 주변에서 지반의 동적응답에 관한 수치시뮬레이션)

  • Lee, Kwang-Ho;Yuk, Seung-Min;Kim, Do-Sam;Kim, Tae-Hyeong;Lee, Yoon-Doo
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.26 no.6
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    • pp.367-380
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    • 2014
  • Tsunami take away life, wash houses away and bring devastation to social infrastructures such as breakwaters, bridges and ports. The targeted coastal structure object in this study can be damaged mainly by the tsunami force together with foundation ground failure due to scouring and liquefaction. The increase of excess pore water pressure composed of oscillatory and residual components may reduce effective stress and, consequently, the seabed may liquefy. If liquefaction occurs in the seabed, the structure may sink, overturn, and eventually increase the failure potential. In this study, the solitary wave was generated using 2D-NIT(Two-Dimensional Numerical Irregular wave Tank) model, and the dynamic wave pressure acting on the seabed and the estimated surface boundary of the vertical revetment. Simulation results were used as an input data in a finite element computer program(FLIP) for elasto-plastic seabed response. The time and spatial variations in excess pore water pressure, effective stress, seabed deformation, structure displacement and liquefaction potential in the seabed were estimated. From the results of the analysis, the stability of the vertical revetment was evaluated.

Physical Properties of Recycled Sidewalk Pavement Using Wood Chip (Wood Chip을 사용한 자원순환형 보도 포장체의 물성에 관한 연구)

  • Yu, Hyeok-Jin;Choi, Jae-Jin
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.5 no.2
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    • pp.91-96
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    • 2010
  • The purpose of this study is to find problems about pedestrian road of tourist resort and to make new type of sidewalk pavement with wood chip and binder using urethane resin on the parks and tourist resort. The wood chip pavement has new economics and durability with comfortable texture. Samples of these pavement materials were tested for tensile strength, permeability and ball rebound value. Also, after immersion for 24 hours, tensile strength, samples' thickness and weight were measured and discussed the strength reduction according to the water immersion. Tensile strength experimentation was examined on dry condition and water immersion. The result of examination on dry condition was 1.06MPa and on water immersion was 0.67MPa. The results showed 36.8% decreasing rate of tensile strength. Permeability experiment test based on field permeability method of pavement were conducted as a result, permeability coefficients were in the range of 0.67~0.78mm/s that all exceeds object permeability coefficient. Elasticity experiment was based on elasticity test method of Japan road association. GB coefficient was 21% and SB coefficient was 10%. GB coefficient and SB coefficient increased if fine aggregate were increased.

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Environmental Factors Related to Mass Moralities of Young Red Seabream (Pagrus major) in the Artificial Seed Production (일본산 참돔, Pagrus major 종묘생산과정중 사육수 변화로 인한 대량폐사)

  • 최상덕;정관식;김호진;김성수
    • Journal of Aquaculture
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    • v.11 no.2
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    • pp.203-212
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    • 1998
  • As seed production program is growing prosperously in various fishes in southern Korea, disease problems in larval and juvenile stages have emerged as a new research object. The following results were obtained from investigation about environmental factors related to mass mortalities of young Kinki red seabream, Pagrus major in process of artificial seedling production. Total length of red seabream larvae hatched was 2.93mm, and became 18.83~20.12mm at day 40. The first noticeable mortality of red seabream larvae (7.98~9.37mm) occurred in 25~30 day-old fish with the survival rates of 59.8~60.3%. Thereafter the mortality of larvae decreased, survival rate was 20.5~25.45% in day 40. After 20~30 days, the quality of pond water was bellow II class. During the experimental period COD, $PO_4$-P, $NO_2$-N, $NO_3$-N and $NH_$-N increased up to 3, 7, 34, 6 and 8 times, respectively, compared to initial ones. The number of viable bacteria in pond water and seabream larvae were $6.3{\times}10^6$~$2.3{\times}10^7$ cfu/ml, 4.3~$7.4{\times}10^6$ cfu/g in day 25, respectively. Among the isolated bacteria from the diseased red seabream in day 25, Vibrio spp. was considered to be the causative organism. External symptoms of this disease were floated, spined near the surface and inflated abdomen. When the isolated strain of the Vibrio was bathed to seabream larvae, $LD_50$ of seabream larvae was over $10^6$ cfu/ml of Vibrio spp.

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Application of Chiu's Two Dimensional Velocity Distribution Equations to Natural Rivers (Chiu가 제안한 2차원 유속분포식의 자연하천 적용성 분석)

  • Lee, Chan-Joo;Seo, Il-Won;Kim, Chang-Wan;Kim, Won
    • Journal of Korea Water Resources Association
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    • v.40 no.12
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    • pp.957-968
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    • 2007
  • It is essential to obtain accurate and highly reliable streamflow data for quantitative management for water resources. Thereafter such real-time streamflow gauging methods as ultrasonic flowmeter and index-velocity are introduced recently. Since these methods calculate flowrate through entire cross-section by measuring partial velocities of it, rational and theoretical basis are necessary for accurate estimation of discharge. The purpose of the present study lies in analysis on the applicability of Chiu#s(1987, 1988) two dimensional velocity distribution equations by applying them to natural rivers and by comparing simulated velocity distributions with observed ones obtained with ADCP. Maximum and mean velocities are calculated from observed data to estimate entropy parameter M. Such isovel shape parameters as h and $\beta_i$ are estimated by object function based on least squares criterion. In case optimized parameters are applied, Chiu#s velocity distributions fairly well simulate observed ones. By using 14 simulated data sets which have relatively high correlation coefficients, properties of parameters are analyzed and h, $\beta_i$ are estimated for velocity-unknown river sections. When estimated parameters are adopted for verification, simulated velocity distributions well reproduce real ones. Finally, calculated discharges display rough agreement with measured data. The results of the present study mean that if parameters related are properly estimated, Chiu#s velocity distribution is likely to reproduce the real one of natural rivers.

Modulation of antioxidant defense system in the brackish water flea Diaphanosoma celebensis exposed to bisphenol A (비스페놀 A에 대한 기수산 물벼룩의 항산화 시스템의 변화)

  • Yoo, Jewon;Cha, Jooseon;Kim, Hyeri;Pyo, Jinwoo;Lee, Young-Mi
    • Korean Journal of Environmental Biology
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    • v.37 no.1
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    • pp.72-81
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    • 2019
  • Bisphenol A (BPA), a representative endocrine disrupting chemicals, has adverse effects on growth, development and reproduction in aquatic organisms. The object of this study was to investigate the modulation of antioxidant enzyme-coding genes using quantitative real time RT-PCR (qRT-PCR), enzyme activity and total protein content, to understand oxidative stress responses after exposure to BPA for 48 h in brackish water flea Diaphanosoma celebensis. The BPA ($3mg\;L^{-1}$) significantly upregulated the expression of Cu/Zn-SOD, Mn-SOD, and catalase (CAT) mRNA. Three GST isoforms (GST-kappa, GST-mu, and GST-theta) mRNA levels significantly increased at the rate of $0.12mg\;L^{-1}$ of BPA. In particular, GST-mu showed the highest expression level, indicating its key role in antioxidant response to BPA. SOD activity was induced with a concentration-dependent manner, and total protein contents was reduced. These findings indicate that BPA can induce oxidative stress in this species, and these antioxidants may be involved in cellular protection against BPA exposure. This study will provide a better understanding of molecular mode of action of BPA toxicity in aquatic organisms.

Magritte's drawings and Lacan's Subject theory: Gaze, Encounter with the world (마그리트 회화와 라캉의 주체론 - 응시, 세계와의 조우)

  • Baek, Jin-Hwa
    • The Journal of Art Theory & Practice
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    • no.5
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    • pp.7-24
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    • 2007
  • The subject is connected with a structure named "The Symbolic" to Lacan, but he denied that the subject is explained simply as a fruit of language and "Other". From his point of view, passing through Subject, De-formation and Crack over it is designated as foundation of generation and creation rather than our destined defect. It should not be understood that subject of "The Real" is a concept of the subject free itself from restraint of "The Symbolic". However, this does not mean he asserts "Subject" is something incapable of being controlled by the unknown power. The problem is that this autonomous existence meets inside of it with something "more than one's own self" by "circulating around itself" like a permanent star. This is the indication of a "stranger in the middle of my privacy", or "extimit$\'{e}$", a coined-word by Lacan. Perhaps "Subject" is nothing more than the name of distance of object which is "too hot" to come close, and of this circulating movement. It's because of this object that the real subject stands against generalization and the subject can't be restored to any place in symbolic order-even though it is empty. The part which is told from Lacan's structural theory, that is to say, an importance to Lacan is that his Subject theory is not suggested or denied as a manual structure. On the contrary, it is a study of the relationship between the settled symbol that included in "real subject which is a unconscious one" and the symbolic subject hold- that is a metaphysical subject in general meaning. In Lacan's enlarged concept of subject beyond symbolic reality, it is noticeable that it gives justifiability to the union of a medium of different nature in artistic expression. We can recognize that the unconscious world is a living space which enables it to be a "condition of human being", not something dark under the surface of water through Magritte's(Rene Magritte, 1898~1967) surrealistic works. In other words, Magritte's art secures a core dimension of human nature through a mysterious gap of conscious and settled space. Magritte's drawings often evokes strange and unsettling feelings in people who view his paintings. This is because routine objects are found in "unsuitable" places from which we usually find them in our everyday lives. "Reality" in Magritte's paintings makes it aware that it is a strained field of concealment and disclosure basically between truths, and we can learn that his behavior to overturn to paint in-visible things is finally an effort to restore the "real subject" to the viewer's reality. In other words, such reversion arouses a nostalgic desire for the objects existing in their original appearance as they are - natural condition that our gaze had not been distorted yet by anamorphic stains. - and the state when we are conscious of them normally. Such desire offers an opportunity for us to get out of mental depression rather than operates to us as an abnormal crack. It's a successive process of effort to search for lost subject and Paradise Lost facing up to reality of subject human that is to be a subject of world and life are ousted from their place by structure and authority of culture.

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