• Title/Summary/Keyword: SPATIAL SCALE

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Mixing Zone Analysis on Outfall Plume considering Influence of Temperature Variation (수온 변화의 영향을 고려한 방류관 플룸의 혼합역 분석)

  • Kim Ji-Yeon;Lee Joong-Woo
    • Journal of Navigation and Port Research
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    • v.28 no.10 s.96
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    • pp.947-953
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    • 2004
  • As a large scale port development in coastal waters proceeds step by step and populations in the vicinity of port are getting increased, the issue on 'how to dispose the treated municipal water and wastewater in harbor' brings peoples' concern. The submarine outfall system discharges the primary or secondary treated effluent at the coastline or in deep water, or between these two. The effluent, which has a density similar to that of fresh water, rises to the sea surface forming plume or jet, together with entraining the surrounding sea water and becomes very dilute. We intended in this paper to investigate the impact on dilution of effluent and the behavior of flume under the conditions of the seasonal and spatial temperature variations, which have not been noticeable in designing effective marine outfall system. To predict and analyze the behaviour and dilution characteristics of plume not just with the effluent temperature, but also with the seasonal variation of temperature of surround water, CORMIX( Cornell Mixing Zone Expert System)-GI have been applied. The results should be used with caution in evaluation the mixing zone characteristics of discharged water. We hope to help for the effective operation of outfall system, probable outfall design, protection of water quality, and warm water discharges from a power plant, etc.

Numerical Study on Operating Factors Affecting Performance of Surfactant-Enhanced Aquifer Remediation Process (계면활성제 증진 대수층 복원 프로세스에 영향을 미치는 운영 인자들에 대한 수치 연구)

  • Lee, Kun-Sang
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.7
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    • pp.690-698
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    • 2010
  • Contamination of groundwater resources by organic chemicals has become an issue of increasing environmental concern. Surfactant-enhanced aquifer remediation (SEAR) is widely recognized as one of the most promising techniques to remediate organic contaminations in-situ. Solutions of surfactant or surfactant with polymer are used to dramatically expedite the process, which in turn, may reduce the treatment time of a site compared to use of water alone. In the design of surfactant-based technologies for remediation of organic contaminated aquifers, it is very important to have a considerable analysis using extensive numerical simulations prior to full-scale implementation. This study investigated the formation and flow of microemulsions during SEAR of organic-contaminated aquifer using the finite difference model UTCHEM, a three-dimensional, multicomponent, multiphase, compositional model. The remediation process variables considered in this study were the sequence of injection fluids, the injection and extraction rate, the concentrations of polymer in surfactant slug and chase water, and the duration of surfactant injection. For each variable, temporal changes in injection and production wells and spatial distributions of relative saturations in the organic phase were compared. Cleanup time and cumulative organic recovery were also quantified. The study would provide useful information to design strategies for the remediation of nonaqueous phase liquid-contaminated aquifers.

Review on Wandering Behavior in Persons with Dementia (치매 노인의 배회행동에 관한 문헌 조사)

  • HongSon, Gwi-Ryung
    • Perspectives in Nursing Science
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    • v.3 no.1
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    • pp.35-45
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    • 2006
  • In Korea, about 8.3% over aged 65 are suffering from Alzheimer's disease or other type of dementia. Among dementia-related behaviors, wandering is the one of strongest factors on burden and stress of caregivers. On Lee and Kwon's report with community living persons with dementia, upto 85% of caregivers reported wandering as a problem. Wandering is a frequently encountered problem in communities and long-term care facilities, but it is among least understood dementia. related behavior. Despite the prevalence of wandering, its significant adverse outcomes, and the increase in persons with dementia in Korea, no systematic research has been conducted in Korea. The purpose of this study is to review on literature related to wandering behavior among persons with dementia. The specific topics related to wandering are included: definition, the prevalence of dementia and wandering behavior, the influencing factor on wandering, outcomes of wandering behavior, and the measurement method. Wandering is defined as "aimless walking" and "Meandering, aimless or repetitive locomotion that exposes one to harm and is incongruent with boundaries, limits, or obstacles". Wandering is viewed as a problematic behavior, however, it has to be understood as need-driven compromised behavior. For example, wandering may be an expression of searching for familiar person and/or place. Recently, in Korea, there is an effort for establishing the therapeutic environment for elders who are wanderers in long-term-care facilities. Cognitive impairment of persons with dementia is found to be a consistent factor on wandering behavior through many national and international studies. The adverse outcomes of wandering are serious problem in persons with dementia as well as their caregivers. The adverse outcomes include falls, fractures, getting lost, use of restraints, or even death. In fact, wandering is one of the major reasons for a patient to be institutionalized. For measurement of wandering behavior, two methods are broadly used: observation using stop watch, and survey form. A revised instrument of the Korean version of Algase wandering scale (K_RAWS) is established the psychometric properties (Son, Song, & Lim, 2006) demonstrating valid and reliable instrument in measuring wandering behavior among persons with dementia who are residing in communities. K_RAWS has a 39 items with six subscales including persistent walking, repetitive walking, spatial disorientation, eloping behavior, negative outcome, and mealtime impulsivity. In conclusion, studies including the prevalence of wandering behavior and predictive factors on wandering should be conducted to understand wandering clearly before developing any types of intervention.

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Agricultural drought monitoring using the satellite-based vegetation index (위성기반의 식생지수를 활용한 농업적 가뭄감시)

  • Baek, Seul-Gi;Jang, Ho-Won;Kim, Jong-Suk;Lee, Joo-Heon
    • Journal of Korea Water Resources Association
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    • v.49 no.4
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    • pp.305-314
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    • 2016
  • In this study, a quantitative assessment was carried out in order to identify the agricultural drought in time and space using the Terra MODIS remote sensing data for the agricultural drought. The Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) were selected by MOD13A3 image which shows the changes in vegetation conditions. The land cover classification was made to show only vegetation excluding water and urbanized areas in order to collect the land information efficiently by Type1 of MCD12Q1 images. NDVI and EVI index calculated using land cover classification indicates the strong seasonal tendency. Therefore, standardized Vegetation Stress Index Anomaly (VSIA) of EVI were used to estimated the medium-scale regions in Korea during the extreme drought year 2001. In addition, the agricultural drought damages were investigated in the country's past, and it was calculated based on the Standardized Precipitation Index (SPI) using the data of the ground stations. The VSIA were compared with SPI based on historical drought in Korea and application for drought assessment was made by temporal and spatial correlation analysis to diagnose the properties of agricultural droughts in Korea.

Accuracy Assessment on the Stereoscope based Digital Mapping Using Unmanned Aircraft Vehicle Image (무인항공기 영상을 이용한 입체시기반 수치도화 정확도 평가)

  • Yun, Kong-Hyun;Kim, Deok-In;Song, Yeong Sun
    • Journal of Cadastre & Land InformatiX
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    • v.48 no.1
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    • pp.111-121
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    • 2018
  • RIn this research, digital elevation models, true-ortho image and 3-dimensional digital complied data was generated and evaluated using unmanned aircraft vehicle stereoscopic images by applying photogrammetric principles. In order to implement stereoscopic vision, digital Photogrammetric Workstation should be used necessarily. For conducting this, in this study GEOMAPPER 1.0 is used. That was developed by the Ministry of Trade, Industry and Energy. To realize stereoscopic vision using two overlapping images of the unmanned aerial vehicle, the interior and exterior orientation parameters should be calculated. Especially lens distortion of non-metric camera must be accurately compensated for stereoscope. In this work. photogrammetric orientation process was conducted using commercial Software, PhotoScan 1.4. Fixed wing KRobotics KD-2 was used for the acquisition of UAV images. True-ortho photo was generated and digital topographic map was partially produced. Finally, we presented error analysis on the generated digital complied map. As the results, it is confirmed that the production of digital terrain map with a scale 1:2,500~1:3,000 is available using stereoscope method.

Exploring housing consumption adjustment of pre-retirees after retirement using ordered probit model in terms of different housing size (순위프로빗모형을 이용한 예비은퇴자의 주택소비 조정 의향 결정요인 분석 - 주택규모의 변화를 중심으로 -)

  • Lee, So-Young;Kim, Ji-Hyun;Choi, Youn-Young
    • Journal of Cadastre & Land InformatiX
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    • v.48 no.1
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    • pp.35-53
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    • 2018
  • Recently, there is a growing interest in housing policy to prepare for the aging society. The purpose of this study is exploring the factors that explain housing consumption and adjustment of pre-retirees after retirement. 1,351 samples were collected from A bank and analyzed. There categories of housing consumption adjustment were considered including downsizing, maintain, and upsizing. Gender, educational level, housing size, housing type, asset size, and willingness to work after retirement were examined to see if they can explain the housing consumption adjustment of pre-retirees using orderd- probit model. The finding of this study is that housing size, asset size, and willingness to work after retirement statistically significantly explain the housing consumption adjustment. At specific, firstly, if the current size of the housing is relatively large, it is highly likely to downsize housing after retirement. Second, pre-retiree whose assets exceeded 1 billion won were more likely to scale up housing than assets of over 300 million to less than 500 million won. Lastly, unless there is absolutely no willingness to work after retirement, it is indicated that it intends to up-sizing consumption rather than down-sizing adjustment. The results of this study can provide useful information for the housing policy in order to prepare for the (post) aged society.

Development of Line Density Index for the Quantification of Oceanic Thermal Fronts (해양의 수온전선 정량화를 위한 선밀도 지수 개발)

  • Cho, Hyun-Woo;Kim, Kye-Hyun
    • Journal of the Korean Association of Geographic Information Studies
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    • v.9 no.2
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    • pp.227-238
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    • 2006
  • Line density index(LDI) was developed to quantify a densely isothermal line rate as standard index in the ocean environment. Theoretical background on the LDI development process restricting index range 0 to 100 was described. And validation test was done for the LDI application condition that total line length is not greater than 1/10 of unit area. NOAA SST(Sea Surface Temperature) data were used for the experimental application of LDI in the South Sea of Korea. Using GIS, $0.1^{\circ}C$ isothermal lines were linearized as vector data form SST raster data, and unit area were built as polygon data. For the LDI calculation, spatial overlapping(line in polygon) was implemented. To analyze the effect of unit area size for the LDI distribution, two cases of unit area size were designed and descriptive statistics was calculated including performing normality test. The results showed no change of LDI's essential characteristics such as mean and normality except for the range of value, variance and standard deviation. Accordingly, it was found that complex structure of thermal front and even smaller scale of front width than unit area size could influence on the LDI distribution. Also, correlation analysis performed between LDI and difference of temperature(${\Delta}T^{\circ}C$), and horizontal thermal gradient(${\Delta}T^{\circ}C/km$) on the front was obtained from linear regression model. This obtained value was compared with the results from previous researches. Newly developed LDI can be used to compare the thermal front regions changing spatio-temporally in the ocean environment using absolute index value. It is considered to be significant to analyze the relationship between thermal front and marine environment or front and marine organisms in a quantitative approach described in this study.

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Synecological Study of the Forest Vegetation in Mt. Naeyeon, Pohang City, Korea - Focusing on the Southern Area - (내연산 산림식생에 대한 군락생태학적 연구 - 남쪽 지역을 중심으로 -)

  • Kim, Hak-Yun;Kim, Jun-Soo
    • Korean Journal of Environment and Ecology
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    • v.31 no.3
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    • pp.318-328
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    • 2017
  • In order to provide basic data for the ecological management of forest vegetation in Southern Naeyeon Mountains, A total of 149 sample plots were selected and vegetation survey was carried out by the phytosociological method of the ZM school to classify vegetation types and to grasp ecological characteristics. The forest vegetation was divided into 10 types in terms of species composition, and had a unit hierarchy of 2 community groups, 4 communities, 6 sub-communities and 6 variants. A total of 19 types of physiognomic vegetation were identified based on uppermost dominant species, of which 18 were natural vegetation and 1 was artificial vegetation. As a result of the analysis of the importance values of constituent species, Quercus mongolica, a potentially natural vegetation element, was found to be relatively more important in most stands than other species, and excluding the artificial interference, most of the areas except for some sites would be changed to Q. mongolica forest. In order to understand the spatial distribution of forest vegetation, 1/5,000 large-scale physiognomic vegetation map was created by the uppermost dominant species. As a result, natural vegetation accounted for 98.2%, the number of vegetation patches was 733 and the average area per patch 3.93ha.

Wavelet-Based Digital Watermarking Using Level-Adaptive Thresholding (레벨 적응적 이치화를 이용한 웨이블릿 기반의 디지털 워터마킹)

  • Kim, Jong-Ryul;Mun, Young-Shik
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.37 no.1
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    • pp.1-10
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    • 2000
  • In this paper, a new digital watermarking algorithm using wavelet transform is proposed. Wavelet transform is widely used for image processing, because of its multiresolution characteristic which conforms to the principles of the human visual system(HVS). It is also very efficient for localizing images in the spatial and frequency domain. Since wavelet coefficients can be characterized by the gaussian distribution, the proposed algorithm uses a gaussian distributed random vector as the watermark in order to achieve invisibility and robustness. After the original image is transformed using DWT(Discrete Wavelet Transform), the coefficients of all subbands including LL subband are utilized to equally embed the watermark to the whole image. To select perceptually significant coefficients for each subband, we use level-adaptive thresholding. The watermark is embedded to the selected coeffocoents, using different scale factors according to the wavelet characteristics. In the process of watermark detection, the similarity between the original watermark and the extracted watermark is calculated by using vector projection method. We analyze the performance of the proposed algorithm, compared with other transform-domain watermarking methods. The experimental results tested on various images show that the proposed watermark is less visible to human eyes and more robust to image compressions, image processings, geometric transformations and various noises, than the existing methods.

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Relations between the State and the Local in the Construction of Masan Export Processing Zone (마산수출자유지역의 형성을 둘러싼 국가-지방 관계에 대한 연구)

  • Park, Bae-Gyoon;Choi, Young Jin
    • Journal of the Korean Geographical Society
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    • v.49 no.2
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    • pp.113-138
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    • 2014
  • Despite the growing numbers of regional problems (e.g. conflicts between the state and localities, inter-local conflicts, etc.) associated with the state-led developmental projects, the Korean social sciences have been unable to offer satisfying explanations and solutions to the regional problems. This is mainly because the existing works, which have been taken captured by the assumptions of "methodological nationalism", significantly lack the socio-spatial understandings of the state actions and the relations between the state and localities, thereby seeing the issues of regional development mainly in terms of either the economic efficiency defined at the national scale, or the plan rationality of the national bureaucrats. With this problem orientation in mind, this paper aims to explore the ways in which the state and localities are interacting, conflicting and negotiating with one another through the mediation of the state-led developmental projects. Focusing on the developmental processes of Masan Export Processing Zone from the mid-1960s to the early 1970s, it examines the multi-scalar processes through which the state-led industrial complex developmental processes have been influenced by the complex and dynamic interactions among social forces and actors acting at diverse geographical scales (e.g. the global, national, local, urban, etc.). This analysis shows that the regional policies of the Korean developmental state were more heavily influenced by the interactions, contestations, and collaborations among social forces and actors, acting in and through the state, at various geographical scales, rather than by the economic and techno-bureaucratic rationality.

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