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Variation Analysis of Sea Surface Temperature in the East China Sea during Summer (동중국해에서 하계 표층수온의 변화 분석)

  • Park, GwangSeob;Lee, Taehee;Son, Young Baek
    • Korean Journal of Remote Sensing
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    • v.34 no.6_1
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    • pp.953-968
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    • 2018
  • In order to understand the change of surface water temperature in the East China Sea (ECS), this study analyzed the relationship between sea surface temperature (SST), air temperature (AT) and heat flux using satellite and model reanalysis data from 2003 to 2017. SST in the ECS showed the lowest (average : $13.72^{\circ}C$) in March and the highest (average : $28.12^{\circ}C$) in August. AT is highly correlated with SST and shows a similar seasonal change. In August, SST is higher than AT and then continuously higher than AT until winter. To analyze the change of the summer SST in the ECS, we used the SST anomaly value in August to classify the periods with positive (04', 06', 07', 13', 16', 17') and negative (03', 05', 08', 09', 10', 11', 12', 14', 15') values. Spatial similarity between the two periods indicates that SSTs are relatively larger variations in the northern part than in the southern part, and in the western part than in the eastern part in the study area. AT and net heat flux values also show similar changes with SST. However, the periods of the positive SST anomaly have the relatively increasing SST, AT and heat flux values compared to the periods of the negative SST anomaly in the summer season of the ECS. Although the change of SST in the summer season generally well correlates with AT, there were the periods when it was different from general trends between SST and AT (10', 12', 15', 16'). SST in August 2010 and 2012 decreased by $0.5^{\circ}C$ from AT. It suggests that the decreasing SST was considered to be caused by the effects of the typhoon passing through the study area. In August 2015, AT was relatively lower than SST (> $0.5^{\circ}C$), which is might be weakening of the East Asian Summer Monsoon. In August 2016, SST and AT show the highest values during the whole study periods, but SST is higher than AT (> $1^{\circ}C$). From satellite and heat flux data, the variations of SST have been shown to be relatively higher in the area of the expansion Changjiang Diluted Water (CDW) originated from the China coast. More research is needed to analyze this phenomenon, it is believed as not only the effect of rising AT but also the expansion of the low-salinity water.

Water Quality Monitoring of the Ecological Pond Constructed by LID Technique in Idle Space (유휴 공간에 LID 기법을 활용한 생태연못의 수질 모니터링)

  • Ahn, Chang-Hyuk;Song, Ho-Myeon;Park, Joon-Ha;Park, Jum-Ok;Park, Jae-Roh
    • Journal of Environmental Impact Assessment
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    • v.27 no.6
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    • pp.674-684
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    • 2018
  • The purpose of this study is to construct ecological pond using LID technique in order to create naturally comfortable community space in urban idle space. The specification of the ecological pond is $110m^2$ of surface area, $0.45{\pm}0.02m$ of average depth, and bed material is composed of gravel (diameter ${\leq}60mm$), sand (diameter ${\leq}2mm$) and bentonite. Rainfall and water depth monitoring were conducted to determine the annual characteristics of inflow of the water for the ecological pond, result of total rainfall was 1,287 mm and showed a seasonal imbalance that accounted for 71.3% (918 mm) during July to August, but the annual mean water depth was kept constant at $0.45{\pm}0.02m$ due to the secondary water source. Annual trends of basic water quality showed a significant changes according to the season, such as water temperature ($5.2{\sim}28.8^{\circ}C$), DO (5.0 ~ 13.8 mg/L), EC ($113{\sim}265{\mu}S/cm$). BOD, COD, TN, and TP in physicochemical water quality tended to increase after October, but the ion parameters such as $NH_3$ and $PO_4{^{3-}}$ were generally low. Phytoplankton indicators Chl-a and BGA (blue green algae) showed a sharp increase from July to August, and green algae (Selenastrum bibraianum, Pediastrum boryanum etc.) and filamentous blue green algae (Phormidium sp.) emerged as a dominant species. The ion parameters ($F^-$, $Na^+$, $K^+$, $Mg^{2+}$, $Ca^{2+}$) were strongly correlated with the $Cl^-$ as a conservative substance (R=0.70~0.97, p<0.05). Water quality was influenced by the ambient environment such as seasonal changes or rainfall, and it was closely related to fluctuation of the inflow of the water. In the future, it is necessary to consider ecological connections by referring to the characteristics surveyed in this study in order to effectively manage the water quality and biodiversity of the ecological pond in idle space.

The Need and Improvement Direction of New Computer Media Classes in Landscape Architectural Education in University (대학 내 조경전공 교육과정에 있어 새로운 컴퓨터 미디어 수업의 필요와 개선방향)

  • Na, Sungjin
    • Journal of the Korean Institute of Landscape Architecture
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    • v.49 no.1
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    • pp.54-69
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    • 2021
  • In 2020, civilized society's overall lifestyle showed a distinct change from consumable analog media, such as paper, to digital media with the increased penetration of cloud computing, and from wired media to wireless media. Based on these social changes, this work examines whether the use of computer media in the field of landscape architecture is appropriately applied. This study will give directions for new computer media classes in landscape architectural education in the 4th Industrial Revolution era. Landscape architecture is a field that directly proposes the realization of a positive lifestyle and the creation of a living environment and is closely connected with social change. However, there is no clear evidence that landscape architectural education is making any visible change, while the digital infrastructure of the 4th Industrial Revolution, such as Artificial Intelligence (AI), Big Data, autonomous vehicles, cloud networks, and the Internet of Things, is changing the contemporary society in terms of technology, culture, and economy among other aspects. Therefore, it is necessary to review the current state of the use of computer technology and media in landscape architectural education, and also to examine the alternative direction of the curriculum for the new digital era. First, the basis for discussion was made by studying the trends of computational design in modern landscape architecture. Next, the changes and current status of computer media classes in domestic and overseas landscape education were analyzed based on prior research and curriculum. As a result, the number and the types of computer media classes increased significantly between the study in 1994 and the current situation in 2020 in the foreign landscape department, whereas there were no obvious changes in the domestic landscape department. This shows that the domestic landscape education is passively coping with the changes in the digital era. Lastly, based on the discussions, this study examined alternatives to the new curriculum that landscape architecture department should pursue in a new degital world.

Analysis of the Characteristics of Korean Mushroom Exports (2008-2022) (한국의 버섯 수출의 특징 분석(2008~2022))

  • Woo-Sik Jo;Chang-Yun Lee;Young-Hyun Rew;Hun-Joong Kweon
    • Journal of Mushroom
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    • v.21 no.1
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    • pp.1-7
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    • 2023
  • This study addresses the current demand of the Korean mushroom export industry to establish an export strategy and governing policies.The enoki mushroom exports increased by 89% in 2009 and 23% in 2010, resulting in the largest export volume (17,163 tons) and export value ($26,292,000) being recorded in 2010. In contrast, exports in 2020 yielded only $18,525,000, which was 29% lower than that in 2010. In case of king oyster mushrooms, exports increased by 10% in 2012, 13% in 2013, and 2% in 2014, maintaining a moderate-growth trend. Moreover, Korea's mushroom exports are focused on a few specific countries. Enoki mushrooms accounted for more than 50% of the total exports to North America and Vietnam from 2012 to 2022, whereas king oyster mushrooms accounted for more than 50% of the total exports to Europe and North America (USA and Canada) from 2009 to 2022. Another characteristic trend in Korean mushroom exports is the diversification of export markets. The number of countries importing enoki mushrooms and king oyster mushrooms from Korea is increasing.

Assessing the Sensitivity of Runoff Projections Under Precipitation and Temperature Variability Using IHACRES and GR4J Lumped Runoff-Rainfall Models (집중형 모형 IHACRES와 GR4J를 이용한 강수 및 기온 변동성에 대한 유출 해석 민감도 평가)

  • Woo, Dong Kook;Jo, Jihyeon;Kang, Boosik;Lee, Songhee;Lee, Garim;Noh, Seong Jin
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.43 no.1
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    • pp.43-54
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    • 2023
  • Due to climate change, drought and flood occurrences have been increasing. Accurate projections of watershed discharges are imperative to effectively manage natural disasters caused by climate change. However, climate change and hydrological model uncertainty can lead to imprecise analysis. To address this issues, we used two lumped models, IHACRES and GR4J, to compare and analyze the changes in discharges under climate stress scenarios. The Hapcheon and Seomjingang dam basins were the study site, and the Nash-Sutcliffe efficiency (NSE) and the Kling-Gupta efficiency (KGE) were used for parameter optimizations. Twenty years of discharge, precipitation, and temperature (1995-2014) data were used and divided into training and testing data sets with a 70/30 split. The accuracies of the modeled results were relatively high during the training and testing periods (NSE>0.74, KGE>0.75), indicating that both models could reproduce the previously observed discharges. To explore the impacts of climate change on modeled discharges, we developed climate stress scenarios by changing precipitation from -50 % to +50 % by 1 % and temperature from 0 ℃ to 8 ℃ by 0.1 ℃ based on two decades of weather data, which resulted in 8,181 climate stress scenarios. We analyzed the yearly maximum, abundant, and ordinary discharges projected by the two lumped models. We found that the trends of the maximum and abundant discharges modeled by IHACRES and GR4J became pronounced as changes in precipitation and temperature increased. The opposite was true for the case of ordinary water levels. Our study demonstrated that the quantitative evaluations of the model uncertainty were important to reduce the impacts of climate change on water resources.

Future hydrological changes in Jeju Island based on CMIP6 climate change scenarios (CMIP6 기후변화 시나리오에 따른 제주도 지역의 미래 수문변화 전망)

  • Kim, Chul-Gyum;Cho, Jaepil;Lee, Jeong Eun;Chang, Sunwoo
    • Journal of Korea Water Resources Association
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    • v.56 no.11
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    • pp.737-749
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    • 2023
  • In this study, we analyzed the hydrological impacts of future climate change on Jeju Island using SSP-based climate change scenarios from 18 climate models and watershed modeling (SWAT-K). Despite discrepancies among climate models, we generally observed an increase in evapotranspiration due to rising future temperatures. Furthermore, a significant increase in runoff and recharge was noted due to increased precipitation. These increasing trends were particularly pronounced in the SSP5-8.5 scenario, and differences among GCM models became more significant in the late 21 century. When compared to the historical period (1981-2010), the projected changes for the far-future period (2071-2100) in the SSP5-8.5 scenario showed a 21.4% increase in precipitation, a 19.2% increase in evapotranspiration, a 40.9% increase in runoff, and a 16.6% increase in recharge on an annual average basis. On a monthly basis in the SSP5-8.5 scenario, precipitation was expected to increase by 24.5% in September, evapotranspiration by 34.1% in April, runoff by 58.1% in October, and recharge by 33.8% in September. To further assess projections based on extreme climate scenarios, we selected two models, CanESM5 and ACCESS-ESM1-5, which represented the maximum and minimum future precipitation forecasts, and compared the hydrological changes in the future scenarios. The results indicated that runoff and recharge rates were relatively higher in the CanESM5 model with the highest precipitation forecast, while evapotranspiration rates were higher in the ACCESS-ESM1-5 model with the lowest precipitation forecast. Based on the climate change scenarios used in this study, the overall available water resources on Jeju Island are more likely to increase. However, since results vary by season and region depending on the climate model and scenario, it is considered necessary to conduct a comprehensive analysis and develop response measures using various scenarios.

Impact of Physical and Vegetation Patterns on Parks Environment: A Case Study of Gusan Neighborhood Park, South Korea (도심산림녹지의 식생 및 물리적 구조에 따른 숲 내부 미기상 변화 연구)

  • Kim, Jeong-Ho;Choi, Won-Jun;Lee, Sang-Hoon;Lee, Myung-Hun;Yoon, Yong-Han
    • Korean Journal of Environment and Ecology
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    • v.34 no.5
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    • pp.425-435
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    • 2020
  • This study aims to investigate the impact of the physical structure, such as altitude, slope gradient, slope direction, and topographical structure, and the vegetation pattern, such as existing vegetation, diameter of breast height (DBH), and crown density, on climate. The analysis results showed the significant difference in relative humidity, wind speed, and solar radiation at varying altitudes, the significant difference in all climate factors except for the wind speed at varying slope gradient, and significant difference in temperature and relative humanity at varying slope direction. The topographic structures were divided into valleys, slopes, and ridges. They were found to differ in relative humidity. However, the differences between constant trends and types were found to be insignificant concerning temperature, wind speed, and solar radiation. Significant differences in temperature, relative humidity, and wind speed were recorded with changing existing vegetation. The DBH showed a significant difference in temperature, wind speed, and solar radiation. The crown density showed a significant difference in temperature and solar radiation. The result of the relationship analysis for the analysis of the effect of vegetation pattern and physical structure on the meteorological environment showed that temperature was affected by slope gradient, slope direction, DBH, and crown density. The relative humidity was correlated with the altitude, slope gradient, slope direction, and topological structure in physical structure and the existing vegetation and crow density in vegetation pattern. The wind speed was correlated with the altitude, existing vegetation, and DHB, and the solar radiation was correlated with the slope gradient, DHG, and crown density. The crown density was the most overall significant factor in temperature, relative humidity, and solar radiation, followed by the slope gradient. DBH was also found to be highly correlated with temperature and solar radiation and significantly correlated with wind speed, but there was no statistically significant correlation with relative humidity.

A Study on Fast Iris Detection for Iris Recognition in Mobile Phone (휴대폰에서의 홍채인식을 위한 고속 홍채검출에 관한 연구)

  • Park Hyun-Ae;Park Kang-Ryoung
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.43 no.2 s.308
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    • pp.19-29
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    • 2006
  • As the security of personal information is becoming more important in mobile phones, we are starting to apply iris recognition technology to these devices. In conventional iris recognition, magnified iris images are required. For that, it has been necessary to use large magnified zoom & focus lens camera to capture images, but due to the requirement about low size and cost of mobile phones, the zoom & focus lens are difficult to be used. However, with rapid developments and multimedia convergence trends in mobile phones, more and more companies have built mega-pixel cameras into their mobile phones. These devices make it possible to capture a magnified iris image without zoom & focus lens. Although facial images are captured far away from the user using a mega-pixel camera, the captured iris region possesses sufficient pixel information for iris recognition. However, in this case, the eye region should be detected for accurate iris recognition in facial images. So, we propose a new fast iris detection method, which is appropriate for mobile phones based on corneal specular reflection. To detect specular reflection robustly, we propose the theoretical background of estimating the size and brightness of specular reflection based on eye, camera and illuminator models. In addition, we use the successive On/Off scheme of the illuminator to detect the optical/motion blurring and sunlight effect on input image. Experimental results show that total processing time(detecting iris region) is on average 65ms on a Samsung SCH-S2300 (with 150MHz ARM 9 CPU) mobile phone. The rate of correct iris detection is 99% (about indoor images) and 98.5% (about outdoor images).

Effct of Species and Tedding Frequency on the Quality of Annual Legume Hay in Spring (초종 및 반전횟수가 봄철 일년생 콩과목초 건초의 품질에 미치는 영향)

  • Kim, J.D.;Kwon, C.H.;Kim, H.J.;Kim, M.G.
    • Journal of Animal Science and Technology
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    • v.46 no.3
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    • pp.451-458
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    • 2004
  • No comprebensive forage quality of annual legumes harvested and cured in spring has been conducted in Korea. Therefore, this experiment was carried out to gain information on the quality of crimson clover (Trifolium incarnatum L.), bolta baIansa clover(Trifolium ba/anansae L.), and persian c1over(Trifolium resupinatum L.) during field curing in spring. The dry matter content of crimson clover at harvest was 24.7%, while bolta balansa and persian clovers had 20.4 and 18.8%, respectively. The moisture content of persian clover was low at the final curing day. But All species took 4 days to reach moisture content under 20%Tedding frequency did not affect moisture content, but consisten trends were also observed during the field curing. Persian clover tended to show a higher leaf-stem ratio than crimson and bolta balansa clovers on dry matter basis. Crude protein of persian clover(19.5%) was higher than other legumes. The percentage of erode protein was decreased from 17.8 to 16.5% as tedding frequency often did. Neutral detergent fiber(NDF) and acid detergent fiber(ADF) contents of persian clover were lower than those of other legumes. From the comparison among tedding frequency, NDF and ADF contents of three times were higher than those of one and two times. Relative feed value(RFV) of persian clover hay was the highest(178) and classified as Grade Prime in forage quality standard. Crimson and bolta balansa clovers in the RFV were also high quality as Grade 1 in forage quality standard. The RFV of legume hay was decreased from 150 to 140 as tedding frequency often did Results of the experiment indicate that hay quality of persian clover was higher than other clovers. And this is due to high leaf and stem content, hollow stem and late maturity stage. Then tedding frequency in annual legume can be teded by two times for quality.

Effects of Storage Form and Period of Refrigerated Rice on Sensory Properties of Cooked Rice and on Physicochemical Properties of Milled and Cooked Rice (냉장 쌀의 저장 형태 및 기간에 따른 쌀밥의 관능적 특성)

  • Lee, Ju-Hyun;Kim, Sang-Sook;Suh, Dong-Soon;Kim, Kwang-Ok
    • Korean Journal of Food Science and Technology
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    • v.33 no.4
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    • pp.427-436
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    • 2001
  • The effects of storage form (paddy and milled rice) and storage period (1, 2, and 3 years) of rice at low temperature $(4^{\circ}C)$ on physicochemical properties of milled and cooked rice and sensory characteristics of cooked rice were investigated. The proximate compositions except moisture content of rice decreased as the storage period increased. Water binding capacity, solubility and swelling power of rice flour decreased with the extended storage period. In the amylogram, the initial pasting temperature, paste viscosity and breakdown of paddy rice flour slurry decreased after 2 years of storage. Moisture content of cooked rice increased while the amount of water evaporated during cooking decreased. These trends were obvious with the longer storage period. Lightness and yellowness of cooked rice were greatly changed after 3 years of storage, regardless of storage form. Texture profile analysis of cooked rice by Texture Analyzer revealed that hardness, fracturability, gumminess were gradually increased while adhesiveness decreased as the storage period of rice increased. A trained panel found that color intensity, intactness of grains, rancid flavor, rice bran flavor, wet cardboard flavor, hardness and chewiness of cooked rice increased with the longer storage period. However, glossiness, transparency, plumpness, puffed corn flavor, dairy flavor, boiled egg white flavor, sweet taste, adhesiveness to lips, smoothness and inner moisture decreased with the extended storage period up to 3 years. Instrumental hardness was highly correlated with sensory hardness.

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