• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3B
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• pp.261-270
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• 2008

Even though there is a great deal of progress in a numerical method of high caliber like SPH, it is very rarely deployed in a water resources community. Despite the great stride in computing environment, depth averaged approach like a nonlinear shallow equation is still efficient tool for flood routing in large watershed, but it can give some misleading information like the inundation height of flood. In this rationale, we numerically simulate the flow into the dry channel, dry channel with an obstacle triggered by the collapse of a two dimensional water column using SPH (Smoothed Particle Hydrodynamics) in order to boost the application of numerical method of high caliber like SPH in a water resources community. As a most severe test of the robustness of SPH, we also carry out the simulation of the flow through a clearance into the wet channel driven by the rapid removal of a water gate. As a hydrodynamic model, we used the Navier-Stokes equation, a numerical integration of which was carried out using SPH. To verify the validity of newly proposed numerical model, we compare the numerically simulated flow with the others in the literature mainly from VOF and MAC, and hydraulic experiments by Martin and Moyce (1952), Koshizuka et al. (1995) and Janosi et al. (2004). It was shown that agreements between the numerical results in this study and hydraulic experiments are remarkable.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.3
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• pp.646-669
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• 2004

By treating skin diseases with Hyungsang medicine and reviewing the clinical cases of them through classifying skin diseases into general care and into Hyungsang medical care, the writer came to the conclusion as followings. The skin is a house of Kyungnak, and it' s a place which Ki comes in and out, which human body controls conditions of his physiological function and which doctors can make a diagnosis from seeing it. The skin is subject to lung and large intestine in the point of organ, but in the point of movement, to spleen and stomach. Skin diseases come from unbalance of Ki and Hyul, mostly from fever in blood and also from Dam, Wind, Dampness and Dryness because of including fire. Generally skin diseases are treated according to classifying into distinctive symptoms, region, cause or time being occurred, and concomitant symptoms. After being divided into man and woman, age and youth, fatness and leanness, Jung Ki Shin Hyul type, visceral figures, Yukkyung shapes on Hyungsang medicine method, the remedy of skin diseases which is combined common meditation with Hyungsang medical method is efficacious. In distinguishing into man and woman, age and youth, man gets sick mainly by drinking liquor and exhausting Jung, woman is taken ill generally by indigestion and Damwha, especially by drinking liquor. Young child gets ill mostly from inherent weakness, but in many cases he is occurred by disturbed digestion, so he must be taken care of ingesting food. The aged becomes ill from weakening, so he must be treated according to reasons of diseases. To fatness and leanness, skin diseases are showed symptoms by weakened Yang, insufficient Yin or excess fever on the theory of upper and lower parts, by unbalance of Ki and Hyul on the theory of left and right, by Dryness and Dampness on the theory of front and rear and by insufficiency of vitality and combined fever on the theory of inside and outside. Therefore doctors must cure the symptoms according to the theory of upper and lower, left and right, front and rear and inside and outside. In type of Jung Ki Shin Hyul, the balances between Jung-Hyul and Shin-Ki are important points. Concretely Jung type comes to easily shortage of Jung or gathering abnormally Dampness and Dam, Ki type is easy to make a mass with Ki or to be deficient of Ki, Shin type comes to press seven emotions togather or to be insufficient of Yin and fever inside, and Hyul type is inclined to be deficient of Hyul and to become feverish or to be deficient of Ki. Therefore on the ground of the above reasons skin diseases come into existence. Inclusively in Jung-Hyul type , Ki must be moved on the base of full Jung-Hyul, so Wukmijiwhangtang or Samultang is prescribed basically. In Shin-Ki type , Jung-Hyul is saved on the base of moving Ki, so Hyangsosan or Yijintang is the proper prescription. Considering the visceral figures, doctors judge for diagnosis and remedy by putting together the elements, that is, great and small sizes of a set of features (eye, ear, mouth, nose), color and temper. The yukkyung types are classified according to many or few of Ki-Hyul, and then skin diseases appear by being inclined toward one side between Ki and hyul, or among the six atmospheric elements(wind, cold, heat, dampness, dryness, and fire). Especially because Yangmyung type is full of much Ki and Hyul, and also has much fever in stomach, he gets skin symptoms frequently. So his prescription is based on taking off fever in stomach, and also he must be careful about regimen certainly.

• Korean Journal of Ecology and Environment
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• v.33 no.3 s.91
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• pp.222-229
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• 2000

Spatial and temporal variation of phosphorus in response to intensity of summer monsoon was evaluated in Taechung Reservoir during 1993${\sim}$1994. Total phosphorus (TP) averaged 31 ${\mu}$g/l during the study and varied from 6 to 197 ${\mu}$g/l. Concentrations of TP were highest in the headwaters during the monsoon of July${\sim}$August 1993, and these values were mainly made of particulate P and were closely associated (R$^{2}$=0.74, p<0.001) with high inorganic suspended solids (NVSS). In-lake TP in the headwaters was mainly influenced by the watershed runoff and declined toward the dam. Values of TP downlake was only one-fifth of the peak in the headwaters and had no correlation with NVSS. In 1994, inlake TP was markedly lower relative to 1993 and showed low spatial and temporal variation. Maximum TP during monsoon 1994 in the headwaters and mid-lake was 72% and 52% lower, respectively, than in those two zones in 1993 whereas TP downlake was similar between the two years. These results suggest that temporal variation downlake is much less influenced by seasonal inflow compared to the haedwaters. In 1993, mean TP before fall overturn, based on average value for all sites, was significantly (t=5.99, p<0.001) greater than the mean after fall overturn, whereas in 1994 mean TP after fall overturn (32 ${\mu}$g/l) was greater. This outcome indicates that in 1993 major P-input originated from the external source from the watershed during the intense monsoon, whereas in 1994 internal processes dominated during the weak monsoon. Overall data suggest that annual budget of inlake P is regulated by intensity of the summer monsoon, and phosphorus data measured at single site near the dam or headwater zone may not be represent seasonal trends of the system due to large spatial variation of Taechung Reservoir.

• Korean Journal of Ecology and Environment
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• v.39 no.2 s.116
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• pp.271-283
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• 2006

A systematic water quality survey was conducted in August, 2005 for a drinking water supply reservoir (the Jeolgol reseuoir located in an island), which is at an early stage of impoundment, to investigate the causes of water color deterioration of the reservoir and the clogging of filter beds of a water treatment plant. The reservoir shape was simple and its average depth was 5.5 m, increasing from upreservoir toward the downreservoir end near the dam. Dissolved oxygen (DO) and chloropllyll-a (chi-a) showed a large variation while water temperature had a smaller range. Transparency ranged from 0.6 to 0.9 m (average 0.7 m). The average value of turbidity was 9.3 NTU, ranging from 8.0 ${\sim}$ 12.1 NTU. The transparency and the turbidity appear to be affected by a combination of biological and non-biological factors. The poor transparency was explained by an increase of inorganic colloids and algal bloom in the reservoir. The blockage of the filter bed was attributed to the oversupply of phytoplanktons from the reservoir. The range and the average concentration of chi-a within the reservoir were 31.6 ${\sim}$ 258.9 ${\mu}g\;L^{-1}$, 123.6 ${\mu}g\;L^{-1}$ for the upper layer, and 17.0 ${\sim}$ 37.4 ${\mu}g\;L^{-1}$, 26.5 ${\mu}g\;L^{-1}$ for the bottom layer, respectively. A predominant species contributing the algal bloom was Dinophyceae, Peridinium bipes f. occultatum. The distribution of Peridinium spp. was correlated with chi-a concentrations. The standing crop of phytoplankton was highest in the upreservoir with $8.5\;{\times}\;103\;cells\;mL^{-1}$ and it decreased toward the downresevoir. Synedra of Bacillariophyceae and Microcystis aeruginosa of Cyanophyceae appeared to contribute to the algal bloom, although they are not dominated. It is mostly likely that sloped farmlands located in the watershed of the reservoir caused water quality problems because they may contain a significant amount of the nutrients originated from fertilizers. In addition, the aerators installed in the reservoir and a shortage of the inflowing water may be related to the poor water quality. A long-term monitoring and an integrated management plan for the water quality of the watersheds and the reservoir may be required to improve the water quality of the reservoir.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.38 no.2
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• pp.60-76
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• 2020

The purpose of this study was to examine the spatial and visual arrangement characteristics of Imsil Yi Ung-jae's old house's spatial and visual aspects in order to discover the value of landscape and traditional house garden. The results of this study are as follows. Dongchon-village in Dundeok-ri, where old house is located, is a typical form of with "Back to the mountain and facing the water(背山臨水)", and is located in the north of the three streams of water, forming a Jeonchaghugwan(前窄後寬). Dongchon Village, which has a traditional scenic spot between Danguidae(丹丘臺) and Samgyeseokmun(三溪石門), is understood to be the main street of Nojeokbong Peak and Gyegwanbong Peak, which is Ansan(案山), where the "A centipede flying in the sky(飛天蜈蚣形)". Yi Ung-jae's old house is the oldest existing high-priced house in the North Jeolla region and the closing price of a royal family of the Joseon Dynasty, which was arranged by Chunseongjeong(春城正), Yi Dam-son(李聃孫) in the mid-16C. The Japanese Invasion of Korea in 1592 and Japanese colonial era, the loyalty of the gate quarters, the filial piety of the gate quarters, and the faithfulness of the tablet(扁額) and Juryeons(柱聯) are enough to contribute to the rise of the value of a physical house. The men's quarters(Sarangchae), which are placed on a high-pocket or a layout without going against the sloping terrain, have the effect of making the distance as far as possible, enhancing its dignity and hierarchy as a royal building. In addition, the entrance to the main quarters(Anchae) through the four pillar gates(四柱門), the extensive support and the appropriation of the Chaewon(vegetable garden), and the official base for the Anchae are very unique compared to the general nobility. However, in the context of the postwar relationship, the shrine seeks to realize Confucian ideals while harmonizing with nature by arranging wide sponsorships around it. On the other hand, it is confirmed that there was a pond in the form of a circle in a square(方池圓島型) with a relatively large area, which is now disturbed and damaged. Written by the high priced planting species are sponsored pine trees, hackberry, persimmon trees, Japanese apricot flower, Ohmomiji, and plum tree in the side garden, as well as cotyledon trees in the outside garden. However, although flower bed(花階), which is built on the stone axis, is a place that clearly shows the expensive garden, it seems to have lost the texture of the plant due to the extremely high variety of species and the splendor that does not match the plant landscape of the flower world. Yi Ung-jae's old house is highly valuable as it is a portrait house of a prince of the blood in the mid-Joseon Dynasty. Based on these findings, this study proposed a plan to improve the management of high prices that could be met.

• Korean Journal of Remote Sensing
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• v.40 no.2
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• pp.229-241
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• 2024

With the advancement of big data processing technology using cloud platforms, access, processing, and analysis of large-volume data such as satellite imagery have recently been significantly improved. In this study, the Change Detection Method, a relatively simple technique for retrieving soil moisture, was applied to the backscattering coefficient values of pre-processed Sentinel-1 synthetic aperture radar (SAR) satellite imagery product based on Google Earth Engine (GEE), one of those platforms, to estimate the surface soil moisture for six observatories within the Yongdam Dam watershed in South Korea for the period of 2015 to 2023, as well as the watershed average. Subsequently, a correlation analysis was conducted between the estimated values and actual measurements, along with an examination of the applicability of GEE. The results revealed that the surface soil moisture estimated for small areas within the soil moisture observatories of the watershed exhibited low correlations ranging from 0.1 to 0.3 for both VH and VV polarizations, likely due to the inherent measurement accuracy of the SAR satellite imagery and variations in data characteristics. However, the surface soil moisture average, which was derived by extracting the average SAR backscattering coefficient values for the entire watershed area and applying moving averages to mitigate data uncertainties and variability, exhibited significantly improved results at the level of 0.5. The results obtained from estimating soil moisture using GEE demonstrate its utility despite limitations in directly conducting desired analyses due to preprocessed SAR data. However, the efficient processing of extensive satellite imagery data allows for the estimation and evaluation of soil moisture over broad ranges, such as long-term watershed averages. This highlights the effectiveness of GEE in handling vast satellite imagery datasets to assess soil moisture. Based on this, it is anticipated that GEE can be effectively utilized to assess long-term variations of soil moisture average in major dam watersheds, in conjunction with soil moisture observation data from various locations across the country in the future.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.3
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• pp.143-149
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• 2018

Recently, due to the large-scale damage of natural disasters caused by global climate change, a monitoring system applying remote sensing technology is being constructed in disaster areas. Among remote sensing platforms, the drone has been actively used in the private sector due to recent technological developments, and has been applied in the disaster areas owing to advantages such as timeliness and economical efficiency. This paper deals with the development of a preprocessing system that can map the drone image data in a near-real time manner as a basis for constructing the disaster monitoring system using the drones. For the research purpose, our system is based on the SURF algorithm which is one of the computer vision technologies. This system aims to performs the desired correction through the feature point matching technique between reference images and shot images. The study area is selected as the lower part of the Gahwa River and the Daecheong dam basin. The former area has many characteristic points for matching whereas the latter area has a relatively low number of difference, so it is possible to effectively test whether the system can be applied in various environments. The results show that the accuracy of the geometric correction is 0.6m and 1.7m respectively, in both areas, and the processing time is about 30 seconds per 1 scene. This indicates that the applicability of this study may be high in disaster areas requiring timeliness. However, in case of no reference image or low-level accuracy, the results entail the limit of the decreased calibration.

• Journal of Life Science
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• v.23 no.6
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• pp.804-811
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• 2013

Melanopsin is an opsin-like photopigment found in the small proportion of photosensitive ganglion cells of the retina. It is involved in the regulation of the synchronization of the circadian cycle as well as in the control of pupillary light reflex. The purpose of the present study is to investigate whether melanopsin is also expressed in the other areas of the central visual system outside the retina. We have studied the distribution and morphology of neurons containing melanopsin in the mouse visual cortex with antibody immunocytochemistry. Melanopsin immunoreactivity was mostly present in neuronal soma, but not in nuclei. We found that melanopsin was present in a large subset of neurons within the adult mouse visual cortex with the highest density in layer II/III. In layer I of the visual cortex, melanopsin-immunoreactive (IR) neurons were rarely encountered. In the mouse visual cortex, the majority of the melanopsin-IR neurons consisted of round/oval cells, but was varied in morphology. Vertical fusiform and pyramidal cells were also rarely labeled with the anti-melanopsin antibody. The labeled cells did not show any distinctive distributional pattern. Some melanopsin-IR neurons in mouse visual cortex co-localized with nitricoxide synthase, calbindin and parvalbumin. Our data indicate that melanopsin is located in specific neurons and surprisingly widespread in visual cortex. This finding raises the need of the functional study of melanopsin in central visual areas outside the retina.

• Journal of the Korean Association of Geographic Information Studies
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• v.20 no.3
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• pp.12-26
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• 2017

The objective of this study was to develop a runoff analysis system of the Nakdong River watershed using the GRM (Grid-based Rainfall-runoff Model), a physically-based distributed rainfall-runoff model, and to assess the system run time performance according to Microsoft Azure VM (Virtual Machine) settings. Nakdong River watershed was divided into 20 sub-watersheds, and GRM model was constructed for each subwatershed. Runoff analysis of each watershed was calculated in separated CPU process that maintained the upstream and downstream topology. MoLIT (Ministry of Land, Infrastructure and Transport) real-time radar rainfall and dam discharge data were applied to the analysis. Runoff analysis system was run in Azure environment, and simulation results were displayed through web page. Based on this study, the Nakdong River real-time runoff analysis system, which consisted of a real-time data server, calculation node (Azure), and user PC, could be developed. The system performance was more dependent on the CPU than RAM. Disk I/O and calculation bottlenecks could be resolved by distributing disk I/O and calculation processes, respectively, and simulation runtime could thereby be decreased. The study results could be referenced to construct a large watershed runoff analysis system using a distributed model with high resolution spatial and hydrological data.

• Journal of the Korean Geotechnical Society
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• v.31 no.1
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• pp.5-14
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• 2015

Seabed may undergo large excess pore water pressure in the case of long duration of high wave loading. This excess pore water pressure may reduce effective stress and, consequently, the seabed may liquefy. Thus, it is necessary to develop a numerical technique which can precisely evaluate the dynamic response of seabed due to wave action. In this study, a new numerical technique named mixed model (2D NIT & FLIP models) was proposed. The dynamic wave pressure and water flow velocity acting on the boundary between seabed and the wave field was estimated using 2D-NIT model. This result was used as input data in FLIP program for investigation of dynamic response of seabed. To secure the reliability of the mixed model, the numerical analysis results of the mixed model were compared with Yamamoto's solution and Chang's experiment results. The comparison results indicated that there were some differences between them, but the general trend of the effective stress increment and the excess pore water pressure along the depth of seabed was similar to each other. Thus, this study clearly supports the plausibility of the numerical analysis of the mixed model.