• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.4D
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• pp.561-567
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• 2008

In this study, shoreline change was analyzed by RTK-GPS and advanced airborne LiDAR survey. For extraction of coastline, first of all, tide correction was conducted at all RTK-GPS points through the comparing with the corresponding tidal height, and cross section providing coastline was produced using Autocad Civil3D program. Comparing with two results of RTK-GPS (first, 29 Aug 2007; second, 6 Oct 2007) surveys, coastline of the first result had been decreased about 21m compare with that of the second. And it was also demonstrated that the length of coastline by the first RTK-GPS was 15m shorter than that by the airborne LiDAR survey (Dec. 2006). In addition, we recoquized that the erosion appeared in the top right-hand (dock area); the sediment in the bottom left-hand (Chosun beach area) of the Haeundae beach. As a result, therefore, it was learned that artificial sand filling for beach open and natural effects such as a typhoon, current drift, wind direction gave cause for area changes and coastline.

• The Korean Journal of Petroleum Geology
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• v.10 no.1_2 s.11
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• pp.10-17
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• 2004

The Doowoo-ri tidal flat in the southwestern Korean coast is a typical open-coast tidal flat which has no barriers in the offshore such as barrier island and sand bars. The difference of induced wave energy with seasons is affected directly on the distribution of surface sediment and the formation of sedimentary structures because the sedimentation by wind wave is relatively much important element in this open-coast tidal flat. This open-coast tidal flat can be classified into tidal beach, intertidal flat and lower mudflat according to the pattern of geomorphology and sediment type. The intertidal flat can be again divided into 3 types: sand flat, mixed flat and mud flat based on the primary sedimentary structure and sand/mud ratio. Doowoori tidal flat shows a seasonal change in the surface sedimentary facies based on sediment composition and primary sedimentary structure. The change is closely related to the direction and magnitude of monsoon wind and also to storm frequency. In winter and spring, when northwesterly wind is most dominant and strong and also storms are common, sand-flat facies is largely distributed on the intertidal flat, whereas mud-flat facies is most dominant during summer when weak southeasterly wind is common. In the fall season, mixed-flat facies is dominant on the flat. The Doowoori intertidal flat is covered by mud sediment which is ca. 20 cm in thickness in summer season. In winter season, surface sediment is changed from mud to sand because the summer mud is mostly eroded by strong wave action. Can-core peels in the intertidal flat show that parallel laminated mud or sand/mud and climbing ripple cross-laminated sandy silt are dominant on the upper intertidal flat $(0-1.3 {\cal}km)$ during summer season. On the other hand, on lower intertidal flat $(1.7-2.3 {\cal}km)$, dominant sedimentary facies is homogeneous mud. In winter, it is changed into parallel laminated and ripple cross-laminated sand facies.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.1
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• pp.21-33
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• 2013

The purpose of this study is to find applicabilities of human bioclimatic maps, using human thermal sensation(comfort) in summer, with microclimatic in situ data and computer simulation results at the study site of downtown Daegu. This includes the central business district(CBD) area and two urban parks, the Debt Redemption Movement Memorial Park and the 2.28 Park, for urban and landscape planning and design. Climatic data and urban setting information for the analysis of human thermal sensation were obtained from in situ measurement and the geographic information system data. As a result, the CBD had higher air temperature than the parks when the wind speed was low. Relative humidities were opposite to the air temperature. Especially, same directional streets with local wind direction had lower air temperature than streets perpendicular to the wind direction. The most important climatic variable of human thermal sensation in summer was direct beam solar radiation. Also, creating shadow areas would be the most relevant method for modifying hot thermal environments in urban areas. The most effective method of creating shadow patterns was making a tree shadow over a pergola, and the second best one was making a tree shadow on the front of north directional building walls. Moreover, how to plant trees for creating shadow patterns was important as well as what kind of trees should be planted. The results of human thermal sensation were warm to very hot at sunny areas and neutral to warm at shaded ones. At the sunny areas, wide, squared shape areas had a little bit higher thermal sensation than those of narrow streets. The albedo change of building walls 0.15 and ground surface 0.1 could change 1/6 of a sensation level at the shaded areas and 1/3 at the sunny ones. These microclimatic approaches will be useful to find appropriate methods for modifying thermal environments in urban areas.

• Journal of the Korean Association of Geographic Information Studies
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• v.21 no.1
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• pp.115-127
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• 2018

This study aims to propose management strategies of ventilation paths for improving urban thermal environments. For this purpose, Gimhae-si in Gyeongsangnamdo was selected as a study area. We analyzed hot spots and cool spots in Gimhae by using Landsat 8 satellite image data and spatial statistical analysis, and finally derived the vulnerable areas to thermal environment. In addition, the characteristics of ventilation paths including wind direction and wind speed were analyzed by using data of the wind resource map provided by Korea Meteorological Administration. As a result, it was found that a lot of hot spots were similar to those with weak wind such as Jinyoung-eup, Jillye-myeon, Juchon-myeon and the downtown area. Based on the analysis, management strategies of ventilation paths in Gimhye were presented as follows. Jinyoung-eup and Jillye-myeon with hot spot areas and week wind areas have a strong possibility that hot spot areas will be extended and strengthened, because industrial areas are being built. Hence, climate-friendly urban and architectural plans considering ventilation paths is required in these areas. In Juchon-myeon, where industrial complexes and agricultural complexes are located, climate-friendly plans are also required because high-rise apartment complexes and an urban development zone are planned, which may induce worse thermal environment in the future. It is expected that a planning of securing and enlarging ventilation paths will be established for climate-friendly urban management. and further the results will be utilized in urban renewal and environmental planning as well as urban basic plans. In addition, we expect that the results can be applied as basic data for climate change adaptation plan and the evaluation system for climate-friendly urban development of Gimhye.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.187-190
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• 2006

In the present study, effects of tree-stream turbulence and surface trip wire on the flow past a sphere at $Re\;=\;0.4\;{\times}\;10^5\;{\sim}\;2.8\;{\times}\;10^5$ are investigated through wind tunnel experiments. Various types of grids are installed upstream of the sphere in order to change the tree-stream turbulence intensity. In the case of surface trip wire, 0.5mm and 2mm trip wires are attached from $20^{\circ}\;{\sim}\;90^{\circ}$ at $10^{\circ}$ interval along the streamwise direction. To investigate the flow around a sphere, drag measurement using a load cell, surface-pressure measurement, surface visualization using oil-flow pattern and near-wall velocity measurement using an I-type hot-wire probe are conducted. In the variation of free-stream turbulence, the critical Reynolds number decreases and drag crisis occurs earlier with increasing turbulence intensity. With increasing Reynolds number, the laminar separation point moves downstream, but the reattachment point after laminar separation and the main separation point are fixed, resulting in constant drag coefficient at each free-stream turbulence intensity. At the supercritical regime, as Reynolds number is further increased, the separation bubble is regressed but the reattachment and the main separation points are fixed. In the case of surface trip wire directly disturbing the boundary layer flow, the critical Reynolds number decreases further with trip wire located more downstream. However, the drag coefficient after drag crisis remains constant irrespective of the trip location.

• Water for future
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• v.27 no.2
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• pp.73-83
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• 1994

The unproper development of the nearshore zone can enhance the diffusion of pollutant in the nearshore zone resulting in unbalanced sediment budget of beach which causes alteration of beach topography. Therefore, it is required to predict the effects of the envirnmental change quantitatively. In this paper, the depth-averaged and time-averaged energy balance equation is selected to acount for the wave transformation such as refraction, shoaling effect, the surf zone energy disipation, wave breaking index and bore, due to wave breaking in the shore region.(Numerical solutions are obtained by a finite difference method, ADI and Upwind. For the calculation of the wave-induced current, the unsteady nonlinear depth-averaged and time-averaged governing equation is derived based on the continuity and momentum equation for imcompressible fluid.) Numerical solutions are obtained by finite difference method considering influences of factors such as lateral mixing coefficient, bed shear stress, wave direction angle, wave steepness, wave period and bottom slope. The model is applied to the computation of wave transformation, wave-induced current and variation of mean water leel on a uniformly sloping beach.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.9
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• pp.6411-6418
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• 2015

To respond the climate change and environmental pollution, the studies on renewable energy policies are increasing. The renewable energy is a new growth engine technology represented by the green industry and green technology. At present, the investments for the renewable energy supply and technology development projects of three main strategy sectors such as sunlight, wind power and hydrogen fuel cell are implemented in our country, while they are still in the early stage, accordingly reducing those uncertainty for the research direction and investment fields is the most urgent issue among others. Thus, this study applied text mining method and multinominal topic model among the big data analysis methods on our country's newspaper articles concerning the renewable energy over the last 10 years, and then analyzed the core issues and global research trend, forecasting the renewable energy fields with the growth potential. It is predicted that these results of the study based on information and communication technology will be actively applied on the renewable energy fields.

• Atmosphere
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• v.31 no.4
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• pp.445-459
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• 2021

This study uses a cloud-resolving storm simulator (CReSS) to understand the individual effect of determinant meteorological factors on snowfall characteristics in the Yeongdong region based on the rawinsonde soundings for two snowfall cases that occurred on 23 February (Episode 1) and 13 December (Episode 2) 2016; one has a single-layered cloud and the other has two-layered cloud structure. The observed cloud and precipitation (snow crystal) features were well represented by a CReSS model. The first ideal experiment with a decrease in low-level temperature for Episode 1 indicates that total precipitation amount was decreased by 19% (26~27% in graupel and 53~67% in snow) compared with the control experiment. In the ideal experiment that the upper-level wind direction was changed from westerly to easterly, although total precipitation was decreased for Episode 1, precipitation was intensified over the southwestern side (specifically in terrain experiment) of the sounding point (128.855°E, 37.805°N). In contrast, the precipitation for Episode 2 was increased by 2.3 times greater than the control experiment under terrain condition. The experimental results imply that the low-level temperature and upper-level dynamics could change the location and characteristics of precipitation in the Yeongdong region. However, the difference in precipitation between the single-layered experiment and control (two-layered) experiment for Episode 2 was negligible to attribute it to the effect of upper-level cloud. The current results could be used for the development of guidance of snowfall forecast in this region.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.10
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• pp.1300-1305
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• 2020

Due to the simplicity of communication structure using RS-232 and RS-422, the majority ships have still adapted on these communication interfaces and have constructed their own communication network in the ship. NMEA-0183 is the one of standards for BNWAS(Bridge Navigational Watch Alarm System) and currently being used in many countries. BNWAS utilises diverse sensor devices, GPS, AIS and so on for monitoring the status of ships and their deployments and environmental information(temperature, humidity, wind speed/direction, water temperature/current etc…). This paper proposes the use of any image sensors in NMEA-0183 environment and verifies possibility with certain video qualities through the experiment results. Furthermore the paper gathers videos and monitors the change of their qualities depending on the number of NMEA messages on RS-232 communication link. Finally we make conclusion that our proposal is sufficiently appropriate for ship monitoring system in the NMEA-0183.

• Journal of Korean Medical classics
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• v.28 no.1
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• pp.111-125
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• 2015

Objectives : The objectives of this study is to provide the theoretical basis to cure and prevent mental disease by translating and considering Benshen chapter in LingShu. Methods : First, I translate the contents of "Benshen" chapter in LingShu paragraph by paragraph. Second, I consider the contents of Benshen chapter in LingShu. Third, after considering each paragraph of Benshen chapter in LingShu, I think the relation of each paragraph and picture to myself Benshen chapter. Results and Conclusions : 1. Heart(心) appeared in Benshen chapter mediates the action of 'JeongSinHonBaek(精神魂魄)' and 'UiJiSaRyeoJi(意志思虑智)'. 2. 'UiJiSaRyeoJi(意志思虑智)' appeared in Benshen chapter means the process of the maturity of thought. 'Jeong(精)' which has a 'water(水), sink(沈), silent(靜)' image gets involved in the development from 'Ui(意)' to 'Ji(志)', because its process means the thought is deepening. 'Hon(魂)' which has a 'wind(風), cloud(雲), change(變)' image gets involved in the development from 'Ji(志)' to 'Sa(思)', because its process means the change of the thought. 'Sin(神)' which has a 'fire(火), bright(明), move(動)' image gets involved in the development from 'Sa(思)' to 'Ryeo(慮)', because its process means the expansion the horizon of the cognition. 'Baek(魄)' which has a 'metal(金), firm(剛), decide (決)' image gets involved in the development from 'Ryeo(慮)' to 'Ji(智)', because its process means the wise response to real world. 3. If one is immersed in one emotion and cannot escape from it, the functional change of Gi(氣) due to its emotion harms five spirits which move in the opposite direction and causes mental physical symptoms and has a possibility to die in the season which inhibit each five organs. 4. Five spirits(五神) acts based on 'HyeolMaekYeongGiJeong(血脈營氣精)' and in the symtoms caused by deficiency and excess of five organ Gi(五藏氣), symptoms of liver and heart appear in emotion and symptoms of spleen lung kidney appear in body. 5. Benshen chapter highlights the importance of checking 'Sin(神)' and 'Gi(氣)' treating a patient with acupuncture and mentioning the importance of observing deficiency and excess of five organ Gi(五藏氣) in the last paragraph means 'Sin(神)' and 'Gi(氣)' are inseparably related.