• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.11
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• pp.1050-1059
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• 2005

Heat and $SF_6$ gas dispersions over a complex terrain were investigated using wind tunnel. The wind speed, temperature and concentration profiles were measured for the 1/1000 scale complicated terrain model in an Eiffel type boundary layer wind tunnel with test section of 2.5m in height and 4.5m in width. The scale model was mounted on the top of a plate which can rotate with respect to the approaching wind. Dispersion processes from a continuous emission source driven by various wind direction were investigated, including plume climbing over the steep up-slope of the mountain and down-spreading toward the lower level of the valley. Extensive dispersion experiment data (wind speeds and concentration profiles) were provided for verification and validation of dispersion models. Under the identical flow and emission conditions, the independently measured profiles of the temperature and $SF_6$ concentration showed an excellent agreement which ensured the credibility of the results.

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.2
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• pp.67-83
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• 2002

The coupled model (SMART) of dynamic meteorology model and particle dispersion model was developed. The numerical experiment on the relationship between change of land use and diffusion behavior in complex terrain was carried out using this model. It tried to investigate the change of particle diffusion behavior and local weather under the condition in which land-land breeze and sea breeze and mountain breeze intermingled. The numerical experiment results are as follows; 1) The more complicated local circulation field of the interaction of sea breeze, mountain breeze and Land -land breeze is formed. Then, the region circulation in which the urbanization is specific by location of the region is strengthened and is weakened. 2) Though in the region with dominant sea breeze, Land-land breeze does not appear directly, the progress of the sea wind to the inland is affected. 3) In the prediction of the air diffusion, emission high quality and accurate information of the emission site are important. That is to say, the dispersion predicting result which emission high quality and small error of the site perfectly vary for Land - land breeze in the effect may be brought about.

• Journal of The Korean Society of Agricultural Engineers
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• v.64 no.6
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• pp.13-23
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• 2022

The purpose of this study was to analyze the impact of greenhouse cultivation area and groundwater level changes due to the water curtain cultivation in the greenhouse complexes, which are mainly situated along rivers where water resources are easy to secure. The groundwater observation network in Miryang, Gyeongsangnam-do, located downstream of the Nakdong River, was selected for the study area. We classified the groundwater monitoring well into the greenhouse (riverside) and field cultivation areas (plain and mountain) to compare the groundwater impact of water curtain cultivation in the greenhouse complex. The characteristics of groundwater level changes classified by terrain type were analyzed using the observed data. Riverside wells have significant permeability coefficients and are close to rivers, so they are greatly affected by river flow and precipitation changes so that water level shows a specific pattern of annual changes. Most plain wells do not show a constant annual change, but observation wells near small rivers and small-scale greenhouse cultivation areas sometimes show annual and daily changes in which the water level drops during winter. Compared to other observation wells, mountain wells do not show significant yearly changes in water level and show general characteristics of bedrock aquifer well with a low permeability coefficient.

• Journal of the Korean Geographical Society
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• v.41 no.3 s.114
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• pp.283-300
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• 2006

Gaesung city of North Korea is meaningful because of the development of Gaesung industrial complex as a peace-building project and economical cooperation works between South Korea and North Korea. This article presents the characteristics of natural landscape of Gaesung through geographical names. This research was studied by literature analysis of North Korea, depth interview of North Korean labour and refugees, and second times fieldwork. The main results of this study are as follows. Firstly, the mountain landscape of Geasung revealed on geographical names characterized mountainousness and round shape. Especially, the places where are enclosed by mountain and streams are foggy and rocky. Next the landscape of stream characterizes sandy, unstable, and tidal river. Thirdly the fauna and flora which are reflected on geographical names are hawk, snake, tiger, homed owl, snapping turtle, chestnut tree, pine tree, pear tree, zelkova tree, and willow etcetera. The environmental conditions of habitation of these are similar to the natural environment of Gaesung. Besides, the geographical names related to soil distributed in northern mountain area of Geasung. The place names implicated cliff located on the riverside. In addition to this, the geographical name of 'Bul' implicated plain distributed in the riverside of 'Seoam' which a branch stream of 'Sacheo'. And the place names related rock located in place enclosed by mountain, river, and village. In cnclusion, Gaesung is more important to us as the Gaesung industrial complex and tourism development. But the fundamental research on Gaesung is a few because Gaesung belongs to North Korea. Therefore, this research will be useful for the control and management of Gaesung in the future.

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.4
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• pp.318-329
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• 2022

Plant phenology including flowering, leaf unfolding, and leaf coloring in a forest is important to understand the forest ecosystem. Temperature rise due to recent climate change, however, can lead to plant phenology change as well as snowfall in winter season. Therefore, accurate monitoring of forest environment changes such as plant phenology and snow cover is essential to understand the climate change effect on forest management. These changes can monitor using a digital camera system. This paper introduces the detection methods for plant phenology and snow cover at the mountain region using an unmanned camera system that is a way to monitor the change of forest environment. In this study, the Automatic Mountain Meteorology Stations (AMOS) operated by Korea Forest Service (KFS) were selected as the testbed sites in order to systematize the plant phenology and snow cover detection in complex mountain areas. Multi-directional Internet Protocol (IP) camera system that is a kind of unmanned camera was installed at AMOS located in Seoul, Pyeongchang, Geochang, and Uljin. To detect the forest plant phenology and snow cover, the Red-Green-Blue (RGB) analysis based on the IP camera imagery was developed. The results produced by using image analysis captured from IP camera showed good performance in comparison with in-situ data. This result indicates that the utilization technique of IP camera system can capture the forest environment effectively and can be applied to various forest fields such as secure safety, forest ecosystem and disaster management, forestry, etc.

• 한국전산유체공학회:학술대회논문집
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• 2010.05a
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• pp.493-495
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• 2010

A three-dimensional flow simulation is performed to investigate the flow field in the ski resort on complex terrain. The present paper aims to study the wind effects of mountainous terrain on the gondola safety. Strong wind happens in the ski resort on the mountain by complex terrain and it causes the dangerous accident of gondola. A digital map around the ski resort area is used to model the actual complex terrain for a 3-D analysis domain. Wind direction and speed to be used as a boundary condition are taken from local meteorological reports. The numerical results show details of the velocity distribution around a ski resort. From the results, we can suggest the modification of the installation of gondola for the safety due to strong wind.

• Wind and Structures
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• v.24 no.6
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• pp.565-578
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• 2017

The meteorological model WRF is used to investigate the wind circulation in Valle Camonica, Italy, an alpine valley that includes a large subalpine lake. The aim was to obtain the information necessary to evaluate the wind potential of this area and, from a methodological point of view, to suggest how numerical modeling can be used to locate the most interesting spots for wind exploitation. Two simulations are carried out in order to analyze typical scenarios occurring in the valley. In the first one, the diurnal cycle of thermally-induced winds generated by the heating-cooling of the mountain range encircling the valley is analyzed. The results show that the mountain slopes strongly affect the low-level winds during both daytime and nighttime, and that the correct setting of the lake temperature improves the quality of the meteorological fields provided by WRF significantly. The second simulation deals with an event of strong downslope winds caused by the passage of a cold front. Comparisons between simulated and measured wind speed, direction and air temperature are also shown.

• Journal of Forest and Environmental Science
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• v.6 no.1
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• pp.8-17
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• 1989

Recent development of industry and urbanization in the interior of mountainous area increases the possibility of occurence of natural disaster, such as flood, landslide and deblis-flow. Erosion control facilities, which were the most significant activity to riverbed fixiation, were constructed at the downstream of the experimental basin. In the mountain torrents, the complex bed load transport has occurred by the drift of running water, and resulting in a formation of terrace deposits. Especially, channel migration caused by scouring and deposition frequently occurs at the wide areas of the river bed. Consequently, the unsymmetrical river bed charactristics indicate the degree of the channel migration.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2008.04a
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• pp.222-227
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• 2008

Complex terrain like hill, mountain, and escarpment etc. makes complex air flow. This topographic condition will affect not only speed but also turbulence of wind over the complex terrain. In this paper, turbulence intensities are considered to investigate characteristics of wind over cone-type hills. There are five simple hill models with different slope 0.1${\sim}$0.5(tan${\theta}$) for wind tunnel test. It was observed through wind tunnel tests that turbulence intensities of down-slope wind at the end of the 3-Dimensional hills remarkably increased but ones of windward slope wind at the front side of the hills slightly increased. Also, turbulence intensities proportionally increased with slope of the cone-type hills.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.1
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• pp.55-63
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• 2016

Temperature lapse rate within the planetary boundary layer shows a diurnal cycle with a substantial variation. The widely-used lapse rate value for the standard atmosphere may result in unaffordable errors if used in interpolating hourly temperature in complex terrain. We propose a simple method for estimating hourly lapse rate and evaluate whether this scheme is better than the conventional method using the standard lapse rate. A standard curve for lapse rate based on the diurnal course of temperature was drawn using upper air temperature for 1000hPa and 925hPa standard pressure levels. It was modulated by the hourly sky condition (amount of clouds). In order to test the reliability of this method, hourly lapse rates for the 500-600m layer over Daegwallyeong site were estimated by this method and compared with the measured values by an ultrasonic temperature profiler. Results showed the mean error $-0.0001^{\circ}C/m$ and the root mean square error $0.0024^{\circ}C/m$ for this vertical profile experiment. An additional experiment was carried out to test if this method is applicable for the mountain slope lapse rate. Hourly lapse rates for the 313-401m slope range in a complex watershed ('Hadong Watermark 2') were estimated by this method and compared with the observations. We found this method useful in describing diurnal cycle and variation of the mountain slope lapse rate over a complex terrain despite larger error compared with the vertical profile experiment.