• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.127-128
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• 2002

유기염소계 살충제들(organochlorine pesticides; OCPs)은 우리나라뿐만 아니라 세계적으로 농지(agricultural soils)에 많은 양이 사용되었다. 이들 성분들은 과거 10-30년전에 사용제한 및 금지되었지만, 여전히 대기중에서 상당한 수준의 농도들을 보이고, 지구적으로 계속 순환하고 있음이 보고되고 있다(Elizabeth et al., 1998). (중략)

• 발명특허
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• v.30 no.4 s.346
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• pp.40-43
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• 2005

광고의 집약체로 불리는 옥외광고는 이집트와 그리스에서 5 ,000년 전부터 이용되었던 것으로 지금도 도시나 교외지역에서 가장 널리 이용되는 커뮤니케이션 형식 중의 하나로 자리잡고 있다. 현재 옥외광고는 광고매체의 총광고비 중 3% 미만을 차지하고 있으며, 또한 게시판의 수가 점차 감소함에도 불구하고, 옥외광고 매체는 금액적인 면에서 꾸준히 증가하고 있는 것이 현실이다. 더욱이 자동차 판매업, 소매업 및 금융기업들 그리고 닷컴산업과 같은 새로운 광고주들의 광고 참여를 통해 옥외광고의 수요는 날이 갈수록 증가하고 있다.

• Journal of the Korean association of regional geographers
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• v.8 no.2
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• pp.216-228
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• 2002

This study analyzes the decision-making processes for university students to choose the location of their future houses in metropolitan area. Based on their intuitive judgment, the university students prefer the general criteria, transportation, facility, education and society, and economy in order. The Kendall coefficient of concordance W which determines the association among the rankings of the students' judgement on the importance of the general criteria is so low. It means that the students highly disagree their rankings of the importance of the general criteria. The rankings of the importance of the criteria like as transportation and education society are concentrated on a mean value, but those of the criteria like natural environment and economy are relatively dispersed. The students prefer the area between the center of Taegu-si center and its outskirts, the outskirts of Taegu-si, and the center of Taegu'si in order as an alternative location of their future house. From the specific criteria like the price of land and house, the student's preferences on the alternative locations of future house are varied as compared with those of the general criteria. According to a sensitivity analysis, the student's preference on the center of Taegu-si is increased, but that on the the outskirts of Taegu-si is decreased as the importance of facility and transportation factor is increased. On the contrary, the student's preference on the outskirts of Taegu-si is increased, but that on the center of Taegu-si is decreased as the importance of natural environments is increased.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.9 no.6
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• pp.824-832
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• 1998

The significant additional path loss is caused by scattering, diffraction, and attenuation of propagation. Most of the wave propagation models for rural areas mainly have considered the influence of topography but ignored the effects due to land usage. The goal of this paper is development of the field strength prediction program for Cheju which is used the contour map and the effects due to land usage. In oder to classify the propagation path and divide the environment of land, data of the terrain and the land-cover are formed into a pixel. Two-ray model is transformed into equivalent model by the predicted reflection coefficient and the slope of terrain. For non line of sight, the additional loss is determined by quantitative analysis. The result show good accord and the wave propagation model program can be applied to predicted the service region in rural area of Cheju.

• Journal of the Korean Association of Geographic Information Studies
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• v.20 no.2
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• pp.75-88
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• 2017

This study analyzed wind flows based on spatial and geomorphological characteristics of Daegu Metropolitan City. A three-stage analysis was performed, starting with a comparison of meteorological relationships between local wind direction (synoptic wind) and local wind flow. In the second stage the study area was subdivided into districts and suburban districts to analyze the relative change of local wind flow. In stage three, the formation of wind corridor for local wind flow, wind flow for the entire urban space, and spatial relationships between flows were verified comparatively using KLAM_21. Three results are notable, the first of which is a low correlation between synoptic wind of a region, and local wind, flow in terms of meteorology. Secondly, observations of local wind flow at five downtown districts and two suburban districts showed that there were diverse wind directions at each measurement point. This indicates that the spatial and geomorphological characteristics of areas neighboring the measurement points could affect the local wind flow. Thirdly, verifying the results analyzed using KLAM_21, compared to Atomatic Weather System(AWS) measurement data, confirmed the reliability of the numerical modelling analysis. It was determined that local wind flow in a city performs a spatial function and role in ameliorating the urban heat island phenomena. This indicates that, when an urban planning project is designed, the urban heat island phenomena could be ameliorated effectively and sustainably if local wind flow caused by immediate spatial and geomorphological characteristics is confirmed systematically and techniques are intentionally applied to connect the flows spatially within areas where urban heat islands occur.

• Journal of Environmental Impact Assessment
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• v.31 no.3
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• pp.161-172
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• 2022

This study attempts to understand urban evolution characteristics through suburban development cases considered as a contemporary urban issue. Methods are (1) Urban Expansion Intensity Index (UEII) for the 9 cities in the Korea (1980-2010) & 49 cities in the US, (2) Morphological Spatial Pattern Analysis(MSPA) and Entropy for the developed areas in the Chicago Metro (2019). Results are (1) a suburban development could be understood the universal characteristics, (2) the characteristics of the whole region might be appeared to be in a different direction from the characteristics of its sub-cities. Implications are (1) Suburban expansion can be understood as a functionally well served urban change phenomenon and it is important to focus on the functions of sub-level cities, (2) the urban evolutionary perspective makes a difference from the developmental growth perspective. The extensive empirical studies will be beneficial for better understating of urban evolution.

• Korean journal of applied entomology
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• v.62 no.4
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• pp.371-384
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• 2023

We investigated the occurrence of insect pests on street trees that were planted or naturally grew in a total of six urban and suburban parks (two sites in Iksan, one site in Gimje and three sites in Gwangju) in Honam region, South Korea from May to September, 2022. The six survey sites are divided into three characters, two 'nearby forest (NF)', two 'nearby river (NR)' and two 'nearby downtown (ND)' according to the created location of sites and the results on fauna of insect pests compared with street tree species for each character of survey sites. As results, we could discover 51 species of 49 genera in 27 families belonging to five insect orders from a total of 21 tree species belonging to 13 families in six survey sites. Among the insect taxa, hemipteran pests are most diverse with 22 species of 20 genera in 12 families and it is confirmed that Prunus × yedoensis Matsum. (Rosaceae) is damaged by most diverse 25 insect pests. With regard to character of survey sites, trees in 'nearby river' were affected by most diverse 34 insect pests, even though tree species were few compare to sites of 'nearby forest' and 'nearby downtown. Among the affected area of tree parts, leaf-feeding insect pests are most diverse with 22 species. From the present study, we provided a checklist of insect pests from the street trees and selected six most concerned species. Indeed, it is needed to conduct sustainable surveys and monitoring on occurrence of insect pests from street trees in urban and suburban parks because the species of planted street trees in parks can be extremely diverse with occurrence of unexpected insect pests.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2007.05a
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• pp.113-120
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• 2007

대구와 추풍령이 겨울철(2005년 12월${\sim}$2006년 2월)과 여름철(2006년 6월${\sim}$8월) 시간대별 일 최고기온, 일 최저기온, 일 평균기온과 풍속자료를 사용하였다. 추풍력은 대구에 인접해 있으면서 도시화의 영향을 상대적으로 매우 적게 받은 지역이다. 대상일은 대구와 추풍령의 겨울철과 여름철을 대상으로 일 최고기온과 다음날의 일 최저기온간의 차이가 $10^{\circ}C$이상인 날을 선정하고, 그 중에서 운량이 30%이하인 맑은 날을 선정하였다. 그리고 선정일을 대상으로 도심과 교외지역 야간(익일 18시${\sim}$다음날 06시까지)의 기온 냉각율을 조사한 결과는 다음과 같다. 기온하강은 두 지점 모두 풍속의 영향을 받음을 알 수 있었고, 또한 도시구조물이 많은 대구(도심)의 경우는 풍속이 강하더라도 건물에 의한 축열과 복사냉각의 억제에 기인하는 것으로 판단된다. 00시까지는 풍속과 냉각율이 비례하며 현열수송으로 냉각되고, 그 이후부터 일출까지는 풍속과 냉각율이 반비례하여 현열수송에 의한 가열의 경향을 확인할 수 있었다.

• Journal of Appropriate Technology
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• v.5 no.2
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• pp.62-69
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• 2019

Supplying stable electric power is one of the important objectives of the Official Development Assistance (ODA) because it is strongly related with improving living standards and income levels in the region. However, rural areas in many developing countries are not properly connected to national power grids, and even areas connected to national power grids are frequently blacked out due to limitations in power capacity. These lack of electric power is a major obstacle to improving income levels and improving living standards in those areas. The Korea-Tanzania Innovative and Energy Center (iTEC), which was established by Seoul National University in cooperation with the Nelson-Mandela Africa Institute of Science and Technology and Technology (NM-AIST) try to build a small solar power plant using a smart-off grid in rural area of Tanzania, where there is no electricity. 10 kW and 7 kW solar power plants are built in Mkalama Village in Kilimanajaro Region and Ngurdoto Village in Arusha Region to provide power to about 50 households each. In addition, smart monitoring systems were installed to collect data about status of power system and power consumption of each house. iTEC seeks for sustainable improvement the income level and quality of life of rural residents in developing countries through the construction of small solar power plants using smart-off grid, and the implementation of various connected projects.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.10
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• pp.2256-2271
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• 1997

In this paper, we analyze the multipath fading and the inter-satellite interference considering the satellite mobility in the LEO mobile satellite communication networks and evaluate the link perfodrmance for various wave propagation environments and reliabilities of communiation system. Multipath fading is estimated by analyzing the variation of fading margin for the satellite motion in rural, urban and suburban environments. The inter-satellite interferences are classified into 8 bypes with respect to interference path. The interferences evaluated in the paper are as follows:intra-LEO satellite interference, inter-LEO satellite interference, and GEO satellite to LEO satellite interference. As a conclusion, this apaper analyzes the change of elevation anagle and propagation distance with respect to time in the LEO satellite netwoek and prosents the variation of link margin continuously.