• Journal of Environmental Science International
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• v.2 no.3
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• pp.161-177
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• 1993

The Yellow Sand Events observed over the Korean peninsula during 22-24 April, 1993 were examined using the synoptic data and GMS visible image to identify the transport path of the Yellow Sand and the main factor governing the duration of the Yellow Sand phenomenon. The 850 hPa convergence chart and the 700 hPa trajectory analyses of the air mass laden with Yellow Sand particles suggested that the Yellow Sand particles observed over Korea were probably transported from the Gobi Desert and the Loess Plateau. The duration of the Yellow Sand Events was about 35-40 hours rather shorter than normal as the high pressure system centered near the Mongolia region moved rapidly toward the Yellow Sea, which drove away the Yellow Sand particles over the Korean peninsula toward the Japan Islands, furthermore the low-level stratification of the air mass over the Korean penishula showed the unstable atmospheric condition leading to atmospheric diffusion of the particles. The trajectory analyses and the GMS visible image indicated that the long-range transport of the air mass laden with the Yellow Sand particles of this case was more dependent on the 700 hPa air flow than on the 850 hPa air flow.

• Journal of Technology Innovation
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• v.13 no.2
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• pp.133-155
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• 2005

After the publication of the competitive advantage of nations by Porter in 1990, the competitiveness of regional concentrations of industries has been often explained by the cluster concept. There are many definitions of clusters, but they mainly boil down to a geographically proximate group of interconnected companies and associated institutions in a particular field, linked by commonalities and complementarities. The shipbuilding industry in Korea can for sure be regarded as a competitive industry, as the spectacular rise of its world market share from 2% in the early 1970s to the current 38% impressively testifies, but can it be considered a cluster? Based on an analytical framework consisting of a typology of clusters and a context-sensitive evolutionary approach, the paper will show that over the last thirty years Korea's shipbuilding developed from a mere number of isolated, large shipyards (cathedrals in the desert) established by large conglomerates (chaebol) in close collaboration with the central government into an innovative cluster. The cluster is on the one hand characterised by a strongly developed supply industry and specialised universities and research institutes, but on the other hand by a weak, yet increasing role for local and regional institutions The specific and context-dependent characteristics of this innovative cluster are more important explanations for its competitiveness than the financial interventions by the central government, which are repeatedly put forward by European policy-makers in their trade war with Korea.

• Korean Journal of Agricultural Science
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• v.43 no.2
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• pp.288-297
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• 2016

This study is to evaluate the 'Private antidesertification afforestation support project' in the Kubuqi Desert through a survey of local residents and interviews with relevant personnel. Based on this survey, gender, age, and occupational differences in perception of the project were analyzed. In addition, the project was evaluated based on the OECD/DAC criteria using survey results and in-depth interviews with the relevant personnel. The survey analysis results show that the participants answered most of the questions positively, claiming that they were receiving social, economic, and environmental benefits through the project. However, most of the participants answered negatively to questions regarding the understanding of the project and relevant information. Gender differences in perception of the project were not found, whereas, age and occupational differences in perception were found. Older age groups showed higher levels of perception. Participants in the agro-livestock industry and office workers showed higher levels of perception compared to middle/high school students, the unemployed and college students. Teenagers, in particular, showed the lowest level of perception of the project, and thus, promotional activities targeting teenagers should be conducted in the future. Results of this evaluation of the project based on the OECD/DAC's five criteria (relevance, effectiveness, efficiency, impact, and sustainability) showed that the project operated effectively for the most part.

• Geomechanics and Engineering
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• v.20 no.6
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• pp.497-503
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• 2020

In the Kingdom of Saudi Arabia, the shallower depth of the earth's crust is composed of loose dune or beach sand with soluble salts. The expansive behavior of salt bearing soil, fluctuation of ground water table and extreme environmental conditions offer a variety of geotechnical problems affecting safety and serviceability of the infrastructure built on it. Despite spending money, time and other resources on repair and rehabilitation, no significant attention is paid to explore the root causes of excessive differential settlement and cracking to these facilities. The scientific solution required to ensure safety and serviceability of the constructed infrastructure is to improve the strength and durability properties of the supporting ground. In this study, shredded plastic is employed as a low cost and locally available additive to improve strength characteristics of the desert sand. The study shows a remarkable increase in the shear strength and normal settlement of the soil. A seven (07) degree increase in angle of internal friction is achieved by adding 0.4 percent of the shredded plastic additive. The effect of different proportions and sizes of the plastic strips is also investigated to obtain optimum values. Such a long-lived solution will seek to reduce maintenance and repair costs of the infrastructure facilities laid on problematic soil along with reduction of environmental pollutants.

• Journal of Plant Biotechnology
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• v.7 no.3
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• pp.155-160
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• 2005

Haloxylon recurvum (Locally known as Khar) is drought and salt tolerant plant of Thar Desert. This plant is a major biomass producer and has economic and ecological importance for the region. There is need for study on biology, propagation and genetic improvement for utilization of this plant for reclamation of saline soils. We report here on in vitro propagation of Haloxylon recurvum (Moq.) using nodal explant. Secretion of phenolic compound from explants was a major constraint for establishment of culture. This was checked by thorough washing and quick transfer of explant on fresh culture medium. Juvenile nodal explant with leaves was found suitable for culture establishment. Benzy-ladenine($4.0\;{\mu}M$) incorporated in Murashige and Skoog (MS) medium with additives (50 mg/L ascorbic acid and 25 mg/L each of adenine sulphate, arginine and citric acid) induced multiple shoots from nodal explant. Addition of $1.0\;{\mu}M$ naphthalene acetic acid (NAA) in combination with $4.0\;{\mu}M$ BAP improved the growth of axillary shoots. Further shoot amplification was achieved by repeated subculture of mother explants on fresh medium. Forty percent of the micropropagated shoots rooted on half-strength MS medium with $4.0\;{\mu}M$ indolebutyric acid (IBA) and 100 mg/L activated charcoal, at $28{\pm}2^{\circ}C$ and $60\%$ RH. Sixty percent of these plantlets were hardened in green house.

• Journal of Soil and Groundwater Environment
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• v.19 no.1
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• pp.8-25
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• 2014

The aims of this study were to determine concentrations of selected metals in Asian and non-Asian dust collected in Daejeon, Korea between February 2008 and December 2008 and to estimate the pollution level. The geochemical analyses of Asian dust (AD) and Non Asian dust (NAD) show that the mean concentrations of As, Cd, Cu, Pb, Zn, Zr, Sb, Mo and S reached levels up to 16, 209, 31, 43, 81, 28, 31, 122 and 302 times higher, respectively, than those in uncontaminated Chinese desert soils. These results indicate that both AD and NAD serve as an atmospheric repository for trace and heavymetal accumulation. The the enrichment factor (EF) and pollution index (PI) show that AD and NAD were severely contaminated by S, Mo, Zr, Cd, Pb, Zn, Sb, Cu, and As. All indices for these metals showed either strong or notably high level of pollution relative to Chinese desert soil, principally due to the severe atmospheric pollution derived from anthropogenic activities in heavily industrial Chinese cities. Therefore, Mo, Cd, Zr, As, Cu, Sb, Pb, and Zn are the ones most strongly affected by anthropogenic inputs such as airborne pollutants.

• Korean Journal of Agricultural Science
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• v.46 no.3
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• pp.601-611
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• 2019

As the economy of Korea has developed, dietary patterns have also changed in many ways. Rural areas, in particular, demonstrate relatively lower food accessibility than in urban areas. The aim of this study was to examine whether or not there were differences in food accessibility between urban and rural areas using data of the Census on Basic Characteristics of Establishments, Consumer Behavior Survey for Food, of the Korean National Health and Nutrition Examination Survey. Also investigated was how such differences would affect the frequency of food purchase, dietary intake, and nutrition intake by district. The results showed that districts with the lowest 10% in food accessibility had lower frequency of food purchase than did the highest 10% districts. In terms of nutrition intake, the daily average nutrition intake was not significantly different among districts. Yet, analysis of the amount of weekly dietary intake indicated that food oasis districts had from 1.3 to 3 times greater dietary intake than did food desert districts. These findings mean that the difference in food accessibility causes unbalanced food intake. Thus, the government must take a comprehensive approach to ensure that rural residents get greater food accessibility.

• Geomechanics and Engineering
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• v.19 no.1
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• pp.71-78
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• 2019

Massive investments are going on to promote and build transportation infrastructure all across the globe with the challenges being more than budgetary. Sandy soils which are predominant in coastal and border areas in India have typical characteristics. The shear strength of such soil is very low which makes it difficult for any kind of geotechnical construction and hence soil stabilization needs to be carried out for such soil conditions. The use of geocells is one of the most economical methods of soil improvement which is used to increase strength and stiffness and reduce the liquefaction potential of the soil. The use of geocells in stabilizing desert sand and results from a series of plate load test on unreinforced soil and geocell reinforced homogenous sand beds are presented in the present study. It also compares the field results using various load class vehicles like heavy load military vehicles on geocell reinforced soils with the experimental results and comes out with the fact that the proposed technique increases the strength and stiffness of sandy soil considerably and provides a solution for preventing settlement and subsidence.

• Journal of Korean Neurosurgical Society
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• v.64 no.4
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• pp.495-504
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• 2021

Three-dimensional printing (3DP) applications possess substantial versatility within surgical applications, such as complex reconstructive surgeries and for the use of surgical resection guides. The capability of constructing an implant from a series of radiographic images to provide personalized anatomical fit is what makes 3D printed implants most appealing to surgeons. Our objective is to describe the process of integration of 3DP implants into the operating room for spinal surgery, summarize the outcomes of using 3DP implants in spinal surgery, and discuss the limitations and safety concerns during pre-operative consideration. 3DP allows for customized, light weight, and geometrically complex functional implants in spinal surgery in cases of decompression, tumor, and fusion. However, there are limitations such as the cost of the technology which is prohibitive to many hospitals. The novelty of this approach implies that the quantity of longitudinal studies is limited and our understanding of how the human body responds long term to these implants is still unclear. Although it has given surgeons the ability to improve outcomes, surgical strategies, and patient recovery, there is a need for prospective studies to follow the safety and efficacy of the usage of 3D printed implants in spine surgery.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.255-255
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• 2020

아프리카 대륙에서 존재하는 가장 큰 사하라 사막(Sahara desert)의 면적은 지난 1세기 동안 기후변화로 인하여 10% 정도 증가하였고, 미래에도 기온상승으로 인하여 증가할 것으로 판단된다. 사하라 사막 면적의 증가로 인하여 아프리카의 자연식생과 수자원뿐만 아니라 아프리카에 거주하는 사람들의 삶에 많은 영향을 미치기에 사막의 면적 또는 경계선의 위치를 예측함은 매우 중요하다. 본 연구에서는 Coupled Model Intercomparison Project Phase 5 (CMIP5)의 36개 Global Climate Models (GCMs)과 ERA-interim 재분석 자료의 1979~2000년 강수 자료들을 이용하여 사헬(Sahel) 지대 서쪽(15W~15E, 10N~20N)과 동쪽(15E~35E, 10N~20N)의 강수량과 사막경계선을 비교하였다. 또한, 각 모델의 과거 모의 성능을 평가하여 미래 기후 예측성을 판단하고자 한다. 본 연구에서는 22년 평균 강수량이 200mm 이하인 지역을 사막이라 정의하고, 모델별로 연평균 강수량과 사막경계선에 대한 root mean square error(RMSE)를 산정하여 평가하였다. 또한, 습윤 정적 에너지(Moist. Static Energy; MSE), 바람(풍속 및 풍향) 자료를 이용하여 각 모델의 사막경계선의 오차에 대한 이유를 분석하였다. 이 연구를 바탕으로 하여 사헬 지대의 강수량 및 사막면적 모의의 불확실성 요소를 이해하고, 미래 상세 지역 수문기후 변화 예측에 활용 가능한 GCMs을 선별할 수 있을 것으로 판단한다.