• Advances in environmental research
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• 제9권4호
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• pp.251-273
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• 2020

Soil degradation has become a major worldwide environmental problem, particularly in arid and semi-arid climate zones due to irregular rainfall and the intensity of storms that frequently generate heavy flooding. The main objective of this study is the use of geographic information system and remote sensing techniques to quantify and to map the soil losses in the Wadi Saida watershed (624 ㎢) through the revised universal soil loss equation model and a proposed model based on the surface erosive runoff. The results Analysis revealed that the Wadi Saida watershed showed moderate to moderately high soil loss, between 0 and 1000 t/㎢/year. In the northern part of the basin in the region of Sidi Boubkeur and the mountains of Daia; which are characterized by steep slopes, values can reach up to 3000 t/㎢/year. The two models in comparison showed a good correlation with R = 0.95 and RMSE = 0.43; the use of the erosive surface runoff parameter is effective to estimate the rate of soil loss in the watersheds. The problem of soil erosion requires serious interventions, particularly in basins with disturbances and aggressive climatic parameters. Good agricultural practices and forest preservation areas play an important role in soil conservation.

• 한국농공학회논문집
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• 제53권6호
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• pp.165-170
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• 2011

Recently natural disasters such as the frequency and intensity of drought have been increasing as a result of climate change. This study suggests a drought index, WADI (Water Availability Drought Index), that considers water availability using 6 components (water intake, groundwater level, agricultural reservoir water level, dam inflow, streamflow, and precipitation) using the Z score and data monitoring on a nationwide level. SPI (Standardized Precipitation Index) was applied in coastal area. For the severe droughts of 2001 spring and 2008 autumn, the index was evaluated by comparison with reported damage areas. suggested to combine The spatial concordance rate of WADI in 2001 and 2008 for estimation of the degree of drought severity was 50 % and 24 % compared to the actual recorded data respectively.

• 한국관개배수논문집
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• 제21권1호
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• pp.78-88
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• 2014

This study is to analyze the 2012 spring drought of Korea using drought index and satellite image. The severe spring drought recorded in May of 2012 showed 36.4% of normal rainfall(99.5mm). The areas of west part of Gyeonggi-do and Chungcheong-do were particularly serious. The drought indices both the SPI(Standardized Precipitation Index) and WADI(WAter supply Drought Index) represented the drought areas from the end of May and to the severe drought at the end of June. The drought by SPI completely ended at the middle of July, but the drought by WADI continued severe drought in the agricultural reservoir watersheds of whole country even to the end of the July. On the other hand, the results by spatial NDVI(Normalized Difference Vegetation Index) and EVI(Enhanced Vegetation Index) data from Terra MODIS, both indices showed relatively low values around the areas of Sinuiju, Pyongyang, and west coast of North Korea and Gyeonggi-do and Chungcheong-do of South Korea indicating drought condition. Especially, the values of NDVI and EVI at Chungcheong-do were critically low in June compared to the normal year value.

• Smart Structures and Systems
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• 제26권6호
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• pp.781-796
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• 2020

Prediction of total sediment load is essential in an extensive range of problems such as the design of the dead volume of dams, design of stable channels, sediment transport in the rivers, calculation of bridge piers degradation, prediction of sand and gravel mining effects on river-bed equilibrium, determination of the environmental impacts and dredging necessities. This paper is aimed to investigate and predict the total sediment load of the Wadi Arbaat in Eastern Sudan. The study was estimated the sediment load by separate total sediment load into bedload and Suspended Load (SL), independently. Although the sediment records are not sufficient to construct the discharge-sediment yield relationship and Sediment Rating Curve (SRC), the total sediment loads were predicted based on the discharge and Suspended Sediment Concentration (SSC). The turbidity data NTU in water quality has been used for prediction of the SSC in the estimation of suspended Sediment Yield (SY) transport of Wadi Arbaat. The sediment curves can be used for the estimation of the suspended SYs from the watershed area. The amount of information available for Khor Arbaat case study on sediment is poor data. However, the total sediment load is essential for the optimal control of the sediment transport on Khor Arbaat sediment and the protection of the dams on the upper gate area. The results show that the proposed model is found to be considered adequate to predict the total sediment load.

• 헤리티지:역사와 과학
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• 제44권1호
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• pp.106-121
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• 2011

유네스코(UNESCO: United Nations Educational, Scientific, and Cultural Organization) 세계유산 가운데 자연유산이 차지하는 비율이 전체 지정건수의 1/3에도 못 미치며 이에 대한 큰 이유는 세계적으로 가장 탁월한 가치 즉, 과학적 혹은 보존적 관점에서 보존할 필요성이 있는 빼어난 보편적 가치(OUV: Outstanding Universal Value)를 지니고 있어야만 유네스코 세계자연유산으로 인정받기 때문이다. 한편 지금까지 지정된 180건의 세계자연유산 중 9건만이 화석과 관련된 자연유산이다. 이 연구에서는 이 9건의 화석관련 세계자연유산의 특징을 분석하고, 그들이 가진 장점을 비교하여, 우리나라가 현재 추진하고 있는 한국백악기 공룡해안(KCDC: Korean Cretaceous Dinosaur Coast)의 등재 준비에 기초 자료를 제공하고자 한다. 이 연구에서는 지난 2005년에 지정된 이집트의 Wadi Al-Hitan을 직접 방문하여, 현장을 조사하고 담당직원들과의 인터뷰를 통해 얻어진 자료를 정리하였다. Wadi Al-Hitan의 성공적인 관리와 운영체계는 세 가지 요인으로 요약할 수 있다. 첫째, 연구와 모니터링을 위한 시스템 운영이고 둘째, 관련 전문가 채용과 훈련, 그리고 마지막으로 자연친화적인 보존기법 적용과 장기 발전계획에 따른 실행이다. 향후 우리나라가 추진하는 세계자연유산 후보지역들이 성공적으로 등재되고 관리되기 위해서는 우리가 가진 장점을 최대한 부각하여 신청서 제출 이전부터 세계자연보전연맹(IUCN: International Union for Conservation of Nature) 등 국제전문가들로부터 OUV를 인정받고, 연구와 관리를 담당하는 전문가를 정식직원으로 고용하여 준비과정에서 부터 참여해야 하며, 등재 이후의 관리와 운영에도 만전을 기해야 한다. 특히, 우리나라가 보유한 유일한 세계자연유산인 '제주 화산섬과 용암동굴'의 2007년 최종 등재까지의 준비과정에서도 경험했듯이 한 지역이 세계유산으로 지정되기까지는 여러분야의 전문가들의 참여와 각 부처의 적극적인 노력이 이상적으로 조화를 이뤄야 한다.

• The Plant Pathology Journal
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• 제29권4호
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• pp.410-417
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• 2013

In 2011-2012, sixty nine samples were collected from alfalfa plants showing viral infection symptoms in Riyadh region. Mechanical inoculation with sap prepared from two collected samples out of twenty five possitive for Alfalfa mosaic virus (AMV) by ELISA were produced systemic mosaic on Vigna unguiculata and Nicotiana tabacum, local lesion on Chenopodium amaranticolor and C. quinoa. Vicia faba indicator plants that induce mosaic and mottle with AMV-Sagir isolate and no infection with AMV-Wadi aldawasser isolate. Approximately 700-bp was formed by RT-PCR using AMV coat protein specific primer. Samples from infected alfalfa gave positive results, while healthy plant gave negative result using dot blot hybridization assay. The nucleotide sequences of the Saudi isolates were compared with corresponding viral nucleotide sequences reported in GenBank. The obtained results showed that the AMV from Australia, Brazil, Puglia and China had the highest similarity with AMV-Sajer isolate. While, the AMV from Spain and New Zealaland had the lowest similarity with AMV-Sajer and Wadi aldawasser isolates. The data obtained in this study has been deposited in the GenBank under the accession numbers KC434083 and KC434084 for AMV-Sajer and AMV-Wadialdawasser respectively. This is the first report regarding the gnetic make up of AMV in Saudi Arabia.

• 대한수학회논문집
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• 제32권4호
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• pp.909-914
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• 2017

The recent research investigates the generalization of Bessel function in different forms as its usefulness in various fields of applied sciences. In this paper, we introduce a new modified form of k-Bessel functions called the generalized modified k-Bessel functions and established some of its properties.

• 대한수학회논문집
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• 제36권4호
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• pp.705-714
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• 2021

The Whittaker function and its diverse extensions have been actively investigated. Here we aim to introduce an extension of the Whittaker function by using the known extended confluent hypergeometric function 𝚽_p,v and investigate some of its formulas such as integral representations, a transformation formula, Mellin transform, and a differential formula. Some special cases of our results are also considered.

• 대한수학회논문집
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• 제34권2호
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• pp.507-522
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• 2019

The main aim of this present paper is to present a new extension of the fractional derivative operator by using the extension of beta function recently defined by Shadab et al. [19]. Moreover, we establish some results related to the newly defined modified fractional derivative operator such as Mellin transform and relations to extended hypergeometric and Appell's function via generating functions.

• 대한수학회논문집
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• 제36권3호
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• pp.495-513
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• 2021

The hypergeometric series of four variables are introduced and studied by Bin-Saad and Younis recently. In this line, we derive several fractional derivative formulas, integral representations and operational formulas for new quadruple hypergeometric series.