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Comparison of Statistical and Machine-Learning Model for Analyzing Landslide Susceptibility in Sumedang Area, Indonesia

Fitriana Hana Listi, Ismanto Rido Dwi, Tulus Jessica Stephanie, Julzarika Atriyon, Nugroho Jalu Tejo, Manalu Johanes

Geomatics and Environmental Engineering

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2024

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Vol. 18, no. 2

73--95

EN

Landslides have produced several recurrent dangers, including losses of life and property, losses of agricultural land, erosion, population relocation, and others. Landslide mitigation is critical since population and economic expansion are rapidly followed by significant infrastructure development, increasing the risk of catastrophes. At an early stage in landslide-disaster mitigation, landslide-risk mapping must give critical information to help policies limit the potential for landslide damage. This study will utilize the comparative frequency ratio (FR) and random forest (RF) techniques; they will be utilized to properly investigate the distribution of flood vulnerability in the Sumedang area. This study has identified 12 criteria for developing a landslide-susceptibility model in the research region based on the features of past disasters in the research area. The FR and RF models scored 88 and 81% of the AUC value, respectively. Based on the McNemar test, the FR and RF models featured the same performance in determining the landslide-vulnerability level performances in Sumedang. They performed well in assessing landslides in the research region; therefore, they may be used as references in landslide prevention and references in future regional development plans by the stakeholders.

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Development of Flood-Hazard-Mapping Model Using Random Forest and Frequency Ratio in Sumedang Regency, West Java, Indonesia

Ismanto Rido Dwi, Fitriana Hana Listi, Manalu Johanes, Purboyo Alvian Aji, Prasasti Indah

Geomatics and Environmental Engineering

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2023

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Vol. 17, no. 6

129--157

EN

Flooding, often triggered by heavy rainfall, is a common natural disaster in Indonesia, and is the third most common type of disaster in Sumedang Regency. Hence, flood-susceptibility mapping is essential for flood management. The primary challenge in this lies in the complex, non-linear relationships between indices and risk levels. To address this, the application of random forest (RF) and frequency ratio (FR) methods has been explored. Ten flood-conditioning factors were determined from the references: the distance from a river, elevation, geology, geomorphology, lithology, land use/land cover, rainfall, slope, soil type, and topographic wetness index (TWI). The 35 flood locations from the flood-inventory map were selected, and the remaining 18 flood locations were used for justifying the outcomes. The flooded areas from the RF model were 28.39%; the rest (71.61%) were non-flooded areas. Also, the flooded areas from the FR method were 8.02%, and the non-flooded areas were 91.98%. The AUC for both methods was a similar value – 83.0%. This result is quite accurate and can be used by policymakers to prevent and manage future flooding in the Sumedang area. These results can also be used as materials for updating existing flood-susceptibility maps.

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Flood hazard susceptibility areas mapping using Analytical Hierarchical Process (AHP), Frequency Ratio (FR) and AHP-FR ensemble based on Geographic Information Systems (GIS): a case study for Kastamonu, Türkiye

Yilmaz Osman Salih

Acta Geophysica

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2022

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Vol. 70, no 6

2747--2769

EN

Global climate change brings with it various natural disasters. In particular, natural disasters such as foods destroy nature and human resources. The food disaster in Kastamonu province, primarily striking Bozkurt district and many other districts in Türkiye on August 11, 2021, causing both life and material losses, has been one of the most devastating disasters in the Black Sea region. In this study, various geospatial and statistical methods were used to produce food hazard susceptibility maps of Kastamonu province. In order to evaluate the food risk in Kastamonu, eleven different variables, i.e. rainfall, slope, elevation, distance from stream, land-use-land cover, lithology, curvature plan, curvature profile, Topographic Wetness Index, Stream Power Index and Normalised Differences Vegetation Index were used. Flooded areas were determined by the Modified Normalised Water Index (MNDWI) on the Google Earth Engine platform using Remote Sensing techniques. Flood points determined on the calculated MNDWI image are divided into 70% training and 30% testing dataset. Geographical Information Systems-based Analytical Hierarchy Process (AHP), Frequency Ratio (FR), and ensemble AHP-FR were used in the creation of food hazard susceptibility maps. The maps were divided into five classes: very low, low, moderate, high, and very high. On the map classified using AHP-FR, areas in high and very high sensitivity classes were calculated as 128.72 km2 and 6.89 km2 , respectively. These calculated areas constitute 0.99% and 0.05% of the entire region. On the other hand, part of Kastamonu province with an area of 484.07 km2 was determined as a moderate-risk area. This area covers 3.71% of the entire province. The remaining part of the province, with an area of 8729.39 km2 and 3697.30 km2 , is classified as very low and low, respectively. These areas cover 66.91% and 28.34% of the entire province, respectively. The study’s accuracy was tested using the receiver operating characteristic curves method. Area under curve values for AHP, FR, and AHP-FR were calculated as 0.965, 0.989, and 0.992, respectively. According to these values, using the AHP-FR ensemble gave more successful results than the other two methods.

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Effect of the thickness to length ratio on the frequency ratio of nanobeams and nanoplates

Bahrami Arian, Shiri Hamidreza, Khosravi Nima

Journal of Theoretical and Applied Mechanics

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2020

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Vol. 58 nr 1

87--96

EN

This communication presents the effect of thickness on the frequency ratio of nanobeams and nanoplates using Eringen’s nonlocal theory. Although there exist numerous works regarding the effects of thickness and small scale on the frequency ratio of nanobeams and nanoplates, none has captured and reported the true effects. The main intention of this communication is to correct the misunderstanding regarding this issue. It was found that the frequency ratio is indeed dependent on the thickness to length ratio and its variation with respect to thickness to length ratio is highly dependent on the mode number, combination of boundary conditions, plate aspect ratio, and the nonlocal parameter.

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Landslide susceptibility assessment in Constantine region (NE Algeria) by means of statistical models

Manchar N., Benabbas C., Hadji R., Bouaicha F., Grecu F.

Studia Geotechnica et Mechanica

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2018

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Vol. 40, nr 3

208--219

EN

The purpose of the present study was to compare the prediction performances of three statistical methods, namely, information value (IV), weight of evidence (WoE) and frequency ratio (FR), for landslide susceptibility mapping (LSM) at the east of Constantine region. A detailed landslide inventory of the study area with a total of 81 landslide locations was compiled from aerial photographs, satellite images and field surveys. This landslide inventory was randomly split into a testing dataset (70%) for training the models, and the remaining (30%) was used for validation purpose. Nine landslide-related factors such as slope gradient, slope aspect, elevation, distance to streams, lithology, distance to lineaments, precipitation, Normalized Difference Vegetation Index (NDVI) and stream density were used in the landslide susceptibility analyses. The inventory was adopted to analyse the spatial relationship between these landslide factors and landslide occurrences. Based on IV, WoE and FR approaches, three landslide susceptibility zonation maps were categorized, namely, “very high, high, moderate, low, and very low”. The results were compared and validated by computing area under the receiver operating characteristic (ROC) curve (AUC). From the statistics, it is noted that prediction scores of the FR, IV and WoE models are relatively similar with 73.32%, 73.95% and 79.07%, respectively. However, the map, obtained using the WoE technique, was experienced to be more suitable for the study area. Based on the results, the produced LSM can serve as a reference for planning and decision-making regarding the general use of the land.

6

Large amplitude free vibration analysis of tapered Timoshenko beams using coupled displacement field method

Rajesh K., Saheb K. M.

International Journal of Applied Mechanics and Engineering

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2018

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Vol. 23, no. 3

673--688

EN

Tapered beams are more efficient compared to uniform beams as they provide a better distribution of mass and strength and also meet special functional requirements in many engineering applications. In this paper, the linear and non-linear fundamental frequency parameter values of the tapered Timoshenko beams are evaluated by using the coupled displacement field (CDF) method and closed form expressions are derived in terms of frequency ratio as a function of slenderness ratio, taper ratio and maximum amplitude ratio for hinged-hinged and clamped-clamped beam boundary conditions. The effectiveness of the CDF method is brought out through the solution of the large amplitude free vibrations, in terms of fundamental frequency of tapered Timoshenko beams with axially immovable ends. The results obtained by the present CDF method are validated with the existing literature wherever possible.

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GIS-based technic for roadside-slope stability assessment: an bivariate approach for A1 East-West highway, North Algeria

Dahoua L., Yakovitch S. V., Hadji R. H.

Mining Science

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2017

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Vol. 24

117--127

EN

This paper presents a GIS-based method for landslide susceptibility (LS) assessment using slope-movement inventory and field data. The study has been carried out along A1-Highway (A1-H) in Hanif region as this road section is threated by several types of mass wasting. This hilly zone is known by their landslides sensitive terrains in the North of Algeria. The terrain data are collected from a Géologic map, satellite imageries, digital elevation model, rainfall data, field suveys and ancillary data. In this paper Frequency Ratios (FR) based on bivariate statistical method are evaluated by comparing the observed landslides to their controlling factors. The product of the linear summation of the FR values was a landslide susceptibility index (LSI) map. It was categorized using the natural breaks classification method. The resultant LS zonation map delineates the area into five hierarchic zones. The results confirms that the angle of the slope, plays the most role in wasting especially in road sides. The LS can be used for preliminary land use planning and hazard mitigation purpose. By means of this map the current route of the A1-H can be improved to cross less susceptibles zones.