bluuebunny/crossref_metadata_2025_split huggingface dataset:
Field analysis of switching transient process on the 35 kV side of a substation connecting to PV plant
Authors: Wang Ge , Zhou Yi , Zhu Jingfeng , Chen Shaoqing , Su Tao , Zhao Jingwei , Liang Wei 
Published: January 2021

Abstract
To reveal the real causes of two explosion faults of potential transformer (PT) on a substation connecting to PV plant, an on-line monitoring equipment with a sampling rate of 40 MS/s for the transient voltage was installed on the secondary side of the PT. By switching the 35kV bus bar onto the main transformer, the switching transient processes on the PT were obtained. The field measured transient process indicated that the switching transient voltage caused by switch operation induced the resonance between the charging circuit and the PT and the resonance may be the direct cause of the PT explosion. The effective measures to suppress resonance in this substation are proposed.
Research on master-slave filtering of Celestial Navigation System / Inertial Navigation System
Authors: Yan Fei , Zhao Wangyang , Wang Xingling , Wang Kai , Wang Yuanming 
Published: January 2021

Abstract
As the equipment with the highest attitude measurement accuracy and minimum drift, Celestial Navigation System (CNS) has widely applied and developed on various platforms, such as air-based, sea-based and land-based platforms. Aiming at the application characteristic of the CNS equipment, this article mainly analyzes the two operating modes based on gyro correction and overall estimation of INS error in the shipborne CNS/INS. Based on different selection of measurement information in CNS/INS, optimized choice is made in the integrated mode of gyro drift correction based on starlight and the integrated mode of satellite inertial navigation based on the overall estimation of inertial navigation error. This paper designs a master-slave filtering mode of CNS/INS to switch the filtering according to the observation conditions and verify through simulation analysis. This method can improve the adaptability of CNS/INS to the onboard environment; improve the positioning accuracy of about 40% compared with the single working mode during the long working of the integrated system, which can guarantee the navigation accuracy of the combined system.
Ghosts of landuse past: legacy effects of milldams for riparian nitrogen (N) processing and water quality functions
Authors: Inamdar Shreeram , Peipoch Marc , Gold Arthur J , Lewis Evan , Hripto Johanna , Sherman Melissa , Addy Kelly , Merritts Dorothy , Kan Jinjun , Groffman Peter M , Walter Robert , Trammell Tara L E 
Published: January 2021

Abstract
Milldams and their legacies have significantly influenced fluvial processes and geomorphology. However, less is known about their effects on riparian zone hydrology, biogeochemistry, and water quality. Here, we discuss the potential effects of existing and breached milldams on riparian nitrogen (N) processing through multiple competing hypotheses and observations from complementary studies. Competing hypotheses characterize riparian zone processes that remove (sink) or release (source) N. Elevated groundwater levels and reducing soil conditions upstream of milldams suggest that riparian zones above dams could be hotspots for N removal via denitrification and plant N uptake. On the other hand, dam removals and subsequent drops in stream and riparian groundwater levels result in drained, oxic soils which could increase soil nitrification and decrease riparian plant uptake due to groundwater bypassing the root zone. Whether dam removals would result in a net increase or decrease of N in riparian groundwaters is unknown and needs to be investigated. While nitrification, denitrification, and plant N uptake have typically received the most attention in riparian studies, other N cycle processes such as dissimilatory nitrate reduction to ammonium (DNRA) need to be considered. We also propose a novel concept of riparian discontinuum, which highlights the hydrologic and biogeochemical discontinuities introduced in riparian zones by anthropogenic structures such as milldams. Understanding and quantifying how milldams and similar structures influence the net source or sink behavior of riparian zones is urgently needed for guiding watershed management practices and for informed decision making with regard to dam removals.
Terrestrial Laser Scanner Self-Calibration: Quantitative Evaluation of Minimum Network Configuration
Authors: Salleh S M , Azmi M A A M , Abbas M A , Mustafar M A , Hashim N M , Sulaiman S A , Salleh C S 
Published: January 2021

Abstract
Two approaches available for performing self-calibration are: 1) point-based and 2) feature-based. The reliance on planes in the feature-based approach is a restriction to the aim of finding a suitable approach for on-site calibration. Also, the requirement for a strong network configuration in point-based self-calibration has made it difficult to implement on-site. The aim of this study was to investigate the suitability of lowering the network configuration requirements. Investigations of minimum network configurations were carried out by analysing minimum dimension of real-world plane on which targets are distributed. Through network analysis, standard deviation and plotted error ellipses will be used to determine the reliability of each configuration during minimising network experiment. The outcomes of this study will benefit to TLS practitioner to ensure that the employed instrument reliable to yield quality data.
Cross Section Intervals of Flood Intervals of Flood Inundation Mapping at Ungauged Area
Authors: Hashim Suhaila , Suhana Mokhtar Ernieza , Ikhwan Abdul Halim Ahmad , Mohd Naim Wan Mohd Wan , Aizam Adnan Nor , Pradhan Biswajeet 
Published: January 2021

Abstract
Digital Elevation Models (DEMs) are essential to present the continuous surface elevation and is used for flood mapping. The use of different cross-section intervals obtained from the various spatial resolution of DEMs will affect the flood depth and inundation area estimation. Therefore, a comparison study is carried out to investigate the effect of cross-section intervals on flood expansion and flood depth which is simulated using one dimensional (1D) HEC-RAS model at Padang Terap River, Malaysia. Two digital elevation models (DEMs) imageries, Interferometry Synthetic Aperture Radar (IFSAR) and Shuttle Radar Topography Mission (SRTM) are used in this study. The result was evaluated using likelihood measures (F-statistics, root mean square error (RMSE), and mean absolute error). The findings reveal the IFSAR DEM with cross-section interval 50 m has higher F-statistics of 70% on flood inundation estimation. By proposing the methodology, flood mapping can be provided accurately by considering the error that exist in the Geographical Information System (GIS) spatial context.
Tree inundation period determination for mangroves rehabilitation monitoring
Authors: Dali H M , Mokhtar M A M , Ghazali N , Zainal M Z , Zainuddin K 
Published: January 2021

Abstract
Mangroves services as coastal bioshield have been long acknowledged after the presence of mangroves has diminished a series of destructions from the extreme coastal force as a coastal barrier. However, to date, mangroves have been under threat mostly by anthropology activities. Mangroves deforestation happened at alarming rates and mangroves replanting, and rehabilitation effort yet to reach an acceptable success rate. To improve the success rate, mangroves inundation period monitoring using tacheometry method has been proposed. The approach used datum projected land elevation and mangroves tree height and overlay with annual tidal fluctuation from tide prediction tables. The output is a total inundation period for predetermined mangroves trees. Mangroves area geometry (MAG) was established at Kampung Sungai Melayu, Johor Bahru as a pilot area. Land elevation and mangroves tree height were measured using tacheometry method. Tidal fluctuations were generated based on the year 2020 Johor Bharu tidal prediction tables. From the overlay of these two datasets, five out of 40 mangroves tree in MAG area never been fully inundated but rather partly under the water surface during the high-water tide. A significant finding from the overlay is, two mangroves trees spending more than half of the year 2020 being submerged underwater and still survived. Despite the time consuming, tacheometry method for mangroves tree growth monitoring did provide a reliable and precise tree inundation period measurement.
Evaluation of Satellite Based Rainfall Estimation
Authors: Mohamad Z , Bakar M Z A , Norman M 
Published: January 2021

Abstract
Rainfall is one major source of water supply needed for most human activities encompassing agricultural activities to heavy industries. Therefore, a reliable and up to date approach shall always be required to accurately quantify rainfall precipitation. In Malaysia, there are three basic systems for providing rainfall measurements; which are conventional ground-based rain gauges, weather radar precipitation, and satellite-based precipitation. This study focused on data from Multi-Functional Transport Satellite (MTSAT-1R) and Terminal Doppler Weather Radar product for rainfall estimation in Malaysia. Both data were verified with the ground rain gauge data. Comparative analysis towards the data was taken based on daily and hourly approaches. Daily rainfall data were taken at Bukit Rajah, Batang Kali, Connaught Bridge, Petaling Jaya and Subang Jaya while hourly rainfall datasets were taken at Petaling Jaya and Subang Jaya. The satellite and radar data is processed using MTSAT HRIT and IRIS software respectively with the aid from Malaysian Meteorological Department (MMD). The correlation coefficient is used in this study to investigate the relationship between the satellite and radar with ground rain gauge data.
Geospatial Analysis of Coastline Erosion Along Pulau Tuba, Langkawi
Authors: Aizam Adnan Nor , Qistina binti Shahibul Fadilah Farah , Maisara Ahmad Idzdihar Raihan , Amry Mohd Fazly , Rauf Abdul Rasam Abdul , Suhana Mokhtar Ernieza 
Published: January 2021

Abstract
The erosion in Malaysia has brought attention to many authorities especially the coastline in the eastern part of Peninsular Malaysia. Although the erosion in the northern part of Peninsular Malaysia does not receive as much attention as the eastern part of Peninsular Malaysia, however, the issue should not be neglected. High spatial resolution satellite imageries were used for the extraction of coastline and classification level of erosion rate along with the Pulau Tuba. The coastline data was extracted using two different methods known as Maximum Likelihood (ML) and On-Screen Digitizing (OSD) in the determination of the best approach of coastline detection from the Sentinel-2 data of the year 2016 and 2019. Furthermore, the level of erosion is made based on the physical and economic parameters outlined by the National Coastal Erosion Study 2015 (NCES). Due to some inevitable constraints of Movement Control Order by the Malaysian government due to the COVID-19 pandemic, physical observation data of Pulau Tuba were collected via Google Maps. The information acquired includes type of coastal geomorphology, land use, development on the area, activities conducted, and adaptation of erosion if any. These data were utilized to determine the erosion rate and categories using the proposed model by NCES for five divided management units (MU) of the Pulau Tuba areas utilizing Erdas Imagine and ArcGIS software. The analysis found that the ML approach has under-detected the coastline length between 3.19% to 45.0% as compared to OSD for both years of 2016 and 2019. Rate of erosion for Pulau Tuba based on the NCES approach found that the highest erosion rate occurred at the MU1 (Pulau Dayang Bunting- Pulau Tuba causeway) with 2.91% and classified as K1 (critical erosion category) with a value of 4.39 m/yr−1 and the highest accretion rate at the MU3 with 3.06%. The critical erosion category was associated with the MU that has significant development and on-going activities that occurred in the area especially in MU 4 (Pulau Tuba) and MU 5 (Teluk Berembang). Other than that, the high number of erosions occurred in that section is due to the exposure of waves, wind, currents, and tides.
Mapping Immigrant Populations: A GIS-Based Public Perception Exploratory Analysis
Authors: Sumping A , Abdul Rasam A R , Adnan N A , Md Saad N 
Published: January 2021

Abstract
Mapping and analysis of the immigrant population are one of the GIS-based society contributions related to spatial community matters. The difficulty in getting a detailed map of the immigrant population in Malaysia is the main concern in this study. This exploratory socio-spatial study is conducted to analyse the external immigrant’s population distribution pattern in Shah Alam by using GIS and public perception approach. Selection of the study area, data collection, data processing and analysis are the main steps carried out in a GIS framework. A GIS map was derived from the questionnaires that were distributed among the 81 local citizens and immigrants. Most of the immigrant population occupied in the area of Section 7, Section 25 and Section 24 especially in the central part of the main city. The locals agreed that the majority of the immigrant influenced to a negative impact on society, but the immigrants believed that their presence led to a positive impact on the local physical development. Mapping the external immigrant will assist the authority in decision making and handling immigrant-related concerns
Initial investigation of hydraulics engineering for flood mitigation: A case study in Krueng Aceh Sub-watershed
Authors: Saputra A A , Saputro D D , Prastica R M S 
Published: January 2021

Abstract
Problem of flooding in the Krueng Aceh Sub-watershed occurs almost every year, thus, the study is conducted. This article aims at the initial study of flood mitigation investigations in the Krueng Aceh Sub-watershed, which consists of an analysis of existing channel hydraulics and an ideal design plan at the study site for hydrological analysis of the Sub-watershed. In addition to the analysis of channel hydraulics, analysis of the safety factors of existing channel cliffs and plans is also carried out. In addition to flood mitigation in the form of redesigning existing canals, this article proposes the construction of an earth-embankment dam. In the analysis of this existing channel, discharge is obtained by 1098.857 m3/s. When compared with the design flood discharge for a period of 100 years, the channel discharge capacity cannot accommodate flood discharge. With the redesign of the channel, the storage capacity can accommodate the flood discharge with a safety factor of 2.804, greater than the existing channel of 2.711. Earth-embankment dam is proposed with a safety factor of 3.497. Further studies need to be done flood routing to find out how much the contribution of the dam reservoir to the reduction of flooding in the study area.
The development of smoothed particle hydrodynamics (SPH) method for modeling the interaction movement of fluid layers in between two soil layers in flat surface condition
Authors: Saffanah H , Bahsan E , Marthanty R R D R 
Published: January 2021

Abstract
The liquefaction phenomenon most often happens in saturated, loose, and low density such as sandy soils. When the bearing capacity drops, loose sand tends to become compressed and behaves like a liquid. This behavior generates an interaction between sandy soils and clay soils which has a higher permeability and include its water content. Therefore, it required a method that can model large deformation movements, namely the free particle method, Smoothed Particle Hydrodynamics (SPH). The SPH Method is used to determine the layer of water formed during the cyclic load to approach the liquefaction phenomenon. The model use clay soils as solid and water layers as fluid with model geometry 0.1x0.1x0.05 m. Program parameters represent clay soils with stiffness coefficient, solid volume, and critical shear strength also fluid layers with damping coefficient, fluid volume, and viscosity. The calculation is done with Fortran Program and visualized in 2 Dimension and 3 Dimension with Gnuplot. Both will be evaluated from the movement of solid and fluid also numeric stability. In the final model the parameters Ks = 20000 N/m, Ks = 53.3 Ns/m, dan x particle = 50 reach numeric stability and all fluid particles can recognize the solid layer.
Analysis of potential liquefaction using cone penetration test data and grain size distribution test with case study of liquefaction in Lolu Village
Authors: Rahayu W , Yuliyanti I , Bahsan E 
Published: January 2021

Abstract
Liquefaction is a rare natural disaster and is very closely related to geotechnical engineering, where it occurred i\n the city of Palu in 2018 ago. One of the Palu liquefaction areas is Lolu Village, which experiences a sizeable lateral movement of up to 150 m. The research aims to identify the potential liquefaction in Lolu Village using the Cone Penetration Test (CPT) data and grain size distribution test. In evaluating liquefaction potential, the CPT data is processed with the Idriss-Boulanger method, referring to the value of soil safety factors based on the ratio between ground resistance to liquefaction (CRR) and earthquake (CSR). Whereas grain size distribution tests are carried out based on ASTM, referring to soil type composition’s influence on the level of liquefaction potential. The results from eight CPT in Lolu village shows that liquefaction potential occurs at a depth of 5 to 10 m with varying end resistance and friction ratio values of the soil. Likewise, grain size distribution tests indicate that soil types are dominated by sandy soils vulnerable to liquefaction.
The effect of rainfall on the slope stability with numerical simulation on Tawaeli-Toboli road, Central Sulawesi
Authors: Pontoh A N 
Published: January 2021

Abstract
Tawaeli-Toboli is an arterial road that often experiences landslides due to rainfall, which increases pore water pressure and thus, decreases the soil’s shear strength. This research analyzes the effect of rainfall on Tawaeli-Toboli road with numeric simulation to determine the characteristics such as changes in pore pressure and slope stability. Frequency analysis with HAVARA software was used to determine the maximum rainfall, while the dominant rain duration was analyzed using WindRose. Furthermore, the SoilVision software was used to fit grain size distribution, and the results are used to estimate the soil-water characteristic curve (SWCC). Analysis of pore water pressure changes was carried out using the SEEP/W program. The results were used as input data to determine the slope stability analysis using the SLOPE/W program. The frequency analysis result showed that the maximum amount of rainfall on Tawaeli-Toboli road is 205.698 mm after 11 days. During normal rainfall (20 mm/day), the Western slope remains stable with a safety factor value of 1.50. Simultaneously, in heavy rains, it decreases significantly to 1.350 after 11 days of rain. The eastern slope is quite stable because it has a safety factor value of 1.721 during heavy rain conditions.
The vehicle type effect to the mixed traffic flow performance (case of study: Soleh Iskandar road, Bogor, Indonesia)
Authors: Sudibyo Tri , Erizal  , Fauzan Muhammad 
Published: January 2021

Abstract
Many cities in developing South East Asia countries face a traffic congestion problem due to the enormous number of private vehicles operating on urban roads. Various traffic management policies are implemented to minimize any loss of congestion problems. Traffic management policies and strategies are established based on traffic analysis and calculation from field observation data which commonly use passenger car units (PCU) as the calculation approach. However, this approach becomes more challenging in an area with mixed traffic where the passenger car is not the majority of the traffic proportion, e.g. in many SEA cities. This study emphasizes the understanding of the hypothesized changes in the traffic performance on the same number of vehicles under the different proportion of motorcycles as a fundamental understanding for PCU application. To achieve the study goal, a traffic microsimulation-based analysis was conducted. The model was built based on the Soleh Iskandar road geometric and traffic data in Bogor, West Java, Indonesia. The motorcycle flows were simulated from 45% to 90% of total flow proportions that consistently affected the overall traffic performance. The consistent changes in traffic performance indicator swift in the 85% and 90% of motorcycles.
Forest fires and carbon emission release in semi-arid regions of Indonesia: the evidence from medium resolution of satellite imagery
Authors: Armanto AN , Perdinan  , Dasanto BD , Hidayati R 
Published: January 2021

Abstract
Forest fires are one of the causes of forest degradation and deforestation in Indonesia. Tropical savanna forests are one of the forest ecosystems found in the Indonesian region with a semi-arid climate type prone to drought and fire. Forest fires contribute to the release of greenhouse gas emissions into the atmosphere. The calculation method to estimate the burnt area is still an obstacle in calculating greenhouse gas emissions due to forest fires. This research aims to assess the burnt area in tropical savanna forest cover type using medium resolution satellite imagery data by utilizing the Normalized Burn Ratio index in four villages in East Sumba Regency and estimating greenhouse gas emissions these activities. The results showed that the NBR method does not produce an estimate of the burned area with a fair degree of accuracy because the characteristic of channel 7 (SWIR) is sensitive to vegetation moisture content. The savanna forest cover type is the type of land cover identified as the most dominant burned area. It produces the highest greenhouse gas emissions compared to other land cover types.
Application of SWAT in selecting soil and water conservation techniques for preparing management recommendation of Cilemer watershed, Banten, Indonesia
Authors: Rachman L M , Nursari E , Baskoro D P T 
Published: January 2021

Abstract
The quality of watershed ought to be maintained because of its function as a life buffer of living things, especially in water and other material needs provision. From the indication result, Cilemer watershed was degraded, therefore, it demanded planning efforts to restore watershed quality. This study aimed to determine watershed management directives and selecting some alternatives of soil and water conservation techniques by using Soil Water Analysis Technique (SWAT) method. Six scenarios were applied, there were: strip cropping (Scenario 1), agroforestry (Scenario 2), reservoir or small reservoir (Scenario 3), strip cropping and agroforestry combination (Scenario 4), strip cropping and reservoir combination (Scenario 5), and strip cropping, agroforestry, and reservoir combination (Scenario 6). The result showed Scenario 6 was the most effective to maintain watershed quality. Compared to the existing conditions, Scenario 6 could decrease Qmax-Qmin ratio by 34.57%, decreased the surface flow by 33.64%, so, the runoff coefficient decreased from 0.25 to 0.16. Moreover, Scenario 6 also increased the base flow by 52.16% (from 357.55 mm to 544.07 mm), water yield by 4.16% (from 904.55 mm to 943.68 mm). However, Scenario 2 was the most optimal scenario since its input was lighter and involving a smaller restored area.