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Agricultural Droughts Monitoring of Aceh Besar Regency Rice Production Center, Aceh, Indonesia – Application Vegetation Conditions Index using Sentinel-2 Image Data

Sugianto, Rusdi Muhammad, Budi Muhammad, Farhan Ahmad, Akhyar

Journal of Ecological Engineering

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2023

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Vol. 24, nr 1

159--171

EN

Monitoring the agricultural drought of paddy rice fields is a crucial aspect of preparing for proper action in maintaining food security in Indonesia. The Aceh Province is one of Indonesia’s national rice production centers, especially Aceh Besar Regency; it includes three central districts; Indrapuri, Kuta Cot Glie, and Seulimeum. Satellite-Sentinel 2A data have been tested to monitor the drought levels of around 2,803 Ha in the three districts in this study. This study aimed to determine the drought level in Indrapuri, Kuta Cot Glie, and Seulimeum districts, Aceh Besar Regency’s paddy rice fields using Sentinel-2A data imagery. The vegetation conditions index (VCI) of Sentinel-2 data was utilized to identify a vegetative drought level in the area for the 2018, 2019, 2020, 2021, and 2022 growing seasons. The vegetation inertia index is derived from the Normalized Difference Vegetation Index (NDVI). The results show that the VCI looked volatile, but the trendline increased by four percent, from 92.56 in July 2019 to 96.08 in July 2021. Most areas on the dates investigated found that the no drought category was still dominant. The designated data analyzed found that the June 2022 data tend to be distributed to the drought in extreme, severe, moderate, and mild increases compared to the previous data investigated. This figure shows an increasing drought in the study area, and the average drought index is in the category of mild drought. In addition, there has been a trendline decline in the value of NDVI in recent years, causing agricultural land for paddy rice fields to be slightly vulnerable to drought.

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Hot Tearing, Parameters, and Mould Types for Observation – Review

Akhyar

Archives of Foundry Engineering

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2022

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Vol. 22, iss. 2

25--49

EN

Hot tearing is a casting defect responsible for external and internal cracks on casting products. This irregular undesired formation is often observed during solidification and freezing. The solidification of molten metal also causes thermal contraction and shrinkage, indicating the occurrence of hot tearing when the alloy is restrained by the mould design. The parameters affecting this process include the pouring and mould temperatures, the chemical composition of the alloy, and the mould shape. Also, the factors affecting hot tearing susceptibility include pouring and mould temperatures, the grain refiner, as well as pouring speed. There are many methods of measuring the level of susceptibility to hot tearing, one of which is the thermal contraction evaluation during metal solidification, observed in cast products through several mould types. This paper discusses the hot tearing overview, the effect of pouring temperature, mould temperature, grain refiner, pouring speed on hot tearing, the type of mould, and criterion for hot tear observation.

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Oceanographic Factors as the Indicators for Shipyard Industry Development in Kutaraja Fishing Port: A Preliminary Study

Rizwan Thaib, Jalil Zulkarnain, Akhyar, Husaini

Journal of Ecological Engineering

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2021

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Vol. 22, nr 9

237--245

EN

Shipyard development in Kutaraja Fishing Port is important to improve the port performance. The studies related to shipyards are mainly focused on their productivity, facility layout, production capacity, and management and planning. Meanwhile, there are still limited studies related to the influence of oceanographic factors on shipyard development. This research aimed to identify the impact of oceanographic factors on shipyard industry development in Kutaraja fishing port. The research was conducted from December 2020 to March 2021. The data analyzed in this study were tide, wind, current, wave, bathymetry, and sediment composition. The tide, wind, current, and wave data were collected for the last three years from Meteorology, Climatology, and Geophysical Agency. The current moves from two directions, from northeast and northwest, towards the coastal areas around the eastern part of Kutaraja fishing port, closed to the breakwater. The current in the eastern part moves faster than in the western part, and the western part of the sampling area mostly has shallow waters. The highest tide occurs at 12:00 with a water height of -0.3855 meters, and the lowest tide was at 19:00 with a water height of -1.0485 meters. Fine sand dominated the sediment in the sampling area. The result indicates that oceanographic factors are essential to be incorporated as one of the indicators for shipyard development.