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Equatorial Plasma Bubbles (EPBs) generally form around sunset in equatorial to low‐latitude regions. However, based on observations of the rate total electron content (TEC) change index (ROTI) map over Indonesia and the ionosonde data from the Southeast Asian equatorial station during the super geomagnetic storm on 11 May 2024, we report that EPBs did not form during the post‐sunset period. Instead, EPBs were observed to form pre‐sunrise in the Indonesian region, an event that occurs rarely. These EPB structures developed and strengthened as they evolved and extended poleward. We suspect that the EPBs formed during the pre‐sunrise period were caused by the eastward disturbance dynamo electric field (DDEF), which begins around midnight and continues until sunrise. As a result, plasma bubbles started forming near sunrise and survived until the morning. Observations from three ground‐based GPS stations in Southeast Asia on May 11th, showed a significant decrease in TEC caused by EPBs pre‐sunrise. However, no GNSS scintillation was detected during this period. In contrast, strong scintillation was observed at mid‐latitudes. Before the formation of the EPB pre‐sunrise, the peak height of the ionospheric F layer experienced a significant increase, likely caused by the DDEF during the recovery phase. The rise in the F layer height could support the growth rate of Rayleigh‐Taylor instability. Therefore, DDEF becomes a major contributor to the formation of EPBs pre‐sunrise. Plain Language Summary Equatorial Plasma Bubbles (EPBs) are irregularities in the ionospheric layer in equatorial and low‐latitude regions, which can cause interference with radio signals and positioning errors. Typically, EPBs form after sunset due to eastward electric fields accelerating the Rayleigh‐Taylor instability process. However, we found something different based on our study during the geomagnetic storm on 11 May 2024. As is usually the case, we did not observe the formation of EPBs after sunset. Instead, a super EPB formed pre‐sunrise. This study analyzes how EPBs develop after sunset and around sunrise, including the changes that occur, the scintillation effects on radio signals, and the potential factors triggering their formation. The results show a significant decrease in electron content pre‐sunrise, which is linked to the formation of EPBs. However, radio signal disruptions were not detected in the equatorial region; intense disruptions were observed in mid‐latitudes. Our observations indicate that the eastward disturbance dynamo electric field caused by the geomagnetic storm may contribute to the formation of EPBs at this unusual time. Key Points The recovery phase of the May 2024 super geomagnetic storm caused a pre‐sunrise equatorial plasma bubble over Indonesia Pre‐sunrise equatorial plasma bubble did not cause GPS scintillation at the equator, but caused strong scintillation at mid‐latitudes Disturbance Dynamo Electric Field during the storm's recovery phase caused rapid F‐layer enhancement, leading to pre‐sunrise bubbles

This study aims to mitigate mass movement disasters to reduce the impact of the threat in the Wonolelo area and its surroundings, Pleret District, Bantul Regency, Yogyakarta Special Region. We carried disaster mitigation out by mapping the potential vulnerabilities of mass movements along with land use directions. The data used is in the form of parameters referring to the regulation of the Minister of Public Works Number 22/PRT/M/2007. Parameter data consists of natural factors and human factors. Natural factors such as morphology, constituent lithology, geological structure, vegetation, water conditions. Human factors such as human activity, population, and mitigation efforts. The observed data are at 25 observation points in the field. With the support of rainfall and seismicity data, we can carry an assessment of potential hazards out with a weighted value. The potential for mass movement vulnerability is in the medium and low-level mass movement-prone zones. Suggested disaster mitigation is structuring land use as horticultural agricultural land, production forest, protected forest, settlements, and food crop agriculture.

River basins provide homes and livelihoods to millions of people and play important roles in providing water for agriculture, drinking, industry and sewage as well as for hydropower energy production. The threat of climate change on water resources is serious and has to be taken into account in developing short, medium, and long-term development and management plans of river basins. The competition for water resources is projected to increase significantly, not only because of growing global population but also due to increasing demands from industry and agriculture. The impacts of climate change will put further stresses on water resources with projected changes in precipitation patterns. Potentially, more extreme rainfall events will occur, which will cause increased runoff and leave less water available to recharge the groundwater. The study assessed the overall vulnerability profile of the villages over the 2005 to 2011 period. The vulnerability assessment showed that villages classified as 'very vulnerable' are characterised by seven key areas: limited access to clean water particularly during the dry season, many households and buildings being located near the river banks, main economic activities being dependent on agriculture, limited access to electricity, lack of education, and health facilities. There were 17 very vulnerable villages in 2011 in the CRB. The current level of climate risk in these villages is still medium, but in the future the risk will increase significantly. Immediate adaptation actions (within 1 to 5 years) are recommended for 25 villages. Short term adaptation actions (within 5 to 10 years) are recommended for over 100 villages.

National Institute for Environmental Studies (NIES) and Centre for Climate Risk and Opportunity Management in Southeast Asia Pacific (CCROM-SEAP) working together to develop a beneficial monitoring system for measuring air pollutants. The monitoring system consists of system control units and instrument for measuring pollutants and located in a high-rise tower. This system can count how much anthropogenic and nature emission in this region. The primary sources of pollutants from the anthropogenic activity are traffic from vehicular transportation. This research focuses on air pollutants in the form of particulate matter (PM10 and PM2.5), Ozone (O3), methane (CH4), nitrogen oxide (NOx), sulphur dioxide (SO2), and carbon monoxide (CO). This research aims to measure the spatial coverage sensitivity of this NIES monitoring system in capturing the effect of the nearest traffic in Bogor. The method used is a sampling method using one day of data with the criteria of no rain and wind speed below two m/s to avoid washing out pollutants and turbulence from these pollutants. The data used are pollutants data on Saturday, June 6 th 2020, as sampling data and data traffic in Bogor City. The result from this research is NIES monitoring system can catch air pollutants in Bogor and can measure as far a radius of 0,01 degrees from the NIES monitoring system.

Mobile weather stations are needed because of their better coverage balance than stationary stations. Center for Climate Risk and Opportunity Management in Southeast Asia Pacific (CCROM-SEAP) of Bogor Agricultural University (Institut Pertanian Bogor or IPB University) developed a low-cost mini observation system using Espressif ESP32 DOIT Development Kit V1 module, which based on the internet of things (IoT) to monitor real-time meteorological elements (such as temperature, humidity, and pressure), CO 2 , PM 2.5 , and PM 10 concentration for Bogor (Center of Bogor City). With Firebase (database service by Google) integration, the system records data every 2 minutes and sent automatically to Firebase. We also create an unpublished android application called ServMo for exporting JSON to CSV format. The results show this system has a good performance for real-time monitoring purposes for a better balance of measurements coverage.

The research intends to create an application which is able to analyse sales data in a motorcycle company to predict the types of spare parts which should be stocked. This prediction is crucial since problems are often encountered while restocking. For instance, when there have been some imprecisions occurring in deciding regarding the types of spare parts to restock, the spare parts accumulate. It can cause inefficiency in terms of storage, the products quality deteriorates due to having been stored for too long, and sometimes the best-selling products are not available in the warehouse. This application is developed with Naïve Bayes Classifier (NBC) method which has a high accuracy in predicting future occurrences. This method works by calculating the probability value in each attribute class and determining the optimal probability value. From the test results, 4500 training data with 200 sample test data has 90% similarity with the results of the restock decision without application. For 500 test data, the similarity was 96%. It is proven that this method has a high accuracy so that it can help the decision makers solved the company problem in predicting the types of motorcycle parts to be restocked.

Center for Climate Risk and Opportunity Management of Bogor Agricultural University in collaboration with National Institute for Environmental Studies-Japan developed an on-line system to monitor real time air quality and greenhouse gases for three sites surrounding Jakarta area, i.e. Bogor (Center of Bogor city), Serpong (Jakarta suburb) and Cibeureum (mountainous area, background-like site). The system uses standards air-quality monitoring equipped with an array of gaseous and meteorological sensors. The system records data every minute and stores in local storage and sent automatically to a Dropbox every 6 hours. The data in the Dropbox is accessed using API and being processed and analysed using several modules to be converted into useful information and presented in a website. The website will display real time air quality for ozone (O3) and particulate matters (PM2.5 and PM10) and greenhouse gas data (CO2, CH4), Carbon monoxide (CO) Nitrogen Oxide (NOx), and Sulfur Dioxide (SO2), in the past 30-day including local weather data for the past 7 days. These data are then converted into an index indicating the status of the quality of the air surrounding the stations. The index is divided into five categories based on EPA air quality standard, namely good, moderate, unhealthy for sensitive group, unhealthy and very unhealthy. The system can provide the status of air quality index on a six hours basis and easy to be accessed by any stakeholder. The system allows local authorities, communities and industries to easily access and use the information for air quality management purposes and early warning.

National Institute for Environmental Studies (NIES) has been implementing a joint monitoring project of greenhouse gases (GHGs) and air pollutants in Indonesia with Bogor Agricultural University (IPB), Agency for the Assessment and Application of Technology (BPPT), and Meteorological, Climatological, and Geophysical Agency (BMKG). To estimate the amount of anthropogenic emissions from Jakarta megacity (Jabodetabek) and compare with city activities, we developed a ground-based comprehensive monitoring system of GHGs and air pollutants and installed it at Bogor (center of Bogor city) in March 2016, Serpong (Jakarta suburb) in August 2016, and Cibeureum (mountainous area, background-like site) in March 2017. The monitoring system consists of data acquisition/control units and the instruments for continuous measurements of CO2, CH4, CO, NOx, SO2, O3, aerosol concentrations (PM2.5, PM10, BC) and the chemical components, and meteorological parameters. Flask sampling of air is also done to analyze N2O, SF6, and carbon isotopes (13C, 14C) in CO2 and to validate the continuous measurement data. The result shows that CO2 mole fractions observed at three sites have clear diurnal variations representing the minimum values from 12 to 15 local time while the values at Bogor and Serpong are 6.8 and 7.1 ppm higher than Cibeureum, respectively.

As we know that the mathematical communication is an important skill. Optimalization mathematical communication research gave so many option as the effort to optimalized it, such as reading, discussing, writing. All of the option was concerned about learning model and how to learn. Based on the study of literature, at least there were four aspects that could affect the mathematical communication, those were teacher, learning, the learning materials, and the student itself. Not only that four, but also conceptual understanding could affect mathematical communication because the thing that student communicate were the concept that they had. Some of problem about conceptual understanding were found in triangle. On this research, researcher use qualitative method with observation, interview and test as instrument. There were found that learning model was not the only problem of the way to optimalized student mathematical communication because mathematical communication skill not only about how teacher taught in the classroom. That's why the way to optimalized it has to be fitted to the problem that founded.

The Malacca Strait as one of the main routes of world trade has the potential for the emergence of transnational crime. The strategic location of the Malacca Strait makes it fragile and vulnerable to piracy practices. The occurrence of this piracy has the potential to disrupt shipping lane traffic so that shipping safety is threatened and causes substantial losses for ship owners. But it is not only piracy that causes considerable losses, there is other factor that are also very influential besides piracy, namely accidents. One of the causes of accidents is the flow of ship traffic that is too crowded and is not immediately addressed. Therefore, it is necessary to increase the safety of ship traffic, one of which can be by increasing the Vessel Traffic Service (VTS). Vessel Traffic Service (VTS) serves to help provide reports on navigational and meteorological information for ships crossing a water. If the Vessel Traffic Service (VTS) is implemented and improved in the Malacca Strait, it is hoped that accidents and piracy can be minimized. This study aims to analyze the traffic congestion of ships in the Straits of Malacca and Singapore to optimize maritime security and safety and improve the Vessel Traffic System (VTS) in these straits. From the results of the analysis obtained data in the Strait of Malacca-Singapore there is an average trend of increasing the volume of ship traffic every year by 2% and has the potential to cause a lot of ship traffic. This data is very useful in order to improve the Vessel Traffic System (VTS) in the Malacca-Singapore Strait so that this traffic jam can be overcome.