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Global climate change demands immediate technological advancements, particularly in the transport industry that continues to use fossil fuels. One viable solution is to reduce the size of vehicle engines to make them more fuel-efficient and lower carbon emissions. The purpose of this research is to assess the effect of reducing engine size on fuel consumption and CO₂ emissions in low-cost green car hatchbacks in Indonesia. The technique employed is straightforward analytical modeling, employing Pearson correlation analysis and linear regression among three significant variables: engine capacity, fuel economy, and CO₂ emission. The data are obtained from the technical specifications of four hatchback automobile models, all of which have an engine capacity of less than 1,200 cc. Findings indicate that smaller engine capacity is accompanied by greater fuel economy and lower carbon emissions. The lowest engine size of 998 cc is used in the Toyota Agya, which demonstrates the most efficient fuel and lowest emissions. The statistical analysis shows that there is an inverse relationship between engine size and fuel efficiency, but a positive relationship between engine size and CO₂ emissions. The limitation of sample size causes reduced statistical power of the model. In conclusion, engine downsizing can prove to be a productive approach in promoting green schemes, but additional research with a larger data set and other determinants must be undertaken to establish a more advanced and precise model.

One of the key processes in the production of APAR cylinders is the welding of cylindrical plates, which is carried out using a Longitudinal Welding Cylinder machine and the CO₂ welding method. However, in practice, operators face several challenges, mainly due to the number of process steps that do not significantly contribute to the quantity or quality of the output, resulting in reduced productivity. This study aims to improve the productivity of the welding process through a series of improvements. The methods used include data analysis and root cause identification through the Overall Equipment Effectiveness (OEE) approach and Lean Six Sigma using the DMAIC stages (Define, Measure, Analyze, Improve, Control). Based on the Define stage, the initial OEE value was 67.49%, which is still far below the world-class standard of 85%. In the Measure stage, Pareto analysis revealed that the largest downtime (2,097 minutes or 40%) was caused by cycle time issues. Further analysis showed that activities such as material setup, additional plate placement, and additional plate cutting (totaling 85 seconds) could still be optimized. During the Improve stage, modifications were made, such as eliminating the additional plate cutting process and adding a stopper to ensure accurate welding alignment. These improvements successfully reduced the cycle time from 180 seconds to 120 seconds, thereby decreasing downtime and increasing the OEE value to 76.12%.

Introduction: The integration of Digital Twin (DT) technology and the Internet of Things (IoT) into Building Energy Management Systems (BEMS) offers a transformative approach to optimizing energy consumption in buildings. This study explores the development of a Digital Twin based BEMS prototype, which leverages real time data collection, predictive analytics, and machine learning to enhance energy efficiency, reduce costs, and support sustainability goals in modern buildings. The research also addresses key gaps in current energy management systems, including real time adaptive control and integration with smart grid platforms. Literature Review: Previous research highlights the limitations of traditional BEMS, which often rely on static control strategies and lack real time adaptability. Recent advancements, including predictive maintenance and machine learning integration, have improved energy optimization. However, challenges such as data interoperability, scalability, and cybersecurity remain. This review consolidates current approaches and identifies opportunities for enhancing BEMS through the integration of DT technology, IoT, and machine learning. Materials and Method: The methodology employed involves the design of a Digital Twin based BEMS prototype, incorporating IoT sensors for real time data collection on variables such as HVAC load, occupancy, and environmental factors. The system uses time series forecasting and adaptive control strategies to optimize energy consumption. A case study building is used for validation, with performance metrics such as energy savings, CO₂ footprint reduction, and peak load reduction assessed to evaluate the system's effectiveness. Results and Discussion: The results demonstrate a significant reduction in energy consumption (up to 50%) compared to traditional BEMS, along with improved forecasting accuracy and sustainability performance. The prototype achieved a high R² score in predicting energy usage, validated through real world application in the case study building. The economic feasibility analysis showed substantial cost savings and a strong return on investment, making the system a financially viable solution for energy efficient building management.

This study aims to determine the composition and structure of vegetation and estimate the potential for carbon dioxide absorption in the Tangale Nature Reserve Area, Gorontalo Regency. The method used in this study is the determination of sampling locations carried out by purposive sampling, making multilevel plots, analyzing vegetation structure, and estimating tree biomass is done non-destructively based on measuring the height and diameter of trees at breast height (DBH), while for lower plants it is done destructively and litter is taken all in the plot area to be weighed wet and dry weight and then estimating biomass, C reserves, and CO2 uptake. The results showed that the vegetation composition consisted of 18 species dominated by the Magnoliopsida class. The highest Important Value Index is found at each observation station. Calculation of biomass value, C reserves, and CO2 uptake at each observation station showed varying results because they were influenced by vegetation type, vegetation density, vegetation composition and structure, and environmental factors. The total value of CO2 uptake by vegetation in the Tangale Nature Reserve Area is 5,304.393 tons of CO2/ha. This research provides a better understanding of carbon sequestration potential in conservation areas to support environmental conservation and climate change mitigation efforts.  

This study evaluates the impact of distributed solar-battery systems on urban electricity resilience and community carbon emissions reduction. As urban areas continue to grow, the demand for electricity has placed considerable strain on traditional centralized grids, resulting in increased vulnerabilities. The integration of decentralized energy resources (DERs), particularly solar photovoltaic (PV) systems paired with battery energy storage systems (BESS), has emerged as a promising solution to enhance grid resilience, reduce carbon emissions, and support the transition to more sustainable energy systems. This research uses a simulation-based approach to model the integration of solar-battery systems into residential blocks, assessing their impact on grid reliability, downtime reduction, and the frequency of power outages. Additionally, the study estimates the reduction in carbon dioxide (CO₂) emissions achieved by shifting from fossil-fuel-based energy generation to renewable sources such as solar PV. The results demonstrate that solar-battery systems significantly improve electricity reliability by providing backup power during outages, while also reducing CO₂ emissions by decreasing reliance on conventional grids. The study also discusses the technical and financial challenges associated with the integration of these systems, such as energy storage capacity, system efficiency, and upfront installation costs. Policy recommendations emphasize the importance of government incentives, grid modernization, and long-term financial benefits to encourage the adoption of decentralized energy solutions. Finally, the study highlights areas for future research, including advanced storage technologies and the integration of electric vehicles with solar-battery systems to further enhance energy resilience and sustainability.

Oil production from a reservoir will naturally decrease or even not be able to produce at all. This condition does not necessarily indicate that the oil reserves in the reservoir have run out. If we only rely on primary production methods (primary recovery), it is likely that there is still a lot of oil left in the reservoir, so advanced production methods are needed to be able to drain the oil that is still left in the reservoir. Advanced oil recovery technology or Enhanced Oil Recovery (EOR) continues to develop to overcome the challenges in increasing oil production from reservoirs that have entered the secondary or tertiary production stage. One method that has attracted attention is Miscible Gas Flooding (MGF), which involves injecting certain gases into the reservoir. This method allows the creation of perfect mixing conditions (miscible) between the injected gas and the oil in the reservoir, thereby increasing the efficiency of oil transfer and maximizing recovery results. This technology is a solution to maximize the potential of oil wells that have experienced decreased productivity. The main principle of Miscible Gas Flooding is to reduce the interfacial tension between oil and gas, and reduce the viscosity of the oil, so that the oil can flow more easily to the production well. Commonly used gases include carbon dioxide (CO₂), nitrogen (N₂), or light hydrocarbons such as methane and ethane. With the right pressure and temperature, these gases can mix homogeneously with oil, resulting in higher displacement efficiency compared to water or immiscible gas injection methods. These advantages make MGF one of the most effective approaches to increase oil well productivity in complex reservoirs. Although promising, the implementation of Miscible Gas Flooding requires careful planning and a comprehensive evaluation of reservoir conditions. Factors such as the minimum pressure to achieve miscibility, the type of gas used, and potential disturbances such as fingering or channeling must be carefully considered. In addition, operational costs and the infrastructure required are also aspects that need to be taken into account.

The use of natural gas to replace liquefied petroleum gas (LPG) is a strategic step to reduce dependence on imported energy and support a sustainable energy transition. The purpose of this study is to analyze the possibilities, challenges, and impacts of using natural gas as a source of household energy in Indonesia. The research method used is a qualitative approach that collects primary data through questionnaires and interviews with household users and secondary data from related magazines. The results of the study indicate that Indonesia has great potential in meeting energy needs because it is rich in natural gas reserves. From an economic perspective, the use of natural gas is cheaper than liquefied gas, especially in the long term. However, the main challenges are limited distribution infrastructure, lack of public awareness of the benefits of natural gas, and the need for regulations to support the implementation of this energy transition. The results are positive impacts such as reduced CO2 emissions, increased energy efficiency and savings in foreign exchange. In summary, the use of natural gas as a substitute for LPG is feasible, but requires strategic steps such as expanding natural gas infrastructure, educating the public, and strengthening the regulatory framework. This study recommends that the government, energy companies, and the community work together to ensure an effective and sustainable energy transition.

In  recent  years,  air  quality  has  become  an  increasingly  important  issue  in  various  cities  around  the  world.  Real-time  air  quality  monitoring  is  essential  for  identifying  pollution  problems  and  taking  appropriate  actions.  This  article  discusses  the  design  of  an  Internet  of  Things  (IoT)-based  air  quality  monitoring  system  using  the  prototype  method.  The  system  is  designed  to  monitor  air  quality  parameters  such  as  PM2.5,  PM10,  CO2,  and  temperature  in  real-time  and  present  the  data  to  users  through  a  web-based  application.

The construction industry is one of the sectors that has a significant impact on environmental damage due to high energy consumption, exploitation of natural resources, and carbon emissions. In response to these challenges, this study aims to analyze the potential for implementing sustainable construction materials to support the development of green infrastructure. Using qualitative methods through literature studies, documentation, observation, and in-depth interviews, this study evaluates the advantages, challenges, and economic and environmental impacts of various innovative materials, such as foam glass, green wall systems, bamboo composites, eco-cement, and mycelium-based blocks. The results show that these materials are able to reduce carbon emissions, increase building energy efficiency, and offer long-term cost savings. Mycelium-based blocks, in particular, are recorded as the most effective material in reducing construction costs by up to 25% and CO₂ emissions by 250 kg per project. However, the implementation of sustainable materials in Indonesia still faces obstacles such as cost, material availability, and technical regulations. Therefore, synergy is needed between the government, academics, and industry in encouraging research, preparing technical standards, and public awareness campaigns to expand the adoption of environmentally friendly materials in the national construction sector.

Public Green Open Space (RTH) is an essential element in urban spatial planning to support environmental sustainability. Through the process of photosynthesis, RTH helps absorb carbon dioxide (CO₂) produced by human activities, such as transportation and industry, thus contributing to climate change mitigation. This study aims to explore the role of RTH in absorbing CO₂ and the challenges faced in its management. The study was conducted using a systematic approach through literature analysis and case studies in several cities in Indonesia and around the world. The research results indicate that vegetation type, area size, and environmental conditions are the main factors affecting the carbon absorption capacity of RTH. Large trees have a significantly higher capacity to absorb CO₂ compared to shrubs and grass, with the ability to absorb up to 250.63 tons of CO₂ per year per tree. However, challenges such as limited RTH area, urbanization pressure, and lack of public awareness remain obstacles to optimal RTH management. The recommendations of this study include increasing the area and quality of RTH through data-based strategies, community participation in management, and the development of policies that support sustainability. With proper management, RTH can function as a climate change mitigation tool while improving the quality of life for urban communities.  

The increase in population in Boyolali Regency, which reached 1,090,131 people in 2023, has a significant impact on environmental quality, especially air quality. This study aims to calculate the oxygen produced by Sonokridanggo Urban Forest, covering an area of 2,500 m², which functions as a green open space (RTH). The methods used include measuring tree trunk diameter using the diameter breast height (dbh) method and calculating biomass and stored carbon using the allometric formula. The results showed that Ketapang (Pterocarpus indicus) species had the highest carbon storage ability, which was 16,159.67 kg, and absorbed 59,252.13 kg CO₂ equivalent, making it the main contributor to oxygen production. Overall, Sonokridanggo Urban Forest produces 401,699.18 kg of oxygen per year, enough to meet the oxygen needs of 1,274 people. Among the existing tree species, Ketapang is the largest oxygen producer with a contribution of 158,005.69 kg per year. With a contribution of about 0.11% of the total oxygen demand of Boyolali residents.

Oxygen breaks down chemicals in water into simpler parts. As a result of oxygen's ability to oxidize with pollutants, such as organic components, the pollutants are not harmful. Environmental pollution, also known as pollution, is when living things, energy substances, and/or other elements enter the environment, or when the environmental order is changed by human activities or by natural processes so that the quality of the environment decreases to a certain level that causes the environment to be less or unable to function according to its function (Basic Law on Environmental Management No. 4 of 1982). Environmental pollution events are called pollution. Pollutants are substances or materials that have the ability to pollute the environment. When a substance meets the requirements to be a pollutant, it is called a pollutant. For illustration, the level of carbon dioxide in the air of 0.033% is beneficial to plants, but higher levels can cause damage. When air quality exceeds the set standard quality values, namely emission and ambient air quality, it is called "polluted air". If the air quality worsens due to activities, but is still below the quality standard, then "Air is not polluted, only a decrease in air quality". The air quality standard limits the levels of CO2 and CO gases, as well as the boezem itself, which produces an unpleasant odor in the environment. This odor comes from the boezem itself, where there is a lot of garbage, perhaps most of it from the domestic waste of the surrounding residents. The health of AAL personnel is not affected by the presence of the Morokrembangan Boezem. The results of measurements carried out on November 8, 2019 at 08:55, with the AAL position at 7 ° 3'38.40 "E 112 ° 42'51.91, showed that there were several variables that exceeded the quality standard which would certainly have a negative impact on the environment, such as the content of sulfur dioxide, carbon dioxide, nitrogen oxides, and ammonia which are still on the threshold.

Rapid urbanization in major cities has led to the decreasing availability of green spaces, exacerbating urban challenges such as the Urban Heat Island (UHI) effect, high energy consumption in buildings, and air pollution. In response, green architecture innovations like green roofs and vertical farming present opportunities for reducing carbon footprints and improving urban sustainability. This study explores the potential for life-cycle carbon footprint reduction through the integration of green roofs and vertical farming systems in high-rise buildings, focusing on energy savings, environmental impact, and air quality improvements. Using Life-Cycle Assessment (LCA) methodology, the research evaluates carbon emissions reduction, operational energy savings, and ecosystem benefits from different building scenarios. Simulation models were developed for conventional high-rise buildings and those incorporating green roofs and vertical farming. EnergyPlus, SketchUp, and SimaPro software were used for energy consumption calculations and carbon emissions modeling. The study analyzes various intervention scenarios-baseline (no vegetation), green roof only, vertical farming only, and a combined system-based on tropical climate data from cities like Jakarta, Surabaya, and Kuala Lumpur. Results reveal that the integration of both green technologies significantly reduces cooling demand, lowers CO₂ emissions, and improves urban microclimates by reducing surface temperatures and enhancing air quality. Policy recommendations and guidelines for adopting green construction practices in tropical regions are provided, alongside suggestions for future research on optimizing these technologies, conducting economic modeling, and evaluating multi-building approaches at a district scale.

Developing and developed countries rely heavily on the use of electrical energy to carry out social and economic activities. The purpose of this study is to analyze economic growth and its influencing factors in the period 2004-2023. This research uses time series data. The data method used is the VECM model. The results of this study indicate that there is a one-way causality relationship between variables. In the short term only CO2 emission variables affect economic growth, while in the long term all variables such as electricity and population can affect economic growth.

Water quality plays an important role in maintaining the balance of aquatic ecosystems, including the abundance and diversity of plankton. This study aims to analyze the effect of various water quality parameters such as temperature, dissolved oxygen (DO), carbon dioxide (CO2) levels, Biochemical Oxygen Demand (BOD), pH, brightness, and turbidity on plankton diversity in Bozem. Data were obtained from eight observation stations with water quality parameter measurements and plankton sampling. The results showed that the water quality in Bozem was not optimal, with low DO values ​​(1.79 mg/L), high water temperatures (average 31.05°C), and low brightness (0.30 m), which contributed to the decline in plankton abundance. A total of 39 plankton genera were identified, with Synedra as the most dominant genus. Poor water quality inhibits plankton growth, which can impact the balance of the food chain in these waters. This study shows the importance of better water quality management to maintain the sustainability of aquatic ecosystems in Bozem. This study also contributes to the understanding of the multifactorial interactions between water quality parameters and plankton.  

The storage space for CO2 gas cylinders is inside the ship's accommodation, so there is a risk of danger if a leak occurs because the ship's accommodation has poor air circulation. This research is devoted to removing dangerous gases from the room. This research designs and modifies a tool that can detect CO2 levels and can provide a danger signal to the surroundings. This modification uses a Raspberry Pi Pico W microcontroller. This research method uses system design, a series of tools with wiring design and uses 2 test plans, namely: testing static and dynamic testing.  Testing the precision of the sensor by reading the CO2 leak detector using a CO2 measuring instrument obtained an average error value of 3.5%. The error value is still categorized as a safe difference value and the prototype works according to the expected function. Testing the function of the tool results in values ​​for the MQ-135 buzzer and exhaust fan sensors which will turn on if the CO2 level is above 600 ppm in accordance with the safe threshold for CO2 levels in the air which has been set in the program. Telegram request bot testing can work well as expected. Testing the Telegram Receive bot can work well as expected. However, for testing Telegram bots, requests and receives are influenced by the internet network.

Cardiogenic acute pulmonary edema is a medical emergency that requires early detection and prompt management. This condition is characterized by symptoms of acute heart failure accompanied by hypoxia. This is caused by fluid accumulation in the interstitial space of the lungs, making it difficult to exchange O2 and CO2 due to increased pulmonary capillary pressure. A 72-year-old man was reported to have acute heart failure leading to acute pulmonary edema which was caused by his acute coronary syndrome. Physical examination found blood pressure 160/100, pulse 105 x/min, respiration 42 x/min, jugular venous pressure 5+5 cmH2O, thorax found ronkhi sound (+/+), and oedema extremities. Thoracic X-ray examination found bat-wing appearance, electrocardiography found pathological Q. II-III-aVF and T. Inversion V4-V6, I-aVL, troponin 1.02 ng/mL. Immediate management was given with the target of reducing morbidity and mortality.  

Urbanization has significantly impacted air quality in cities, with vehicular emissions being a major contributor to pollution. This study explores the potential benefits of electrifying urban transportation, specifically through the adoption of electric vehicles (EVs). The findings indicate that EVs substantially reduce key pollutants such as CO₂, NOx, and PM₂.₅, improving urban air quality and mitigating climate change. The analysis shows that EV adoption can lead to a 50% reduction in CO₂ emissions in high EV adoption scenarios (70% EVs). Additionally, EVs are more energy-efficient than conventional vehicles, consuming significantly less energy per kilometer. This transition not only reduces dependence on fossil fuels but also supports sustainable urban development. Furthermore, the study highlights the public health benefits of electrification, with reduced levels of harmful pollutants leading to lower incidences of respiratory and cardiovascular diseases. Public health surveys reveal strong support for EV adoption, with respondents believing it would significantly improve air quality and health outcomes. In conclusion, the electrification of urban transportation presents a multifaceted approach to environmental sustainability, energy efficiency, and public health improvement.

Motorbikes produce exhaust gases that are dangerous for humans over the long term. Motorcycle exhaust gas is produced from incomplete combustion in the combustion chamber. The aim of this research is to anticipate the effects of exhaust gas produced by varying the thermal conductivity of the spark plug electrode and adding a percentage of octane booster to the fuel. This research uses quantitative concepts with experimental methods. Process the data using Microsoft Excel. This research was carried out at idle engine speed. The results show that emissions of CO have decreased significantly. The lowest CO emissions were obtained from a silver spark plug alloy and a 6% octane booster mixture, with a value of 2.09%. HC shows that the exhaust gas emission value has decreased very significantly. The results of HC exhaust gas emissions decreased by 671.66 ppm from the highest, 1121.33 ppm with a standard spark plug alloy and 0% octane booster mixture, to 449.67 ppm with a silver spark plug alloy and 7% octane booster mixture. Meanwhile, CO₂ exhaust emissions have increased. The highest value of CO₂ exhaust emissions are 3.77% with a mixture of silver spark plugs and a mixture of 7% octane booster.

The impact of the increase in motorized vehicles is air pollution from vehicle exhausts. Exhaust gas is a polluting substance that pollutes the air where the gas is created from exhaust gas or gas from the combustion of vehicles. One alternative way to reduce the content of harmful exhaust gases such as carbon monoxide (CO), and hydrocarbons (HC) produced by motorized vehicles is by adding a catalytic converter. In this study, the catalytic converter uses Aluminum (Al), Brass (Cu-Zn), and Copper (Cu) materials. The purpose of this study is to analyze the effect of using a catalytic converter made of Aluminum (Al), Brass (Cu-Zn), and Copper (Cu) on exhaust gas. In addition, this study aims to determine the material used as a catalytic converter in order to get the lowest level of exhaust gas. Furthermore, the research data are presented in tabular form and then analyze them using one way anova and graphs. The results showed a decrease in CO by 50% at 1500 Rpm and 59.6% at 4500 Rpm, HC by 72% at 1500 Rpm and 55% at 4500 Rpm, CO2 by 3.22% at 1500 Rpm and 7.91% at 4500 Rpm, and O2 by 5.53% at 1500 Rpm and 1.66% at 3000 Rpm.