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The purpose of this study is to develop an additional device for vehicles with fuel injection systems to improve fuel consumption efficiency and reduce exhaust emissions, even for older vehicles. The turbocyclone is an auxiliary component installed in the air intake duct before the throttle body to create a swirling airflow entering the combustion chamber. Testing was conducted at engine speeds ranging from 1500 rpm to 6500 rpm, with increments of 1000 rpm. This research aims to minimize fuel consumption and exhaust gas emissions. The experimental method was used, testing exhaust gas contents such as HC, CO, CO₂, and O₂ using a gas analyzer, and measuring fuel consumption based on fuel volume and time. Data processing employed a factorial DOE (Design of Experiments) to analyze results. The dependent variables were exhaust gas emissions and fuel consumption, while the independent variable was the turbocyclone blade angle variations of 20°, 40°, and 60°. The results show that the best reduction in exhaust emissions (HC, CO, CO₂, and O₂) and fuel efficiency occurred at a 40° blade angle, whereas fuel consumption increased at a 60° blade angle.

Motorcycle engine performance is highly dependent on the air intake system, which plays a crucial role in the combustion process. One common method for improving engine performance is modifying the intake system, either by installing additional devices or adjusting the quantity of incoming air. One innovation that is starting to be widely used is the Jet Ranger, an additional device on the intake duct that is claimed to be able to increase air flow into the combustion chamber. This study aims to determine the effect of the use of Jet Ranger and variations in the quantity of incoming air on the maximum power of a 150 cc motorcycle engine, as well as to analyze the interaction between the two variables. The study was conducted using an experimental method with a two-way factorial approach. The independent variables in this study consisted of two factors, namely the use of Jet Ranger (without Jet Ranger and with Jet Ranger) and variations in the quantity of incoming air divided into four levels (0.008; 0.012; 0.016; and 0.020 kg/s). Maximum power testing was conducted using a Leads dynotest, while the mass of incoming air was calculated based on air velocity measured using a digital anemometer. The test data were statistically analyzed using a two-way ANOVA to identify the effect of each factor and the interaction between them on engine power. The results of the study indicate that the use of Jet Ranger significantly increases engine power. Variations in the quantity of intake air also significantly affect the power generated. In addition, the interaction between the use of Jet Ranger and the quantity of intake air is proven to have a significant impact on increasing the maximum engine power. These results are in line with the theory of intake systems which states that increasing optimal air flow can increase the volumetric efficiency of the engine, and are supported by findings from previous studies. Therefore, these findings can be used as a reference in the development of air intake systems on motorcycles to achieve more optimal engine performance.

Pregnancy is a process in a woman's life, where major changes occur in her physical, mental and social aspects. These changes cannot be separated from the factors that influence them, namely physical factors, psychological factors and environmental, social, cultural and economic factors. One of the nutritional problems of pregnant women is chronic energy deficiency (KEK). Chronic energy deficiency (KEK) is a nutritional problem caused by a lack of food intake over a long period of time, a matter of years. Datar City Health Center is one of the agencies that provides health services for the local community and helps resolve problems with the health and nutritional development of mothers and children to prevent problems with malnutrition in pregnant women. The aim of the research is to make it easier for agencies to manage data and obtain complete information about the nutritional status of pregnant women. From 20 data, 3 groups were obtained, Cluster 1 had 4 data on the nutritional status of pregnant women, Cluster 2 had 4 data on the nutritional status of pregnant women and Cluster 3 had 12 data on the nutritional status of pregnant women. And the largest group obtained was cluster 3 with the data group on the nutritional status of pregnant women found in the gestational age group (X), namely 14-27 weeks old, with screening results (Y) namely adequate nutrition, and the causal factors (Z) that occurred were economic factors

This study aims to analyze the effect of barriers on standard intake manifolds on exhaust emissions in 125cc capacity injection motors. The applied barrier is expected to modify the intake air flow, which has an impact on the combustion process and the resulting exhaust emissions. The method used includes testing exhaust emissions with variations in the use of barriers under several engine conditions, including different engine speeds. The results show that the use of barriers can affect CO, HC, and O2 emission levels, with certain variations indicating changes in combustion efficiency. The conclusion of this research is that the selection of the right barrier diameter and intake manifold shape can contribute to the reduction of exhaust emissions of 125 cc injection motorcycles. The results of this study are expected to be a reference for the automotive industry in designing a more environmentally friendly intake manifold system.