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The problem lies in the load lock from the wheel arm, the BLDC motor whose distance cannot be adjusted, and the flywheel whose movement is less smooth than the original design. The purpose of refining the design is to obtain smooth movement and the position of the load lock from the wheel arm, the BLDC motor that can be adjusted to be ergonomic and optimal. The method of refining the design and manufacture of the rear shock breaker spring type electric bicycle through the stages of working load analysis, the need for the distance of the load setting position and the BLDC motor, calculating the construction strength, manufacturing components, assembling components, and evaluating the results of the shock breaker manufacture. The results of refining the design and manufacture of the rear shock breaker spring type electric bicycle show that the movement of the load lock position from the wheel arm and the BLDC motor is smooth, the flywheel must be balanced, the dimensions of the shock breaker device are 120 cm long, 49.5 cm wide, 155 cm high, 120 rpm rotation speed, 2 cm shock breaker movement distance, and 1.5 cm sideways movement deviation which implies being able to provide adequate damping for electric bicycle riders well.

The unknown exact flexural strength of low carbon steel, Randu ribs wood, paving stones, and lightweight bricks is a problem faced. The purpose of this research is to obtain the flexural strength of low carbon steel, Randu ribs, paving stones, and lightweight bricks. The research method is carried out through the preparation of low carbon steel specimens 16mmx200mm, Randu ribs 40mmx60mmx250mm, paving stones 55mmx100mmx200mm, lightweight bricks 95mmx100mmx300mm, Tarno Grocky flexural testing machine settings, flexural testing support distance for low carbon steel 160mm, Randu ribs 220mm, paving stones 170mm, and lightweight bricks 260mm, flexural testing of each material, making flexural stress and deflection curves for low carbon steel, and analyzing flexural test results. The results of the study showed that the flexural strength of low carbon steel was 698 MPa at a deflection of 1.1 mm, the flexural strength of Randu rib wood in an upright position was 40.7 MPa, in a horizontal position was 55.5 MPa, in a normal position of paving stone in an upper position (normal) was 6.64 MPa, in a lower position (upside down) was 6.62 MPa, and in a lightweight brick was 1.28 MPa, which implies that the type of material, the distance between supports and the cross-section of the specimen greatly affect its flexural strength, except for ductile materials for low carbon steel which do not have flexural strength, but have yield strength at a certain deflection.

Problems in the transmission box of the Drilling Machine 438-02-814-0925 type (0.75 HP, 230/400V, 1425 rpm, produced in 1988) are the degradation of mechanical components for the pulley, V-belt, and rolling bearing. The purpose of maintenance and repair planning is to obtain maintenance costs, maintenance schedules in the period 2026, and the ratio of maintenance costs to profits. The maintenance and repair planning method includes collecting previous maintenance data; application of the inspection-replace-repair-overhaul (IRRO) method; evaluation of the working conditions of components, especially on the pulley, V-belt, spindle pulley (driven pulley), and rolling bearing; prediction of component service life; prediction of repairman costs; prediction of supporting equipment that will be used in maintenance; prediction of spare part replacement time or reinstallation of components after repair; estimation of maintenance and repair costs in 2026; and calculation of the ratio of maintenance costs to profits. The results of maintenance and repair planning obtained maintenance costs in 2026 amounting to Rp 4,627,000 with an estimated Drilling Machine rental rate of Rp 75,000/hour which has the opportunity to be rented for 400 hours/year, and a maintenance cost to profit ratio of 15.42% which implies that the Drilling Machine still has the opportunity to generate profits and is suitable for use in the coming years.

The purpose of this study was to determine the effect of pulley angle variations of 13.5ᵒ and 14ᵒ and roller weight variations of 12 g, 14 g, and 16 g on the torque of a 150 cm3 automatic motorcycle. The method with a quantitative approach the method used is the experimental method. For the sample of this research is a type of pulley and 3 types of rollers with different slopes and weights where the angle varies to test the 150 cm3 matic motorcycle torque used. From the results of this study results in a value where the Fcount value is greater than the Ftable means that the null hypothesis (H02) is rejected and the alternative hypothesis (H22) is accepted or the mass of the roller has an influence on torque, the Fcount value is greater than the Ftable means that the hypothesis (H01) is rejected and the alternative hypothesis (H11) is accepted or the mass of the roller has an influence on torque, and that the interaction between pulley angle and roller mass does not affect, and the Ftable value is lower than the Fcount value that the hypothesis (H03) is accepted and the alternative hypothesis (H33) is rejected, roller mass affects torque.

This research is a type of field research, where the author goes directly to the field in processed tempeh SMEs in Tempe Processed Village, Sampangan Village, Gajah Mungkur District, Semarang City. The study used data analysis techniques, namely qualitative methods with a descriptive approach. In analyzing the data, the researcher conducted observations, interviews, and documentation to obtain the required data. The results showed that to survive the COVID-19 pandemic, the efforts made were marketing through social media, promotion through social media and maintaining the quality of products and services from Tempe Processed SMEs.