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Many used ABS plastic wastes have problems in their management. The aim of this research is to obtain a prediction of the fatigue life of a mixture of ABS plastic and used ABS as an injection molding product. The research method is carried out through the stages of mixing used ABS with a volume of 10%, 20%, and 30% in ABS grade A and grade B; making fatigue test specimen molds according to R. R. Moore standards, injection molding of a mixture of used ABS and ABS grade A and grade B, checking the straightness and smoothness of the specimen surface, fatigue testing with increasing serial loads, analysis and making a graph of bending stress (S) against fatigue life (N) (S-N Curve). The results of the study showed that the addition of used ABS had an effect on the fatigue life of both grade A and grade B of ABS, where the fatigue life of grade A of ABS increased with the addition of the volume percentage from 0% -30% of used ABS with the highest value at the addition of 30%, namely 43698.9 cycles, while in grade B of ABS, the fatigue life decreased with the increase in volume from 0% -30% with the highest fatigue life in grade B of ABS plastic without a mixture or 0%, namely 41377.5 cycles, the implication of which is that the addition of 0% -30% of used ABS in grade A can increase the fatigue life, but grade B of ABS actually decreases its fatigue life.

A decline in performance in automatic motorcycles that have been used for a long time is a common problem caused by wear and tear on the Continuously Variable Transmission (CVT) system. This condition results in a reduction in the clamping force of the V-belt on the pulley, causing slippage and a decrease in transmission capacity. Based on the manufacturer's specifications, the torque is 8.32 Nm at 5500 rpm, while the test results show a torque of 7.41 Nm at 6500 rpm, a decrease of 10.9%. The study aims to analyze the effect of variations in pulley angle and surface roughness on the torque value of a 108 cm³ automatic motorcycle as a method to restore transmission performance without replacing the main components. The pulley angles tested were 14°, 13.8°, and 13.5°, while the surface roughness was varied based on the turning process with cutting inserts having nose radii of 0.2 mm, 0.4 mm, and 0.8 mm. The testing was conducted using a dynamometer at an engine speed range of 6000 – 9000 rpm. The results showed that the combination of a 13.8° pulley angle with a 0.2 mm cutting insert nose radius produced a torque of 7.41 Nm at 6500 rpm, an increase of 8.2% compared to the standard 14.5° configuration, which only produced 6.85 Nm. Modifying the pulley angle and surface roughness was proven to increase the V-belt clamping force, thereby improving transmission performance.  

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.

Leaf springs are one of the suspension systems that are still widely used in various modes of transport such as cars and trucks. The spring functions to support the load and reduce vibration from operational activities. This study aims to analyse the bending strength and hardness of steel leaf springs of trucks and cars resulting from tempering heat treatment. The three point bending method was used as the flexural strength testing method and the Rockwell C Hardness method testing was used for hardness testing with leaf springs in raw, tempered 460°C, and tempered 510°C conditions. From the results of the study, the highest average bending strength value of 3733,55 MPa was obtained and an average roughness value of 31,8 HR was obtained for the 510°C tempered truck leaf springs. This also applies to the 510°C tempered car leaf springs, where the average bending strength value obtained is 3392,65 MPa and the average hardness value obtained is 29,5 HR. Thus, it is recommended that tempering heat treatment that can be applied to truck and car leaf springs be carried out at 510°C to increase the bending strength and ductility of the leaf springs.

This research is a quantitative descriptive study with an instrument in the form of a questionnaire. Data analysis was carried out in two ways, quantitative data was analyzed by non-parametric statistics and qualitative data was classified through coding. The population and sample of this study were all 12 teachers. The results showed that (1) all teachers at SDN Kepanjen 01 Kepanjen District, Malang Regency carried out WFH according to the Government Circular Letter, namely the learning planning stage: using it for making lesson plans and discussing with fellow teachers; stages of the learning process: using google forms and WA for student attendance, zoom for delivering material, WA for giving and collecting assignments, youtube and the web for learning media; and the learning evaluation stage: using google forms for PH or PTS and gadgets to correct student evaluation results. (2) The implementation of WFH at SDN Kepanjen 01 encountered various obstacles. (3) Obstacles during WFH are categorized into obstacles in gadgets, internet, material understanding, finance, communication, and level of focus. (4) The solution to the problems experienced is adjusted to the situation and condition of teachers and students' families at SDN Kepanjen 01 so that WFH and BDR can still run optimally. (5) WFH has a positive impact, namely creating a feeling of security because it avoids the spread of covid-19, has more free time, is free to determine work schedules, and automatically reduces transportation costs. While the negative impact is that teachers experience boredom, reduced interaction with colleagues, lowers the quality of performance results, and is addicted to social media. The researcher's suggestions for teachers are that teachers should (1) implement whatever policies have been set by the Principal with full responsibility and enthusiasm; (2) discuss all the obstacles that arise during WFH with the Principal and fellow teachers in order to obtain the most appropriate solution; (3) always teach students to apply health protocols at home; and (4) although WFH has a negative impact, teachers must be able to overcome it in various ways so as not to affect the quality of learning for students.

Jembrak In this era of globalization, service is the main key in building positive relationships between service providers and consumers. One of the critical aspects in providing services is attitude or Service Attitude, namely the attitude shown by individuals or organizations in providing services to the community. Service Attitude is not just about providing services, but also creating positive experiences and added value for the communities served. In this context, research and in-depth understanding of Service Attitude becomes very important. Ethics is a branch of philosophy that considers concepts such as morality, values, and human actions. This includes consideration of what is right and wrong, both in relationships between individuals and in social and professional contexts, improving Human Resources (HR) for employees at Kotta Hotel Semarang.

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.