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The rolling process is a material forming method that is greatly influenced by the roll rotation speed parameter. Inappropriate rotation variations can cause various defects such as waves, tears, thickness irregularities, and ovalization. This review aims to compare the effect of variations in the roll machine rotation speed on the quality of rolling results on various types of materials, including Al6061-O aluminum plate, rubber sheets, and hollow and pipe-shaped materials. The method used is a literature study by collecting and comparing data on roll speed, defects that appear, deformation results, and process efficiency from several relevant journals. The results of the analysis show that high rotation speeds increase productivity but also increase the risk of defects because the material does not have time to adapt to deformation. Conversely, low rotation speeds produce more stable shapes and minimize defects, but are less efficient for mass production. Each material has a different optimal rotation range, including 23–36 rpm for Al6061-O plate, 45–72 rpm for rubber sheet formation, 24.4 rpm for hollow and pipe rolling, and around 21 rpm for corrugated plate. Overall, this study confirms that rotational speed control is a critical factor in achieving a balance between deformation quality and machining efficiency.

Discipline is a fundamental characteristic that supports student learning success. However, at the UPT SMPN 2 Galesong Selatan, high rates of lateness and irregular student behavior are still found, so an in-depth study of the school's role in fostering such discipline is needed. This study aims to understand school dynamics, identify supporting and inhibiting factors, and formulate effective strategies for improving disciplined behavior. Using qualitative methods and an interpretive phenomenological approach, data were obtained through interviews, 14 days of observation, and documentation review. Then, they were analyzed using the Miles, Huberman, and Saldaña model. The research findings indicate that coordination between the principal, vice principal for student affairs, guidance counselor, and student council president has a significant contribution to fostering student discipline. The micro-skills-based counseling program and the “Discipline Challenge” activity initiated by the student council have proven effective in increasing student compliance. The main obstacles that still arise include low parental involvement and increased teacher fatigue during the final lesson period. Based on these results, the study concluded that the implementation of teacher rotation on duty, the use of digital behavioral contracts, and strengthening the role of the Student Council (OSIS) are relevant and sustainable strategies in efforts to improve student discipline.

The braking system is a crucial component in a vehicle, where its performance is highly influenced by the wheel's rotational speed and the geometry of the brake pad. This study aims to analyze the impact of wheel rotational speed and variations in pad geometry on the temperature of the brake pad. The braking process generates heat due to friction, which, if not properly managed, can reduce braking performance and accelerate brake pad wear. The experiment was conducted at four levels of wheel rotational speed: 1000 RPM, 1500 RPM, 2000 RPM, and 2500 RPM. The testing system was designed using a braking system simulator equipped with a speed sensor (LM393) and a temperature sensor (K-type thermocouple), which were connected to an Arduino microcontroller and displayed in real-time through a Graphical User Interface (GUI) in MATLAB. The test results indicated that both the geometric shape of the brake pads and the wheel rotation speed significantly affected the resulting temperature. Standard brake pads produced the highest temperature at a speed of 2500 RPM, reaching 63.33°C. In contrast, brake pads with holes offered the best performance by maintaining a lower temperature of only 43.00°C. Furthermore, an increase in wheel rotation speed led to a noticeable rise in temperature; for standard pads, the temperature increased from 36.67°C at 1000 RPM to 63.33°C at 2500 RPM. This demonstrates that RPM is a major factor in heat generation due to friction. The MATLAB GUI effectively visualized the relationship between RPM and temperature, facilitating the analysis and evaluation of the data.

Management of household waste in Final Disposal Sites (TPA) faces a serious problem, where most of the waste accumulates and is difficult to decompose due to its complex nature. This condition substantially inhibits natural decomposition processes and limits the effectiveness of recycling efforts. Pre-processing operations, such as sorting and crushing, which are still dominated by manual methods, are proven to be inefficient, high-risk, and require large allocations of land resources and manpower. Therefore, automated technological innovation is needed to facilitate the efficient separation of organic components from inorganic materials (packaging). This research was conducted to determine the design and structural strength analysis of a hammer mill type depackaging machine, carried out using Solidworks software. Structural analysis simulation utilizes Finite Element Analysis (FEA) to determine the structural strength of the machine. The specifications of the hammer mill type depackaging machine include a capacity of 3000 kg/hour, a hammer mill input power of 12 KW, and a rotational speed of 2500 rpm with a torque of 34.54 Nm. Meanwhile, the screw conveyor input power is 0.75 KW and the rotational speed is 20 rpm. The FEA simulation analysis results for the hammer mill type depackaging machine showed that the maximum Von Mises stress value recorded is 3,022×10^7   N⁄m^2 , the maximum displacement value measured is very minimal, namely 2,793×10^(-1)  mm, and the Factor of Safety (FOS) obtained is 8.3. This FOS value significantly exceeds the required minimum safety limit (>3), confirming that the machine design has optimal reliability, fatigue resistance, and structural integrity for operation under intensive working conditions at the TPA. The conclusion of this study indicates that the engineering design of this hammer mill type depackaging machine is safe and meets structural technical requirements to proceed to the implementation phase, potentially becoming a sustainable technological solution in improving the efficiency of waste pre-processing.

The DC motor serves as the main drive of the vessel and is equipped with a rotary encoder that functions to regulate the movement of the sensor in measuring sediment levels. This rotary encoder is also used to monitor and represent the rotational speed of the DC motor. System testing was carried out by implementing a Fuzzy Logic Controller (FLC) algorithm to control the DC motor speed in moving the vessel, ensuring stable motion. This fuzzy logic–based approach is expected to improve accuracy and efficiency in sediment volume calculations, while also reducing potential errors that commonly occur in manual methods. Simulating motor speed control using the fuzzy logic algorithm in MATLAB, the best test results were achieved over several trials, with a rise time of 376.310 ms and an overshoot of 83.33%. Motor speed measurements using both a tachometer and Arduino produced consistent results, with an average relative error of 0.18%.

Oil palm (Elaeis guineensis) is a major tropical commodity in Southeast Asia that plays an important role in the global economy, especially as a raw material for the food, cosmetics, and bioenergy industries. West Kalimantan Province is one of the regions with the largest oil palm plantations in Indonesia, where its area increased from 1,166,282 Ha in 2020 to 1,449,274 Ha in 2022. Landak Regency contributes 119,326 Ha, but its productivity is still relatively low with a total production of 184,592 tons or around 1.54 tons/Ha. PTPN IV Ngabang in Landak Regency as one of the largest palm oil companies in the area also faces the problem of low productivity, thus hindering harvest rotation and the achievement of daily targets. This study aims to describe the productivity of oil palm harvester labor and find out what factors affect the productivity of oil palm harvester labor in PTPN IV, Ngabang District, Landak Regency. The method uses qualitative as an approach in finding answers with a sample of 78 respondents. The variables in this case study are labor productivity (Y) and independent/independent variables (X), namely age, working period, family dependents, mileage, and education. The data analysis technique used in this case study is analysis on multiple linear regression. The results of the study concluded that the productivity of oil palm harvesters in PTPN IV Ngabang averaged 1200,71 kg/day. Simultaneously, age, family dependents, working period, mileage, and education affect the productivity of oil palm harvester labor at PTPN IV Ngabang. Partially, the factor that greatly affects the productivity of the oil palm harvester workforce at PTPN IV Ngabang is the age factor of the worker and working period. Meanwhile, the factors of family dependents, distance traveled and labor education partially did not have a significant effect.

The Regional Drinking Water Company (PDAM) Tirta Perwira Purbalingga is a regional institution that provides clean water services to 62,748 customers in Purbalingga Regency. The company’s performance is strongly influenced by the quality of its human resources. This study aims to analyze the effect of training, work climate, and job rotation on employee performance. The research used a quantitative approach with descriptive methods and data processing through SPSS version 25.0. The population consisted of 164 employees, with a sample of 62 respondents determined by the Slovin formula (10%) using stratified random sampling. The results showed that training and work climate had a positive and significant effect on employee performance, while job rotation did not have a significant effect. The coefficient of determination (R²) was 96.4%, meaning that the three variables together explained 96.4% of employee performance, while the remaining 3.6% was influenced by other factors not examined in this study. These findings indicate that systematic training and a supportive work climate are the dominant factors in improving performance, whereas job rotation requires better alignment with employee competencies to be effective. In conclusion, PDAM Tirta Perwira needs to strengthen its training programs, foster a conducive work atmosphere, and carefully evaluate job rotation policies. The results of this study are expected to contribute to the development of human resource management strategies and provide reference material for future research on organizational performance.

Background: The scheduling of work of health workers, especially radiographers in type B hospitals, is a complex challenge due to the variety of radiology modalities, variations in the number of human resources, and the provisions of working hours regulations from the Ministry of Health of the Republic of Indonesia. Manual scheduling that is still in use tends to cause workload inequality, conflicts between employees, and operational inefficiencies. Objective: This study aims to design and develop an Artificial Intelligence (AI)-based radiographer shift scheduling system that is able to prepare work schedules automatically, fairly, flexibly, and integratedly, in accordance with hospital service regulations and needs. Research Method: This type of research is Research and Development (R&D). The development process is carried out through the stages of needs analysis, designing Python and Flask-based systems, simulating tests on data, and expert validation then the data collected and described from the initial mapping and also mapping potential problem-solving. Results: The system successfully manages morning, noon, night, and holiday shift schedules based on competence, fair rotation, and maximum working hours provisions. By showing a significant difference between user perceptions before and after using the system, which reflects improved efficiency, fairness, and ease of access to schedules. Respondents expressed satisfaction with the override feature and integrated notifications. Conclusion: The development of an AI-based radiographer shift scheduling system has proven to be feasible and effective in overcoming managerial problems of work scheduling in hospitals. This system is able to increase efficiency, transparency, and user satisfaction, and has the potential to be widely applied to various types of hospitals in Indonesia.

This study aims to analyze and improve the quality control of packaging printing production at PT XYZ by applying the Lean Six Sigma methodology. Lean Six Sigma combines waste reduction principles with statistical quality control to achieve operational excellence. The research identifies major production challenges, including high defect rates, overproduction, and ineffective inventory management, all of which contribute to increased costs and reduced efficiency. The DMAIC framework—Define, Measure, Analyze, Improve, and Control—was employed to systematically address these issues. During the Define and Measure phases, types of waste were identified and defect rates were calculated using Defects Per Million Opportunities (DPMO). In the Analyze phase, root causes were examined using a Fishbone (Ishikawa) diagram, highlighting factors related to manpower, materials, machines, and methods. The analysis revealed a sigma level of 3.2, indicating a moderate level of process quality and substantial room for improvement. To address the identified issues, several improvement strategies were proposed. These include implementing a Just-In-Time (JIT) system to reduce inventory waste, adopting the First-In-First-Out (FIFO) inventory method for better material rotation, and conducting targeted technical training for operators to minimize human error. In the Control phase, the study suggests process standardization, routine inspections, and continuous monitoring as key practices to ensure that improvements are sustained over time. The findings and recommendations from this study are expected to contribute to better quality control, reduced operational waste, and enhanced productivity in the packaging printing process. Ultimately, this approach aims to strengthen PT XYZ’s competitiveness in the printing industry by fostering a culture of continuous improvement and quality excellence.

This study aims to describe the early reading skills of first-grade students at Wahidiyah Elementary School in Tugu Village, Sendang District, Tulungagung Regency. This study uses a qualitative approach with a model adapted from John Creswell. The research subjects consisted of five students selected purposively. Data collection techniques were carried out through observation, interviews, and documentation. The focus of the study was directed at five indicators of early reading, namely: letter recognition, syllable recognition, combining letters into words, reading words, and reading simple sentences. The results of the study showed that the use of the reading wheel teaching media had a positive impact on improving students' early reading skills. Students appeared enthusiastic about participating in reading learning activities with the reading wheel media. The activity of spinning the wheel, arranging letters, and reading the results of the rotation became a fun learning tool and motivated them to be more active. This process helped students recognize letters and put words together gradually, although the achievement of each student's early reading skills varied. The reading wheel teaching media was proven to create an interactive and enjoyable learning atmosphere. The conclusion of this study is that the reading wheel media is effective for use in early reading learning in first-grade elementary schools. Researchers recommend that teachers develop and utilize similar innovative teaching media to support students' early literacy skills.

Community-based village development serves as a crucial strategy to reduce regional disparities and enhance village self-reliance. However, among the 36 villages in Bintan Regency, only two were categorized as Independent Villages in 2023, one of which is Toapaya Selatan Village. This study aims to examine how community participation contributes to the achievement of Independent Village status in Toapaya Selatan. The research applied a descriptive qualitative method, with data collected through observation, interviews, and documentation involving 15 informants. The findings reveal that community participation occurred actively across four key stages: decision-making, implementation, benefit-taking, and evaluation. In the decision-making process, residents were engaged through structured deliberations beginning at the neighborhood (RT) level and culminating in the village development planning meeting (Musrenbangdes). In the implementation stage, participation was reflected in both physical development projects and empowerment activities that fostered local capacity. The benefit-taking stage showed that residents equitably shared the outcomes of development through a system of regional rotation and principles of fairness. In the evaluation stage, the community was provided with both formal and informal spaces to voice aspirations and feedback, ensuring accountability and inclusiveness in governance. Despite the relatively high level of participation, several challenges persisted, including the dominance of representative systems, which limited direct involvement of broader community members, and the need for stronger capacity-building efforts. These findings suggest that while Toapaya Selatan Village has successfully demonstrated the potential of community-based participation in achieving independent status, sustaining and replicating this success in other villages requires continuous strengthening of community capacity, more inclusive participatory mechanisms, and institutional support. Strengthening these aspects will not only enhance the quality of participation but also ensure sustainable development outcomes that can be applied as a model for other villages.

Village communities generally have a cultural system deeply rooted in traditional values passed down through generations. This system encompasses various aspects of life, including agriculture, which is the primary source of livelihood. In Batukarang Village, Payung District, Karo Regency, North Sumatra, local agricultural culture is reflected in two key practices that remain preserved to this day: the aron tradition and kerja tahun (year work). These traditions not only demonstrate how the community carries out agrarian-based economic activities but also demonstrate how social, spiritual, and cultural elements are interwoven within Karo agricultural practices. Aron is a local term referring to small groups or communities that assist each other in farming activities. This system serves as a form of mutual cooperation that strengthens solidarity among residents. In practice, aron groups typically work in rotation on other group members' fields. In addition to speeding up the work process, this system also strengthens social bonds and fosters a sense of togetherness within village life.

This study aims to analyze the electrical energy consumption of a bench-type drilling machine, RYU RDB 13, by varying machining parameters in the form of spindle speed and feed rate. Electrical energy is a critical aspect of production efficiency in the manufacturing industry, particularly in machining processes that require continuous power consumption throughout the cutting operation. The material used in this study is aluminum 6061, chosen for its lightweight, corrosion resistance, and wide application in the automotive and aerospace industries. The drilling process was carried out using three spindle speed variations: 620 rpm, 920 rpm, and 1280 rpm, along with three feed rate variations: 0.04 mm/rev, 0.08 mm/rev, and 0.1 mm/rev. Current and voltage were measured using a digital wattmeter in real-time, and energy consumption was calculated in wattseconds (Ws) using power calculation formulas. The results indicate that increasing the feed rate and spindle speed leads to higher instantaneous power consumption. However, total energy consumption tends to decrease at higher speed and feed combinations due to shorter machining times. The optimal parameter combination was found at a feed rate of 0.1 mm/rev and a spindle speed of 1280 rpm, which resulted in the lowest energy consumption of 387 Ws and the fastest drilling time. This demonstrates that selecting the right machining parameters not only improves energy efficiency but also maintains or enhances productivity. The observed power consumption pattern typically shows a sharp increase at the beginning of the drilling process, a stable phase during the main cutting stage, and a rapid decrease towards the end of the cut. These findings contribute to a better understanding of the relationship between machining parameters and energy efficiency, serving as a basis for developing sustainable production strategies in the manufacturing sector that prioritize energy savings and cost reduction.

This study aims to determine the effect of job rotation, career development and motivation on employee performance at PT. Kemuning Group Medan Branch II. The population in this study are employees at PT. Kemuning Group Branch Medan II, amounting to 56 people, while the determination technique using the saturated sampling method. The data sources in this study are primary and secondary data. And the data analysis technique used is quantitative analysis and multiple linear regression. The results of the multiple linear regression analysis are: Y = 21,162 + 0,496X1 + -0,146X2 + 0,543X3+e. The results of the t-test (partial): 1) job rotation, with a tcount value of 7.148 > ttable 1.674, so that compensation (X1) has a significant effect on employee performance (Y) partially. 2) career development with tcount 1.538 < ttable 1.674, so career development (X2) does not have a significant effect on employee performance (Y) partially. 3) motivation with a value of tcount 6.213 > ttable 1.674 so that motivation (X3) has a significant effect on employee performance (Y) partially. F count = 35.706 > F table 2.78. Then the coefficient of determination (R2) is 0.673 (67.3%). So that it can be said that 67.3% of the variation of the independent variables, namely job rotation, career development and motivation in the model can explain the variables of employee performance at PT. Kemuning Group Branch Medan II while the remaining 32.7% is influenced by other variables outside the model.

Flywheel is an important element in the motor starter system due to its ability to store relase kinetic energy during the rotation process. This study aims to evaluate the effect of rotation speed variation and flywheel geometry shape on the kinetic energy produced, assuming the flywheel mass is fixed. The analysis is conducted through theoretical approach and numerical simulation using the rotational kinetic energy equation, with I as the moment of inertia that depends on the geometry shape,and as the angular velocity and shape of  the flywheel. The results show that the geometry shape greatly affects the moment of inertia, and at the same angular velocity, the flywheel with larger moment of inertia is able to store more kinetic energy. The conclusion of this study provides recommendations in the selection of the optimal flywheel design to improve the efficiency of the motor starter system.

This study aims to develop an automatic detection system to improve lift safety through early detection and rapid response to sling failure. The research method uses an experimental approach by designing a 3-story lift prototype that integrates a Raspberry Pi Pico microcontroller as the main processing unit, an HC-SR04 ultrasonic sensor to detect lift position, a limit switch to detect sling failure, and a mechanical braking system using a servo motor. The system is equipped with an I2C LCD for real-time display, Telegram notifications for remote monitoring, and a buzzer alarm as an early warning. The test results show that the ultrasonic sensor has a high accuracy of 97.58% with an average error of 2.42%. The system successfully detects sling failure and activates mechanical braking automatically, preventing the basket from falling freely and allowing it to stop on the nearest floor. All control functions such as navigation buttons, motor rotation direction, and limit switch accuracy work well. This system provides an innovative solution to improve elevator safety through the integration of automatic detection technology, real-time monitoring, and direct physical response that can be applied to the development of future elevator safety technology.

Audit quality is defined as the likelihood or probability that an auditor will detect and report any violations or misstatements in a client’s financial statements. This study aims to empirically examine the effect of time budget pressure and auditor rotation on audit quality, with firm size as a moderating variable. The research was conducted on non-bank financial companies listed on the Indonesia Stock Exchange during the 2019–2023 period. The study sample consisted of 50 companies selected using purposive sampling, and the data were analyzed using Moderated Regression Analysis (MRA). The results reveal that time budget pressure and auditor rotation do not have a significant effect on audit quality. Furthermore, firm size does not moderate the relationship between time budget pressure and audit quality, but it does moderate the relationship between auditor rotation and audit quality. These findings underscore the importance of effective time management and auditor rotation policies in maintaining audit quality, particularly for large-scale companies. This study may serve as a useful reference for various stakeholders in understanding the significance of managing time pressure and appropriately implementing auditor rotation to preserve and enhance audit quality.  

This study aims to determine the phytochemical content of Black Soldier Fly (BSF) larvae extract, also known as Hermitia illucens. The maceration method with 96% ethanol solvent was used for extraction, followed by evaporation using a rotation evaporator. Qualitative phytochemical tests were carried out to identify compounds such as alkaloids, flavonoids, saponins, terpenoids, polyphenols, steroids, and triterpenoids. The results showed that BSF maggot extract contained alkaloid and flavonoid compounds that were positively detected, while other compounds were not detected by the method used. The alkaloid and flavonoid content has antimicrobial, anti-inflammatory, and antioxidant properties. These results indicate that BSF larvae can function as a source of natural biopharmaceutical active ingredients. However, the type of solvent used and the process conditions used affect the success of the extraction.

This research was conducted at PTPN IV Regional II Adolina Palm Oil Plantation and Mill Unit with the aim of evaluating the effect of Ripple Mill machine efficiency on palm kernel impurity levels through a multiple linear regression analysis approach. Ripple Mill is a vital piece of equipment in the palm kernel cracking process, which plays a role in determining the quality of the palm kernel. This machine works by breaking the kernels to produce kernels that are separated from the shells. However, when machine efficiency decreases due to technical and operational factors, palm kernel impurity levels tend to increase, characterized by an increase in shell fragments, fibers, and other foreign materials. This condition can have an impact on decreasing product quality and increasing further processing costs. Data collection was carried out over five days of observations covering the variables of machine efficiency and kernel impurity levels obtained from production results. The study found a strong negative correlation between machine efficiency and impurity levels in palm kernels. This means that the higher the efficiency of the Ripple Mill, the lower the resulting palm kernel impurity levels. This finding also confirms that quality control in the production process is not only determined by raw material factors but also highly dependent on the performance of the processing machine. Furthermore, the research results demonstrate the importance of implementing preventive maintenance strategies, including regular inspections of the rotor bar, square bar, and drive motor, as well as regulating operating parameters such as rotational speed and machine load. Proper preventive maintenance and operational control are essential to sustain machine efficiency and product quality. Therefore, continuous improvement in technical and managerial aspects is essential to maintain palm kernel quality and support optimal palm oil mill productivity.

Maggots are larvae of the Black Soldier Fly (BSF) which have benefits as waste decomposers and have high potential as feed ingredients. This study aims to analyze the effect of power and time on maggot drying using microwaves. Using the Computational Fluids Dynamics (CFD) method on microwave heating with a power of 2000 watts and 2500 watts, and a residence time of 10 minutes, 20 minutes, and 30 minutes, then the final maggot temperature was tested. The results showed that the final temperature of the maggot tended to increase with increasing power and residence time. This happens because high microwave power provides large energy in a very short time. This energy is efficiently absorbed by maggots through the mechanism of dipole rotation and ionic conduction, causing molecules to vibrate and rub with high intensity. The final temperature of the maggot is between 110oC-125 oC with the highest temperature at a power of 2500 and a drying time of 30 minutes.