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The increasing demand for electricity and high dependence on the utility power grid have driven the adoption of photovoltaic (PV) power generation as an environmentally friendly alternative energy source. This study aims to analyze the techno-economic feasibility of a load-sharing PV power generation system, focusing on technical analysis, operational costs, electricity bill savings, and environmental impacts. The research was conducted using quantitative methods to compare energy from photovoltaic generation and the grid, carbon emission calculations using an emission factor of 0,87 kgCO₂/kWh, and economic evaluation through parameters such as Net Present Value (NPV), Return on Investment (ROI), Cost of Energy (COE), and Payback Period (PP). The research results indicate that the photovoltaic panel generation system enables reducing utility grid energy consumption and reducing carbon emissions by 4,85 tons of CO₂ in 2024, increasing to 8,45 tons of CO₂ in 2025. The economic analysis indicates that the NPV value is not yet optimal; however, the ROI stands at 15%, the COE is Rp. 980.08/kWh, and the Payback Period is 6,56 years. The system is feasible for long-term investment. Overall, the implementation of the photovoltaic power plant demonstrates good potential in supporting carbon emission reduction, increasing the utilization of renewable energy, and reducing dependence on fossil-based energy.

Cracker pr machines are widely used in small and medium-scale food industries. However, limitations in frame design and motor speed control often result in suboptimal machine performance. This study aims to perform a redesign of the upper conveyor frame, analyze the structural strength of the frame, and evaluate the effect of using a Variable Speed Drive (VSD) inverter on improving the production capacity of a cracker printing machine.The research method includes frame redesign, load calculation, and numerical analysis using the Finite Element Method (FEM) with SolidWorks Simulation. The applied loads consist of machine component weights and operational loads. In addition, performance testing was conducted by varying the motor rotational speed controlled by the VSD inverter to determine its effect on production output.The results show that the redesigned frame has a maximum displacement of 0.18 mm, a maximum stress of 8.9 MPa, and a minimum safety factor of 31, indicating that the structure is safe and operates within the elastic region. The implementation of the VSD inverter successfully increased the machine’s production capacity from the initial condition up to 78.5 kg/h. Based on these results, it can be concluded that the frame redesign and the application of a VSD inverter are effective in improving the performance and reliability of the cracker printing machine.

This study aims to analyze the effect of homework load and extended study hours on students’ learning stress levels. The background of this research is based on increasing academic demands that may affect students’ psychological conditions. This study employs a qualitative approach with data collected through observation and interviews. The results indicate that excessive homework load and prolonged study duration significantly contribute to higher levels of learning stress. Students tend to experience physical and mental fatigue, decreased motivation, and difficulty managing time between study and rest. In addition, pressure to achieve high academic performance further exacerbates stress levels. Other factors such as lack of environmental support and less varied teaching methods also influence students’ stress. Furthermore, students often report feelings of anxiety and emotional exhaustion when academic tasks accumulate without adequate rest periods. This condition not only affects their psychological well-being but also reduces concentration and learning effectiveness in the classroom. Therefore, balanced learning load management, appropriate task distribution, and more effective and humanistic teaching strategies are needed to reduce learning stress and improve the quality of education. Schools and educators are encouraged to consider students’ cognitive capacity and mental health in designing assignments and study schedules to create a more supportive learning environment.

In the planning of removable partial dentures (RPD), design is a crucial factor that must be tailored to each patient’s clinical condition, while one of the main challenges in RPD design is anatomical variation in the oral cavity such as torus palatinus, which may affect retention, stability, and patient comfort. This report aims to discuss the design considerations of acrylic resin RPD in patients with torus palatinus, particularly in determining optimal design modifications. A 42-year-old female patient presented with complaints of difficulty chewing due to the loss of several teeth in both the maxilla and mandible. Intraoral examination revealed missing teeth 15, 11, and 25, with healthy mucosal and periodontal conditions, and a nodular torus palatinus measuring approximately 2.5 × 2 cm was identified along the midline of the palate. RPD design planning in this case requires an individualized approach, particularly in the selection of the major connector and base adaptation to avoid pressure on the torus area, and design modifications were implemented to improve load distribution and patient comfort. The use of a U-shaped major connector with relief over the torus area effectively avoids direct contact, thereby enhancing comfort, preventing mucosal irritation, and supporting masticatory function.

This study was conducted based on the crucial role of diesel generator engines as the primary source of electrical power on board ships, making their operational reliability essential. One of the factors influencing generator engine performance is lubricating oil temperature. Excessive lubricating oil temperature may reduce lubrication effectiveness, increase friction between moving components, and lower engine efficiency. Therefore, this research aimed to identify the causes of high lubricating oil temperature in diesel generator engines and determine appropriate corrective actions. The study employed a descriptive quantitative approach. Data were collected through direct observation, interviews, and documentation during sea practice aboard MV. CL FLANDERS from 4 July 2024 to 5 July 2025. The data were analyzed using simple linear regression to examine the relationship between generator load and lubricating oil temperature. The findings revealed that generator load had a significant effect on the increase in lubricating oil temperature. Under normal operating conditions, the lubricating oil temperature ranged from 60°C to 72°C, while under abnormal conditions it increased to between 68°C and 81°C. The abnormal rise in temperature was mainly caused by cooling system problems, particularly a dirty LO cooler, scale deposits on the sea water pump impeller, and blockage in the cooling capillary pipes. The regression equation under normal conditions was Y = 45 + 0.30X, whereas under abnormal conditions it was Y = 53.5 + 0.30X. Elevated lubricating oil temperature resulted in lower oil viscosity, higher fuel consumption, and reduced diesel generator engine performance. Therefore, regular maintenance of the LO cooler, sea water pump, and continuous temperature monitoring are necessary to maintain optimum engine performance.

Trucking peirformancei is onei of thei important factors in supporting thei smoothneiss of thei clinkeir loading proceiss at PT. Varia Usaha Bahari, Maspion Port, Greisik. In practicei, seiveiral obstacleis arei still eincounteireid, such as deilays in truck arrivals, leiss optimal veihiclei conditions, and opeirational coordination that has not beiein fully maximizeid. Theisei conditions may affeict thei smoothneiss of thei clinkeir loading proceiss. This study aims to deiteirminei thei condition of trucking peirformancei in thei clinkeir loading proceiss baseid on deiscriptivei analysis and to deiteirminei thei eiffeict of trucking peirformancei on thei clinkeir loading proceiss baseid on simplei lineiar reigreission analysis. This study useid a quantitativei meithod with deiscriptivei analysis and simplei lineiar reigreission. Thei data weirei obtaineid through queistionnaireis distributeid to reispondeints involveid in clinkeir loading activitieis. Thei reisults showeid that trucking peirformancei was in thei good cateigory, with aveiragei indicator scoreis ranging from 3.7 to 3.9. Thei higheist indicator was opeirational coordination and communication at 3.9, whilei thei loweist indicator was loading punctuality at 3.7. Thei reisults of thei simplei lineiar reigreission showeid thei eiquation Y = 249.374 + 34.930X, which meians that trucking peirformancei has a positivei eiffeict on thei clinkeir loading proceiss. Thei significancei valuei of 0.000 < 0.05 indicateis that thei eiffeict is significant. Theireiforei, thei beitteir thei trucking peirformancei, thei beitteir thei clinkeir loading proceiss.

Blasting is a critical method for overburden removal in open-pit coal mines, where fragmentation quality directly impacts loading efficiency and operational costs. This study aims to analyze the actual fragmentation resulting from overburden blasting at Pit 4 Middle of PT. Victor Dua Tiga Mega, Central Kalimantan, to predict fragmentation using the Kuz-Ram model, and to evaluate the conformity of both results against the company standard (boulder size ≤144.6 cm or ≥50 cm for analysis). The research employed a quantitative comparative method. Primary data included blasting geometry and photographs of muck piles from 10 blasting events, which were analyzed using WipFrag software to obtain actual fragmentation distribution. Secondary data comprised rock characteristics and explosive properties for Kuz-Ram prediction input. The results showed significant variation in actual boulder percentage (≥50 cm), ranging from 6.19% to 32.91% with an average of 16.05% (medium category). Statistical analysis revealed a very weak negative correlation (r = -0.21) between powder factor (PF) and boulder percentage, indicating that PF is not the dominant factor within the consistent application range (0.21-0.23 kg/bcm). Comparison with Kuz-Ram predictions showed that the model consistently over-predicted coarse material, with an average difference of +25.21%, suggesting the need for rock factor (A) recalibration. It is concluded that the blasting results are inconsistent, strongly influenced by uncontrollable factors such as geological conditions. Recommendations include geometri evaluation, particularly burden and spacing, and calibration of the Kuz-Ram model for more accurate future predictions.

This study was conducted at PT. Asmin Bara Bronang, Sepan Uring Village, Kapuas Tengah District, Kapuas Regency, Central Kalimantan Province, with the aim of analyzing the productivity and influencing factors of the PC 300 excavator in coal getting activities to support the achievement of production targets. The objective of this research is to analyze the actual productivity and the factors affecting it in Sector 7 coal getting operations. The research method used field observation with a quantitative descriptive analysis approach. The results show that the productivity of the PC 300 excavator ranges from 127.12 to 224.29 tons/hour, with an average of 173.98 tons/hour. In several conditions, the productivity is still below the company’s target of 180 tons/hour. The analysis indicates that productivity is influenced by material conditions, particularly the Hardgrove Grindability Index (HGI) value of 47, which reflects relatively harder material with coarser particle size, and a moisture content of 22.71%, causing the material to be sticky and cohesive, thereby affecting the bucket filling process. In addition, operational factors such as bottom loading patterns, limited number of tailgate dump trucks, and suboptimal selection of dump truck types also contribute to productivity performance.  Based on the findings, it can be concluded that the productivity of the PC 300 excavator has not consistently met the company’s target. Therefore, improvement efforts are required, including the implementation of top loading methods, increasing the number of tailgate dump trucks, optimizing the selection of hauling equipment, and controlling material conditions that affect the digging process.    

The shaft is a crucial component in mechanical systems because it serves to transfer power and rotational motion throughout the machine. This research aims to assess the structural strength and operational performance of shafts used in a tire shredding machine through numerical simulation methods in order to achieve a safe and efficient design. The study involved several stages, including the development of shaft geometry models, the determination of boundary conditions, load application, mesh generation, and stress analysis using the finite element method. Two shaft configurations were examined: a 59 mm diameter shaft made from AISI 1045 steel and a 49 mm diameter shaft manufactured from ASTM A36 steel. The simulation results indicate that the 59 mm shaft experiences a Von Mises stress of 8.9 × 10⁻⁵ MPa, with a maximum displacement of 0 mm and a safety factor of 15. Similarly, the 49 mm shaft shows a Von Mises stress of 8.4 × 10⁻⁵ MPa, no measurable displacement, and a safety factor of 15. These findings confirm that both shaft designs are capable of safely withstanding the applied working loads. In addition, cutting system tests revealed that a 24-tooth blade achieved an efficiency of 26.9%, while a 40-tooth blade reached only 22.3%, indicating that the 24-tooth configuration provides better performance.

The Foot-and-Mouth Disease (FMD) outbreak has inflicted severe multidimensional disruptions on dairy farming communities, yet limited research has systematically examined how social, economic, and psychological impacts collectively shape farmer welfare in post-outbreak contexts, particularly in developing countries. This study aims to investigate the simultaneous effects of social, economic, and psychological impacts on the welfare of dairy farmers following the FMD outbreak in Indonesia, and to extend theoretical frameworks of welfare and resilience to the context of livestock disease crises. A quantitative survey was conducted with 150 dairy farmers in Pujon District, Malang Regency—one of the areas most severely affected by the 2022 FMD outbreak. Data were collected using structured questionnaires and analyzed using Partial Least Squares Structural Equation Modeling (PLS-SEM) with SmartPLS 4. The measurement model results was assessed for reliability and validity, while the structural model tested the hypothesized relationships. All three impact dimensions demonstrated significant positive effects on farmer welfare: social impact (β = 0.640, t = 4.431, p < 0.001), economic impact (β = 0.635, t = 4.487, p < 0.001), and psychological impact (β = 0.647, t = 4.143, p < 0.001). The model explained 95.5% of the variance in farmer welfare (R² adjusted = 0.955), indicating exceptional explanatory power. Factor loadings revealed that mutual assistance (0.990), loss of assets (0.986), and business insecurity (0.981) were the strongest indicators of social, economic, and psychological impacts, respectively. Farmer welfare in post-FMD contexts emerges from the synergistic interplay of social solidarity, economic pragmatism, and psychological resilience. The findings extend welfare utility and post-traumatic growth theories to livestock disease settings and provide evidence-based foundations for integrated post-disaster interventions targeting smallholder farmers in developing countries.

This paper was written with the aim of analyzing the role of stevedoring workers (TKBM) in loading and unloading activities carried out by the Loading and Unloading Company (PBM) FT. Gelora Perkasa Belawan. In collecting data, the author utilized two approaches, namely field research and library research. Labor efficiency is a key factor in increasing operational productivity in the port sector, however, various problems are often found such as delays, low productivity, and work inefficiencies caused by weak monitoring and performance monitoring systems. In this study, a qualitative approach was used through field methods and library methods, on the operational activities of TKBM in the company. The results of the study indicate that the implementation of structured work and periodic evaluations can improve work discipline, accelerate loading and unloading times, and reduce operational costs. In addition, the role of management in providing constructive feedback and periodic training has also proven effective in supporting labor efficiency. Thus, optimizing the role of TKBM will have a direct impact on improving the performance of PBM PT. Gelora Perkasa Belawan, which ultimately contributes to the smooth flow of goods and economic growth in the Belawan port area.

This study aims to analyze the influence of digital transformation and organizational innovation on sustainability performance, with leadership support and digital literacy as supporting variables and the role of moderating effects in strengthening the relationship between variables. The research method used a quantitative approach with Partial Least Squares–Structural Equation Modeling (PLS- SEM) analysis. Data were collected through a questionnaire measured using reflective indicators for each construct. The results of the measurement model test indicate that all indicators have outer loading values above 0.70, thus being valid in measuring the latent construct. Structurally, digital transformation has a positive effect on sustainability performance with a path coefficient of 0.124,  while organizational innovation shows a relatively weak effect  with a coefficient of 0.006. Leadership support and digital literacy have a fairly strong positive effect on sustainability performance with a coefficient value of 0.586. In addition, the first moderation effect provides a strengthening of the relationship to sustainability performance with a coefficient of 0.154, while the second moderation effect shows a very small effect with a value of 0.032. The R² value of 0.670 indicates that the model is able to explain 67% of the variation in sustainability performance, while the remainder is influenced by other factors outside the research model. These findings confirm that the success of organizational sustainability performance does not only depend on digital transformation and organizational innovation, but is also greatly influenced by leadership support, digital literacy, and moderating mechanisms that strengthen the implementation of digital strategies. This research is expected to provide theoretical and practical contributions to organizations in designing digital- based sustainability strategies.

This study aims to analyze and design the electrical installation requirements for a prototype residential building with dimensions of 11 × 19 meters. The research applies a technical calculation approach based on lighting standards, air conditioning capacity estimation, load analysis, and electrical protection planning. Lighting requirements were determined using the lumen method by considering room area, illumination standards, coefficient of utilization, and light loss factor. Air conditioning capacity was calculated based on room area and standard cooling load values in BTU/hr. Furthermore, total electrical loads were analyzed to determine installed capacity, nominal current, Miniature Circuit Breaker (MCB) ratings, and appropriate cable cross-sectional areas with safety factors applied. The results indicate that proper load grouping, appropriate MCB selection, and correct cable sizing significantly enhance system safety and reliability. The study provides a systematic planning model for residential electrical installations that meets safety, efficiency, and technical standards, and can serve as a reference for similar residential building designs.

The digital transformation of health services through the Mobile JKN application was introduced by BPJS Kesehatan to provide easier access for the public in obtaining information, managing membership administration, and receiving health services more quickly and efficiently. This study aims to measure the readiness level of patients at Abdul Manap Regional Hospital, Jambi City, in adopting the Mobile JKN application using the HOT-Fit method, which covers three main components: Human, Organization, and Technology. Data were collected from 360 respondents through questionnaires and analyzed using Partial Least Square Structural Equation Modeling (PLS-SEM). The results indicate that technology factors—including system quality, information quality, and service quality— along with organizational support have a significant effect on system use and user satisfaction, which in turn positively influence the net benefits. The outer loading values of all indicators exceeded 0.7, with Composite Reliability above 0.8 and AVE above 0.6, confirming that the research instruments are valid and reliable. Overall, patients at Abdul Manap Hospital are categorized as ready to adopt Mobile JKN, although improvements in digital literacy and stronger organizational support are still required to optimize its utilization.

Pyrolysis is a biomass conversion method into fuel through heating at high temperatures under oxygen-limited conditions. The main factors influencing the pyrolysis process include temperature, residence time, pressure, particle size, reactor design, and the type of pyrolysis employed. This study aims to design an auger-type fast pyrolysis system based on previous research. The design and modeling of the fast pyrolysis equipment were carried out using Autodesk Inventor 2021 software. Based on the calculation and design results, a fast pyrolysis reactor with a multi-stage configuration and a capacity of 5.2 kg was developed. The system consists of a three-stage reactor made of Stainless Steel 304. The reactor is equipped with a screw conveyor for material transport, which is driven by an electric motor. Biomass heating inside the reactor is provided by a clamp heater with an electrical power requirement of 611 W, while biomass cooling is performed using a condenser with a cooling water capacity of 15.586 liters. Based on the structural simulation results, the maximum von Mises stress obtained was 35.4 MPa, the maximum displacement was 0.0528 mm, and the safety factor was 6.07 under loading conditions including an internal reactor pressure of 0.32 MPa, a torsional moment of 1,130 kg·mm, and an operating temperature of 700 °C. These values are within the allowable limits of the material, indicating that the designed reactor is structurally safe and feasible for use.

The stability of disposal slopes is a critical aspect of open-pit mining operations because it directly affects operational safety and the continuity of overburden dumping activities. Disposal areas composed of overburden materials generally exhibit heterogeneous characteristics, particularly when soft materials such as mud are present, which can significantly reduce slope stability. Therefore, a comprehensive slope stability evaluation is required prior to further disposal development. This study aims to assess the stability condition of a disposal slope under initial conditions, evaluate the influence of material conditions, and analyze the effectiveness of counterweight application in improving both the safety factor and disposal capacity. The research methodology involved the collection of primary and secondary data, including slope geometry, lithological conditions, and the physical and mechanical properties of disposal materials obtained from laboratory testing and company technical data. Slope stability analysis was performed using the limit equilibrium method with the assistance of geotechnical software, taking into account groundwater conditions and operational loading. The analysis results indicate that the initial disposal condition yielded a safety factor of 0.718, indicating an unstable slope condition. After simulating the removal of mud material, the safety factor increased to 0.907 but remained below acceptable stability criteria. The application of a counterweight significantly improved slope stability, resulting in a safety factor of 1.498. Further optimization through slope geometry redesign produced a final safety factor of 1.101, which satisfies the requirements stipulated in KEPMEN ESDM No. 1827 K/30/MEM/2018. Additionally, the redesign increased the disposal capacity from 119,507,864.23 LCM to 119,682,378.22 LCM, representing an increase of 174,513.99 LCM. These results demonstrate that counterweight application combined with geometric optimization is effective in enhancing both slope stability and disposal capacity.

This study aims to analyze the adaptation of new students to academic workload in higher education and to identify the factors that influence their success or failure. The approach used is qualitative with a literature study. Data were analyzed thematically thru the stages of reduction, display, and conclusion drawing, resulting in key patterns regarding the dynamics of new student adaptation. The results show that the majority of new students experience difficulties in their first semester, especially when the credit load exceeds 20 credits and they are faced with complex assignment demands, periodic exams, and independent time management. This condition triggers academic stress, emotional exhaustion, decreased motivation, and even burnout, contributing to the high dropout rate in the first year. On the other hand, self-efficacy and emotional intelligence have been shown to act as protective factors capable of reducing stress levels and improving the effectiveness of coping strategies. Additionally, comprehensive orientation programs, time management workshops, academic advising, and a supportive campus environment have been proven to improve retention and accelerate the adaptation process. This research concludes that the adaptation of new students is a multidimensional process that requires both personal capacity building and systemic support from the university. The proposed recommendations include phased curriculum design, the development of instrument-based adaptation counselling services, and the implementation of a continuous mentoring program to reduce the risk of adaptation failure and optimize the academic potential of new students.

Plastic waste has become one of the main environmental problems due to its nature, which is difficult to decompose naturally and can cause environmental pollution. One alternative waste treatment method that can be applied is to use a plastic melter to melt and recycle plastic waste into useful products. However, the design of plastic melters often lacks consideration of structural strength and safety aspects during the operation process. This study aims to design and engineer a plastic melter using the Finite Element Analysis (FEA) simulation approach to analyze structural resistance to thermal and mechanical loads that occur during the operation process. The research method was carried out through 3D design modeling of plastic melter components using Solidworks software, followed by analysis with FEA simulation on the main component, namely the melting tube. The parameters analyzed include the distribution of von Mises stress, the amount of displacement, and the safety factor. The analysis results show that the analyzed components experience von Mises stress distribution and displacement that are still below the material tolerance limits, with safety factor values above the recommended safety limits. Thus, the resulting plastic melter design is declared safe and can proceed to the manufacturing process. Therefore, the plastic melter design is safe, strong, and feasible to be realized as an effective and sustainable plastic waste processing technology solution.

This study aims to analyze the effectiveness of bulk cement loading processes on the operational performance of vessels agented by PT. Pelayaran Multi Jaya Samudera Belawan. Bulk cement loading is a complex logistical activity at specialized port terminals that requires intensive coordination between the vessel, agency, and terminal to comply with international safety standards such as the IMSBC Code. The research method used was descriptive qualitative, with data collection techniques including direct field observations, interviews with the company's operational staff, and documentation studies conducted during the internship period. The research findings indicate that loading effectiveness is significantly influenced by the readiness of cargo handling equipment, such as pneumatic or conveyor systems, as well as the timeliness of agency administration in processing ship documents. Although the process generally runs well, obstacles were identified in the form of technical malfunctions of loading equipment and weather factors that frequently hinder operational speed. The conclusion of this research emphasizes that enhancing technical supervision and strengthening communication between the agent and port terminal authorities are crucial to minimizing vessel dwelling time, thereby optimizing operational performance and cost efficiency for ship owners.

Musculoskeletal Disorders (MSDs) are disorders of the skeletal muscles that can range from very mild to very painful. Repeated static loads over a long period of time can cause damage to joints, ligaments, and tendons. Musculoskeletal disorders can occur due to several factors, including occupational factors, individual factors, psychosocial factors, and environmental factors. This study aims to analyze the relationship between age, length of service, and smoking habits with musculoskeletal disorders in furniture craftsmen. This study used an observational analytical study with a cross-sectional design. The sample used a total population of 51 workers. Data collection techniques were observation and filling out the Nordic Body Map (NBM) questionnaire. Data analysis used the Somers'd. The results of the analysis showed that there was a relationship between age (p value = 0.015), length of service (p value = 0.001), and smoking habits (p value = 0.000) with the incidence of Musculoskeletal Disorders (MSDs).