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Sea Surface Temperature (SST) is an important parameter in oceanographic studies because it influences climate dynamics, ocean circulation, and marine ecosystems. Continuous monitoring of SST in open sea areas requires a reliable system capable of operating autonomously. This study develops a solar-powered ocean buoy designed to measure sea surface temperature while simultaneously evaluating the performance of a solar panel as the main energy source. The system uses a DS18B20 sensor to measure SST and an INA219 sensor to monitor the voltage, current, and power of the solar panel, while an ESP32 microcontroller functions as the central data processing unit. The results show that sea surface temperature tends to remain relatively stable with small daily variations, whereas the temperature and performance of the solar panel exhibit larger fluctuations due to direct exposure to solar radiation and changing weather conditions. Solar panel performance also shows significant variations in current and power depending on the intensity of sunlight. To analyze the influence of SST variations on solar panel performance, a statistical analysis using Analysis of Variance (ANOVA) was conducted. The ANOVA results, based on the calculated F-value and the significance value (p-value) at a confidence level of α = 0.05, indicate that SST variations have a significant effect on solar panel performance, demonstrating that the proposed solar-powered buoy system can operate autonomously and has potential for long-term SST monitoring in offshore areas.

Self-Compacting Concrete (SCC) requires a high cement content, which contributes to increased carbon emissions; therefore, this study evaluates the effect of partial cement substitution with fly ash (5%, 10%, and 15%) and the addition of Polyethylene Terephthalate (PET) waste (0.5% and 0.7%) on the mechanical properties of SCC with a target strength of f’c 30 MPa. The research employed laboratory experimental methods, including fresh concrete tests (slump flow, L-box, and V-funnel) and hardened concrete tests (compressive, tensile, and flexural strength) at 7 and 28 days. The results indicate that fly ash substitution enhances compressive strength, with the highest value of 49.59 MPa achieved at 5% fly ash at 28 days, exceeding normal concrete (34.73 MPa). The addition of PET tends to reduce compressive strength due to increased porosity; however, it significantly improves flexural strength, as the combination of 5% fly ash and 0.5% PET achieved 4.7 MPa compared to 2.9 MPa for normal concrete. Overall, the combination of fly ash and PET waste shows potential for application in structural elements requiring high flexural performance.

Time delays and cost overruns remain major problems in building construction projects, particularly in concrete structural works that dominate project duration and cost. This study aims to evaluate the application of re-engineering in concrete structural work methods on the time and cost performance of multi-storey building projects. A quantitative approach using a case study method was employed through comparative analysis between the existing method and alternative methods. The analyzed alternatives include ready-mix concrete with Sika Viscocrete 8007 admixture and semi-system formwork as Alternative I, ready-mix concrete with system formwork as Alternative II, and ready-mix concrete with Sika Viscocrete 8007 admixture combined with system formwork as Alternative III. The results show that all alternatives perform better than the existing method with a duration of 243 days. Alternative I reduced the duration to 208 days with cost efficiency of IDR 55,781,730 or 0.214 percent. Alternative II reduced the duration to 203 days with cost efficiency of IDR 187,553,261 or 0.724 percent. Alternative III achieved the best performance with a duration of 168 days, accelerating 75 days and providing the highest cost efficiency of IDR 243,334,991 or 0.941 percent. The study concludes that re-engineering effectively improves project time and cost performance, with Alternative III as the optimal method.

This research aims to design and develop a prototype wave power plant that utilizes the vertical motion of a buoy as a source of mechanical energy, which is then converted into electrical energy using a recoil starter mechanism. The system is designed to be installed at the stern of a prototype ship. The vertical movement of the buoy caused by ocean waves is transmitted to the recoil starter through a drive rope, producing a stable one-way rotational motion. This rotation is further transmitted to a gearbox to increase rotational speed before driving a DC generator. The electrical energy generated is stored in a 12 VDC battery, supported by a buck–booster converter to stabilize the output voltage. This study employs an experimental engineering approach to evaluate system performance based on empirical test data. The main components of the system include a buoy as a wave energy collector, a recoil starter as the initial rotating mechanism, a DC generator as the electrical energy producer, a buck–booster converter as a voltage regulator, a 12 VDC battery as an energy storage unit, and a monitoring system based on an ESP32 microcontroller integrated with a PZEM-017 sensor. Experimental results show that the recoil starter operates effectively in driving the generator under both no- load and buoy-loaded conditions. Increases in generator rotational speed are directly proportional to increases in output voltage and current. The PZEM-017 sensor demonstrates a high level of measurement accuracy, approaching 100% when compared with a multimeter. Overall, the proposed wave power generation system functions reliably and shows potential for further development as a small-scale alternative renewable energy source.

This study aims to analyze the influence of workforce agility, job satisfaction, and job engagement on employee adaptive performance at PT. MMT Buana Logistik. The dynamic logistics industry requires employees who have high adaptability to technological changes and operational demands. This type of research is quantitative causality with an explanatory approach. The population in this study were all employees of PT. MMT Buana Logistik, totaling 49 people, with the sampling technique used saturated sampling (census). Data were collected through questionnaires with a 5-point Likert scale. Data analysis techniques used included instrument testing (validity and reliability), testing of classical assumptions (normality, multicollinearity, and heteroscedasticity), and multiple linear regression analysis. Hypothesis testing was carried out through t-tests (partial), F-tests (simultaneous) and coefficient of determination (R2). The results showed that workforce agility, job satisfaction, and job engagement partially and simultaneously have a positive and significant influence on employee adaptive performance. These findings imply the importance of managing work flexibility, fulfilling employee satisfaction, and increasing work engagement to build adaptive human resources to support company competitiveness in the logistics industry.  

Generators are one of the important auxiliary aircraft needed on ships for power generation. During the operation of a diesel generator, continuous rotation occurs resulting in friction and erosion of the moving parts. The supporting factor for the smooth running of a diesel engine is a lubrication system that is supported by good lubricating oil quality, besides that it also needs to be supported by an adequate and good cooling system. The use of lubricants is one of the most important factors to ensure the performance of diesel engines. The lubricant is in charge of maintaining the condition of the engine so that it remains stable. This study aims to analyze the effect of using lubricating oil beyond the operating hours limit on engine heat. Furthermore, it also discusses steps to ensure diesel engine temperatures remain normal. This research was carried out during the practice of sailing on a ship for approximately one year. This study uses a descriptive quantitative research method. The primary data obtained directly utilizes observation methods, and documentation. Secondary data was obtained from existing articles and journals. The data analysis techniques used are descriptive analysis and inferential analysis. The results of this study show that the working hours of lubricating oil use have a significant influence on the increase in the temperature of diesel generator engines as evidenced by hypothesis tests on two engine units, namely AE1 and AE2. In the AE1 unit, a t-value of 18.467 with a significance of 0.000 was obtained, while in AE2 the t-value was 14.289 with a significance of 0.000. The significance value in both units is less than 0.05 so it can be concluded that the working hours of lubricated oil have a significant influence on the temperature of the genarato diesel engine on the ship.

Urban waste management has become a complex challenge due to population growth, urbanization, and economic activities contributing to higher waste generation. Effective waste management systems are required to reduce waste disposed at final disposal sites. This study aims to evaluate the effectiveness of waste management at the TPS 3R Pedalangan Bersinar facility in Semarang City by examining waste separation from the source. The research applied a quantitative approach using mass balance analysis to assess the balance between incoming waste, processed waste, and residual waste in the system. Primary data were collected through field observations, interviews, and operational monitoring for six consecutive days, while secondary data were obtained from the Semarang Environmental Agency. Results show community-based waste banks in Pedalangan demonstrate a high level of effectiveness with a recovery factor reaching 100%, indicating optimal recycling performance and strong community participation. Meanwhile, the TPS 3R facility processes an average waste volume of 16.61 m³/day with reduction of 10.32 m³/day and residual waste of 6.29 m³/day, resulting in a recovery factor of approximately 0.62 categorized as moderate effectiveness. Therefore, strengthening household waste separation, improving operational management, and increasing community participation are recommended to enhance waste reduction and support sustainable urban waste management systems.

This study aims to analyze the technical and economic impact of power evacuation work on the 20 kV distribution system at PT PLN (Persero) UP3 East Bali. The main problem studied is the high losses and poor voltage profile on the downstream side of the Kintamani feeder. The method used is load flow simulation using ETAP software with a comparative approach to conditions before and after power evacuation. The results showed that the active losses decreased from 1.017 MW to 0.626 MW (efficiency 38.45%), accompanied by an increase in the end voltage from 16.32 kV to 18.72 kV and 19.38 kV, thus meeting the SPLN 1:1995 standard. The reduction in losses resulted in energy savings of 3,425,160 kWh/year. From the economic side, a payback period (PBP) of 1.40 years was obtained, which shows that the project is financially feasible. In addition, the improvement of network performance also contributes to the reliability of the distribution system and the continuity of the distribution of electrical energy to customers. Thus, power evacuation work has been proven to be effective in improving power distribution efficiency, improving voltage quality, and providing significant economic benefits.

Healthcare is an integral part of health development in Indonesia, which aims to optimally improve public health. Hospitals, as healthcare facilities, are required to provide quality, safe, and patient-centered services. Service quality is a key indicator of service success, as good service impacts patient satisfaction. One of the most important services in hospitals is obstetrics, which directly relates to maternal and infant health, making patient satisfaction a crucial aspect. Midwives, as professional healthcare workers, play a strategic role in providing comprehensive, sustainable, and patient-centered midwifery care. This study aims to analyze the influence of healthcare facilities and midwife performance on patient satisfaction through service quality. The method used is a quantitative study with an analytical approach and a cross-sectional design. The results of the multiple linear regression test indicate that midwife performance has a more dominant influence on service quality than healthcare facilities. Meanwhile, regarding patient satisfaction, service quality is the most dominant factor, followed by midwife performance and healthcare facilities. The conclusion of this study is that service quality reflects the overall patient experience and is a key factor in improving patient satisfaction.

Population growth and socio-economic activities increase traffic volume, affecting the performance of the Raden Kusno – A. Djaelani – Sujarwo signalized intersection. This study aims to analyze the intersection’s current performance, estimate its condition over the next five years, and formulate alternative treatment strategies. The research data include geometric characteristics, signal timing, vehicle speed, and traffic volume obtained from CCTV recording over a three-day observation period from moning to evening, as well as population and vehicle data for projection. The intersection performance was analyzed using the PKJI 2023 approach and VISSIM simulation. Under current conditions, the intersection operates at LOS E with delays of 45,12 seconds (PKJI 2023) dan 60,56 seconds (VISSIM). In the five-year projection, delays increase to 48,97 seconds with LOS E (PKJI 2023) and 131,29 seconds with LOS F (VISSIM). Modifying the signal from four to three phases with a 70-second cycle improves the current condition to LOS C, with delays of 24,50 seconds (PKJI 2023) and 29,43 seconds (VISSIM). For the five-year projection, adding a continuous left-turn lane results in LOS D with 27,04 seconds (PKJI 2023) and LOS C with 32,01 seconds (VISSIM).

The increasingly complex global energy problem drives the need for efficient, low-cost, and environmentally friendly energy storage systems. This study aims to analyze the power performance of two symmetric supercapacitor prototypes using Nitrogen-doped Graphene-Like Carbon (N-GLC) as the electrode material and 1 M  as the electrolyte, with different electrode substrates: aluminum and copper. Both prototypes were tested through charging and discharging processes using resistive loads of 470 ohms and 560 ohms for 5 minutes. The analyzed parameters include voltage, current, power, and output energy. The results show that the aluminum electrode achieved a higher maximum charging power of up to 18 mW; however, its energy discharge efficiency was very low at only 0.87%. In contrast, the copper electrode demonstrated a more balanced charging and discharging performance with an energy discharge efficiency of 19.4%. Analysis also indicates that the copper substrate maintains better voltage stability after 6 hours of storage compared to aluminum, which experienced significant degradation. Thus, the copper electrode is superior in maintaining the power and stability of a simple N-GLC-based symmetric supercapacitor system.

Indonesia is in an earthquake-prone region, therefore, designing building constructions that can withstand seismic loads is crucial in civil engineering. Reinforced concrete shear walls are one of the vertical structural fundamentals that are effectively used in multi-story buildings to withstand lateral forces due to earthquake and wind loads. Structures that use shear walls can increase stiffness and reduce horizontal deviations (deflections) of buildings, which contribute to the stability and safety of structures based on the SNI 1726:2019 standard. This study aims to analyze the effect of shear wall configurations on deviation and torsion requirements in multi-story building planning. The study object is a 6-story reinforced concrete building model in a specific earthquake zone. The design and modeling were performed using structural analysis software, taking into account columns, beams, slabs, and shear walls. The analysis results show that optimal placement of shear walls at the building edges significantly reduces horizontal drift, torsion, and shear forces, and improves the structural performance level compared to structures without shear walls or those with less effective placement. Structures with shear walls have optimal stiffness in absorbing lateral forces, making them more resistant to damage from the planned earthquake.

This study aims to comprehensively examine the concept of intention and the recitation of Surah Al-Fatihah in prayer from the perspective of the four imams of the schools of jurisprudence: Hanafi, Maliki, Shafi’i, and Hanbali. The background of this study is based on the existence of differing opinions among scholars, which often cause confusion among the public regarding the correct practice of prayer. The method used is qualitative research in the form of a literature review (library research), through data collection from classical fiqh texts, scientific journals, and other relevant literature. The data analysis technique employs a descriptive-comparative approach to identify the similarities and differences in the views of each school of thought. The results of the study indicate that all schools of thought agree that intention is an act of the heart that constitutes a valid condition for prayer, yet they differ regarding the timing of its performance and its verbalization. Regarding the recitation of Surah Al-Fatihah, the Shafi’i school mandates it as a pillar in every rak’ah, whereas the Hanafi school does not consider it a pillar. The Maliki and Hanbali schools adopt a moderate stance by granting leniency under certain conditions. These differences reflect the richness of Islamic jurisprudence, which is dynamic and flexible. This study is expected to provide a more comprehensive understanding and foster an attitude of tolerance in addressing differences in worship practices.

This study aims to analyze the financial distress condition of PT Garuda Indonesia (Persero) Tbk during the period 2015–2024 using the Springate and Grover models. The research employs a quantitative descriptive approach with secondary data obtained from the company’s annual financial statements. Financial distress analysis is conducted by calculating financial ratios included in each model to describe the company’s financial condition over the observation period. The results indicate that PT Garuda Indonesia (Persero) Tbk experienced financial distress during several periods, particularly before and during the COVID-19 pandemic, which was reflected in weakened liquidity, declining profitability, and reduced efficiency in asset utilization. However, following the financial restructuring process after 2021, both the Springate and Grover models show an improvement in the company’s financial condition, indicating a transition toward a more stable non-distress status. Although the Springate and Grover models use different financial indicators and classification approaches, both are able to descriptively capture the dynamics of financial distress experienced by the company. The differences in classification results reflect the distinct focus of each model, where the Springate model is more sensitive to liquidity and operational performance, while the Grover model emphasizes asset profitability. Therefore, the combined use of both models provides a more comprehensive overview of the financial distress condition of PT Garuda Indonesia (Persero) Tbk during the research period.

The low thermal efficiency of Gas Power Plants (PLTG) due to exhaust gas heat loss drives the implementation of cogeneration at PLTGU Block II PT. PLN Indonesia Power UBP Semarang. This study analyzes the performance of the Gas Turbine Generator (GTG), combined cycle efficiency, and Exergy distribution using a 3-3-1 configuration. The research utilizes actual operational data from January 28, 2026, sampled at 10-minute intervals. Results indicate that cogeneration via a Heat Recovery Steam Generator (HRSG) significantly enhances plant efficiency. The GTG output ranged from 273–283 MW with an efficiency of 30.0–30.2%. Following combined cycle integration, system efficiency increased to 43.9–44.4%, a gain of approximately 14%, with a heat rate of 11,916–11,988 kJ/kWh. Exhaust heat of 665–713 MW was recovered to generate an additional 130 MW through the Steam Turbine Generator (STG). Exergy analysis reveals that the largest irreversibility occurs in the GTG combustion process (285 MW), followed by the HRSG (185 MW) and STG (49 MW).

This study aims to analyze the influence of organizational culture on employee performance through job satisfaction at the Banda Aceh City Environmental, Sanitation, and Beautification Office. This study employs a quantitative approach using an associative method. The study population consisted of 44 civil servants, all of whom were included in the sample using a census method. Data collection was conducted via a questionnaire using a Likert scale, supplemented by observations and interviews. The data analysis techniques employed included path analysis, t-tests, the coefficient of determination (R²), and the Sobel test to examine the mediating role. The results of the study indicate that organizational culture has a positive and significant effect on employee performance, with a significance value of 0.004 and a calculated t-value of 3.014. Organizational culture also has a positive and significant effect on job satisfaction, with a p-value of 0.003 and a t-statistic of 3.940. Furthermore, job satisfaction has a positive and significant effect on employee performance with a significance value of 0.000 and a t-value of 5.174. A mediation test using the Sobel test indicates that job satisfaction significantly mediates the effect of organizational culture on employee performance with a t-value of 3.818 (>1.96). The coefficient of determination of 0.832 indicates that 83.2% of the variation in employee performance can be explained by organizational culture, job satisfaction, and their interaction, while the remainder is influenced by other variables outside the scope of this study. Thus, it can be concluded that organizational culture has a strong influence on improving employee performance, both directly and through job satisfaction as a mediating variable.

The implementation of Hospital Management Information Systems (HMIS) has become a strategic imperative to enhance operational efficiency amidst the ongoing global digital health transformation era. This study aims to analyze the determinants of successful HMIS implementation and its impact on service efficiency and patient outcome quality. Employing a narrative review approach with thematic synthesis of literature from PubMed, Scopus, and ScienceDirect databases between 2016-2026, the study evaluates the relationship between technology investment and organizational performance. The synthesis results indicate that while HMIS significantly reduces administrative burdens and medication errors, a "digital paradox" exists where technical efficiency may disrupt interpersonal interactions between healthcare providers and patients if systems are not user-centered. Key success factors include data interoperability (HL7/FHIR standards), human resource readiness, and governance policy support. This study concludes that a patient-centered efficiency model is the fundamental basis for ensuring technology investments yield sustainable added value within the healthcare delivery system.

Work motivation, job satisfaction, and employee performance are key aspects of management psychology that continue to evolve as organizational productivity demands increase. In an era of global competition, organizations are required to manage human resources effectively by enhancing work motivation and job satisfaction to achieve optimal performance. This study aims to examine the relationship between work motivation and employee performance, as well as to analyze the role of job satisfaction as a mediating variable in that relationship. The method used is a literature review with a qualitative approach. Data were collected through the Google Scholar and Publish or Perish databases using keywords related to work motivation, job satisfaction, and employee performance from a management psychology perspective. From 25 articles found between 2022 and 2026, 5 of the most relevant articles were selected for further analysis.The results of the study indicate that work motivation has a significant influence on employee performance, both directly and indirectly through job satisfaction as a mediating variable. Additionally, there is a growing trend toward the integration of management psychology approaches in efforts to enhance employee performance. Thus, it can be concluded that the simultaneous management of motivation and job satisfaction is a key factor in achieving optimal performance. Further research is recommended to develop a more comprehensive and integrative model.

This study is motivated by the importance of improving the performance of police officers as the frontline of public service, which is influenced by transformational leadership, organizational communication, and work discipline. In practice, variations in officer performance are still observed at police precincts under the Solok Police Department, as evidenced by differences in case resolution rates, service responsiveness, and the effectiveness of task execution. These conditions are suspected to be related to the suboptimal implementation of transformational leadership, organizational communication, and work discipline among officers. This study aims to analyze the influence of transformational leadership and organizational communication on police officer performance, as well as to test the role of work discipline as a moderating variable. The research method used is a quantitative approach with a field research design. The study population consisted of all 126 members of the police stations under the Solok Police Department, with a sample size of 124 respondents. Data collection was conducted by distributing questionnaires to police officers, which were then analyzed using the Partial Least Squares–Structural Equation Modeling (PLS-SEM) method. The results of the study indicate that transformational leadership has a positive and significant effect on member performance, with a coefficient of 0.754, a T-statistic of 3.550 (>1.96), and a P-value of 0.000 (<0.05); thus, the first hypothesis is accepted. Organizational communication has a negative and significant effect on performance with a coefficient of -0.615, a T-statistic of 2.509 (>1.96), and a P-value of 0.012 (<0.05). Work discipline does not moderate the effects of transformational leadership or organizational communication on performance, as both show insignificant results. In conclusion, improved police officer performance can be achieved through the implementation of effective transformational leadership and the strengthening of organizational communication.

This study aims to investigate the influence of Work Environment, Workload, and Leadership Style on Job Satisfaction among Non -Medical Employees at Daya Medika Clinic in West Jakarta. This study used a Likert-scale questionnaire and involved a sample of 43 employees using a non-probability sampling method and saturated sampling technique. The results of a multiple linear regression analysis using SPSS version 26 indicate that Work Environment has a positive and significant effect on Employee Job Satisfaction, Workload has no significant effect on Employee Job Satisfaction, while Leadership Style has a positive and significant effect on Employee Job Satisfaction. These findings provide insights for Daya Medika Clinic management in improving the quality of the work environment and implementing appropriate leadership styles to enhance employee job satisfaction. These findings have practical implications for improving employee performance and organizational effectiveness, and serve as a reference for further research in the field of human resource management.