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The purpose of this study was to determine the direct influence of work motivation on work ethic and ethical responsibility, the influence of ethical responsibility on work ethic, and the indirect influence of work motivation on work ethic through ethical responsibility as an intervening variable on employees at the Human Resources Development Agency of Jambi Province. The method used was quantitative research. The results of the study showed that work motivation towards work ethic had a significance value of 0.000 (P <0.05), work motivation towards ethical responsibility had a significance value of 0.000 (P <0.05), and ethical responsibility towards work ethic had a significance value of 0.000 (P <0.05). Furthermore, the indirect effect of work motivation on work ethic through the ethics of responsibility has a significance value of 0.000 (P <0.05), so that work motivation influences work ethic through the ethics of responsibility as an intervening variable. In conclusion, work motivation influences work ethic through the ethics of responsibility as an intervening variable for employees at the Human Resources Development Agency of Jambi Province.

Vegetables are food commodities widely consumed by the public due to their high nutritional content. Chili (Capsicum annuum L.), green beans (Phaseolus vulgaris L.), and Chinese cabbage (Brassica pekinensia L.) are among the vegetables that can be processed into various delicious dishes or consumed fresh as raw vegetables. To obtain healthy and high-quality vegetable crops, pesticides are commonly used to control pests that may damage the plants. One of the widely used pesticides is chlorpyrifos, which can leave residues that may pose both acute and chronic health risks. Therefore, it is necessary to analyze the levels of chlorpyrifos pesticide residues in vegetables. The residue levels were determined using a UV-Vis spectrophotometer at a wavelength of 230 nm with dichloromethane as the solvent, while qualitative analysis was performed using HPLC by comparing the retention times of standard solutions and vegetable samples. In this study, washing treatments were applied to the vegetables using dichloromethane, distilled water, well water, and tap water (PDAM) to evaluate the effect of washing on pesticide residue levels. The concentrations of pesticide residues in unwashed vegetables were chili (2.6680 ± 0.0214 mg/kg), green beans (2.4658 ± 0.0193 mg/kg), and Chinese cabbage (2.7950 ± 0.0379 mg/kg). The washing process was carried out three times for each solvent. After three washings using dichloromethane and distilled water, pesticide residues were no longer detected, whereas washing with tap water (PDAM) and well water still left residues, although at levels much lower than the Maximum Residue Limit (MRL). The health risk assessment showed that the aHQ and cHQ values were < 1, indicating that consumption within the recommended limits of these samples does not pose health risks, either in the short term or long term. This study provides important information that repeated washing is necessary to effectively reduce pesticide residue levels in vegetables before consumption.  

Modern infrastructure development often involves the use of mass concrete in large structural elements such as pile caps and foundations. However, massive concrete volumes trigger a significant temperature increase due to the heat of hydration that is difficult to dissipate, posing a risk of thermal stress and structural cracking. This study aims to analyze the temperature rise behavior of mass concrete and evaluate the effectiveness of combining chilled water and fly ash substitution in minimizing these thermal cracking risks.The research method employs a quantitative approach through laboratory testing at PT Adhimix RMC Plant Kaligawe. Specimen blocks measuring 40 x 40 x 100 cm were divided into three variations: normal concrete (BN), concrete with chilled water and 15% fly ash (BAF), and concrete with 25% fly ash (BF). Temperature was monitored using thermocouples at the core and surface for 14 days, then validated using the Portland Cement Association (PCA) formula. The results indicate that the integration of chilled water with 15% fly ash and the use of 25% fly ash significantly controlled extreme temperature surges at the 5th hour. The combination of chilled water and 15% fly ash produced the lowest core temperature of 37.3°C, far below the control concrete which reached 62.4°C. This proves that the combination of precooling methods and fly ash substitution is effective in reducing the heat of hydration during the early hardening period, although the use of 25% fly ash was found to be more stable in maintaining mass concrete temperature.

This study aims to analyze the effect of direct learning on engine components toward students' vehicle diagnostic abilities in vocational education. Employing a quantitative approach with an ex post facto design, the sample consisted of 80 students selected using simple random sampling from a population of 100 students. Data were collected using validated and reliable questionnaires. The data analysis techniques included descriptive statistics, classical assumption tests, and simple linear regression analysis. The results show that direct learning has a positive and significant effect on students’ vehicle diagnostic abilities, with a significance value of 0.000 < 0.05 and a coefficient of determination (R²) of 0.264. This indicates that direct learning contributes 26.4% to the improvement of students' diagnostic abilities. The findings emphasize the importance of practical, hands-on learning approaches in vocational education. These approaches not only enhance students' understanding of automotive theory but also improve their diagnostic skills. The study highlights that systematic learning and direct interaction with engine components are key factors in developing students' competencies, making them more effective in real-world vehicle diagnostics.

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.

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.

Air transportation plays an important role in supporting mobility, tourism, and emergency activities such as medical evacuation and search and rescue (SAR). One of the essential supporting facilities for helicopter operations is a heliport, which must meet safety standards, including an adequate lighting system. This study aims to design an LED floodlight installation system for the Main Helipad of Fly Bali Heliport based on the international standard ICAO Annex 14 Volume II, while considering the corrosive coastal environmental conditions. The research method used is an engineering design approach with quantitative analysis of illumination requirements and current carrying capacity (CCC). Data were obtained through literature studies based on ICAO, FAA, and CAP 437 standards, as well as field observations. The design process includes determining the number and placement of floodlights, technical specifications, and electrical installation systems, including cable and protection selection. The results show that the configuration of four LED floodlight units is capable of producing a minimum illumination of 10 lux evenly across the TLOF and FATO areas in accordance with ICAO standards without causing glare. The use of Avlite AV-HL-FL floodlights with IP66 protection is suitable for coastal environments. The electrical installation system using NYY 2×2.5 mm² cables and a 2 Ampere MCB ensures system safety and reliability. Therefore, this design can enhance heliport operational safety and support optimal night operations.

The growth of aviation activities at I Gusti Ngurah Rai International Airport, Bali, has led to the rapid development of surrounding areas, potentially obstructing protected airspace. Obstacles on the approach surface of Runway 27 have become a critical concern, particularly for precision approach Category II (CAT II) operations, which require obstacle-free approach areas. This study aims to analyze obstacles within the approach area of Runway 27 and develop effective control strategies. Using a descriptive qualitative approach, data was collected through field observations, interviews, and documentation studies. The analysis follows the Obstacle Limitation Surfaces (OLS) standards according to ICAO and national regulations. The findings reveal obstacles such as mangrove vegetation, antennas, and ship activities in the Benoa Harbor area, which are located within the approach surface and could potentially impact the OLS limits. While these obstacles generally comply with existing regulations, their proximity to the threshold may reduce the safety margin of flight operations and limit CAT II implementation on Runway 27. This study proposes technical, operational, regulatory, and preventive strategies to improve obstacle control, enhancing aviation safety and ensuring the readiness for CAT II operations at the airport.

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.

Coastal areas are highly dynamic and increasingly exposed to physical pressures such as coastal erosion, shoreline change, inundation, and sea-level rise. In Indonesia, most coastal vulnerability studies remain focused on physical mapping and have not been systematically integrated with spatial planning evaluation. This study aims to analyze physical coastal vulnerability using the Coastal Vulnerability Index (CVI) and integrate the results with the Regional Spatial Plan (RTRW) in the coastal areas of Mangarabombang and Laikang Sub-districts, Takalar Regency. A quantitative spatial approach was applied using eight parameters, which were reclassified into vulnerability scores, transformed into CVI values, and classified using quartile methods. The results show that high and very high vulnerability classes dominate the coastal area. Spatial integration reveals that several development zones intersect with high vulnerability levels, indicating potential spatial mismatch. This study confirms that CVI can be operationalized as a spatial evaluation tool to support adaptive and risk-based coastal planning.

The problem of urban flooding is a growing issue due to high population density, increasing volumes of plastic waste, and the reduction of water absorption areas. The use of conventional paving blocks, which are impermeable, further exacerbates flooding conditions because they do not allow water to infiltrate into the soil. This study aims to develop an innovative plastic waste-based paving block incorporating rice straw and sugarcane bagasse, along with the integration of phytoremediation concepts as a solution for urban flood mitigation. The method employed was an experimental approach involving the following stages: material preparation, plastic incineration, material mixing, molding, and testing of water absorption capacity and compressive strength. The results showed that paving blocks with a combination of plastic waste, rice straw, and sugarcane bagasse had the highest water absorption rate of 34% and compressive strength of 21 kg/cm², meeting SNI standards. The addition of natural materials containing silica was proven to enhance the material’s porosity and strength. Additionally, the application of phytoremediation using water hyacinth has the potential to improve the quality of water seeping into the soil. Thus, this phytoremediation-based paving block innovation can serve as an effective alternative solution to reduce flood risks while supporting sustainable waste management and environmental stewardship.

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.

The amalgamation and flotation methods are widely used by miners because the methods are simple, fast and easy. The purpose of this study was aims to test the effectiveness of gold recovery using the amalgamation and flotation methods in conventional gold processing. The research methods used were observation and testing using the amalgamation and flotation methods in conventional gold processing. The effectiveness analysis was carried out by calculating the percentage of gold produced in the amalgamation and flotation processing methods. The test was carried out on 10 samples, each weighing 10 kg. The amalgamation process used a Hg solution, while flotation used a detergent reagent. The total primary gold processing using the amalgamation method was 11.46 grams, while the total primary gold recovery using the flotation method was 12.15 grams. The results of gold processing using the flotation method were higher than those using amalgamation because flotation can separate gold more efficiently from ore containing various impurity minerals. Meanwhile, the amalgamation method, which uses mercury, tends to be less effective and loses some of the gold because it only binds very fine and dispersed gold particles, while flotation can handle ore with lower gold content and larger gold particles.

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.

This research aims to analyze the influence of thermal conditions; specifically the temperature difference between the test object and the environment; on the characteristics of air flow and heat transfer around it. The object of this study is a test piece subjected to free air flow under various temperature conditions; focusing on the convection heat transfer phenomenon. The main problem addressed is how temperature variations affect the convection heat transfer coefficient; heat transfer rate; and heat flux; as well as changes in air velocity and pressure profiles. Therefore; the objective of this research is to quantitatively compare and assess these thermal and fluid parameters through an experimental study approach and Computational Fluid Dynamics (CFD) simulation. The methodology involves direct measurement of temperature and pressure parameters under low and high-temperature conditions; which are then processed to determine the convection coefficient (); heat transfer rate (); and heat flux (). The main findings indicate that at low-temperature conditions; the heat transfer coefficient () was found to be 53.26 ; the heat transfer rate () was 24.99 W; and the heat flux () was 537.87 ; with a pressure drop of 0.86 Pa. In conclusion; thermal conditions play a crucial role in determining the dynamics of air flow and the efficiency of heat transfer; the greater the temperature difference (); the higher the potential heat transfer rate; establishing a strong correlation between thermal conditions and the convection phenomenon.

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).

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.

Takaras River is a river basin that is vulnerable to pollution, particularly from the mercury usage in small-scale gold mining. This study aims to identify water quality based on mercury (Hg)and pH levels in the Takaras River. Samples were taken at two locations using a purposive sampling method. Results showed indications of mercury use on former gold mining land around the Takaras River altought the mercury content level was below 0.075 µg/L or 0.00075 mg/L in sample 1 and 2. Based on the test results, the acidity level (pH) in the two water samples from Takaras River is 3.86 and 3.84 in sample 1 and 2, compared to the maximum pH quality standard of 6-9 for Class II water, it is concluded that the scale of acidity in Takaras River is very low, indicating that the water quality in the Takaras River is highly acidic, abnormal, and shows signs of serious pollution. The implications of low pH levels in the Takaras River can cause damage to the Takaras River ecosystem, a decline in soil quality and fertility, and an increase in heavy metal toxicity in the environment surrounding the river.

The coal mining industry requires accurate stockpile volume measurements for inventory and production reporting. Conventional methods have limitations in accuracy, efficiency, and safety. This study compares the accuracy and efficiency of coal stockpile volume measurements using a Terrestrial Laser Scanner (TLS) Leica MS60 and an Unmanned Aerial Vehicle (UAV) DJI Matrice 4E, validated by the ASTM D6172-98 standard. Conducted on five Run of Mine (ROM) coal stockpiles covering 13,500 m² at PT XYZ, Lahat, South Sumatra, the TLS method used 43 scan positions, while the UAV employed 430 aerial images with specific flight parameters. Data were processed using Leica Infinity, Surpac, and Agisoft Metashape. The results showed volumes of 94,076 m³ (TLS) and 94,965 m³ (UAV), with a difference of 889 m³ (0.95%). Volume deviations ranged from 0.48% to 1.89%, with an average of 1.42%, all within the ASTM tolerance (<2%). Time efficiency analysis revealed that the UAV method required 200 minutes (3.33 hours), saving 63.3% (approximately 6.17 hours) compared to the TLS method (570 minutes). The largest efficiency gain occurred during field data acquisition, with an 85% reduction in time. This study confirms UAV photogrammetry as a valid, accurate, and efficient alternative for coal stockpile volume measurement in mining.

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.