Publication Search

The rapid growth of Solar Power Plant (PLTS) installations in Indonesia faces efficiency challenges due to the continuously changing position of the sun. Fixed panel systems cannot absorb solar radiation optimally throughout the day. This study aims to evaluate and compare the efficiency of various solar tracking system methods developed over the last five years using a simple literature review approach. The research method was conducted by collecting, screening, and synthesizing secondary data from five reputable scientific journals using a synthesis matrix. The review results indicate that single-axis tracking systems increase power efficiency by 15% to 24.5%. Meanwhile, dual-axis systems achieve higher efficiency, ranging from 30% to 35%, by tracking both horizontal and vertical solar movements. In terms of control systems, astronomical algorithms are found to be more reliable in cloudy weather conditions than pure light sensors. However, the internal power consumption of the actuator motors remains a critical factor that can reduce the system's net energy gain. The implication of this study emphasizes the importance of shifting future research focus toward energy-saving algorithm optimization to maximize net power yield in dynamic solar panel implementations.

concern for pet owners. Consequently, cat owners seek equipment that can support and simplify their daily pet care activities. However, the busy schedules of many cat owners often make it difficult for them to provide consistent care, raising concerns about the neglect of their pets. To address this issue, this study developed an automatic cat feeding system for a cat enclosure using an experimental research method. The proposed system utilizes a load cell sensor, a Real-Time Clock (RTC), a servo motor, and an ATmega16 microcontroller. The load cell sensor is employed to determine the appropriate food portion based on the cat's nutritional requirements, while the RTC controls the feeding schedule by dispensing food twice a day at predetermined times. The experimental results demonstrate that the system was successfully implemented, with the load cell measurement exhibiting an error rate of 10.71% relative to the predefined set point. Furthermore, the servo motor effectively controlled the valve mechanism, achieving a maximum opening angle of 85 degrees. Overall, the developed system performed reliably and met the expected operational objectives..

Children with special needs, particularly those with intellectual disabilities, often experience difficulties in emotional development, communication skills, and social interaction. These conditions may make it challenging for them to express their feelings, regulate their emotions, and adapt to their surroundings. Based on observations conducted at SLBN Pembina Kupang, several children were found to be easily angered, lacking in self-confidence, and experiencing difficulties in social interaction. The implementation of this program consisted of three stages: preparation, implementation, and evaluation. The program began with coordination with the school, the preparation of coloring materials and equipment, and the selection of participants. Subsequently, the children participated in play therapy through coloring activities under the guidance of the service team and teachers. Evaluation was carried out by observing the children's participation, changes in emotional expression, and social interaction skills throughout the activities. The results showed that play therapy through coloring activities had a positive impact on the children's emotional development. The children became calmer, more confident, and better able to express their feelings. In addition, the activities helped improve their social skills, cooperation, concentration, discipline, and fine motor skills. Therefore, play therapy through coloring activities can serve as an effective, simple, and sustainable intervention to support the emotional development of children with special needs at SLBN Pembina Kupang.

Early Childhood Education (PAUD) is a stage of education that plays a crucial role in maximizing children's cognitive, social-emotional, motor skills, and creativity growth at their peak developmental stage. Children aged three to six learn efficiently through play, hands-on exploration, and interaction with their surroundings. The purpose of this study was to evaluate the use of loose parts media based on natural materials as a means to stimulate creativity in early childhood at PAUD Pelita Mandiri Kertek. This study adopted a descriptive qualitative approach and utilized data collection techniques such as observation, in-depth interviews with teachers, and documentation of children's work. The main focus of this study was on the use of various natural materials, such as corn cobs, twigs, pebbles, and leaves, in play and learning activities. The results showed that loose parts media using natural materials can enhance children's creativity by improving problem-solving skills, strengthening verbal skills in expressing ideas and telling stories about their work, and supporting independent learning because children are actively involved in the educational process. The open-ended nature of the materials allows children to explore and express their ideas freely, thus creating a learning atmosphere full of creativity, innovation, and fun. The implications of this research indicate that the use of loose parts media based on natural materials can be an alternative learning method that is not only effective, but also economical and easy to implement to support the development of children's creativity, independence, and thinking skills, in line with the principles of child-centered learning.

The rapid development of digital service platforms, particularly online motorcycle taxi services, has transformed modern economic transaction patterns, where the relationship between drivers and consumers is categorized as an ijarah (service lease) contract. However, in practice, various forms of breach of contract (wanprestasi) frequently occur and potentially harm one of the parties. This study aims to analyze the concept of the ijarah contract, identify the forms of wanprestasi, and review them based on Sharia Economic Law principles. This qualitative normative research employs a literature-based approach, utilizing secondary data from classical fiqh books, DSN-MUI fatwas, the Indonesian Civil Code, and reputable academic journals, which are analyzed descriptively-analytically. The findings reveal that breaches occur in three typologies: unilateral cancellation by consumers (ta'addi), negligence and fictitious account manipulation by drivers (taqshir and tadlis), and disproportionate cancel fee policies by platforms, indicating structural dzulm. From a sharia perspective, the settlement of wanprestasi requires compensation (ta'widh) calculated based on actual loss without riba elements, while classifying technical obstacles as force majeure under a fault-based liability approach. This study implies the need to reconstruct the digital ecosystem so that it is not only formally valid but also enforces substantive justice based on maslahah (public interest), al-‘adl (justice), mas,uliyyah (responsibility), and tawazun (proportional balance)

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.

The development of electric vehicle technology has encouraged the use of electric bicycles as an environmentally friendly and energy-efficient mode of transportation. One of the main components of an electric bicycle is the hub BLDC (Brushless Direct Current) motor, which is considered more efficient because it is directly integrated into the wheel without requiring a chain transmission system. However, the performance of the hub BLDC motor is affected by operating conditions, particularly variations in load and speed, which influence current consumption and overall electrical performance. This study aimed to analyze the effect of load and speed variations on the current consumption of a hub BLDC motor. A quantitative experimental method was employed by conducting direct tests on an electric bicycle using load variations of 50 kg, 60 kg, and 70 kg, as well as speed variations of 30 km/h, 35 km/h, and 40 km/h. Current measurements were carried out in real time using a PZEM 051 sensor, and the collected data were analyzed using average values obtained from repeated measurements. The results showed that increasing the load and speed led to higher current consumption of the hub BLDC motor, from 4.6 A to 5.0 A under load variation and from 4.5 A to 5.1 A under speed variation. These findings indicate that both load and speed significantly affect the electrical current required by the hub BLDC motor, demonstrating that greater operating demands result in higher energy consumption.

This research is motivated by the development of injection motorcycle engine management system technology that demands increased performance through optimization of the Electronic Control Unit (ECU). This study aims to analyze the performance comparison of the Yamaha MX King 180 cc using a standard ECU and a racing ECU on engine power and torque. The method used is an experiment with engine dynotest testing in the range of 6000-10000 RPM. The research sample is a 2015 Yamaha MX King unit that has been modified to 180 cc. Data were collected through direct measurements of power (HP) and torque (Nm), then analyzed descriptively in the form of tables and graphs. The results show that the racing ECU is able to produce a higher maximum power of 24.9 HP at 10000 RPM compared to the standard ECU of 22.2 HP at the same engine speed. In terms of torque, both types of ECU reach peak values ​​at 8000 RPM with a relatively small difference (18.18 Nm on the standard ECU and 18.15 Nm on the racing ECU). However, at low to mid-range revs, the racing ECU tends to produce slightly more torque, although at very high revs, it experiences a greater decrease compared to the standard ECU. The racing ECU excels at increasing high-rev power, while the standard ECU exhibits more consistent torque stability. Therefore, the choice of ECU type must be tailored to the performance requirements and the characteristics of the vehicle's use.

Braking performance is an important aspect of motorcycle safety because it relates to the vehicle’s ability to reduce speed and stop properly. In a hydraulic disc brake system, braking is influenced by mechanical and hydraulic factors, especially disc brake diameter and master cylinder pressure. Disc brake diameter determines the effective braking radius, while master cylinder pressure generates hydraulic pressure that is transmitted to the caliper. This study aims to analyze the effect of disc brake diameter and master cylinder pressure variations on the braking distance and braking time of a 110 cc motorcycle. This research used a quantitative experimental method with a Honda Revo Injection 110 cc motorcycle as the test object. The disc brake diameter variations were 190 mm, 220 mm, and 260 mm, while the master cylinder pressures were 2 bar, 4 bar, and 6 bar. Each treatment combination was tested three times at an initial speed of 40 km/h on a dry and flat asphalt road. Braking distance was obtained from front wheel rotation data recorded by a magnetic digital counter, while braking time was determined from video recordings. The data were analyzed using Two-Way ANOVA and response optimization. The results showed that increasing disc brake diameter and master cylinder pressure reduced braking distance and braking time. The best combination was obtained at a 260 mm disc brake diameter and 6 bar master cylinder pressure, producing a braking distance of 12.8 m and a braking time of 2.3 s.

Gangguan motorik halus pada anak usia prasekolah masih cukup tinggi, sehingga pada stimulasi untuk melatih kemampuan motorik halus anak, dalam melalui permainan edukatif seperti permainan kolase. Mengetahui pengaruh permainan kolase tematik terhadap kemampuan motorik halus anak usia prasekolah di TK Islam Gita Nanda Kecamatan Lowokwaru Kota Malang. Penelitian ini menggunakan desain quasi experimental dengan rancangan two group pretest-posttest design. Sampel penelitian berjumlah 41 responden yang terdiri dari kelompok kontrol sebanyak 21 anak dan kelompok intervensi sebanyak 20 anak. Intervensi permainan kolase tematik dilakukan selama 25 menit sebanyak 6 kali pertemuan. Pengumpulan data menggunakan lembar observasi kemampuan motorik halus. Analisis data menggunakan uji Wilcoxon dan uji Mann Whitney dengan taraf signifikansi ? = 0,05. Sebelum intervensi, seluruh responden (100%) pada kelompok intervensi berada pada kategori Belum Berkembang (BB). Setelah diberikan intervensi permainan kolase tematik, kemampuan motorik halus meningkat menjadi kategori Berkembang Sangat Baik (BSB) pada seluruh responden (100%). Hasil uji statistik menunjukkan nilai p-value = 0,000 (<0,05), sedangkan pada kelompok kontrol tidak terdapat perubahan yang signifikan dengan nilai p-value = 0,157 (>0,05). Permainan kolase tematik berpengaruh signifikan terhadap peningkatan kemampuan motorik halus anak usia prasekolah di TK Islam Gita Nanda Kecamatan Lowokwaru Kota Malang. Permainan kolase tematik dapat digunakan sebagai salah satu metode stimulasi perkembangan motorik halus pada anak usia prasekolah.

The road project serving as access to Lambo Dam in Rendubutowe Village, South Aesesa District, Nagekeo Regency, East Nusa Tenggara, uses various types of heavy equipment. The analysis method was carried out by recalculating productivity based on field data and references. Productivity calculations were related to the work volume in order to obtain daily productivity and the required duration. Therefore, theoretical calculation knowledge derived from previous studies was needed. Heavy equipment productivity was then analyzed to determine time efficiency. The subgrade work and pavement layer work on the road project to Lambo Dam, located in Rendubutowe Village, South Aesesa District, Nagekeo Regency, East Nusa Tenggara, had a road length of 6.3 km and a road width of 6 m. However, the observation was limited to a 1 km section from Station (Sta) 0+500 to Sta 1+500. The results obtained were productivity and duration for excavation work using an excavator and dump truck, each at 1785.6 m³/day in 4.52 days. Embankment work using an excavator and dump truck each had a productivity of 892.8 m³/day for 3.82 days, a bulldozer of 43,200 m³/day in 0.07 days, and a Vibro Roller of 168 m³/day in 20.27 days. Base course work used an excavator and dump truck with a productivity of 892.8 m³/day in 2.02 days, a motor grader of 23,372.8 m2/day, and a Vibro Roller of 168 m³/day for 10.71 days. Surface course work used a concrete Mixer truck with a productivity of 43.4 m³/day for 36.72 days. Heavy equipment productivity is influenced by the number of units used; the insufficient use of excavators causes dump truck productivity to be less than optimal in transporting excavation and embankment materials. Likewise, Vibro Rollers are needed in more than one unit so that the project can be completed faster

Bell’s palsy merupakan kelumpuhan perifer nervus fasialis (N VII) yang bersifat akut dan umumnya idiopatik. Penelitian ini bertujuan untuk  melaporkan kasus tentang gambaran klinis dan tata laksana Bell’s palsy perifer sinistra pada pasien anak usia 3 tahun. Jenis penelitian ini penelitian studi kasus melaporkan kasus Pasien datang dengan keluhan wajah asimetris sejak dua hari sebelum pemeriksaan, ditandai dengan sudut mulut kiri menurun, kesulitan menutup mata kiri (lagoftalmus), serta gangguan saat makan dan minum. Tidak ditemukan riwayat trauma, infeksi sistemik, maupun kelainan neurologis lain. Pemeriksaan fisik menunjukkan kondisi umum baik dengan tanda vital dalam batas normal. Status neurologis menunjukkan parese nervus fasialis sinistra tipe lower motor neuron, ditandai ketidakmampuan mengerutkan dahi kiri, lipatan nasolabial menghilang, dan senyum asimetris, tanpa keterlibatan saraf kranialis lainnya. Diagnosis ditegakkan sebagai Bell’s palsy perifer sinistra dengan diagnosis banding stroke iskemik dan sindrom Ramsay Hunt. Penatalaksanaan meliputi pemberian kortikosteroid (prednison), vitamin B kompleks, serta edukasi latihan otot wajah. Evaluasi lanjutan menunjukkan perbaikan bertahap dan pasien sembuh total dalam 14 hari tanpa komplikasi. Kasus ini menegaskan pentingnya diagnosis dini dan terapi adekuat pada Bell’s palsy anak untuk mencegah komplikasi dan mempercepat pemulihan fungsi saraf fasialis.

Transportation plays an important role in supporting community mobility and enhancing socio-economic activities in urban areas. The increasing population growth and community activities in Sorong City have led to a higher demand for transportation modes. This study aims to identify the characteristics of transportation users in Kota Sorong and to analyze the probability of selecting different transportation modes using the Multinomial Logit (MNL) method. A quantitative approach was employed in this research. Questionnaires were distributed to 225 transportation users in Sorong City. The variables analyzed included gender, age, occupation, income, trip purpose, travel frequency, and reasons for choosing a transportation mode. The data were analyzed using multinomial logistic regression with SPSS software. The results indicate that transportation mode choice is influenced not only by socio-economic factors, but also by showed that income, trip purpose, travel frequency, and reasons for choosing the mode significantly influenced transportation mode choice, while gender, age, and occupation did not have significant effects. The probability analysis indicated that private vehicles had the highest probability of selection at 89.63%, followed by online transportation at 9.96%, and conventional motorcycle taxis at 0.41%. These findings imply that socio-economic and travel behavior factors strongly influence transportation mode preferences in Sorong City and may serve as a reference for future urban transportation planning and policy development.

Motor Vehicle Tax (PKB) is a key pillar of Regional Original Revenue (PAD) that supports development funding. However, seasonal fluctuations in payment realization create uncertainties in local budget planning. This study aims to address the limitations of the standard Random Forestalgorithm, which suffers from extreme prediction failures on time-series data due to its inability to capture temporal transitions between months. The proposed solution implements feature engineering using a Cyclical Encoding approach (Sine and Cosine transformations) and Lagged Variables. The dataset comprises historical records of motor vehicle tax potential and realization from January 2021 to November 2025. The baseline model evaluation without feature engineering yields highly inaccurate predictions with a Mean Absolute Percentage Error (MAPE) of 203.47% (accuracy of -103.47%). Conversely, after integrating Cyclical Encoding and Lagged Variables, the proposed model's performance improves drastically, achieving a MAPE of 14.40% (an accuracy rate of 85.60%), an MAE of 9,317 units, and an RMSE of 12,638 units. Feature Importance analysis confirms that the cyclically encoded month feature contributes the highest weight to the model's decisions with a score of 0.5031, followed by the potential feature at 0.1798. This study demonstrates that time-based feature engineering effectively optimizes Random Forestfor precise tax revenue forecasting.

Dredger operations in water-based mining areas have a high occupational risk because they involve a combination of wet environments, mechanical equipment, and electrical systems. The presence of electrical panels, power cables, terminal connections, electric motors, inverters/drives, and protection components on the Dredger requires a sound understanding of Occupational Health and Safety, particularly electrical safety. Water splashes, wet walking surfaces, high humidity, and improper procedures during inspection or cleaning may increase the risk of short circuits, protection trips, and electric shock. Therefore, structured basic safety training is required so that operators are able to identify electrical hazards and implement safe working procedures. This activity aimed to improve operators’ understanding of hazardous electrical components, initial safety briefing procedures, measurement practice and safe handling during trips or short-circuit indications, and the correct and safe use of water pumps for unit cleaning. The activity was carried out through field observation, technical briefing, direct demonstration on the electrical panel and work area, simple measurement practice, and safe cleaning practice. The results indicate that field documentation can serve as an effective learning medium to strengthen operators’ understanding of electrical hazard sources on the Dredger, the application of simple lock out-tag out procedures, the control of wet areas, and the limitation of water spray direction during cleaning activities. Overall, the activity shows that improved compliance with safety procedures may reduce the risk of short circuits and electric shock during operation and maintenance.

Coal hauling activities are an important part of mining operation because they affect production continuity, cycle time efficiency, and operational safety. This study aims to analyze the requirements of road support equipment on the coal hauling road from Sector 4 to the new Coal Processing Plant (CPP) at PT. Asmin Bara Bronang, Central Kalimantan. Based on road geometry, traffic density, California Bearing Ratio (CBR), and Unsurfaced Road Condition Index (URCI). The research method used was applied research with a quantitative approach. Primary data ware collected through field measurements consisting of road geometri observations, traffic density observations, Dynamic Cone Penetrometer (DCP) testing to obtain CBR values, and road surface condition assessment using the URCI method. Secondary data were obtained from the company records. The results showed that the hauling road has a total length of 9.1 km with an average width of 16 m, and grade values ranging from -7.68% to 10.52%, which are still below the maximum standard of 12%. Traffic density reached 184 dump trucks/day, for coal hauling and 62 units/day for construction material transportation, indicating high traffic intensity. CBR values ranged from 7% to 100%, showing variations in subgrade bearing capacity. The URCI value ranged from 72,50 to 91.00, indicating fair to good road conditions. Based on the analysis of road conditions and maintenance area requirements, the recommended support equipment for maintaining the hauling road consists of 1 motor grader unit, 1 compactor unit, 1 bulldozer unit, and 1 water truck unit.

Along with the times, computer technology is developing very rapidly. The increasingly rapid development of computer technology means that everyone is required to utilize computer technology in their daily lives. Utilization of technology is one of the implementation roles of scientific disciplines. The reason behind the formation of this research is so that in the future it will become a fun learning concept in the introduction of objects and shapes in children and the motor development of children. children are usually more interested in seeing pictorial text, or pictures that contain lots of color. The Viola Jones method itself was chosen as the research completion algorithm. The Viola Jones method is usually used as a method in research that discusses the detection of objects, faces and others. The Viola Jones method was chosen because it has a high level of accuracy that can reach 100% probability.

The urgency of this research lies in the increasing risk of flooding and air pollution in Makassar City due to rapid urbanisation and the uncontrolled growth of motorised vehicles. The purpose of this study is to analyse the potential of urban planning and sustainable mobility policies in reducing disaster risks and environmental impacts, and to formulate more adaptive and data-driven policy strategies. This study uses qualitative methods by collecting data through interviews, documentation, observation, and focus group discussions (FGDs). Key informants include the Environmental Agency, the Spatial Planning Agency, and the Makassar Regional Disaster Management Agency (BPBD), which have strategic roles in spatial planning policies, environmental management, and disaster mitigation. The study findings indicate that flood risk and air pollution in Makassar City are complex problems influenced by population growth, land conversion, vehicle density, limited drainage, climate change, and industrial waste. Although various urban planning policies have been implemented, their effectiveness remains limited due to implementation constraints. Therefore, an integrated approach that combines adaptive urban planning, environmentally friendly mobility, effective waste management, and community participation is needed. With a systemic and coordinated strategy, Makassar has the potential to reduce flood risk, reduce pollution, and create a safer, healthier, and more sustainable urban environment.

This study aimed to examine the effect of location and promotion on consumer purchase decisions at the Kekang Motorcycle Showroom in Nangalimang, Maumere. The independent variables in this study were location (X1) and promotion (X2), while the dependent variable was the purchasing decision (Y). This study employed a quantitative research method. The sample consisted of 75 respondents, selected using an accidental sampling technique. Data were collected through observation, questionnaires, and documentation. The data analysis techniques included validity testing, reliability testing, classical assumption testing, multiple linear regression analysis, t-test, F-test, and coefficient of determination (R²). The results indicated that location had a positive and significant effect on purchase decisions at the Kekang Motorcycle Showroom in Nangalimang, Maumere. Meanwhile, promotion did not have a significant effect on purchase decisions. Simultaneously, location and promotion had a significant effect on purchase decisions. Thus, consumer purchase decisions were more strongly influenced by location than by promotion. Keywords: Location, Promotion, Consumer Purchase Decision.

The development of fine motor skills and collaborative character is an essential foundation during the golden age period to support children’s academic readiness and social development. However, learning stimulation at Tamalate State Kindergarten is still largely dominated by conventional methods that lack variety and interactive activities. This community service program aims to implement constructive Straw Connectorsmedia as an innovative learning solution to stimulate children’s fine motor skills and cooperative character. The implementation methods included teacher workshops, classroom application with students through collaborative constructive play activities, and evaluation of learning achievements. The findings revealed a significant improvement in children’s fine motor skills, with the average score increasing from 1.67 in the Pre-Test to 3.27 in the Post-Test. Furthermore, 60% of the children achieved the Very Well Developed (BSB) category in collaborative character development. Through the use of Straw Connectorsmedia, students were able to create complex architectural products such as construction bridges and windmills. The study concludes that Straw Connectorsmedia is effective in improving visual-motor coordination, creativity, and collaborative skills while fostering social empathy through interdependent interaction among children during the learning process.