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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.

Diesel engines are widely used in the transportation and industrial sectors due to their high thermal efficiency and good operational durability. However, increased fuel consumption due to inefficiency of the injection system remains a common problem. Injector characteristics, particularly nozzle diameter and injection pressure, are important factors that affect the quality of fuel atomization, air-fuel mixing, and combustion efficiency. An inappropriate combination of parameters can cause suboptimal combustion and increase fuel consumption. This study aims to analyze the effect of variations in nozzle diameter and injection pressure on fuel consumption efficiency in diesel engines. The method used is an experiment with variations in nozzle diameter of 0.150 mm, 0.152 mm, and 0.154 mm and injection pressures of 400 bar, 420 bar, and 440 bar. Tests were conducted at engine speeds of 500 rpm, 1000 rpm, and 1500 rpm with a fuel consumption measurement time of one minute for each parameter combination. Fuel consumption was measured using the volumetric method and analyzed through the fuel volumetric flow rate, fuel mass flow rate, Brake Power (BP), and Brake Specific Fuel Consumption (BSFC). The results showed that the combination of a nozzle diameter of 0.150 mm and an injection pressure of 400 bar produced the lowest BSFC value, thus providing the best fuel consumption efficiency. Meanwhile, the combination of a nozzle diameter of 0.152 mm and an injection pressure of 420 bar showed the closest condition to optimal because it was able to provide a balance between atomization quality and the amount of fuel injected, resulting in efficient and stable combustion. Thus, the efficiency of a diesel engine is influenced by the balance of nozzle size and injection pressure, not solely by the lowest fuel consumption.

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.

This study aims to analyze public concerns regarding fast food consumption from the perspective of risk society, particularly among university students. The increasing consumption of fast food reflects shifts in consumption patterns influenced by globalization, practicality, and time efficiency. This research employs a qualitative approach through a literature review supported by interview data to strengthen the analysis. The findings reveal that fast food consumption is not solely driven by biological needs but also by practical, emotional, and social factors. Although students demonstrate a relatively high awareness of health risks associated with fast food, their consumption behavior persists as an adaptive response to structural conditions such as time constraints, accessibility, and academic pressures. From the perspective of risk society, this phenomenon illustrates a contradiction between risk awareness and everyday consumption practices. Risks produced by modernity are not entirely avoided but are negotiated and normalized in daily life. Therefore, fast food consumption cannot be understood merely as an individual choice but as a result of the interaction between structural factors, consumer culture, and social construction within modern society.

According to the WHO and the Ministry of Health, hypertension is defined as blood pressure ≥ 140/90 mmHg, consistent with the ESC/ESH guidelines. Hypertension is one of the leading causes of premature death worldwide. Symptoms experienced by patients with hypertension include headaches, sweating, palpitations, snoring, daytime sleepiness, muscle weakness, cramps, and cardiac arrhythmia. Clinical manifestations of hypertensive urgency include elevated blood pressure, severe headache, anxiety, and shortness of breath. Mrs. M, a 68-year-old woman, came to the Samudera Community Health Center complaining of a headache that had worsened approximately 3 days ago. The headache is felt at the back of the head, feeling heavy, and sometimes radiates throughout the entire head. The patient also describes the headache as throbbing. The headache was exacerbated when the patient could not sleep, consumed salty foods, and did not take her medication regularly.  The headache subsides slightly when the patient takes medication and sleeps with their head elevated.  The patient reported that the symptoms were also accompanied by nausea, dizziness, palpitations, and an inability to sleep at night. The patient has been diagnosed with hypertension for approximately 5 years. On physical examination, the patient’s blood pressure was 190/100 mmHg. The patient was advised to adopt a healthy diet by reducing salt intake. The patient was also prescribed the following medications: Captopril 25 mg twice daily, Amlodipine 5 mg once daily, Paracetamol 500 mg three times daily, and Domperidone 10 mg twice daily, to be taken as needed.

Mental health issues among university students have become a growing concern, driven by academic pressures, career uncertainties, and complex social transitions. However, a large proportion of students remains reluctant to seek professional psychological support due to social stigma and limited access to institutional counseling services. This study proposes the design and implementation of an Android-based chatbot application that integrates mood tracking and sentiment analysis to continuously monitor the emotional states of university students. The system employs a fine-tuned RoBERTa (Robustly Optimized BERT Pretraining Approach) model trained on the EmoContext conversational dataset (SemEval-2019 Task 3), comprising 30,160 labeled three-turn dialogue instances across four emotion classes: angry, happy, sad, and others. The model was fine-tuned for four epochs using the AdamW optimizer with a learning rate of 2e-5 and a maximum sequence length of 128 tokens. Evaluation on a held-out validation set of 6,032 samples yielded an overall accuracy of 88.28%, a macro-average F1-score of 0.87, and a weighted-average F1-score of 0.88. Per-class F1-scores were 0.89 (angry), 0.83 (happy), 0.91 (others), and 0.86 (sad). The classified emotion is transmitted in real time to the chatbot response logic, which generates empathetic replies and personalized relaxation recommendations based on the detected mood. Primary data collection through questionnaires and interviews with 62 and 19 university students respectively confirmed the need for accessible digital mental health support. The results demonstrate that RoBERTa-based fine-tuning on conversational data provides a reliable foundation for real-time emotion-aware mental health chatbot systems.

Social media has become a primary means of communication for adolescents in the digital era, yet excessive use can create complex impacts on their academic, social, and psychological well-being. The positive effects include expanding cross-regional friendships, improving communication skills, strengthening social relationships, and increasing learning motivation through peer interaction and support. Conversely, the negative effects include declining academic performance due to reduced focus, neglect of responsibilities, weakened language skills caused by the dominance of informal language, a higher risk of digital crimes such as fraud and identity theft, as well as mental-health issues including anxiety, depression, social-comparison pressure, and cyberbullying. To minimize these risks, preventive efforts are needed, such as enhancing digital literacy for both adolescents and parents, promoting ethical and safe online behavior, regulating screen time, strengthening parental guidance, implementing digital-wellness policies in schools, providing counseling services, developing more youth-friendly platforms, and enforcing government regulations on online safety. This study emphasizes that the wise, safe, and productive use of social media can only be achieved through collaborative efforts involving adolescents, families, schools, communities, platform providers, and the government.

This qualitative literature review explores how digital activism is transforming stakeholder influence and corporate responsiveness. Contrary to traditional models emphasizing unified collective action, recent evidence reveals that heterogeneous stakeholders now mobilize through fragmented yet emotionally resonant digital narratives. This form of "heterogeneous convergence" enables diverse publics to exert pressure on firms despite lacking organizational coherence. Drawing from contemporary cases such as #MeToo and #DeleteUber, the review highlights how digital platforms facilitate dynamic stakeholder engagement, enabling rapid reputational impacts. The findings suggest that organizations must adapt to increasingly polyphonic and contested stakeholder environments, where legitimacy is shaped not by static engagement models but by real-time digital responsiveness. This review contributes to stakeholder theory by integrating digital mobilization dynamics and calls for expanded theoretical and empirical research into digitally mediated stakeholder influence

This research is motivated by the importance tank cleaning process on tankers to prevent cargo contamination, maintain cargo quality, and ensure crew safety. MT. Marina Prosperity, a chemical/oil tanker, uses the Butterworth system as the primary method for tank cleaning at every cargo change. However, in practice, technical and operational constraints are still found that affect the results of tank cleaning. The research method used is descriptive qualitative with data collection techniques through direct observation on the ship, interviews with the Chief Officer and Boatswain, and documentation studies in the form of log books and SOPs. Data were analyzed by focusing on three aspects, namely work efficiency, work safety, and operational procedures for using Butterworth. The results show that the use of Butterworth can increase time and energy efficiency compared to manual methods, with an average cleaning time of 2–4 hours per tank depending on the type of cargo. From a safety aspect, Butterworth reduces the need for crew to enter the tank, thereby reducing the risk of exposure to chemicals and hazardous atmospheres. However, work effectiveness and safety are greatly influenced by the condition of the equipment, the stability of water pressure, and the crew's discipline in implementing the SOP. On several occasions, steps such as nozzle cleaning, manual mopping, and safety meetings were not consistently performed, resulting in residual load in certain areas. With routine equipment maintenance, close supervision, and ongoing crew training, Butterworth can be optimized to produce more effective, safe, and standards-compliant tank cleaning process.

This study aims to qualitatively analyze the impact of order cancellations and customer ratings on the performance, performance, and income of online motorcycle taxi (Gojek) drivers in the Slawi region. The research method used a qualitative approach with data collection techniques through in-depth interviews, observation, and documentation of a number of active drivers. The results show that the high rate of order cancellations, both from customers and the system, negatively impacts driver income stability and reduces work time efficiency. Furthermore, customer ratings play a crucial role in determining driver access to orders, incentives, and account sustainability. Drivers with low ratings tend to experience decreased performance due to limited opportunities to receive orders. On the other hand, the pressure to maintain high ratings also affects drivers' psychological state and work strategies. This study concludes that order cancellations and customer ratings are crucial factors that are interrelated in influencing the work quality and welfare of online motorcycle taxi drivers. Therefore, fairer and more transparent platform policies are needed to maintain a balance between customer satisfaction and driver protection.

This reflective autoethnographic study explores the lived experience of being an only child caring for an elderly mother with Parkinson's disease while working as a full-time lecturer. The research aims to understand how this dual role affects the caregiver's mental health, work productivity, and relationship with the mother. Using a reflective autoethnographic approach based on Ellis, data were collected through three techniques: autobiographical narratives and memos, analysis of personal artifacts (work schedules, medical records, photographs), and an integrated self-interview. Thematic-reflective analysis revealed three main themes. First, structural loneliness describes the profound isolation resulting from having no sibling to share physical, emotional, and decisional responsibilities, which informal support cannot easily remedy. Second, stealth strategies at work refer to hidden tactics such as leaving early without disclosure, using breaks to check on the mother, and concealing caregiving struggles to avoid being perceived as less committed or losing professional opportunities. Third, fought for bonds shows that despite exhaustion and initial frustration, the caregiver’s relationship with her mother deepened through daily effort, patience, and reframing caregiving as meaningful devotion, a process aligned with filial maturity. The findings highlight the unique pressures faced by only-child working caregivers, including invisible productivity loss and the inadequacy of general social support. Practical implications for employers, social workers, and policymakers are discussed. This study contributes a rich first-person account to the underexplored area of only-child caregiving and offers recommendations for workplace cultural change, targeted support groups, and subsidized respite services.

Academic stress is one of the common problems students face due to various learning demands, such as piling up assignments, pressure to achieve, and difficulty managing study time. This study aims to describe the concept of handling academic stress in students at SMA Negeri 1 Panyabungan through Islamic guidance and counseling. The research uses a qualitative descriptive approach with data collection techniques in the form of interviews with teachers involved in guidance and counseling services at the school. The results of the study show that academic stress in students is marked by decreased concentration in studying, frequent lateness, not completing assignments, and a lack of motivation to study. The dominant contributing factors are lack of rest, academic pressure, and suboptimal self-management skills. Handling this is done through giving Islamic advice, study motivation, religious coaching, as well as guidance from both guidance counselors and teachers. The handling is done through giving Islamic advice, study motivation, religious guidance, and support from school counselors and religious teachers. The Islamic guidance and counseling approach is considered able to help students gain peace, increase study motivation, and form more positive behaviors in facing academic demands.

The tradition of marriage gift money (uang hantaran) in the Malay community of Melibur Village, Talang Muandau District, Bengkalis Regency, Riau Province, remains a customary practice preserved as a symbol of respect for the bride’s family and a sign of the groom’s seriousness. However, over time, its meaning has shifted toward materialism, as the amount is often determined by social status, educational background, and family prestige, potentially causing economic burdens, psychological pressure, delays, and even the cancellation of marriages. This study aims to describe the practice of uang hantaran and formulate an Islamic legal reconstruction of the tradition in accordance with the principle of simplicity. This research is a field research employing a qualitative approach. Data were collected through interviews, observations, and documentation, and were analyzed descriptively and analytically using the maslahahmursalah approach in Islamic law. The findings indicate that the practice of uang hantaran in Melibur Village is still maintained as part of local custom; however, its implementation has shifted from a symbolic function to a materialistic one, resulting in economic pressure on the groom’s family, psychological burdens on prospective spouses, and delays in marriage. From the perspective of maslahahmursalah, uang hantaran may be categorized as maslahahhajiyyah when determined flexibly and without imposing hardship, but it becomes mafsadah when the amount is excessive and causes harm. Therefore, the reconstruction of Islamic law regarding this tradition emphasizes that uang hantaran is not a legal requirement for marriage but rather a complementary customary practice whose determination should be based on deliberation, mutual consent, economic capability, and the principle of simplicity (taysir), so that it does not hinder the objectives of marriage in Islam.

The development of Artificial Intelligence (AI) integrated with biometric technology has opened new opportunities in leadership development, particularly in enhancing emotional regulation capabilities within high-stakes environments. This study aims to analyze the role of AI-driven biometric feedback in improving self-awareness, emotional regulation, and decision-making quality among leaders. The study employs a systematic literature review approach by examining recent reputable scientific publications related to AI, biometrics, and leadership. The findings indicate that physiological data such as heart rate variability (HRV) and galvanic skin response (GSR), when processed through AI systems, can provide real-time feedback that enhances individuals’ ability to recognize and regulate emotions adaptively. Furthermore, the integration of this technology contributes to improved accuracy and consistency in decision-making under pressure. The results also reveal that the effectiveness of implementation is influenced by both technical and non-technical factors, including data quality, algorithm accuracy, and user acceptance. This study contributes to strengthening the integration of psychological and technological approaches in modern leadership research and offers practical implications for developing data-driven leadership training programs in the digital era.

Preeclampsia remains a major contributor to maternal morbidity and mortality, particularly in developing countries such as Indonesia. Early detection and integrated management at the primary healthcare level are essential to prevent disease progression and improve maternal outcomes.  Modifiable risk factors such as maternal obesity, inadequate calcium intake, and poor clinical management contribute significantly to disease progression (WHO, 2021; Zhang et al., 2020). This study aimed to evaluate the effectiveness of an Integrated Maternal Health Model (IMHM) combining risk assessment, nutritional intervention, and clinical management for early prevention and control of preeclampsia in primary healthcare settings. A quasi-experimental cohort study was conducted among 104 pregnant women, consisting of 52 preeclamptic and 52 normotensive participants in community health centers in Medan, Indonesia. Data were collected across four antenatal visits, including blood pressure measurements, proteinuria (dipstick), calcium intake, supplementation adherence, and antihypertensive therapy. Statistical analyses included bivariate and longitudinal tests. The results showed that maternal obesity, history of preeclampsia, and hypertension were significant risk factors. Adequate calcium intake demonstrated a protective effect against preeclampsia (p < 0.05), consistent with recent evidence indicating that calcium supplementation can reduce the risk of preeclampsia by up to 49%. However, calcium supplementation did not significantly influence blood pressure among normotensive pregnant women. Antihypertensive therapy, particularly intensive nifedipine regimens, showed significant differences in blood pressure patterns across visits (p < 0.05). In addition, proteinuria levels significantly decreased over time (p < 0.001), indicating improvement in renal function. In conclusion, the IMHM is effective in improving maternal outcomes through a multi-component approach integrating clinical, nutritional, and monitoring strategies. This model provides a practical and scalable framework for early prevention and management of preeclampsia in primary healthcare settings.

This study aims to analyze people's online shopping behavior and assess its impact on family economic conditions. The development of digital technology has transformed people's consumption habits, particularly in shopping activities, which are now increasingly practical through online platforms. Easy access, product diversity, and various payment options have made online shopping a dominant trend. However, this convenience also has the potential to foster consumer behavior that impacts financial stability. This study aims to analyze bold shopping patterns and their impact on household financial conditions. The approach used is descriptive qualitative library research, collecting and analyzing data from various scientific journals, articles, and related references. The study findings indicate that online shopping has diverse effects: on the one hand, it offers time and cost savings, but on the other hand, it can lead to waste and indiscipline in family budget management if not supported by adequate self-control. Therefore, an understanding of financial management and digital literacy is crucial to ensure optimal use of technology without harming family economic well-being. Furthermore, this phenomenon requires synergy between digital platform policies and consumer education to mitigate the risk of impulsive buying. This research confirms that psychological factors often outweigh objective needs in digital transactions. As a recommendation, adaptive financial management support strategies are needed for families in this era of disruption to maintain domestic economic resilience against the pressures of a modern lifestyle.

The rapid growth of digital marketplaces has significantly reshaped consumption behavior among university students. Promotional strategies based on scarcity and urgency, such as flash sales, limited-time discounts, and countdown timers, are designed to induce psychological pressure, potentially triggering Fear of Missing Out (FoMO). This study aims to examine the relationship between self-control and FoMO among university students who use digital marketplaces. A quantitative correlational design was employed, involving 70 undergraduate students selected through accidental sampling. Self-control was measured using the Brief Self-Control Scale, while FoMO was assessed using an adapted Online FoMO Scale. Data were analyzed using Pearson’s product-moment correlation after fulfilling normality assumptions. The results revealed a significant negative relationship between self-control and FoMO (r = –0.522, p < .001), indicating that individuals with higher self-control tend to experience lower levels of FoMO in marketplace contexts. These findings highlight the role of self-regulation as a protective factor against emotionally driven consumption behavior. This study contributes to the literature on digital consumer psychology by extending the concept of FoMO beyond social interaction into economic decision-making contexts. Strengthening self-control is therefore essential in helping individuals manage psychological pressure arising from urgency-based marketing strategies.

This literature study examines the process of self-regulation in transforming compliance with school rules originating from external pressure into behavioral regularity emerging from personal awareness, and its impact on the effectiveness of student learning outcomes. Using a qualitative approach with content analysis method, this study synthesizes relevant literature to build a theoretical framework on how self-regulation facilitates the internalization of disciplinary values. The findings reveal that self-regulation occurs through a series of interconnected stages including goal setting, strategy planning, self-monitoring, evaluation, and adjustment. The success of this process is determined by internal motivation, appropriate environmental support, positive direct experiences, and healthy emotional management. Strong self-regulation directly impacts learning outcome effectiveness through improved cognitive strategies, strengthened intrinsic motivation, enhanced time and environment management, and developed capacity to constructively cope with failure. Learning outcomes achieved through self-regulation processes are characterized by lasting understanding, knowledge transfer ability, and the formation of lifelong learning dispositions. Schools and teachers play strategic roles in strengthening self-regulation through curriculum design that supports autonomy, formative feedback, role modeling, and collaboration with parents. This study contributes theoretically by positioning self-regulation as the central mechanism bridging external influences and internal disposition formation.

The steering gear is a vital component in ship operations, functioning to control the ship’s direction accurately. The reliability of this system highly depends on the performance of the hydraulic system, where the mechanical seal plays a key role in maintaining system pressure and preventing oil leakage. This study aims to identify the main factors causing mechanical seal damage and analyze its impact on the performance efficiency of the steering gear AHTS Logindo Stamina. Qualitative data were obtained through participatory observation and in-depth interviews with the second engineer. Meanwhile, quantitative data were gathered by measuring technical parameters such as oil pressure, operating temperature, and rudder movement time, which were then compared with SOLAS standards. This damage results in oil leakage through the mechanical seal gap, abnormal noise in the hydraulic system, and a significant decrease in working pressure of -25,86%. The operational impacts include the occurrence of steering gear failure alarms, decreased hydraulic efficiency of 25.87%, and the risk of system failure that could endanger ship maneuverability. This study recommends preventive maintenance through oil quality monitoring, environmental condition control in the steering gear room, and periodic mechanical seal replacement in accordance with operational standards to maintaining optimal steering system performance.

The postpartum period is an important time for the mother's physiological recovery after childbirth, during which various bodily changes are still ongoing and health risks, including changes in blood pressure, may occur. One factor that is thought to affect blood pressure during the postpartum period is dietary patterns, particularly high sodium intake. Salted fish is a food commonly consumed by the community and is known to have a high salt content. This study aims to analyze the effect of salted fish consumption on blood pressure in postpartum mothers from day 1 to day 28. This study used a quantitative approach with an analytical observational design through a cross-sectional method. The study sample consisted of 20 postpartum mothers on days 1–28 who were selected using purposive sampling. The independent variable was salted fish consumption, while the dependent variable was the systolic blood pressure of postpartum mothers. Data were collected through interviews using a structured questionnaire and blood pressure measurements with a standard tensiometer. Data analysis was performed using univariate and bivariate methods. The Shapiro–Wilk normality test showed that the data were not normally distributed, so the analysis was continued with the Wilcoxon test. The results of the study show a significant difference between systolic blood pressure before and after exposure to salted fish consumption, indicating that consumption of foods high in salt affects changes in blood pressure in postpartum women. This study concludes that salted fish consumption has the potential to affect the blood pressure of postpartum women. Therefore, nutrition education related to limiting the intake of foods high in salt during the postpartum period needs to be improved as part of efforts to prevent postpartum hypertension.