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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.

Chronic Obstructive Pulmonary Disease is a chronic respiratory disease characterized by progressive and not fully reversible airflow limitation. Dyspnea is the primary symptom experienced by COPD patients and significantly affects their quality of life, especially among those hospitalized. This condition may lead to activity limitation, psychological distress, and decreased social functioning. This study aimed to determine the relationship between the level of dyspnea and the quality of life of COPD patients in the pulmonary inpatient ward of Cut Nyak Dhien General Hospital Meulaboh. This study employed an analytical design with a cross-sectional approach. The sample consisted of hospitalized COPD patients selected using purposive sampling. Dyspnea severity was measured using the Modified Medical Research Council (mMRC) scale, while quality of life was assessed using the St. George’s Respiratory Questionnaire (SGRQ). Data were analyzed using the Spearman correlation test to determine the relationship between variables.The results showed that most respondents experienced moderate to severe dyspnea and had poor quality of life. Statistical analysis revealed a significant relationship between dyspnea level and quality of life (p < 0.05) with a negative correlation.In conclusion, there is a significant relationship between dyspnea severity and quality of life in COPD patients, where higher dyspnea levels are associated with lower quality of life.

Asthma is a heterogeneous disease characterized by chronic inflammation of the airways and respiratory symptoms such as wheezing, shortness of breath, chest tightness, and cough, which vary over time in both frequency and severity. This condition is accompanied by limitations in expiratory airflow, which can be either reversible or persistent. In asthma patients, especially those treated in the Emergency Department (ED), a common nursing problem is ineffective airway clearance due to mucus accumulation and bronchospasm. One strategy to address this is the administration of warm drinking water, aimed at improving airway clearance. The design used in this final nursing scientific paper is a qualitative case study with an intervention of warm water intake. The subjects of this study consisted of 3 asthma patients in the ED, and the intervention was conducted from January 3-11, 2026, at the Emergency Department of Charitas Hospital Km.7 Palembang. Airway clearance was measured before and after the intervention, which involved giving 200 ml of warm water at 38ºC, without a control group. After the intervention, all three patients showed improved airway clearance, indicated by more effective coughing, decreased sputum production, reduced wheezing, improved breathing patterns, and improved respiratory rate. The implementation of this evidence-based practice (EBP) is expected to provide additional information regarding the use of nonpharmacological therapy, specifically the administration of warm drinking water, in asthma patients with ineffective airway clearance.

The purpose of this study is to develop an additional device for vehicles with fuel injection systems to improve fuel consumption efficiency and reduce exhaust emissions, even for older vehicles. The turbocyclone is an auxiliary component installed in the air intake duct before the throttle body to create a swirling airflow entering the combustion chamber. Testing was conducted at engine speeds ranging from 1500 rpm to 6500 rpm, with increments of 1000 rpm. This research aims to minimize fuel consumption and exhaust gas emissions. The experimental method was used, testing exhaust gas contents such as HC, CO, CO₂, and O₂ using a gas analyzer, and measuring fuel consumption based on fuel volume and time. Data processing employed a factorial DOE (Design of Experiments) to analyze results. The dependent variables were exhaust gas emissions and fuel consumption, while the independent variable was the turbocyclone blade angle variations of 20°, 40°, and 60°. The results show that the best reduction in exhaust emissions (HC, CO, CO₂, and O₂) and fuel efficiency occurred at a 40° blade angle, whereas fuel consumption increased at a 60° blade angle.

This design project is motivated by the low public interest in sports and the limited availability of sports facilities, creating a need for a sports hall that is both effective and efficient in enhancing the community’s quality of life. However, the mere provision of a sports facility is not sufficient; considerations such as building orientation, opening design, and airflow circulation are essential to create an optimal environment for sports activities. Therefore, the tropical architecture approach serves as the primary design basis for the sports hall in Asahan Regency. The aim of this design is to support a healthy lifestyle and improve the quality of life of the local community through comfortable and safe sports activities. The design method adopts a qualitative approach, with data collected through interviews and field observations to understand the needs and preferences of the community. The design also reflects local identity through a mass transformation inspired by the shell form, symbolizing the city of Asahan. The shell structure system is known for its slenderness, making it lightweight and efficient, while its curvature ensures even load distribution. This approach can serve as a model for future sports facility developments in Asahan Regency. This sports hall is expected to become a central hub for athletes in Asahan, providing optimal training facilities to improve their performance. With a modern building and complete facilities, the community can engage in sports activities more comfortably and safely, thus increasing public interest in sports and enhancing overall well-being. This design also aims to promote awareness of the importance of a healthy lifestyle through an effective and efficient sports center.

This community service activity aims to provide education and technical recommendations related to energy efficiency and thermal comfort in the BIN Apartment building through simulations using DesignBuilder software. The purpose of the activity is to analyze and optimize the building’s energy consumption and ensure thermal comfort for the residents. The simulation results show that the building's Energy Use Intensity (EUI) is relatively low for the residential category, based on calculations made by the BGH team. The air conditioning (AC) system in conditioned spaces meets the thermal comfort standards according to ASHRAE, ensuring comfortable living conditions in these areas. However, in unconditioned areas, such as the family room, the Predicted Mean Vote (PMV) value reaches 1.5 (hot), indicating thermal discomfort. To address this issue, mechanical ventilation is recommended, with the capacity to produce an average air velocity of at least 0.6 m/s, which will improve airflow and enhance thermal comfort. Alternatively, adding an additional AC unit can also be considered, though it would result in a 20% increase in energy consumption. The findings and recommendations of this activity are expected to provide valuable insights and assist partners in making informed technical decisions when designing efficient and comfortable HVAC systems for vertical state-owned residential buildings. Ultimately, this program aims to optimize both energy usage and comfort, contributing to sustainable building management practices in the future.

Air circulation and natural lighting are among the key aspects influencing the comfort of room usage, particularly in dormitory buildings inhabited by university students. This study aims to explore thermal comfort more deeply, focusing on air circulation and natural lighting within student dormitory rooms in the Riau Islands. A qualitative method was employed, collecting up-to-date data on the selected building. Building simulations using Computational Fluid Dynamics (CFD) and DIALux were conducted to analyze the speed of air circulation and the quality of natural lighting within the rooms. The results reveal that prior to evaluation, the dormitory rooms faced thermal issues related to poor air circulation and insufficient natural lighting. Wind speed was recorded at less than 2 m/s, and the incoming and outgoing airflow collided due to the presence of only one ventilation access. The evaluation using cross-ventilation through room openings showed a positive impact on indoor air circulation, increasing wind speeds to 2–4 m/s. The cross-ventilation concept also enhanced the discharge and exchange of indoor air, preventing air stagnation. In terms of natural lighting, the simulation showed that lighting intensity in several rooms was below the minimum standard of 250 lux, particularly in areas far from the window openings. After modifications to the window layout and the addition of secondary light-transmitting elements, the lighting level significantly improved to meet the recommended standard. These findings highlight the importance of incorporating both passive ventilation and natural lighting strategies in student dormitory designs. Improving these environmental aspects not only enhances thermal comfort but also supports the health, productivity, and well-being of the residents. This study contributes to the growing body of research on sustainable dormitory design and can be used as a reference for future architectural planning and policy improvements.

The design of Lecturer Housing for Campus 4 Gorontalo State University is a strategic necessity in line with the expansion of educational institutions and the increasing number of educators requiring adequate and proximate housing. The primary objective of this research is to produce a lecturer housing design that is not only adaptive and sustainable, but also harmonized with the Regional Spatial Plan (RTRW) of Bone Bolango Regency. The research methodology encompasses a comprehensive site analysis, examining aspects such as climate conditions, topography, vegetation patterns, infrastructure and utility networks, ambient noise levels, and site accessibility. Furthermore, a zoning and spatial relationship study was conducted to determine effective space allocation based on the principles of tropical architecture and green building practices. The findings of the study highlight that a north-south building orientation significantly reduces heat absorption, while the integration of cross-ventilation strategies enhances natural airflow and thermal comfort. Spatial zoning into public, semi-public, private, and service areas allows for organized layouts and promotes social interaction among residents. Sustainability is reinforced through the application of green architectural technologies, including the use of green concrete, lightweight steel frameworks, solar energy panels, as well as integrated waste-water management systems that separate black water and grey water. Landscaping elements, both softscape and hardscape, are utilized to enhance aesthetics while supporting ecological balance and rainwater absorption. This design proposal contributes to the broader discourse of sustainable tropical housing and may serve as a replicable model for future lecturer housing projects in similar regional contexts. It emphasizes the importance of environmentally responsive, cost-efficient, and socially supportive residential architecture.

Internal combustion engines generate thermal energy through the combustion of an air-fuel mixture. The incoming air must be filtered, as it contains impurities and particles. While air filters are commonly made from paper, they can also be developed using organic waste materials such as sugarcane bagasse and rice husk. This study aims to analyze the effect of biocomposite air filters on engine power, torque, and specific fuel consumption (SFC), by varying the material composition and the number of pleats, and comparing the results with those of a standard air filter. The method used is a quantitative experimental approach involving dyno testing on a 150 cc motorcycle engine. The tested material compositions include 50:50, 40:60, 30:70, 60:40, and 70:30 (sugarcane bagasse\:rice husk), with pleat counts of 28, 26, and 24. Results showed that the biocomposite filter with 28 pleats and a 30:70 composition delivered the best performance, producing 18.47 Hp and 16.66 Nm of torque—higher than the standard filter’s 17.98 Hp and 15.52 Nm. In terms of fuel efficiency, the 26-pleat filter with a 50:50 composition recorded the lowest SFC at 41.90 g/kWh, significantly better than the standard filter’s 53.03 g/kWh. Conversely, the 60:40 composition resulted in the highest SFC due to increased airflow resistance.

Introduction: Chronic Obstructive Pulmonary Disease or often referred to as COPD, is a disease that occurs due to limited airflow, this is caused by abnormalities of the airways and/or damage to the alveoli, abnormalities or damage that occurs are caused by significant exposure to hazardous particles or gases, not only due to exposure, COPD is also influenced by lung abnormalities. Dyspnea is a condition that describes a sensation of shortness of breath, which is characterized by obstruction of airflow, or difficulty breathing and chest tightness which is often associated with heart or respiratory disease. Purpose: This study is to determine the management of physiotherapy in cases of right chronic obstructive pulmonary disease. Method: This study uses a case report approach in patients with right chronic obstructive pulmonary disease by providing interventions in the form of nebulizers, pulsed lip breathing and muscle release for 4 weeks 5x meetings with doses of 3 times a day every week. Evaluation is carried out using the vital sign index, auscultation, borg scale, MMRC scale and thorax cage mobilization examination. Results: evaluation measurements using vital sign index, auscultation, borg scale, MMRC scale and thorax cage examination. Thus, the results show an increase and decrease in the degree of shortness of breath before and after intervention. Conclusion: there is an increase and decrease in shortness of breath before and after intervention.

COPD is a condition characterized by airflow obstruction that cannot be completely corrected. This limitation generally worsens over time and is associated with abnormal permeability to noxious particles or gases, resulting in narrowing of the airways, increased mucus secretion, and changes in the vascular system. The increase in chest expansion capacity is caused by the activity of respiratory muscle contraction. The activity of the respiratory muscles plays a role in chest expansion, which also affects lung growth. It is stated that the strength of the respiratory muscles decreases with age. Loss of intercostal muscle mass and strength are factors that reduce the ability of chest wall presence or development. This study used a case report design research method. Physiotherapy management for COPD is increasingly focused on exercise-based rehabilitation, both in outpatient and inpatient settings. Some therapies such as breathing exercises, thoracic expansion exercises and muscle release.

The development of electric propulsion systems has become a major focus in efforts to provide energy-efficient and environmentally friendly air propulsion technology. One emerging innovation is the electric motor-based turbojet fan, which is expected to replace conventional fossil-fueled systems. As the need for energy efficiency increases, studies on electrical power consumption and airflow performance are crucial in supporting the development of new-generation propulsion systems. This study aims to evaluate the relationship between nozzle angle and the characteristics of electrical power consumption and airflow velocity in a double-spool turbojet fan. The method used is an experimental test with an ESP32-based control system. The duty cycle is set at 80% to maintain operational stability. Research data is obtained through measurements of electrical current, voltage, and airflow velocity. The nozzle angle variations tested include 13°, 19°, and 25°. The test results show a significant difference between nozzle angle variations on electrical power consumption and wind speed performance. The 13° nozzle angle produces the highest electrical power consumption, indicating a greater energy requirement to maintain airflow. Conversely, the optimal wind speed was found at an angle of 19°, indicating a balance between energy efficiency and aerodynamic performance. Meanwhile, an angle of 25° showed a decrease in performance in terms of both power and speed, making it less effective. In conclusion, the nozzle configuration has a direct influence on energy consumption and fluid dynamics in electric turbojet fan systems. This research provides an important contribution to the design of electric-based propulsion systems by emphasizing efficiency and performance aspects, while supporting the transition to environmentally friendly technologies.

The reliability of a data center is highly dependent on its air conditioning and cooling system. This research evaluates the existing cooling system of Universitas Krisnadwipayana’s data center using the PPDIOO Network Life-Cycle approach. The study finds that the current cooling system, which relies on AC Split, fails to meet TIA-942 standards, posing significant overheating risks and increasing downtime probability. Observational analysis shows that the cooling distribution is inefficient due to inadequate airflow and the absence of a structured cooling layout. To address these issues, this research proposes an optimized cooling system design that incorporates Computer Room Air Conditioning (CRAC), hot aisle-cold aisle arrangement, and raised floor implementation. The recommended improvements also include installing temperature and humidity sensors for real-time environmental monitoring and implementing N+1 redundancy for enhanced system reliability. These solutions are expected to improve cooling efficiency, reduce energy consumption, and mitigate downtime risks. Future research should focus on evaluating the practical impact of this design by conducting real-world trials and exploring liquid cooling technology as a potential alternative for further efficiency improvements.

Smoke hazards can result in poisoning of harmful gases produced by the welding process. So it is expected that in order to maintain air cleanliness in the welding workshop by installing an exhaust gas channel from welding, the purpose of this research is to analyse the flow of exhaust gas through simulation of fluid flow velocity (welding smoke) in the design of exhaust gas installation in the welding workshop using CFD or Computational Fluid Dynamics method. CFD simulation can predict in detail the movement of wind (moving fluid) in the welding fume exhaust duct. CFD simulation is carried out through three stages, namely pre-processing, solving, and post-processing. This CFD uses the Solidworks (Flow Simulation) application programme. It was found that the installation of a welding fume exhaust duct with an output capacity of 39 m³ per minute showed a significant increase in airflow velocity. The first simulation results at the exhaust fan (welding booth) showed a maximum velocity value of 13.14 m/s and an average velocity of 10.55 m/s, the Reynold's number was 84567.11. In the second simulation, with the axial fan (Fan stationary) at 2600 RPM and pipe diameter 127 mm, better results were obtained, namely minimum velocity of 12.88 m/s, average velocity 13.94 m/s, maximum velocity 14.53 m/s and Reynold's number 111512.74. So the simulation results show an improvement in the performance of the ventilation system, where the airflow velocity is quite good, which ensures the efficiency of the ventilation system.

Chronic Obstructive Pulmonary Disease (COPD) is a lung condition characterized by persistent and typically progressive respiratory symptoms and airflow limitation. This disease is associated with an excessive chronic inflammatory response in the airways and lung parenchyma due to exposure to harmful gases or particles. The objective of this study is to evaluate the changes in oxygen saturation and activity tolerance in COPD patients before and after performing home-based walking exercises, pursed lips breathing, and effective coughing. The research method used a descriptive design in the form of a case report with a nursing process approach. The instruments used included assessment sheets and oximetry to measure oxygen saturation. The study subjects were patients with COPD. The results showed that before the intervention, the patient's (Mrs. E) oxygen saturation was 96%, and she reported difficulty engaging in activities due to fatigue and shortness of breath. After three days of intervention, her oxygen saturation increased to 99%, and she was able to perform outdoor activities without experiencing shortness of breath. In conclusion, home-based walking exercises, pursed lips breathing, and effective coughing can improve oxygen saturation, increase activity tolerance, and reduce dyspnea and fatigue  

Asthma is a chronic disease characterized by airway hyperactivity due to inflammation and reversible airflow obstruction. The most common triggers of asthma are allergies (food or inhalants such as dander, dust, pollen), exposure to cold temperatures, and upper respiratory infections. Non-pharmacological therapy can be carried out with the buteyko breathing technique which aims to reduce dyspnea, asthma attacks, wheezing, reduce symptoms of nasal congestion and stop coughing experienced by sufferers. The purpose of this study was to determine the effectiveness of buteyko exercise on dyspnea symptoms in asthma sufferers. The research method used was a pre-experimental one group pretest-posttest to see differences in the dyspnea scale in the intervention group before and after the buteyko exercise. The results of the pre-test and post-test statistics p = 0.025 <0.05 where there were differences in the dyspnea scale after being given buteyko exercises. Prior to the Buteyko exercise, it was shown that 4 respondents (40%) had mild dyspnea, 4 respondents (40%) had mild, 2 respondents (20%) were mild. After doing the buteyko exercise, it was shown that 7 respondents (70%) had mild dyspnea, 3 respondents (30%) had mild symptoms. Research shows that there is a decrease in the level of dyspnea after being given buteyko exercises with an average dyspnea scale decreasing (negative rank) with a result of 3.00. It was concluded that there were differences in the dyspnea scale after being given buteyko exercises, that there were significant results for a decrease in the dyspnea scale in asthma sufferers.

The theory of consonants in English phonology is an important aspect in understanding the sound system in that language. Phonology is the study of how the sounds in language are used to form meaning. In English, consonants and vowels have different roles in forming word structure and sound articulation.Consonants in English are defined as sounds that experience resistance or airflow shift when spoken. There are various types of consonants in English, such as hissing consonants, popping consonants, sliding consonants, and so on. These consonants have certain characteristics, such as the place and manner of articulation, which distinguish one consonant from another.Places of articulation refer to the parts in the mouth or throat that are used to produce consonant sounds. For example, the lips, teeth, tongue, palate, and throat can play a role in the production of consonants. For example, the consonant /p/ is pronounced by bringing the lips together, while the consonant /k/ is pronounced by moving the back palate with the back of the tongue.The manner of articulation refers to the type of resistance or shift in airflow that occurs when pronouncing the consonant. Some examples of how consonants are articulated in English include complete closure of the airflow (eg /p/), partial obstruction of the airflow (eg /s/), or passage of air through the nose (eg /m/). The theory of consonants and vowels in English phonology helps to explain how these sounds form a distinctive language system. Knowledge of the place and manner of consonant articulation, as well as the position of the tongue and the tilt of the vowel lips, allows linguistics to analyze the differences in sounds in English. In the study of phonology, this theory also helps to understand sound patterns, sound changes, and the placement of sounds in words as well as in the broader structure of language.     

Background: Most respiratory disorders are caused by problems or diseases of the respiratory system, including the lungs. Inability of the lungs to expand (elasticity), as well as structural (anatomical) and functional airway obstructions that prevent the creation of breathable airflow, are signs of impaired lung function. Restriction and blockage are two types of lung function problems.Purpose: To analyze the application of the tripod position and pursed lip breathing technique to the increase in oxygen saturation in congested patients in the emergency room at PROF Hospital. Dr. SABOE TONGUE.Methods: Case report, which is a narrative report. The case study in this paper examines the use of a tripod position and pursed lip breathing technique to increase oxygen saturation in shortness of breath patients. Patients with asthma, lung cancer, TB, and COPD constitute the study population. Four patients with asthma, lung cancer, tuberculosis, and COPD were sampled for the study.Results: After the nurse's intervention was carried out, which was related to airway management in the fourth patient, the overall evaluation results were obtained, then the intervention was continued in the patient's treatment room.Conclusion: Based on the description above, people with respiratory problems often experience decreased functional daily activities, decreased concentration, and mood swings. As a result, if the condition of shortness of breath is allowed to continue unnoticed it will reduce oxygen saturation which in turn can cause cyanosis in patients who experience recurrent infections.  

Comfort can be provided from a building, inseparable from the existence of the building itself in the context of an environment that is limited by consideration of natural factors. In an effort to achieve comfort in buildings in tropical climates such as Indonesia, especially the city of Maumere, with characteristics of wind speed, humidity and relatively high air temperature and solar heat radiation can reach levels outside the human comfort zone. This study compares the speed and direction of wind flow in different lecture halls, seen from the level of height, direction and contour of the ground. The method used is data taken using equipment measured in the field and the results are simulated using WinAir4 from ECOTEC. The results obtained are the effect of altitude level, direction and contour orientation on wind speed and air flow in the design of the lecture hall in relation to thermal comfort.