• Environmental Engineering Research
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• v.21 no.2
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• pp.145-151
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• 2016

Biodrying is a pre-treatment method that applies biological and mechanical concepts to drying solid waste. In Malaysia, municipal solid waste (MSW) is unseparated and contains a high level of moisture, making the use of technology such as solid waste burning unsuitable and harmful. MSW containing organic material can be processed naturally until the moisture content of the waste is reduced. This study on MSW biodrying was carried out on a laboratory scale to measure the percent moisture content reduction and to monitor temperature patterns under different ventilation periods. This work was conducted using five biodrying reactors volumes of 50 liters each. Reactors were ventilated for 5, 10, 15, 20 and 30 min every 3 h, with a 3 bar air supply. The duration of this process was 14 days for all samples. The results showed that the optimum ventilation time was 10 min, with an 81.84% reduction in moisture content, and that it required almost half of the electricity cost required for the 20 and 30 min ventilations.

• Journal of the Korean Society of Safety
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• v.36 no.1
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• pp.86-94
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• 2021

Lecture rooms are crowded with many attendees. Moreover, they rely significantly on the natural ventilation through windows for removing and controlling indoor contaminants such as CO₂. With the aim of broadening the understanding of the characteristics of natural ventilation phenomena in lecture rooms, the average individual CO₂ release rates of attendees were measured during the course of a lecture and compared with previously reported CO₂ release rates. In addition, the effects of natural ventilation through windows on the time-variant CO₂ concentrations in the center of the lecture room were measured and analyzed. Moreover, details about the overall and regional CO₂ concentrations, as well as the air flows in the lecture room, were simulated and analyzed with computational fluid dynamics software, Fluent 2020 R2. It was found that the average individual CO₂ release rates were slightly slower than previously reported rates. The local CO₂ concentrations in the lecture room for regions with a high density of attendees increased over a short period of time, although the natural ventilation was already started by opening the windows. The overall CO₂ concentration in the lecture room rapidly decreased in the early stage of ventilation, but declined very slowly after a longer period of ventilation time. Therefore, in order to enhance the efficiency of a lecture room's natural ventilation, it is recommended to homogeneously distribute the attendees in the lecture room, and to frequently open the windows for short periods of time.

• Journal of Chest Surgery
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• v.18 no.4
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• pp.771-779
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• 1985

It has been recognized that the proper matching of ventilation and perfusion within the lung is essential for the efficient exchange of gases following open heart surgery. Physiologic shunt reflects the amount of blood going to lung units with inadequate ventilation and these are also areas of the lung with adequate ventilation but inadequate blood flow. This can be quantified by measuring physiological dead space. From January to August 1985, The physiologic dead space and shunt during postoperative course had been taken in 30 patients of open heart surgery in Soonchunhyang University Hospital. Twenty cases had congenital heart disease and acquired valvular heart disease were noticed in 10 cases. The physiological dead space and shunt during postoperative periods were calculated and we made 5 items of conclusion: 1. There is high probability of ventilation-perfusion mismatch in the acquired heart disease group compared to the congenital group. 2. Duration of the CPB can exert significant influences in the physiological dead space but less in the shunt fraction. 3. There is positive relationship between Qs/Qt and Vd/Vt in the group B [CPB>90 min.] but less reliable in correlation. 4. Perfusion impairment is more significant in the diminished pulmonic blood flow group compared to the increased pulmonic blood flow [Qp/Qs>2.0] group. 5. There is no significant ventilation-perfusion mismatch within the lung during all postoperative courses.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.3
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• pp.58-67
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• 2006

In this paper, fuzzy logic based active ventilation system with security function is proposed and implemented. We can easily experience the situation that inner air is so hot to get start immediately after parking at summer day. Hot temperature is enough to explode a gas lighter or to suffocate a little chid. Proposed system has 1 blower and 2 axial fans to ventilate inner air. Based on the fuzzy logic, speed and direction of each fan are controlled. In addition to controlling fans, controller put down windows and adjust the periods of open time. In order to prevent the theft and security problems, IR sensors are used to detect objects. On detecting objects, controller put up windows. Experimental result shows that implemented system can be effectively ventilate inner air and reduce temperature. Proposed system can be applicable to commercial automobiles.

• Journal of Chest Surgery
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• v.55 no.4
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• pp.293-300
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• 2022

Lung transplantation is the only treatment option for patients with end-stage lung disease. Although more than 4,000 lung transplants are performed every year worldwide, the standardized protocols contain no guidelines for monitoring during lung transplantation. Specific anesthetic concerns are associated with lung transplantation, especially during critical periods, including anesthesia induction, the initiation of positive pressure ventilation, the establishment and maintenance of one-lung ventilation, pulmonary artery clamping, pulmonary artery unclamping, and reperfusion of the transplanted lung. Anesthetic management according to the special risks associated with a patient's existing lung disease and surgical stage is the most important factor. Successful anesthesia in lung transplantation can improve hemodynamic stability, oxygenation, ventilation, and outcomes. Therefore, anesthesiologists must have expertise in transesophageal echocardiography, extracorporeal life support, and cardiopulmonary anesthesia and understand the pathophysiology of end-stage lung disease and the drugs administered. In addition, communication among anesthesiologists, surgeons, and perfusionists during surgery is important to achieve optimal patient results.

• Proceedings of the SAREK Conference
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• 2005.06a
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• pp.145-145
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• 2005

• Fashion & Textile Research Journal
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• v.16 no.3
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• pp.485-491
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• 2014

This study verified the effect of summer flight ventilation developed in a previous study based on wearing comfort evaluation. Seven healthy males in their twenties volunteered for this experiment conducted in aclimatic chamber. The experiment consisted of three consecutive periods of rest (20 minutes), running on a treadmill (10 minutes) and recovery (20 minutes). A comparative evaluation was conducted on the general flight suit which had no ventilation holes and summer flight suit that use subjective satisfaction measures and objective measures. The subjective satisfaction was evaluated according to the criteria of temperature sensation, wet sensation, thermal comfort and fatigue sensation. The objective satisfaction was measured by skin temperature, microclimate (temperature and humidity), sweat rate and thermography. The comparative wearing evaluation identified the summer flight suit decreased the temperature between skin and suit by $0.42^{\circ}C$ (upper arm), $0.9^{\circ}C$ (calf) and the skin temperature by $0.3^{\circ}C$ (shoulder), $0.4^{\circ}C$ (upper arm), $0.5^{\circ}C$ (calf) as compared to the general flight suit. The humidity inside the summer flight suit decreased at head (7.73%), shoulder (5.86%), upper arm (5.26%), and calf (8.73%) compared to the one inside the general flight suit. Thermography showed that the air flowed through ventilation holes (neck and armpit). The design of ventilation holes applied to the summer flight suit can be applicable to overall clothing that requires thermal comfort such as dust-free garments, mechanical clothing and combat uniforms.

• Journal of Bio-Environment Control
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• v.5 no.2
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• pp.187-193
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• 1996

This experiment was conducted to investigate the influence of temperature variation by the different ventilation methods on the growth and quality of oriental melon in greenhouse of tunnel type 1. The dropping effect in temperature by ventilation types was best at type 3 and those of type 2, type 1 were in order. 2. The temperature distribution in type 3 was uniformed as air- inflow and air- outflow by wind ventilation were easier than others. Whereas the temperature of type 1 having lateral ventilation hole and type 2 having the zenith ventilation tube and lateral ventilation hole was ascended, because small ventilation area of ventilation tube and hole could not make the gravity and wind ventilation successfully. 3. When compared with air amount of three types ventilated by the temperature difference of outside and inside of tunnel type house, that of type 3 was more than those of type 1 and type 2. 4. Type 3 was better than type 2 and type 1 in lear numbers, leaf area, fruit weight, flesh thickness, malformed fruit rate, and marketable fruit rate. 5. Marketable fruit rate of all treatment at each harvesting stages was rised, as goes to the latter periods.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.2
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• pp.144-150
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• 2006

The purpose of this study is to predict outlet temperature and humidity through underground pit for the reduction of cooling load and heating load. Commonly, the underground temperature is lower than outdoor in summer but the reverse happens in winter. When the outdoor average air temperature is $25.7^{\circ}C$ during cooling periods, the average outlet air temperature through underground pit is $23.6^{\circ}C$ with 3 m-depth and 60m-length and is $22.2^{\circ}C$ with 3 m-depth and 150 m-length. When the outdoor average air temperature is $4.9^{\circ}C$ during heating periods, the average outlet air temperature through underground pit is $7.7^{\circ}C$ with 3m-depth and 60 m-length and is $10.8^{\circ}C$ with 3 m-depth and 150 m-length. The outlet air temperature is affected by more length than depth of underground pit. The diffusion ratio of outdoor humidity is $-7.7\times10^{-8}kg/s$ in cooling periods and $9.29\times10^{-7}kg/s$ in heating periods.

• Journal of Korean Biological Nursing Science
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• v.9 no.1
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• pp.71-84
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• 2007

Purpose : The Purpose of this study was to identify the physiological, psychological factors to successful weaning of mechanical ventilation in ICU patients. Method: Data was collected by interview with the use of questionnaires from 70 ICU patients, who were mechanically ventilated more than 3days at Y university medical center. Data was analyzed with descriptive statics, t-test, and $x^2$ test, and Pearson Coefficient Correlation using SPSS WIN 12.0 program. Result: ICU patients with mechanical ventilator during weaning period reported high levels of anxiety, moderate levels of stress, and fatigue. The physiological, psychological factors influencing ventilator weaning success were RSBI(p=0.007), stress(p=0.009), anxiety(p=0.020), depression(p=0.040), fatigue(p=0.001), and dyspnea(p=0.010). The RSBI factor was shown to have positive correlations with ventilator care periods, $PaCO_2$, and fatigue. Dyspnea was also positively correlated with stress, anxiety, depression, and fatigue. Conclusion: This study suggests that RSBI, stress, anxiety, depression, fatigue, and dyspnea are significant factors to successful weaning from mechanical ventilation.