• Fire Science and Engineering
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• v.14 no.2
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• pp.14-20
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• 2000

Many pressurization systems are designed and built with the goal of providing a smoke-free escape route in the event of a building fire. A secondary objective is to provide a smoke-free staging area for fire fighters. In the present study, a computer program is developed to calculate pressure loss and flow rate at several building elements such as a room, a ]tabby a staircase and an air supply shaft. By the program as the dosing tool for the pressurization system, the capacity of the injection fan is calculated, and the design method is proposed for the optimization of the fan capacity.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.813-816
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• 2011

The actuation and leakage tests of solenoid valve for propellant tank pressurization system have been conducted. The response time of solenoid valve manufactured is satisfactory to perform requirement. However, leakage was found at the upper part seat of relief valve inside solenoid valve. Solenoid valve was disassembled in order to discover leakage causes. We found out that the upper seat of relief valve was damaged. Through this study, the development possibility of propellant tank pressurization solenoid valve was confirmed.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.11a
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• pp.113-115
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• 2006

Consulting Stout & Snell's paper[1], design approaches for the pressurization system for a launch vehicle are introduced. We have outlined the typical system requirements and a dynamic model of the pressurization system. A brief summary on the control loop design for multiple on-off valve control systems has been also presented.

• Fire Science and Engineering
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• v.4 no.1
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• pp.3-12
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• 1990

This study is to Present the air Pressurization system of staircase as a way to decrease the injury of human life which is suffocated by smoke when the fire break out in building. 1) The best among an air pressurization system of stairshaft Is multiple air Injection system established to be situated an air injection point in each layer. 2) If the air pressurization system is also applied to the elevator accessory room to use commonly, it can prevent from the smoke spreading and pollution inside building caused by stack effect of elevator shaft. 3) For the reasonable and safe escape and air pressurization system must be carried out from the project of basic shape of building under the close cooperation with architect and fire protection expert.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.04a
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• pp.247-250
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• 2008

Pressurization is a method of ensuring that protected escape routes(staircases and lobbies) are kept free of smoke for shelterers and fire fighters by raising the air pressure in these spaces above that in the main part of the building. In this study, to estimate a pressurization, the characteristics of pressure difference in a room, a lobby, an air supply shaft at several building elements are investigated with a window, the (a fire) door and a air supply damper so that information about the importance of these experimental parameters can be obtained.

• Proceedings of the KIEE Conference
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• 2002.07d
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• pp.2445-2447
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• 2002

In this paper, CAN-based feedback control system is proposed for the pressurization system of korean high-speed train. The control performance of the system is evaluated. According to the requirement of the pressurization system A process model considering network delay and an adaptive PID control method based on the process model are proposed here. And it is shown that the proposed adaptive PID control method considering the network delay has on adequate feature compared to some other existing methods consequently it can be considered to be applied the pressurization system of korean high-speed train.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.142-147
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• 2008

This paper reports an analysis of self-pressurization in a closed cryogenic liquid storage system and its comparison with experimental data using liquid nitrogen. Partial equilibrium model(PEM), revised thermodynamic analysis of homogeneous model, has been applied for the pressurization in a closed tank. The vapor and liquid bulk temperature and the liquid-vapor interface temperature are separately calculated as their own representative values in this analysis. The analysis results of the partial equilibrium model are compared with the experimental data and other preceding homogeneous temperature models for validation.

• Journal of the Korean Society of Safety
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• v.18 no.2
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• pp.40-45
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• 2003

To evaluate the smoke control systems, the large eddy simulation turbulence model based Fire Dynamics Simulate was applied to a 2m $\times$ 2m $\times$ 2.4m room with an opening. The smoke removal rate was investigated for three different smoke control systems: ventilation, extraction and pressurization. When the opening was closed, the smoke removal rates of the smoke control systems were almost the same as expected. The pressurization system showed a lower smoke removal rate compared with the other two smoke control systems for the room with the opening, and hence the pressurization system might not be efficient for a place with large openings. It was shown that the lower extraction flowrate is, the longer time the ventilation system requires to remove smoke. From these results, the ventilation system is recommended for subway stations where several large openings exist.

• Journal of the Semiconductor & Display Technology
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• v.20 no.2
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• pp.51-55
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• 2021

With the recent development of various smartphone designs in the smartphone market, the use of curved cover glass has been required, and interest in curved glass production has increased. In this paper, we designed a pressurization system that simplified the size of the system using a wedge amplification mechanism for smartphone curved glass molding systems. The pressurization system consisted of a linear motor, a wedge, and a force sensor. The wedge was used to amplify the force, and the piezoelectric sensor was used to measure the force. In addition, the proposed amplification mechanism was confirmed to have an error of 1.27% through an experiment compared to the simulation, and the pressurization error of 0.76% for the pressurization profile 3,500N was verified through an experiment.

• Journal of Aerospace System Engineering
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• v.11 no.3
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• pp.8-15
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• 2017

In this paper, an equivalent brake hydraulic circuit with a piezoelectric hydraulic pump was constructed, and load pressure control for better pressurization/depressurization characteristics was conducted. To understand pressurization/depressurization characteristics of the equivalent hydraulic circuit, the relation between the load pressure and the input voltage was revealed experimentally. Experiments were also conducted to observe effect of the solenoid valve on depressurization characteristics. In the pressurization experiment, it was validated that transient response time required to achieve desired load pressure may be reduced through voltage control to change pressurization gradient. By applying the valve on/off time control and voltage control, it was also possible to reduce response time in the depressurization process. Therefore, transient response time may be improved within 10ms for pressurization and within 30 ms for depressurization using the control technique suggested in this study. The load pressure control method proposed in this study is useful for controlling load pressure of a hydraulic brake system with the piezoelectric hydraulic pump.