• Journal of Convergence for Information Technology
• /
• v.8 no.3
• /
• pp.71-77
• /
• 2018

In this paper, considering the oxygen sensitivity and preference pattern of the patient, the profile of the oxygen therapy of the individual is specified. And, we design a three-compartment, single compartment oxygen chamber that automatically adjusts the oxygen pressure according to the specified profile. Hyperbaric oxygen therapy is a method of providing patients with 100% oxygen higher than atmospheric pressure for therapeutic purposes. However, there is a disadvantage that the ear pain is caused by the pressure difference depending on the individual. Based on the embedded system, the proposed system creates a patient-tailored oxygen therapy profile by DB of patient's preference patterns and treatment records of oxygen therapy. If only the patient's name is entered, the oxygen chamber system can adjust the oxygen pressure automatically according to the profile pattern to maximize the oxygen treatment effect.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.16 no.1
• /
• pp.14-21
• /
• 2008

Synthetic gas is defined as reformed gas from hydrocarbon-based fuel and the major chemical species of the synthetic gas are $H_2$, CO and $N_2$. Among them, hydrogen from synthetic gas is very useful species in chemical process such as combustion. It is a main reason that many studies have been performed to develop an effective reforming device. Furthermore, other technologies have been studied for synthetic gas application, such as the ESGI(Exhaust Synthetic Gas Injection) technology. ESGI injects and burns synthetic gas in the exhaust pipe so that heat from hydrogen combustion helps fast warmup of the close-coupled catalyst and reduction of harmful emissions. However, it is very hard to understand combustion characteristic of hydrogen under low oxygen environment and complicated variation in chemical species in exhaust gas. This study focuses on the characteristics of hydrogen combustion under ESGI operating conditions using a CVC(Constant Volume Chamber). Measurements of pressure variation and flame speed have been performed for various oxygen and hydrogen concentrations. Results have been analyzed to understand ignition and combustion characteristics of hydrogen under lower oxygen conditions. The CVC experiments showed that under lower oxygen concentration, amount of active chemicals in the combustion chamber was a crucial factor to influence hydrogen combustion as well as hydrogen/oxygen ratio. It is also found that increase in volume fraction of oxygen is effective for the fast and stable burning of hydrogen by virtue of increase in flame speed.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.13 no.12
• /
• pp.6013-6021
• /
• 2012

Although there are many patients who suffer from cold hypersensitivity and have a difficult time in living daily lives due to feeling cold at room temperature, it is about true that an accurate diagnostic method and an effective remedy for a cold hypersensitivity have not been developed yet. Therefore, in order to develop traditional medicine equipment for cold hypersensitivity, we have designed new oxygen chamber system which can diagnose cold hypersensitivity with multiple bionic sensors and supply a patient optimum amount of oxygen adaptively to the extent of their illness. In particular, diverging from conventional diagnosis based on the experience of doctor and subjective statements of patient, we introduced accurate method for diagnosis in comparing between output of multiple sensors and threshold derived from clinical trials. After all, the proposed oxygen chamber system will contribute to achieving scientific evidence and manufacturing of korean traditional medicine.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2000.06a
• /
• pp.658-663
• /
• 2000

Slopping phenomena deteriorate the productivity and the stability of operation in oxygen converter process. To predict and prevent that, it needs reliable perception of the internal state of the oxygen converter chamber. Equipment was developed to measure the dynamic and static behavior of the oxygen-blowing lance 3-dimensionally and the measured signal is analyzed in relation to slopping phenomena. It was found that the behavior of the lance is strongly correlated to the change of slag foam height and the instability of molten steel behavior. So slopping phenomena can be predicted by simultaneously analyzing the measured behavior of the lance and the control factors such as the flow rate of oxygen and the height of lance.

• Journal of Integrative Natural Science
• /
• v.11 no.4
• /
• pp.209-211
• /
• 2018

A zinc oxide thin film doped with aluminum was deposited by RF sputtering. The deposition temperature of the sputter chamber was kept constant at $350^{\circ}C$, the power supplied to the chamber was 75 W, the oxygen flow rate was changed to 10 sccm and 20 sccm, and the thin film deposition time was changed to 120 and 180 minutes. The structures of the deposited zinc oxide thin films were analyzed by van der Waals method using an X-ray diffractometer. As a result of X-ray diffraction, the amount of oxygen supplied to the zinc oxide thin film increased, and the surface growth of the (002), (400), (110), and (103) planes showed a change with increasing deposition time. Moreover, as the amount of oxygen supplied to the zinc oxide thin film increased, their shape was observed to be coarse, and the thin film' s particles shape was correlated with the oxygen chemical defect introduced.

• Journal of the Semiconductor & Display Technology
• /
• v.2 no.4
• /
• pp.9-12
• /
• 2003

This paper describes a newly developed simulation environment for analysis and design of a plasma processing chamber based on first principles including complicated physical and chemical interactions of plasma, fluid dynamics of neutrals, and transport phenomena of particles. Capabilities of our simulator, named VIP-SEPCAD (Virtual Integrated Prototyping Simulation Environment for Plasma Chamber Analysis and Design), are demonstrated through a two dimensional simulation of an oxygen plasma chamber. VIP-SEPCAD can provide plasma properties such as spatiotemporal profiles of plasma density and potential, electron temperature, ion flux and energy, etc. By coupling neutral and particle transport models with a three moment plasma model, VIP-SEPCAD can also predict spatiotemporal profiles of chemically reactive species and particles exist in plasma.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.18 no.1
• /
• pp.85-90
• /
• 2014

To develop liquid propulsion engine, the development of combustion chamber must be preceded. For performance validation of the combustion chamber, the designed and manufactured combustion chamber should be tested in combustion chamber test facility (CCTF). The CCTF is the test facility to develop the combustor of rocket engine, which uses liquid oxygen as a oxidizer and kerosene as a fuel. Present paper introduces the detailed design results of compressed gas supply system of CCTF, which is planned to be installed at Naro Space Center.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• v.y2005m4
• /
• pp.265-268
• /
• 2005

A series of ignition tests had been conducted for a thrust chamber propelled by Jet A-1 and liquid oxygen with a chamber pressure of 52.5 bara and a thrust of 30 tonf. The chamber ignited by a hypergolic fluid, TEAL, keeps its first constant pressure low at $63\%$ of the design value by $61\%$ of a liquid oxygen mass flow rate and $67\%$ of fuel for 0.25 sec. The operating O/F ratio of the chamber was kept at lower values than that of the design operating condition throughout the whole ignition procedure. Surge of the chamber pressure is below $6\%$ of the design value.

• Aerospace Engineering and Technology
• /
• v.5 no.2
• /
• pp.134-142
• /
• 2006

Sub-cooling of cryogenic propellant by helium injection is one of the most effective methods for suppressing bulk boiling and keeping sub-cooled liquid oxygen before rocket launch. In order to design the cooling system, understanding of the limitations of heat and mass transfer is required. In this paper, an analytical model for the helium injection system is presented. This model's main feature is the representation of bubbling system using finite-rate heat transfer and instantaneous mass transfer concept. With this simplified approach, the effect of helium injection to liquid oxygen system under several circumstances is examined. Experimental results along with simulations of single bubble rising in liquid oxygen and bubbling system are presented with various helium injection flow rates, and with change of oxygen chamber pressure.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.16 no.6
• /
• pp.92-97
• /
• 2012

The propulsion system of space launch vehicle generates thrust by supplying oxidizer and fuel to combustion chamber. KSLV-II 2nd stage engine, currently under development by KARI, is to use liquid oxygen as a oxidizer and JET-A1 as a fuel. The 2nd stage pump-fed engine is mainly composed of combustion chamber, turbo-pump and engine supply system. To develop liquid propulsion engine, the development of combustion chamber must be preceded. For performance validation of the combustion chamber, the designed and manufactured combustion chamber should be tested in combustion chamber test facility (CCTF). The detailed design for the planned CCTF in Naro Space Center was conducted. The oxidizer supply system modeling using AMESim was performed based on the results of the detailed design, and the oxidizer supply characteristics was analyzed in this paper.