• Journal of Korean Academy of Fundamentals of Nursing
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• v.11 no.3
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• pp.344-352
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• 2004

Purpose: The purpose of this study was to identify the effect of aroma therapy on exam syndromes and temporary fatigue of senior high school students who are preparing to take college entrance exams. Method: This study was a pre-experimental research using a one-group pre-post test design and was conducted between April and July 2003 with 35 high school students. A pre-post test was used to measure long-term exam syndromes and temporary fatigue during the first period of school. Paired t-test was used. Aromas were given using an aroma electrical lamp, aroma necklet with basic oils of rosemary and lemon. According to the condition of the students, one or two oils were added: peppermint, pine, eucalyptus and Clary-Sage. Results: After two months (May, June), the result of administering aroma therapy to senior high school students showed in June there was a decrease in principal exam syndromes such as eye fatigue, headache, shoulder pain, neck stiffness, back pain, and common cold, and there was an increase Un study concentration during the two months. However, in May, there were no significant effects. The reason may have been a strong extraneous factor from midterm exams that would affect their college entrance. Conclusion: According to these results, if we use aroma oil carefully, with evidence-based applications, aroma therapy can have a positive effect on senior high school students who are preparing for the college entrance exams.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.238-239
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• 2006

Nozzle geometry influences gas dynamics making sprayed particle behavior one of the most important parameters in cold spray process. Gas flows at the entrance convergent section of the nozzle takes place at relatively high temperature and are subsonic. Thus, this region is a very suitable environment for heating spray particle. In this study, numerical simulation and experiments were conducted to investigate the effect of nozzle contour, entrance geometry of nozzle and powder injection position at nozzle on the cold spray process. The process changes were observed through numerical simulation studies and the results were used to find a correlation with coating properties.

• Proceedings of the KSR Conference
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• 1998.05a
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• pp.604-611
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• 1998

High-speed railway trains entering and leaving tunnels generate finite amplitude pressure wave which propagate back and forth along the tunnels, reflecting at the open ends of the tunnels and at other discontinuities such as ventilation shafts and the train themselves. In present day railways, the magnitudes of the pressure waves are much too small to cause structual damage, but they are a serious potential source of aural discomport for passengers on unsealed trains. Almost always do the pressure waves propagating along the tunnels lead to a hazardous impulse noise near the exit portal of the tunnel. In order to alleviate such undesirable phenomena, some control strategies have been applied to the compression wave propagating inside the tunnel. The objective of the current work is to investigate the effect of tunnel entrance hoods on the entry compression wave at the vicinity of the tunnel entrance. Three types of entrance hoods were tested by the numerical method using the characteristics of method for a wide range of train speeds. The results show that the maximum pressure gradient of compression wave can be considerably reduced by the tunnel entrance hood. Desirable hood shape for reduction of the pressure transients and impulse noise was found to be of abrupt type hood with its cross-sectional area 2.5times the tunnel area.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.2
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• pp.50-59
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• 1997

When a front head of train enters a tunnel at a high speed, compression wave is generated at tunnel entrance due to the confinement effect and propagated along the tunnel with sound of speed. The propagated compression wave is reflected at tunnel exit due to abrupt pressure change at passage. The reflected wave is expansion pressure wave. And when the rear head of train goes through the tunnel entrance, another expansion pressure wave is generated and propagated along the tunnel. The pressure drop occurs seriously around train when the two expansion pressure waves come cross on train in the tunnel. In order to reduce the pressure drop, the compression wave front must be controlled because the intensity and magnitude of pressure drop is nearly proportional to that of compression wave at tunnel entrance. This study relates to reduction of the pressure wave gradient with respect to tunnel entrance shape change with various kind of angle and rounding. The results show characteristics of wave propagation in tunnel, usefulness of characteristic curve to estimate proper time domain size in numerical study and measuring time in actual experiment. Also rounding is contributed to improve pressure wave front even if its radius is very small at tunnel entrance. In order to improve of pressure wave front at tunnel entrance, proper angle is prefered to rounding with big radius and an angle of around 14$^{\circ}$ is recommended according to this simulations, And it is expected to reduce additional pressure drop in tunnel when the location and the size of the internal space for attendant equipment are considered in advance.

• Journal of the Korean Society of Propulsion Engineers
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• v.10 no.2
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• pp.46-52
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• 2006

Techniques used for thrust vector control in rocket motors are mainly classified nozzles installed mechanical interference on the expansive region of nozzle(such as jet tabs and jet vanes) and movable nozzles(such as ball&socket and flexible seal). Using the numerical analysis and cold-flow test, this paper evaluates the performance of supersonic nozzle with asymmetric entrance shape when the test nozzle, especially ball&socket, is tilted. Numerical result shows that the effect of the asymmetric entrance shape on the flow field is suddenly diminished at the nozzle throat and downstream is mostly free from the effect of asymmetric entrance shape. Although the calculated thrust and lateral force are less than those of cold-flow test, two results show a fairly good agreement. But the cold-flow test results indicate the effective angles calculated from measured forces are not agreement with the geometric angles.

• Journal of Arbitration Studies
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• v.19 no.3
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• pp.25-42
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• 2009

That occur in international trade disputes between the parties without resorting to a court trial on the basis of principle of government by the parties to resolve the dispute resolution in general (Alternative Disputes Resolution: ADR) agreed to, reconciliation, coordination, mediation and other methods are. Here, unlike arbitration and other dispute resolution arbitrator, the court confirmed the arbitration award came from the judge and the same shall become effective in doing international commerce dispute resolution methods are widely used. Arbitration Agreement is a contractual dispute, regardless of whether a certain law there arise about the relationship between the parties, Currently exists, future conflicts can arise in whole or in part by the arbitration agreement is to be resolved. Arbitration agreement include: the effects of out of contract arbitration proceedings, the court does not want the progress of the dispute referred to arbitration proceedings to the effect, and the presence of the parties to the arbitration agreement does not claim to knowing the defense plea that Appeals ticket of destruction that have the effect of demurrer, that the arbitration agreement are rebuttal to the rebuttal of prozesshindernde Einrede and the mediation of a plea on the merits when the first defense must be submitted to the arbitration proceedings in which the applicant until the arbitration award determined that the property dispute to court for water conservation measures to dispose of the watch was in effect for arbitration in the contract. In addition, the arbitration agreement and the court sentenced the same kinds of effects that resolved the final effect, especially at the same time the effect of foreign recognition and enforcement of the decision regarding the New York Convention arbitration award based on the recognition and enforcement of domestic and international effects are being recognized. Consequently, the arbitration agreement to take effect a valid arbitration agreement exists is determined by whether or not staying. Therefore, agreements between individual university entrance exams based on the company signed a contract regarding the effect of arbitration first, associated with individual university entrance exams, and the leading research and analysis, review, and examine the general concept of the arbitration agreement after the arbitration agreement between the parties focuses on information about the effects of study to contribute to the activation of the arbitration system is aimed at the individual university entrance exams.

• Journal of the Korean Society of Radiology
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• v.10 no.6
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• pp.435-442
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• 2016

This study was an investigation of the anode heel effect caused by changing the angle of the x-ray tube. We established the following conditions for experimental measurements: 70 kV, 30 mAs, focus-detector distance of 100cm, and a collimator setting of $35{\times}43cm^2$. The measurement points were set up at the center of the collimator and extended to each side in intervals of 3.5cm, with points A1, A2, A3, A4, A5, A6 on the anode side and points C1, C2, C3, C4, C5, C6 on the cathode side. We measured the entrance surface dose from point A6 to point C6 with each point perpendicular to an x-ray tube. And we did the same when measuring different angles of the x-ray tube from 15 to 30 degrees for every point on the anode and cathode sides. Using perpendicular x-ray tube, we found that the entrance surface dose of the A5 point was three times higher than that of the C5 point. Thus, we conclude that if the anode side is placed near highly radiosensitive organs, then there will be less radiation exposure when using a perpendicular x-ray tube. When imaging using x-ray tube angles, an angle to the cathode side can reduce the gap of the entrance surface dose on both the anode and cathode sides. When imaging areas where there are differences in thickness between the upper and lower sides, the angle to the cathode side that is closer to the thicker area can reduce the gap of the entrance surface dose and capture a higher quality image.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.14 no.3
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• pp.21-28
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• 2018

This paper presents two-step simulations to calculate the influence of blast-induced pressures on explosion-protection valves installed at the boundary between a protection facility and a tunnel entering the facility. The first step is to calculate the respective overpressure on the entrance and exit of the tunnel when an explosion occurs near the tunnel entrance and exit to approach the protection facility. Secondly, the blast pressures on the explosion-protection valves mounted to walls located near the tunnel inside approaching the protection facility are analyzed with a 0.1 ms time variation using the results obtained from the first-step calculations. The following conclusions could be derived as a results: (1) The analysis of the entrance tunnel scenario, P1, leads to the maximum overpressure of 47 kPa, approximately a half of the ambient pressure, at the inner entrance due to the effect of blast barrier. For the scenario, P2, the case not blocked by the barrier, the maximum overpressure is 628 kPa, which is relatively high, namely, 5.2 times the ambient pressure. (2) It is observed that the pressure for the entrance tunnel is effectively mitigated because the initial blast pressures are partially offset from each other according to the geometry of the entrance and a portion of the pressures is discharged to the outside.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.392-393
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• 2009

The study is aimed at studying a weakly relativistic oversized BWO with a Bragg reflector entrance of SWS. The Bragg reflector reflects microwaves, while it is open for beam propagations. By changing the boundary condition at the beam entrance, the effect of the Bragg reflector on the BWO performance is examined.

• Korean Institute of Interior Design Journal
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• v.21 no.1
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• pp.3-10
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• 2012

There is a growing awareness that physical barriers affect the level of independence of people with disabilities. Many researchers insist that barrier free design could influence independence living and quality of life of the disabled. The purpose of this study is to find out the effects of accessible design features of house and public facilities on quality of life of disabled people. A total of 189 questionnaires from the disabled who visited public welfare facilities was analyzed. In order to find out what variables among accessible features in housing and public spaces impact quality of life, multiple regression analysis was carried using SPSS 14. The results showed that accessible designs significantly influence quality of life of the disable. The main reason in which the disabled have difficulties when they move outside is a lack of accessible amenities and facilities. Particularly in house design, accessible main entrance route and accessible main entrance door, and removal of floor level significantly affects quality of life of the disabled. For public spaces, accessible main entrance and installation of ramp or removal of floor levels of main entrance and corridor increase quality of life people with disabilities. This paper suggested that the improvement in housing and public space, in which regulation or bylaws do not specify, should be made to increase accessibility for life quality of the disabled.