• Journal of Environmental Science International
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• v.16 no.7
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• pp.785-791
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• 2007

The current study evaluated the technical feasibility of the application of titanium dioxide ($TiO_{2}$) photo-catalytic air cleaners for the disinfection of bioaerosols present in indoor air. The evaluation included both laboratory and field tests and the tests of hydraulic diameter (HD) and lamp type (LT). Disinfection efficiency of photocatalytic oxidation (PCO) technique was estimated by survival ratio of bacteria or fungi calculated from the number of viable cells which form colonies on the nutrient agar plates. It was suggested that the reactor coating with $TiO_{2}$ did not enhance the adsorption of bioaerosols, and that the UV irradiation has certain extent of disinfection efficiency. The disinfection efficiency increased as HD decreased, most likely due to the decrease in the light intensity since the distance of the catalyst from the light source increased when increasing the HD. It was further suggested that the mass transfer effects were not as important as the light intensity effects on the PCO disinfection efficiency of bioaerosols. Germicidal lamp was superior to the black lamp for the disinfection of airborne bacteria and fungi, which is supported by the finding that the disinfection efficiencies were higher when the germicidal lamp was used compared to the black lamp in the laboratory test. These findings, combined with operational attributes such as a low pressure drop across the reactor and ambient temperature operation, can make the PCO reactor a possible tool in the effort to improve indoor bioaerosol levels.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.4
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• pp.439-445
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• 2016

Recently, a large number of researches about concrete containing high volume fly-ash(HVFA) have been carried to obtain carbon dioxide reduction, resource recycle and durable option in concrete industry. The quality of fly-ash such as chemical composition and fineness has high variability due to the differences of used fuels, operation condition in power plant. The aim of this study is to investigate the performances of fly-ash cement mortar containing different type of fly-ashes. The basic analysis of fly ash such as chemical composition, SEM image analysis were performed. Many mortar specimens were fabricated to evaluate the properties (compressive strength, drying shrinkage and carbonation) of mortar with various fly ash. From the test results, the quality of each fly ash must be considered and fully weighted in fly ash concrete.

• International Journal of Fluid Machinery and Systems
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• v.4 no.1
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• pp.179-190
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• 2011

The swirling flow developing in Francis turbine draft tube under part load operation leads to pressure fluctuations usually in the range of 0.2 to 0.4 times the runner rotational frequency resulting from the so-called vortex breakdown. For low cavitation number, the flow features a cavitation vortex rope animated with precession motion. Under given conditions, these pressure fluctuations may lead to undesirable pressure fluctuations in the entire hydraulic system and also produce active power oscillations. For the upper part load range, between 0.7 and 0.85 times the best efficiency discharge, pressure fluctuations may appear in a higher frequency range of 2 to 4 times the runner rotational speed and feature modulations with vortex rope precession. It has been pointed out that for this particular operating point, the vortex rope features elliptical cross section and is animated of a self-rotation. This paper presents an experimental investigation focusing on this peculiar phenomenon, defined as the upper part load vortex rope. The experimental investigation is carried out on a high specific speed Francis turbine scale model installed on a test rig of the EPFL Laboratory for Hydraulic Machines. The selected operating point corresponds to a discharge of 0.83 times the best efficiency discharge. Observations of the cavitation vortex carried out with high speed camera have been recorded and synchronized with pressure fluctuations measurements at the draft tube cone. First, the vortex rope self rotation frequency is evidenced and the related frequency is deduced. Then, the influence of the sigma cavitation number on vortex rope shape and pressure fluctuations is presented. The waterfall diagram of the pressure fluctuations evidences resonance effects with the hydraulic circuit. The influence of outlet bubble cavitation and air injection is also investigated for low cavitation number. The time evolution of the vortex rope volume is compared with pressure fluctuations time evolution using image processing. Finally, the influence of the Froude number on the vortex rope shape and the associated pressure fluctuations is analyzed by varying the rotational speed.

• Journal of Dental Anesthesia and Pain Medicine
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• v.16 no.2
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• pp.95-102
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• 2016

Background: Surgery on the lower impacted third molar usually involves trauma in the highly vascularized loose connective tissue area, leading to inflammatory sequelae including postoperative pain, swelling, and general oral dysfunction during the immediate post-operative phase. This study aimed to investigate the effectiveness of preoperative injection of a single dose of 8 mg dexamethasone for postoperative pain control in lower third molar surgery. Methods: A controlled, randomized, split-mouth, prospective study involving lower third molar surgery was performed in 31 patients. The randomized sampling group was preoperatively injected, after local anesthesia, with a single dose of dexamethasone (8 mg in 2 ml) through the pterygomandibular space; 2 ml of normal saline (with no dexamethasone) was injected as a placebo. Results: The pain VAS score was significantly different on the day of the operation compared to the first post-operative day (P = 0.00 and 0.01, respectively), but it was not significantly different on the third and seventh postoperative day between the control and study groups. There was a significant reduction in swelling on the second postoperative day, and a difference between the second postoperative day and baseline value in the study group (P < 0.05). Trismus was highly significantly different on the second postoperative day and between baseline and second postoperative day between the groups (P = 0.04 and 0.02, respectively). Descriptive statistics and independent-samples t- test were used to assess the significance of differences. Conclusions: Injection of 8 mg dexamethasone into the pterygomandibular space effectively reduced the postoperative pain and other postoperative sequalae.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.15 no.1
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• pp.79-85
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• 2009

목적 : 브라운시쿼드는 대부분 척추손상과 수질외 척추 종양에서 주로 나타난다. 드물게 경추 디스크가 브라운시쿼드의 원인이 된다. 경추디스크에 의한 브라운시쿼드 증세의 수술후 물리치료 및 도수치료 결과를 보고하기 위함이다. 방법 : 50세 남자로써 브라운시쿼드 증세로 진단을 받고 수술후 좌측 팔과 다리에 운동신경에 의한 마비증세가 있었으며(팔>다리), 우측으로 감각과 온도감각이 저하된 경우이다(팔>다리). 측정방법은 통증지수(VAS), 근력(Distal PowerTracII$^{TM}$ test), 지구력(Ergometer) 측정과 심리상태(설문)를 치료전과 후를 비교하였다. 물리치료에서는 기능적 전기자극 치료와 도수치료 및 운동치료 방법을 실시하였다. 도수치료는 통증완화와 근력강화를 위한 MET, MFR, Mobilization 등을 실시하였으며, 운동은 슬링시스템 등을 이용한 운동과 견관절의 불안정을 위해 안정화운동을 실시하였다. 결과 : 이 케이스는 수술후 이상 징후가 척수압박으로 인하여 보다 넓게 통증이 나타났으며, 운동 및 감각신경이 둔해지고 온도에 대한 감각이 반대편 결손으로 나타났으며, 좌측 어깨, 팔 견갑부의 근육 마비와 우측의 감각이 떨어진 현상이 나타났다. 물리치료 후 단기목표와 장기목표에 있어서 통증과 운동 및 감각 기능이 회복되어 각각 팔 통증에서는 VAS 8 ${\rightarrow}$ 1, 상지 하지의 운동기능은 Trace ${\rightarrow}$ Good 로 평가 회복되었으며, 근력측정에서 모두 유의한 차이를 보였다. 모든 치료과정 결과에서 심리적 상태의 설문에서도 높은 점수를 얻어 긍정적 신뢰가 높아 진 것으로 나타났다. 검사결과 다리의 근력이 증가는 걷기 운동 및 에르고메터의 지구력 및 균형이 레벨1의 10분 수행능력이 레벨 20에서 30분 수행능력으로 향상되어 일상적인 활동이 가능해졌다. 결론 : 예상하지 못했던 수술 후유증(side effects)에 대한 치료과정이 환자의 심리에 심각한 부정적인 생각이 신체의 기능과 감정의 손상에 영향을 미치기 때문에 체계적이고 장기적인 치료 과정에서 기능적 향상과 더불어 정신적인 심리의 정서 안정이 매우 필요하다고 사료된다.

• Journal of Ocean Engineering and Technology
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• v.27 no.2
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• pp.107-113
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• 2013

Most natural river reach are approximately balanced with respect to sediment inflow and outflow. Dam construction dramatically alters this balance, creating an impounded river reach characterized by extremely low flow velocities and efficient sediment trapping. The impounded reach will accumulate sediment and lose storage capacity until a balance is again achieved, which would normally occur after the impoundment has become "filled up" with sediment and can no longer provide water storage and other benefits. This paper aims to investigate the sediment removal process in dam reservoir using simultaneously pressure flushing operation and vibrator machine. The main objective of this study is to identify the effect of vibrator in flushing cone dimensions. To achieve the objectives of present study, laboratory test have conducted under different hydraulic conditions such as two bottom outlets with diameter equal to 2" and 3", five discharges 0.23, 0.53, 1.21, 1.53 and 2.1 lit/s and only one water depth above the center of bottom outlets. Using the vibrator machine mounted into the reservoir and close to the bottom outlet, different frequency e.g. 20, 35 and 50 HZ, have been introduced to the deposited sediment at the vicinity of outlet. The results indicate that the volume and width of flushing cone are strongly affected by frequency of vibrations. The results indicate that the volume and width of flushing cone are strongly affected by frequency of vibrations.

• The Korean Journal of Rehabilitation Nursing
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• v.6 no.2
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• pp.226-238
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• 2003

This study was started for the purpose of providing the basic data for continous managment of kidney transplantation patients after discharge. This study was conducted on 180 patients who received renal transplants at three hospital( B, M, P) pusan, korea. The data collection was done for june 1, to August 31, 2002. General characteristics, renal transplantaton characteristics, physical characteristics, the level of compliance and the degree of educational demand were done by the number and percentage, the mean, standard deviation. The level of compliance and educational demand followed by the characteristics of general and kidney transplantation were analyzed by t-test and ANOVA. The result were as fallows; 1. Man was higher than woman such as 60.0%, Mean age was 42.5 years old, Average total duration of after operation was 5.5 years. 2. Cases of systolic blood pressure over 140mmHg were 10.0%, cases of diastolic blood pressure over 90mmHg were 22.8% and obesity factor in BMI was 15.6%. The person who daily water intake amount is 5000cc was 0.6%, the case that daily urine output is below 1000cc was 8.9%, and the case that urine output is zero was 0.6%. 3. The mean score of compliance was 77.47 point, The score in medication part was highest such as 4.67 point, that in stress situation was lowest such as 3.50 point. 4. The average score of educational demand was 154.02 point, and physical state part was 4.36 points highest, activation part was 3.48 points lowest. As a role of nurse Confirmation of compliance is very important encourage to make good through regular hospital visitation, point out the noncompliance part and then increase compliance of renal transplantation patient As well there will be maintain the normal kidney function to satisfy educational demand through continous education.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.54.2-54.2
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• 2016

Korea Microlensing Telescope Network (KMTNet) is the first optical survey system of its kind in a way that three KMTNet observatories are longitudinally well-separated, and thus have the benefit of 24-hour continuous monitoring of the southern sky. The wide-field and round-the-clock operation capabilities of this network facility are ideal for survey and the physical characterization of small Solar System bodies. We obtain their orbits, absolute magnitudes (H), three dimensional shape models, spin periods and spin states, activity levels based on the time-series broadband photometry. Their approximate surface mineralogy is also identified using colors and band slopes. The automated observation scheduler, the data pipeline, the dedicated computing facility, related research activity and the team members are collectively called 'DEEP-South' (DEep Ecliptic Patrol of Southern sky). DEEP-South observation is being made during the off-season for exoplanet search, yet part of the telescope time is shared in the period between when the Galactic bulge rises early in the morning and sets early in the evening. We present here the observation mode, strategy, software, test runs, early results, and the future plan of DEEP-South.

• Journal of Drive and Control
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• v.15 no.2
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• pp.9-21
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• 2018

The aim of this study was to develop and test a model of an auto-sensing hydraulic breaker that can automatically change its 4-step impact mode according to the rock strength using SimulationX. The auto-sensing hydraulic breaker with a 4-step variable impact mode has the advantage of obtaining optimal impact energy and impact frequency under various rock conditions compared to an auto-sensing hydraulic breaker with a 2-step variable impact mode, which has already been developed overseas. Several steps were necessary to conduct this study. First, the operation principle of the auto-sensing hydraulic breaker with the 2-step variable impact mode was analyzed. Based on the findings, an analysis model of the auto-sensing hydraulic breaker with the 4-step variable impact mode was developed (and compared with the 2-step variable impact mode) Finally, an analysis of the results established that the stepwise variable of the impact mode was implemented according to the rock strength and the difference of each impact mode was confirmed. This study is expected to contribute to the development of auto-sensing hydraulic breakers that are superior to those developed by advanced companies in foreign countries.

• Korean Journal of Occupational Health Nursing
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• v.29 no.2
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• pp.123-132
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• 2020

Purpose: This study examined the influence of nurses' communication competency, critical thinking disposition, and perception of patient safety culture on patient safety competency in armed forces hospitals. Methods: A crosssectional design was employed with a convenience sample of 204 nurse officers from four armed forces hospitals in South Korea. Data were collected through a self-administered questionnaire from August 10~23, 2019, and analyzed using descriptive statistics, t-test, ANOVA, Pearson's correlation coefficients, and multiple regression. All analyses were conducted using SPSS for Windows 21.0. Results: Patient safety competency scores were 4.35±0.40 for patient safety attitudes, 3.63±0.64 for patient safety knowledge, and 3.94±0.51 for patient safety skill. Communication competency, critical thinking disposition, and perception of patient safety culture were positively correlated with patient safety competency. Communication competency (β=.30, p=.002) and perception of patient safety culture (β=.24, p=.001) were identified as particularly important factors influencing patient safety competency. Conclusion: This study's results suggest that education programs to enhance communication competency and patient safety culture could increase patient safety competency among nurses in armed forces hospitals.