• Clean Technology
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• v.14 no.3
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• pp.160-165
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• 2008

The synthesis of dimethyl carbonate (DMC) with Cu catalysts was investigated in a semi-batch high-pressure reactor. DMC was synthesized via the direct oxidative carbonylation of carbon monoxide with oxygen in methanol. The corrosion rate was evaluated fie the weight change for SUS test pieces which had been added into the reactor. In order to reduce the corrosion rate without significantly losing DMC yield, various additives such as amines, olefins, and other metal salts were used. When 1-methylimidazole was used as an additive, 18.6% of DMC yield could be obtained without corrosion. If the amount of 1-methylimidazole was decreased, a high DMC yield (33.2%) could be obtained with a low corrosion rate (0.5%).

• The Korean Journal of Rehabilitation Nursing
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• v.16 no.1
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• pp.37-46
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• 2013

Purpose: This study was to identify the effects of a nurse-led education program using computerized animation video for post-operative colon cancer patients. Methods: a total of 163 patients and 51 nurses were participated in this study. With a non-equivalent control group post-test design, patients were divided into three groups (77 got traditional education, 46 were applying brochure, 40 were watching video). Twelve-item animation video and brochure about the management after discharge for post-operative colon cancer patients were developed based on patient survey and the items of Korea Healthcare Accreditation. Results: The computerized video watching group had better satisfaction than the others, but there was no significant difference about comprehension. When video was applied, satisfaction, usefulness, application, and perceived patients' comprehension of nurses were all increased. Conclusion: This video education program was developed by nurses and it had a special thing for patient to access the same program even after discharge using the authorization system. It would be helpful for nurses to be more concentrated on the direct care for hospitalized patients as well as for patients to provide self-care at home. This program would be adjusted into more various diseases and settings.

• Publications of The Korean Astronomical Society
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• v.11 no.1
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• pp.109-123
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• 1996

We have developed a 5GHz continuum receiver system. The receiver is a direct type receiver. In order to reduce the noise due to the fluctuation of the gain in the amplifiers, the system employs the Dicke switching method. We made the 5GHz low-noise amplifier and the bandpass filter. The low-noise amplifier gives ${\sim}35dB$ gain and has ${\sim}210K$ noise temperature. The bandpass filter has a passband between 4.3 and 5.4GHz. We also made switch driver, video amplifiers, phase detector, and integrator. Using a 1.8 meter offset parabolic antenna, we measured the efficiency of the system. Since the antenna does not have a driver to track objects, observations were performed with the antenna fixed. The measured noise temperature of the system is ${\sim}650K$. From the observation of the blank sky, noise level was measured. It was found that the systematic noise(${\sim}0.5K$: peak to peak value) is much larger than the thermal noise. The systematic noise is possibly related to the stability of the DC power supplied to the receiver system. Besides the noise of the system, it was found that the airplanes are the very serious noise sources. We measured the radio flux of the Sun using the developed system. The observed radio flux of the Sun is ${\sim}10^6Jy$, which is close to the known value of the quiet Sun. The test observation of the Sun shows that the angular beam size of the antenna is ${\sim}2.2^{\circ}$.

• Journal of Korean Academy of Rural Health Nursing
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• v.5 no.1
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• pp.5-15
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• 2010

Purpose: This study was conducted to examine the effects of a self-control promotion program on self-efficacy, self-care and physiological indicators of patients with diabetes who live in local communities. Method: This research was designed using a nonequivalent control group pre, posttest study. Data were collected from December, 2008 through March, 2009. The participants of the study consisted of 93 patients with diabetes who live in a local community. A self-control promotion program was provided for the experimental group for 12 weeks. Data were collected through self-report questionnaires and direct measurements, and analyzed using descriptive statistics, $X^2$-test, and repeated measures ANOVA. Results: There were significant differences in self-efficacy and self-care between the experimental and control groups. However, there were no significant differences in physiological indicators such as fasting blood sugar, HbA1C, BMI, and BP between the two groups. Conclusion: The results indicate that the self-control promotion program was effective in promoting self-efficacy and self-care, which are crucial factors in controlling diabetes mellitus. However, a longitudinal study needs to be done to confirm the effects of self-control promotion programs on long-term glucose control.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.2
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• pp.101-108
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• 2013

This paper is presented an experimental study of flow boiling heat transfer characteristics of ammonia, and is focused on pressure gradient and heat transfer coefficient of the refrigerant flow inside horizontal small tube with inner diameter of 3.0 mm and length of 2000 mm. The direct heating method is applied for supplying heat to the refrigerant, where the test tube is uniformly heated by electric current. The local heat transfer coefficients were obtained over a heat flux range of 20 to $80kW/m^2$, a mass flux range of 50 to $500kg/m^2s$, a saturation temperature range of 0 to $10^{\circ}C$, and quality up to 1.0. The pressure drops increase with increasing mass flux and heat flux, and with decreasing saturation temperature. The heat transfer coefficients increase with increasing mass flux and saturation temperature in middle and high quality region. And the local heat transfer coefficient increase with increasing heat flux in low quality region. The heat transfer coefficient of the experimental result was compared with six existing heat transfer coefficient correlation. A new boiling heat transfer coefficient correlation based on the superposition model for ammonia in small tubes is developed average deviation of -0.17% and mean deviation of 10.85%.

• Journal of Korea Water Resources Association
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• v.44 no.6
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• pp.439-447
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• 2011

This study aims to test the feasibility of combined use of EFDC (Environmental Fluid Dynamics Code) hydrodynamic model and WASP7.3 (Water Quality Analysis Program) model to improve accuracy of water quality predictions of the Yongdam Lake, Korea. The orthogonal curvilinear grid system was used for EFDC model to represent riverine shape of the study area. Relationship between volume, surface and elevation results were checked to verify if the grid system represents morphology of the lake properly. Monthly average boundary water quality conditions were estimated using the monthly monitored water quality data from Korean Ministry of Environment DB system. Monthly tributary flow rates were back-routed using dam discharge data and allocated in proportion to each basin area as direct measurements were not available. The optimum number of grid system was determined to be 372 horizontal cells and 10 vertical layers of the site for 1 year simulation of hydrodynamics and water quality out of iterative trials. Monthly observed BOD, TN, TP and Chl-a concentrations inside the lake were used for calibration of WASP7.3 model. This study shows that EFDC and WASP can be used in series successfully to improve accuracy in water quality modeling. However, it was observed that the amount of data to develop inflow water quality and flow rate boundary conditions and water quality data inside lake for calibration were not enough for accurate modeling. It is suggested that object-oriented data collection systems would be necessary to ensure accuracy of EFDC-WASP model application and thus for efficient lake water quality management strategy development.

• Journal of the Korean Geotechnical Society
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• v.19 no.2
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• pp.247-254
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• 2003

While the interests in the environmental problem during the construction are increasing, the use of low noise-vibration auger-drilled pilling is increasing to solve noise and vibration problem in pilling. Therefore, in Korea, SIP (Soil-Cement Injected Precast Pile) method is mainly used as auger-drilled pilling. However, there is no proper design criteria compatible with the ground condition of Korea, so which is most wanted. To improve and supplement this situation, direct shear tests for the friction between SIP pile skin interface and soil were executed on various conditions. Through the analysis of test results, skin friction characteristics of SIP were investigated thoroughly Also, hyperbolic model parameter fomulas which describe the friction behavior and the new non-linear unit skin friction capacity model with SM, SC soil were suggested.

• Journal of the Korean Geotechnical Society
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• v.18 no.5
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• pp.281-293
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• 2002

Empiricism has characterized the traditional methods of pile design; in essence, pile design recommendations are based on the accumulated knowledge of pile behaviour based on the construction and subsequent load testing of piles in soil and rock. In this paper, the traditional approaches to design of piles in rock will be briefly reviewed. It will be shown that the unrelated empirical relationships developed fur rock lead to considerable uncertainty in the design of piles. A new method for predicting the shaft resistance of piles socketed into rock, and based on fundamental principles is outlined. It is shown that the shaft resistance predictions of this method agree well with the field test data for rock and hard soil. It is demonstrated by way of a limited parametric study that shaft roughness and socket diameter are critical factors in the performance of piles constructed in these materials. The application of the method to piles socketed into the granites and gneisses of Korea is discussed by way of a case study and by reference to recent direct shear tests on these rocks.

• Journal of the Korean Geotechnical Society
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• v.18 no.5
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• pp.55-65
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• 2002

Model tests were performed to investigate the mechanism of lateral earth pressure on a buried pipe, which was installed in a plastic flowing soil mass undergoing lateral movement. On the basis of failure mode tests, the equation of lateral earth pressure to apply Maxwell's visco-elastic model was proposed to consider the soil deformation velocity. Through a series of model tests of differential soil deformation velocity, lateral earth pressure of theoretical equation was compared with experimental results. When lateral soil movement was raised, the lateral earth pressure acting on buried pipe increases linearly with the soil deformation velocity. It shows that the lateral earth pressure on buried pipe is largely affected by soil deformation velocity. When plastic soil movement was raised, lateral earth pressure predicted by theoretical equation showed good agreement with experimental results. Also, coefficient of viscosity by theoretical equation had a good agreement with direct shear test results.

• Korea Journal of Hospital Management
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• v.17 no.1
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• pp.23-42
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• 2012

The purpose of this study is to identify the inpatient service quality at mental hospitals and to examine the effect of service quality on patient's overall satisfaction and customer loyalty. Data collection was done through conducting a survey of inpatients in three mental hospitals located in Chungnam, Korea using self administered questionnaire. The questionnaire included the modified version of 'service satisfaction scale for psychiatric patients' invented by Chul Kwon Kim and other members, which consists of five dimension of service quality: staff attitude, treatment quality, ward environment, access/cost and ward rule. Total 236 questionnaires were gathered and 219 were used for analysis. The data was analyzed by using version SAS9.2 and path analysis model was applied to test our hypothesis. As a result, the four factors of service (staff attitude, treatment quality, ward environment and ward rule) were extracted, which counted for 62.89% of the common variance. Moreover, Cronbach Alpha showed relatively high internal consistency of answer, all exceeding 0.6. According to the study, ward environment and treatment quality turned out to have direct influence on the patient's satisfaction. In addition, staff attitude and overall satisfaction directly influenced the customer loyalty while ward environment and ward rule indirectly had influence using overall satisfaction as a medium. In conclusion, in order to enhance the satisfaction and customer loyalty in mental hospitals, efforts in improving environmental service quality in particular is highly demanded.