• Nuclear Engineering and Technology
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• v.28 no.2
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• pp.175-184
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• 1996

A nuclide transfer by utilizing mass transfer coefficient and barrier response function defined for each barrier is proposed, by which the final nuclide transfer rate into the sea water can be evaluated. When simple and immediate quantification of the nuclide release is necessary in the conservative aspect, using this kind of approach may be advantageous since each layered barrier can be treated separately from other media in series in the repository system, making it possible to apply separate solutions in succession to other various media. Although one disadvantage is that while flux continuity can be maintained at the interface by using the exit nuclide flux from the first medium as the source flux for the next one, there may be no guarantee for concentration continuity, this problem could be eliminated assuming that there is no boundary resistance to mass transfer across the interface. Mass transfer coefficient can be determined by the assumption that the nuclide concentration gradient at the interface between adjacent barriers remains constant and barrier response function is obtained from an analytical expression for nuclide flow rate out of each barrier in response to a unit impulse into the barrier multiplied by mass transfer coefficient. Total time-dependent nuclide transfer rate from the barrier can then be obtained by convoluting the response function for the barrier with a previously calculated set of time-varying input of nuclide flow rate for the previous barrier.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.43 no.3
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• pp.1-9
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• 2020

Interest rate spreads indicate the conditions of the economy and serve as an indicator of the recession. The purpose of this study is to predict Korea's interest rate spreads using US data with long-term continuity. To this end, 27 US economic data were used, and the entire data was reduced to 5 dimensions through principal component analysis to build a dataset necessary for prediction. In the prediction model of this study, three RNN models (BasicRNN, LSTM, and GRU) predict the US interest rate spread and use the predicted results in the SVR ensemble model to predict the Korean interest rate spread. The SVR ensemble model predicted Korea's interest rate spread as RMSE 0.0658, which showed more accurate predictive power than the general ensemble model predicted as RMSE 0.0905, and showed excellent performance in terms of tendency to respond to fluctuations. In addition, improved prediction performance was confirmed through period division according to policy changes. This study presented a new way to predict interest rates and yielded better results. We predict that if you use refined data that represents the global economic situation through follow-up studies, you will be able to show higher interest rate predictions and predict economic conditions in Korea as well as other countries.

• Journal of Korean Academy of Nursing Administration
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• v.20 no.5
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• pp.535-544
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• 2014

Purpose: This study was done to develop a schematized alarm-managing manual for continuous renal replacement therapy (CRRT) and to investigate its effects in maintaining continuity in the patients' treatment and promptly resolving alarms when CRRT is being carried out. Methods: Sixtynurses from two medical intensive care units (ICUs) (one experimental and one control) at one hospital were asked to answer a questionnaire including their CRRT nursing competency and satisfaction with the manual. Data on alarm resolution rate were collected by analyzing existing data, such as the details of each alarm and the number of resolutions around the clock in the CRRT device. Results: The alarm resolution rate and some of CRRT nursing competency scores in the experimental group were higher than those in the control group. The experimental group was also satisfied with the manual. Conclusion: The study confirmed that the schematized alarm-managing manual can be useful for ICU nurses to resolve alarms and can be used as a guideline. Application of this manual to clinical practices and its use can therefore, be encouraged through continuous education and promotion.

• Korean Journal of Construction Engineering and Management
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• v.2 no.2 s.6
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• pp.81-89
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• 2001

Construction industry has particular properties of non-continuity of production, and non-stability of market comparing to other industries. Because of them, the practical construction cost is more difficultly recognized than in manufacturing industry, so, that is various according to many projects. Therefore, it is very hard work to standardize construction cost, and it is worthy of analyzing and measuring exactly construction cost. On this study, the trouble in producing expected construction cost with original cost calculation method is progressed by the data of cost items in complete works. On the basis of analyzing data, as expected cost of practical construction is measured, it can be referred to the method and the standard of indirect labor cost rate in construction.

• Journal of Advanced Marine Engineering and Technology
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• v.20 no.5
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• pp.82-92
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• 1996

A computer simulation with predict the fuel injection rates and the fuel injection pressure behaviors in diesel engine fuel injection systems would by very useful in designing or improving fuel injection systems. In this paper we developed computer program in order to predict the behaviors of the fuel injection rate and the injection pressure for Electronic Hydraulic Ultra-High Pressure Fuel Injection System. We've applied the continuity and momentum equations for the hydraulic phenomena and the dynamics of individual components of the Electronic Hydraulic Fuel Injection System. To solve all the equations numerically we've applied the Runge-kutta IV method. Water hammer equations were applied for the hydraulic pipe solution, and the method of characteristics was employed in our calculations. The simulation results were compared with the experimental results for: Accumulator pressure, Injection pressure and unjection rate. As a result, The simulation results agree very well with our experimental results. We found that a large accumulator and the high speed solenoid valve were required, and the compression volume of the fuel had to be as small as possible in order to acheive ultra-high pressure fuel injection.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.12 no.1
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• pp.19-26
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• 2000

A numerical model is applied for predicting two-dimensional beach and dune erosion during severe storms. The model uses equation of sediment continuity and dynamic equation, governing the on-offshore sediment transport due to a disequilibrium of wave energy dissipation. And the model also uses sediment transport rate parameter K from dimensional analysis instead of that recommended by Kriebel. During a storm, a beach profile evolves to a form where the depth at the surf zone is related to the distance seaward of the waterline. In general, the erosion in the beach profile is found to be sensitive to equilibrium profile parameter, sediment transport rate parameter, storm surge level and breaking wave height.

• International Journal of Air-Conditioning and Refrigeration
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• v.6
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• pp.56-66
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• 1998

The absorption process of water vapor in a liquid film is an important process in LiBr-Water absorption system. The composition of the gas phase, in which a non-absorbable gas is combined with the absorbate, influences the transport characteristics. In the present work, the absorption processes of water vapor into aqueous solutions of lithium bromide in the presence of non-absorbable gas are investigated. The continuity, momentum, energy and diffusion equations for the solution film and gas are formulated in integral forms and solved numerically. It is found that the mass transfer resistance in gas phase increases with the concentration of non-absorbable gas. However the primary resistance to mass transfer is in the liquid phase. As the concentration of non-absorbable gas in the absorbate increases, the interfacial temperature and concentration of absorbate in solution decrease, which results in the reduction of absorption rate. The reduction of mass transfer rate is found to be significant for the addition of a small amount of non-absorbable gas to the pure vapor, especially at the outlet of tube where the non-absorbable gas accumulates. At higher non-absorbable gas concentration, the decrease of absorption rate seems to be linear to the concentration of non-absorbable gas.

• Korean Journal of Health Education and Promotion
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• v.21 no.1
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• pp.171-182
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• 2004

Objectives： Smoking, especially among youth, has been increasing in Korea. This study was performed to evaluate the effects of a newly developing well-designed packaged smoking prevention program (PSPP) for middle school students and to propose further ideas about the program. Methods： The subjects were middle school students enrolled in one Busan city middle school. The effects of the PSPP were evaluated through intervention and follow-up. The PSPP was executed for 10 hours during the semester of middle school freshmen by the author as a position of health teacher, from 1999. After PSPP, cognitions and experiences about smoking were assessed annually from February, 2000 to 2002 by questionnaire. The responses of the educated group and the non-educated group (enrolled in the school at 1998) were compared through chi-square test and odds ratio (OR) and 95％ confidence interval (CI) using SPSS program (ver 10.0). Results： In the three years' follow-up study on the students enrolled in 1999, the proportion of habitual smoking increased significantly (p＜0.001); freshmen 0.2％, sophmore 1.7％, junior 5.0％. However, these level were lower than the results of national study； freshmen 1.1 ％, sophmorer 6.3％, junior 8.5％. Also, the risk of smoking based on the response of 'smoking is hazardous to my health' increased by higher grading. In the comparison of educated and non-educated group, the proportion of the habitual smoking was significantly lower in the educated group(5.0％) than in the non-educated group(13.5％) (OR [95％CI]＝0.33 [0.20∼0.57]). The response rate of 'smoking is hazardous to my health' was higher (OR [95％CI]＝4.42 [2.52∼7.77]), and that of 'maybe smoking in the future' was lower (OR [95％CI]＝0.43 [0.31∼0.59]) in the educated group than in the non-educated group. Conclusions： Though there is not enough information and it was a relatively short evaluation period, this PSPP is considered to be effective in smoking prevention in middle school students. Interests and continuity would be emphasized for the success of smoking prevention programs for younger subjects.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.1
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• pp.91-99
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• 2011

Adult-learners of online education have been distant from studying for a long time and are rather familiar with the old massive education. As a result, despite the excellent ability in self-control learning that results in great academic performances and academic continuity, the learners give up on learning, feeling depressed for not being able to perform their advantage, the self-control learning ability. The study developed a self-control learning model and UDL design learning model in order to establish e-mentoring system. For the analysis on results of the experiment, the researcher extracted academic grade, the rate of re-register, and the amount of total studying time after dividing new students and transfer students of H cyber university into the control group and the experimental group. In conclusion, the results showed that more satisfied the control group is, the higher academic achievements and the higher academic continuity are accomplished.

• Journal of Environmental Science International
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• v.25 no.9
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• pp.1241-1251
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• 2016

A minimum threshold for the signal to noise ratio ($SNR_{min}$) has to be set in the data processing system of wind profiler radar (WPR). The data collection rate and the accuracy of the WPR wind vector depend on the $SNR_{min}$. The WPR at Uljin is operated with an $SNR_{min}$ of 1 dB which is a relatively large threshold. We found that the accuracy and the continuity of the WPR wind vector with height were directly related to the variability of the SNR and vertical gradient of the squared refractive index. We investigated a quantitative method for determining a new $SNR_{min}$ for the WPR at Uljin and it was evaluated with radiosonde data. The accuracy and continuity of the wind vector from an SNR of less than 1 dB, began to decrease at an altitude of 3.5 km. Most of the SNR values were less than -3.5 dB in altitudes higher than 3.5 km. We retrieved high-accuracy wind vectors at altitudes over 3 km where measurements were deficient with an $SNR_{min}$ of 1 dB.