• Journal of Korea Technology Innovation Society
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• v.7 no.3
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• pp.555-580
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• 2004

We analyzed the effect of 6-month lagged number portability policy and introduction of common number among carriers on Korean mobile market. Our result shows that the policy change contributed to both the increase in number of mobile subscribers and decrease in dominant carrier's market share. We found that unified prefix among mobile operators is more effective than the lagged number portability policy. The carriers' profit, however, decreased a lot due to excessive marketing expenditure. We also estimated market shares of carriers up to year 2005 when full number portability policy is adopted. The results show that dominant carrier's monopolistic power will be recovered by the end of 2005 implying government's number policy itself cannot guarantee the effective competition in Korean mobile market.

• Nuclear Engineering and Technology
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• v.51 no.3
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• pp.915-921
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• 2019

Radiation damage due to neutrons has been calculated in Ni-based alloys in Wolsong CANDU reactor environments. Two damage parameters are considered: displacement damage, and transmutation gas production. We used the SPECTER and SRIM computer codes in quantifying radiation damage. In addition, damage caused by Ni two-step reactions was considered. Estimations were made for the annulus spacers in a CANDU reactor that are located axially along a fuel channel and made of Inconel X-750. The calculation results indicate that the transmutation gas production from the Ni two-step reactions is predominant as the effective full power year increases. The displacement damage due to recoil atoms produced from Ni two-step reactions accounts for over 30% out of the total displacement damage.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.7
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• pp.1089-1096
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• 1997

In this paper, Rancho Seco transient which is reported as a typical pressurized thermal shock event is postulated to be occuring in the Kori unit 1 plant, the oldest nuclear power plant in Korea. For the given material properties, transient history such as temperature and pressure, and postulated flaw, the stress distribution is obtained to calculate stress intensities for a wide range of assumed crack sizes. The stress intensities are compared with the fracture toughness, which is determined using the material properties and the distribution of the nil ductility transition temperature, to determine if cracking is expected to occur during the transient. The allowable operating year for the transient is determined and the evaluation results are discussed.

• Journal of East-West Nursing Research
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• v.20 no.1
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• pp.29-36
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• 2014

Purpose: The purpose of this study is to identify relationships among work environment, job satisfaction and turnover intention of emergency department (ED) nurses. Methods: The survey was given to 220 ED nurses which are located in G metropolitan from May 1st to July 31st of 2012. The results were analyzed by descriptive statistics, t-test, ANOVA, pearson correlation coefficients and stepwise multiple regression using SPSS WIN 19.0 program. Results: The turnover intension according to the general characteristics of the subjects has significant difference between emergency room experience, current duty satisfaction, and turnover plan in 1 year. In the correlation between work environment, job satisfaction and turnover intention of the subjects, work environment and job satisfaction have positive correlation, job satisfaction and turnover intention either job satisfaction and turnover intention have a negative correlation. Factors influencing turnover intention are job satisfaction, career and current duty satisfaction, also the full explanatory power of the model was 24.4%. Conclusion: The results indicate factors that influence turnover intention are job satisfaction, career, and current job satisfaction. We hope these result help to provide effective intervention strategies for reducing ED nurses' turnover.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.2
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• pp.98-103
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• 2002

In case of power demand forecasting, the most important problems are to deal with the load of special-days. Accordingly, this paper presents the method that forecasting long (the Lunar New Year, the Full Moon Festival) and short(the Planting Trees Day, the Memorial Day, etc) special-days peak load using neural networks and regression models. long and short special-days peak load forecast by neural networks models uses pattern conversion ratio and four-order orthogonal polynomials regression models. There are using that special-days peak load data during ten years(1985∼1994). In the result of special-days peak load forecasting, forecasting % error shows good results as about 1 ∼2[%] both neural networks models and four-order orthogonal polynomials regression models. Besides, from the result of analysis of adjusted coefficient of determination and F-test, the significance of the are convinced four-order orthogonal polynomials regression models. When the neural networks models are compared with the four-order orthogonal polynomials regression models at a view of the results of special-days peak load forecasting, the neural networks models which uses pattern conversion ratio are more effective on forecasting long special-days peak load. On the other hand, in case of forecasting short special-days peak load, both are valid.

• Clean Technology
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• v.20 no.1
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• pp.13-21
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• 2014

Because of the water scarcity caused by the increase of salinity in the underground water, seawater desalination stands out as one of the most promising solution. As there are so much energy costs in operating desalination plants, new hybrid process which is more effective should be researched. A geothermal VMD (vacuum membrane distillation) hybrid process is a competitive alternative for seawater desalination. Because geothermal energy has significant characteristics of high capacity factor to operate the power plant at full capacity for 24 hour per day, it can be a priority heat source of VMD superior to any other renewable energies such as solar and wind power. In this study, we design a geothermal VMD hybrid process, analyze it economically and finally compare the result with a case of conventional VMD process. Geothermal VMD hybrid process generates $23,822,409 of NPV (net present value) more than the conventional VMD process in case of 5% discount rate. The break-even point between these processes is 5.36 year. Sensitivity analysis indicates that steam cost is the most decisive influence variable to the economic outcome.

• The Korean Journal of Archival Studies
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• no.34
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• pp.3-28
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• 2012

The year of 2013 is the first year that the new president takes the power and administrates the national affairs. In Korea, when the new president comes, the new administration brings big changes in the politics, economy, and society. The government management style has been changed according to the orientation and styles of the new president. Public records management is a critical and effective business tool to establish and carry out the government policies as well as an essential tool for democracy. Modern democracy is based on good governance. Creation and free use of full and accurate public records makes the good communication between the government and the public possible, and people's participation in the policy-making and surveillance of government activities for public good can work. During the present administration, communication between the president and the people was cutoff and people's participation in the national affairs have been further limited. Furthermore, in the present administration, the public records management was not regarded important, Whatever new administration comes, the year of 2013 is the time for the new administration to realize again the importance of the public records management and put it back to the normal track. Here are the major issues in the public records management to be concerned and resolved; (1) to ensure technological and institutional management of the electronic records in the government and safe transfer of the massive electronic records, (2) to establish an independent national records management and archives authority to be based on good governance, (3) to innovate the public records management in the public agencies including their agency records offices (RMO) and records management systems (RMS) (4) to establish local government archives and document local government policies and activities (5) supporting and promotion for documentation of the total society as a public service (6) expanding employment of professional records managers and archivists in the central and local governments, and standardization of professional competency and certification. In this paper, I will introduce the major issues in the public records management and suggest the policies and solutions that the Korean records professionals considered and discussed. This analysis and suggestions are the outcome of our professional considerations and discussions.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.237-237
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• 2015

The district of Marlborough has had more than its share of river management projects over the past 150 years, each one uniquely affecting the geomorphology and flood hazard of the Wairau Plains. A major early project was to block the Opawa distributary channel at Conders Bend. The Opawa distributary channel took a third and more of Wairau River floodwaters and was a major increasing threat to Blenheim. The blocking of the Opawa required the Wairau and Lower Wairau rivers to carry greater flood flows more often. Consequently the Lower Wairau River was breaking out of its stopbanks approximately every seven years. The idea of diverting flood waters at Tuamarina by providing a direct diversion to the sea through the beach ridges was conceptualised back around the 1920s however, limits on resources and machinery meant the mission of excavating this diversion didn't become feasible until the 1960s. In 1964 a 10 m wide pilot channel was cut from the sea to Tuamarina with an initial capacity of $700m^3/s$. It was expected that floods would eventually scour this 'Wairau Diversion' to its design channel width of 150 m. This did take many more years than initially thought but after approximately 50 years with a little mechanical assistance the Wairau Diversion reached an adequate capacity. Using the power of the river to erode the channel out to its design width and depth was a brilliant idea that saved many thousands of dollars in construction costs and it is somewhat ironic that it is that very same concept that is now being used to deal with the aggradation problem that the Wairau Diversion has caused. The introduction of the Wairau Diversion did provide some flood relief to the lower reaches of the river but unfortunately as the Diversion channel was eroding and enlarging the Lower Wairau River was aggrading and reducing in capacity due to its inability to pass its sediment load with reduced flood flows. It is estimated that approximately $2,000,000m^3$ of sediment was deposited on the bed of the Lower Wairau River in the time between the Diversion's introduction in 1964 and 2010, raising the Lower Wairau's bed upwards of 1.5m in some locations. A numerical morphological model (MIKE-11 ST) was used to assess a number of options which led to the decision and resource consent to construct an erodible (fuse plug) bank at the head of the Wairau Diversion to divert more frequent scouring-flows ($+400m^3/s$)down the Lower Wairau River. Full control gates were ruled out on the grounds of expense. The initial construction of the erodible bank followed in late 2009 with the bank's level at the fuse location set to overtop and begin washing out at a combined Wairau flow of $1,400m^3/s$ which avoids berm flooding in the Lower Wairau. In the three years since the erodible bank was first constructed the Wairau River has sustained 14 events with recorded flows at Tuamarina above $1,000m^3/s$ and three of events in excess of $2,500m^3/s$. These freshes and floods have resulted in washout and rebuild of the erodible bank eight times with a combined rebuild expenditure of $80,000. Marlborough District Council's Rivers & Drainage Department maintains a regular monitoring program for the bed of the Lower Wairau River, which consists of recurrently surveying a series of standard cross sections and estimating the mean bed level (MBL) at each section as well as an overall MBL change over time. A survey was carried out just prior to the installation of the erodible bank and another survey was carried out earlier this year. The results from this latest survey show for the first time since construction of the Wairau Diversion the Lower Wairau River is enlarging. It is estimated that the entire bed of the Lower Wairau has eroded down by an overall average of 60 mm since the introduction of the erodible bank which equates to a total volume of $260,000m^3$. At a cost of $$0.30/m^3$ this represents excellent value compared to mechanical dredging which would likely be in excess of $$10/m^3$. This confirms that the idea of using the river to enlarge the channel is again working for the Wairau River system and that in time nature's "excavator" will provide a channel capacity that will continue to meet design requirements.