• International Journal of Safety
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• v.5 no.2
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• pp.18-23
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• 2006

Studies have claimed that ESE (Early Streamer Emission) air terminals offer a vastly increased zone of protection over that of traditional lightning rods (Franklin rods) by causing the emission of an upward streamer/leader: The upward streamer/leader will propagate towards the tip of the downward leader at an early stage in the attachment process.. This paper shows the results of a performance evaluation test of a particular type of the ESE air terminal (called "ElecHippo") with a simple rod tested at the Korea Electrotechnology Research Institute (KERI). The corona emission current of the ElecHippo made by Yong-Jin Enterprise Corp. has also been measured at the Occupational Safety & Health Research Institute (OSHRI). The results show that the ElecHippo meets the French standard of NFC 17-102-1995. The results also verify the ESE performance by measuring the ion emission current generated in the discharge electrode gap as a function of the capacitance and inductance of the equipped devices. Finally, we propose a new method for grounding the system to reduce the lightning damage by combining the ESE air terminal, the early discharge earth plate, the lightning strike recorder and the surge protection device.

• Nuclear Engineering and Technology
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• v.53 no.4
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• pp.1100-1108
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• 2021

Supercritical water has great potential as a coolant for nuclear reactor. Its use will lead to higher thermal efficiency of Rankine cycle. However, in certain conditions heat transfer may get deteriorated which may lead to undesirable high clad surface temperature. It is necessary to estimate the operating conditions in which heat transfer deterioration (HTD) will take place, so as to establish thermal margins for safe reactor operation. In the present work, the heat flux corresponding to onset of HTD for vertically upward flow of supercritical water in a pipe is obtained over a wide range of system parameters, namely pressure, mass flux, and pipe diameter. This is done by performing large number of simulations using an in-house CFD code, which is especially developed and validated for this purpose. The identification of HTD is based on observance of one or more peak/s in the computed wall temperature profile. The existing correlations for predicting the onset of HTD are compared against the results obtained by present simulations as well as available sets of experimental data. It is found that the prediction accuracy of the correlation proposed by Dongliang et al. is best among the existing correlations.

• Journal of Korean Public Health Nursing
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• v.15 no.1
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• pp.42-55
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• 2001

The purpose of this study was to provide basic information for developing effective marketing strategies of nursing organization by identifying the correlation among internal marketing factor, nurses' job satisfaction, and organizational commitment. The subjects of this study were 256 nurses who were working in the hospital over 1 year at three university hospitals which had more than 400 beds in seoul and kyung-gido. The data were collected by self-reporting questionnaires. The instruments used in this study were the communication form scale developed by Jo(1995), the welfare scale developed by researcher, the education training scale developed by researcher, the organizational commitment scale developed by Mowday, Porter and Steers(1979). The data were analysed by the SAS package using frequency, percentage, mean, standard deviation, and Pearson's correlation coefficient. The results of this study were as follows; 1. Mean scores of internal marketing factors in nursing organization were as follows; horizontal communication 3.42, downward communication 3.32, involvement communication 3.08, upward communication 3.00, education training 2.54, welfare 2.51. The mean score of job satisfaction was 2.79 and organizational commitment was 3.00. 2. Job satisfaction was positively correlated with education training (r=0.54, p=0.0001), upward communication(r=0.49, p=0.0001). welfare (r=0.40, p=0.0001), horizontal communication(r=0.33, p=0.0001), involvement communication(r=0.25, p=0.0001) of internal marketing factors in nursing organization, but negatively correlated with downward communication(r=-0.16. p=0.0082). Organizational commitment was positively correlated with upward communication(r=0.48, p=0.0001), education training (r=0.42, p=0.0001), horizontal communication(r=0.36, p=0.0001), welfare (r=0.34, p=0.0001), involvement communication(r=0.25, p=0.0001) of internal marketing factors in nursing organization. but negatively correlated with downward communication(r=-0.20, p=0.0014). In conclusion. the results of this study showed that the internal marketing factors were highly correlated with nurses' job satisfaction and organizational commitment. Therefore, for nurses' job satisfaction and organizational commitment's improvement, it is important to develop the education training program. to improve welfare system and to actualize upward communication. among internal marketing factors.

• The Journal of Information Systems
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• v.15 no.2
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• pp.153-171
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• 2006

The objective of this research project is empirically investigating factors influencing EPP system implementation based on the degree of volatility of business environment. The results show that computes with low volatility have successfully implement ERP system compared to companies with high volatility. This research project also identified success factors of each phased chartering phase, executive participation sound assessment of business condition, good understanding of ERP system and carefully constructed case are identified as success factors. During project expenditures, participation of various groups, technical resources, prefect and change management are found to be important for successful construction. Trained users, integration of systems, well-designed process and technical and human resource are found to be success factors during shakedown phase. Managers commitment technical infrastructure, system flexibility, and adequate resource for maintenance and renewing system are identified as success factors of onward and upward phase.

• Nuclear Engineering and Technology
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• v.29 no.3
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• pp.251-259
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• 1997

This paper describes experimental investigations of helium-air exchange flows through partitioned opening and too-opening. Such exchange flows may occur following rupture accident of stand pipe in high temperature engineering test reactor. A test vessel with the too types of small opening on top of test cylinder is used for experiments. An estimation method of mass increment is developed to measure the exchange now rate. Upward flow of the helium and downward flow of the air in partitioned opening system interact out of entrance and exit of the opening. Therefore, an experiment with too-opening system is made to investigate effect of the fluids interaction of partitioned opening system. As a result of comparison of the exchange flow rates between too types of the opening system, it is demonstrated that the exchange flow rate of the two-opening system is larger than that of the partitioned opening system because of absence of the effect of fluids interaction.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1383-1387
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• 2009

As information technologies in construction field get developed, various studies and projects are in progress for improvement of construction industry. Meanwhile, web-basis online system for building materials is tending upward. However, most of the informations about classification system for building materials and specifications are not systematic yet. Most field staffs have some troubles in making full use of the material information, repeating inefficient works from constructional design to the maintenance of it. This study designed auto-categorization system classified by materials, multi-search engines, auto-converting/creating electronic catalog as well as RFID search support to provide standardized building materials information.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.11
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• pp.1732-1736
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• 2012

To increase speed up of train, in the field of catenary system, it is necessary to develop of new monitoring methods for dynamic interaction between pantograph and contact wire. Also, there is a need to develop technologies that constantly measure are from various railway structure such as uplift of contact wire, vibration of catenary, dynamic strain of contact line in tunnel. In this paper condition monitoring systems for dynamic performance of catenary systems in tunnel were proposed. An advanced method and results of field tests using high speed camera for monitoring of vertical upward movement of the grooved contact wire due to the force produced from the pantograph were presented. The proposed uplift measurement system of contact wire is expected to enhance precision of current collection quality performance assessment methods at high-speed lines.

• Proceedings of the KWS Conference
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• 2005.06a
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• pp.63-65
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• 2005

Because of simple principal and low cost, resistance spot welding has been used a lot for joining the sheet metal in automotive manufacturing process. Welding current, welding time, and force are the most important variables in resistance spot wording. Air guns have hem still used widely. The requirement of synchronizing between robot and weld-gun has become bigger as the field has been automated. The number of servo-gun in the field is trending upward because there're advantages as like to synchronize with robot and to control the stroke path and force by programming on servo-gun system. But no cleared force control method is suggested on servo-gun system until now. In this study, we proved the feedback current of the servo-motor can be used to an excellent force measuring sensor and the force is controlled by the feedback current. And we also detected force lowering during welding cycle on the servo-gun system and solved by compensated force control.

• Transactions of The Korea Fluid Power Systems Society
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• v.6 no.2
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• pp.14-21
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• 2009

The typical hydraulic hoisting system of the rack-bar type sluice gate is composed of a hydraulic supply unit using an uni-directional pump, a direction control valve, a hydraulic motor, a counter balance valve, and flow control valves. Here, the hydrostatic transmission is applied to the hoisting system of rack-bar type sluice gate to simplify the operation of gate such that the upward and downward direction of gate is simply controlled by the direction of pump rotation. The new hydraulic hoisting system is composed of a bi-directional pump, a hydraulic motor, two counter balance valves, two check valves, two pilot-operated check valves, two relief valves and a shuttle valve. The characteristics of a suggested system are analyzed by computer simulations.

• Transactions of The Korea Fluid Power Systems Society
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• v.7 no.4
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• pp.15-22
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• 2010

The typical hydraulic hoisting system of the rack-bar type sluice gate is composed of a hydraulic supply unit using an uni-directional pump, a direction control valve, a hydraulic motor, a counter balance valve, and flow control valves. Here, the hydrostatic transmission is applied to the hoisting system of rack-bar type sluice gate to simplify the operation of gate such that the upward and downward direction of gate is simply controlled by the direction of pump rotation. The new hydraulic hoisting system is composed of a bi-directional pump, a hydraulic motor, a counter balance valve, two check valves, two pilot-operated check valves, two relief valves and a shuttle valve. The characteristics of a suggested system are analyzed by computer simulations and experiments.