• 연구논문집
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• s.30
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• pp.5-13
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• 2000

The computation scheme of simulating gas turbine transient behavior was developed. The basic principles of this scheme and main input data required are described. Calculation results are presented in terms of whole operating regime of the cycle. The influence of main initial parameters such as starting engine power, moment of inertia of the rotor, fuel supplying schedule etc. on performance characteristics of has turbine during transient operation is studied In addition, bleeding air influence on transient behavior was also considered For validation of the developed code, comparison of present calculation with that of measurement data of the experimental data for the range of operating period studied.

• The Journal of the Korea Contents Association
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• v.19 no.10
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• pp.165-178
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• 2019

Start-up companies have recently emerged as an important pillar of the national economy, becoming the core of expanding new growth engines and creating jobs for the national economy. Accordingly, this study used the Start-up Behavior (opportunity discovery, opportunity utilization) as the main variable to verify the parameter effects, and empirically analyzed the factors of the start-up characteristics on the management performance of the start-up company. To achieve this goal, 221 technology-intensive start-ups 2 to 7 years old were surveyed and analyzed for 22 days from March 4 to March 25, 2019. In summary, the results of the study are as follows. First, it has been shown that "starting-up characteristics" have a positive influence on "start-up behavior." Second, it has been shown that "creative behavior" has a positive influence on "management performance." Third, the effect of "starting-up characteristics" on "start-up behaviour" was shown to be different according to "population statistical characteristics (gender, educational background). Fourth, the effect of "starting up action" on "management performance" was shown to be different according to the demographic characteristics (gender, educational background). Finally, "Start-up Action" has been shown to have a mediated effect in the relationship between "Start-up Characteristics" and "management performance."

• Architectural research
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• v.9 no.1
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• pp.39-45
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• 2007

The static behavior of continuous system is described by the elastic curve method or is approximately analyzed by a finite element method to be modeled as a discrete system. If a continuous system is constrained by linear constraints which restrict its static behavior, its behavior can be approximately described by the finite element method. It is not easy to describe the constrained behavior by continuous coordinate system. Starting from the generalized inverse method provided by Eun, Lee and Chung, this study is to expand the equation to the continuous systems, to perform the structural analysis of the beam under a uniform loading with interior spring supports, and to investigate the validity of the proposed method through applications.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.331-334
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• 2010

Operating characteristics of DGT-5 being developed by Doosan Heavy Industries & Construction Co., Ltd. for power generation service was evaluated. Starting behavior was improved by a series of tests to investigate the effect of various fuel schedule and several combination of bleed valve control. The engine showed stable operation without any instability of compressor in the full operating regime covering from start-up to load conditions. If there is a rapid change of load in the condition of synchronization to Grid, the engine can be controlled stably based on the analysis of dynamic responses of the engine to an rapid load change and a sudden load rejection.

• Journal of the Korea Society of Computer and Information
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• v.24 no.8
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• pp.159-166
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• 2019

In this paper, we propose takes network marketing as a starting point for analysis, uses the theory of purchasing behavior and enterprise performance to analyze the network marketing strategy of artistic products, incorporates the practical problems encountered by some artistic products enterprises in Zhejiang Province in network marketing into theoretical research. The theoretical model of network marketing strategy acting on enterprise performance through the intermediary effect of purchasing behavior is constructed. This paper conducted an in-depth survey of three representative core domestic companies engaged in Internet marketing of artistic products, and analyzed the questionnaires of 357 respondents. The initial model was verified by statistical tools such as SPSS and AMOS, and three conclusions were drawn: Firstly, network marketing strategies of different dimensions have different effects on purchasing behavior: pricing strategy and product strategy have significant positive effects on impulse purchasing behavior, but channel strategy has no significant impact on impulse purchasing behavior; Channel strategy and product strategy have a significant positive impact on repeated purchasing behavior, but pricing strategy has no significant impact on repeated purchasing behavior. Second, user purchasing behavior has a significant positive impact on enterprise performance. Third, network marketing strategies of different dimensions have significant direct and positive impact on enterprise performance.

• Journal of the Korean Society of School Health
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• v.16 no.1
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• pp.55-66
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• 2003

This study was conducted to evaluate the differences of perceived stress level and stress coping behavior for 360 elementary school children in rural area and 360 in urban area. The questionnaire survey was done from December 10 to December 20, 2001. The results were as follows: 1. There was no significant difference of perceived stress level between rural and urban areas, but there were significant difference of stress coping behavior between them. 2. Significant difference of perceived stress level and stress coping behavior among groups of grade was found. 3. There was significant difference of perceived stress level and stress coping behavior between male and female. 4. There was significant difference of stress coping behavior according to perceived stress levels In conclusion, perceived stress level and stress coping behavior in elementary school children were different according to their grade and sex. It is important to teach them proper stress coping method, depending on their grade and sex. But, we have to focus on the development and application of stress self-control program, which enables children to cope with stress for themselves. Based on: 1. Before starting the study, the subjects should be examined about whether they have ever been on stress education program before or not. 2. The educational environments and the development and implementation of teaching program for the proper stress coping method are needed. 3. This study was performed through the questionnaire for perceived stress level and stress coping behavior, but various methods like observation, person-to-person interview should be used for the further in-depth study.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.09b
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• pp.951-951
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• 2005

The characteristics of Boussinesq starting forced plumes were investigated in this study. Two distinct periods in the transient plume penetration were identified, namely the Period of Flow Development (PFD) and Period of Developed Flow (PDF). PFD refers to the time period whereby the penetration rate is governed by the complex vortex dynamics initiated by the exit conditions that can include vortex coalescence, vortex leapfrogging, pinching off of the head vortex from the trailing stem and the eventual reconnection. The pinch-off and reconnection leads to an overshoot of the plume front which is a common observation reported in previous studies. The penetration rate in PDF is more predictable and depends on the continuous feeding of buoyancy and momentum into the head vortex by the trailing buoyant-jet stem. Similarity solutions are developed for PDF to describe the temporal variation of the penetration rate, by incorporating the behavior of an isolated buoyant vortex ring and recent laboratory results on the trailing buoyant jet. In particular, the variations of velocity ratios between the head vortex and trailing buoyant jet are analytically computed. To verify the similarity solutions, experiments were conducted on vertical starting forced plumes using planar laser induced fluorescence (PLIF).

• Journal of the Korean Ceramic Society
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• v.44 no.9
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• pp.517-523
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• 2007

For the preparation of tricalciumaluminate $(C_3A)$ clinker, in traditional clinkering method using oxides and carbonates as a raw material, uneconomical repetition of burning have been necessary to avoid the melting of clinker by eutectic reaction in the system $CaO-Al_2O_3$. In this study, special starting raw materials for the clinker burning were prepared from a mixture of oyster shell and aluminium hydroxide by heating to $1100^{\circ}C$ and hydrating at $30^{\circ}C$. The starting raw materials, hardened body with weak hydraulic strength, were mainly composed of $C_3AH_6$ formed by resolution-precipitation mechanism of the system $CaO-Al_2O_3-H_2O$. By heating them, relatively pure $C_3A$ clinker could be obtained by one-time burning at the fairly lower temperature than that of conventional method. The easier formation of $C_3A$ clinker seemed to be caused by higher compositional homogeneity and stoichiometry of the starting materials, high surface area and crystallographic instability of the thermally decomposed products, and the catalytic effect of decomposed moisture on the early-stage crystallization of calciumaluminates. The basic hydration behavior of the clinker was also confirmed.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.2203-2206
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• 2005

A load flow and short circuit fault simulation of AC electrified railway distribution systems is presented with DIgSILENT PowerFactory software. Load flow of electrified railways distribution system with concerning multi train lines and dynamic characteristics of train load is studied for different time laps. The dynamic characteristics of train load in starting and braking conditions with different starting and stopping times and its moving positions makes the load flow complicated so there is a great need in studying the effects of electrified railways on load flow. Short circuit fault transients is also studied and simulated for both power system or traction distribution system and their effects on the operation of the train sets is investigated.

• Journal of the Korean Ceramic Society
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• v.55 no.5
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• pp.452-460
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• 2018

This study investigate changes in mechanical behaviors such as indentation load-displacement and hardness of thermal barrier coatings (TBCs) using cycling of thermal shock test. Relatively dense and porous TBCs on nickel-based bondcoat/super alloy are prepared using different starting granules, 204C-NS and 204NS commercial powers, and the effect of double layers of 204C-NS on 204NS and 204NS on 204C-NS are investigated. The highest temperature applied during thermal shock test is $1100^{\circ}C$ and the maximum number of cycles is 1,200. The results indicate that bilayered TBC showed a relatively mechanically resistant property during thermal shock cycles and that the mechanical behavior is influenced by the microstructure of TBCs by exposure to high temperature during tests or different starting granules.