• Journal of Electrical Engineering and Technology
• /
• v.13 no.2
• /
• pp.608-619
• /
• 2018

As distributed generation (DG) is connected to grid, there is new node-type occurring in distribution network. An efficient algorithm is proposed in this paper to calculate power flow for weakly meshed distribution network with DGs in different load models. The algorithm respectively establishes mathematical models focusing on the wind power, photovoltaic cell, fuel cell, and gas turbine, wherein the different DGs are respectively equivalent to PQ, PI, PQ (V) and PV node-type. When dealing with PV node, the algorithm adopts reactive power compensation device to correct power, and the reactive power allocation principle is proposed to determine reactive power initial value to improve convergence of the algorithm. In addition, when dealing with the weakly meshed network, the proposed algorithm, which builds path matrix based on loop-analysis and establishes incident matrix of node voltage and injection current, possesses good convergence and strong ability to process the loops. The simulation results in IEEE33 and PG&G69 node distribution networks show that with increase of the number of loops, the algorithm's iteration times will decrease, and its convergence performance is stronger. Clearly, it can be effectively used to solve the problem of power flow calculation for weakly meshed distribution network containing different DGs.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2010.05a
• /
• pp.321-325
• /
• 2010

Supersonic ejectors are simple mechanical components, which generally perform mixing and/or recompression of two fluid streams. Ejectors have found many applications in engineering. In aerospace engineering, they are used for altitude testing of a propulsion system by reducing the pressure of a test chamber. It is composed of three major sections: a vacuum test chamber, a propulsive nozzle, and a supersonic exhaust diffuser. This paper aims at the improvement of ejector-diffuser performance by focusing attention on reducing exhaust back flow into the test chamber, since alteration of the backflow or recirculation pattern appears as one of the potential means of significantly improving low supersonic ejector-diffuser performance. The simplest backflow-reduction device was an orifice plate at the duct inlet, which would pass the jet and entrained fluid but impede the movement of fluid upstream along the wall. Results clearly showed that the performance of ejector-diffuser system was improved for certain a range of system pressure ratios, whereas the orifice plate was detrimental to the ejector performance for higher pressure ratios. It is also found that there is no change in the performance of diffuser with orifice at its inlet, in terms of its pressure recovery. Hence an appropriately sized orifice system should produce considerable improvement in the ejector-diffuser performance in the intended range of pressure ratios.

• Journal of the Korea Fashion and Costume Design Association
• /
• v.21 no.1
• /
• pp.47-57
• /
• 2019

The purpose of the study was to explore effective satisfaction factors for continuous partnerships between fashion companies and artists. A questionnaire was developed by the researchers and results were collected from a total of 273 people who were working for a fashion company or working as an artist. Data was analyzed by the use of a frequency test, a reliability test, an exploratory factor analysis and a structure equation model analysis using AMOS 18.0. The results of the study were as follow. First, profitability and adequacy had significant effects, but awareness had no effect on confidence concerning the partnership. Second, awareness and profitability showed significant effects, but adequacy showed no effect on the flow among those in the partnership. Third, confidence had a significant effect on flow. Fourth, among the partnership factors, confidence and flow had significant effects on partnership satisfaction. Fifth, flow showed a significant effect on the intent for a continuous partnership, but confidence showed no effect.

• International Journal of Computer Science & Network Security
• /
• v.22 no.10
• /
• pp.237-245
• /
• 2022

The prominence of IoTs (Internet of Things) and exponential advancement of computer networks has resulted in massive essential applications. Recognizing various cyber-attacks or anomalies in networks and establishing effective intrusion recognition systems are becoming increasingly vital to current security. MLTs (Machine Learning Techniques) can be developed for such data-driven intelligent recognition systems. Researchers have employed a TFDNNs (Tensor Flow Deep Neural Networks) and DCNNs (Deep Convolution Neural Networks) to recognize pirated software and malwares efficiently. However, tuning the amount of neurons in multiple layers with activation functions leads to learning error rates, degrading classifier's reliability. HTFDNNs ( Hybrid tensor flow DNNs) and MRNs (Modified Residual Networks) or Resnet CNNs were presented to recognize software piracy and malwares. This study proposes HTFDNNs to identify stolen software starting with plagiarized source codes. This work uses Tokens and weights for filtering noises while focusing on token's for identifying source code thefts. DLTs (Deep learning techniques) are then used to detect plagiarized sources. Data from Google Code Jam is used for finding software piracy. MRNs visualize colour images for identifying harms in networks using IoTs. Malware samples of Maling dataset is used for tests in this work.

• Fashion & Textile Research Journal
• /
• v.23 no.1
• /
• pp.57-69
• /
• 2021

This study investigated the influences of experiential marketing components on shopping flow, store satisfaction, and purchase intention in fashion complex culture stores. The mediating effects of shopping flow and store satisfaction were also explored in the relationship between experiential marketing components of fashion multi-tasking culture stores and purchase intention. An online survey was conducted with male and female shoppers between the ages of 20 and 30 in Shanghai, China who visited fashion multi-tasking culture stores. Data from 165 participants were analyzed employing SPSS 24.0 and AMOS 24.0. There were several meaningful results of this study. First, the analysis of the subdimension of experiential marketing components (Sense, Feel, Think, and Act-Relate) clearly showed a factorial construct. Second, the components of experiential marketing showed significantly positive effects on shopping flow and store satisfaction in the fashion multi-tasking culture store. Third, the shopping flow and store satisfaction played important medicating roles in the relationship between experiential marketing components (Act-Relate on shopping flow, Sense and Act-Relate on store satisfaction) and purchase intention. The results suggest that experiential marketing components with shopping flow and store satisfaction should be promoted among Chinese consumers to enhance purchase intentions in fashion multi-tasking culture stores.

• Quality Improvement in Health Care
• /
• v.7 no.2
• /
• pp.244-261
• /
• 2000

Background : In order to cope with changes in the management environment at hospitals, increased interests are drawn in patient foodservice system on Continuous Quality Improvement Activity as the method of approaching a quality food service and effective management. Thus, as a part of this activity, this study was conducted to evaluate job flow improvement that was already performed and the results of that process at the dietetic department of a university hospital, focusing on improving management. Method : On February 15 of 1998. the dietetic department formed a job flow-improvement to decide on the priority of job flow improvement, and prepared specific action strategies and schedule of the priority: after a 5 month process period, job improvement achieved on June 15. 1998. Also, economic achievement of the task was evaluated through labor productivity analysis and cost-benefit analysis. Results : The patient food service system which was managed decentralized at the present hospital was centralized, some steps of the food service process were integrated, and quality of patient food was improved. Also, as a solution of the problems expected when conducting job flow improvement was made on food service equipments and utensils. The result of evaluating the job flow improvement that labor productivity improved by 18.2% compared to before the improvement and the result of the analysis of cost-benefit showed that Benefit-Cost (B/C) ratio was 2.22. showing financial merit on the investment. Conclusions : Continuous Quality Improvement Activity needs to be initiated and conducted in the future in various areas of hospital foodservice system in order to actively adopt to ever changing hospital management environment. In order to achieve this goal, many researches and more efforts need to be put in by people in charge of hospital food service management, and interests and support are needed from hospital policy makers.

• Nuclear Engineering and Technology
• /
• v.52 no.4
• /
• pp.755-763
• /
• 2020

The critical flow phenomenon has been studied because of its significant effect for design basis accidents in nuclear power plants. Transition points from thermal non-equilibrium to equilibrium are different according to the geometric effect on the critical flow. This study evaluates the uncertainty parameters of the critical flow model for analysis of DBA (Design Basis Accident) with the MARS-KS (Multi-dimensional Analysis for Reactor Safety-KINS Standard) code used as an independent regulatory assessment. The uncertainty of the critical flow model is represented by three parameters including the thermal non-equilibrium factor, discharge coefficient, and length to diameter (L/D) ratio, and their ranges are determined using large-scale Marviken test data. The uncertainty range of the thermal non-equilibrium factor is updated by the MCDA (Model Calibration through Data Assimilation) method. The updated uncertainty range is confirmed using an LBLOCA (Large Break Loss of Coolant Accident) experiment in the LOFT (Loss of Fluid Test) facility. The uncertainty ranges are also used to calculate an LBLOCA of the APR (Advanced Power Reactor) 1400 NPP (Nuclear Power Plants), focusing on the effect of the PCT (Peak Cladding Temperature). The results reveal that break flow is strongly dependent on the degree of the thermal non-equilibrium state in a ruptured pipe with a small L/D ratio. Moreover, this study provides the method to handle the thermal non-equilibrium factor, discharge coefficient, and length to diameter (L/D) ratio in the system code.

• Journal of Digital Convergence
• /
• v.17 no.4
• /
• pp.137-147
• /
• 2019

This paper studies the effect of content information quality of u-tourism information system on flow theory and satisfaction. The purpose of the research is to generate and propose flow-related information to satisfy tourists with content information quality. The meaning of this paper is to derive success factors for verifying satisfaction of content information quality to tourists, establish hypotheses as research models, and evaluate verification. The differentiation of this study is the design implementation of u-fusion tourism information system by combining flow relation information with flow theory. The contribution of this paper is the generation of flow related information and the elicitation of success factors of contents quality of u-tourism information system. The advantage is that tourists can be patterned by symbolization and the pattern can be illustrated. The limitations of this paper are limited to small areas, and the lack of objectivity is required and future tasks are needed to compensate for them.

• Journal of Digital Convergence
• /
• v.18 no.2
• /
• pp.385-393
• /
• 2020

Focusing on the Chinese market of MSNG (Mobile Social Network Game), perceived flow and satisfaction were designed as parameters, purchasing intention was set up as dependent variables, the purpose of present research is to analyze the factors influencing purchase intention of the paid items in mobile social games by studying the game and personal characteristics in terms of interoperability, accessibility, interesting, operability, innovativeness and challenge. Data was collected by questionnaires, Amos was employed to analyze the relationship between purchase intention and target influencing factors. Results showed that characteristics of game and consumers of MSNG have positive effects on the flow and satisfaction of paid items. Moreover, the flow of paid items in MSNG has a positive effect on satisfaction; the flow and satisfaction of paid items in MSNG have a positive effect on purchase intention. more samples and references should be involved in the further study in order to acheive an comprehensive result on comparative study of the social and cultural characteristics between Chinese MSNG and Korean counterpart.

• Transactions of Materials Processing
• /
• v.21 no.7
• /
• pp.447-452
• /
• 2012

This paper is concerned with forming of Al-Zn-Mg-Sc aluminum alloy bolts, focusing on the effects of heat treatment and age-hardening on the formability and ductile damage evolution. Both experimental and finite element studies were performed. From the experiments, it is observed that the heat treatment or the normalization of Al-Zn-Mg-Sc aluminum alloy increases its formability dramatically resulting in successful bolt forming, while the effects of age-hardening at room temperature on the stress-strain relationship and formability are not very critical. Deformation characteristics such as distribution of effective stress and strain, material flow, and ductile damage evolution during bolt forming are examined using a commercial finite element package, Deform-2D. It should be noted that the extrusion load predicted by the finite element method matches well the experiment results. The finite element predictions on the deformation characteristics support the experimental observations such as fracture of bolt head flange, material flow, and distribution of hardness.