• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 한국소성가공학회 1996년도 자동차부품 제작기술의 진보
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• pp.75-86
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• 1996

Three-Dimensional finite element analysis is performed using PAM-STAMP for design evaluation of automotive back door inner panel die. Gravity process by blanks own weight, binder-wrap process, and drawing process in the forming operations are sequentially simulated with Virtual Manufacturing Method. The most valuable result in this research is that 3-D FEM analysis can be applied to the design evaluation of draw die in the die try-out, though effects of mesh size and drawbead resistance force on the numerical accuracy are much sensitive. For the intensive application to draw-die design and try-out, the experimental know-hows about the forming variables such as friction coefficient, punch velocity, drawbead force, etc are necessary.

• Polymer(Korea)
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• 제27권4호
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• pp.313-322
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• 2003

The morphology of poly(ethylene terephthalate) (PET)/poly(m-xylene adipamide) (MXD-6) blends, which was prepared by adding compatibilizer and interchange reaction agent, was investigated. The morphological change in the stretched blend films was also studied. The stretched film showed a dispersed MXD-6 fibril. This fibril became finer with increasing draw ratio (DR). The addition of compatibilizer and interchange reaction agent had no effect on the improvement of interfacial adhesion but caused a defect between the continuous phase and the dispersed phase, leading to the formation of irregular fibril. The change in the superstructure of blends with composition and draw ratio was examined with light scattering (LS). The H$\sub$v/ LS patterns showed a double-cross type pattern consisting of a broad rod-like pattern and a sharp cross streak. On the basis of the model calculation of the H$\sub$v/ pattern, it was found that the appearance of the double-cross type pattern was attributed to the stacking of crystals oriented along the draw direction. The crystals were gradually oriented to the stretching direction with draw ratio. As a result, the high level of orientation was obtained fur the sample of draw ratio is 6.0.

• Membrane Journal
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• 제28권3호
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• pp.196-204
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• 2018

The anaerobic fluidized bed bioreactor (AFBR) treating synthetic wastewater to simulate domestic sewage was operated under GAC fluidization to provide high surface area for biofilm formation. Although the AFBR achieves excellent COD removal efficiency due to biological activities, concerns are still made with nutrient such as nitrogen remaining in the effluent produced by AFBR. In this study, forward osmosis membrane was applied to treat the effluent produced by AFBR to investigate removal efficiency of total nitrogen (TN) with respect to the draw solution (DS) such as NaCl and glucose. Permeability of FO membrane increased with increasing DS concentration. About 55% of TN removal efficiency was observed with the FO membrane using 1 M of NaCl of draw solution, but almost complete TN removal efficiency was achieved with 1 M of glucose of draw solution. During 24 h of filtration, there was no permeate flux decline with the FO membrane regardless of draw solution applied.

• Journal of the Korea Society of Computer and Information
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• 제23권12호
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• pp.123-129
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• 2018

The purpose of this paper is to draw a conclusion on the impact of intermediate software on enterprise results. In this paper, product innovation and product reliability are especially used as analytical factors. An exploratory analytical study is conducted on the competitiveness of intermediate software, in the hope of gaining a new understanding of the competitiveness of intermediate software. Data are analyzed using such quantitative analytical tools as SPSS and AMOS. Using reliability analysis, validity analysis and structural equation model analysis, the final results are achieved. According to the analysis results, we can draw the following conclusions: the competitiveness of intermediate software has a positive impact on the innovation of software products. The competitiveness of intermediate software doesn't have a positive impact on the reliability of software products. Product innovation has a positive impact on enterprise results. Product reliability also has a positive impact on enterprise results. By analyzing the conclusions, we can make certain suggestions and draw implications on the competitiveness of China's software industry.

• Journal of Korean Society of Environmental Engineers
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• 제38권9호
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• pp.476-481
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• 2016

Pressure retarded osmosis (PRO) is a quite new technique for power generation using an osmotically driven membrane process. In the PRO process, water permeates through a semipermeable membrane from a low concentration feed solution to a high concentration draw solution due to osmotic pressure. This study carried out to evaluate the performance of the 8 in spiral wound membrane module using reverse osmosis concentrate for a draw solution and reverse osmosis permeate for a feed solution. Three different flowrates of draw and feed solution, such as 2.4 L/min, 5.0 L/min, and 10.0 L/min were used to estimate the power density and water flux under various range of hydraulic pressure differences between 5 bar and 30 bar. In addition, the effects of feed and draw solution concentration, flowrate, and mixing ratio on 8 in spiral wound PRO membrane module performance were investigated in this study. As major results, increases of the draw solution concentration lead to the improvement of power denstiy, and water flux. Also, increase of flowrate resulted in the improvement of power density and water flux. In addition, optimal mixing ratio of draw and feed solution inlet flowrate was found to be 1:1 to attain a maximum power denstiy.

• Membrane Journal
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• 제23권5호
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• pp.343-351
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• 2013

This study is to investigate the effects of the draw solution concentration on forward osmosis desalination performance using blended fertilizer as draw solution. As the concentration of blended fertilizer solution (draw solution) increased, the water permeate flux increased nearly linearly, but PR (performance ratio) was reduced. Using sea water and deionized water as the feed solution, respectively, at the blended fertilizer solution of 600 g/L $H_2O$, the PR obtained were 5.39 and 6.50, respectively. And as the concentration of blended fertilizer solution increased, the reverse solute flux for nitrogen (N), phosphorus (P), and potassium (K) increased nearly linearly, but specific reverse solute flux for them was reduced. The reverse solute flux and specific reverse solute flux became higher in the order of N > K > P.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 한국정밀공학회 1994년도 추계학술대회 논문집
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• pp.240-245
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• 1994

Experiments on the drawability of squared boxes have been performed under various working conditions. In the present work, the pattern of material flow and the local change in the thickness of shell are used as the measures of drawability, and they are measured using the photo-etching technique. The effects of the size of draw bead, the magnitude of blank holding force and the condition of lubrication on the drawability of squared boxes have been analyzed.

• Transactions on Electrical and Electronic Materials
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• 제14권6호
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• pp.283-290
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• 2013

This paper illustrates the possibilities of using the program ATP-Draw (Alternative Transient Program) for the modeling of power networks to study power quality problems with highly detailed analyses. The Program ATP-Draw is one of the most widespread and oldest programs. A unique characteristic of this program is its public domain and the existence of forums and study committees where new application cases and modification are presented and shared publicly. In this paper, to study the propagation of harmonics through a power network, a part of an industrial power network was modeled. The network contains different types of electric components, such as transformers, transmission lines, cables and loads, and there is a source of harmonics that injects $3^{rd}$, $5^{th}$, $7^{th}$, $9^{th}$ and $11^{th}$ harmonic currents into the network, causing a distortion of the wave form of the currents and voltages through the power network.

• Knowledge Management Research
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• 제16권4호
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• pp.69-87
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• 2015

Given the huge number of data produced by its users, SNS is a great source of customer insights. Since viral trends in SNS reflect customers' direct feedback, companies can draw out highly meaningful business insights when such data is effectively analyzed and managed. However, while the importance of understanding SNS big data keeps growing, the methods for analyzing atypical data such as SNS postings for business insights over product has not been well studied. This study aims to demonstrate the way to exploit topic modeling method to support marketing strategy generation and therefore leverage business process. First, we conducted topic modeling analysis for twitter data of Apple and Samsung smartphones. Then we comparatively examined the analysis results to draw meaningful market insights about each smartphone product. Finally, we draw out a strategic marketing recommendation for each smartphone brand based on the findings.

• Textile Coloration and Finishing
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• 제16권1호
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• pp.5-9
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• 2004

This research surveys the threadline instability on the belt texturing machine according to the 1st heater temperature, draw ratio and velocity ratio. the threadline instability to the time, which is called surging phenomena, is analysed with variations of draw ratio and velocity ratio. In addiction, the surging phenomena is investigated with the variation of the untwisting tension and false twist mechanism on the belt texturing machine. The breaking strain, modulus and yam unevenness of the DTY along the yarn length are measured and analysed with the surging phenomena which is due to untwisting tension variation on the threadline according to the draw ratio, 1st heater temperature and velocity ratio.