• Composites Research
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• v.30 no.3
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• pp.175-180
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• 2017

Currently, since carbon fiber reinforced plastics (CFRPs) are lightweight and have excellent physical properties, their demand has increased dramatically. Many works have studied the CFRPs based on recycled thermoplastics. In this study, the applicability of recycled composite was evaluated using recycled polyethylene terephthalate (PET). PET was collected from waste materials used in beverage bottles and processed to produce PET films. Optimal thermoforming temperature and time were analyzed by comparing the mechanical properties with forming temperature and time difference for producing PET films. CF mat and PET film were used to determine the suitable parameters for the optimum thermoforming of CF/PET composites. The mechanical properties of each thermoforming condition were verified by bending test. The degree of impregnation of the PET film into the CF mat was evaluated by cross-sectional photographs, whereas the interfacial properties were evaluated by interlaminar shear strength (ILSS). Ultimately, it was confirmed that the thermoforming condition for forming the CF/recycled PET composites yielding the optimal mechanical and interfacial properties was at $270^{\circ}C$ for 5 minutes.

• Composites Research
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• v.30 no.3
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• pp.169-174
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• 2017

Demand of glass fiber reinforced composites (GFRC) increased with developing aircraft and defense industries using resin transfer molding (RTM) process to produce complex product. In this research, wetting, interfacial, and mechanical properties were evaluated with different Cross-linking Density by Molecular Weight of Hardener. Epoxy resin as matrices was used bisphenol-A type and amine-type hardeners with different molecular weight. Specimens were manufactured via RTM and wetting property of resin and glass fiber (GF) mat was evaluated to viscosity of epoxy and injection time of epoxy matrix. Mechanical property of GFRC was determined via flexural strength whereas interfacial properties were determined by interlaminar shear strength (ILSS) and interfacial shear strength (IFSS). The difference in mechanical property depends upon the fiber weight fraction (wt %) of GFRC by RTM as well as the different Molecular Weight of Hardener.

• Journal of applied mathematics & informatics
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• v.8 no.2
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• pp.345-360
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• 2001

Affine invariant sufficient conditions are given for two local convergence theorems involving inexact Newton-like methods. The first uses conditions on the first Frechet-derivative whereas the second theorem employs hypotheses on the mth(m≥2 an integer). Radius of convergence as well as rate of convergence results are derived. Results involving superlinear convergence and known to be true for inexact Newton methods are extended here. Moreover, we show that under hypotheses on the mth Frechet-derivative our radius of convergence can sometimes be larger than the corresponding one in [10]. This allows a wider choice for the initial guess. A numerical example is also provided to show that our radius of convergence is larger than the one in [10].

• The Journal of Asian Finance, Economics and Business
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• v.7 no.12
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• pp.593-604
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• 2020

This study analyzes human development convergence and the impact of funds transfer to the regions using σ and β-convergence analysis method. Observations were made in all Indonesia's provinces in the period 2010-2019. The coefficient of variation calculation shows a dispersion in the inequality of human development, which means that convergence occurred. This is also documented by the clustering analysis results developed in the study. The results are in line with the hypothesis of neoclassical theory, which shows the tendency for provinces with lower human development levels to grow relatively faster. The dynamic panel data approach with the GMM model shows that a model built with explanatory variables for transfer of funds to regions may lead to the process of convergence of human development - 2.21% per year or 31 years to cover the half-life of convergence. This is a consequence of the Special Allocation Fund and the Village Fund, which positively impact the convergence process, and the General Allocation Fund and the Revenue Sharing Fund with negative signs slowing the convergence process. This evidence opens opportunities to review the justification of the weighting component in determining the amount of funds transferred to the region to accelerate the convergence process of human development.

• The Pure and Applied Mathematics
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• v.15 no.1
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• pp.47-55
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• 2008

Local convergence results for three Newton-like methods in Banach space are provided. A comparison is given between the three convergence radii. Then we show that using the largest convergence radius we can pick an initial guess from with we start the corresponding iteration. It turns out that after a finite number of steps we can always use the iterate found as the starting guess for a faster method, since this iterate will be inside the convergence domain of the new method.

• The Journal of the Korea Contents Association
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• v.20 no.4
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• pp.49-61
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• 2020

Recently, the convergence of genre-mixed collaboration and technology-mixed collaboration in performance art strategically fuses different goals and different properties, satisfying anticipated demand, and developing into experimental forms that bring out convergence contents of new value. To supplement problems of convergence attempts and heighten levels of completion, the effective collaborative processes of media experts must be studied and improved. This thesis attempts to study effective collaborative production plans of convergence performance that correspond to the demands of the times through multimedia convergence performance prototypes(Live performance play + Pre-made digital animation). It categorizes performance production processes into pre-production and production and researches the effective collaborative production processes of convergence performances that utilize these two forms of media through work selection, production direction establishment, human resource constituents, production schedule plan establishment, visualization processes, and performance practices and rehearsals. Continuous research must be conducted based on convergence performance contents planning, changes in production methods, and an understanding of distinct characteristics among convergence contents for the industrial development systemization and vitalization of convergence contents to be made possible.

• Journal of Families and Better Life
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• v.27 no.5
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• pp.25-42
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• 2009

This study examines the actual state of using digital convergence products by consumers, and analyzes the expectation that consumers have regarding digital convergence products and the actual satisfaction of the digital convergence products. In addition, it analyzes factors affecting the satisfaction with digital convergence products. First, mobile phones, which 99.4% of those surveyed had, cameras, which 90.6% had, and mp3s, which 71.8% had, were found to be necessities. Second, the ratio of owning digital convergence products was 79.5%, 48.1%, and 52.4%, respectively. In the case of a mobile phones, a digital convergence type is already common. Third, regarding the reason for purchasing digital convergence products, they chose convergence products because there was no product with a simple function that they wanted to have: 38.2% in terms of a mobile phone, 47.2% for a camera, and 28.2% for an mp3. This shows that a consumer's choice was infringed in a great deal at the back of remarkable quantitative growth in digital convergence products. Fourth, the analysis of the factor regarding the consumer's expectation on digital convergence products showed 3 kinds of factors, i.e., expectation of benefit, expectation of risk, and expectation of situation. Fifth, as a result of analyzing the structural model regarding the effect on satisfaction by a consumer's expectation and the outcome on digital convergence products, all the expectations and outcomes of benefit, risk, and situation did not have a direct effect on satisfaction. Only an indirect effect through inconsistency showed a statistical significance.

• Journal of applied mathematics & informatics
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• v.29 no.5_6
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• pp.1351-1361
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• 2011

We in this paper study the complete convergence and almost surely convergence for arrays of rowwise pairwise negatively dependent(ND) random variables (r.${\upsilon}$.'s) which are dominated randomly by some random variables and obtain a result dealing with complete convergence of linear processes.

• Proceedings of the Korean Vacuum Society Conference
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• 2008.08a
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• pp.148-148
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• 2008

• Journal of applied mathematics & informatics
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• v.40 no.1_2
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• pp.69-83
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• 2022

We investigate the concept of lacunary statistical convergence and lacunary strongly convergence for sequence of sets in intuitionistic fuzzy metric space (IFMS) and examine their characterization. We obtain some inclusion relation relating to these concepts. Further some necessary and sufficient conditions for equality of the sets of statistical convergence and lacunary statistical convergence for sequence of sets in IFMS have been established. The concept of strong Cesàro summability in IFMS has been defined and some results are established.