Curing behavior and structural property of an inorganic compound added urea-formaldehyde(UF) and urea-melamine-formaldehyde(UMF) were studied. In addition, tensile strength and formaldehyde emission of plywoods made of those resin binders were studied. Curing temperature and structure were not changed, but tensile strengths of plywoods manufactured both with a UF resin and a UMF resin were decreased slightly as increased amount of inorganic compound. Formaldehyde emissions from plywoods were reduced as increased amount of inorganic compound. Wheat flour as an extender was helped to reduce of formaldehyde emission. From the result of this study it might be estimated that using appropriate amount of inorganic compound and proper resin system can be strengthened bond strength and reduced formaldehyde emission.

The influence of adding urea to phenol-formaldehyde (PF) resins as a co-polymer component were investigated aiming at synthesizing useful phenol-urea-formaldehyde resins. Urea was added at 10% by total resin weight. Several methods for the addition of urea to the PF resins during synthesizing resins to see the co-polymerization occurs between urea and PF resins. The urea was added at the beginning, at three different middle stages, and at the end of PF resin synthesis. The copolymerized methylene bridges between phenol and urea molecules were not observed by 13C-NMR; no signal around 50ppm. The curing of urea-modified PF resins, evaluated by dynamic mechanical analysis(DMA), showed some differences among the resins. DMA gel times ranged from 2.75 min to 3.25 min and the resins made with earlier urea additions showed slightly shorter gel times. The longest cure time and gelation time was observed for the resin PFU. Catalyst effects on the DMA cure time values of resins were not significant with different amounts of catalyst or different types of catalyst for all resins tested. Gel times of urea-modified PF resins shortened the most by triacetin catalyst

Purpose – There are common factors both in Technology Readiness and Acceptance Model and Technology Paradox Theory which can be put together and made in one unified model. The unified model can provide the following merits. First, the unified model is simple but contains factors of the models. Second, the unified model can clarify the process of technology acceptance of common consumers. Third, the unified model can provide the opportunities to analyze the negative sides of new technology, thus find ways to improve the level of acceptance by general consumers. Research design, data, and methodology – The 450 questionnaires were handed out to people around Seoul and 421 were collected. Except insincere and wrong-marked ones, 402 were used to analyze. SPSS program was used to analyze. Factor analysis, regression analysis was conducted to test the hypotheses. Results – By analyzing sub-factors of both models and binding the common factors in one category, we accomplish one model. And we tested the model by empirical method. The results show that the results from the unified model are almost same as the results from the two models. In other words, the unified model works. Conclusions – Explaining one state of affair by two different method is in some sense distracting attention. By devising a new model including factors of both models, we can explain the affair more straightforward and efficiently. At first the technology acceptance model was devised to explain the technology users in an organization and the following tests and revised models were for the similar purposes. However, as on-lone activities including contracts have been expanded and become important, consumers as the technology uses have emerged as first factor to consider. In accordance models to explain this situation has been suggested. The model suggested in this research is one of the models but it has the following merits. That is, it is simple but has strong explanation power, it can clarify the process of technology acceptance of common consumers by containing negative sides of consumer conception, and thus, it can provide the opportunities to analyze the negative sides of new technology, also find ways to improve the level of acceptance by general consumers.

Purpose – Aviation control, navigation, and aircraft control in the air transportation area are very specialized. Each part is in progress for safety, efficiency, automation, and further. On the other hand co-work among each part including knowledge sharing has been inattentive for many reasons. The purpose of this research is to show how practicians and professionals in the air transportation area perceive the issue of knowledge sharing and to recall the necessity of knowledge sharing in the area. And we try to find ways to activate the knowledge sharing in the area. Research design, data, methodology – For the research, we inquired into whether practicians and professionals think knowledge sharing can effect safe aviation positively or not and what steps are necessary to activate knowledge sharing in the area. We adopted survey method using questionnaires for current practicians and interview for specialists. The survey and interview results were analyzed using regression analysis and AHP method. The interview for specialists and analyzing the results using AHP was to investigate what are the precedence factors to activate the knowledge sharing. Results – First, practicians perceive that knowledge sharing will affect aviation safe positively. Second objective knowledges such as, tower air traffic control procedure of aviation control area, flight principle and structure of aircraft control area, instrument landing system of navigation area, for knowledge sharing of each area were identified. Also the precedence factors such as, knowledge absorbability of personal factor, personal expectation of result of expectation factor, leadership of management of Structure factor, method of knowledge spread of application factor for knowledge sharing were found. Conclusions – Knowledge sharing for practicians and professionals in the aviation area is very important especially from the perspective of safety. However, for various many reasons including the environment of each special area that focusing on their own area, knowledge sharing has not been emphasized. We found that practicians in the area feel that knowledge sharing is necessary and helpful. For it, each practician’s active participation is the most important and many ways such as chatting room to share knowledge are to be developed. And the organization culture should be changed to encourage knowledge sharing.