The surface properties (water sorption and repellency, adhesion) are closely related to the surface tension of polymer solids. The critical surface tension (γ c ) and surface tension (γ s ) of a polymer solid were estimated by the contact angle method by our quantitative imaging system. BPDA (3,3',4,4'-biphenyl tetracarboxylic dianhydride)-BAPP (1,3-Bis(4-aminophenoxy) propane) polyimide was successfully synthesized. The γ c values were analyzed by a Zisman plot, a Young-Dupré-Good-Girifalco plot, and a log (1+cos θ) vs log γ L plot. The γ s value of BPDA-BAPE polyimide was evaluated using the geometric mean equation and our multiple regression analysis. The calculated values of γ S d (a dispersion component), γ S p (a polar component), γ S h (a hydrogen bonding component), and γ S were 30. 79, 9.32, 0.20, and 40.31 mN·m -1 , respectively. The γ S of BPDA-BAPP polyimide containing both a methylene group and an ether group was larger than that of the polyimide containing only a methylene group.

The moderator system of CANDU, a prototype of PHWR (pressurized heavy-water reactor), has been modeled in multidimension for the computation based on CFD (computational fluid dynamics) technique. Three CFD codes are tested in modeled hydrothermal systems of heavy-water reactors. Commercial codes, COMSOL Multiphysics and ANSYS-CFX with OpenFOAM, an open-source code, are introduced for the various simplified and practical problems. All the implemented computational codes are tested for a benchmark problem of STERN laboratory experiment with a precise modeling of tubes, compared with each other as well as the measured data and a porous model based on the experimental correlation of pressure drop. Also the effect of turbulence model is discussed for these low Reynolds number flows. As a result, they are shown to be successful for the analysis of three-dimensional numerical models related to the calandria system of CANDU reactors.

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In this study, We designed and implemented a assistant device for the standing X-ray views which is the one of the clinical X-ray imaging position. To evaluate the usability of the proposed assistant device, We choose 11 clinical patient postures that are used frequently and applied the postures to 5 volunteers. 11 images was taken from a volunteer for the patient postures. And we conducted a survey on safety and clinical usefulness, the 5 volunteers responded to the safety and 5 experts responded to the clinical usefulness. The survey results show that the volunteers feel more safe and the obtained images are very clear and clinically useful. The result for the image quality is 4.69 of 5(best) and safety is 2.84 of 3(best). It will be very profitable to both patients and hospitals by using the proposed assistant device.