We have prepared organic conducting nanocomposite inks which utilize polypyrrole as conducting parts and small silica particles as dispersants. The nanocomposite inks of polypyrrole and silica represent a potentially useful processable form of polypyrrole, a normally intractable conducting polymer. Transmission electron microscopy studies confirm that the polypyrrole-silica nanocomposites are made up of microaggregates of the original small silica particles, which give rise to a distinctive “raspberry” particle morphology. The particle diameter of the nanocomposites as measured by the TEM observation can be varied over the range 160-270nm depending on the colloid synthesis conditions. The electrical conductivities of polypyrrole-silica nanocomposite inks are lower by an order of magnitude relative to bulk powder prepared under the same condition. We confirmed that these polypyrrole-silica nanocomposites can be utilized as inkjet inks due to their high colloid stabilities.

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Time-of-flight (TOF) method is conventional method for measuring of charge transfer properties. However, this method has some drawbacks such as irradiation of UV light, application of high voltage, and limitation of film thickness. Impedance spectroscopy (IS) method can measure the charge mobility without serious damage of the device. In this study, we analyzed charge mobility of polymer film containing triphenylamine derivatives by using IS method and compared the properties with those measured TOF method. As a result, Poole-Frenkel type electric field dependence of the hole mobility was obviously obtained as well as conventional TOF method. Calculated mobility on the order of 10^-6cm²/Vs from the IS method also corresponded to the mobility calculated from the TOF method. In addition, Gaussian disorder model analyses of the films were applicable for evaluation of charge transport parameters by using the IS method.

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Electrochromism (EC) is defined as reversible color change induced by electrochemical reaction, which is applicable to electronic paper and smart window. We have reported a silver deposition-based EC cell which showed reversible optical changes between clear transparent, silver-mirror, and black state. The surface structure of the electrode is considered to be a key factor on the difference in the optical states of this EC cell. In this research, we investigated the effects of the surface structure of the electrode on morphology of the deposited silver and its optical states.

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Japanese Painting and calligraphy is mounted in “Kakejiku”(hanging scroll), “Kansu”(Hand scroll), “Byobu”(Folding screen), “Husuma”(Sliding door), “Gaku”(Picture frame), “sassi”(Booklet), “Gacho”(Picture book) etc.
In the process of conservation of such artworks, restoration of paintings (or calligraphys) that is supported by advanced science and technology and mounting procedure that is built by traditional technology are applied.
The principles of the restoration of cultural assets are that :
1. Maintaning various information of artworks.
2. Repeating restoration by 100-200 years spans.
3. Recording all information of artworks during the restoration.
This review describes restoration of Japanese paintings with “Urazaishiki”(pigment on backside of silk) in “Kakejiku”(hanging scroll) that is conducted according to above principles.
And same topics of restoration of artworks on paper, relativity of “restoration of original artworks” and “digital archives” etc. are described.

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Photograph conservation is relatively unknown in Japan despite its important role in preserving and conserving photographic materials from the past and present. As the historic value of photographs becomes more and more significant and photographs as artworks are now highly collectible objects, it is a field that needs to be considered and developed further. Degradation of photographs occurs at each stage of production, preservation and display, therefore, appropriate management and preservation measures must be taken and, if necessary, conservation treatment should be conducted. Here the author introduces basic conservation procedures and treatments as well as her experience in rescuing damaged photographs from the Great East Japan Earthquake and Tsunami in 2011.

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This article reviews redundant transforms for sparse representation of images. The term “sparse representation” here denotes a way of signal representation by a linear combination of a small number of vectors, sequences or functions. This representation is used for signal modeling and finds a lot of applications such as signal estimation, restoration and feature extraction. In order to obtain a good sparse representation, it is essential to choose a signal transform appropriately. In this article, redundancy is firstly explained as an effective property of transforms for sparse representation. Then, some problem settings of sparse representation are introduced and their solvers are overviewed. Next, redundant transforms are shown to be successfully applied to image restoration problems. Furthermore, desired properties of transforms for image processing are summarized, and then dictionary learning methods are introduced as a design technique of redundant transforms. Finally, trends of related works are summarized as concluding remarks.

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“Preservation and Open to public” is required for the valuable cultural heritages.
To meet this conflicting demand, more advanced digitization technology is needed, however, high-definition digitization of cultural assets takes time and effort, and there has been no remarkable progress in this area so far.
This paper shows the general techniques of high-definition digitization of large two-dimensional cultural heritage in recent years, and explains the background, aim and method of Hitachi, Ltd.' s digitization system which is based on the conventional digital camera to reproduce exact color and shape of the originals.
As a case of the practical use of high-definition digital data of cultural assets, digital museum which has been developed aiming to let many people enjoy the digital data of cultural assets is explained in the paper.
In conclusion, future issues and measures of high-definition digitization and its applications are mentioned.

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