Shouji Sakamoto

Interaction system based on virtual candle light

In this paper, our purpose is to develop an interaction system based on virtual candle light. The contents of this paper are as follows: First, we show how to generate reflectance distribution filter by using an actual wax candle. Secondly, we show the virtual light effect on a wall painting image can be reproduced by using the reflectance distribution filter and the Cellular Automata. Finally, we show an interaction system which changes the optical appearance of wall painting images whenever a user moves a penlight which the user holds and compares to a candle light.

Synaptic weight normalization effects for topographic mapping formation

We propose a simple topographic mapping formation model between cell layers with weight normalization. In our model, each cell layer can have an arbitrary neighborhood relation between the cells represented by an undirected graph. Thus, a topographic mapping described in this model is a map which preserves the adjacency relation. We define several learning rules, input and output type weight normalization methods. Then, we not only concentrate on a Hebbean weight modification but also investigate the effects of normalization under a non-Hebbean weight modification. We first show that when an input type normalization is adopted or without normalization, a topographic mapping is stable under the correlational type learning rule, but when an output type normalization is adopted a topographic mapping is stable under not only the correlational type learning rule but also the non-correlational one. Next, we show by computer simulations that when an output type normalization is considered we have more learning rules which yield topographic mappings than the cases when an input type normalization is adopted or without normalization.

Paper Analysis and Paper History from Ancient Chinese Paper to Japanese Washi

This paper describes about analysis for papers and old documents. The samples consist of various kinds of papers, from early 4th century documents to 20th century papers, e.g. Chinese old documents, 19th century Japanese papers and modern handmade papers from Japan, China, Taiwan and South Korea. First, we investigated about elements in the papers by X-ray Fluorescence Analysis. Most of the ancient papers from China have metal elements, Fe, Ti and Al. But most of the modern papers do not include them. Next, we also measured paper colour, and classified the papers by the paper colour data. The result shows that old papers colour is darker and yellower than modern papers one. Finally, we investigated dunhunag manuscripts from 5th century to 10th century, and tried to classify them by paper fibre analysis.

Stability of generalized topographic mappings between cell layers through correlational learning

We propose a simple topographic mapping formation model from a cell layer to a cell layer. Our model is a discrete one in that the state value of input and output cells takes 0 or 1 and input and output layers are represented by undirected graphs. A binary input pattern can be given to the network consisting of input and output cell layers. Such an input pattern can be represented by a subset of input cells. That is, a state value of an input cell takes 1 if a cell belongs to the subset, otherwise, a state value of an input cell is 0. Such a definition of an input pattern does not necessarily assume a short-range excitatory mechanism in an input layer. Thus, a topographic mapping described in this model is a map, which preserves the input pattern relation. By using the concept of input pattern separability, we showed an existence condition of certain learning rules, which are correlational. We have paid special attention to such correlational type learning rules, and have shown under the rules that topographic mappings are the only stable ones. As to the non-correlational learning rules, we also investigate the stability of generated mappings.

Paper Analysis and Database of Papers of the Pelliot Collection, Dunhuang Manuscripts

This paper introduces paper analysis and a database of papers of the Dunhuang manuscripts. We investigated old papers of the Pelliot collection, which is the Dunhuang manuscript collection, scientifically at the Bibliotheèque nationale de France (BnF). As Dunhuang documents are rare books, it is difficult to access them usually. However, we developed a nondestructive analysis method for rare books. The paper analysis produced thousands of microscopic images by high-resolution digital microscope, and the image data constitutes very important preliminary data for researchers of Dunhuang study and paper history study. Consequently, we have developed the database of papers to provide the data to researchers and conservators.