Structural Analysis for Replicating Japanese Cultural Property Braids

ABSTRACT

Historic Japanese textiles from over 1000 years ago generally show marked deterioration and only very rare examples show their original forms and much information about textile reproduction has been lost. The replication of textile braids lacks systematic methodology and is still being practiced by only few individual braiding experts. The recreation of original braids as close as possible to original braids is a part of Japan’s intangible cultural heritage. The aim of this study is to clarify the decision-making procedure through which the braiding experts can decipher the original braiding structures. As a preliminary study of this project, interviews of a braid researcher and a replicating expert, Makiko Tada were performed regarding her working practices. It is important to clarify the braiding parameters for structural analysis such as the number of transits and the balance of ridges, and it became clear that the orientation of multiple colored threads plays an important role. The expert’s replicate works were also analyzed using a text-mining statistical technique to clarify the relationship of braiding parameters. The relationship between each braiding parameter and production method such as loop manipulation and Taka-dai became clear. As a result, the process of deciphering the original braid structure has been compiled in simplified workflows, which could contribute to the standardization and improvement in efficiency of replication of cultural property braids.     

Racial contacts across the Pacific and the creation of minzoku in the Japanese empire

Focusing on the work of the Japanese sociologist Koyama Eizō, this paper critically explores the development of Japanese race studies from the late 1920s to the 1940s. During this period, Japanese intellectual discourses on race developed in the context of the need to manage heterogeneous populations within the Japanese empire and contain the growing mobility of populations in and outside of the territory. Reflecting Koyama’s keen interest in racial/ethnic contacts and interdisciplinary perspectives, his intellectual work symptomatically exemplifies not only the convergence of knowledge production and the dominant imperial regime but also the transpacific implications of Japanese race studies. On the one hand, my study examines Koyama’s preoccupation with racial/ethnic contacts in relation to imperial security and also traces how his study intersected with the discourse of American social scientists who were also interested in Japanese migrations. On the other hand, the study examines how the development of the idea of minzoku in Koyama’s discourse coincided with contemporaneous attempts to mobilize diverse populations in the empire. Thus, my research reveals a complex dynamic of integration and differentiation in discourse on Japanese race studies in the interwar era.     

Random-valued impulse noise removal based on component-wise noise detector with auto-tuning function and vector median interpolation

We present a novel switching median filter for the removal of random-valued impulse noise on a color image. The present filter consists of a new noise detector with auto-tuning function, and a vector type noise remover avoiding the occurrence of the color artifacts after the noise removal. The detector has a parameter, which is automatically tuned only by using the distribution information of the noise signal without any training signals, and detects the pixel corrupted by the random-valued impulse noise with the parameter. And the detector operates in each channel independently. As a noise remover, the ordinary vector median filter is employed to interpolate only the pixel which is detected as noisy one by the detector. Through the experiments using some digital color images, the validity and the effectiveness of the present method are verified.     

Optimal parameter estimation of ε-filter employing distribution distance

As the filter which can effectively remove the small amplitude noises on digital images, the $\epsilon \mathrm{-}\mathrm{filter}$ has been proposed. In order to effectively use this filter, a smoothing parameter $\epsilon \mathrm{-}\mathrm{filter}$ should be appropriately estimated before applying it. To address this problem, the authors proposed the parameter estimation method based on Hellinger distance (HD). In the method, HD between a residual signal and assumed noise distribution was evaluated, and a parameter $\epsilon$ of the $\epsilon \mathrm{-}\mathrm{filter}$ was estimated by finding the value giving minimum distance. However, the enough discussion on use of HD has not been made.In this paper, it is attempted to utilize not only the HD, but also various distribution distances in the parameter estimation, and their performances and characteristics are compared and analyzed experimentally. Furthermore, the parameter estimation method is extended to be applicable for the vector $\epsilon \mathrm{-}\mathrm{filter}$ for the color images. Consequently, through the experiments, it is shown that L1-norm or maximum norm is appropriate as the distribution distance used in the parameter estimation methods from the view points of the simplicity of the calculation and MSE performance in the filtering.     

Estimate for the root-location of linear systems via the lyapunov matrix equation

It is well known that the Lyapunov matrix equation can be utilized to obtain the estimate for the transient behavior of linear constant systems. This paper shows that the equation gives information not only on the maximum real part of the characteristic roots of system matrix but also on other extremal values to these roots.     

On the Conditions for the Characteristic Roots of a Matrix in a Sector

Davison and Ramesh expressed equivalently the condition for the characteristic roots of a real matrix to lie within a sector by the condition for a matrixof doubled order to be Hurwitzian (1). A further generalization of their result is given in this note.     

The effects of a 4-week static stretching programme on the individual muscles comprising the hamstrings

The aims of this study were to investigate the effects of a 4-week intervention of static stretching (SS) on muscle hardness of the semitendinosus (ST), semimembranosus (SM) and biceps femoris (BF) muscles. Shear elastic modulus was measured by using ultrasound shear wave elastography as the index of muscle hardness. Thirty healthy men (age 22.7 ± 2.2 years) volunteered for this study and were randomly assigned to the SS intervention group (n = 15) or the control group (n = 15). Participants in the SS intervention group received a 4-week stretch intervention for the hamstrings of their dominant leg. Shear elastic moduli of the hamstrings were measured at initial evaluation and after 4 weeks in both groups at a determined angle. In all muscles, the shear elastic modulus decreased significantly after SS intervention. The percentage change in the shear elastic modulus from the value at initial evaluation to after 4 weeks intervention was greatest in the SM. These results suggest that SS intervention has chronic effects on reducing hardness of the hamstring muscle components, especially the SM muscle.     

Simple lightness modification for color vision impaired based on Craik–O'Brien effect

In comparison with the people having the normal color vision, the people with color vision impairment such as dichromats have the difficulty to distinguish the colors in certain combinations. This may pose an impediment of the visual communication in the recent wide spreading of the use of colors. In order to address this problem, in this paper, we propose a novel lightness modification method to improve the visibility of the color image for the color vision impaired. In the proposed method, the lightness modification is only carried out around contours of objects to realize the Craik–O'Brien effect, which is an perceptual illusion of the contrast, for dichromats. Furthermore, in the proposed method, it is tried to preserve the impression given by original color image by lessening the change of the color as possible while providing the perceptible and comprehensible color image for dichromats. Through some examples, the effectiveness and the validity of the proposed method are verified.     

Noise reduction based on iterative hybrid vector filter and detail correction employing correlation among RGB components

One of the important image processing tasks is to effectively reduce a noise from a digital image while keeping its features intact. In this paper, a new noise removal method for color images corrupted by the mixture of the impulsive and Gaussian noises is proposed. In the proposed method, firstly, a tentative output image, in which the noise is removed almost perfectly, is obtained by using the iterative robust switching vector median-based vector $\epsilon \mathrm{-}\mathrm{filter}$, which is realized by hybridizing the robust switching vector median filter and the vector $\epsilon \mathrm{-}\mathrm{filter}$ and is newly proposed here. Then the residual components between the input and the tentative output images are calculated, and image components constituting edges, corner and other image details are extracted from the residual components by using the correlation characteristic in RGB components. Consequently, a final output is obtained by adding the extracted image components into the tentative output image. The effectiveness and the validity of the proposed method are verified by some experiments using the natural color images.