Multi-disformal invariance of nonlinear primordial perturbations

We study disformal transformations of the metric in the cosmological context. We first consider the disformal transformation generated by a scalar field $\phi$ and show that the curvature and tensor perturbations on the uniform $\phi$ slicing, on which the scalar field is homogeneous, are non-linearly invariant under the disformal transformation. Then we discuss the transformation properties of the evolution equations for the curvature and tensor perturbations at full non-linear order in the context of spatial gradient expansion as well as at linear order. In particular, we show that the transformation can be described in two typically different ways: one that clearly shows the physical invariance and the other that shows an apparent change of the causal structure. Finally we consider a new type of disformal transformation in which a multi-component scalar field comes into play, which we call a "multi-disformal transformation". We show that the curvature and tensor perturbations are invariant at linear order, and also at non-linear order provided that the system has reached the adiabatic limit.Comment: 8 page

Chapter 作品 『壁』における の表象 - 安 公房はその文学に をどう描いたか / Representation of food in the collection of works Kabe: How Abe Kōbō wrote about food in the literature

This paper aims to examine the way "food" is depicted in “Kabe (The Wall)” (1951) written by Abe Kōbō. “Kabe” is Abe's first collection of works, and it consists of three parts: “S.Karuma-shi no Hanzai (The Crime of S. Karma)” (1951), “Akai Mayu (The Red Cocoon)” (1950), and six other works. Based on discussions in previous studies, I first aimed to clarify where Abe's "consistent intention" in his "Postscript" can be found from the perspective of quantitative text analysis using KH Coder. Then, I chose "food" as one of the indicators to support the worldbuilding and the actions of the characters in the work. I pointed out that the variety of both food and drink is limited, also there are no significant descriptions of taste, and that it can be inferred that what people eat is divided according to their positions in the story. In “Kabe”, the description of "food" is used as a trigger for the characters to move on to the next action

A Global Sign-Logo Recognition System

In the paper, we present a sign-logo recognition system for detecting meanings of signs and logos existing in a global real space. First, this system finds out the category of a sign-logo image input to the system by the similarity computations with images in the database focusing on the color and shape features of images. Second, the system searches for the information corresponding to the specific sign-logo image. This system makes it possible for a user to find out the meaning and the related information of sign-logos based on the user’s location. This paper also presents several experimental results for sign-logo recognition functions by using actual sign-logo images. Those results clarify the feasibility and the applicability of our system in real world spaces

HiGate (High Grade Anti-Tamper Equipment) Prototype and Application to e-Discovery

These days, most data is digitized and processed in various ways by computers. In the past, computer owners were free to process data as desired and to observe the inputted data as well as the interim results. However, the unrestricted processing of data and accessing of interim results even by computer users is associated with an increasing number of adverse events. These adverse events often occur when sensitive data such as personal or confidential business information must be handled by two or more parties, such as in the case of e-Discovery, used in legal proceedings, or epidemiologic studies. To solve this problem, providers encrypt data, and the owner of the computer performs decoding in the memory for encrypted data. The computer owner can be limited to performing only certain processing of data and to observing only the final results. As an implementation that uses existing technology to realize this solution, the processing of data contained in a smart card was considered, but such an implementation would not be practical due to issues related to computer capacity and processing speed. Accordingly, the authors present the concept of PC-based High Grade AntiTamper Equipment (HiGATE), which allows data to be handled without revealing the data content to administrators or users. To verify this concept, an eDiscovery application on a prototype was executed and the results are reported here