Takahiro Yamasaki

This paper describes a method of readability assessment for web documents. Readability is the ease in which text can be read and understood. We hypothesize that the readability is determined whether a reader can easily grasp text structures. The impression and the complexity of text are significant factors. We extract the features about impression and complexity from a plain text and additional data such as HTML tags.<br>In order to compare effect of extracting features, we are assessing readability rank by machine learning. We conduct 5-fold cross validation for each domain, and calculate the root mean squared error between the actual rank and the estimated rank. The cross validation experiments confirm that the performance of our method is high measured. It shows effectiveness of extracting features about the impression and the complexity for readability assessment.

In this paper, we present and discuss a simple estimation method for the life expectancy of optical disks using resampling (bootstrap) statistical analysis in order to roughly estimate the lifetime of archival-grade disks. The performance of this method was examined experimentally using the Eyring acceleration test with four stress conditions. Results demonstrated the capability of this bootstrap analysis for estimating life expectancy compared with conventional statistical analysis using the Eyring acceleration test.

Recently, Schwartz and Etzion proposed several efficient code construction methods of two-dimensional linear codes capable of correcting a single arbitrary cluster of errors of size b. Some of their methods, however, impose the constraint that the degree m of GF (2(m)) must be even. In this correspondence, we investigate whether such Schwartz-Etzion's methods are applicable to the case in is odd. We provide necessary and sufficient conditions for the original Schwartz-Etzion's methods to be used for constructing two-dimensional cluster-error-correcting linear codes for odd m, and show that the methods are available extensively.

Bluetooth is best suited for an exhibition guidance system, because of its low-power consumption, enabling visitors to use their own mobile phones as browsing devices. High user mobility assumed in an exhibition hall needs an efficient handoff mechanism, which is required to establish connection to the most appropriate access point (AP) with minimized duration and maximized interval. This paper presents an efficient handoff method, by which a mobile device predicts its movement and connects to the most appropriate AP in the moving direction without inquiry. The prediction is based upon location estimation as well as view history. A visitor is considered to be in the location of an exhibit when he/she requests the exhibit's info. The simulation results show the proposed method outperforms the existing methods in data rate and active mode rate.

In this research, a pre-download method in the information service system using Bluetooth is proposed. The pre-download method is to determine the information to the visitor's mobile in advance by using the movement prediction of the visitor. By using this method, the visitor can browse the information smoothly.<br>This method is evaluated by simulation in various room-layouts and walking routes. More than 92% of requested contents are pre-downloaded in case the memory size is large enough to download. The prototype of the information service system installed the proposed method has been developed. By using this system, the effect of the method is confirmed.

Qualitative reasoning is one of the fault detection and diagnosis methods and is an effective way for complex systems. Especially, in the stochastic qualitative reasoning, the probabilistic process is used for state transition of the qualitative models with probabilities. In this paper, the stochastic qualitative reasoning is applied to a modelling method of human qualitative thinking process based on the instrumentation diagram and the control information in building air conditioning systems. However, several subjects remain to be solved for practical uses. This paper proposes real-time simulation using the stochastic qualitative reasoning as a way of practical uses for fault detection and diagnosis of VAV (Variable Air Volume) system that is one of air conditioning systems.

To develope the fault detection & diagnosis system of air-conditioning systems, is important to gather field data and analyze actual faults. We gathered measurement and set point data from almost all controllers of the air-conditioning systems of one large scale building. We prepared the graphs of collected data and checked them on the basis of control informations with the site engineer in charge. And, we classified the knowleges derived from these procedures into basic symptoms, condition of disease, countermeasure list and check flow diagram. These results will be very useful to establish an automatic inspection method by developing effective fault detecting and diagnostic algorism. We will re-evaluate these knowleges for the similar air-conditioning system of other buildings

The development of the fault detection and diagnosis (FDD) system of air-conditioning systems has started as one of IEA-Annex 25 activities. Recently, FDD-WG of the Society of Heating, Air-Conditioning and Sanitary Engineers of Japan and IEA-Annex 34 are holding the development of the FDD system. The stochastic qualitative reasoning (SQR) provides a modelling method of human qualitative thinking process based on the instrumentation diagram and the control information of air-conditioning systems. In this paper, the simulation process of real fault data using the SQR method is reported. In the near future, the SQR will implement the automatic method of fault detection to the computer applications.