To design intelligent and flexible computer interfaces the present paper develops models of a user which aim at guessing intention behind actions of the user. There are two types of user models : rule-based models and connectionist models. The author chooses the latter here, because they have various advantages over traditional rule-based models. Basic mechanism of the connectionist models being multiple constraint satisfaction, they go well with the requirement for guessing the intention of the user based on fragmentary information from various sources. Another advantage of the connectionist models is their flexibillty in learning and generalization. Developed in the paper are two kinds of connectionist user models. One is a model for typing error corrections of

commands. The other is a group of models for extracting features from a sequence of commands. Various kinds of typing errors can be categorized into two : temporal and spatial errors. Representing these two kinds of typing errors on a network is the key to modelling the error correction problem. To represent the temporal ambiguities in typing a coarse coded layer and cross links between this layer and an input layer are employed. To represent the spatial ambiguities in typing special coding scheme is used for representing characters in a command : Hamming distance between a pair of characters be the same as the spatial distance between the corresponding pair of keys on a keyboard. Many pairs of erroneous and corrected commands are given to an input and output layers of the network as training patterns. It turns out that error correction capability of this model is not so good for short commands due to insufficient clue to restoration. To improve its performance this model assimilates other sources of information. The first one is the contextual information : history of commands and statistical features of the sequence. This, however, does not work satisfactorily due to large variation of statistical features even within the same user. The second source of information is the typing error characteristics of the user : frequency of each kind of typing errors. This information contributes to the restoration of erroneous typed commands. For extracting features from a sequence of commands, a model for obtaining command occurrence probabilities and models for command transition probabilities are developed using the so-called buffer model. These models are expected to suggest users candidates of useful macro commands. Much remains for further study, but the performance of the proposed connectionist models demonstrates their potential effectiveness in the user interfaces.

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The DNS query traffic in a campus top domain DNS server were statistically investigated in order to find out the security incidents, especially bot worm (BW)-infected PCs on the campus network. The interesting results are obtained: (1) The total traffic of the DNS query access from the outside of the campus network frequently correlates with that of the number of their unique source IP addresses. (2) The unique source IP address-based entropy (randomness) also frequently correlates well with the query contents-based one. Therefore, these results indicate that we can detect suspicious IP hosts, especially, spam bots in the campus network by only watching DNS query traffic from the outside of the university.

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The hardware chosen for fMRI data analysis may depend on the platform already present in the laboratory or the supporting software. In this study, we ran SPM99 software on multiple platforms to examine whether we could analyze fMRI data by SPM99, and to compare their differences and limitations in processing fMRI data, which can be attributed to hardware capabilities. Six normal right-handed volunteers participated in a study of hand-grasping to obtain fMRI data. Each subject performed a run that consisted of 98 images. The run was measured using a gradient echo-type echo planar imaging sequence on a 1.5T apparatus with a head coil. We used several personal computer (PC), and Linux machines to analyze the fMRI data. There were no differences in the results obtained on several PC, and Linux machines. The only limitations in processing large amounts of the fMRI data were found using PC machines. This suggests that the results obtained with different machines were not affected by differences in hardware components, such as the CPU, memory and hard drive. Rather, it is likely that the limitations in analyzing a huge amount of the fMRI data were due to differences in the operating system (OS).

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本稿では，横浜国立大学附属図書館における図書管理システム（図書の選書・発注・受入から目録・OPACの提供までに至る一連のシステム）の過去と現状の分析を行い，問題点を摘出する。その上で，学術情報センターが運用を開始した新目録所在情報システムヘの対応も含めて，次期システムヘの課題を提示し，各大学図書館の今後のシステム導入にあたっても参考にできる話題を提供したい。

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Auditory artifacts due to switching head-related transfer functions (HRTFs) are investigated, using a software-implemented dynamic virtual auditory display (DVAD) developed by the authors. The DVAD responds to a listener's head rotation using a head-tracking device and switching HRTFs to present a highly realistic 3D virtual auditory space to the listener. The DVAD operates on Windows XP and does not require high-performance computers. A total system latency (TSL), which is the delay between head motion and the corresponding change of the ear input signal, is a significant factor of DVADs. The measured TSL of our DVAD is about 50ms, which is sufficient for practical applications and localization experiments. Another matter of concern is the auditory artifact in DVADs caused by switching HRTFs. Switching HRTFs gives rise to wave discontinuity of synthesized binaural signals, which can be perceived as click noises that degrade the quality of presented sound image. A subjective test and excitation patterns (EPNs) analysis using an auditory filter are performed with various source signals and HRTF spatial resolutions. The results of the subjective test reveal that click noise perception depends on the source signal and the HRTF spatial resolution. Furthermore, EPN analysis reveals that switching HRTFs significantly distorts the EPNs at the off signal frequencies. Such distortions, however, are masked perceptually by broad-bandwidth source signals, whereas they are not masked by narrow-bandwidth source signals, thereby making the click noise more detectable. A higher HRTF spatial resolution leads to smaller distortions. But, depending on the source signal, perceivable click noises still remain even with 0.5-degree spatial resolution, which is less than minimum audible angle (1 degree in front).

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明治大学図書館は，国際協力事業の一環として，韓国にある私立大学の一研究所の図書館づくりを支援した。翰林（ハンリン）大学校日本学研究所（池明観所長）日本語図書約3万冊を，わが国の国立情報学研究所目録所在情報サービス（NACSIS-

）を利用して整理するためのシステム構築，目録作成指導，図書館づくり指導等について，支援活動を行ってきた。本稿では，これら指導・支援に対する図書館としての考え方，システム化過程，図書整理システムの概要，図書の整理方針の策定と整理方法及びNACSIS-入力の為の要員養成過程などについて報告する。

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We describe the current status of CATS (astrophysical CATalogs Support system), a publicly accessible tool maintained at Special Astrophysical Observatory of the Russian Academy of Sciences (SAO RAS) (http://cats.sao.ru) allowing one to search hundreds of catalogs of astronomical objects discovered all along the electromagnetic spectrum. Our emphasis is mainly on catalogs of radio continuum sources observed from 10 MHz to 245 GHz, and secondly on catalogs of objects such as radio and active stars, X-ray binaries, planetary nebulae, HII regions, supernova remnants, pulsars, nearby and radio galaxies, AGN and quasars. CATS also includes the catalogs from the largest extragalactic surveys with non-radio waves. In 2008 CATS comprised a total of about 109 records from over 400 catalogs in the radio, IR, optical and X-ray windows, including most source catalogs deriving from observations with the Russian radio telescope RATAN-600. CATS offers several search tools through different ways of access, e.g. via Web-interface and e-mail. Since its creation in 1997 CATS has managed about 105requests. Currently CATS is used by external users about 1500 times per day and since its opening to the public in 1997 has received about 4000 requests for its selection and matching tasks.

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The optical recording system with the computer aided experimental support system has been developed to investigate the animal auditory brain functions. The optical recording system with a 12×12 photodiode array as the image sensors has the spatial resolution about 26μm square and the time resolution about 70μs as the sampled-hold rate. The experimental support software system can afford to analyze the dynamical data using time series analysis in order to make a neural processing model from the observed spatio-temporal data. Some new experimental results on the neural dynamics in the guinea pig auditory cortex have been successfully obtained using this system.

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