Network-Based Continuous Space Representation for Describing Pedestrian Movement in High Resolution

A concept of network-based continuous space representation is proposed and applied to the sequential map matching problem with simulation data assuming pedestrian movement. The concept allows for dealing with situations that the resolution of network representation is not high enough to describe the pedestrian movement considering the observation accuracy. The experiment showed that the proposed concept worked well in the example of pedestrian movement along with the sidewalk by estimation of accurate positions

Deep Adversarial Reinforcement Learning With Noise Compensation by Autoencoder

We present a new adversarial learning method for deep reinforcement learning (DRL). Based on this method, robust internal representation in a deep Q-network (DQN) was introduced by applying adversarial noise to disturb the DQN policy; however, it was compensated for by the autoencoder network. In particular, we proposed the use of a new type of adversarial noise: it encourages the policy to choose the worst action leading to the worst outcome at each state. When the proposed method, called deep Q-W-network regularized with an autoencoder (DQWAE), was applied to seven different games in an Atari 2600, the results were convincing. DQWAE exhibited greater robustness against the random/adversarial noise added to the input and accelerated the learning process more than the baseline DQN. When applied to a realistic automatic driving simulation, the proposed DRL method was found to be effective at rendering the acquired policy robust against random/adversarial noise

Human Tracking by Integrating Simulation Model and Observation Data

学位の種別:課程博士University of Tokyo(東京大学

トラッキングデータを用いたサッカーの試合における戦況変化の抽出

要旨ありスポーツ統計科学の新たな挑戦研究ノー

Traffic count data analysis using mixtures of Kato–Jones distributions

We discuss the modelling of traffic count data that show the variation of traffic volume within a day. For the modelling, we apply mixtures of Kato–Jones distributions in which each component is unimodal and affords a wide range of skewness and kurtosis. We consider two methods for parameter estimation, namely, a modified method of moments and the maximum-likelihood method. These methods were seen to be useful for fitting the proposed mixtures to our data. As a result, the variation in traffic volume was classified into the morning and evening traffic whose distributions have different shapes, particularly different degrees of skewness and kurtosis

口腔内所見を用いた新たな年齢推定法

In forensic science, age estimation is an important step in identifying unidentified cadavers. As teeth are resistant to environmental degradation for long periods of time, they are often used to estimate age. Although there have been many reports of age estimation based on dental morphology, these methods tend to be subjective and cannot be used i n the case of edentulous jaws. In the present study, we developed a new method of age estimation from dental parameters (number of upper teeth [UT], lower teeth [LT], and prostheses [NP]; tooth attrition [TA]; and occlusal area [OA]) and the mandibular angle (MA) measured at proposed an equation for calculating the age. The results show that the mean error of this method is similar to that of previous methods, and even demonstrated improved accuracy in subjects aged >60 years. We also proposed an equation for age estimation from only the MA, and showed that we can perform age estimation even in edentulous cases using this equation. Because our method is superior in its simplicity, objectivity, and applicability when compared with previous methods, we believe our method wll prove useful for age estimation in a wide variety of cases.博士（医学）・甲611号・平成26年3月17

Calcium Phosphate Composition Affects Ureteroscopic Laser Lithotripsy

The effects of stone composition on transurethral lithotripsy (TUL) have not been sufficiently elucidated. The purpose of this study was to identify how calcium phosphate stone composition impacts TUL. Two hundred eighty-nine cases of semi-rigid and/or flexible TUL for upper urinary tract calculi were reviewed retrospectively. Inclusion criteria were a preoperative assessment by noncontrast computed tomography (NCCT) and a stone composition analysis. Small stones and those without calcium composition were excluded. Stone core radiodensity (SCR) was measured by taking the average of the upper 3 of 5 points in the proximity of the center of the stone on NCCT. Fifty-three patients with calcium phosphate composition (CaP) and 118 patients with calcium oxalate and without phosphate composition were eligible for analysis. SCR was significantly higher in the CaP group (p<0.01). The CaP patient group needed a significantly longer operation time (p=0.014) and more laser energy (p=0.085), and tended to have a lower rate of complete lithotripsy (p=0.096) and higher incidence of postoperative pyelonephritis (p=0.181). Stones containing calcium phosphate are harder, demand more laser energy, and require a longer operating time. NCCT evaluation can estimate stone composition preoperatively, and may be a useful tool for predicting operative outcomes