Takumi Kobayashi

Action and simultaneous multiple-person identification using cubic higher-order local auto-correlation

We propose a new method - cubic higher-order local auto-correlation (CHLAC) - to address three-way data analysis. This method is a natural extension of higher-order local auto-correlation (HLAC) (N. Otsu and T. Kurita, 1988), which deals only with two-way data. Both methods use correlation to summarize relative positions or motions within a local data region, and these can be calculated simply with a low computational load. Moreover, our new method (CHLAC) offers several preferable properties as well as HLAC: shift-invariance to data (rendering the method segmentation-free), additivity for data, and robustness to noise in data. In this study, we applied this method to action and simultaneous multiple-person identification from a motion-image sequence through the property of data additivity. Experimental results showed that this method performed well.

Buffer-gas cooling of antiprotonic helium to 1.5 to 1.7 K, and antiproton-to–electron mass ratio

Exotic molecule tests fundamental symmetry Spectroscopy of exotic molecules can offer insight into fundamental physics. Hori et al. studied the transition frequencies of an unusual helium atom in which one of the two electrons was substituted by an antiproton, the negatively charged antiparticle partner of the proton (see the Perspective by Ubachs). The antiprotonic helium was cooled down to low temperatures to allow the frequencies to be measured with high precision. The extracted mass of the antiproton (relative to the electron mass) was in good agreement with previous measurements of the proton mass. This finding is in keeping with the implications of the combined charge, parity, and time-reversal symmetry of physical laws. Science, this issue p. 610; see also p. 546 Spectroscopy of a cold exotic molecule yields a precise value of the antiproton mass relative to the mass of the electron. Charge, parity, and time reversal (CPT) symmetry implies that a particle and its antiparticle have the same mass. The antiproton-to-electron mass ratio Mp¯/me can be precisely determined from the single-photon transition frequencies of antiprotonic helium. We measured 13 such frequencies with laser spectroscopy to a fractional precision of 2.5 × 10−9 to 16 × 10−9. About 2 × 109 antiprotonic helium atoms were cooled to temperatures between 1.5 and 1.7 kelvin by using buffer-gas cooling in cryogenic low-pressure helium gas; the narrow thermal distribution led to the observation of sharp spectral lines of small thermal Doppler width. The deviation between the experimental frequencies and the results of three-body quantum electrodynamics calculations was reduced by a factor of 1.4 to 10 compared with previous single-photon experiments. From this, Mp¯/me was determined as 1836.1526734(15), which agrees with a recent proton-to-electron experimental value within 8 × 10−10.

Microwave spectroscopic study of the hyperfine structure of antiprotonic 3He

In this work, we describe the latest results for the measurements of the hyperfine structure of antiprotonic 3 He. Two out of four measurable super–super-hyperfine (SSHF) transition lines of the (n,L) = (36, 34) state of antiprotonic 3 He were observed. The measured frequencies of the individual transitions are 11.125 48(08) GHz and 11.157 93(13) GHz, with the increased precisions of about 43% and 25%, respectively, compared to our first measurements with antiprotonic 3 He (Friedreich et al 2011 Phys. Lett. B 700 1–6). They are less than 0.5 MHz higher with respect to the most recent theoretical values, still within their estimated errors. Although the experimental uncertainty for the difference of 0.032 45(15) GHz between these frequencies is large as compared to that of theory, its measured value also agrees with theoretical calculations. The rates for collisions between antiprotonic helium and helium atoms have been assessed through comparison with simulations, resulting in an elastic collision rate of γe = 3.41 ± 0.62 MHz and an inelastic collision rate of γi = 0.51 ± 0.07 MHz. (Some figures may appear in colour only in the online journal)

Recognition of Dynamic Texture Patterns Using CHLAC Features

In this paper, we propose a statistical scheme for recognizing three-dimensional textures shown in motion images, which we call dynamic textures. The texture characteristics emerges in the distinct movement in the motion images, and the dynamic cues would be useful especially for recognizing ambiguous texture patterns in noisy images. We apply cubic higher-order auto-correlation (CHLAC) to extract features both of the textures and their movements, and then simply multiple regression analysis (MRA) to evaluate (recognize) the texture. In the experiment for estimating quality of beef meat by using ultrasound motion images, the proposed method exhibits the favorable performances which are close to ground truth given by the experts.

The Cow Gait Recognition Using CHLAC

This paper reports the preliminary experiments on the cow identification via gait recognition of motion images. The eight cows walking under two different situations have been precisely identified by Cubic Higher-order Local Auto-Correlation (CHLAC). The cow gait recognition using CHLAC is expected to be a landmark achievement for realizing cost-effective dairy cattle breeding management systems which do not use any sensors and hormone in order to determine the timing of artificial insemination in dairy cattle.

Development of Software for Real-Time Unusual Motions Detection by Using CHLAC

We developed software that automatically detects unusual motions in a video sequence in real-time by using an efficient implementation of CHLAC and a visual software framework called Lavatube. Video monitoring systems that can automatically detect unusual motions are currently in great demand. CHLAC has been shown to work effectively and favorably for this task. A newly developed parallel processing technique increases the speed of CHLAC by using SIMD instructions. The platform software Lavatube supports easy construction of a video processing system using graph-connecting icons on a GUI. We demonstrated the effectiveness of the proposed system through experiments in indoor and outdoor environments.

Toward a HLAC-Based Histological Diagnosis System for Virtual-Slide Images

We are developing an HLAC-based system to emulate pathologists skill for cancer diagnosis. The system very quickly processes virtual-slide images of tissues under high magnification, and automatically diagnoses cancer by anomaly detection based on HLAC and PCA. We have demonstrated the effectiveness of this system through experiments on actual cases of metastasized cancers in lymph nodes.

A variant at 9q34.11 is associated with HLA-DQB1*06:02 negative essential hypersomnia

Essential hypersomnia (EHS) is a lifelong disorder characterized by excessive daytime sleepiness without cataplexy. EHS is associated with human leukocyte antigen (HLA)-DQB1*06:02, similar to narcolepsy with cataplexy (narcolepsy). Previous studies suggest that DQB1*06:02-positive and -negative EHS are different in terms of their clinical features and follow different pathological pathways. DQB1*06:02-positive EHS and narcolepsy share the same susceptibility genes. In the present study, we report a genome-wide association study with replication for DQB1*06:02-negative EHS (408 patients and 2247 healthy controls, all Japanese). One single-nucleotide polymorphism, rs10988217, which is located 15-kb upstream of carnitine O-acetyltransferase (CRAT), was significantly associated with DQB1*06:02-negative EHS (Pu2009=u20097.5u2009×u200910−9, odds ratiou2009=u20092.63). The risk allele of the disease-associated SNP was correlated with higher expression levels of CRAT in various tissues and cell types, including brain tissue. In addition, the risk allele was associated with levels of succinylcarnitine (Pu2009=u20091.4u2009×u200910−18) in human blood. The leading SNP in this region was the same in associations with both DQB1*06:02-negative EHS and succinylcarnitine levels. The results suggest that DQB1*06:02-negative EHS may be associated with an underlying dysfunction in energy metabolic pathways.

Beam diagnostics for measurements of in-flight annihilation cross sections of antiprotons at 130 keV

Hossein Aghai-Khozani1,2, Daniel Barna3,4, Maurizio Corradini5,6, Ryugo Hayano4, Masaki Hori1,4, Takumi Kobayashi4, Marco Leali5,6, Evandro Lodi-Rizzini5,6, Valerio Mascagna5,6, Michela Prest7,8, Anna Soter1, Koichi Todoroki4, Erik Vallazza9, Luca Venturelli5,6, and Nicola Zurlo5,6 1Max-Planck-Institut fur Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching, Germany 2Physics Department, CERN, 1211 Geneva 23, Switzerland 3Wigner Institute for Particle and Nuclear Physics, H-1525 Budapest, Hungary 4Department of Physics, University of Tokyo, Hongo7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan 5Dipartimento di Collegato di Brescia, 25133 Brescia, Italy 6INFN, Gruppo Collegato di Brescia, 25133 Brescia, Italy 7Dipartimento di Scienze Fisiche e Matematiche, Universita di Como, I-22100 Como, Italy 8INFN, Sezione di Milano Bicocca, I-20126 Milano, Italy 9INFN, Sezione di Trieste, I-34127 Trieste, Italy

Segmented scintillators with SiPM readout for measuring antiproton annihilations

The Atomic Spectroscopy and Collisions Using Slow Antiprotons (ASACUSA) experiment at CERN constructed some segmented scintillation counters to measure and track the charged pions emerging from antiproton annihilations in a future superconducting radiofrequency Paul trap for antiprotons. The photoelectron yields of various scintillator configurations were measured using a p beam of momentum p 1 GeV/c at the T9 beamline of the CERN Proton Synchrotron (PS). Various fibers and silicon photomultipliers, fiber end terminations, and couplings between the fibers and scintillators were compared. The detectors were also tested using the antiproton beam of the Antiproton Decelerator (AD). At high antiproton rates a saturation was observed in the scintillator signal. We review the detector construction and measurement results.