Given huge collections of time-evolving events such as web-click logs, medical records, which consist of multiple attributes, how do we find patterns and trends? How do we go about capturing typical patterns and forecasting future events? We introduce TriMine, which has two properties: (a) effectiveness, that is, the patterns help us understand the data, discover groups, and enable forecasting, and (b) scalability, that is, our method is linear with the data size. Extensive experiments on real datasets demonstrate that our methods discover meaningful patterns and makes long-range forecasts, which are notoriously difficult to achieve. In fact, our methods consistently outperform the best state-of-the-art existing methods in terms of accuracy and execution speed.

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Intraoral radiograph, panoramic radiograph, and cone beam CT (CBCT) are most important imaging modalities in dentistry. The development of arm-type CBCT has paved the way for the general dentist to own CT. Moreover, clinical application of surgical simulation and navigation system with 3D CT imaging is getting popular.
However in compare with medical whole-body CT, dental CBCT has several disadvantages in the accuracy of CT value. These are projection data discontinuity related artifact, x-ray beam hardening phenomenon, halation of x-ray detector, scattered x-ray and so on.
The highly sensitive photon-counting x-ray detector will provide new functions to panoramic radiography, such as the tomosynthesis technique and energy quantitative radiography. Tomosynthesis imaging enables clear depiction of teeth without blurry. This image may take place of intraoral radiograph. Energy quantitation may enable the image-based quantity and quality analysis of hard tissue anatomy and/or restorative dental materials in vivo. In addition, coordinating application of computer-aided detection/diagnosis (CAD) and teleradiology will enhance the diagnostic capabilities of dental practitioners.

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When an x-ray penetrates though the material, the phase of the x-ray shifts in addition to the absorption of the x-ray. It's known that the shifts of the phase have higher sensitivity to the soft tissues than conventional one. But it was difficult to apply the imaging of phase shift to medical fields because the system needs a coherent x-ray source such as a synchrotron light source and a micro-focus x-ray tube. An x-ray Talbot-Lau interferometry is one of the phase-contrast imaging methods, which works with a conventional x-ray tube. We developed experimental systems and carried out the experiments to depict the soft tissues with the approvals of the ethic committees. These results were confirmed by comparison of dissections and specimen of organs. After confirmation, we developed another system for clinical evaluation to depict the joints in limbs and imaging tests on healthy volunteers were carried out. We confirmed that the surface of the cartilage was clearly depicted with in vivo imaging. It is assumed that cartilage deforms before the deformation of a joint in a patient of rheumatoid arthritis and osteoarthritis. This system is expected to contribute to detect these diseases as precursors of the distraction of the joints by detecting the deformation of the cartilage. Also it is expected to detect lesions of the breast cancer in earlier stage by its high sensitivity. We elaborate to make the system available in the clinical use near future.

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