Computer mice and keyboards are most widely used to work with personal computers as pointing and typing devices respectively. As alternatives to a computer mouse, there are other types of pointing devices that use depth sensor or camera for pointing detection. However, current implementations are uncomfortable for usage because a user must raise his arm(s) to control pointing, as well as having a relatively long distance from the sensing device. To solve those usability problems, we propose a pointing device that can narrow the distance within which users can comfortably move their wrists between the keyboard and the pointing device itself. For this system, we compared between various depth sensors' performance and eventually chose the Intel Realsense sensor for our system's use. Additionally, we performed a comparative study involving our proposed system's performance and that of other conventional input devices. Although the total time to complete experimental tasks using our system was longer than by using other conventional input devices, our proposed system has the fastest time when switching between pointing and typing (i.e. moving hand from mouse to keyboard).

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The clinical characteristics of perimesencephalic nonaneurysmal subarachnoid hemorrhage (SAH) caused by physical exertion were analyzed to investigate the causes and mechanisms of perimesencephalic nonaneurysmal SAH. Nine of 209 patients with spontaneous SAH were identified as having perimesencephalic nonaneurysmal SAH. Perimesencephalic nonaneurysmal SAH in four males and three females was precipitated by exertion. Age, sex predominance, type of exertion, symptoms, loss of consciousness during bleeding, clinical grade, angiographic spasm, hydrocephalus, delayed ischemic deficit, rebleeding, hypertension, and outcome were evaluated in these seven patients. Outcomes were assessed using the Glasgow Outcome Scale. Patients showed male predominance (57.1%), relatively young age (mean 50 years), low frequency of hypertension (28.6%), good clinical grade (World Federation of Neurological Surgeons grade I or II), and excellent outcomes including no rebleeding, no symptomatic hydrocephalus, and no delayed ischemic deficits. The type of exertion was swimming in two patients, golfing in two patients, heavy lifting in two patients, and bending forward during gymnastics in one patient. Physical exertion including components of the Valsalva maneuver is an important predisposing factor for perimesencephalic nonaneurysmal SAH. Such physical exertion produces increased intrathoracic pressure, which blocks the internal jugular venous return, resulting in elevated intracranial venous pressure or mechanical swelling of the intracranial veins, and leads to venous or capillary breakdown.

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Ballasted track is widely as a main track structure and requires regular maintenance because track geometry deteriorates under the influence of dynamic loads. Therefore, several pieces of research into prediction and prevention of ballasted track deterioration, and maintenance of deteriorated ballasted track have been conducted by RTRI or other organizations around the world. This paper introduces some of the results obtained from the recent research into ballasted track carried out by RTRI and suggests possible future developments in this field.

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The wafer level packaging process is useful for mass production of micro electro-mechanical system (MEMS) devices. The process includes anodic bonding of a glass cap wafer with cavities to a silicon wafer mounting multiple devices. Although etching and abrasive blasting are commonly used to form cavities on the cap wafer, these methods are not efficient and are harmful to the environment because they use etching chemicals or blasting abrasives. Therefore, we propose a new method in which a cap wafer with box-shape cavities are prepared by hot embossing with a block-patterned mold and surface grinding after hot embossing. Examination of MEMS devices packaged with the cap wafer prepared by the proposed method indicated that this method makes it possible to package the devices with a leak rate of 3.8×10^-9Pa m³/s.

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The improvement rate of countermeasures adopted in constructing a second track on an embankment on soft ground is determined empirically due to unknown factors such as the deformation properties of soft ground. In this study, centrifuge model tests were performed to grasp the deformation properties of soft ground for such construction cases. Based on the test result, a new countermeasure was proposed, which has high horizontal support performance and combines deep mixing wall-type ground improvements and cement-mixed gravel. The proposed method having the same improvement rate as deep mixing was confirmed as being able to reduce the deformation of the embankment and the surrounding ground.

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Spinal dural arteriovenous fistulas (SDAVFs) are rare vascular malformations that can occur anywhere in the spine. Most SDAVFs lead to slow aggressive myelopathy due to venous congestion at a level adjacent to the shunt point. However, rare cases of localized brainstem edema without spinal cord lesions have been reported. In this study, we present a case of a lower cervical SDAVF that showed localized congestive edema of the medulla in the absence of an edematous change in the cervical spinal cord. The patient was a 57-year-old woman who experienced vertigo and vomiting without myelopathy that did not improve with conservative treatment. Magnetic resonance imaging (MRI) revealed high signal intensity in the left medulla on T2-weighted imaging (T2WI), while angiography revealed an SDAVF at the right C8 segmental level supplied by the right thyrocervical trunk. She underwent surgical interruption of the draining vein, which led to a rapid improvement in her symptoms. A subsequent follow-up MRI confirmed resolution of both the medullary edema and the dilated draining vein. SDAVFs may cause vertigo and vomiting, which are brainstem symptoms. Early diagnosis and surgical intervention are crucial for successful treatment outcomes.

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The three-dimensional aerial holographic image interface (3DAHII) is a system for aerial projection of varying 3D objects. The projected objects can be viewed from multiple directions without the use of special devices such as eyeglasses, gas or vapor for projection, rotating parts, and so on. In this research, we propose a system to capture a video of a human body from different perspectives in real-time, and project the result using 3DAHII. Because of realtime capturing and projection, users can interact and communicate directly. To realize this goal, we used a smaller prototype system in which four cameras capture a video of a physical object inside a frame, and the video result will be remotely projected in real-time. The smaller prototype is developed for evaluation and confirmation of the proposed system's operation.

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This paper presents a newly developed calligraphy-stroke learning support system. The system incorporates the following functions: a) Displaying brushwork, trajectory, and handwriting; b) recording and playback of an expert’s calligraphy-stroke; and c) teaching a learner a calligraphy-stroke. The following features of the system demonstrate the contributions of our study. (1) The system, which consists of a sensor and projector, is simple and compact, so as to be easily introduced to the usual educational fields and practical leaning situations. (2) Three-dimensional calligraphy-stroke is instructed by presenting two-dimensional visual information. (3) A trajectory region is generated in the form of continuous squares, calculated using a brush model based on the brush position information measured by a sensor. (4) Handwriting is expressed by mapping a handwriting texture image according to ink concentration and the brush handling state. The results of the trial experiment suggest the effectiveness of the learning support function in terms of letter form and calligraphy-stroke.

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