In this paper, we develop a

called YYZVis, which can efficiently handle a new overset grid in a sphere composed of Yin, Yang, and Zhong grids. Conventionally, in order to visualize the overset grid dataset, it must be merged into a single uniform structured volume. However, this merging process may increase memory and time complexities, and some artifacts may occur owing to interpolation errors around the boundaries of the sphere. In YYZVis, the Yin-Yang-Zhong (YYZ) grid dataset can be visualized without any grid merging process. YYZVis provides basic visualization functionalities such as isosurfaces, slice planes, and volume rendering, as modules comprise the visualization pipeline. Therefore, YYZVis allows us to efficiently develop a visualization system by combining our proposed modules with existing modules. In the experiments, we applied YYZVis to a magnetohydrodynamics simulation result and confirmed its effectiveness.

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様々な言語活動を行っている時の脳の活動部位を特定する有力な方法として, 脳血流をPET (positron emission tomography) で計測しSPM (Statistical Parametric Mapping) で解析する手法がある. SPMは脳全体にわたって有意な活動部位を検出する優れた解析方法である. しかし, 従来これらの表示方法は平面スライス, 3方向投影図, 脳表面着色図がほとんどで, これらでは立体的位置関係が分かりにくく読影が困難であった. そこで今回我々は脳機能画像をより分かり易く読影できるよう, これらを3次元再構築した画像作成を試みた.
対象は正常ボランティア12名で, 日常会話文聴取時のPET画像をSPMで解析した後, 1) SPM付属の従来の表示, 2) 3次元静止画像, 3) 3次元動画の作成を試みた. 2), 3) の3次元表示にはVTK (The ) のvolume rendering機能を使用したのが特徴である. また, 脳機能画像には元の脳画像が含まれないため, MRI脳画像との合成などを自作C++プログラムによって行った. 3) の動画は2) の静止画で一コマーコマを作成し, 市販ソフトウエアを用いて動画にした. 2), 3) の画像作成はパソコンを用いて行った.
この結果, 従来の表示方法に比べ, 3次元再構築を行うことで脳活動部位の同定がより容易となった.
脳機能画像は従来神経内科, 脳外科などの領分であったが, 耳鼻咽喉科でも言語の聴取, 表出を扱っている点から今後ますます重要な領域になると考えられる. 今回のように, 従来分かりにくかった脳機能画像を正確な3次元表示画像にすることが, 脳機能画像を正確で直感的に読影するのに重要であり, ひいてはこの分野での発展につながると考えられた. また, 3次元表示で一般的に知られている手法はsurface modelであるが, 脳のようなものの表示には今回用いたvolume renderingの方が優れていると考えられた.

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Multipurpose AVS/Express provides visualization function as an object called "module" and user can change visualization parameters (e.g. level of isosuface, slice axis and plain) interactively. However in VR environment (e.g. CAVE), It is difficult for observer to change visualization parameters. We improve the user interface to change visualization parameters using simple menu on PDA within the CAVE environment. Using the PDA device, users can easily change visualization parameters in VR environment.

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A 3D visualization of argon and nitrogen-argon plasma electron density (n_e) and effective temperature (T_eff) distributions were constructed using the I-V curves from Langmuir probe traces at specific discrete positions in the extraction region of a magnetized sheet plasma ion source. Argon and mixed N₂-Ar sheet plasmas are characterized using the calculation of the electron energy distribution function (EEDF). By taking the current vs. voltage reading of a single probe in 68 discrete locations of the plasma, a 3-dimensional map of the electron density and electron temperature were constructed. The map was constructed to understand the global condition of the extraction region of the source. The technique can be applied to the determination and understanding of edge plasma parameters in magnetic confinement devices.

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Recently, digitalization of medical image went rapidly, and the images are used at clinical fields. However, as a result, doctors must treat a large quantity of medical images at a time, and make burdens to radiologists. In order to reduce their burdens, it is common to introduce CAD (Computer-Aided Diagnosis) system to support diagnostic imaging. But the general CAD system is very expensive, and it is quite hard to treat it for medical practitioners. The aim of this study to investigate functions desired for CAD system and develop cheap and simple one by cooperating 'with the hospital side.

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Thermal display, which is a type of haptic display, is effective in providing intuitive information of temperature. However, in many studies, the user has assumed a sitting position during the use of these devices. In contrast, the user generally watches 3D objects while standing and walking around in large-scale virtual reality system, In addition, in scientific visualization, the response time is very important for observing physical phenomena, especially for dynamic numerical simulation. One solution is to provide two types of thermal information: information about the rate of thermal change and information about the actual temperature. We propose a thermal display with two Peltier elements which can show above two pairs of information and the result (for example energy and temperature, as thermal information) of numerical simulation. Finally, we represent an example of visualizing and haptizing the result of molecular dynamics simulation.

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Multipurpose AVS/Express provides visualization function as an object called "module", but it has been developed for single processor. So in the case of dealing large data, it takes very long time and requires large machine resource. To solve the problems, we add parallel processing function to AVS/Express. This is called AVS/Express PST, which has functions as follows.
a) Dividing and distributing data and processing distributed data on each node, b) Parallel processing, c)Parallel rendering d) API for developing parallel module These functions are effective in visualization of large data.

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We developed a virtual reality visualization program, Digital-LHD, for modern Head-Mounted Display (HMD) systems. Digital-LHD provides an immersive environment for the interactive visualization of plasma data related to the Large Helical Device (LHD). Its predecessor, Virtual-LHD, was developed for CAVE systems, which were limited in accessibility due to their cost and size. The newly developed Digital-LHD utilizes Unity and C# to offer interactive 3D visualization. Digital-LHD includes features such as isosurface rendering, magnetic field line tracing, particle trajectory visualization, and new functionalities like local arrow glyphs and a plasma pressure color contour. The enhanced interactivity and intuitive GUI have improved the user experience. Digital-LHD enables fusion plasma researchers to perform immersive visualizations with HMDs, providing a more accessible and cost-effective solution.

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The Geant4 is a Monte Carlo simulation toolkit employed for reliable dose calculations in medical physics. However, Geant4 requires C++ user-code developments according to the simulation purposes. Therefore, it is not easy to apply Geant4 for medical physics research, especially for Geant4 beginners. To facilitate the use of Geant4, we have developed Galet-Med, an Geant4 based application templet software for medical physics, by referencing on the simulation codes of PTSIM (Geant4 based Particle Therapy Simulation Framework) that were developed particularly for particle therapy facilities. The Galet-Med is intended for laboratory research, providing interfaces for description of material, geometry, and scoring for minimizing coding efforts while maintaining C++ implementation compatibility. For example, the geometries are imported in a voxelated

format, and the geometry description markup language format, as well as from C++ coded descriptions. This paper presents the use of Galet-Med for several use-cases in medical physics applications.

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In this paper, we propose a visualization development framework that is a C++ class library for easily and efficiently rendering three-dimensional datasets, such as numerical simulation results, medical image datasets, and measurement datasets. Our framework provides a modular programming environment that supports the construction and execution of a visualization pipeline and allows the user to readily implement custom visualization algorithms using our simple module-based execution model. In addition, we also provide a simple implementation of a visualization environment that can handle multiple volumes and semi-transparent polygons in a single scene, which we call a fused visualization environment. Although many visualization software packages have been proposed thus far, such an environment has not previously been supported because of the visibility ordering problem. To confirm the effectiveness of our proposed visualization framework, we demonstrate several visualization applications implemented using this framework.

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Purpose: To compare the precision of maxillo-mandibular registration and resulting full arch occlusion produced by three intraoral scanners in vitro.

Methods: Six dental models (groups A-F) were scanned five times with intraoral scanners (CEREC, TRIOS, PLANMECA), producing both full arch and two buccal maxillo-mandibular scans. Total surface area of contact points (defined as regions within 0.1 mm and all mesh penetrations) was measured, and the distances between four pairs of key points were compared, each two in the posterior and anterior.

Results: Total surface area of contact points varied significantly among scanners across all groups. CEREC produced the smallest contact surface areas (5.7-25.3 mm²), while PLANMECA tended to produce the largest areas in each group (22.2-60.2 mm²). Precision of scanners, as measured by the 95% CI range, varied from 0.1-0.9 mm for posterior key points. For anterior key points the 95% CI range was smaller, particularly when multiple posterior teeth were still present (0.04-0.42 mm). With progressive loss of posterior units (groups D-F), differences in the anterior occlusion among scanners became significant in five out of six groups (D-F left canines and D, F right canines, p < 0.05).

Conclusions: Maxillo-mandibular registrations from three intraoral scanners created significantly different surface areas of occlusal contact. Posterior occlusions revealed lower precision for all scanners than anterior. CEREC tended towards incorrect posterior open bites, whilst TRIOS was most consistent in reproducing occluding units.

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Industrial reforms utilizing artificial intelligence (AI) have been progressing remarkably worldwide in recent years. In medical informatics, medical big-data analytics involving AI are increasingly being promoted, and AI in the medical field is being widely applied in research areas such as protein-structure analysis and diagnostic support. Previously, we developed a unique adverse drug reactions analysis system that incorporates Accord.NET, an open-source machine learning (ML) framework written in the programming language C#, and uses the Japanese Adverse Drug Event Report (JADER) database. The developed system can provide necessary information for exploratory investigation of drug efficacy, side effects, adherence, and so on. To efficiently interpret the calculated data and minimize noise, the developed system features a data visualization tool that can visualize the results of various statistical analyses and machine learning models in real-time three dimensions (3D), making it intuitive to grasp the results. This feature makes the system ideal for individuals in clinical work. We believe that the system will facilitate more efficient drug management and clinical pharmacy research. In this review, we introduce an example of domain-driven design development of this AI analysis system for pharmacists in clinical practice with the aim of further utilizing medical big data and AI analytics.

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The micellar shape transition in amphiphilic solutions is studied by coarse-grained molecular dynamics simulations of rigid amphiphilic molecules with explicit solvent molecules. Our simulations show that the dominant micellar shape changes from disc to cylinder, and then to sphere as the hydrophilic interaction increases. We find that, as the hydrophilic interaction increases, the potential energy decreases monotonically even during the micellar shape transition, whereas the slope of the potential energy decreases in a stepwise manner in relation to the micellar shape transition. We also ascertained that there exists a wide coexistence region in the intensity of the hydrophilic interaction between a cylinder and a sphere, whereas the coexistence region between a cylinder and a disc is very narrow.

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Since the year of 1977, the world of medical diagnosis has entered a new era with the invention of the modern magnetic resonance imaging (MRI) scanners. These scanners can produce high quality images of any part of the human body. MRI techniques are the method of choice in the diagnosis of tumors, and malformations of the brain because of the incredible ability of distinguishing between the different tissue types, and therefore providing valuable information about the problem at hand. In this thesis a method of segmenting an MRI data set of the brain and providing a 3D model of the white matter, the gray matter and the CSF is introduced. This method consists of three major steps: Skull Stripping, Tissue Classification and Volume rendering. The skull stripping method uses an anisotropic diffusion filter for noise removal, Marr-Helder edge detector to isolate anatomical boundries and a set of morphological functions to remove the skull from the data set. The extraction of different tissue types is then carried out according to the different signals each tissue type produces during the MRI process. This method is based on thresholding, and extracts all the pixels of the desired tissue type that fall within a specified interval. For the volume visualization of the results of the segmentation many procedures exist nowadays. This thesis uses the , which is probably the most used one in the field of medical imaging. VTK provides the user with many libraries that could be used to suit the data type in question. For perfect visualization to be achieved, suitable functions had to be called and appropriate variables had to be set properly. Three accurate 3-D models of white matter, gray matter and cerebrospinal fluid were realized in this thesis according to the method described above.

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In this paper, we describe a fast practical method for surface modification of geometric objects defined by polygonal meshes. A space-mapping technique is used to transform a given or damaged part of a surface into a different shape in a continuous manner. We consider shape transformation as a general type of operation for surface modification, and attempt to approach the problem from a single point of view, namely, that of the space-mapping technique. Experimental results are included to demonstrate the functionality of our mesh-modeling toolkit.

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The National Institutes of Health (NIH) implemented a policy on data sharing in 2003. The policy reaffirmed the principle that data should be made as widely and freely available as possible while safeguarding the privacy of research participants, and protecting confidential and proprietary data. Restricted availability of unique resources upon which further studies are dependent can impede the advancement of research and the delivery of medical care. Therefore, research data supported with NIH funds should be made readily available for research purposes to qualified individuals within the scientific community.

One approach to sharing data is to establish a network of databases. However, there are a number of barriers to creating successful networks, which can include fundamental differences in informatics infrastructure and communication tools used at various research sites. Solutions will entail standards for data collection, processing, and archiving to allow interoperability among the databases and the ability to query data across databases. Open architectures for data collection as well as software to facilitate communication across different databases are needed.

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