• Journal of the Institute of Electronics and Information Engineers
• /
• v.53 no.12
• /
• pp.175-179
• /
• 2016

Recent advances in technology of medical image have made surgical simulation that is helpful to diagnosis, operation plan, or education. Improving and enhancing the medical imaging have led to the availability of high definition images and three-dimensional (3D) visualization, it allows a better understanding in the surgical and educational field. The Real human field of view is stereoscopic. Therefore, with just 2D images, stereoscopic reconstruction process through the surgeon's head, is necessary. To reduce these process, 3D images have been used. 3D images enhanced 3D visualization, it provides significantly shorter time for surgeon for judgment in complex situations. Based on 3D image data set, virtual medical simulations, such as virtual endoscopy, surgical planning, and real-time interaction, have become possible. This article describes principles and recent applications of newer imaging techniques and special attention is directed towards medical 3D reconstruction techniques. Recent advances in technology of CT, MR and other imaging modalities has resulted in exciting new solutions and possibilities of shoulder imaging. Especially, three-dimensional (3D) images derived from medical devices provides advanced information. This presentation describes the principles and potential applications of 3D imaging techniques, simulation and printing in shoulder and elbow practice.

• Journal of the HCI Society of Korea
• /
• v.1 no.1
• /
• pp.53-61
• /
• 2006

In this paper, we propose a novel method for 3D reconstruction of an indoor scene using a multi-view camera. Until now, numerous disparity estimation algorithms have been developed with their own pros and cons. Thus, we may be given various sorts of depth images. In this paper, we deal with the generation of a 3D surface using several 3D point clouds acquired from a generic multi-view camera. Firstly, a 3D point cloud is estimated based on spatio-temporal property of several 3D point clouds. Secondly, the evaluated 3D point clouds, acquired from two viewpoints, are projected onto the same image plane to find correspondences, and registration is conducted through minimizing errors. Finally, a surface is created by fine-tuning 3D coordinates of point clouds, acquired from several viewpoints. The proposed method reduces the computational complexity by searching for corresponding points in 2D image plane, and is carried out effectively even if the precision of 3D point cloud is relatively low by exploiting the correlation with the neighborhood. Furthermore, it is possible to reconstruct an indoor environment by depth and color images on several position by using the multi-view camera. The reconstructed model can be adopted for interaction with as well as navigation in a virtual environment, and Mediated Reality (MR) applications.

• International Journal of Highway Engineering
• /
• v.2 no.1
• /
• pp.135-145
• /
• 2000

A new procedure needs to be developed to predict the dynamic layer properties under moving truck loads. In this study, a computer code to evaluate layer moduli of asphalt concrete pavement from measured interior deflections at various depths were developed and verified from numerical model tests. Interior deflections of the pavement are measured from Multi-Depth Deflectometer(MDD). It was found that errors between the given and backcalculated moduli in numerical analysis were less than 0.32% for several numerical models tested. When impact loads were used, a technique to determine the depth to virtual rigid base was proposed through the analysis of compressive wave velocity and impulse loading durations. It was found that errors between the given and backcalculated moduli in numerical analysis were less than 0.114% when virtual rigid base was considered in numerical analysis. The pavement behavior must be evaluated under various vehicle speeds when determining the dynamic interaction between the loading vehicle and pavement system. To evaluate the dynamic behavior on asphalt concrete pavement under various vehicle speeds, truck moving tests were carried out. From the test results with respect to vehicle speed, it was found that the vehicle speed had significant effect on actual response of the pavement system. The lower vehicle speed generates the higher interior deflections, and the lower dynamic modulus.

• Journal of Korean Society for Geospatial Information Science
• /
• v.19 no.2
• /
• pp.3-8
• /
• 2011

Recently, the demand for enterprise for service map providing and portal site services of a 3D virtual city model for public users has been expanding. Also, accuracy of the data, transfer rate and the update for the update for the lapse of time emerge are considered as more impertant factors, by providing 3D information with the web or mobile devices. With the latest technology, we have seen various 3D data through the web. With the VRML progressing actively, because it can provide a virtual display of the world and all aspects of interaction with web. It offers installation of simple plug-in without extra cost on the web. LiDAR system can obtain spatial data easily and accurately, as supprted by numerous researches and applications. However, in general, LiDAR data is obtained in the form of an irregular point cloud. So, in case of using data without converting, high processor is needed for presenting 2D forms from point data composed of 3D data and the data increase. This study expresses urban LiDAR data in 3D, 2D raster data that was applied by compressing algorithm that was used for solving the problems of large storage space and processing. For expressing 3D, algorithm that converts compressed LiDAR data into code Suited to VRML was made. Finally, urban area was expressed in 3D with expressing ground and feature separately.

• Herbal Formula Science
• /
• v.18 no.2
• /
• pp.227-239
• /
• 2010

Objective : The purpose of this study was to develop the simulator which can analyze the anti-inflammatory effects of herbs based on e-cell, or the virtual cell. Method : We have ensured the medical herbs and its active compounds by investigating the oriental medicine records and NBCI(Biomedicine database). Also we have developed the web-based search system for confirming database related to anti-inflammation. We have researched the cell signal pathway related with inflammatory response control and established the mathematical model of herb interaction on selected signal pathway in e-cell. Finally we have developed the prototype which can confirm the result of this model visibly. Results : We constructed the database of 62 cases of anti-inflammatory active compounds in 61 cases of medical herbs which have been known anti-inflammation effects in the paper, 16 cases of inflammatory factors, 10 cases of signal pathways related with inflammatory response and 6,834 cases of URL(Uniform Resource Locator) of referenced papers. And we embodied the web-based research system, which can research this database. User can search basic and detailed information of medical plants related with anti-inflammatory by using information system. And user can acquire information on an active compounds, a signal pathway and a link URL of related paper. Among investigated ten pathways, we selected NF-${\kappa}B$, which plays important role in activation of immune system, and we searched the mechanisms of actions of proteins which could be components of this pathway. We reduced total network into IKK-$I{\kappa}B$ - NF-${\kappa}B$, and completed mathematic modeling by using ordinary differential equations and response variables of $I{\kappa}B-NF-{\kappa}B$ signaling model network which is suggested by Baltimore Group. We designed OED(Ordinary Differential Equation) for response of IKK, $I{\kappa}B$, $NF-{\kappa}B$ in e-cell's cytoplasm and nucleus, and measured whether an active compound of medicinal plants which is inputted by an user would have a anti-inflammation effects in obedience to change in concentration over time. The proposed model was verified by using experimental results of the papers which are listed on NCBI.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.21 no.5
• /
• pp.15-27
• /
• 2022

An omnidirectional VR treadmill is a highly-immersive walking simulator that allows identical body movements, such as walking, running, and sitting. However, the operation difficulty of an omnidirectional VR treadmill may cause data reliability problems. Therefore, this study aims to verify the effectiveness of a VR treadmill by comparing the ability to orient in the real and virtual worlds spatially. For this purpose, a rotating and searching path experiment was conducted with participants. This experiment showed that there was no statistically significant difference in the ability of the participants to orient in the real and virtual worlds spatially. In addition, the omnidirectional VR treadmill requires an adaptation time for the users due to the difficulty in the treadmill operation. However, there was no significant difference in the difficulty felt by the participants according to the adaptation time. Hence, these findings supported the possibility of collecting realistic walking data without safety concerns through an omnidirectional VR treadmill. Furthermore, this treadmill could be used in future research to solve problems directly related to pedestrian safety, such as the interaction between vehicles and pedestrians.

• Archives of design research
• /
• v.20 no.3 s.71
• /
• pp.119-128
• /
• 2007

With the development of digital technologies, CAID became an essential part in the industrial design process. Creating photo-realistic images from a virtual scene with 3D models is one of the specialized task for CAID users. This task requires a complex interface of setting the positions and the parameters of camera and lights for optimal rendering results. However, the user interface of existing CAID tools are not simple for designers because the task is mostly accomplished in a parameter setting dialogue window. This research address this interface issues, in particular the issues related to lighting, by developing and evaluating TLS(Tangible Lighting Studio) that uses Augmented Reality and Tangible User Interface. The interface of positioning objects and setting parameters become tangible and distributed in the workspace to support more intuitive rendering task. TLS consists of markers, and physical controller, and a see-through HMD(Head Mounted Display). The user can directly control the lighting parameters in the AR workspace. In the evaluation experiment, TLS provide higher effectiveness, efficiency and user satisfaction compared to existing GUI(Graphic User Interface) method. It is expected that the application of TLS can be expanded to photography education and architecture simulation.

• Journal of the HCI Society of Korea
• /
• v.8 no.2
• /
• pp.21-27
• /
• 2013

Recently, the use of floating hologram has increased in many different aspects, such as exhibitions, education, advertisements, and so on. Especially, the floating hologram that makes use of half-mirror is widely used. Nevertheless, half-mirror, unfortunately, cannot lead users to the perfect three dimensional hologram experience. Even though it can make the vision look to be up on the air, it does not have the capacity to display itself up on the air, which is the ultimate goal of hologram. In addition, it looks inconsistent when a real object is located behind the half-mirror in order to show the convergence of the two (object and the half-mirror). In this paper, we did the study on comparison of 3D space perception for the stereoscopic AR holography. At first, we applied stereoscopic technology to the half-mirror hologram system for the accurate and realistic AR environment. Then, the users can feel as if the real 3D object behind half-mirror and the reflected virtual image are converged much better in the 3D space. Furthermore, by using depth camera, the location and direction of graphics can be controlled to change depending on the user's point of view. This is the effective way to produce augmented stereoscopic images simply and accurately through half-mirror film without any additional devices. What we saw from the user test were applying 3D images and user interaction leads the users to have 3D spatial awareness and realism more effectively and accurately.

• Journal of Korean Society of Steel Construction
• /
• v.25 no.4
• /
• pp.421-430
• /
• 2013

To predict behaviors of offshore wind turbines which are highly laterally loaded structures and to design them rationally, evaluating the soil-foundation interaction is important. Nowadays, there are many soil modeling methods for structural analysis of general structures subjected to vertical loads, but using the methods without any consideration for design of a monopile foundation is eschewed because it might cause wrong structural design due to the deferent loading state. In this paper, we identify the differences of the member forces and displacements by design methods. The results show that fixed end method is barely suitable for monopile design in terms of checking the serviceability because it underestimate the lateral displacement. Fixed end method and stiffness matrix method underestimate the member forces, whereas virtual fixed end method overestimates them. The results of p-y curve method and coefficient of subgrade reaction method are similar to the results of 3D soil modeling method, and 2D soil modeling method overestimates the displacement and member forces as compared with other methods.

• Journal of the Korea Computer Graphics Society
• /
• v.8 no.2
• /
• pp.15-22
• /
• 2002

Image segmentation methods partition an image into meaningful regions. For image composition and analysis, it is desirable for the partitioned regions to represent meaningful objects in terms of human perception and manipulation. Despite the recent progress in image understanding, however, most of the segmentation methods mainly employ low-level image features and it is still highly challenging to automatically segment an image based on high-level meaning suitable for human interpretation. The concept of HCI (Human Computer Interaction) can be applied to operator-assisted image segmentation in a manner that a human operator provides guidance to automatic image processing by interactively supplying critical information about object boundaries. Intelligent Scissors and Snakes have demonstrated the effectiveness of human-assisted segmentation [2] [1]. This paper presents a method for interactive image segmentation for more efficient and effective detection and tracking of object boundaries. The presented method is partly based on the concept of Intelligent Scissors, but employs the well-established Canny edge detector for stable edge detection. It also uses "sewing method" for including weak edges in object boundaries, and 5-direction search to promote more efficient and stable linking of neighboring edges than the previous methods.