• Journal of Auto-vehicle Safety Association
• /
• v.14 no.4
• /
• pp.60-69
• /
• 2022

Recently, the importance of simulation validation in a virtual environment for autonomous driving system validation is increasing. At the same time, interest in the advancement of the virtual driving environment is also increasing. To develop autonomous driving technology, a simulation environment similar to the real-world environment is needed. For this reason, not only the road model is configured in the virtual driving environment, but also the driving environment configuration that includes the surrounding environments -traffic, object, etc- is necessary. In this article, FMTC, which is a test bed for autonomous vehicles, is implemented in a virtual environment and advanced to form a virtual driving environment similar to that of real FMTC. In addition, the similarity of the virtual driving environment is verified through comparative analysis with the real FMTC.

• Journal of Auto-vehicle Safety Association
• /
• v.15 no.1
• /
• pp.16-26
• /
• 2023

Recently, the importance of simulation in a virtual driving environment as well as real road-based tests for autonomous vehicle testing is increasing. Real road tests are being actively conducted at K-City, an autonomous driving test bed located at the Korea Automobile Safety Test & Research Institute of the Transportation Safety Authority. In addition, the need to advance the K-City virtual driving environment and build a virtual environment similar to the autonomous driving system test environment in real road tests is increasing. In this study, for K-City of Korea Automobile Safety Test & Research Institute, using detailed drawings and actual field data, K-City virtual driving environment was advanced, and similarity verification was verified through comparative analysis with actual K-City.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.9
• /
• pp.120-127
• /
• 2020

This study examined the operation of a pressure gauge for measuring the internal pressure of a barrel. During the ammunition performance evaluation test, the internal pressure of the barrel was measured mainly using a copper crusher gauge. The internal piezo gauge (IPG) was used to replace the pressure measurement method, and the test results were analyzed to verify the operability of the IPG. For verification, actual shooting test data were used, and a t-test was used to analyze the results. The 155MM KH179 and M119 series propellant were used for the test equipment and ammunition. The results confirmed that there was no difference between the mean values of the two data results at a significance level of 5% for the data values between the copper gauge and the IPG. The use of the IPG was verified by replacing the existing copper gauge to measure the internal pressure of the barrel, and it was confirmed that the application width could be widened in terms of diversity of test measurement methods. Based on the results of this test, it can be applied to the compression measurement test of various types of ammunition in addition to the propellant charges.

• Journal of Korean Neurosurgical Society
• /
• v.58 no.4
• /
• pp.368-372
• /
• 2015

Objective : The occurrence of acute cerebral infection following deep brain stimulation (DBS) is currently being reported with elevation of C-reactive protein (CRP) level. The aim of the present study was to establish normal range of the magnitude and time-course of CRP increases following routine DBS procedures in the absence of clinical and laboratory signs of infection. Methods : A retrospective evaluation of serial changes of plasma CRP levels in 46 patients undergoing bilateral, two-staged DBS was performed. Because DBS was performed as a two-staged procedure involving; implantation of lead and internal pulse generator (IPG), CRP was measured preoperatively and postoperatively every 2 days until normalization of CRP (post-lead implantation day 2 and 4, post-IPG implantation day 2, 4, and 6). Results : Compared with preoperative CRP levels ($0.12{\pm}0.17mg/dL$, n=46), mean CRP levels were significantly elevated after lead insertion day 2 and 4 ($1.68{\pm}1.83mg/dL$, n=46 and $0.76{\pm}0.38mg/dL$, n=16, respectively, p<0.001). The mean CRP levels at post-lead implantation day 2 were further elevated at post-IPG implantation day 2 ($3.41{\pm}2.56mg/dL$, n=46, respectively, p<0.01). This elevation in post-IPG day 2 rapidly declined in day 4 ($1.24{\pm}1.29mg/dL$, n=46, p<0.05) and normalized to preoperative value at day 6 ($0.42{\pm}0.33mg/dL$, n=46, p>0.05). Mean CRP levels after IPG implantation were significantly higher in patients whose IPGs were implanted at post-lead day 3 than those at post-lead day 5-6 ($3.99{\pm}2.80mg/dL$, n=30, and $2.31{\pm}1.56mg/dL$, n=16, respectively, p<0.05). However, there was no difference in post-IPG day 2 and 4 between them (p>0.05). Conclusion : The mean postoperative CRP levels were highest on post-IPG insertion day 2 and decreased rapidly, returning to the normal range on post-IPG implantation day 6. The duration of post-lead implantation period influenced the magnitude of CRP elevation at post-IPG insertion day 2. Information about the normal response of CRP following DBS could help to avoid unnecessary diagnostic and therapeutic efforts.

• The Transactions of the Korean Institute of Electrical Engineers D
• /
• v.50 no.10
• /
• pp.494-501
• /
• 2001

In this study, the effects of vascular parameter changes and electrodes on VOP measurement based on IPG were simulated mathematically. For the evaluation of the effects of hemodynamic changes on VOP, a mathematical model, which consists of cardiovascular system model and venous occlusion model, was developed and the model solution representing the blood flow and pressure in measuring point was found by 2nd order Runge-Kutta method. And, with sensitivity coefficients obtained from finite element solution of electric field in measuring point, the effects of electrode system on measurement were evaluated. As increasing the resistance, the venous capacitance was not changed but the venous outflows were decreased and the decreased compliance reduced the venous capacitance. And, for several configurations of round electrodes and band electrodes, the sensitivity coefficients were computed using the electric field distribution along deep vein. In conclusion, the proposed mathematical cardiovascular model could be applied to the simulation study on the effects of hemodynamic parameters on DVT diagnosis with IPG. And, also the sensitivity coefficients could provide effective electrode configuration for exact measurement of VOP.

• Proceedings of the KWS Conference
• /
• 2006.05a
• /
• pp.48-50
• /
• 2006

• Optical Science and Technology
• /
• v.14 no.2
• /
• pp.28-33
• /
• 2010

• Journal of Welding and Joining
• /
• v.31 no.4
• /
• pp.17-22
• /
• 2013

The excellent beam quality of high power fiber lasers are commonly used for remote welding applications in body job applications. The Welding speed and productivity is unmatched with any other welding technology including resistance spot welding or traditional laser welding. High tooling cost for clamping and bulky safety enclosures are obstacles which are limiting the use. With the newly developed Laser stitch welding gun we have an integrated clamping in the process tool and the laser welding is shielded in a way that no external enclosure is needed. Operation of this laser welding gun is comparable with resistance spot welding but 2-times faster. Laser stitch welding is faster than spot welding and slower than remote welding. It is a laser welding tool with all the laser benefits like welding of short flanges, weld ability of Ultra High Strength steel, 3 layers welding and Aluminium welding. Together with low energy consumption and minimum operation cost of IPG fiber laser it is a new and sharp tool for economic car body assembly.

• Proceedings of the Korean Society of Laser Processing Conference
• /
• 2005.11a
• /
• pp.15-17
• /
• 2005

• Journal of Broadcast Engineering
• /
• v.7 no.2
• /
• pp.153-167
• /
• 2002

With the advent of digital broadcasting, a large number of program channels become available at the user terminals such as set-top-box or PC. Channel navigation and searching become more difficult at TV terminal sides using a conventional device such as a TV remote controller. The MPEG-7 MDS (Multimedia Description Scheme) and TV Anytime set up a standard about how to describe user preferences for genre, channel, actor/actress, keyword, etc. of the TV programs, and how to describe usage history for user's program consumption behaviors and preferences. But they do not describe how to use them. In this paper, we describe an IPG (Intelligent Program Guider) system that provides TV program and channel information based on user preferences and suggest easy access to TV program that user wants. The IPG monitors user's behaviors of interacting to programs and automatically updates the user's preference changes according1y. The IPG utilizes user preferences description scheme specified in both MPEG-7 MDS and TV Anytime metadata specifications.