• Title/Summary/Keyword: Ins Choi

Search Result 104, Processing Time 0.022 seconds

PowerFLOW Simulation of the Hyundai Simple Model for Sunroof Buffeting (HSM의 썬루프 버페팅을 위한 PowerFLOW 해석)

  • Choi, Eui-Sung;Cyr, Stephane
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.24 no.3
    • /
    • pp.189-197
    • /
    • 2014
  • A simplified model in the shape of a wedge box with an opening on the roof was used to generate buffeting conditions at HMC. These measurements performed in controlled conditions are intended to validate the ability of CFD tools to predict buffeting. The results obtained by PowerFLOW are presented in this paper for buffeting and for the boundary layer development on the roof of the model when the roof opening is closed. The flow mechanisms that explain the behavior of the experimental sound pressure level(SPL) curve are described, and an improved setup is used to reproduce the flow structures that lead to the measured SPL.

Spontaneous Release of Glycosylphosphatidylinositol (GPI)-anchored Renal Dipeptidase from Porcine Renal Proximal Tubules

  • Park, Sung-Wook;Kang, Bok-Yun;Yoon, Hyun-Joong;Park, Eun-Mi;Choi, Kyong;Lee, Hwang-Hee Blaise;Hooper, Nigel M.;Park, Haeng-Soon
    • Archives of Pharmacal Research
    • /
    • v.25 no.1
    • /
    • pp.80-85
    • /
    • 2002
  • The incubation of porcine renal proximal tubules (PTs) resulted in the release of the Glycosylphosphatidylinositol (GPI)-anchored renal dipeptidase (RDPase, EC 3. 4. 13. 19) from the membrane after a lag period of approximately 6 hours. This spontaneous release of RDPase from the membrane was inhibited by antibiotics. When the incubation supernatant was added back to fresh PTs, both the antibiotic inhibition of RDPase release and the lag period disappeared. The released RDPase reacted with an anti-cross reacting determinant antibody indicating the presence of the Ins (1, 2-cyc)P. These results suggest that bacteria in the PTs, when incubated, grow find Secrete a phosphatidylinmsitol-specific phospholipase C (PIPLC). This enzyme then hydrolyses the GPI-anchored RDPase and is transferable. RDPase was purified following its release from the membrane by this simple and inexpensive method which may also be applied to other GPI-anchored proteins.

UGV Localization using Multi-sensor Fusion based on Federated Filter in Outdoor Environments (야지환경에서 연합형 필터 기반의 다중센서 융합을 이용한 무인지상로봇 위치추정)

  • Choi, Ji-Hoon;Park, Yong Woon;Joo, Sang Hyeon;Shim, Seong Dae;Min, Ji Hong
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.15 no.5
    • /
    • pp.557-564
    • /
    • 2012
  • This paper presents UGV localization using multi-sensor fusion based on federated filter in outdoor environments. The conventional GPS/INS integrated system does not guarantee the robustness of localization because GPS is vulnerable to external disturbances. In many environments, however, vision system is very efficient because there are many features compared to the open space and these features can provide much information for UGV localization. Thus, this paper uses the scene matching and pose estimation based vision navigation, magnetic compass and odometer to cope with the GPS-denied environments. NR-mode federated filter is used for system safety. The experiment results with a predefined path demonstrate enhancement of the robustness and accuracy of localization in outdoor environments.

Increased DNA Polymerase Fidelity of the Lamivudine Resistant Variants of Human Hepatitis B Virus DNA Polymerase

  • Hong, Young-Bin;Choi, Yong-Wook;Jung, Gu-Hung
    • BMB Reports
    • /
    • v.37 no.2
    • /
    • pp.167-176
    • /
    • 2004
  • Although efficient antiviral lamivudine is used for HBV-infected patients, a prolonged treatment with nucleoside analogs often results in lamivudine-resistant variants. In this study, we evaluated the fidelity of the lamivudine-resistant variants. The FLAG-tagged wild-type (FPolE) and Met550 variants (FPolE/M550A, M550V, and M550I) of HBV DNA polymerases were expressed in insect cells then purified. Like many other reverse transcriptases, no $3'{\rightarrow}5'$ exonuclease activity was detected in the HBV DNA polymerase. Since there is no proofreading activity, then the use of the site-specific nucleotide misincorporation method is beneficial. From the $f_{ins}$ value analysis, it is evident that M550I and M550V exhibit higher fidelity values than the wild-type HBV DNA polymerase, while M550A exhibits similar fidelity values. It is therefore suggested that lamivudine resistance comes from the stringency to dNTP binding and the discrimination of dCTP and lamivudine in M550V and M550I.

Study on the Localization Improvement of the Dead Reckoning using the INS Calibrated by the Fusion Sensor Network Information (융합 센서 네트워크 정보로 보정된 관성항법센서를 이용한 추측항법의 위치추정 향상에 관한 연구)

  • Choi, Jae-Young;Kim, Sung-Gaun
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.18 no.8
    • /
    • pp.744-749
    • /
    • 2012
  • In this paper, we suggest that how to improve an accuracy of mobile robot's localization by using the sensor network information which fuses the machine vision camera, encoder and IMU sensor. The heading value of IMU sensor is measured using terrestrial magnetism sensor which is based on magnetic field. However, this sensor is constantly affected by its surrounding environment. So, we isolated template of ceiling using vision camera to increase the sensor's accuracy when we use IMU sensor; we measured the angles by pattern matching algorithm; and to calibrate IMU sensor, we compared the obtained values with IMU sensor values and the offset value. The values that were used to obtain information on the robot's position which were of Encoder, IMU sensor, angle sensor of vision camera are transferred to the Host PC by wireless network. Then, the Host PC estimates the location of robot using all these values. As a result, we were able to get more accurate information on estimated positions than when using IMU sensor calibration solely.

Study on the Causes of Malfunctions of PCBs Applied to the Power Saving Mode of Electrical Systems and its Solution (전기시스템의 절전모드에 적용되는 PCB의 오작동 원인 개선에 관한 연구)

  • Park, Hyung-Ki;Choi, Chung-Seog
    • Journal of the Korean Society of Safety
    • /
    • v.28 no.3
    • /
    • pp.51-55
    • /
    • 2013
  • The purpose of this study is to find the causes of malfunctions and defective operation of printed circuit boards(PCBs) built into home refrigerators to perform power saving functions. This study performed an electrostatic test of a PCB built-in using an Auto Triggering system; lightning and impulse tests using an LSS-15AX; and an impulse test using an INS-400AX. From the analysis of a secondarily developed product, it was found that electrostatic discharge(ESD) caused more malfunctions and defective operations than electric overstress(EOS) due to overvoltage. As a result of increasing the condenser capacity of the PCB circuit, withstanding voltage was increased to 7.4 kV. In addition, this study changed the power saving mode and connected a varistor to the #2 pin of an IC chip. As a result, the system consisting of all specimens of a finally developed product was operated stably with an applied voltage of less than 10 kV. This study found it necessary to perform quality control at the manufacturing stage in order to reduce the occurrence of electrostatic accidents to IC chips built into a PCB.

A Generation Method of Spatially Encoded Video Data for Geographic Information Systems

  • Joo, In-Hak;Hwang, Tae-Hyun;Choi, Kyoung-Ho;Jang, Byung-Tae
    • Proceedings of the KSRS Conference
    • /
    • 2003.11a
    • /
    • pp.801-803
    • /
    • 2003
  • In this paper, we present a method for generating and providing spatially encoded video data that can be effectively used by GIS applications. We collect the video data by a mobile mapping system called 4S-Van that is equipped by GPS, INS, CCD camera, and DVR system. The information about spatial object appearing in video, such as occupied region in each frame, attribute value, and geo-coordinate, are generated and encoded. We suggest methods that can generate such data for each frame in semi-automatic manner. We adopt standard MPEG-7 metadata format for representation of the spatially encoded video data to be generally used by GIS application. The spatial and attribute information encoded to each video frame can make visual browsing between map and video possible. The generated video data can be provided and applied to various GIS applications where location and visual data are both important.

  • PDF

Analysis of Flow and Thermal Mixing Responses on Hot Water Discharge by Quencher Devices into an Annular Water pool (원환풀내에서 Quencher Device에 의한 고온수 분출로 일어나는 혼합유동에 관한 연구)

  • Choi, Seong-Seok;Kim, Jong-Bo
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
    • /
    • v.14 no.1
    • /
    • pp.21-30
    • /
    • 1985
  • One of the problems with the Boiling Water Reactor involves the flow and thermal mixings in the suppression water pool high pressure steam discharge into the pool in case of emergency core relief. Varioos heat sensitive devices and pumps for the reactor core cooling are installed in the middle of the suppression pool. Especially the pumps utilize pool water in order to cool the reactor core in emergency cases. In this case, the water temperature for the reactor cool ins should be below a certain temperature specified by the reactor design. In the present investigation, in other to determine the optimum locations of these pumping devices, numerical solutions have been obtained for the model to determine the f low mixing characteristics. Experimental investigations have also been carried out for the flow mixing and for the thermal mixing in the pool during the discharge. Considering that the discharge steam through the Quenching Device becomes hot water immediately in the water pool, the steam- equivalent hot water has been utilized. Examining these characteristices, it becomes possible to deform me the best locations for RCIC, LPCI , HPCI pumps in the suppression water pool for the emermency reactor core cooling.

  • PDF

A Study on MBES Error Data Removing using Motion Sensor (Motion Sensor를 이용한 MBES 오측자료 제거 연구)

  • Kang, Moon-Kwon;Choi, Yun-Soo;Chang, Min-Chol;Yoon, Ha-Su
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.28 no.1
    • /
    • pp.39-46
    • /
    • 2010
  • Sounding data is the essential source for the safety of ships navigation system, and fundamental to the reasonable usage and maintenance of the ocean as well. As IT tech, positioning equipment such as GPS and INS, echo sounder are developed, recently, the precise submarine topography database bas been built by Multi-Beam Echo Sounder. However, MBES data includes some inevitable error caused by several factor, and some data have errors where the terrain is wobble. The error, which causes the $moir\acute{e}$ pattern error is the main factor hindering the accuracy of MBES data results, and therefore it is necessary to figure out the main cause of the error for the improvement of the accuracy by removing error data. On this research, the main cause of the error data is studied by analyzing motion sensor value of data including the $moir\acute{e}$ pattern error. Thus, as the result of examination, it turns out that the $moir\acute{e}$ pattern error is related to the standard deviation of Roll, and error data values are results of the non-correspondence between Swath data and Roll values caused by the drastic change of Roll values. Accordingly, the error data is removed by comparing between the gradient of Swath data and Roll values. Finally, as the result of removing error data, it is expected to be able to estimate the quality of MBES using the standard deviation of Motion sensor's Roll value, and calculate the additive error factor, which minimize non-corresponding data, and also this research must be contributed to improve the accuracy of sounding for small vessels with lots of motion in the bad circumstance for navigation.

Development of Real-Time Vision Aided Navigation Using EO/IR Image Information of Tactical Unmanned Aerial System in GPS Denied Environment (GPS 취약 환경에서 전술급 무인항공기의 주/야간 영상정보를 기반으로 한 실시간 비행체 위치 보정 시스템 개발)

  • Choi, SeungKie;Cho, ShinJe;Kang, SeungMo;Lee, KilTae;Lee, WonKeun;Jeong, GilSun
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.48 no.6
    • /
    • pp.401-410
    • /
    • 2020
  • In this study, a real-time Tactical UAS position compensation system based on image information developed to compensate for the weakness of location navigation information during GPS signal interference and jamming / spoofing attack is described. The Tactical UAS (KUS-FT) is capable of automatic flight by switching the mode from GPS/INS integrated navigation to DR/AHRS when GPS signal is lost. However, in the case of location navigation, errors accumulate over time due to dead reckoning (DR) using airspeed and azimuth which causes problems such as UAS positioning and data link antenna tracking. To minimize the accumulation of position error, based on the target data of specific region through image sensor, we developed a system that calculates the position using the UAS attitude, EO/IR (Electric Optic/Infra-Red) azimuth and elevation and numerical map data and corrects the calculated position in real-time. In addition, function and performance of the image information based real-time UAS position compensation system has been verified by ground test using GPS simulator and flight test in DR mode.