http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
PSC 거더교의 성능개선을 위한 외부 프리스트레싱 보강공법의 정착부 콘크리트 응력해석
김용운 ( Kim¸ Yong-woon ),이명곤 ( Lee¸ Myung-gon ),김대중 ( Kim¸ Dae-joong ),염환석 ( Yum¸ Hwan-seok ),김우 ( Kim¸ Woo ) 한국구조물진단유지관리공학회 2002 한국구조물진단유지관리공학회 학술발표대회 논문집 Vol.6 No.2
The development of external prestressing has been one of the major trends in improvement of structural performance of deteriorated concrete structures during the last decade. This paper deals with the technical problem related to the use of external prestressing for PSC girder bridges in order to emphasize a critical question of the splitting tensile stress in the concrete zone of the anchorage newly attached to the prestressed girder. By employing a program for nonlinear finite element analysis, a specific type of anchorage concrete zone was analyzed with certain parameters. The results show that the localized splitting tensile stress induced by the anchor pin bearing pressure is effectively controlled by the bottom bearing plate pressure, and the horizontal distance between the pin and the bearing plate is appeared to be a key parameter in designing of an optimal anchorage device.
YongWoon Ji,SangJun Lee,Jae wook Jeon 제어로봇시스템학회 2013 제어로봇시스템학회 국제학술대회 논문집 Vol.2013 No.10
This paper proposes a disparity post-processing method for noise reduction using standard deviation, and presents the design and implementation of pipelined dedicated hardware architecture for the real-time processing performance. In the proposed method, the optimal standard deviation is calculated first using the parameters generated by iterative experiments. Through these parameters, we can determine whether the pixel of interest has the correct disparity value and can remove error pixels. We implemented the proposed dedicated hardware architecture on a Xilinx Virtex5 FPGA. The average operating frequency of this system operated up to 80MHz, which enabled real-time streaming video processing at 60fps.
A Study of the Energy Spread Effect for an Electron Diffraction Experiment
YongWoon Parc,고인수 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.54 No.6
A 2.5 MeV electron beam for femtosecond electron diffraction is generated from a RF photocathode gun with the Brookhaven National Laboratory (BNL) gun IV type at the Pohang Accelerator Laboratory. We use a Ti:Sapphire laser system to illuminate the Cu photocathode with a 100 fs laser pulse. The energy spread of the electron beam is measured to be lower than 0.2% with a 23˚ phase for oblique laser injection. Beam charge is estimated to be as low as 1 pC. The chromatic coherence length is estimated to be 0.106A. The diffraction patterns for polycrystalline aluminium are studied numerically with several electron beam energies with finite energy spread. The blurred pattern is quantified to investigate the effect of the energy spread on the diffraction pattern. A higher energy electron beam blurs the diffraction image more than a lower energy one.
A Study on Data Sharing Scheme using ECP-ABSC that Provides Data User Traceability in the Cloud
YongWoon Hwang,Taehoon Kim,Daehee Seo,Im-Yeong Lee 한국인터넷정보학회 2022 KSII Transactions on Internet and Information Syst Vol.16 No.12
Recently, various security threats such as data leakage and data forgery have been possible in the communication and storage of data shared in the cloud environment. This paper conducted a study on the CP-ABSC scheme to solve these security threats. In the existing CP-ABSC scheme, if the data is obtained by the unsigncryption of the data user incorrectly, the identity of the data owner who uploaded the ciphertext cannot be known. Also, when verifying the leaked secret key, the identity information of the data user who leaked the secret key cannot be known. In terms of efficiency, the number of attributes can affect the ciphertext. In addition, a large amount of computation is required for the user to unsigncrypt the ciphertext. In this paper, we propose ECP-ABSC that provides data user traceability, and use it in a cloud environment to provide an efficient and secure data sharing scheme. The proposed ECP-ABSC scheme can trace and verify the identity of the data owner who uploaded the ciphertext incorrectly and the data user who leaked the secret key for the first time. In addition, the ciphertext of a constant size is output and the efficiency of the user's unsigncryption computation were improved.
함용운(YongWoon Ham) 고려대학교 보건과학연구소 2004 보건과학논집 Vol.30 No.2
Acori Graminei Rhizoma(AR) occupies a particular place in oriental folk medicine as so called tonic remedy. In order to investigate whether ARinfluenced cerebral ischemia induced neuronal and cognitive impairments, we examined the effect of AR on ischemia-induced cell death in the hippocampus, and on the impaired learning and memory in the Morris water maze and passive avoidance in rats. Rats were induced to 10 minutes of forebrain ischemia by four vessel occlusion (4-VO) and reperfused again. AR, when administered to rat at a dose of 100 ㎎/㎏ i.p. water extracts to 0 minutes and 90 minutes after 4-VO, significantly neuroprotective effects by 48.4% in the hippocampus of treated rats. For behavior test, rats were administered saline AR(100 ㎎/㎏ p.o.) daily for two weeks, followed by their training to the tasks. The animals were trained to find a platform in a fixed position during 5 days and then received a 90-s probe trial in which the platform was removed from the pool on the 6thday. In the passive avoidance, animals were one time per day for 1 week. Rats with ischemic insults showed impaired avoidance test. Treatment with AR produced a marked improvenent in escape latency to find the platform in the Morris water maze. AR reduced the ischemia-induced learning disability in the passive avoidance. Consistent with behavioral data, treatments with AR reduced ischemia-induced cell death in the hippocampal CA1 area. These results showed that AR have a protective effect against ischemia-induced neuronal loss and learning and memory damage. 석창포(石菖蒲)는 전통의학에서 신체를 강화시키는 치료제로서 알려져 있다. 신경(神經)과 인지(認知) 상해로 유도한 石菖蒲의 大腦 虛血에서의 영향을 연구하기 위하여 해마(海馬)의 세포를 고사(枯死)시킨 뇌허혈(腦虛血) 모델에서와 수중 미로(迷路) 실험과 수동회피(受動 回避) 반응에서의 학습(學習)과 기억(記憶)에 대한 석창포의 작용을 연구하였다. 실험방법은 백서(白鼠)에 10분간 대뇌에 전뇌허혈(前腦虛血)을 일으키고 재관류(再灌流)하였다. 前腦虛血 후 0분과 90분에 石菖蒲를 100 mg/kg의 농도로 복강주사를 한 결과 해마에서 48.4%의 신경 세포 보호(神經細胞保護)효과를 나타내었다. 행동실험에서는 100㎎/㎏의 농도로 물에 녹인 石菖蒲를 2주일간 경구(經口)투여하고 운동 학습을 시켰다. 학습은 5일간 고정된 도피대를 찾는 것을 가르치고(學習), 6일째는 도피대를 제거한 채 90초 내에 도피대가 있던 자리를 찾아가는 것이다(記憶). 受動 回避 반응운동은 하루에 한번씩 1주일동안 실시하였다. 腦虛血 유발된 백서(白鼠)는 回避 반응에서 장애(障碍)를 보였다. 행동실험과 해마의 CA1 부분에서 세포고사(細胞枯死)를 유도한 腦虛血에서 石菖蒲를 투여한 결과 石菖蒲는 신경세포 손상과 記憶과 學習의 장애로 유도한 腦虛血에서 신경 세포 보호(神經細胞保護)효과를 나타내었다.