14 research outputs found
Genetic algorithms for 2D routing and scheduling problems
학위논문(박사)--서울대학교 대학원 :전기·컴퓨터공학부,2006.Docto
뇌기능 영상에 관한 연구 : 뇌기능 영상에서 소음의 영향에 관한 해석과 침술에의 응용
학위논문(박사) - 한국과학기술원 : 전기및전자공학과, 1999.2, [ v, [100] p. ]The susceptibility or blood oxygenation level dependent (BOLD) effect can be exploited to provide activation maps of the human brain by MRI when performing various tasks, which is now known as functional MRI (fMRI). Study of basic aspects of the fMRI, we have studied following two fMRI application areas, namely, 1) acoustic effect and 2) acupuncture effect, respectively.
First, MR acoustic sound or noise due to gradient pulsings has been one of the problems in MRI, both in patient scanning as well as in many areas of psychiatric and neuroscience research, such as brain fMRI. Especially in brain fMRI, sound noise is one of the serious noise sources, which obscure the small signals obtainable from the subtle changes occurring in oxygenation status in the cortex and blood capillaries. Therefore, we have studied the effects of acoustic or sound noise arising in fMR imaging of the auditory, motor and visual cortices. The results show that the acoustical noise effects on motor and visual responses are opposite. That is, for the motor activity, it shows an increased total motor activation while for the visual stimulation, corresponding (visual) cortical activity has diminished substantially when the subject is exposed to a loud acoustic sound. Although the current observations are preliminary and require more experimental confirmation, it appears that the observed acoustic-noise effects on brain functions, such as in the motor and visual cortices, are new observations and could have significant consequences in data observation and interpretation in future fMRI studies.
Secondly, another application of fMRI is to study on acupuncture effect. A preliminary study of the correlation between acupuncture points (acupoints) for the treatment of eye disorders suggested by ancient Oriental literature and the corresponding brain localization for vision described by Western medicine was performed using functional MRI. The Vision-related Acupoint () is located in the later...한국과학기술원 : 전기및전자공학과
Design of Preform in the Forging Process of the Ball-Joint Socket
The preform design in metal forging plays a key role in improving product quality, such as ensuring defect-free property and proper metal flow. In industry, preforms are generally designed by the iterative trial-and-error approach, but this approach leads not only to significant tool cost but also to the down-time of the production equipment. It is thus necessary to reduce the time and the man-power through an effective method of perform design. In this paper, the equi-potential lines designed in the electric field are introduced to find the preform shape. The equi-potential lines obtained by the arrangement of the initial and final shapes are utilized for the design of the preform, and then applied for obtaining a fine preform in the foging process of the ball-joint socket
Mid-air Tactile Stimulation Using Laser-Induced Thermoelastic Effects: The First Study for Indirect Radiation
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