• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 1997년도 추계학술대회 논문집
• /
• pp.375-379
• /
• 1997

Thermal drift of the machine tool spindle due to temperature increase dominates the major source of the machine tool error. To compensate the thermal errors, software based error correction methods could be implemented. In th~s case, we need model to map the relationship between temperature and thermal distortion. Traditionally, two or three different methods have been trled: step increase of spindle speed, constant, random. The latter two methods are described in the document of ISOlDIS230-3. In this research, three different methods were verified through the experiments from the viewpoint of compensation of thermal distortion. Constant spindle speed turned out good enough for monitoring the behavior of the thermal drift and modeling the relationship between temperature and thermal distortion.

• Investigative Magnetic Resonance Imaging
• /
• 제11권1호
• /
• pp.20-26
• /
• 2007

목적 : 본 연구는 3 T MRI 장비에 적합한 동물영상용 솔레노이드 (solenoid) 코일을 개발하고 최적화한 후, 실제 동물모델에 대한 영상을 획득하는 것을 목표로 수행되었다. 대상 및 방법 : 솔레노이드 코일은 반경 4 cm, 길이 10 cm의 아크릴 구조물에 너비 2 cm, 두께 0.05 cm, 길이 10 cm의 구리테잎으로 3번 감긴 형태로 제작하였고, 구리테잎을 감을 때는 실린더 축과 수직이 되도록 감았으며 테잎간의 간격은 2 cm로 하였다. 축전지(capacitor)는 2-100 pF사이의 용량을 이용하였고, 코일은 수신 전용으로서 디자인되었다. 결과 : 개발된 솔레노이드 코일의 신호대 잡음비 (Signal to Noise Ratio; SNR)는 CuSO4수용액 팬텀(CuSO4; 0.7 g/L)에서 985, 쥐 (rat)를 이용한 동물실험에서 995이었고, Qfactor는 unload된 경우 203-206, load된 경우 84-89정도로 측정되었다. 솔레노이드 코일을 이용하여 획득한 영상은 상대적으로 해상도 (resolution)가 높았으며, 코일 시뮬레이션(simulation)을 통해서 얻은 RF field의 균질성 (homogeneity) 또한 매우 우수하였다. 결론 : 본 연구를 통하여 고자장 3T MRI 장비에서 쥐와 같은 작은 동물의 영상을 획득할 때 솔레노이드 코일을 사용하면 보다 향상된 영상의 대조도, 해상도, 선명도를 얻을 수 있는 가능성을 확인 할 수 있었다.

• 동의생리병리학회지
• /
• 제18권1호
• /
• pp.230-235
• /
• 2004

We previously reported that the phytoprotein extracted from Acanthopanax senticosus (PA) had anti-carcinogenic anti-metastatic activity via increase of inhibition of gap junctional intercellular communication. In the present study investigated the immunomodulatory mechanism of phytoprotein isolated from the stem bark of Acanthopanax sentic (PA). PA was found to significantly stimulate macrophages producing TNF-α and IL-1β in vitro. It also showed tumori activity indicating that PA had the ability to stimulate macrophage directly. Moreover, PA induced the CDB/sup +/ CTL cy responses to recognize antigen on the B16-BL6 melanoma cells. Treatment of PA with B16-BL6 melanoma cells increased the proliferation of splenocytes compared with untreated control. These results demonstrate that PA immunomodulatory activity suggesting a useful anti-tumor agent applicable to treatment and prevention of cancer.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2003년도 하계학술대회 논문집 D
• /
• pp.2786-2788
• /
• 2003

본 논문에서는 생체자기신호의 잡음제거 기법 중 PCA(Principal Component Analysis) 알고리즘을 사용하여 효과적으로 노이즈를 제거하기 위한 방법을 제안하였다. 61 채널 SQUID 시스템을 이용하여 심자도 신호를 측정하였고, 40 채널 SQUID 시스템을 이용하여 뇌자도 신호를 측정하였다. 그리고, 측정한 신호 성분들을 제안한 방법을 이용하여 주성분들을 분리하였고, 이들 중에서 노이즈 성분을 추정하여 측정한 신호에서 제거하였다. 이러한 방법을 이용한 결과, 심자도 신호에 존재하는 펄스 노이즈로 인하여 왜곡된 생체 자기 신호의 노이즈를 감소 시킬 수 있었으며, 뇌자도 신호에 존재하는 외부 노이즈 성분을 제거하여 임상 진단에 유용한 데이터를 얻을 수 있었다.

• Journal of Acupuncture Research
• /
• 제20권5호
• /
• pp.133-150
• /
• 2003

Objective: Recently. many studies have showed the evidences of the effect of the Electro-acupuncture treatment through scientific. Methods : One of these methods is functional MRI. We performed electro-acupuncture on Zusanli(St36) and observed the change of brain activation using fMRI. Zusanli(St36) is located on the lateral side of the lower leg. 3 cun(寸) inferior to the Patella of the lower border. Theoretically and clinically. this point has been considered very important for gynecological disorders. spleen and stomach disorders. and psychological disorders. To see the effects of electro-acupuncture stimulation on Zusanli(St36). the experiment was carried out on twelve healthy volunteers. using the gradient echo sequence with the 3.0T whole-body fMRI system(ISOL). After the needle insertion on right Zusanli(St36). 2 Hz of electric stimulation was given for 30 seconds. repeated five times. with 30 seconds' intervals. The Image analysis including motion correction. talairach transformation, and smoothing was done with SPM99. Results ad conclusion : The electro-acupuncture stimulation on Zusanli(St36) activates Brodmann Area 6, 13, 2, 19, 21, 22, 39, 40, 38, 3which indicates the pathways of the electro-acupuncture stimulation on Zusanli(St36) and the possibility of the relationship of the electro-acupuncture stimulation on Zusanli(St36) with autonomic nervous system, internal organic system.

• Journal of Acupuncture Research
• /
• 제20권5호
• /
• pp.208-226
• /
• 2003

Objective : Recently many studies have showed the evidence of the effect of the acupuncture treatment through scientific methods. One of these methods is functional MRI. We performed electro-acupuncture on St40 and observed the change of brain activation using fMRI. Methods : To see the effects of electro-acupuncture stimulation on Fenglong(St40), the experiment was carried out on six healthy volunteers, using the gradient echo sequence with 3.0T whole-body MRI system(ISOL). after the needle insertion on right Fenglong(St40), 2 Hz of electric stimulation was given for 30 seconds, repeated five times, with 30 seconds' intervals. Results & Conclussion : Electro-acupuncture stimulation on Fenglong(St40) activated Brodmann's Areas of 2, 3, 4, 6, 9, 10, 13, 18, 22, 30, 40, 42, 43 which may be the central pathways of electro-acupuncture stimulation on Fenglong(St40).

• Journal of Acupuncture Research
• /
• 제20권5호
• /
• pp.187-207
• /
• 2003

Objective: Recently, many studies have showed the evidences of the effect of the acupuncture treatment through scientific methods. One of these methods is functional MRI. We performed electro-acupuncture on Liv3 and observed the change of brain activation using fMRI. Methods: To see the effect of electro-acupuncture stimulation on Liv3. the experiment was carried out on 12 healthy volunteers. using the gradient echo sequence with the 3.0T whole-body MRI system(ISOL). After the needle insertion on right Liv3. 2 Hz of electric stimulation was given for 30 seconds. repeated five times. with 30 seconds' intervals. The Image analysis including motion correction, talairach transformation. and smoothing was done with SPM99. Results : 1. Group averaged brain activation induced by bilateral electro-acupuncture stimulation on Liv3 activates Brodman Area 6, 13, 18, 19, 22, 31, 39, 44, 2. Group averaged brain deactivation induced by bilateral Electro-acupuncture stimulation on Liv3 activates Brodman Area 4, 6, 9, 19, 36, 37, 39. 3. Group averaged brain activation induced by unilateral(right side) electro-acupuncture stimulation on Liv3 activates Brodman Area 2, 3, 6, 9, 10, 22, 40, 42, 43. 4. Group averaged brain deactivation induced by unilateral(right side) electro-acupuncture stimulation on Liv3 activates Brodman Area 6, 18, 19, 28, 30, 31, 35, 37. 5. Brain region activated by motor stimulation activates Brodman Area 4, 6, 13, 19, 42.

• 감성과학
• /
• 제14권2호
• /
• pp.235-244
• /
• 2011

본 연구에서는 fMRI 기법을 활용하여 제품과 공감각적 은유가 적용된 제품 디자인에 표현된 미각적 요소와의 적합성 수준이 제품에 대한 신경학적 반응과 제품평가에 미치는 영향에 대하여 알아보고자 하였다. 사전조사를 통해 미각적 요소와 제품 간의 적합성 정도에 따라 제품디자인을 두 그룹으로 나누었다. 총 40개의 제품디자인이 실험자극물로 사용되었다. 총 15명의 건강한 오른손잡이 대학생들이 실험에 참가하였다. 실험은 총 2세션으로 구성되어 있고, fMRI scanning session에서 참가자들은 제품디자인을 관찰하였고, post-scanning session에는 제품디자인에 대한 선호도와 구매의도를 측정하였다. 실험결과 적합성이 높은 제품디자인이 낮은 제품디자인보다 선호도, 구매의도 모두 높게 나타났다. 뇌 반응의 경우 긍정적 보상과 관련된 미상핵(Caudate nucleus)과 피각(putamen) 영역이 적합성이 높은 조건의 제품디자인에서 더 많이 활성화 되는 것으로 나타났다.

• Journal of Acupuncture Research
• /
• 제20권4호
• /
• pp.66-84
• /
• 2003

Objectve : Recent stuides suggested that there is a strong correlation between acupuncture stimulation and its cortical activation. Another study showed that either positive or negative BOLD effects could be observed depending on anatomical structure in acupuncture. Methods : 1) Subjects and paradigms: Two separate stimulation paradigms were performed in this study. To see the effects of electro-acupuncture stimulation on K7(Fuliu), the experiment was carried out on six healthy volunteers, using the gradient echo sequence with the 3.0T whole-body MRI system(ISOL). After the needle insertion on right K7(Fuliu), 2 Hz of electric stimulation was given for 30 seconds, repeated five times, with 30 seconds' intervals. During the intervals while there was no electro-stimulation, the subjects performed motor task as a reference. The image analysis including motion correction, talairach transformation, and smoothing was done using SPM99. Results: The electro-acupuncture stimulation on K7(Fuliu) activated Brodmann's Areas of 9, 19, 23, 24, 31, 32, 39 which may be the central pathways of the electro-acupuncture stimulation on K7(Fuliu) and those brain areas may be related with the function of the electro-acupuncture stimulation on K7(Fuliu).

• 한국전문물리치료학회지
• /
• 제9권3호
• /
• pp.67-76
• /
• 2002

We report the reorganization of motor network resulted from intensive unilateral coordination training and the effect of cross education on the untrained side in patient with traumatic brain injury using functional magnetic resonance imaging (fMRI). A 22 year-old male patient who had suffered from diffuse axonal injury for 58 months showed coordination deficit in the left hand at initial examination. Intensive motor training including complex finger movements and coordination activities using a metronome was introduced to the patient 4 hours per day for a week. FMRI was performed on a 3T ISOL Forte scanner. All functional images were analyzed using SPM-99 software. Hand function was improved after training not only in the trained left hand, but also in the untrained right hand. There was no activation in the right primary motor area (M1) during left hand movement before training whereas robust activation of left M1 was demonstrated by the right hand movement. Profuse activation of bilateral prefrontal lobes was seen during both hand movements before training. After training of left hand, right M1 became prominently activated during the left hand motion. The activation of bilateral prefrontal lobes disappeared after training not only for the left hand movement but also for the right, which clearly demonstrated the effect of cross education. This case report demonstrated the learning-dependent reorganization of the M1 and the effect of cross education.