• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.10
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• pp.1900-1907
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• 2010

In this paper, a recurrent cerebellar modulation articulation control with praticle swarm optimization (PSO) method has been investigated for improvement of noise attenuation performance in active noise control system. For narrow band noise, FXLMS and RCMAC has a partial satisfactory noise attenuation. However, noise attenuation performance is poor for broad band noise and nonlinear path since it has linear filter structure. To improve this problem, a RCMAC with PSO is proposed and it is shown that satisfactory noise attenuation performance is obtained by some simulations in duct system using harmonic motor noise and KTX cabin noise as a noise source.

• Journal of Korean Neurosurgical Society
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• v.59 no.5
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• pp.533-536
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• 2016

Pilocytic astrocytomas (PAs) are World Heath Organization Grade I tumors and are most common in children. PA calcification is not a common finding and has been reported more frequently in the optic nerve, hypothalamic/thalamus and superficially located cerebral tumors. We present a cerebellar PA in a 3-year-old male patient with cystic components and massive calcification areas. The residual tumor grew rapidly after the first operation, and the patient was operated on again. A histopathological examination revealed polar spongioblastoma-like cells. Massive calcification is not a common feature in PAs and can lead to difficulties in radiological and pathological differential diagnoses.

• The Korean Journal of Zoology
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• v.34 no.3
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• pp.382-388
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• 1991

쥐의 교핵내에서 대뇌피질(또는 소뇌핵) 면면시 소뇌교핵계(또는 대뇌교핵계)의 연접구조의 변화에 대한 전자현미경적 관찰결과, 대뇌교핵계의 수입로 차단의 경우 소뇌교핵계의 신경섬유는 교핵세포의 원위 가지돌기쪽으로 발아하며, 소뇌핵 병변시 서뇌교핵계의 신경섬유는 근위가지돌기와 연접을 형성하거나 또는 여러개의 가지돌기 부속물들과 사구체형 연접복합체를 형성함이 밝혀졌다. 이상의 연구는 광학현미경적 관찰에서 언급된 대뇌피질(또는 소뇌핵) 병변에 따른 교핵내 신경종말의 밀도증가에 대한 보고를 뒷받침해주며, 소뇌핵 병변시 운동결핍증의 시간경과에 따른 회복에 대한 신경해부학적 근거를 제시한다.

• Archives of Pharmacal Research
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• v.18 no.5
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• pp.295-300
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• 1995

These studies were designed to examine the effects of ginsenosides on glutamate neurotansmission. In primary cultures of rat cerebellar granule cells, ginsenosides (Rb1, Rc did not Rg1, $500\mug/ml$) increased glutamate release which was measured by HPLC. but HPLC, but Re did not shwo an elevation of glutamate release. However, all of these ginsenosides down-regulated N-methyl-D-aspartate (NMDA)-induced glutamate release. Rc strongly increased glutamate release and elevated intracellular clcium concentrations $([Ca_{2+}]_i)$ which was measured by ratio fluorometry with FURA-2AM. These results indicate that ginsenosides have a homeostatic effect on glutamate neurotransmission, and there is a structure-function relationship among the ginsenosides tested.

• Journal of Power System Engineering
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• v.14 no.5
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• pp.56-62
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• 2010

In this paper, a recurrent cerebellar modulation articulation control (RCMAC) has been developed for improvement of noise attenuation performance in active noise control system. For the narrow band noise, a filter-x least mean square (FXLMS) method has bee frequently employed as an algorithm for active noise control (ANC) and has a partial satisfactory noise attenuation performance. However, noise attenuation performance of an ANC system with FXLMS method is poor for broad band noise and nonlinear path since it has linear filtering structure. Thus, an ANC system using RCMAC is proposed to improve this problem. Some simulations in duct system using harmonic motor noise and KTX cabin noise as a noise source were executed. It is shown that satisfactory noise attenuation performance can be obtained.

• The Korean Journal of Physiology
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• v.29 no.1
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• pp.103-111
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• 1995

Intracellular recordings were obtained from Purkinje cells in rat cerebellar slices maintained in vitro. Adding tetrodotoxin to the superfusion solution produced a typical pattern of repetitive burst firing consisting of a cluster of action potentials followed by a long hyperpolarization. TTX-induced oscillatory activity was not due to modulation of membrane potential although underlying mechanisms for maintenance of oscillatory activity were influenced by membrane voltage. The mechanism of TTX-induced oscillation was not related to the presence or amplitude of $I_h$ and could still induce the oscillatory activity after blockade of $I_h$ by cesium. The result from an experiment in which QX-314 was injected intracellularly strongly suggested that TTX-induced oscillatory firing activity was due to blockade of post-synaptic $Na^{+}$ currents intrinsic to PCs.

• The Korean Journal of Physiology
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• v.30 no.1
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• pp.117-124
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• 1996

This study evaluated the hypothesis that motoneuron collaterals modulate the excitability of ventral spinocerebellar tract neurons. In acute cats, 128 ventral cerebellar tract cells were studied extracellularly to determine the effects of ventral root stimuli. The majority of the cells responded to ventral root stimulation with either short or long latency increases in spike discharge. In many cells with sufficient spontaneous activity ventral root stimulation also evoked a long lasting reduction in activity. In preparations with the dorsal root ganglion removed VSCT neurons had similar response properties. In some cells contralateral ventral root stimulation also evoked excitatory responses. These findings indicate the VSCT can provide the cerebellum with information regarding activity in the final output neurons of the motor system, the alpha motoneurons.

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.1186-1188
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• 1996

Neural networks and fuzzy systems have attracted the attention of many researehers recently. In general, neural networks are used to obtain information about systems from input/output observation and learning procedure. On the other hand, fuzzy systems use fuzzy rules to identify or control systems. In this paper we present a generalized FCMAC(Fuzzified Cerebellar Model Articulation Controller) networks, by integrating fuzzy systems with the CMAC(Cerebellar Model Articulation Controller) networks. We propose a direct adaptive controller design based on FCMAC(fuzzified CMAC) networks. Simulation results reveal that the proposed adaptive controller is practically feasible in nonlinear plant control.

• Journal of Korean Neurosurgical Society
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• v.30 no.sup2
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• pp.348-351
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• 2001

Hemangioblastoma is a benign tumor of vascular origin that develops usually in the posterior cranial fossa. We report a case of supratentorial leptomeningeal hemangioblastoma occurring in a 45-year-old man who received total removal of recurrent cerebellar hemangioblastoma four years ago. He was admitted for the evaluation of severe headache and magnetic resonance image showed a well-enhanced, extra-axial mass in the right parietal region. A presumptive diagnosis was meningioma. It was completely removed with the attached dura. Histological examination including immunohistochemical study showed typical findings of hemangioblastoma. It is emphasized that close observation may be necessary for hemangioblastoma, even after total removal.

• Journal of Korean Neurosurgical Society
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• v.38 no.6
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• pp.478-480
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• 2005

The authors describe a case of intracranial epidermoid cyst with fourth ventricle involvement. A 43-year-old woman presented with progressive aggravating headache and cerebellar syndrome due to a large tumor in the fourth ventricle, that extended into the left side of foramen of Luschka. The histopathological workup following gross total removal of tumor had revealed the typical features of an epidermoid cyst. Four months after surgery, the cerebellar sings recovered to normal with a remarkable improvement of headache. Epidermoid cysts involving the fourth ventricle have been known to be one of the most rare diseases in the central nervous system. This rare case is discussed and a review of the relevant literature is presented.