• 제목/요약/키워드: Neuro-Science

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Starting Current Application for Magnetic Stimulation

  • Choi, Sun-Seob;Bo, Gak-Hwang;Kim, Whi-Young
    • Journal of Magnetics
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    • 제16권1호
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    • pp.51-57
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    • 2011
  • A power supply for magnetic-stimulation devices was designed via a control algorithm that involved a start current application based on a resonant converter. In this study, a new power supply for magnetic-stimulation devices was designed by controlling the pulse repetition frequency and pulse width. The power density could be controlled using the start-current-compensation and ZCS (zero-current switching) resonant converter. The results revealed a high-repetition-frequency, high-power magnetic-stimulation device. It was found that the stimulation coil current pulse width and that pulse repetition frequency could be controlled within the range of 200-450 ${\mu}S$ and 200-900 pps, respectively. The magnetic-stimulation device in this study consisted of a stimulation coil device and a power supply system. The maximum power of the stimulation coil from one discharge was 130 W, which was increased to 260 W using an additional reciprocating discharge. The output voltage was kept stable in a sinusoidal waveform regardless of the load fluctuations by forming voltage and current control using a deadbeat controller without increasing the current rating at the starting time. This paper describes this magnetic-stimulation device to which the start current was applied.

Intracavitary Radiation Therapy for Recurrent Cystic Brain Tumors with Holmium-166-Chico : A Pilot Study

  • Ha, Eun Jin;Gwak, Ho-Shin;Rhee, Chang Hun;Youn, Sang Min;Choi, Chang-Woon;Cheon, Gi Jeong
    • Journal of Korean Neurosurgical Society
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    • 제54권3호
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    • pp.175-182
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    • 2013
  • Objective : Intracavitary injection of beta-emitting radiation source for control of cystic tumors has been tried with a benefit of localized internal radiation. The authors treated cystic brain tumor patients with Holmium-166-chitosan complex (Ho-166-chico), composed of a beta-emitting radionuclide Holmium-166 and biodegradable chit polymer, and evaluated the safety and effective measurement for response. Methods : Twenty-two patients with recurrent cystic brain tumor and/or located in a deep or eloquent area were enrolled in this pilot study. The cyst volume and wall thickness were determined on CT or MRI to assess radiological response. The activity of Ho-166-chico injected via Ommaya reservoir was prescribed to be 10-25 Gy to the cyst wall in a depth of 4 mm. Results : There was neither complications related to systemic absorption nor leakage of Ho-166-chico in all 22 patients. But, two cases of oculomotor paresis were observed in patients with recurrent craniopharyngioma. Radiological response was seen in 14 of 20 available follow-up images (70%). Seven patients of 'evident' radiological response experienced more than 25% decrease of both cyst volume and wall thickness. Another 7 patients with 'suggestive' response showed decrease of cyst volume without definitive change of the wall thickness or vice versa. All patients with benign tumors or low grade gliomas experienced symptomatic improvement. Conclusion : Ho-166-chico intracavitary radiation therapy for cystic tumor is a safe method of palliation without serious complications. The determination of both minimal effective dosage and time interval of repeated injection through phase 1 trial could improve the results in the future.

Online Automatic Gauge Controller Tuning Method by using Neuro-Fuzzy Model in a Hot Rolling Plant

  • Choi, Sung-Hoo;Lee, Young-Kow;Kim, Sang-Woo;Hong, Sung-Chul
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.1539-1544
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    • 2005
  • The gauge control of the fishing mill is very important because more and more accurately sized hot rolled coils are demanded by customers recently. Because the mill constant and the plasticity coefficient vary with the specifications of the mill, the classification of steel, the strip width, the strip thickness and the slab temperature, the variation of these parameters should be considered in the automatic gauge control system(AGC). Generally, the AGC gain is used to minimize the effect of the uncertain parameters. In a practical field, operators set the AGC gain as a constant value calculated by FSU (Finishing-mill Set-Up model) and it is not changed during the operating time. In this paper, the thickness data signals that occupy different frequency bands are respectively extracted by adaptive filters and then the main cause of the thickness variation is analyzed. Additionally, the AGC gain is adaptively tuned to reduce this variation using the online tuning model. Especially ANFIS(Adaptive-Neuro-based Fuzzy Interface System) which unifies both fuzzy logics and neural networks, is used for this gain adjustment system because fuzzy logics use the professionals' experiences about the uncertainty and the nonlinearity of the system. Simulation is performed by using POSCO's data and the results show that proposed on-line gain adjustment algorithm has a good performance.

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네트워크기반의 이상침입탐지를 위한 퍼지신경망에 대한 연구 (A study on network-based Neuro-Fuzzy network for Anomaly Intrusion Detection)

  • 김도윤;서재현
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2004년도 봄 학술발표논문집 Vol.31 No.1 (A)
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    • pp.829-831
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    • 2004
  • 컴퓨터 네트워크의 확대 및 인터넷 이용의 급속한 증가에 따라 컴퓨터 보안문제가 중요하게 되었다. 따라서 침입자들로부터 위험을 줄이기 위해 침입탐지 시스템에 관한 연구가 진행되고 있다. 본 논문에서는 네트워크 기반의 이상 침입탐지를 위하여 뉴로-퍼지 기법을 적용하고자 한다. 불확실성을 처리하는 퍼지 이론을 이상 침입 탐지영역에 도입하여 적용함으로써 오용 탐지의 한계성을 극복하여 알려지지 않은 침입 탐지를 하고자 한다.

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Synthesis and Nrf2 Activating Ability of Thiourea and Vinyl Sulfoxide Derivatives

  • Shim, Young Sun;Hwang, Hyun Sook;Nam, Ghilsoo;Choi, Kyung Il
    • Bulletin of the Korean Chemical Society
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    • 제34권8호
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    • pp.2317-2320
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    • 2013
  • Thiourea and vinyl sulfoxide derivatives were designed based on the structures of sulforaphane and gallic acid, prepared and tested for HO-1 inducing activity as a measure of Nrf2 activation, and inhibitory effect on NO production as a measure of anti-inflammatory activity. Both series of compounds showed moderate activity on HO-1 induction, and no inhibitory effect on NO production. Interestingly the thiourea compound 6d showed better HO-1 induction (71% SFN) than the corresponding isothiocyanate compound 6a (55% SFN). Overall, it seemed that more efficient electrophile is needed to get more effective Nrf2 activator.

해조류 바이오매스로부터 Lactic acid를 제조하는 방법에 관한 연구 (A Study on the Method of Manufacturing Lactic Acid from Seaweed Biomass)

  • 이학래;고의석;심원철;김종서;김재능
    • 한국포장학회지
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    • 제28권1호
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    • pp.1-8
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    • 2022
  • 최근 전 세계적으로 코로나바이러스감염증-19(COVID-19)의 확산됨에 따라 비대면 서비스가 성장하고 이와 동시에 플라스틱 폐기물 문제가 더욱 심화되고 있다. 동시에 탄소중립과 지속가능한 순환경제와 같은 친환경 정책이 전 세계적으로 추진되고 있고 친환경 제품에 대한 높은 수요로 인해 패키징 업계에서도 PLA, PBAT 등을 사용한 친환경 포장재 개발과 새로운 비즈니스 모델 창출을 시도하고 있다. 본 연구에서는 이러한 환경적 이슈에 우리나라 남해와 제주도 연안에서 매년 대량으로 발생하여 여러 형태의 문제를 야기하고 있는 구멍갈파래(Ulva australis)를 새로운 대체 에너지 원료로서 활용하고자 묽은 산 전처리, 효소 당화, 발효 공정을 거쳐 해조류 바이오매스 유래 Lactic acid를 생산하고자 하였다. 일반적으로 해조류는 종, 수확장소, 시기 등에 따라 탄수화물의 함량과 당의 구성이 다양하며, Cellulose, Alginate, Mannan, Xylan 등의 다당류로 구성되어 있고 리그닌 성분을 함유하고 있지 않아 곡물·목질계 자원보다 유용한 특징이 있다. 구멍갈파래를 구성하고 있는 복합 다당체는 한가지 공정만으로 높은 추출 수율을 기대하기 어려우나 본 연구에서 제시된 묽은 산 및 효소 당화의 융합 공정은 구멍갈파래가 함유하고 있는 대부분의 당 추출이 가능하기 때문에 상업화 규모의 생산 공정 구축 시 높은 Lactic acid 생산 수율을 기대할 수 있을 것으로 사료된다.

Screening and Characterization of Novel Akt/PKB inhibitors, SWU5 and SWU9

  • Ko, Jong-Hee;Yeon, Seung-Woo;Lee, Hong-Sub;Kim, Tae-Yong;Noh, Dong-Youn;Shin, Kyong-Soon;Hong, Soon-Kwang;Kang, Sang-Sun
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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    • pp.168.2-168.2
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    • 2003
  • Akt/Ptotein Kinase B (PKB) is a serine/threonine kinase and activated by PI3K pathway. Akt/PKB regulates a variety of cellular responses including proliferations, differentiations and insulin signaling pathway. Recent evidence also indicates that the abnormal activities or expression of Akt/PKB is closely associated with cancer, diabetes and neuro-degenerative diseases. These findings mean that Akt/PKB is likely to be a new therapeutic target for the treatment of disease. (omitted)

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무용콘텐츠에 내재된 소매틱스의 뇌과학적 메커니즘 (Neuroscientific Mechanism from Somatics in Dance Contents)

  • 김은정
    • 한국콘텐츠학회논문지
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    • 제16권6호
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    • pp.365-373
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    • 2016
  • 본 연구는 소매틱스(Somatics)를 발전시킨 무용 콘텐츠(Dance Contents)의 신경과학적 매커니즘(neuroscientific mechanism)을 문헌연구를 통해 밝히고자 하였다. 이에 따라 첫째, 소매틱스에서 사용하는 뇌과학적 매커니즘을 정리하고 둘째, 무용에서 활용되고 있는 소매틱스 훈련법을 통해 적용된 훈련법에 내포된 뇌과학적 메커니즘을 문헌연구를 통해 밝혀보았다. 본 연구에서는 소매틱스를 휄든크라이스(Feldenkrais)로 제한하여 신경가소성(neuroplasticity), 고유수용감각(proprioception), 감각통합(sensory integration)를 통해 작동원리를 설명할 수 있었다. 연구결과 가가(Gaga)와 타말파(Tamalpa)는 휄든크라이스의 주요기법인 움직임을 통한 자각(awareness thorough movement)을 수용하여 고유수용감각을 통해 받아들인 정보들을 통해 새로운 네트워크를 형성하고 감각통합을 하는 방식을 취하였다. 본 연구는 무용 훈련 안에서 일어난 뇌와 신체 간의 작용원리를 과학적으로 설명하고, 안무자, 무용가들이 자신의 무용연구 및 훈련에 이를 적용하고, 뇌과학적 관점에서 신체 움직임의 작동원리를 설명할 수 있는 밑거름을 제공하는데 그 의의가 있다.

Post-Chlorination Process Control based on Flow Prediction by Time Series Neural Network in Water Treatment Plant

  • Lee, HoHyun;Shin, GangWook;Hong, SungTaek;Choi, JongWoong;Chun, MyungGeun
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제16권3호
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    • pp.197-207
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    • 2016
  • It is very important to maintain a constant chlorine concentration in the post chlorination process, which is the final step in the water treatment process (hereafter WTP) before servicing water to citizens. Even though a flow meter between the filtration basin and clear well must be installed for the post chlorination process, it is not easy to install owing to poor installation conditions. In such a case, a raw water flow meter has been used as an alternative and has led to dosage errors due to detention time. Therefore, the inlet flow to the clear well is estimated by a time series neural network for the plant without a measurement value, a new residual chlorine meter is installed in the inlet of the clear well to decrease the control period, and the proposed modeling and controller to analyze the chlorine concentration change in the well is a neuro fuzzy algorithm and cascade method. The proposed algorithm led to post chlorination and chlorination improvements of 1.75 times and 1.96 times respectively when it was applied to an operating WTP. As a result, a hygienically safer drinking water is supplied with preemptive response for the time delay and inherent characteristics of the disinfection process.