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5kWh Flywheel 에너지저장장치 시스템의 동특성 향상 설계 (Design of 5kWh Flywheel Energy Storage System to Improve Dynamics)

  • 박철훈;최상규;함상용;이성휘;윤동원;한영희
    • 한국정밀공학회지
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    • 제25권10호
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    • pp.99-106
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    • 2008
  • 5kWh FESS(Flywheel Energy Storage System) using AMB(Active Magnetic Bearing) has been under development and 1st trial system has been finished and run the operating test. Unfortunately, the test result was not satisfactory because FESS could increase the rotational speed up to 9,000 rpm only although the target rotational speed is 18,000rpm. It's because 1st bending mode frequency of flywheel shaft was too low and imbalance response was too big. To achieve the target speed, 1st bending mode and imbalance response must be improved and the whole FESS needed to be designed again. This paper presents the newly designed FESS and what has been changed from the 1st trial FESS to improve 1st bending mode and imbalance response. The experimental results to see how much 1st bending mode frequency was improved are presented, too.

한국 남해 광양만 퇴적물에서 와편모조류 시스트의 수직적 군집 분포 (Vertical Distribution of Dinoflagellate Cysts in Sediments from Gwangyang Bay, Korea)

  • 김소영;문창호;조현진
    • 한국수산과학회지
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    • 제36권3호
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    • pp.290-297
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    • 2003
  • To describe vertical distribution of dinoflagellate cysts in bottom sediments from Gwangyang Bay, three short-core sediment samples were collected with a gravity core sampler on 24 August 2001: St. 1 core (27.5 cm) in the northeastern part of the bay, St. 14 core (30.5 cm) in the southwestern part, and St. 16 core (25.9 cm) near Yeosu Sound. Total cyst densities generally decreased from the top of the sediment samples through the bottom. The highest cyst densities were observed at 2-3 cm in St. 1 core, 4-5 cm in St. 14 core, and 0-1 cm in St. 16 core respectavely. Living cysts were observed till the bottom of the sediment samples. The increase of heterotrophic dinoflagellate cyst proportion may indicate that the eutrophication process was recently escalated in the study area.

샌드위치패널심재로 활용한 St/BA 개질 다공성 경량 콘크리트의 특성 (Properties of St/BA Modified Cellular Lightweight Concrete as Sandwich Panel Core)

  • 강내민;노정식;도정윤;문경주;소양섭
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2003년도 학술.기술논문발표회
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    • pp.31-34
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    • 2003
  • Sandwich panel is composed of the facing sheets which support the external load, the cellular core with the low thermal conductivity and the adhesive agent to bond them. The cellular core was produced by binding lightweight cellular aggregates with cement and two types of acrylic base St/BA emulsion were added with a view to improving the workability ion due to high absorption of light weight aggregate and to develope more strength, respectively. This investigation is to comprehend the effect of the addition of two types of St/BA on thermal conductivity, calorific value and exhaustion content of noxious gas in addition re compressive and flexural strength. Flexural strength of the specimen made with St/BA-2 ranged 20kgf/cm2 to 25kgf/cm2 and was about 50% to 100% as high as that of the non-fiber specimen. Thermal conductivity was recorded from 2.0 to 3.0 kcal/mh$^{\circ}C$ and calorific value of St/BA modified specimen was much lower than that of commercial sandwich panel core of EPS and urethane. Careful caution has to be taken because generation of noxious gas such as CO, NO and SO2 tend to increase with addition of polymer cement ratio.

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E-beam 전조사법에 의한 SAPP-g-(AN/St) 섬유상 이온교환체의 합성 및 우라늄 흡착특성 (Synthesis of SAPP-g-(AN/St) Fibrous Ion-Exchanger by E-beam Pre-irradiation and Their Adsorption Properties for Uranium Ion)

  • 황택성;박진원;김광영
    • 폴리머
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    • 제25권1호
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    • pp.49-55
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    • 2001
  • 비닐계 단량체인 아크릴로니트릴과 스티렌을 E-beam 전조사법에 의해 폴리프로필렌 섬유에 그라프트 반응시켜 PP-g-(AN/St) 공중합체를 제조한 후 아미드옥심기와 슬폰기를 도입하여 이관능성 이온교환섬유를 제조하였다. 그라프트율은 단량체 내에 아크릴로니트릴의 조성이 감소할수록 증가하였으며 최대 101.1%이었고 최대 아미드옥심화율은 7.2 mmol/g이었다. 또한 섬유상 이온교환체의 초기 열분해 온도는 120 ${\circ}C$ 이었고 함수율은 공중합체 내에 아미드옥심화율이 증가할수록 감소하였고 슬폰화율이 증가할수록 증가하는 경향을 나타냈다. APP-g-AN, SPP-g-St, ASPP-g-(AN/St) 이온교환체의 우라늄 흡착량은 각각 12.4, 34, 38mg/g이었으며 최적 흡착시간은 약 50시간이었다. 우라늄 흡착 실험결과, 본 실험에서 합성한 이온교환체 ASPP-g-(AN/St)는 $UO_2^{2+}$에 대하여 우수한 성능을 보였다.

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Effect of the Electroacupuncture at ST36 in TMT-induced Memory Deficit Rats

  • Shim, Hyun-Soo;Park, Hyun-Jung;Lee, Hye-Jung;Shim, In-Sop
    • 동의생리병리학회지
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    • 제25권4호
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    • pp.691-696
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    • 2011
  • In order to the neuroprotective effect of electroacupuncture (EA), the present study examined the effects of electroacupuncture inacupoint ST36 (Stomach 36) on trimethyltin chloride (TMT)-induced cognitive impairments rat using the Morris water maze (MWM) task and immunohistochemistry staining. The rats were randomly divided into the following groups: naive rat (Normal), TMT injection rat (Control), TMT injection + EA treated rat inacupoint ST36 (ST36) and TMT injection + EA treated rat in non-acupoint, base of tail (Non-AC). Electroacupuncture (2Hz, 2mA, and 10 minutes)was applied either to the acupuncture point ST36 or the nonacupuncture point in the tail for the last 14 days. In the water maze test, the animals were trained to find a platform in a fixed position during 4d and then received 60s probe trial on the $5^{th}$ day following removal of platform from the pool. Rats with TMT injection showed impaired learning and memory of the tasks and treatment with EA in acupoint ST36 (P<0.05) produced a significant improvement in escape latency to find the platform after $2^{nd}$ day and retention trial in the Morris water maze. Consistent with behavioral data, treatment with EA in acupoint ST36 also significantly increased expression of Choline acetyltransferase (ChAT) and Acetylcholinesterase (AChE) immunoreactive neurons in the hippocampus compared to the Control group. These results demonstrated that EA in acupoint ST36 has a protective effect against TMT-induced neuronal and cognitive impairments. The present study suggests that EA in acupoint ST36 might be useful in the treatment of TMT-induced learning and memory deficit.

족삼리(足三里) (ST36) 자침(刺鍼)이 안면부(顔面部) 한열변화(寒熱變化)에 미치는 영향(影響) (Characteristics of Acupuncture at ST36 on Facial Thermography of Health Subject)

  • 김영태;김재효;황재호;김경식;손인철
    • Korean Journal of Acupuncture
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    • 제19권2호
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    • pp.13-33
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    • 2002
  • This study was examined for effects of acupuncture of Zusanli (ST36) on the facial thermography in health subjects. The volunteers who participating in this study had taken rest for 20 - 30 mins in room temperature (23-$25^{\circ}C$) before the examination and informed them what to prohibit smoking, drinking and administration of drug for the previous day. The thermography of face was taken using Infra-Red Imaging System (IR 2000, MEDI-CORE Co., Korea) by time interval of 15 minutes at 15 min before, just before and 15 min after, 30 min after and 45 min after acupuncture stimulation. Acupuncture was applied to the left ST36 for 30 mins. The results showed that acupuncture of ST36 significantly decreased the temperature of all the areas of facial surface comparing to those of control group. Also, it was observed that the quantities of thermal changes following acupuncture of ST36 been increased significantly at the A1, A4, A6, A7 and A9 ROIs (region of interest) comparing that of control group. Observed the thermography classified by ROI, it was clear the fact that acupuncture of ST36 could modulate the specific areas concerning to the facial pathway of Stomach Meridian, because the thermal responses following acupuncture of ST36 were specific at the A1, A2, A5 and A9 ROIs, relatively. These results suggest that acupuncture of ST36 may modulate thermal distributions and changes of facial areas concerned with Stomach Meridian.

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위암에서 유전자 메틸화와 CpG Island Methylator Phenotype 및 Helicobacter pylori균 감염과의 연관성 (DNA Methylation of Multiple Genes in Gastric Cancer: Association with CpG Island Methylator Phenotype and Helicobocter pylori Infection)

  • 전경화;원용성;신은영;조현민;임명구;진형민;박우배
    • Journal of Gastric Cancer
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    • 제6권4호
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    • pp.227-236
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    • 2006
  • 목적: 유전자 메틸화는 유전자의 서열에 영향을 주지 않으면서 유전자의 발현을 억제하고 세포분열 후 그대로 보존되는 후성적 변화이다. 위암조직과 정상위조직에서 hMLH1, p16, p14, COX-2, MGMT, E-cadherin 유전자와 MINT (MINT1, 2, 12, 25, 31)의 메틸화 상태를 검사하여 위암의 발생 과정에서의 작용과 CIMP 및 Helicobacter pylori균 감염을 포함한 임상병리학적인자와의 연관성을 알아보고자 하였다. 대상 및 방법: 위암과 정상위 신선 동결 조직 각각 36예를 대상으로 MSP (methylation-specific PCR)방법을 이용하여 메틸화 상태를 분석하였고 CIMP의 분석은 MINT1, MINT2, MINT12, MINT25, MINT31의 5개 marker를 대상으로 시행하였다. Helicobacter pylori균 감염여부는 Warthin-Starry silver 염색을 통하여 분류하였다. 결과: 위암 관련 유전자인 p14, p16, MGMT, COX-2, E-cadherin, hMLH1의 메틸화는 각각 14예(38.9%), 13예(36.1%), 8예(22.2%), 10예(27.8%), 21예(58.3%), 6예(16.7%)였다. MINT1과 MINT25의 메틸화는 위암조직에서 정상위조직에서보다 통계학적으로 유의하게 높게 관찰되었다. CIMP 양성률은 위암조직에서 44.4%로 높게 나타났으며 CIMP-H 위암은 환자의 연령과 종양크기와 연관이 있었다. CIMP 양성 위암은 p16 유전자의 메틸화와 연관이 있었고 p16 유전자의 메틸화는 조직학적으로 저분화, 미만형, 궤양형성하는 위암에서 낮게 나타났다. MINT1의 메틸화는 Helicobacter pylori균과 연관성이 있었다. 결론: 위암에서 hMLH1, p16, p14, COX-2, MGMT, E-cadherin, MINT (MINT1, 2, 12, 25, 31)의 불활성화에 DNA 메틸화가 작용함을 알 수 있었고, Helicobacter pylori균에 의한 위암발생에 MINT1의 메틸화가 연관이 있음을 알 수 있었다.

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