• 제목/요약/키워드: $T_d$

검색결과 13,183건 처리시간 0.049초

고압 전동기 고정자 권선의 운전중 절연감시 시스템 개발 (Development of On-tine Partial Discharge Monitoring System for High-Voltage Motor Stator Windings)

  • 황돈하;심우용;박도영;강동식;김용주;송상옥;김회동
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 추계학술대회 논문집 전기물성,응용부문
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    • pp.224-226
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    • 2001
  • In this paper, a novel high-voltage motor monitoring system (HVMMS) is proposed. This system monitors the insulation condition of the stator winding by on-line measurements of partial discharge (PD). Sensor, EMC (Epoxy-Mica Coupler) is used for PD measurement PD signals are continuously measured and digitized with a peak-hold A/D converter to build the database of the high-voltage motor's insulation condition. Also, this system can communicate with the central monitoring system via RS-485. This helps more efficient operation and maintenance of the generator.

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3.0T 자기공명영상기기에서 시행한 3D-FLAIR 영상에서의 정상 안면신경의 조영증강 양상 (Enhancement Pattern of the Normal Facial Nerve on Three - Dimensional (3D) - Fluid Attenuated Inversion Recovery (FLAIR) Sequence at 3.0 T MR Units)

  • 현동호;임현경;박지원;김종림;이하영;박순찬;안중호;백정환;최충곤;이정현
    • Investigative Magnetic Resonance Imaging
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    • 제16권1호
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    • pp.25-30
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    • 2012
  • 목적: 3-T 자기공명영상장치에서 시행한 3D-FLAIR 및 3D-T1-FFE-FS영상에서의 정상안면신경의 조영증강 양상의 비교가 그 목적이다. 대상과 방법: 측두골 자기공명영상을 촬영한 환자 중 안면신경이상의 과거력이 없는 20명의 환자를 대상으로 하였다. 두 명의 영상의학전문의가 정상안면신경의 조영증강을 평가하기 위해 조영증강 전후의 3D-T1-FFE-FS영상과 3D-FLAIR영상을 2주 간격으로 독립적으로 분석하였다. 안면신경은 5개의 분절로 나누었고 조영증강의 정도는 없거나 약하게 혹은 강하게 되는 경우로 나누어 분석하였다. 결과: 3D-FLAIR영상에서 한 명의 평가자가 두 예의 안면신경 슬부에 약한 조영증강이 있다고 보았다. 3D-T1-FFE-FS영상에서는 13예의 안면신경에서 최소 한 분절 이상 조영증강이 있다고 하였고, 최소 한 명의 평가자가 안면신경의 총 100개 분절 중 17개의 분절에서 조영증강이 있다고 분석하였으며, 유양분절의 빈도가 가장 높았다. 3D-T1-FFE-FS영상에서 정상안면신경의 조영증강에 대한 평가자간의 일치도는 ${\kappa}$값 0.589로 우수하였다. 결론: 3D-T1-FFE-FS영상과 달리 3D-FLAIR영상에서 정상안면신경은 거의 조영증강되지 않는다.

인터뷰 - T$\ddot{U}$V S$\ddot{U}$D Korea/라이너 블록 Reiner Block 대표이사

  • 한국원자력산업회의
    • 원자력산업
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    • 제29권7호
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    • pp.58-60
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    • 2009
  • 시험 검사 인증 기술 컨설팅 분야의 세계적인 서비스 기업인 T$\ddot{U}$V S$\ddot{U}$D 그룹의 한국 법인인 T$\ddot{U}$V S$\ddot{U}$D Korea가 최근 원자력 기기 및 시스템 설계 엔지니어링 기업인 (주)GNEC를 인수, 합병하면서 국내 원자력 시장에 성큼 진출하는 한편 우리나라 원자력사업의 해외 시장 진출을 적극적으로 도울 계획을 세우고 있다. 라이너 블록 사장은 GNEC 인수 후 기자회견을 통해 "원자력 기기 및 설계, 교육 및 엔지니어링 서비스 등 관련 기술 지원에 앞장서 국내 에너지 산업의 활성화에 앞장서는 것을 물론 국내 원자력 산업의 해외 진출을 지원하면서 중국, 인도 및 중국 등 아시아 시장에 적극 진출할 것" 이라고 말하고 "원전 관련 기술을 갖고 있는 다른 기업에 대해서도 향후 인수 합병(M&A)에 나설 계획"이라고 밝혔다. T$\ddot{U}$V S$\ddot{U}$D Korea가 GNEC 인수를 마무리한 시점인 지난 10월 19일, 한강이 내려다보이는 여의도 대한생명 63빌딩 12층 T$\ddot{U}$V S$\ddot{U}$D Korea 사장실에서 라이너 블록 사장을 만났다. 인터뷰 자리에는 이번 GNEC 합병에 큰 역할을 한 김두일 T$\ddot{U}$V S$\ddot{U}$D 고문이 배석하여 인터뷰를 도왔다.

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신갈나무와 굴참나무 천연림(天然林) 생태계(生態系)의 현존량(現存量) 및 물질(物質) 생산성(生産性)에 관한 연구 (Biomass and Net Primary Productivity in Natural Forests of Quercus mongolica and Quercus variabilis)

  • 송칠영;이수욱
    • 한국산림과학회지
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    • 제85권3호
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    • pp.443-452
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    • 1996
  • 충청북도 충주지역에서 평균수령 67, 62년생 신갈나무와 굴참나무 천연림을 대상으로 표준지를 선정하고 각 표준지에서 각각 10본의 표본목을 선정, 벌채하여 지상부의 현존량과 물질 생산성을 조사 분석하였다. 충주지역의 현존량 및 물질 생산성의 추정에 상대생장식을 사용하여 추정하였는데, 추정 방정식 모형으로는 $Wt=aD^bH^c$$Wt=a(D^2H)^b$, $Wt=aD^b$ 보다 적합하였고, 두 수종 모두 성분별 단목 현존량의 표본값과 추정치를 T-검정하여 본 결과 유의차는 없었다. 임분의 현존량은 신갈나무 임분의 지상부 총량이 130.6 t/ha였고, 굴참나무 임분이 137.4 t/ha였다. 부위별로는 신갈나무 임분의 경우, 엽 5.1 t/ha(3.9%), 죽은가지 3.5 t/ha(2.7%), 생지부 29.7 t/ha(23.0%), 수피 16.2 t/ha(l2.5%), 그리고 수간목부 74.9 t/ha(58.0%)였다. 굴참나무 임분은 엽 3.8 t/ha(2.9%), 죽은가지 2.9 t/ha(2.2%), 생지부 24.3 t/ha(l8.4), 수피 20.4 t/ha(15.5%), 그리고 수간목부 80.4 t/ha(61.0%)였다. 두 임분의 1년간 생산할 수 있는 지상부 총량은 각각 신갈나무 임분이 10.0 t/ha/yr, 굴참나무 임분이 8.6 t/ha/yr였다. 본 참나무 천연림은 장령림이지만 온대 활엽수림의 순생산량(5~10 t/ha/yr)과 거의 유사한 양을 보였다.

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ON PETERSON'S OPEN PROBLEM AND REPRESENTATIONS OF THE GENERAL LINEAR GROUPS

  • Phuc, Dang Vo
    • 대한수학회지
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    • 제58권3호
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    • pp.643-702
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    • 2021
  • Fix ℤ/2 is the prime field of two elements and write 𝒜2 for the mod 2 Steenrod algebra. Denote by GLd := GL(d, ℤ/2) the general linear group of rank d over ℤ/2 and by ${\mathfrak{P}}_d$ the polynomial algebra ℤ/2[x1, x2, …, xd] as a connected unstable 𝒜2-module on d generators of degree one. We study the Peterson "hit problem" of finding the minimal set of 𝒜2-generators for ${\mathfrak{P}}_d$. Equivalently, we need to determine a basis for the ℤ/2-vector space $$Q{\mathfrak{P}}_d:={\mathbb{Z}}/2{\otimes}_{\mathcal{A}_2}\;{\mathfrak{P}}_d{\sim_=}{\mathfrak{P}}_d/{\mathcal{A}}^+_2{\mathfrak{P}}_d$$ in each degree n ≥ 1. Note that this space is a representation of GLd over ℤ/2. The problem for d = 5 is not yet completely solved, and unknown in general. In this work, we give an explicit solution to the hit problem of five variables in the generic degree n = r(2t - 1) + 2ts with r = d = 5, s = 8 and t an arbitrary non-negative integer. An application of this study to the cases t = 0 and t = 1 shows that the Singer algebraic transfer of rank 5 is an isomorphism in the bidegrees (5, 5 + (13.20 - 5)) and (5, 5 + (13.21 - 5)). Moreover, the result when t ≥ 2 was also discussed. Here, the Singer transfer of rank d is a ℤ/2-algebra homomorphism from GLd-coinvariants of certain subspaces of $Q{\mathfrak{P}}_d$ to the cohomology groups of the Steenrod algebra, $Ext^{d,d+*}_{\mathcal{A}_2}$ (ℤ/2, ℤ/2). It is one of the useful tools for studying these mysterious Ext groups.

Effects of cultivation methods on methane emission in rice paddy

  • Kim, Sukjin;Choi, Jong-Seo;Kang, Shin-gu;Park, Jeong-wha;Yang, Woonho
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
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    • pp.319-319
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    • 2017
  • Methane is the main greenhouse gas released from rice paddy field. Methane from paddy fields accounts for 11 % of the global total methane emission. The global warming potential (GWP) of methane is 25 times more than that of carbon dioxide on a mass basis. It is well known that most effective practice to mitigate methane in paddy is related to the water management during rice growing season and the use of organic matters. This study was conducted to investigate the effects of tillage and cultivation method on methane emission in paddy. Tillage (tillage and no-tillage) and cultivation methods (transplanting and direct seeding) were combined tillage-transplanting (T-T), tillage-wet hill seeding (T-W), tillage-dry seeding (T-D) and no-till dry seeding (NT-D) to evaluate methane mitigation efficiency. Daily methane emission was decreased on seeding treatments (T-W, T-D, NT-D) than transplanting treatment (T-T). Amount of methane emission during rice growing season is highest in T-T ($411.7CH_4\;kg\;ha^{-1}y^{-1}$) and lowest in NT-D treatment (89.7). In T-W and T-D treatments, methane emissions were significantly decreased by 36 and 51 % respectively compared with T-T. Methane emissions were highly correlated with the dry weight of whole rice plant ($R^2=0.62{\sim}0.93$). T-T treatment showed highest $R^2$ (0.93) among the four treatments. Rice grain yields did not significantly differ with the tillage and cultivation methods used. These results suggest that direct seeding practice in rice production could mitigate the methane emissions without loss in grain yield.

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Cytoprotective Effect on Oxidative Stress and Inhibitory Effect on Cellular Aging of Terminalia chebula and Uncaria sinensis

  • Na, Min-Kyun;Hong, Nam-Doo;Kamiryo Yuko;Senoo, Yu-Ichiro;Yokoo Seiichi;Ito Shinobu;Miwa Nobuhiko
    • 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.201.3-201.3
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    • 2003
  • The ethanol extract from the fruit of Terminalia chebula (Combretaceae) and the hook of Uncaria sinensis (Rubiaceae) exhibited significant inhibitory activity on oxidative stress and the age-dependent shortening of the telomeric DNA length. In the peroxidation model using t-BuOOH, human epidermal keratinocytes-neonatal foreskin (HEK-N/F) cells were treated with the T. chebula and U. sinensis extracts. The results showed a notable enhancing effect on the cell viability of 60.5 ${\pm}$ 3.8 and 65.0 ${\pm}$ 3.0%, respectively, by 50 $\mu\textrm{g}$/ml of the extracts. (omitted)

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Differential Activation of T Cells by T-Cell Receptor Ligand Analogs

  • Choi, Yun-Hi;Suh, Yu-Jin;Kim, Kil-Hyoun
    • BMB Reports
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    • 제30권6호
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    • pp.415-420
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    • 1997
  • Although $CD4^+$ T cell responses to protein-derived antigen have well been understood, the epitopes recognized by hapten-specific $CD4^+$ T cells have not been fully defined. In this study, we characterized the response of a T cell hybridoma (5Di0.1B8) which is specific for a hapten. N-hydroxysuccinimidyl-4-azidobenzoate (HSAB) restricted by MHC class II $I-A^d$. Using three different antigen presenting cells (APCs) expressing $I-A^d$, the role of class II MHC proteins in haptenic antigen presentation and subsequent activation of 5D10.1B8 has been examined. Activation of 5D10.1B8 T cells by HSAB analogs was also performed. Our results show that each APC activated T cells differentially and that interleukin-2 (IL-2) augmented antigen-presenting ability of all the APCs, suggesting that increased expression of class II MHC protein by IL-2 played an important role in HSAB presentation and T cell activation. Finally, early T cell receptor-dependent signals induced by HSAB or its analogs were examined by phosphotyrosine immunoblot analysis, and showed that tyrosine phosphorylation level of a 18-20 kD protein increased upon stimulation.

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농업용 호소의 수질개선을 위한 오염총량관리제의 적용에 관한 연구 (A Study on the Application of Total Pollution Load Management System for Water Quality Improvement in Agriculture Reservoir)

  • 오대민;이영신
    • 한국환경보건학회지
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    • 제35권5호
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    • pp.365-375
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    • 2009
  • Agriculture reservoirs need a systematic approach that can control water purity and water improvement. The area under study, Bunam Lake exceeds the agricultural water standard level due to contamination from the upper stream. When the Taean Enterprise City was planned, the water quality improvement plan was applied to minimize the environmental change. However, in order to continuously maintain the water quality in the Bunam Lake, it was essential to apply the Total Pollution Load Management System (TPLMs). In order to achieve the targeted water quality in the Bunam Lake, standard flow rates and targeted water quality levels were applied to obtain the loading capacity which is as follows : BOD 1,891.2 kg/d, T-N 1,945.7 kg/d, T-P 131.7 kg/d. Also, the regional development load was calculated as, BOD 1,083.6 kg/d, T-N 942.2 kg/d, T-P 61.8 kg/d, which is required to be deceased :- by BOD 378.4 kg/d, T-N 198.9 kg/d, T-P 31.6 kg/d in order to safely achieve the targeted water quality in the Bunam Lake.

개에서 Tiletamine-Zolazepam 마취에 대한 Doxapram과 Yohimbine의 길항효과 (Antagonistic Effects of Doxapram and Yohimbine on Tiletamine-Zolazepam Anesthesia in Dogs)

  • 박명호;김명철
    • 한국임상수의학회지
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    • 제12권1호
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    • pp.799-818
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    • 1995
  • This study was performed to examine the general anesthetic efficacy of tiletamine-zolazepam, a mixture of phencyclidine-derived tiletamine and benzodiazepine-related zolazepam. The antagonistic activities of doxapram and yohimbine to the anesthetic effects of tiletamine-zolazepam were also studied. Thirty healthy mongrel dogs were divided into three groups (each of 10) twenty minutes after being anesthetized with tiletamine-zolazepam : T-Z-S group(tiletamine-zolazepam-saline), T-Z-D group (tiletamine -zolazepam-doxapram), T-Z-Y group (tiletamine-zolaz.pam-yohim bine). Various parameters wert evaluated in terms of the onset and recovery time of analgesia, respiration rates, hear rates, body temperature, electrocardiogram, blood chemistry, and lymphocyte blastogenesis. The results obtained through these experiment could be summarized as follows: 1. he anesthetic efficacy of tiletamine-zolazepam was considered desirable, with the onset time of anesthesia being as short as 0.23-0.24 minutes. 2. Both of the antagonistic effects of yohimbine and doxapram on the anesthesia induced by liletamine-zolazepan were evaluated statistically significant(p<0.05) as the recovery time was shortened from 39.3$\pm$4.9 min(T-Z-S group) to 25.3$\pm$2.9 nin(T-Z-Y group) and 29.9$\pm$8.8min(T-Z-D group), respectively. 3. Respiration rates were not changed by the treatments of both doxapram and yohimbine, with the only transient increase in the T-Z-D group. The changes in the respiration rate were not observed during the whole time course of the experiment. 4. Yohimbine(T-Z-Y group) increased the heart rate significantly from 30 minutes after the adminstration compared to the T-Z-S group and T-Z-D group (p<0.05). 5. The decreases in th, body temporature were observed from 30 minutes in the T-Z-S group(p<0.05) and 40 minutes in th, T-Z-D group(p<0.05), after the adminstration. On the other hand, there was no hypothermia in the T-Z-Y group. 6. In the all experimental groups of the T-Z-S, T-Z-D and T-Z-Y, there were no specific findings on the electrocardiograph incept slight shift to the tachycardia in all cases. 1. We could not find any differences in the blood chemistry between all experimental groups (T-Z-S, T-Z-D and T-Z-Y). 8. the inhibition of the lymphocyte blastogenesis shown in the T-Z-S with 3 hours decreasing and thereafter restoring to the normal values up to the point 5 hours were not occurred in the T-Z-D and T-Z-Y groups. With the above results, we could conclude that both doxapram and yohimbine can be clinically used as recovery agents towards anesthesia by tiletamine- zolazepam fi:on the efficacy point of view, but yohimbine is more recommendable in this case if considering the recovery time and lymphocyte blastogenesis.

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