• 한국식품과학회지
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• 제5권4호
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• pp.240-248
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• 1973

1. myo-inositol의 산화(酸化) 생성물(生成物)인 inosose를 환원(還元)하여 ax.- 및 eq.-alcohol에 도달(到達)시켰다. 2. 2-O-(p-hydroxybenzoyl)-myo-inositol [IX], 4-O-(p-hydroxybenzoyl)-myo-inositol [X], O-(p-hydroxybenzoyl)-scyllo-inositol [XX], 그리고 2-O-(p-hydroxybenzoyl)-epi-inositol [XXVI] 등(等) 신화합물(新化合物) 4종(種)을 합성(合成)하였고 이것을 얻기 위하여 합성(合成)한 [V], [VI], [VII], [VIII], [XVIII], [XIX], [XXIV], [XXV] 등(等) 8종(種) 화합물(化合物)도 아직까지의 문헌(文獻)에 기재(記載)가 없는 화합물(化合物)들이다. 3. 여기서 합성(合成)한 ester [IX] [X], [XX], [XXVI] 4종(種)은 모두 항균력(抗菌力)이 나타나며 epi-inositol ester [XXVI] 의 Aspergillus oryzae에 대(對)한 항균력(抗菌力)이 가장 강력(强力)하게 나타난다. 이와 같이 항균력(抗菌力)은 화합물(化合物)의 입체구조(立體構造)와 관련(關聯)되는 것 같다.

• Transactions on Electrical and Electronic Materials
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• 제17권4호
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• pp.196-200
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• 2016

We have developed new electrostatic discharge (ESD) protection devices with, bidirectional flip chip transient voltage suppression. The devices differ in their epitaxial (epi) layers, which were grown by reduced pressure chemical vapor deposition (RPCVD). Their ESD properties were characterized using current-voltage (I-V), capacitance-voltage (C-V) measurement, and ESD analysis, including IEC61000-4-2, surge, and transmission line pulse (TLP) methods. Two BD-FCTVS diodes consisting of either a thick (12 μm) or thin (6 μm), n-Si epi layer showed the same reverse voltage of 8 V, very small reverse current level, and symmetric I-V and C-V curves. The damage found near the corner of the metal pads indicates that the size and shape of the radius governs their failure modes. The BD-FCTVS device made with a thin n- epi layer showed better performance than that made with a thick one in terms of enhancement of the features of ESD robustness, reliability, and protection capability. Therefore, this works confirms that the optimization of device parameters in conjunction with the doping concentration and thickness of epi layers be used to achieve high performance ESD properties.

• Investigative Magnetic Resonance Imaging
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• 제25권3호
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• pp.141-155
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• 2021

Purpose: To develop a 3D magnetic resonance fingerprinting (MRF) method for application in high resolution knee cartilage PD, T₁, T₂ mapping. Materials and Methods: A novel 3D acquisition trajectory with golden-angle rotating radial in k_xy direction and interleaved echo planar imaging (EPI) acquisition in the k_z direction was implemented in the MRF framework. A centric order was applied to the interleaved EPI acquisition to reduce Nyquist ghosting artifact due to field inhomogeneity. For the reconstruction, singular value decomposition (SVD) compression method was used to accelerate reconstruction time and conjugate gradient sensitivity-encoding (CG-SENSE) was performed to overcome low SNR of the high resolution data. Phantom experiments were performed to verify the proposed method. In vivo experiments were performed on 6 healthy volunteers and 2 early osteoarthritis (OA) patients. Results: In the phantom experiments, the T₁ and T₂ values of the proposed method were in good agreement with the spin-echo references. The results from the in vivo scans showed high quality proton density (PD), T₁, T₂ map with EPI echo train length (N_ETL = 4), acceleration factor in through plane (R_z = 5), and number of radial spokes (N_spk = 4). In patients, high T₂ values (50-60 ms) were seen in all transverse, sagittal, and coronal views and the damaged cartilage regions were in agreement with the hyper-intensity regions shown on conventional turbo spin-echo (TSE) images. Conclusion: The proposed 3D MRF method can acquire high resolution (0.5 mm³) quantitative maps in practical scan time (~ 7 min and 10 sec) with full coverage of the knee (FOV: 160 × 160 × 120 mm³).

• 한국결정성장학회지
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• 제32권3호
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• pp.83-88
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• 2022

이종 기판과 GaN의 물성 차이로 인해 발생하는 결함을 제어하기 위한 다양한 방법 중 동종 물질을 완충층으로 사용하는 LT-GaN 방법을 사용하여 완충층과 성장 온도의 상관성을 자체 제작한 성장 장비를 통해 확인하고자 하였다. 성장 온도에 따라 표면에 형성된 LT-GaN 결정성에 변화가 있었으며, annealing 후 LT-GaN가 나타내는 결정성에 따라 epiGaN의 응력 완화 효과에 차이점이 있었다. 반면 LT-GaN의 높은 결정성은 다결정을 형성하는 원인으로 작용하여 그 위에 성장하는 epi-GaN의 결정질을 저해하는 결과를 유발하였다.

• 한국환경보건학회지
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• 제38권3호
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• pp.195-203
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• 2012

Objectives: This paper aims to investigate the influence on stress hormones of job stress resulting from firefighting duties, as well as the degree of such influence. Methods: KOSS-26 and stress hormones such as norepinephrine (NE), epinephrine (EPI), adrenocorticotrophic hormone (ACTH), and cortisol were analyzed for 191 male firefighters from the western area of Incheon, the Incheon Industrial Complex, and Bucheon, Korea. Job stress and stress hormones were compared between a office working group and field-working group. Results: There was no significant difference in EPI and ACTH between the two groups. Change of stress hormones prior to engaging in typical duties, following typical duties, and immediately after field activities was examined. All the EPI, ACTH, and cortisol showed statistically significant changes with time, but not NE in the blood. In the field-working group, the cortisol levels in the blood of the firefighting and rescue groups showed notable differences depending on the time at which the measurements were taken. Conclusion: The differences in stress hormone levels depending on the type of duties of the firefighters were identified. Thus, interventions proper to job requirements is required in order to ease stress.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.63-63
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• 2009

In this work, we demonstrate 800V 4H-SiC power DMOSFETs with several structural alterations to observe static DC characteristics, such as a threshold voltage ($V_{TH}$) and a figure of merit ($V_B^2/R_{SP,ON}$). To optimize the static DC characteristics, we consider four design parameters; (a) the doping concentration ($N_{CSL}$) of current spreading layer (CSL) beneath the p-base region, (b) the thickness of p-base ($t_{BASE}$), (c) the doping concentration ($N_J$) and width ($W_J$) of a JFET region, (d) the doping concentration ($N_{EPI}$) and thickness ($t_{EPI}$) of epi-layer. Design parameters are optimized using 2D numerical simulations and the 4H-SiC DMOSFET structure results in high figure of merit ($V_B^2/R_{SP,ON}$>~$340MW/cm^2$) for a power MOSFET in $V_B{\sim}1200V$ range.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
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• pp.286-286
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• 1994

Thrombin (0.25 U/ml : TB), 소-피부 collagen (200 $\mu\textrm{g}$/ml : CG), adenosine 5'-diphesphate (4,0 $\times$ $10^{-5}$M : ADP), 및 epinephrine (4,0 $\times$ 10 $^{-5}$M : EPI)의 가토-혈소판 응집과 단백인산화작용에 미치는 PDE-I (3-isobutyl-1-methylxanthine : IBMX, 및 KR 30075), amitriptyline (AP), chlorpromazine (CP), 및 sodium nitrogrosside (SNP)의 염향을 비교-검토하였다. 그 결과, KR은 2,2 $\times$ $10^{-7}$M 이하의 $IC_{50}$/에서 EPI > ADP > CG > TB 순으로 각각을 억제하였으며, SNP 보다도 강하였고; KR-30075보다 약하나 IBMX, AP, 및 CP도 각 응집재의 작용을 억제하였으며 특히 EPI에 대하여 $10^{-8}$M 이하의 $IC_{50}$/에서 유의한 억제력을 보였다. 각 응집제들은 41 kD 인산화는 유의하게 증가시키며 47 kD와 20 kD 단백인산화는 감소시켰는데; 모든 항응집성 약물이 41 kD 인산화-증가는 유의하게 억제하였다, 아울러, AP와 CP는 47 kD 단백인산화-감소에 영향을 미치지 않았으나 20 kD 단백인산화-감소는 억제하였다. PDE-I (IBMX와 KR)와 SNP는 47 kD와 20 kD 단백인산화-감소를 다소 약화시켰으며, 43 kD와 22 kD 단백인산화를 KR > IBMX > SNP순으로 유의하게 증가시켰고, KR의 22 kD 단백인산화작용은 현저하였다.

• 한국정보통신학회논문지
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• 제5권3호
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• pp.573-579
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• 2001

소자의 고집적을 위한 특성분석 기술은 빠른 변화를 보이고 있다. 이에 따라 고집적 소자의 특성을 시뮬레이션을 통하여 이해하고 이에 맞게 제작하는 기술은 매우 중요한 과제 중의 하나가 되었다. 소자가 마이크론급에서 나노급 이하로 작아지면서 그에 맞는 소자개발을 위해 여러 가지 구조가 제시되고 있는데 본 논문에서는 TCAD를 이용하여 여러 가지 구조 중에서 고농도로 도핑된 ground plane 위에 적층하여 만든 EPI MOSFET를 조사하였다. 이 구조의 특성과 임팩트이온화와 전계 그리고 I-V특성 곡선을 저 농도로 도핑된 드레인(LDD)MOSFET와 비교 분석하였다. 또한 TCAD의 유용성을 조사하여 시뮬레이터로서 적합함과 나노구조 소자에서의 스켈링이론의 적합함을 보았다.

• 한국전기전자재료학회논문지
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• 제22권8호
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• pp.637-640
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• 2009

In this work, we demonstrate 800 V 4H-SiC power DMOSFETs with several structural alterations to obtain a low threshold voltage ($V_{TH}$) and a high figure of merit ($V_B\;^2/R_{SP,ON}$), To optimize the device performance, we consider four design parameters; (a) the doping concentration ($N_{CSL}$) of current spreading layer (CSL) beneath the p-base region, (b) the thickness of p-base ($t_{BASE}$), (c) the doping concentration ($N_J$) and width ($W_J$) of a JFET region, (d) the doping concentration ($N_{EPI}$) and thickness ($t_{EPI}$) of epi-layer. These parameters are optimized using 2D numerical simulation and the 4H-SiC DMOSFET structure results in a threshold voltage ($V_{TH}$) below $^{\sim}$3.8 V, and high figure of merit ($V_B\;^2/R_{SP,ON}$>$^{\sim}$200 $MW/cm^2$) for a power MOSFET in $V_B\;^{\sim}$800 V range.

• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 2002년도 Proceedings
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• pp.305-308
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• 2002

More complex radiotherapy techniques using multi leaf collimation(MLC) such as intensity-modulated radiation therapy(IMRT) has been increasing the significance of verification of leaf position and motion. Due to the reliability and robustness, quality assurance(QA) of MLC is usually performed with portal films. However, the advantage of ease of use and capability of providing digital data of electronic portal imaging devices(EPIDs) have attracted many attentions as alternatives of films for routine quality assurance in spite of the concerns about their clinical feasibility, efficacy, and the cost to benefit ratio. In our work, the method of routine QA of MLC using electronic portal imaging(EPI) was developed. The verification of availability of EPI images for routine QA was performed by comparison with those of the portal films which were simultaneously obtained when radiation was delivered and known prescription input to MLC controller. Specially designed test patterns of dynamic MLC were applied to image acquisition. Quantitative off-line analysis using edge detection algorithm enhanced the verification procedure in addition to on-line qualitative visual assessment. In conclusion, the EPI is available enough for routine QA with the accuracy of portal films.