• 제목/요약/키워드: Improved PD

검색결과 226건 처리시간 0.029초

Segmentation of MR Brain Image Using Scale Space Filtering and Fuzzy Clustering (스케일 스페이스 필터링과 퍼지 클러스터링을 이용한 뇌 자기공명영상의 분할)

  • 윤옥경;김동휘;박길흠
    • Journal of Korea Multimedia Society
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    • 제3권4호
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    • pp.339-346
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    • 2000
  • Medical image is analyzed to get an anatomical information for diagnostics. Segmentation must be preceded to recognize and determine the lesion more accurately. In this paper, we propose automatic segmentation algorithm for MR brain images using T1-weighted, T2-weighted and PD images complementarily. The proposed segmentation algorithm is first, extracts cerebrum images from 3 input images using cerebrum mask which is made from PD image. And next, find 3D clusters corresponded to cerebrum tissues using scale filtering and 3D clustering in 3D space which is consisted of T1, T2, and PD axis. Cerebrum images are segmented using FCM algorithm with its initial centroid as the 3D cluster's centroid. The proposed algorithm improved segmentation results using accurate cluster centroid as initial value of FCM algorithm and also can get better segmentation results using multi spectral analysis than single spectral analysis.

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Development of the Large-area Au/Pd Transfer-printing Process Applying Both the Anti-Adhesion and Adhesion Layers (접착방지막과 접착막을 동시에 적용한 대면적 Au/Pd 트랜스퍼 프린팅 공정 개발)

  • Cha, Nam-Goo
    • Korean Journal of Materials Research
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    • 제19권8호
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    • pp.437-442
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    • 2009
  • This paper describes an improved strategy for controlling the adhesion force using both the antiadhesion and adhesion layers for a successful large-area transfer process. An MPTMS (3-mercaptopropyltrimethoxysilane) monolayer as an adhesion layer for Au/Pd thin films was deposited on Si substrates by vapor self assembly monolayer (VSAM) method. Contact angle, surface energy, film thickness, friction force, and roughness were considered for finding the optimized conditions. The sputtered Au/Pd ($\sim$17 nm) layer on the PDMS stamp without the anti-adhesion layer showed poor transfer results due to the high adhesion between sputtered Au/Pd and PDMS. In order to reduce the adhesion between Au/Pd and PDMS, an anti-adhesion monolayer was coated on the PDMS stamp using FOTS (perfluorooctyltrichlorosilane) after $O_2$ plasma treatment. The transfer process with the anti-adhesion layer gave good transfer results over a large area (20 mm $\times$ 20 mm) without pattern loss or distortion. To investigate the applied pressure effect, the PDMS stamp was sandwiched after 90$^{\circ}$ rotation on the MPTMS-coated patterned Si substrate with 1-${\mu}m$ depth. The sputtered Au/Pd was transferred onto the contact area, making square metal patterns on the top of the patterned Si structures. Applying low pressure helped to remove voids and to make conformal contact; however, high pressure yielded irregular transfer results due to PDMS stamp deformation. One of key parameters to success of this transfer process is the controllability of the adhesion force between the stamp and the target substrate. This technique offers high reliability during the transfer process, which suggests a potential building method for future functional structures.

A Study on Pd-based Electrode prepared by using Electroless Plating Method (무전해도금법을 이용한 Pd 기반 전극·제조에 관한 연구)

  • Hwang, In Hyuck;Lee, Dong Yoon;Kim, Sung Su
    • Journal of the Korean Applied Science and Technology
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    • 제35권4호
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    • pp.1338-1347
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    • 2018
  • In this study, Ti-mesh based electrodes were fabricated for the application of anode to the electrolysis process for wastewater treatment using Pd electroless plating method. The removal performance of the prepared Pd / Ti-mesh electrode was evaluated as representative dye RO16, and the durability and performance were maximized by varying the electrode manufacturing conditions. As a result, it was confirmed that the coating condition had no significant effect on the performance, and that the heat treatment process greatly affected the performance and the durability was improved. In addition, we tried to maximize performance and durability by complexing Ir, Ru, and Ta. However, as the thickness of the layer increased due to the limitation of the coating method, the resistance increased and the performance decreased accordingly.

Matrix Metalloproteinase-8 Inhibitor Ameliorates Inflammatory Responses and Behavioral Deficits in LRRK2 G2019S Parkinson's Disease Model Mice

  • Kim, Taewoo;Jeon, Jeha;Park, Jin-Sun;Park, Yeongwon;Kim, Jooeui;Noh, Haneul;Kim, Hee-Sun;Seo, Hyemyung
    • Biomolecules & Therapeutics
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    • 제29권5호
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    • pp.483-491
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    • 2021
  • Parkinson's disease (PD) is a neurodegenerative disorder that involves the loss of dopaminergic neurons in the substantia nigra (SN). Matrix metalloproteinases-8 (MMP-8), neutrophil collagenase, is a functional player in the progressive pathology of various inflammatory disorders. In this study, we administered an MMP-8 inhibitor (MMP-8i) in Leucine-rich repeat kinase 2 (LRRK2) G2019S transgenic mice, to determine the effects of MMP-8i on PD pathology. We observed a significant increase of ionized calcium-binding adapter molecule 1 (Iba1)-positive activated microglia in the striatum of LRRK2 G2019S mice compared to normal control mice, indicating enhanced neuro-inflammatory responses. The increased number of Iba1-positive activated microglia in LRRK2 G2019S PD mice was down-regulated by systemic administration of MMP-8i. Interestingly, this LRRK2 G2019S PD mice showed significantly reduced size of cell body area of tyrosine hydroxylase (TH) positive neurons in SN region and MMP-8i significantly recovered cellular atrophy shown in PD model indicating distinct neuro-protective effects of MMP-8i. Furthermore, MMP-8i administration markedly improved behavioral abnormalities of motor balancing coordination in rota-rod test in LRRK2 G2019S mice. These data suggest that MMP-8i attenuates the pathological symptoms of PD through anti-inflammatory processes.

Exchange Bias Perpendicular Magnetic Anisotropy by Buffer Layer and Inserted Layer in [Pd/Co]5/FeMn Multilayer ([Pd/Co]5/FeMn 막에서의 바닥층과 삽입층에 의한 교환바이어스수직자기이방성)

  • Joo, Ho-Wan;An, Jin-Hee;Lee, Mi-Sun;Kim, Bo-Keun;Choi, Sang-Dea;Lee, Kee-Am
    • Journal of the Korean Magnetics Society
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    • 제14권5호
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    • pp.192-195
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    • 2004
  • Magnetic properties by exchange biased perpendicular magnetic anisotropy in [Pd(0.8 nm)/Co(0.8 nm)]$_{5}$/FeMn(15 nm) multilayers deposited by dc magnetron sputtering system are investigated. As inserted Pd layer of interface between [Pd/Co] multilayer and FeMn film, the Hex of perpendicular anisotropy was improved from 127 Oe to 145 Oe. But result of an experiment by thermal stability, the Hex of the case that an inserted layer was inserted in decreased from low 20$0^{\circ}C$ in about 5$0^{\circ}C$ more if not inserted. If Ta was a buffer layer, the experiment results along material of buffer layer, the H$_{ex}$ obtained the largest 127 Oe. And if Pd was a buffer layer, H$_{ex}$ obtained the largest 169 Oe. Also, the Hc in buffer layer of Ta and Pd obtained the largest 203 Oe and 453 Oe, respectively.

A Study of PD System Effectiveness based on R&D Network Analysis (R&D 네트워크 분석을 통한 PD 제도 효과 연구)

  • Park, Mi-Yeon;Lee, Sangheon;Shen, Hongme;Leem, Choon Seong;Kim, Wooju
    • The Journal of Society for e-Business Studies
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    • 제20권3호
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    • pp.29-46
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    • 2015
  • Examined how it varied the knowledge network of the country along with R&D changes in planning policy for the research and development of government. Therefore, in this study, chronological Analysis analyzed separately the network between each entity of participate in the industry fusion source technology development business of industry trade and Energy. Planning policy of industrial fusion source technology development business, to change the starting point before and after 2012, before 2012 from selected planning issues at the center "planning committee" and in 2012 'PD' changes to a system for planning issues around. First of all, an attempt to analyze the R&D network based on the "planning committee" current situation of 2009~2011, from 2012 to analyze the variation of the R&D network with the introduction of the 'PD' system after it was analyzed by dividing the time in the current state of up to 2013. The results of the analysis, since the PD system was introduced, such as self-relationship (the form of planning user to run directly challenges the person was planning to challenge participants)is greatly improved, I was able to grasp the effect became clear. The more the self-relation, and the budding scholars considering that there is inequality of the planning, the introduction of the PD scheme, it can be seen to have resulted in a positive effect. These studies, quantitatively analyzed to improve the results to the effects associated with changes in the planning policy of the government, I think that there is a meaning in terms of presenting the future direction of R&D policy.

Research on Improvement of CH4 Reduction Performance of NGOC for CNG Bus (CNG 버스용 NGOC의 CH4 저감 성능 향상을 위한 연구)

  • Seo, Choong-Kil
    • Journal of the Korea Academia-Industrial cooperation Society
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    • 제18권5호
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    • pp.708-715
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    • 2017
  • Recently, in order to meet the stricter emission regulations, the proportion of after-treatments for vehicles and vessels has been increasing gradually. The objective of this study is to investigate the improvement of $CH_4$ reduction ability of natural gas oxidation catalyst (NGOC), which reduces toxic gases emitted from CNG buses. Thirteen NGOCs were prepared, and the conversion performance of noxious gases according to the type of supports, the loading amount of noble metal, and surfactant and aging were determined. Support Zeolite supported on No. 3 $NGOC(1Pt-1Pd-3MgO-3CeO_2/(46TiO_2+23Al_2O_3+23Zeolite)$ is an anionic alkali metal/earth metal component that improved the oxidation reactivity between CO and NO and noble metal dispersion, and thus enhanced the $CH_4$ reduction ability. As the loading amount of Pd, a noble metal with a high selectivity to $CH_4$, was increased, the number of reaction sites was increased and the ability to reduce $CH_4$ was improved. No. 11 $NGOC(1Pt-1Pd-3MgO-3CeO_2/(Z20+Al80)$(pH=8.5), to which nitrate surfactant had been added, exhibited well dispersed catalyst particles with no agglomeration and improved the $CH_4$ reduction ability by 5-15%. The $NGOC(2Pt-2Pd-3Cr-3MgO/90Al_2O_3)$(48h aging), which was mildly thermal aged for 48h, increased the $CH_4$ reduction ability to about 10% or less as compared with No. 12 NGOC(Fresh).

Partial Discharge Pattern Recognition using Neural Network (뉴우럴 네트워크에 의한 부분방전 패턴 인식)

  • Lee, June-Ho;Hozumi, Naohiro;Okamoto, Tatsuki
    • Proceedings of the KIEE Conference
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    • 대한전기학회 1995년도 하계학술대회 논문집 C
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    • pp.1304-1306
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    • 1995
  • In this study, a neural network algorithm through a data standardization method was developed to discriminate the phase-shifted partial discharge(PD) patterns such as a $\phi$-q-n pattern. Considering the PD measurement in the field, it is not so easy to acquire absolute phase angles of PD pulses. As a consequence, one of the significant problems to be solved in applying the neural network algorithm to practical systems is to develop a method that can discriminate phase-shifted $\phi$-q-n patterns. Therefore, authors established a new method which could convert phase-shifted $\phi$-q-n patterns to a standardized $\phi$-q-n pattern which was not influenced by phase shifting. This new standardization method improved the recognition performance of a neural network for the phase-shifted $\phi$-q-n patterns considerably.

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Fabrication of Hydrogen Sensors Using Graphenes Decorated Nanoparticles and Their Characteristics (나노입자가 코팅된 그래핀 기반 수소센서의 제작과 그 특성)

  • Kim, Kang-San;Chung, Gwiy-Sang
    • Journal of Sensor Science and Technology
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    • 제21권6호
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    • pp.425-428
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    • 2012
  • This paper presents the fabrication and characterization of graphene based hydrogen sensors. Graphene was synthesized by annealing process of Ni/3C-SiC thin films. Graphene was transferred onto oxidized Si substrates for fabrication of chemiresistive type hydrogen sensors. Au electrode on the graphene shows ohmic contact and the resistance is changed with hydrogen concentration. Nanoparticle catalysts of Pd and Pt were decorated. Response factor and response (recovery) time of hydrogen sensors based on the graphene are improved with catalysts. The response factors of pure graphene, Pt and Pd doped graphenes are 0.28, 0.6 and 1.26, respectively, at 50 ppm hydrogen concentration.

ISFET Glucose Sensor with Palladium Hydrogen Selective Membrane

  • Chung, Mi-Kyung;Kim, Seong-Wan;Lee, Sang-Sik;Park, Chong-Ook
    • Journal of Sensor Science and Technology
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    • 제21권2호
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    • pp.90-95
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    • 2012
  • This paper describes the development of a glucose biosensor based on ion sensitive field effect transistor(ISFET) with a palladium(Pd) modified ion sensing membrane. By adopting Pd as a hydrogen sensitive layer and integrating a screen-printed reference electrode, the sensitivity and stability were considerably improved due to the high permeability and selectivity of the Pd hydrogen selective membrane. This paper suggests a new approach for realizing portable and highly sensitive glucose sensors for diagnosing and treating diabetes mellitus.