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Chinese Physics B 2013年第7期22卷 96-103页

作者： M. j. park S. M. Lee j. W. Son O. M. Kwon E. j. Cha School of Electrical Engineering Chungbuk National University School of Electronic Engineering Daegu University Division of IT-Convergence Daegu Gyeongbuk Institute of Science & Technology Department of Biomedical Engineering School of MedicineChungbuk National University

We study the leader-following consensus stability and stabilization of networked multi-teleoperator systems with interval time-varying communication delays. With the construction of a suitable Lyapunov–Krasovskii functional and the utilization of the reciprocally convex approach, novel delay-dependent consensus stability and stabilization conditions for the systems are established in terms of linear matrix inequalities, which can easily be solved by various effective optimization algorithms. One illustrative example is given to illustrate the effectiveness of the proposed methods.

关键词： multi-teleoperator systems interval time-varying delay leader–following consensus problem Lyapunov method

Influence of Carrier Gas on Analysis of MgO Powders by Laser Ablation Inductively Coupled Plasma Mass Spectrometry

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journal of Materials Science & Technology 2009年第3期25卷 333-335页

作者： j.S. Lee Y.S. Lee C.j. park H.S. Lee D.S. Lee Department of Chemistry Yonsei University Material Analysis Team Korea Testing Laboratory Korea Research Institute of Standards and Science School of Material Science and Engineering Pusan National Univirsity

Laser ablation inductively coupled plasma mass spectrometry （LA-ICP-MS） has been widely adopted for the direct multi-elemental analysis with high sensitivity. Especially analysis of fine ceramics by LA-ICP-MS without time-consuming sample decomposition process has been one of the most expecting application field. Small additive elements in MgO powders were analyzed by LA-ICP-MS. For precise and accurate analysis influence of carrier gas （Ar or He） was presented by the signal intensities of ICP-MS, relative standard deviation of signal intensities and ablated particle size distribution. Ablated particles were collected and analyzed by scanning electron microscopy （SEM） to investigate the particle size distribution, and the ablated sample surface was examined by camscope. In He gas atmosphere, the signal was more stable than in Ar gas atmosphere. The signal intensity was higher in Ar than in He. Examination of ablated particles and sample surface reveals that more particles were generated in Ar atmosphere and the distribution of particle size was larger.

关键词： Laser ablation MgO powders Carrier gas ICP-MS

Pathophysiological mechanisms underlying gastrointestinal symptoms in patients with COVID-19

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World journal of Gastroenterology 2021年第19期27卷 2341-2352页

作者： Byungchang jin Rajan Singh Se Eun Ha Hannah Zogg Paul j park Seungil Ro Department of Physiology and Cell Biology University of Nevada School of MedicineRenoNV 89557United States Department of Medicine Renown HealthRenoNV 89557United States

Gastrointestinal(GI)symptoms,such as diarrhea,abdominal pain,vomiting,and anorexia,are frequently observed in patients with coronavirus disease 2019(COVID-19).However,the pathophysiological mechanisms connecting these GI symptoms to severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infections remain *** studies indicate that the entry of SARS-CoV-2 into intestinal cells leads to downregulation of angiotensin converting enzyme 2(ACE2)receptors resulting in impaired barrier *** intestinal ACE2 functions as a chaperone for the amino acid transporter B0AT1,the B0AT1/ACE2 complex within the intestinal epithelium acts as a regulator of gut microbiota composition and *** to the B0AT1/ACE2 complex lead to microbial dysbiosis through increased local and systemic immune *** studies have also suggested that altered serotonin metabolism may be the underlying cause of GI disorders involving *** findings of elevated plasma serotonin levels and high fecal calprotectin in COVID-19 patients with diarrhea indicate that the viral infection evokes a systemic inflammatory response that specifically involves the ***,the elevated proinflammatory cytokines correlate with elevated serotonin and fecal calprotectin levels further supporting the evidence of GI inflammation,a hallmark of functional GI ***,the finding that rectal swabs of COVID-19 patients remain positive for SARS-CoV-2 even after the nasopharynx clears the virus,suggests that viral replication and shedding from the GI tract may be more robust than that of the respiratory tract,further indicating fecal-oral transmission as another important route of viral *** review summarized the evidence for pathophysiological mechanisms(impaired barrier function,gut inflammation,altered serotonin metabolism and gut microbiota dysbiosis)underlying the GI symptoms in patients with COVID-19.

关键词： COVID-19 Gastrointestinal symptoms Gut microbiota dysbiosis Impaired barrier function Serotonin Angiotensin converting enzyme 2 receptor

Power management unit chip design for automobile active-matrix organic light-emitting diode display module

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journal of Central South University 2009年第4期16卷 621-628页

作者： KIM j H park j H KIM j H CAO T V LEE T Y BAN H j YANG K KIM H G HA P B KIM Y H Department of Electronic Engineering Changwon National University 9 Sarim-Dong Changwon 641-773 Korea Denso PS Electronics Corporation 47 Seongsan-Dong Changwon 641-315 Korea

A power management unit （PMU） chip supplying dual panel supply voltage, which has a low electro-magnetic interference （EMI） characteristic and is favorable for miniaturization, is designed. A two-phase charge pump circuit using external pumping capacitor increases its pumping current and works out the charge-loss problem by using bulk-potential biasing circuit. A low-power start-up circuit is also proposed to reduce the power consumption of the band-gap reference voltage generator. And the ring oscillator used in the ELVSS power circuit is designed with logic devices by supplying the logic power supply to reduce the layout area. The PMU chip is designed with MagnaChip＇s 0.25 μ high-voltage process. The driving currents of ELVDD and ELVSS are more than 50 mA when a SPICE simulation is done.

关键词： DC-DC converter AMOLED charge pumping power management unit (PMU) dual panel supply voltage

Properties of Dispersion Casting of Y2O3 Particles in Hypo,Hyper and Eutectic Binary Al-Cu Alloys

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journal of Materials Science & Technology 2008年第1期24卷 57-59页

作者： j.j.park G.H.Kim S.M.Hong S.H.Lee M.K.Lee C.K.Rhee Nuclear Nano-Materials Development Lab. Korea Atomic Energy Research Institute （KAERI） 150 Deukjin-dongYuseong-gu Daejeon Korea

In the present work,the dispersion casting of Y-2O-3 particles in aluminum-copper alloy was investigated in terms of microstructural changes with respect to Cu contents of 20 （hypo）,33 （eutectic） and 40 （hyper） wt pct by scanning electron microscopy （SEM） and energy dispersive spectroscopy （EDS）.For the fabrication of Al-Cu alloy dispersed Y-2O-3 ceramic particles,stir casting method was *** case of Al-20 wt pct Cu alloy （hypoeutectic）,SEM images revealed that primary Al was grown up in the *** that,eutectic phase with well dispersed ceramic particles was *** case of eutectic composition,Y-2O-3 particles were uniformly dispersed in the *** the Cu is added into Al up to 40 wt pct （hypereutectic）,primary phase was grown up without any Y-2O-3 ceramic particles in the early stage of ***, eutectic phase was formed with well dispersed ceramic *** can be concluded that Y-2O-3 ceramic particles is mostly dispersed in case of eutectic composition in Al-Cu alloy.

关键词： Dispersion casting Y2O3 particles Stir casting Al-Cu alloy

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X射线定量相分析中的织构校正

物理学报 1995年第1期44卷 98-104页

作者：王超群 N.j.park H.j.Bunge Institfgr Melallkunde und Meiallphysik 北京100088 Institfgr Melallkunde und Meiallphysik 北京有色金属研究总院 Germany TU Claustal

采用Bunge法对Cu-Zn-AI形状记忆合金α相的定量分析进行织构校正.几种方法的比较结果表明Bunge法具有一系列优点.此外利用织构校正获得的c系数可用于三维取向分布函数(ODF)计算,回算极图与反极图,从而有可能在普通X射线衍射仪上由测量... 详细信息

采用Bunge法对Cu-Zn-AI形状记忆合金α相的定量分析进行织构校正.几种方法的比较结果表明Bunge法具有一系列优点.此外利用织构校正获得的c系数可用于三维取向分布函数(ODF)计算,回算极图与反极图,从而有可能在普通X射线衍射仪上由测量少数倾角的粉末强度数据估算ODF和进行低分辨织构分析如弹性和塑性计算等.

关键词：反极图三维取向分布函数织构定量相分析

A study on low emittance injector and undulator for PAL-XFEL

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High Power Laser Science and Engineering 2015年第3期3卷 41-49页

作者： j.Hong j.-H.Han S.j.park Y.G.jung D.E.Kim H.-S.Kang j.Pflueger Pohang Accelerator Laboratory European XFEL

For the success of PAL-XFEL, two critical systems, namely a low emittance injector and a variable gap out-vacuum undulator, are under development. In order to realize the target emittance of the PAL-XFEL injector we carried out an optimization study of various parameters, such as the laser beam transverse profile, the laser pulse length, the laser phase,and the gun energy. The transverse emittance measured at the Injector Test Facility(ITF) is εx=0.48±0.01 mm *** undulator prototype based on the EU-XFEL design and modified for PAL-XFEL was built and tested. A local-K pole tuning procedure was developed and tested. A significant reduction(90%) of the local-K fluctuation was observed. The requirement of undulator field reproducibility better than 2×10-4and the undulator gap setting accuracy below 1 μm were achieved for the prototype. The optical phase jitter after the pole height tuning at the tuning gap was calculated to be 2.6? rms, which satisfies the requirement of 5.0?.

关键词： emittance free-electron lasers(FELs) photocathode RF-gun undulator

Pre-Assembly Functionalization of Metal-Organic Frameworks

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Pre-Assembly Functionalization of Metal-Organic Frameworks

China’s Response to COVID-19:Turning Crisis into an Opportunity

中国化学会第六届全国结构化学学术会议

作者： j.park Department of Chemistry Texas A＆M UniversityCollege StationTX 77840USA

＜正＞Metal-organic polyhedrons（MOPs） and metal-organic frameworks（MOFs） have attracted a great deal of interests in the last two decades due to their crystalline nature,pore tunability,and structural *** addition,these exciting materials may lead to numerous potential applications such as gas storage/separation, catalysis,sensing and drug *** of the main challenges in MOF chemistry is how to construct a MOF

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China Today 2020年第5期69卷 14-16页

作者： TINA j.park the NATO Association of Canada

ON April 13,the number of the accumulated confirmed COVID-19 cases worldwide surpassed 1.8 million,with over 110,000 deaths,according to the COVID-19 Dashboard by the Center for Systems Science and Engineering(CSSE)at johns Hopkins *** around the world are struggling to contain the pandemic,taking measures ranging from total lockdown to travel bans,as well as financial injections to their respective *** public anxiety and paranoia continue to soar across the globe,experts predict a global recession in the near future.

关键词： travel fir COV

Effect of Polarization Dependent Loss on Polarization-Multiplexed Transmission System

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光学学报 2003年第S1期23卷 641-642页

作者： H. C. ji j. H. Lee K. j. park Y. C. Chung Department of Electrical Engineering KAIST 373-1 Guseong-dong Yuseong-gu Daejeon 305-701 KoreaDepartment of Electrical Engineering KAIST 373-1 Guseong-dong Yuseong-gu Daejeon 305-701 KoreaDepartment of Electrical Engineering KAIST 373-1 Guseong-dong Yuseong-gu Daejeon 305-701 KoreaNEC corporation Networking Research Laboratories Kawasaki JapanDepartment of Electrical Engineering KAIST 373-1 Guseong-dong Yuseong-gu Daejeon 305-701 Korea

We report on the effects of the polarization-dependent loss (PDL) on the polarization-multiplexed system. The result shows that the PDL of 0.9 dB could cause 1-dB power penalty. Unlike PMD, the effect of PDL was not d... 详细信息

关键词： PDL as of Effect of Polarization Dependent Loss on Polarization-Multiplexed Transmission System on