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White luminescence of Ho^(3+)/Tm^(3+)/Yb^(3+)-codoped CaWO_4 synthesized via citrate complex route assisted by microwave irradiation

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Transactions of Nonferrous Metals Society of China 2014年第S1期24卷 134-140页

作者： Hyun CHO Seok Min HWANG Jae Bin LEE Dong Hyun ka Tae Wan kim Bo Seul LEE Ji Young LEE Jung-Il LEE Jeong Ho RYU Department of Nanomechatronics Engineering Pusan National University50 Cheonghak-ri Miryang Gyeongnam 627-706 Korea Department of Materials Science and Engineering Korea National University of Transportation Chungju Chungbuk 380-702 Korea

The nanocrystalline Ho3+/Tm3+/Yb3+ co-doped CaWO4 upconversion(UC) phosphors were successfully synthesized by a modified citrate complex method using microwave irradiation. The citrate complex precursors were heat-treated at temperature ranging from 300 to 700 °C for 3 h. Crystallization of the Ho3+/Tm3+/Yb3+ co-doped CaWO4 was detected at 400 °C, and entirely completed at 600 °C. The Ho3+/Tm3+/Yb3+ co-doped CaWO4 heat-treated at 600 °C showed primarily spherical and homogeneous morphology. Under the laser excitation of 980 nm, Ho3+/Tm3+/Yb3+ co-doped CaWO4 shows the bright white upconversion(UC) emission visible to the naked eye, which is composed of a blue emission at 475 nm from Tm3+, and green and red emissions at 543 and 651 nm respectively from Ho3+. The coordinates of Ho3+/Tm3+/Yb3+ co-doped CaWO4 in the Commission International De'eclairage(CIE) chromaticity diagram could be controlled from a cool to a warm white color depending on the Tm3+ and Ho3+ concentrations. The UC luminescent properties on Tm3+ and Ho3+ concentrations and related mechanism based on laser pump power were discussed in detail.

关键词： upconversion CaWO4 microwave irradiation white luminescence

A Study of Address Shortage in a Tree Based ZigBee Network for Mobile Health Applications

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Wireless Sensor Network 2012年第5期4卷 147-153页

作者： ka Lun Lam Hoi Yan Tung King Tim Ko kim Fung Tsang Hoi Ching Tung Yat Wah Leung Wing Hong Lau Department of EE City University of Hong Kong Hong Kong China Department of SEEM City University of Hong Kong Hong Kong China

There are increasing demands for mobile health applications. This paper reports the development of a mobile health profile which dedicates to mobile applications. The mobile health profile is developed in association with the ZigBee Health Care profile and the IEEE 11073 standard which is normally applied to non-mobile applications. Since mobile sensors have to be carried by patients, the mobile health profile must facilitate mobility. In this investigation, a ZigBee fixed-mobile network (ZFMN) is defined and developed to supplement the ZigBee Health Care Profile for patient monitoring. The mobility study of ZigBee is performed using a random waypoint OPNET simulation model. In a ZFMN, the critical issue of address shortage is identified and discussed. It is analyzed that the problematic address shortage in a ZFMN may generate a huge amount of orphaned end devices and thus the packet drop percentage may potentially rise to 70%, rendering the network unable to function properly. Without introducing additional governing schemes, it is evaluated that the communication of the entire ZigBee network may paralyze. Further vigorous test are performed (by OPNET) on the communication capability of ZFMN when devices are randomly moving and sending data in 1s. It is vital to point out that under the adverse condition of address shortage, the performance of a ZFMN is still encouraging as long as the packet drop percentage has been kept below 3% before running out of address. The conclusion drawn in this analysis is that the packet drop percentage should be kept below 3% to provide a satisfactory QoS for an effective mobile health application using ZFMN such as patient monitoring. Such finding is also important for other future mobile application design of ZigBee. The address shortage issue is left as an open problem that needs attention for a resolution.

关键词： Mobile Health Patient Monitoring Mobility ZigBee Tree Address Assignment Address Shortage

A WiMAX-ZigBee Energy Management System for Green Education

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Smart Grid and Renewable Energy 2011年第4期2卷 338-348页

作者： Hoi Yan Tung kim Fung Tsang ka Lum Lam Hoi Ching Tung Rong Jian Zheng King Tim Ko Loi Lei Lai 不详

A WiMAX-ZigBee energy management system for green education has been developed. The system helps to resolve the disgusting environmental problems. This paper explores the concept of energy management and introduces an Energy Management System located at campus areas. Analysis shows that 30% energy can be saved from the total energy consumption which translates to a saving of 72 thousand million kWh of energy annually. Such saving reduces 48 million tons of CO2 emission for the environment.

关键词： Energy Management Minimizing CO2 Generation WiMAX ZigBee Green Education

Advanced Metering Infrastructure for Electric Vehicle Charging

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Smart Grid and Renewable Energy 2011年第4期2卷 312-323页

作者： Lun ka Lam King Tim Ko Hoi Yan Tung Hoi Ching Tung Wah Ching Lee kim Fung Tsang Loi Lei Lai 不详

The widely adoption of Electric Vehicle (EV) has been identified as a major challenge for future development of smart grids. The ever increasing electric vehicle charging further increases the energy demand. This paper reports the development of an Advanced Metering Infrastructure (AMI) as an effective tool to reshape the load profile of EV charging by adopting appropriate demand side management strategy. This paper presents a total solution for EV charging service platform (EVAMI) based on power line and internet communication. It must be stressed that the development of Third Party Customer Service Platform in this investigation facilitates a single bill to be issued to EV owners. Hence, EV owners understand their energy usage and thus may perform energy saving activity efficiently. Experiment and evaluation of the proposed system show that the throughput achieved is about 5 Mbps at 10 ms end to end delay in Power line Communication. By introducing two dimensional dynamic pricing and charging schedule, the proposed EVAMI successfully reduces 36% peak consumption and increases the “off peak” consumption by 54%. Therefore the EVAMI does not only reduce the peak consumption but also relocates the energy demand effectively.

关键词： Electric Vehicle Charging Advanced Metering Infrastructure Power Line Communication Demand Response

Vlodulation of ABA Signaling by Altering VxGФL Vlotif of PP2Cs in Oryza sativa

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Molecular Plant 2017年第9期10卷 1190-1205页

作者： Seungsu Han

The abscisic acid （ABA） signaling pathway is regulated by clade A type 2C protein phosphatases （PP2CAs） in plants. In the presence of ABA, PP2Cs release stress/ABA-activated protein kinases by binding to ABA-bound receptors （PYL/RCARs） for activation. Although the wedging tryptophan in PP2Cs is critical in the interaction with PYL/RCARs in Arabidopsis and rice, it remains elusive as to how other interface regions are involved in the interaction. Here, we report the identification of a conserved region on PP2Cs, termed the VxG4ФL motif, which modulates the interaction with PYL/RCARs through its second and fourth residues. The effects of the second and fourth residues on the interaction of OsPP2CS0 with several OsPYIJRCAR proteins were investigated by systematic mutagenesis. One OsPP2C50 mutant, VFGML （＂FM＂） mutant, lowered the affinity to OsPYL/RCAR3 by Ф15-fold in comparison with the wUd-type. Compar- ison of the crystal structures of wild-type OsPP2C50：ABA：OsPYI./RCAR3 with those composed of FM mutant revealed local conformational changes near the VxGФL motif, further supported by hydrogen-deute- rium exchange mass spectrometry. In rice protoplasts, ABA signaling was altered by mutations in the VxGФL motif. Transgenic Arabidopsis plants overexpressing OsPP2C50 and OsPP2C5OFM showed altered ABA sensitivity. Taken together, the VxGФL motif of PP2Cs appears to modulate the affinity of PP2Cs with PYL/RCARs and thus likely to alter the ABA signaling, leading to the differential sensitivity to ABA in planta.

关键词： ABA receptor type 2C protein phosphatase VxGФL motif Oryza sativa

Robust vision-based displacement measurement and acceleration estimation using RANSAC and kalman filter

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Earthquake Engineering and Engineering Vibration 2023年第2期22卷 347-358页

作者： Jongbin Won Jong-Woong Park Min-Hyuk Song Youn-Sik kim Dosoo Moon Department of Civil and Environmental Engineering Chung-Ang UniversityDongjakSeoul 06974Korea Department of Smart Cities Chung-Ang UniversityDongjakSeoul 06974Korea R&D Division Tantan Safety co.LtdSeongdongSeoul 04798Korea Department of Civil and Environmental Engineering University of Hawaii at ManoaHonolulu 96822USA

Computer vision(CV)-based techniques have been widely used in the field of structural health monitoring(SHM)owing to ease of installation and cost-effectiveness for displacement *** paper introduces computer vision based method for robust displacement measurement under occlusion by incorporating random sample consensus(RANSAC).The proposed method uses the kanade-Lucas-Tomasi(KLT)tracker to extract feature points for tracking,and these feature points are filtered through RANSAC to remove points that are noisy or *** the filtered feature points,the proposed method incorporates kalman filter to estimate acceleration from velocity and displacement extracted by the *** validation,numerical simulation and experimental validation are *** the simulation,performance of the proposed RANSAC filtering was validated to extract correct displacement out of group of displacements that includes dummy displacement with noise or *** the experiment,both RANSAC filtering and acceleration measurement were validated by partially occluding the target for tracking attached on the *** results demonstrated that the proposed method successfully measures displacement and estimates acceleration as compared to a reference displacement sensor and accelerometer,even under occluded conditions.

关键词： computer vision structural displacement structural acceleration RANSAC kalman filter

Synthesis and Characterization of Nanocapsules of α-Fe(NiCoAl) Solid-solution

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Journal of Materials Science & Technology 2005年第3期21卷 297-300页

作者： DianyuGENG J.C.kim C.J.Cho ChonglinCHEN XianguoZHAO ZidongZHANG ShenyangNationalLaboratoryforMaterialsScience InstituteofMetalResearchandInternationalCentretbrMaterialsPhysicsChineseAcademyofSciencesShenyang110016China KoreaInstituteofMachineryandMaterials 66Sangnam-dongChangwonKynugnam640-010SouthKorea

α-Fe(NiCoAl) solid-solution nanocapsules were prepared with pure powders of Fe, Ni, Co and Al by the plasma arc-discharging using a copper crucible. The shapes of the nanocapsules are in polyhedrons with the core/shell structure. The body centered cubic (BCC) phase is formed in the core. The size of the nanocapsules is in the range of 10-120 nm and the thickness of the shell is 4-11 nm. Saturation magnetization JS=150 Am2/kg and coercivity iHC=24.3 ka/m are achieved for the nanocapsules.

关键词： Nanocapsules a-Fe solid solution Plasma arc discharge Magnetic properties

Engineering of Materials for Respiratory Protection:Salt-Coated Antimicrobial Fabrics for Their Application in Respiratory Devices

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Accounts of Materials Research 2022年第3期3卷 297-308页

作者： Sumin Han Euna Oh Erin Keltie Jong Sung kim Hyo-Jick Choi Department of Chemical and Materials Engineering University of AlbertaEdmontonAB T6G 1H9Canada Health and Environments Research Centre(HERC) Department of Community Health and EpidemiologyFaculty of MedicineDalhousie UniversityHalifaxNS B3H 4R2Canada

CONSPECTUS:The development of a highly effective,low-cost method for protection against direct transmission through infectious media associated with respiratory diseases has been considered to be a major challenge in the management of the pandemic ***,filtration in respirators and masks depends on the mesh size,raising safety concerns about direct contact with the virus-laden layers of masks and respirators during use and ***,conventional medical face masks and respirators are recommended for single use only because long-term use and reuse of masks increase the risk of contact transmission of *** a result,mask reusability has gained much attention in addressing the global problem of respirator and mask shortages during the COVID-19 ***,coinfection by influenza,SARSCoV-2,and bacteria has been an ongoing issue in the current COVID-19 *** our response to the increasing demand for more convenient forms of disease control,our group has investigated antimicrobial technologies for respiratory devices against pandemic/epidemic diseases and developed two universal antimicrobial coating technologies:(1)nonwashable,reusable salt-coated fabrics and(2)washable,photopolymerizable polymer-coated fabrics which efficiently inactivate infectious viruses by contact with the *** is an opportune time to assess research efforts toward antimicrobial face mask technology for its expected impact on society and the economy.

关键词： gained Application coating

积云参数化和微物理方案不同组合应用对台风路径模拟效果的影响

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热带气象学报 2009年第4期25卷 435-441页

作者：河惠卿王振会金正润牛生杰徐爱淑江苏省气象灾害重点实验室/南京信息工程大学江苏南京210044 南京信息工程大学遥感学院江苏南京210044 韩国气象厅首尔156720 南京信息工程大学/大气物理与大气环境重点实验室江苏南京210044

利用美国国家环境预测中心(National Centers for Environmental Prediction,NCEP)和国家大气研究中心(NCAR)联合研发的天气研究和预报模式(Weather Research and Forecasting Model,WRF),研究了不同积云对流参数化方案和微物理过程方案对0514号台风"彩蝶"路径的影响。结果表明,积云对流参数化方案对台风路径影响较大,KF方案比BM方案能更好地模拟出台风路径;使用KF方案时,选择微物理方案比不选微物理方案对于台风路径有更好的模拟结果,其中,Ferrier、WSM6和Lin非常接近于实况;KF方案较好地模拟出副热带高压(简称副高)的西伸和东退的变化以及台风环流的风场分布和强度。

关键词：积云对流参数化方案微物理过程方案台风路径副高