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Frontiers of Environmental Science & Engineering 2024年第7期18卷 73-85页

作者： Sanggwon An Sangsoo Choi Hyeong Rae Kim Jungho Hwang School of Mechanical Engineering Yonsei UniversitySeoul 02876Republic of Korea gas metrology group Korea Research Institute of Standards and Science(KRISS)Daejeon 34113Republic of Korea

The World Health Organization has raised concerns about the possibility of airborne transmission in enclosed and poorly ventilated ***,rapid monitoring of airborne viruses is necessary in multi-use facilities with dense ***,an electrostatic air sampler(250 L/min)was developed in this work to obtain indoor viral aerosol samples for analysis via the Polymerase Chain Reaction(PCR).Aerosol tests with H1N1 and HCoV-229E were performed to evaluate the sample collection *** analysis,along with another aerosol test,was conducted to evaluate the recovery of the virus particles collected by the *** laboratory tests,our electrostatic sampler obtained viral samples that were detectable by PCR under the simulated viral pandemic scenario(3000 RNA copies per cubic meter of air)within 40 *** resulting cycle threshold(C)values were 35.07 and 37.1 for H1N1 and HCoV-229E,*** the performance evaluation in the laboratory,field tests were conducted in a university classroom from October 28 to December 2,*** A and HCoV-229E were detected in two air samples,and the corresponding C,values were 35.3 and *** PCR results are similar to those obtained from laboratory tests,considering the simulatedviralpandemic scenario.

关键词： Airborne virus Electrostatic sampler Rapid monitoring Indoor environment Field test

High Conversion Efficiency and Power Stability of 532 nm Generation from an External Frequency Doubling Cavity

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Chinese Physics Letters 2012年第9期29卷 87-89页

作者： ZHAO Yang LIN Bai-Ke LI Ye ZHANG Hong-Xi CAO Jian-Ping FANG Zhan-Jun LI Tian-Chu ZANG Er-Jun Division of Time and Frequency metrology National Institute of MetrologyBeijing 100013 Department of Precision Instruments and Mechanology Tsinghua UniversityBeijing 100084 st Instruments of China Electronics Technology group Corporation Qingdao 266555

We present a high-efficiency 532 nm green light conversion from an external cavity-enhanced second harmonic generation(SHG)with a periodically poled KTP crystal(PPKTP).The cavity is a bow-tie ring configuration with a unitized *** the impedance matching is optimized,the coupling efficiency of the fundamental is as high as 95%.Taking into account both the high power output of the second harmonic and the stability of the system,we obtain over 500 mW green passing through the output cavity mirror,corresponding to a net conversion efficiency higher than 75.2%.Under these operating conditions,the power stability is better than±0.25%during 5 *** is the highest conversion efficiency and power stability ever produced in the bow-tie ring cavity with PPKTP for 532 nm generation.

关键词： Efficiency cavity stability

Preprocessing of 2-Dimensional Gel Electrophoresis Images Applied to Proteomic Analysis： A Review

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Genomics, Proteomics & Bioinformatics 2018年第1期16卷 63-72页

作者： Manuel Mauricio Goez Maria Constanza Torres-Madronero Sarah Rothlisberger Edilson Delgado-Trejos Automatics Electronics and Computer Science Research Group Faculty of Engineering Instituto Tecnologico Metropolitano Medellin 050012 Colombia Biomedical Innovation and Research group Faculty of Applied and Exact Sciences lnstituto Tecnologico Metropolitano Medellin 050012 Colombia Quality Metrology and Production Research Group Faculty of Economic and Management Sciences Instituto Tecnologico Metropolitano Medellin 050012 Colombia

Various methods and specialized software programs are available for processing two- dimensional gel electrophoresis （2-DGE） images. However, due to the anomalies present in these images, a reliable, automated, and highly reproducible system for 2-DGE image analysis has still not been achieved. The most common anomalies found in 2-DGE images include vertical and hor- izontal streaking, fuzzy spots, and background noise, which greatly complicate computational anal- ysis. In this paper, we review the preprocessing techniques applied to 2-DGE images for noise reduction, intensity normalization, and background correction. We also present a quantitative comparison of non-linear filtering techniques applied to synthetic gel images, through analyzing the performance of the filters under specific conditions. Synthetic proteins were modeled into a two-dimensional Gaussian distribution with adjustable parameters for changing the size, intensity, and degradation. Three types of noise were added to the images： Gaussian, Rayleigh, and exponen- tial, with signal-to-noise ratios （SNRs） ranging 8-20 decibels （dB）. We compared the performanceof wavelet, contourlet, total variation （TV）, and wavelet-total variation （WTTV） techniques using parameters SNR and spot efficiency. In terms of spot efficiency, contourlet and TV were more sen- sitive to noise than wavelet and WTTV. Wavelet worked the best for images with SNR ranging 10- 20 dB, whereas WTTV performed better with high noise levels. Wavelet also presented the best per- formance with any level of Gaussian noise and low levels （20-14 dB） of Rayleigh and exponential noise in terms of SNR. Finally, the performance of the non-linear filtering techniques was evaluated using a real 2-DGE image with previously identified proteins marked. Wavelet achieved the best detection rate for the real image.

关键词： Background correction Filtering Noise reduction Preprocessing 2D gel electrophoresis

A New Approach to State Estimation for Uncertain Linear Systems in a Moving Horizon Estimation Setting

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International Journal of Automation and computing 2016年第6期13卷 653-664页

作者： J.Garcia-Tirado H.Botero F.Angulo Faculty of Economic and Administrative Sciences QualityMetrology and Production Research GroupMetropolitan Institute of Technology of Medellin (ITM) KALMAN Research group Faculty of MinesElectric Energy and Automatics DepartmentNational University of Colombia (MedelliCampus) Perception and Intelligent Control Research group Department of ElectricalElectronicsand Computational EngineeringFaculty of Engineering and ArchitectureNational University of Colombia (Manizales)Q buildingLa Nubia campus

This paper addresses the state estimation problem for linear systems with additive uncertainties in both the state and output equations using a moving horizon approach. Based on the full information estimation setting and the game-theoretic approach to the H∞filtering, a new optimization-based estimation scheme for uncertain linear systems is proposed, namely the H∞-full information estimator, H∞-FIE in short. In this formulation, the set of processed data grows with time as more measurements are received preventing recursive formulations as in Kalman filtering. To overcome the latter problem, a moving horizon approximation to the H∞-FIE is also presented, the H∞-MHE in short. This moving horizon approximation is achieved since the arrival cost is suitably defined for the proposed scheme. Sufficient conditions for the stability of the H∞-MHE are derived. Simulation results show the benefits of the proposed scheme when compared with two H∞filters and the well-known Kalman filter.

关键词： uncertain processed overcome estimator latter horizon filtering recursive weighting constraints

LES Analysis of the Unsteady Flow Characteristics of a Centrifugal Pump Impeller

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Fluid Dynamics & Materials Processing 2022年第5期18卷 1349-1361页

作者： Ting Zhang Denghao Wu Shijun Qiu Peijian Zhou Yun Ren Jiegang Mou School of metrology and Measurement Engineering China Jiliang UniversityHangzhouChina Leo group Pump Co. Ltd.TaizhouChina Zhijiang College Zhejiang University of TechnologyHangzhouChina

Stall phenomena increase the complexity of the internal flow in centrifugal pump *** order to tackle this problem,in the present work,a large eddy simulation(LES)approach is applied to determine the characteristics of these unstable ***,a vorticity identification method is used to characterize quantitatively the vortex position inside the impeller and its influencing *** comparing the outcomes of the numerical simulations and experimental results provided by a Particle Image Velocimetry(PIV)technique,it is shown that an apparent“alternating stall”phenomenon exists inside the impeller when relatively small flow rate conditions are *** stall is generated near the suction side of the blade inlet,grows towards the high-pressure side of the blade in the circumferential direction,and gradually *** the flow rate decreases,the number of stalls remains unchanged,while the related influencing area and strength gradually increase and the circumferential velocity increases.

关键词： Centrifugal pump impeller large eddy simulation unsteady flow stalls vorticity

Investigation of the crystal structure and magnetic properties of Nd_(3-x)GdxCo_(11)B_4 borides

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Journal of Rare Earths 2011年第5期29卷 466-470页

作者： Seluk Kervan Nazmiye Kervan Ayse zdemir Hseyin Szeri Nevsehir University Faculty of Arts and SciencesPhysics Department TUBTAK-UME National Metrology Institute

Polycrystalline samples of pseudo-ternary intermetallic Nd3–xGdxCo11B4 （x=0,1,2,3） borides prepared by standard arc-melting were characterized by X-ray powder diffraction （XRPD）,magnetization and differential scanning calorimetry （DSC） measurements. The X-ray diffraction patterns indicated the hexagonal Ce3Co11B4-type structure with P6/mmm space group for each composition. The substitution of Gd for Nd led to a decrease of the unit-cell parameters a and the unit-cell volume V,while the unit-cell parameter c increased linearly. Magnetic measurements indicated that all samples were ordered magnetically below the Curie temperature. The Curie temperatures increased as Nd was substituted by Gd. The saturation magnetization at 4 K decreased upon the Gd substitution up to x=1,and then increased.

关键词： intermetallics magnetically ordered materials magnetic measurements rare earths

Coating zirconium oxide-nanocomposite with humic acid for recovery of mercury and chromium in hazardous waste of chemical oxygen demand test

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Journal of Environmental Sciences 2023年第4期126卷 40-47页

作者： Yujian Lai Liteng Hao Lijie Dong Sujuan Yu Jingfu Liu State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China China Testing&Certification International group Co. Ltd.Beijing 100024China School of Environment Hangzhou Institute for Advanced StudyUCASHangzhou 310024China Division of Chemical metrology and Analytical Chemistry National Institute of MetrologyBeijing 100029China Institute of Environment and Health Jianghan UniversityWuhan 430056China

Hazardous waste of chemical oxygen demand (COD) test (HWCOD) is one of the most common laboratory wastewaters,containing large amounts of H_(2)SO_(4)and highly toxic Cr^(3+)and Hg^(2+).Current treatment methods suffered from incomplete removal of Cr^(3+)and ***,a humic acid-coated zirconium oxide-resin nanocomposite (HA-HZO-201) was fabricated for efficient recovery of Cr^(3+)and Hg^(2+)in *** synthesized HA-HZO-201 shows excellent tolerance to wide p H range (1–5) and high salinity (3.5 mol/L Na Cl),as well as adsorption capacity for Cr^(3+)(37.5 mg/g) and Hg^(2+)(121.3 mg/g).After treating with HA-HZO-201 by using a fixed-bed adsorption procedure,the final Cr^(3+)and Hg^(2+)concentrations in HWCOD decreased to 0.28 and 0.02 mg/L,*** addition,the HA-HZO-201 can be regenerated by desorption and recovery of Cr^(3+)and Hg^(2+)using HNO_(3)and thiourea as eluents,*** 5 cycles of adsorption/desorption,the removal efficiencies still reach up to86.0%for Cr^(3+)and 89.7%for Hg^(2+),indicating an excellent regeneration of *** hope this work open new opportunities for treatment of HWCODwith high-efficiency and low-cost.

关键词： COD analysis wastewater Nanocomposite ZrO_(2) Resin Humic acid

Gain flattened distributed fiber raman amplifiers

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Optoelectronics Letters 2007年第5期3卷 339-341页

作者： ZHANG Zai-xuan DAI Bi-zhi WANG Jian-feng LIU Hong-lin XU Hai-feng GENG Dan LI Lan-xiao LI Chen-xia INSOO S. KIM Optoelectronics Technology Institute China Metrology University Hangzhou 310018 China Optical Technology Research group Korea Electrotechnology Research Institute Seoul 437-808 Korea

An S band and a C band distributed fiber Raman amplifiers (DFRAs) with flattened gain and compensated dispersion have been studied and implemented with 1427 nm and 1455 nm mono-wavelength fiber Raman lasers as the pumped sourcesrespectively. The gain of single-wave pumped S band and C band can reach 10 dB and 15 dB respectively. And a 50 nmgain flattened width was successfully obtained by using a chirp fiber Bragg grating (CFBG) gain flattened filter with gainripple of ±0.6 dB. The C band DFRA has been applied to CDMA wireless communication system successfully.

关键词：光学纤维拉曼放大器 DFRAs 补偿作用

The long range distributed fiber raman photon temperature sensor

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Optoelectronics Letters 2007年第6期3卷 404-405页

作者： ZHANG Zai-xuan WANG Jian-feng LIU Hong-Iin XU Hai-fen DAI Bi-zhi LI Chen-xla LI Lan-xiao GENG Dan INSOO S. KIM Optoelectronics Technology Institute China Metrology University Hangzhou 310018 China Optical Technology Research group Korea Electrotechnology Research Institute Seou1437-808 Korea

A 31 km long range distributed optical fiber Raman photon temperature sensor (DOFRPTS) system have been developed based on temperature effect of the amplified spontaneous Raman scattering in fiber, and using fiber laser as a pumped source. The results show that temperature measuring uncertainty is ±2 °C, temperature resolution is 0.1 °C, measurement time is 432 s, spatial resolution is less than 4 m.

关键词：照片传感器光纤元件纤维分布

Design of a device for precision shaping of grinding wheel macro-and micro-geometry

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Journal of Central South University 2012年第1期19卷 135-143页

作者： Krzysztof NADOLNY Wojciech KAPLONEK Department of Production Engineering Faculty of Mechanical EngineeringKoszalin University of TechnologyRacIawicka 15-1775-620 KoszalinPoland Subject group of metrology and Quality Faculty of Mechanical EngineeringKoszalin University of TechnologyRacIawicka 15-1775-620 KoszalinPoland

The selected modifications to the construction of grinding wheels were described which facilitate an increase in the material removal rate （grinding wheels with conic chamfer and grinding wheels with microdiscontinuities on the active surface）. Using these background details, a suggested thesis was put forward regarding the need to develop a device which will allow for the shaping of the macrogeometry of the grinding wheel （cylindrical and conical surfaces） and the microdiscontinuities within the dressing operation simultaneously. The device was presented and prepared in two functional variants （horizontal and vertical mounting of the motor）, then a prototype was described. An example of the grinding wheel active surface, shaped by using this device, was also presented. The theoretical analysis and experimental verification performed determine that the error of shaping the conic chamfer angle within the range of 0-1.5°, using the developed device, is approximately ±3%.

关键词： single-pass grinding dressing grinding wheels with conic chamfer microdiscontinuities of grinding wheel