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A Multi-Interface Remote Monitoring and Control System Architecture Based on Embedded Server

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Journal of Harbin Institute of Technology(New Series) 2013年第6期20卷 67-76页

作者： He liu Lei Wang Sheng-Peng Sun Ya-dong Wang Dep. of Biomedical Engineering Harbin Institute of Technology Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences Dep. of Measurement-Control Technology Harbin University of Science and Technology

This paper presents a multi-interface embedded server architecture for remote real-time monitoring system and distributed monitoring applications. In the scheme,an embedded microprocessor( LPC3250 from NXP) is chosen as the CPU of the embedded server with a linux operation system( OS) environment. The embedded server provides multiple interfaces for supporting various application scenarios. The whole network is based on local area network and adopts the Browser / Server( B / S) model. The monitoring and control node is as a browser endpoint and the remote node with an embedded server is as a server endpoint. Users can easily acquire various sensors information through writing Internet protocol address of remote node on the computer browser. Compared with client / server( C / S) mode,B / S model needs less maintain and can be applicable to large user group. In addition,a simple network management protocol( SNMP) is used for management of devices in Internet protocol( IP) networks. The results of the demonstration experiment show that the proposed system gives good support to manage the network from different user terminals and allows the users to better interact with the ambient environment.

关键词： muhi-interface remote monitoring and control embedded server simple network management protocol (SNMP)CLC number:TP216+.1 Document code:AArticle ID:1005-9113(2013)06-0067-10

Electromagnetic and microwave absorbing properties of FeCoB powder composites

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Rare Metals 2013年第4期32卷 402-407页

作者： Shen-Gen Zhang Hang-Xin Zhu Jian-Jun Tian De-An Pan bo liu Yan-Tao Kang Advanced Material and Technology Institute University of Science and Technology Beijing

The electromagnetic and microwave absorbing properties of FeCoB powder composites prepared by sin- gle-roller melt-spinning and mechanical milling processes were investigated in this paper. The result indicates that the flake-like powders are obtained. As milling time increases, the flake-like powder particles tend to agglomerate, causing the flake-like powders decrease gradually. The milling time plays an important role in the electromagnetic parameters which relates to the shape and size of the powder particles. The calculation shows that the sample milled for 6 h could achieve an optimal reflection loss of -11.5 dB at 5.8 GHz, with mass fraction of 83 % and a matching thickness of 1.8 mm. The result also indicates that the microwave absorbing properties of the FeCoB powder composites are adjustable by changing their thickness, and can be applied as a thinner microwave absorbing material in the range of 2-8 GHz.

关键词： Fe48Co48B4 powder composites Mechanical milling Electromagnetic parameters Microwave absorbing properties

Electrochemical behaviors of anode materials and their performance for bauxite desulfurization

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Chinese Journal of Chemical Engineering 2019年第4期27卷 802-810页

作者： Yingnan Hu Aijing Lü Mingyong Wang dong Wang Junhao liu Zhi Wang Xuzhong Gong National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Key Laboratory of Green Process and Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing 100083 China

Pyrite inside bauxite could be oxidized into soluble S-containing ions by electrolysis, and thus achieving bauxite desulfurization by using filtration. However, S-containing ions in electrolyte had some corrosion effects on electrode, especially for anode. In this work, six kinds of traditional materials were selected as anode, and their corrosion behaviors were examined by using electrochemistry characterization. Tafel and CV curves from simulating electrolyte suggested that their corrosion potentials were in the following order: Ni﹥C﹥SS﹥Fe﹥Cu﹥Pb–Ag. As expected, the desulfurization ratio and cell voltage from bauxite electrolysis were in the following order respectively: Cu﹥Ni﹥Fe﹥SS﹥C﹥Pb–Ag and Ni﹥Fe﹥SS﹥Cu﹥C﹥Pb–Ag. Finally, Ni was proposed a kind of excellent electrode material for bauxite desulfurization from electrolysis.

关键词： Corrosion resistance High sulfur bauxite Electrolysis desulfurization Electrode materials

Rapid and high precision measurement of opto-thermal relaxation with pump-probe method

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Science Bulletin 2018年第5期63卷 287-292页

作者： Tao Wang Xiao-Fei liu Yunqi Hu Guoqing Qin dong Ruan Gui-Lu Long State Key Laboratory of Low-Dimensional Quantum Physics and Department of Physics Tsinghua University Beijing 100084 China School of Science and the State Key Laboratory of Information photonics and Optical communications Beijing University of Posts and Telecommunications Beijing 100876 China Collaborative Innovation Centre of Quantum Matter Beijing 100084 China Tsinghua National Laboratoly of Information Science and Technology Beijing 100084 China

Opto-thermal relaxation is one of the most important properties of nonlinear optical *** and high precision measurement of this parameter is vital in both fundamental research and *** measurement uses either complicated structure with poor precision or high power heating source with low ***,we propose a pump-probe method(PPM) to optically measure the thermal relaxation using whispering gallery mode(WGM) *** the pump laser shines on a microcavity,the materials absorb the input power resonantly and heat *** the heat dissipates from the cavities to the *** opto-thermal effect induces a refractive index change reflected in the signal light transmission *** analyzing the curve character of the transmission spectra of the signal response in the spontaneous relaxation process,the thermal relaxation time can be rapidly measured with high ***,we systematically verify the PPM using microtoroids under various pump powers and at various locking points of the signal laser *** small rate of refractive index changes($10à8) can be discerned with an input pump power as low as 11.816 l ***,the PPM can be used to detect refractive index perturbation,like gas or liquid sensing,temperature fluctuations with ultra-high sensitivity and be applied to optical materials analysis efficiently.

关键词： Microcavities Opto-thermal effect Optical materials Thermal relaxation Sensing Pump-probe

Grain size refinement of additive manufactured Ce-TZP ceramics by coupled two-step pre-sintering and HIP

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Journal of Advanced Ceramics 2024年第5期13卷 621-629页

作者： Ruoshi Zhao Hongbing Yang Xintong liu Hezhen Li Chang-An Wang Jing Ma Yanhao dong State Key Lab of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Ceria-stabilized tetragonal zirconia polycrystal(Ce-TZP)has exceptional fracture toughness and flaw tolerance due to facile t‒m phase transformation ***,its wider-range applications are limited by its relatively low strength due to its large grain size and low transformation stress,which results in yield-like ***,we combined additive manufacturing(AM),pressureless two-step sintering,and hot isostatic pressing(HIP),and addressed the challenging grain size refinement problem in *** successfully produced dense ultrafine-grained Ce-TZP ceramics with an average grain size below 500 nm,a three-point bending strength above 800 MPa,and a single-edge-notch-beam fracture toughness in the range of 11‒12 MPa·m^(1/2).The critical roles of processing design,mixed Ce valences,and ***-stabilization of tetragonal polymorphs were *** work offers insights and strategies for the future development of stronger and tougher Ce-TZP ceramics that can compete with tetragonal yttria-stabilized zirconia in various applications,including additive manufacturing.

关键词： zirconia additive manufacturing(AM) two-step sintering hot isostatic pressing(HIP) grain size refinement

Investigation of lacrimal sac space-occupying lesions using color doppler ultrasound, computed tomography, and computed tomography dacryocystography

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International Journal of Ophthalmology(English edition) 2023年第8期16卷 1224-1230页

作者： Zhen-Bin Qian bo Yu Ye Yang Wei Fang Jian-Li dong Li-Qing Wei National Clinical Research Center for Ocular Diseases Eye HospitalWenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina Sijiqing Street Community Health Service Center Hangzhou 310000Zhejiang ProvinceChina

AIM:To observe the imaging features of color Doppler ultrasound(CDU)and computed tomography(CT)or computed tomography dacryocystography(CT-DCG)in different types of lacrimal sac space-occupying lesions(SOLs).METHODS:This retrospective case series study included 21 patients with lacrimal sac SOLs who underwent lacrimal sac surgery between January 2018 and March *** imaging features of CDU and CT or CT-DCG in these patients were extracted from the examination cloud *** images were observed and ***:The detection rate of lacrimal SOLs between CDU(21/21,100%)and CT or CT-DCG(20/21,95.2%)had no statistically significant difference(P=1.0).CDU could detect the blood flow signals in all SOLs except mucocele and mucopeptide *** them,polyps had characteristic imaging changes on CDU and *** mucoceles and mucopeptide concretions had characteristic imaging changes on CDU,which could provide more information for differential ***:The morphology and internal blood flow signals of lacrimal sac SOLs can be observed using *** or CT-DCG has advantages in observing structural damage around the lacrimal sac ***,CDU may be used as a routine examination to exclude lacrimal sac SOLs before dacryocystorhinostomy in the absence of preoperative CT or CT-DCG.

关键词： lacrimal sac computed tomography computed tomography dacryocystography color Doppler ultrasound space-occupying lesions

Control performance simulation and tests for Microgravity Active vibration Isolation System onboard the Tianzhou-1 cargo spacecraft

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Astrodynamics 2018年第4期2卷 339-360页

作者： Wei liu Yongkang Zhang Zongfeng Li Wenbo dong Key Laboratory of Space Utilization Technology and Engineering Center for Space UtilizationChinese Academy of SciencesBeijing100094China University of Chinese Academy of Sciences Beijing100049China

The Microgravity Active vibration Isolation System(MAIS),which was onboard China’s first cargo-spacecraft Tianzhou-1 launched on April 20,2017,aims to provide high-level microgravity at an order of 10^(-5)–10^(-6)g for specific scientific *** is mainly composed of a stator and a floater,and payloads are mounted on the *** relative motion with respect to the stator fixed on the spacecraft,the floater is isolated from vibration on the stator via control forces and torques generated by electromagnetic *** isolation results in a high-level microgravity *** MAIS was launched into space,its control performance had been simulated on computers and tested by air-bearing platform levitation and aircraft parabolic *** article first presents an overview of the MAIS’s hardware system,particularly system structure,measurement sensors,and control *** system dynamics,state estimation,and control laws are then discussed,followed by the results of computer simulation and engineering tests,including the test of the six-degree-of-freedom motion by aircraft parabolic *** and test results verify the accuracy of the control strategy design,effectiveness of the control algorithms,and performance of the entire control system,paving the way for operation of MAIS in *** article also presents the steps recommended for the control performance simulation and tests of MAIS-like *** devices are expected to be used on China’s Space Station for various scientific experiments that require a high-level microgravity environment.

关键词： Microgravity Active vibration Isolation System system dynamics modelling controller design vibration attenuation performance computer simulation air-bearing platform levitation aircraft parabolic flight

Tapping Carbon Sequestration Potential of Blooming Macroalgae to Mitigate Climate Change

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Ocean-Land-Atmosphere Research 2023年第1期2卷 359-363页

作者： Yongyu Zhang dong liu Nianzhi Jiao Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesQingdao 266101China Innovative Research Center for Carbon Neutralization Global ONCE ProgramXiamen UniversityXiamen 361005China Shandong Energy Institute Qingdao 266101China Qingdao New Energy Shandong Laboratory Qingdao 266101China Guangzhou Institute of Geochemistry Chinese Academy of SciencesGuangzhou 510640China

Macroalgal mariculture is gaining global attention to achieve carbon neutrality due to its important contribution to ocean carbon ***,some wild macroalgal species(e.g.,Sargassum and Ulva prolifera)exhibit strong environmental adaptability and can cause large-scale,recurrent blooms in global oceans,fueled by rising atmospheric CO_(2) levels and coastal ***,massive Ulva prolifera green tides have occurred annually in the Yellow Sea for the past 17 consecutive *** the late blooming stage,millions of tons of *** naturally sink to the shallow *** subsequent intense microbial aerobic degradation of sinking macroalgae results in coastal hypoxia and acidification,with most of the macroalgal carbon returning to the *** or reducing the intense degradation of massive sinking *** could enable more macroalgal carbon storage in the ocean in the long term and alleviate the harmful effects of green ***,ecological disasters from macroalgal blooms may be transformed into useful natural platforms to increase ocean carbon *** propose an integrated strategy using environmentally friendly minerals(e.g.,montmorillonite and calcium carbonate)and coagulants(e.g.,polyaluminum chloride),along with natural algicidal bacteria or substances,to induce rapid flocculation and sedimentation of blooming macroalgae,reduce the degradation of sinking macroalgae and its negative environmental impacts,and minimize the generation of macroalgal propagules or seeds and the potential risk for future green tide *** integrated approach is potentially a promising approach to tap the carbon sequestration potential of macroalgal blooms to mitigate climate change.

关键词： ocean coastal massive

On the drag reduction mechanism of hypersonic turbulent boundary layers subject to heated wall blowing

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Advances in Aerodynamics 2023年第1期5卷 126-148页

作者： Qiang liu Zhenbing Luo Yan Zhou Wei Xie Siwei dong College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China State Key Laboratory of Aerodynamics Mianyang 621000China

Turbulence drag reduction is of great significance for the range increase of hypersonic flight *** proposed velocity-temperature coupling control method(liu et al,Phys Rev Fluids 6:044603,2021)is further extended to the hypersonic turbulent boundary *** numerical simulation results of four comparative cases show that the heated wall blowing achieves a drag reduction rate of 10.58%,which is about the sum of wall blowing(5.27%)and wall heating(6.35%).By evaluating the control efficiency,however,it is found that heated wall blowing is not as good as wall blowing and cannot obtain net energy saving *** modified FIK decompositions of skin friction coefficient indicate that the cliffy decrease of the mean convection term is the primary contribution for the drag *** of the proposed control measure on turbu-lence statistics and coherent structures are also *** vortex is found to be away from the wall,thus leading to a lower friction drag.

关键词： Hypersonic turbulent boundary layer Turbulence drag reduction Velocity-temperature coupled control Turbulence statistics Turbulence structures Direct numerical simulations