检索结果-南通市图书馆

Capture-aware Bayesian RFID Tag Estimate for Large-scale Identification

在线全文

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2018年第1期5卷 119-127页

作者： haifeng wu Yang Wang Yu Zeng School of Electrical and Information Technology Yunnan Minzu University

Dynamic framed slotted Aloha algorithm is one of popular passive radio frequency identification(RFID) tag anticollision algorithms. In the algorithm, a frame length requires dynamical adjustment to achieve higher identification ***, the adjustment of the frame length is not only related to the number of tags, but also to the occurrence probability of capture effect. Existing algorithms could estimate both the number of tags and the probability of capture effect. Under large-scale RFID tag identification, however, the number of tags would be much larger than an initial frame length. In this scenario, the existing algorithm's estimation errors would substantially increase. In this paper, we propose a novel algorithm called capture-aware Bayesian estimate, which adopts Bayesian rules to accurately estimate the number and the probability simultaneously. From numerical results, the proposed algorithm adapts well to the large-scale RFID tag identification. It has lower estimation errors than the existing algorithms. Further,the identification efficiency from the proposed estimate is also higher than the existing algorithms.

关键词： Aloha Bayesian capture effect large-scale radio frequency identification(RFID)

A deep trench super-junction LDMOS with double charge compensation layer

在线全文

学校读者我要写书评

暂无评论

Journal of Semiconductors 2022年第10期43卷 103-108页

作者： Lijuan wu Shaolian Su Xing Chen Jinsheng Zeng haifeng wu Hunan Provincial Key Laboratory of Flexible Electronic Materials Genome Engineering School of Physics&Electronic ScienceChangsha University of Science&TechnologyChangsha 410114China

A deep trench super-junction LDMOS with double charge compensation layer(DC DT SJ LDMOS)is proposed in this *** to the capacitance effect of the deep trench which is known as silicon-insulator-silicon(SIS)capacitance,the charge balance in the super-junction region of the conventional deep trench SJ LDMOS(*** SJ LDMOS)device will be broken,resulting in breakdown voltage(BV)of the device *** DT SJ LDMOS solves the SIS capacitance effect by adding a vertical variable doped charge compensation layer and a triangular charge compensation layer inside the *** SJ LDMOS ***,the drift region reaches an ideal charge balance state *** electric field is optimized by double charge compensation and gate field plate so that the breakdown voltage of the proposed device is improved sharply,meanwhile the enlarged on-current region reduces its specific *** simulation results show that compared with the *** SJ LD-MOS,the BV of the DC DT SJ LDMOS has been increased from 549.5 to 705.5 V,and the R_(on,sp) decreased to 23.7 mΩ·cm^(2).

关键词： double charge compensation layer super-junction deep trench SIS capacitance

Homogenization Function of Microchannel on Heat Absorber with Compound Parabolic Concentrator

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2022年第6期31卷 2022-2031页

作者： WANG Xueqing wu haifeng MA Yusen WANG Suilin XU Rongji Beijing Engineering Research Center of Sustainable Energy and Buildings Beijing University of Civil Engineering and ArchitectureBeijing 100044China

Microchannels offer unique advantages on heat transfer performance. In this paper, microchannels are applied to the compound parabolic concentrator(CPC) system. A multi-physical field coupling model based on Finite Element Method is proposed to investigate the homogenization effect of the microchannel heat absorber on the CPC non-uniform concentration. The energy conversion process from optics to heat is simulated using TracePro software, and the heat transfer processes in the microchannel are computed by Fluent using user defined functions(UDF). It is found that the microchannels behave well on weakening the influence of the nonuniformity solar heat flux on the performance of the CPC. The temperature nonuniformity of the outlet section is less than 10^(-3) in the direction of fluid flow caused by the microchannel, although the maximum surface heat flux inhomogeneity of the microchannel reaches 2.3. The peak value of the heat flux on the surface of the absorber changes from double peak to single peak, and moves to the edge, resulting in more uneven heat flux distribution with the increase of the incident angle within the acceptance semi-angle of the CPC. The result of TracePro clearly shows that when the concentration ratio is less than 5, the heat flux nonuniformity on the surface of the absorber decreases with the increase in concentration ratio. It was interestingly found that the temperature distribution of the heat transfer fluid has weak sensitivity to the changes of truncation ratio. This work provides a way to design a CPC solar collector.

关键词： solar energy microchannel compound parabolic concentrator multi-physical field

Integration of a thermochemical energy system driven by solar energy and biomass for natural gas and power production

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2022年第6期65卷 1383-1395页

作者： wu haifeng ZHANG BoWen QU WanJun XU RongJi LIU QiBin Beijing Engineering Research Center of Sustainable Energy and Buildings Beijing University of Civil Engineering and ArchitectureBeijing 100044China Guangdong Provincial Key Laboratory of Distributed Energy Systems School of Chemical Engineering and Energy TechnologyDongguan University of TechnologyDongguan 523808China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Energy systems with multi-energy product outputs driven by renewable energy sources are becoming increasingly *** satisfy the diversification of energy use forms in China,this study proposes a new thermochemical energy system driven by solar energy and biomass for natural gas and power *** this system,syngas from solar-driven biomass gasification is used to synthesize natural gas,whereas the unreacted syngas is burned directly in a combined cycle for power *** adjust the production capacity of the system,a shift reaction was used to change the H_(2)/CO ratio in the *** biomass gasification model was experimentally verified,and the thermodynamic performance of the system was studied *** results showed that the production rate of natural gas,with a heat value of 714.88 k J/mol,was approximately 0.306 m^(3)-SNG/kg-bio,and the primary energy efficiency was 47%.The new system showed a good energy-saving potential of 15.29%.Parametric analysis indicated that an increase in the gasification temperature led to a reduction in the natural gas production and an increase in the power output of the system,with a maximum energy efficiency of 66.72%at gasification temperature of 1050°*** an increase in the syngas share entering the transfer reactor,the natural gas production rate and energy efficiency of the system were improved with an optimum share of approximately 0.55,thereby facilitating the development and optimization of operation *** study provides a promising way to increase the share of renewable energy instead of fossil fuels.

关键词： solar energy biomass gasification natural gas thermochemical energy system thermodynamics performance

同方期刊数据库

Designed histidine-rich peptide self-assembly for accelerating oxidase-catalyzed reactions

在线全文

学校读者我要写书评

暂无评论

Nano Research 2022年第5期15卷 4032-4038页

作者： Peidong Du Siyuan Liu Hao Sun haifeng wu Zhen-Gang Wang State Key Laboratory of Organic-Inorganic Composites Key Lab of Biomedical Materials of Natural Macromolecules(Beijing University of Chemical TechnologyMinistry of Education)Beijing Laboratory of Biomedical MaterialsBeijing University of Chemical TechnologyBeijing 100029China

It is an important goal for supramolecular chemistry to develop synthetic enzyme mimics rivaling native enzymes,while de novo fabrication of such mimics remains a ***,the catalytic groups from the supramolecular complex can be integrated with the active sites of natural ***,we present a supramolecular catalytic hybrid that is self-assembled from oligohistidine-based peptides and a heme-dependent *** results indicate that the peptides altered the enzyme conformation,promoted the transitions between the resting and the intermediate states of the heme,and increased the turnover rate of the enzyme by up to *** propose that the histidine residues from the peptides may collaborate with the groups in the natural heme pocket to accelerate the catalytic cycles of the *** observations underline the advantages of the supramolecular approach and suggest that molecular self-assembly may combine with enzymes to provide a simple strategy to engineer the enzymatic active sites.

关键词： self-assembly oligohistidine enzymes biocatalysis active site

Power Generation Enhancement in a Solar Energy and Biomass-Based Distributed Energy System using H_(2)O/CO_(2)Hybrid Gasification

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Thermal Science 2024年第5期33卷 1657-1671页

作者： wu haifeng LYU Yan WANG Ruixiang XU Rongji QU Wanjun LIU Qibin Beijing Engineering Research Center of Sustainable Energy and Buildings Beijing University of Civil Engineering and ArchitectureBeijing 100044China Guangdong Provincial Key Laboratory of Distributed Energy Systems School of Chemical Engineering and Energy TechnologyDongguan University of TechnologyDongguan 523808China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China

A new solar energy and biomass-based distributed energy system using H_(2)O/CO_(2)hybrid gasification is proposed,and their complementarity to enhance the system's energy efficiency is investigated and *** the system,concentrated solar energy is used to provide heat for biomass gasification;two gasifying agents(H_(2)O and CO_(2))are adopted to enhance syngas yields,and the produced solar fuel is further burned for power production in a combined cycle *** show that CO share in gasification products is remarkably increased with the increment of CO_(2)/H_(2)O mole ratio caused by the boudouard reaction with the consumption of fixed carbon,while the H_(2)share is decreased;the optimal solar-to-fuel efficiency,27.88%,is achieved when the temperature and CO_(2)/H_(2)O mole ratio are 1050℃and 0.45,*** emission reduction rate of CO_(2)in the system under design conditions is reduced by 2.31%compared with that using only H_(2)O *** annual power production of the system is increased by 1.39%,and the thermodynamic and environmental performances are significantly ***,an economic assessment is conducted to forecast the technical feasibility of the hybrid gasification *** work provides a promising route to improving the thermochemical utilization efficiency of solar energy and solid fuel.

关键词： solar energy biomass hybrid gasification distributed energy system thermodynamics performance

Designed imidazole-based supramolecular catalysts for accelerating oxidation/hydrolysis cascade reactions

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第6期17卷 4916-4923页

作者： Yuanxi Liu Wenjie Xu Shichao Xu haifeng wu Baoli Zhang Li Song Zhen-Gang Wang State Key Laboratory of Organic-Inorganic Composites Key Lab of Biomedical Materials of Natural Macromolecules(Ministry of Education)Beijing Laboratory of Biomedical MaterialsCollege of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China National Synchrotron Radiation Laboratory CAS Center for Excellence in NanoscienceUniversity of Science and Technology of ChinaHefei 230029China

Reconstructing enzymatic active sites presents a significant challenge due to the intricacies involved in achieving enzyme-like scaffold folding and spatial arrangement of essential functional *** is also a growing interest in building biocatalytic networks,wherein multiple enzymatic active sites are localized within a single artificial system,allowing for cascaded *** this work,we report the self-assembly of imidazole or its derivatives with fluorenylmethyloxycarbonyl-modified histidine and Cu2+to fabricate a supramolecular catalyst,which possesses catechol oxidase-like dicopper center with multiple imidazole as the coordination *** electron microscopy,low-temperature X-band continuous-wave electron paramagnetic resonance,K-edge X-ray absorption spectra/the extended X-ray absorption fine structure analysis,and density functional theory modeling were used for the structural characterization of the *** phenol derivatives and the dissolved oxygen were used as the substrates,with the addition of 4-aminoantipyrine to generate a red adduct with a maximum absorbance at 510 nm,for obtaining time-dependent absorbance change curves and estimating the *** results reveal that the addition of imidazole synergistically accelerates the oxidative activity about 10-fold and the hydrolysis activity about 14-fold than fluorenylmethyloxycarbonyl modified-histidine/Cu2+.The supramolecular nanoassembly also exhibits the ability to catalyze oxidation/hydrolysis cascade reactions,converting 2′,7′-dichlorofluorescin diacetate into 2′,7′-*** process can be regulated through the methylation of the imidazole component at various *** work may contribute to the design of advanced biomimetic catalysts,and shed light on early structural models of the active sites of the primitive copper-dependent enzymes.

关键词： enzyme mimic self-assembly supramolecular catalyst cascade reactions

The frequency and skewed T-cell receptor beta-chain variable patterns of peripheral CD4＋CD25＋ regulatory T-cells are associated with hepatitis B e antigen seroconversion of chronic hepatitis B patients during antiviral treatment

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Cellular & Molecular Immunology 2016年第5期13卷 678-687页

作者： Jiezuan Yang Guoping Sheng Dangsheng Xiao Haiyan Shi Wei wu haifeng Lu Ping Yi Hongcui Cao Lanjuan Li State Key Laboratory for Diagnosis and Treatment of Infectious Diseases Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases The First Affiliated Hospital College of Medicine Zhejiang University Hangzhou 310003 Zhejiang Province PR China

The frequency and T-cell receptor beta-chain variable （TCRBV） patterns of peripheral CD4＋CD25＋ regulatory T-cells （Tregs） are ambiguously altered in chronic hepatitis B （CHB） patients following tenofovir disoproxil fumarate （TDF） treatment. Moreover, the clinical significance of these parameters in relation to hepatitis B e antigen （HBeAg） seroconversion （SC） is largely unknown. In this study, the circulation of Tregs in HBeAg-positive CHB patients was determined by flow cytometry, and the molecular profiles of frequent TCRBV patterns of Tregs were analyzed using a gene melting spectral pattern. The parameters, such as Treg frequency, the number of skewed TCRBV patterns, hepatitis B virus （HBV） DNA levels, and alanine aminotransferase （ALT） levels, were analyzed by comparing their associations in seroconverting and non-seroconverting patients following TDF treatment. The Treg frequency was significantly correlated with the ALT level in seroconverting but not in non-seroconverting patients. Similarly, skewed TCRBV patterns were remarkably associated with HBV DNA levels in the SC group. Six TCRBV families （BV3, BV11, BV12, BV14, BV20, and BV24） were more prevalent than other TCRBV members in seroconverting patients pretreated with TDF, while BV12, BV15, and BV22 were predominant in non-seroconverting patients during TDF treatment. Taken together, the preferential TCRBV patterns may be associated with immune responses related to SC. The dynamic frequency and skewed TCRBV patterns of peripheral Tregs could contribute to predicting SC in CHB patients. Moreover, the conserved TCRBV complementarity-determining region （CDR3） motif may be targeted to develop personalized immunotherapy for CHB patients.

关键词： chronic hepatitis B individual treatment gene melting spectral pattern regulatory T-cells T-cell receptorbeta-chain variable

A 0.1–1.5 GHz multi-octave quadruple-stacked CMOS power amplifier

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Semiconductors 2020年第6期41卷 44-47页

作者： Shizhe Wei haifeng wu Qian Lin Mingzhe Zhang School of Microelectronics Tianjin UniversityTianjin 300072China Chengdu Ganide Technology Chengdu 610073China College of Physics and Electronic Information Engineer Qinghai University for NationalitiesXining 810007China

In this letter,we design and analyze 0.1–1.5 GHz multi-octave quadruple-stacked CMOS power amplifier(PA)in 0.18μm CMOS *** using two-stage quadruple-stacked topology and feedback technology,the proposed PA realizes an ultra-wideband CMOS PA in a small chip *** impedance matching is achieved with smaller chip *** effects of feedback resistors on the RF performance are also discussed for this stacked-FET *** PA shows measured input return loss(<–10.8 dB)and output return loss(<–9.6 dB)in the entire bandwidth.A saturated output power of 22 dBm with maximum 20%power added efficiency(PAE)is also measured with the drain voltage at 5 *** chip size is 0.44 mm^2 including all pads.

关键词： power amplifier CMOS stacked multi-octave resistive matching