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Detecting differences in volume pulse wave parameters among fingers and toes in four different postures

BIO-MEDICAL MATERIALS AND ENGINEERING 2015年第Sup1期26卷 S389-S394页

作者： Yan, Tingting Yang, lin Zhang, Song Yang, Yimin li, xuwen Beijing Univ Technol Coll Life Sci & Bioengn 100 Ping Le Yuan Beijing 100124 Peoples R China

The measurement of volume pulse waves may be easily affected based on the measured position (different fingers or toes), body posture, as well as other factors. Therefore, interferences during measurement need to be removed. For this study, relevant parameters of volume pulse wave were obtained by changing the affecting factors. The data were analyzed in order to indicate the differences in volume pulse wave parameters among different fingers and toes in four postures. Results showed that when subjects were lying, inclined or in a sitting posture, volume pulse wave parameters of the index finger, middle finger and ring finger on both hands displayed no apparent differences. When subjects were in a sitting posture, volume pulse wave parameters of the big, second and third toes on both feet showed no significant differences.

关键词： Photoplethysmography volume pulse wave parameters different postures

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A new self-tuning Kalman filter for tracking abrupt input change

A new self-tuning Kalman filter for tracking abrupt input ch...

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2nd Annual Conference on Electrical and Control Engineering, ICECE 2011

作者： li, xuwen Wu, Qiang Wu, Shuicai College of Life Science and Bio-engineering Beijing University of Technology Beijing China College of Electronic Information and Control Engineering Beijing University of Technology Beijing China

ISBN: (纸本)9781424481637

This paper proposes a new self-tuning Kalman filter with good tracking ability for unknown noise statistics and unknown abrupt input change. The new filter can easily compute unknown abrupt input and steady-state gain matrix by building up online identification of ARMAX innovation model in real time. The simulation results of tracking a maneuvering target shows the effectiveness of the new method in this paper. © 2011 IEEE.

关键词： Kalman filters

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Dependence of the liquid crystalline properties on the exactly controlled single-site functionalized density of mesogens focused on the alternating copolymer model

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POLYMER CHEMISTRY 2021年第45期12卷 6561-6568页

作者： Zhang, Ruixue li, xuwen Ma, Hongwei Han, li li, Chao Zhang, Songbo Bai, Hongyuan li, Yang Dalian Univ Technol Sch Chem Engn Dept Polymer Sci & Engn State Key Lab Fine Chem Dalian 116024 Peoples R China

Fluorinated liquid crystal polymers (FLCPs) with an AB/A(2)B-alternating sequence of fluorinated biphenyl moieties (FMs) along their backbones were constructed, where the anionic copolymerization of isoprene (Ip) with, mono-SiH and di-SiH functionalized 1,1-diphenylethylene (DPE) derivatives was performed to prepare alternating copolymer precursors with exactly controlled single-site densities of -SiH, i.e., alt-P(D-S/Ip) and alt-P(D-2S/Ip), respectively, followed by highly efficient hydrosilylation to introduce FMs into the repeating unit (DPE). Previous work indicated that the mesogenic properties were related to the distance between neighbouring mesogenic moieties in different polymerized units when the degree of polymerization (DP) of the copolymers was low. Hence, the present strategy provides a novel model to explore dependence of the mesogenic properties on the exactly controlled single-site functionalized density of mesogens (FMs) for the resulting alternating-templated FLCPs, which was achieved due to a quite low DP (11 for mono-SiH and 5 for di-SiH), while exhibiting a similar overall concentration of FMs along backbones bearing a similar number of Si-H groups. The results show that the polarized optical textures and the temperature range of mesogenic phase formation (Delta T) varied remarkably between A(2)B-alternating (Delta T = 104 degrees C) and AB-alternating (Delta T = 23 degrees C) FLCPs;in particular, the variation in phase transition temperature is possibly a result of exactly controlled single-site functionalized density. Herein, a novel morphological aggregation model is proposed to increase the comprehension of how the exactly controlled single-site functionalized density of FMs arranged within the small scale of polymer chains directs molecular packing and interactions between them, thereby enriching the diversity of molecular interactions.

关键词： Silicon compounds

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Sensitive determination of three aconitum alkaloids and their metabolites in human plasma by matrix solid-phase dispersion with vortex-assisted dispersive liquid-liquid microextraction and HPLC with diode array detection

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JOURNAL OF SEPARATION SCIENCE 2016年第10期39卷 1971-1978页

作者： Wang, Xiaozhong li, xuwen li, Lanjie li, Min liu, Ying Wu, Qian li, Peng Jin, Yongri Jilin Univ Coll Chem Changchun 130012 Peoples R China Ningxia Univ Sch Chem & Chem Engn Yinchuan Peoples R China

A simple and sensitive method for determination of three aconitum alkaloids and their metabolites in human plasma was developed using matrix solid-phase dispersion combined with vortex-assisted dispersive liquid-liquid microextraction and high-performance liquid chromatography with diode array detection. The plasma sample was directly purified by matrix solid-phase dispersion and the eluate obtained was concentrated and further clarified by vortex-assisted dispersive liquid-liquid microextraction. Some important parameters affecting the extraction efficiency, such as type and amount of dispersing sorbent, type and volume of elution solvent, type and volume of extraction solvent, salt concentration as well as sample solution pH, were investigated in detail. Under optimal conditions, the proposed method has good repeatability and reproducibility with intraday and interday relative standard deviations lower than 5.44 and 5.75%, respectively. The recoveries of the aconitum alkaloids ranged from 73.81 to 101.82%, and the detection limits were achieved within the range of 1.6-2.1 ng/mL. The proposed method offered the advantages of good applicability, sensitivity, simplicity, and feasibility, which makes it suitable for the determination of trace amounts of aconitum alkaloids in human plasma samples.

关键词： Aconitum alkaloids Dispersive liquid-liquid microextraction Human plasma Matrix solid-phase dispersion

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Anti-rotation GNSS signal tracking algorithm based on symmetric dual antennas 22

Anti-rotation GNSS signal tracking algorithm based on symmet...

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8th International Conference on Computing and Artificial Intelligence, ICCAI 2022

作者： Zhang, Haidong li, xuwen Wu, Qiang Beijing University of Technology Information Department Beijing China

ISBN: (纸本)9781450396110

Due to periodic occlusion caused by rotating vehicles, the antenna cannot continuously receive GNSS signal. At the same time, the Doppler frequency shift caused by rotation also brings additional influence on GNSS signal tracking by the vehicles. This paper proposes a GNSS signal tracking algorithm based on dual antennas. The algorithm realizes the continuous and stable tracking of GNSS signal by signal preprocessing of symmetric dual antenna and joint calculation. Simulation results show that the algorithm can effectively reduce the influence of rotation on GNSS tracking PLL and improve the stability of tracking process. © 2022 ACM.

关键词： Rotation

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The Influenceof Rare Earth Element on α-Solidification of A356 Alloy

The Influenceof Rare Earth Element on α-Solidification of A...

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International Conference on Advances in Materials and Manufacturing Processes

作者： Zheng, Zhiqiang Xiong, Xingen Chen, Keming li, xuwen Nanchang Univ Nanchang 330031 Peoples R China

ISBN: (纸本)9780878492039

The Influenceof Rare Earth Element on alpha-Solidification of A356 Alloy has been discussed in the paper. It is showed by the research, that the condition of interphase is changed by Rare Earth element asymmetry distribution, which influences the process of a phase growing and facilitates the growth of alpha phase in sphere, and leads to a optimal Rare Earth quantity for facilitative effect, which is 0.5% in this experimentation, and that alpha phase grain will be change to small by adding Rare Earth.

关键词： semi-solid aluminum silicon alloy solidify Rare Earth

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The antiallergic activity of flavonoids extracted from Citri Reticulatae Pericarpium

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JOURNAL OF FOOD PROCESSING AND PRESERVATION 2018年第4期42卷 e13588-e13588页

作者： Shi, Xiaolei Niu, liyan Zhao, lina Wang, Bo Jin, Yongri li, xuwen Jilin Univ Dept Food Qual & Safety Coll Food Sci & Engn Changchun 130062 Jilin Peoples R China Jilin Univ Dept Analyt Chem Coll Chem Changchun 130012 Jilin Peoples R China

The fruits of Citrus are popular all over the world. It was reported that the extracts of fruits possessed antiallergic activities. In China, Citri Reticulatae Pericarpium (CRP) is a production of peels. In this study, flavonoids were extracted by solvent method, and enriched by polyamide. Then antiallergic activity of flavonoids was investigated in vivo and in vitro. Under optimal parameters, most abundant compounds of extracts were hesperidin and narirutin, their contents were 232.0325 and 98.7946 mg/g, respectively. In vitro, RBL-2H3 cell line was used to investigate the antiallergic activity. As the results shown, -hexosaminidase release of antigen-induced degranulation was decreased by flavonoids. An ovalbumin-induced allergic asthmatic model was used to test the activity of the flavonoids in vivo. After treated with different concentrations of flavonoids, the levels of IgE, IL-4, and IL-13 decreased significantly. These findings provide evidence that flavonoids extracted from CRP have potential using in antiallergic therapeutic area. Practical applicationsOranges are popular all over the world as fruit, besides a little percent of peels are applied as traditional medicine in China, the others are thrown away as rubbish. To explore the new way to extend the application of peels, we extracted the total flavonoids from Citri Reticulatae Pericarpium (CRP) and evaluated the antiallergic activity of it. Fortunately, the total flavonoids have antiallergic activity in vitro and vivo. The findings provide evidence that extracts from CRP have potential using in antiallergic therapeutic area. It can also afford a theoretical basis for the new application of orange peel.

关键词： Citrus fruits

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Design and Implementation of Electronic Image Stabilization System Based on Dual-core DSP

Design and Implementation of Electronic Image Stabilization ...

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9th International Conference on Intelligent Information Hiding and Multimedia Signal Processing (IIH-MSP)

作者： Zhang, Haolong Wu, Qiang liu, Tianqi li, xuwen Beijing Univ Technol Coll Elect Informat & Control Engn Beijing Peoples R China Beijing Univ Technol Coll Life Sci & Bioengn Beijing Peoples R China

ISBN: (纸本)9780769551203

Electronic image stabilization (EIS) technology is an important research area of video processing and computer vision. This paper presented a set of fast and parallel EIS algorithms. Firstly, this paper proposed a fast local motion vector (LMV) estimation algorithm based on the FAST feature to solve the problem that the traditional algorithm is too complex. Secondly, a parallel global motion vector (GMV) algorithm based on image division is designed, which computes every LMV simultaneously, and then estimates the GMV by all LMVs. Finally, based on the proposed algorithm, an EIS systems based on BF609 dual-core DSP processor is designed and implemented. Experiment results show that the algorithm and system presented in this thesis can effectively stabilize jittery video and achieve high real-time performance. When dealing with PAL standard video, the total time cost is less than 40ms.

关键词： electronic image stabilization parallel multi-core

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Studies on New Steroidal Saponins from Allii macrostemonis Bulbus and Their Antitumor Activities

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Chemical Research in Chinese Universities 2018年第1期34卷 61-66页

作者： YAO Hua WANG Tong WU Qian liU Ying li Peng li xuwen JIN Yongri Scienttfic Research Center China-Japan Union Hospital of Jilin University Changchun 130033 P. R. China College of Chemistry Jilin University Changchun 130012 P. R. China

Two new steroidal saponms（2, 3） and two known compounds（1, 4） were isolated from 75% ethanol extract ofAllii macrostemonis bulbus by various spectral methods. The two new steroidal saponins were respectively elucidated as （25S）-26-O-β-D-glucopyranosyl-5α-furostanol-2α,3β,22,26-tetrol-3-O-β-D-glucopyranosyl（1→2）-[β-D- glucopyranosyl（1→3）]-β-D-glucopyranosyl（1→4 ）-β-D-galactopyranoside（2 ） and 26-O-β-D-glucopyranosyl-5α- furostanol-25（ 27）-ene-3β,22,26-tetrol-3-O-β-D-glucopyranosyl（ 1→2 ）-[β-D-glucopyranosyl（ 1→3 ）] -β-D-glucopyranosyl- （1→4）-β-D-galactopyranoside（3）. Compound 4 was obtained from this medical plant for the first time. The activity experiments of proliferation inhibition on tumor cells were performed by cell counting kit-8（CCK-8） method for compound 2（25S-configuration） and its isomer（compound 1, 25R-configttration）. The results show that compounds 1 and 2 have weak inhibition on lung cancer A549 cells, melanoma A375 cells and breast cancer MCF-7 cells as well as certain inhibitory effect on liver cancer HepG2 cells, and the inhibitory effect of compound 1 is stronger than that of compound 2.

关键词： Allii macrostemonis bulbus Steroidal saponin Structure identification Proliferation inhibition Cell counting kit-8（CCK-8） method

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Research of The Real-time Performance of Operating System

Research of The Real-time Performance of Operating System

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5th International Conference on Wireless Communications, Networking and Mobile Computing

作者： Jun Shen Qiang Wu xuwen li Yanhua Zhang Beijing Univ Technol Coll Elect & Control Engn Beijing Peoples R China Beijing Univ Technol Coll Life Sci & Bio Engn Beijing Peoples R China

ISBN: (纸本)9781424436927

Contraposing the basic principles and mechanism of the real-time operating system, the paper has compared general operating systems with real-time operating system, and made a good effort to analyze the key factors which may affect the real-time characteristics of operating system, and then given a assessment methods to evaluate the real-time character of operating system. A practical application system is also tested at last.

关键词： real-time factor operating system

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