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A fast automatic recognition and location algorithm for fetal genital organs in ultrasound images

Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第9期10卷 648-658页

作者： Sheng tang Si-ping CHEN Post-Doctoral Research Station Shenzhen University Shenzhen 518060 China post-Doctoral WorkStation Microprofit Electronie Co. Ltd Shenzhen 518057 China Department of Biomedical Engineering Shenzhen University Shenzhen 518060 China

Severe sex ratio imbalance at birth is now becoming an important issue in several Asian countries. Its leading immediate cause is prenatal sex-selective abortion following illegal sex identification by ultrasound scanning. In this paper, a fast automatic recognition and location algorithm for fetal genital organs is proposed as an effective method to help prevent ultrasound technicians from unethically and illegally identifying the sex of the fetus. This automatic recognition algorithm can be divided into two stages. In the 'rough' stage, a few pixels in the image, which are likely to represent the genital organs, are automatically chosen as points of interest (POIs) according to certain salient characteristics of fetal genital organs. In the 'fine' stage, a specifically supervised learning framework, which fuses an effective feature data preprocessing mechanism into the multiple classifier architecture, is applied to every POI. The basic classifiers in the framework are selected from three widely used classifiers: radial basis function network, backpropagation network, and support vector machine. The classification results of all the POIs are then synthesized to determine whether the fetal genital organ is present in the image, and to locate the genital organ within the positive image. Experiments were designed and carried out based on an image dataset comprising 658 positive images (images with fetal genital organs) and 500 negative images (images without fetal genital organs). The experimental results showed true positive (TP) and true negative (TN) results from 80.5% (265 from 329) and 83.0% (415 from 500) of samples, respectively. The average computation time was 453 ms per image.

关键词： Ultrasound image Fetal genital organ Point of interest (POI) Feature selection Feature extraction Class imbalance Multiple classifier architecture

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Superior Energy and Power Density Realized in Pb(Hf_(1-x)Ti_(x))O_(3) System at Low Electric Field

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Energy Material Advances 2023年第1期4卷 185-196页

作者： Peng-Zu Ge Xin-Gui tang Qiu-Xiang Liu yan-ping Jiang Xiao-Bin Guo School of Physics and Optoelectric Engineering Guangdong University of TechnologyGuangzhou Higher Education Mega CenterGuangzhou 510006China

The development of antiferroelectric materials with large energy density and fast discharge speed makes dielectric capacitors possess great prospects for applications in pulsed power ***,the PbHfO_(3)-based ceramics with compositions of Pb(Hf_(1-x)Ti_(x))O_(3)(PHT,0.01≤x≤0.05)were synthesized,and their antiferroelectricity and phase transition behavior were *** to the tests of x-ray diffraction,dielectric spectrum,and polarization-electric field hysteresis loops,PHT ceramics gradually transition from an orthorhombic symmetric antiferroelectric phase to a hexagonal symmetric ferroelectric phase at room temperature as Ti^(4+)concentration *** forward phase switching field of antiferroelectric to ferroelectric phase transition can be markedly regulated by the introduction of Ti^(4+),and the optimal energy storage performance was obtained in Pb(Hf_(0.98)Ti_(0.02))O_(3) ceramics with a large recoverable energy storage density of Wrec~4.15 J/cm^(3) and efficiency ofη~65.3%only at a low electric field of 190 kV/***,the outstanding charge-discharge properties with an ultrafast discharge time(71 ns),remarkable discharged energy density(2.84 J/cm^(3)),impressive current density(1,190 A/cm^(2)),and ultrahigh power density(101 MW/cm^(3))at a low electric field of 170 kV/cm were obtained in studied *** excellent energy storage performance of PHT ceramics provides a promising platform for the application of dielectric capacitors.

关键词： ceramics ferroelectric dielectric

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Compositional metric learning for multi-label classification

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Frontiers of Computer Science 2021年第5期15卷 1-12页

作者： yan-ping SUN Min-Ling ZHANG School of Computer Science and Engineering Southeast UniversityNanjing 210096China Key Laboratory of Computer Network and Information Integration(Southeast University) Ministry of EducationChina Collaborative Innovation Center for Wireless Communications Technology Nanjing 211100China

Multi-label classification aims to assign a set of proper labels for each instance,where distance metric learning can help improve the generalization ability of instance-based multi-label classification *** multi-label metric learning techniques work by utilizing pairwise constraints to enforce that examples with similar label assignments should have close distance in the embedded feature *** this paper,a novel distance metric learning approach for multi-label classification is proposed by modeling structural interactions between instance space and label *** one hand,compositional distance metric is employed which adopts the representation of a weighted sum of rank-1 PSD matrices based on com-ponent *** the other hand,compositional weights are optimized by exploiting triplet similarity constraints derived from both instance and label *** to the compositional nature of employed distance metric,the resulting problem admits quadratic programming formulation with linear optimization complexity *** number of training *** also derive the generalization bound for the proposed approach based on algorithmic robustness analysis of the compositional *** experiments on sixteen benchmark data sets clearly validate the usefulness of compositional metric in yielding effective distance metric for multi-label classification.

关键词： machine learning multi-label learning metric learning compositional metric positive semidefinite matrix decomposition

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Mn evaporation and denitrification behaviors of molten Mn steel in the vacuum refining with slag process

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International Journal of Minerals,Metallurgy and Materials 2021年第8期28卷 1288-1297页

作者： Jian-hua Chu yan-ping Bao State Key Lab of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

Considering the precise composition control on the vacuum refining of high-Mn steel, the behaviors of both Mn evaporation and nitrogen removal from molten Mn steel were investigated via vacuum slag refining in a vacuum induction furnace. It was found that the reaction interfaces of denitrification and Mn evaporation tend to migrate from the surface of slag layer to the surface of molten steel with the gradual exposure of molten steel during the vacuum slag refining process. Significantly, compared with the experimental group without slag addition, the addition of slag into steel can result in a lower Mn evaporation rate constant of 0.0192 cm·min~(-1) at 370 Pa, while the denitrification rate is almost not affected. Besides, the slag has a stronger inhibitory effect on Mn evaporation than the reduced vacuum pressure. Moreover, the inhibitory effect of the slag layer on Mn evaporation can be weakened with the increase of the initial Mn content in molten steel. The slag layer can work as an inhibitory layer to reduce the Mn evaporation from molten steel, the evaporation reaction of Mn mainly proceeds on the surface of the molten steel. This may be attributed to the Mn mass transfer coefficient for one of reaction at steel/slag interface, mass transfer in molten slag, and evaporation reaction at slag/gas interface is lower than that of evaporation reaction at steel/gas interface. The introduction of slag is proposed for both denitrification and manganese control during the vacuum refining process of Mn steels.

关键词： manganese evaporation denitrification vacuum slag evaporation rate

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基于固定化金属亲和整体柱的痕量微囊藻毒素富集分析

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分析测试学报 2025年第1期44卷 155-162,171页

作者：陈小燕杨玲苏立燊吴晓苹福州大学化学学院食品安全与生物分析教育部重点实验室福建福州350116 泉州市晋江环境监测站福建泉州362200 福建省妇幼保健院福建福州350001

基于固定化金属亲和色谱(IMAC)识别原理,采用后修饰法在热引发自由基聚合反应得到的有机基质整体柱上直接固定Cu^(2+),设计并合成表征了poly(VIM-co-DVB)-Cu^(2+)亲和毛细管整体柱,用于微囊藻毒素(MCs)的富集研究。详细优化了亲和整体... 详细信息

基于固定化金属亲和色谱(IMAC)识别原理,采用后修饰法在热引发自由基聚合反应得到的有机基质整体柱上直接固定Cu^(2+),设计并合成表征了poly(VIM-co-DVB)-Cu^(2+)亲和毛细管整体柱,用于微囊藻毒素(MCs)的富集研究。详细优化了亲和整体柱的萃取条件,在最优条件下,将poly(VIM-co-DVB)-Cu^(2+)整体柱用于毛细管微萃取(CME),并与高效液相色谱-质谱(HPLC-MS)检测技术联用,建立了环境水样品中3种MCs的高效富集分析方法。方法检出限为0.89~1.23 ng/L,加标回收率为80.0%~105%,相对标准偏差(RSD)不大于6.8%。该方法灵敏度高、准确性好,可为污染水体中微囊藻毒素的监测分析提供有效手段。

关键词：微囊藻毒素固定化金属亲和整体柱毛细管微萃取高效液相色谱-质谱

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A new flavonoid glucoside from Cassia angustifolia

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Chinese Chemical Letters 2009年第3期20卷 320-321页

作者： Qiu ping Wu Zhu Ju Wang Li Ying tang Mei Hong Fu yan He Institute of Traditional Chinese Materia Medica China Academy of Chinese Medical Sciences Beijing 100700 China The National Pharmaceutical Engineering Center (NPEC) for Solid Preparation in Chinese Herbal Medicine Nanchang 330006 China

A new flavonoid glucoside with a known one was isolated from the leaves of Cassia angustifolia. Based on the spectral analysis, including MS, ^1H NMR, ^13C NMR, DEPT, ^1H-1HCOSY, HMQC, HMBC and NOSEY, their chemical structures were determined as kaempferol-3-O-[（6＇＇＇-O-trans-sinnapoyt）-β-D-glucopyranosyl （1 → 6）]-β-D-glucopyranoside 1 and apigenin-6,8-di-C-glycoside 2.

关键词： Cassia angustifolia Flavonol glucoside Kaempferol-3-O-[ (6'''-O-trans-sinnapoyl)-β-D-glucopyranosyl-(1→6)]-β-D-glucopyranoside

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Influence of Tb on easy magnetization direction and magnetostriction of PrFe1.9 alloy

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Chinese Physics B 2019年第11期28卷 333-338页

作者： Chang-Xuan He yan-Mei tang Xiang Li Yun He Cai-yan Lu Ze-ping Guo College of Physics and Technology Guangxi Normal UniversityGuilin 541004China School of Electronic Engineering and Automation Guilin University of Electronic TechnologyGuilin 541004China

The crystal structures, magnetization, and spontaneous magnetostriction of ferromagnetic Laves phase Pr1-xTbxFe1.9 compounds are investigated in a temperature range between 5 K and 300 K. High resolution synchrotron x-ray diffraction(XRD) analysis shows that different proportions of Tb in Pr1-xTbxFe1.9 alloys can result in different easy magnetization directions(EMD) below 70 K, i.e., [100] with x = 0.0, and [111] with x ≥ 0.1. This indicates Tb substitution can lead the EMD to change from [100] to [111] with x rising from 0.0 up to 0.1. The Tb substitution for Pr reduces the saturation magnetization Ms and the magnetostriction to their minimum value when x = 0.6, but it can increase low-field(0 ≤ H ≤9 kOe, the unit 1 Oe = 79.5775 A·m-1) magnetostriction when x = 0.8 and 1.0 at 5 K. This can be attributed to the larger magnetostriction of PrFe1.9 than that of TbFe1.9, as well as the decrease of the resulting anisotropy due to Tb substitution at low temperatures.

关键词： Tb substitution spin reorientation magnetostriction easy magnetization direction(EMD)

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Antioxidant Activity of Pigment Extracted from Green-Wheat-Bran

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Agricultural Sciences in China 2010年第6期9卷 825-832页

作者： tang Xiao-zhen DONG Yu-xiu WEI Si-qing ZHANG Xian-sheng YIN yan-ping Shandong Agricultural University Tai＇an 271018 P.R.China Shandong External Economy Trade Technical School Tai＇an 271000 P.R.China

The anthocyanin pigment extracted from green-wheat-bran was studied to identify its antioxidant *** antioxidant activities of the pigment were evaluated by anti-lipid peroxidation,total antioxidant activity （TAA）,superoxide anion radical scavenging activity （SARSA）,active oxygen scavenging activity （AOSA）,and DPPH （1,1-diphenyl-2 picrylhydrazyl free radical） radical scavenging *** results showed that the pigment had higher antioxidant activity and TAA,SARSA,AOSA and *** activities at a certain concentration than Vc （antiscorbutic vitamin,vitamin C）,and the capacity increased with the increase of pigment *** TAA was 51.06 U mL-1,1.73 times of Vc,and SARSA 18 025.21 U mL-1,2.26% higher than Vc,and AOSA 3 776.31 U mL-1,1.24 times of *** to the *** activity of the pigment,there was a trend that higher concentration performed higher activity significantly improved with the company of *** pigment showed significant antioxidant activities evaluated by different *** will provide a better understanding on antioxidant activity of green wheat and allow the screening or breeding of green wheat varieties with higher antioxidant activity for food processing.

关键词： pigment from green-wheat-bran anti-lipid peroxidation total antioxidant superoxide anion radical scavenging,active oxygen scavenging DPPH.scavenging

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Effects of Dietary Protein Variations at Different Life-stages on Vocal Dominance of the African Clawed Frogs

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Asian Herpetological Research 2020年第3期11卷 249-256页

作者： yan CAO Jiangyan SHEN Xiaocui WANG Song TAN ping LI Jianghong RAN Yezhong tang Jingfeng CHEN Thematic Area of Biodiversity and Ecosystem Services Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041SichuanChina Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education College of Life SciencesSichuan UniversityChengdu 610041SichuanChina University of the Chinese Academy of Sciences Beijing 100049China

How nutritional conditions during early development affect an organism’s phenotype at adulthood is still poorly understood despite a plethora of research on developmental ***"environmental matching"hypothesis predicts that individuals will have high fitness providing that their adult environment"matches"what they experienced during *** contrast,the"silver spoon"hypothesis predicts that individuals who obtain better developmental resources will be generally *** we tested these two hypotheses and examined the underlying hormonal mechanisms by manipulating the early dietary protein content of African clawed frogs(Xenopus laevis)for a year with a 2×2 factorial experimental *** found that only a lowprotein food during development enhanced the vocal competition ability of male ***,and that vocal dominance was associated with higher cortisol levels but not related with testosterone *** results were not congruent with the"environmental matching"hypothesis or with the"silver spoon"hypothesis,suggesting the behavioral plasticity during development is more complex than our expectation in amphibians.

关键词： aggression developmental effects environmentalmatching silver spoon social status vocal competition Xenopus laevis

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Evaluation of Burden Descent Model for Burden Distribution in Blast Furnace

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Journal of Iron and Steel Research International 2016年第8期23卷 765-771页

作者： ping ZHOU Peng-yu SHI yan-po SONG Kai-le tang Dong FU Chenn Q.ZHOU School of Energy Science and Engineering Central South University Center for Innovation through Visualization and Simulation Purdue University Calumet

Mathematical models for burden descending process have been applied to obtain whole burden structures in blast furnace,whereas the accuracy of those burden descent models has not been sufficiently *** evaluation method based on timeline burden profiles was established to quantitatively evaluate the error between experimental and modeled burden *** existing burden descent models were utilized to describe the burden structure of a 1/20 scaled warm blast *** modeling conditions including initial burden profile,descending volumes in each time interval,and normalized descending velocity distribution were determined via special image processing *** burden structures were evaluated combined with the published experimental *** is found that all the models caught the main profile of the burden ***,the improved nonuniform descent model（Model IV）shows the highest level of precision especially when burden descends with unstable velocity distribution ***,the traditional nonuniform descent model（Model III）may also be desirable to model the burden descending process when the burden descending velocity presents a linear ***,the uniform descent model（Model I）might be the first option for roughly predicting burden structure.

关键词： burden descending descent normalized utilized scaled sufficiently modeled desirable quantitatively

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