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Deep learning applied to two-dimensional color Doppler flow imaging ultrasound images significantly improves diagnostic performance in the classification of breast masses:a multicenter study

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Chinese Medical Journal 2021年第4期134卷 415-424页

作者： Teng-Fei Yu Wen He Cong-Gui Gan Ming-Chang Zhao Qiang Zhu Wei Zhang Hui Wang Yu-Kun Luo Fang Nie Li-Jun Yuan Yong Wang Yan-Li Guo Jian-Jun Yuan Li-Tao Ruan Yi-Cheng Wang Rui-Fang Zhang Hong-Xia Zhang Bin Ning hai-man song Shuai Zheng Yi Li Yang Guang Department of Ultrasound Beijing Tian Tan HospitalCapital Medical UniversityBeijing 100070China Department of R&D CHISON Medical Technologies Co.LtdWuxiJiangsu 214028China Department of Ultrasound Beijing Tongren HospitalCapital Medical UniversityBeijing 100730China Department of Ultrasound The Third Affiliated Hospital of Guangxi Medical UniversityNanningGuangxi 9530031China Department of Ultrasound China-Japan Union Hospital of Jilin UniversityChangchunJilin 130033China Department of Ultrasound Chinese PLA General HospitalBeijing 100850China Department of Ultrasound Lanzhou University Second HospitalLanzhouGansu 730030China Department of Ultrasound Xi'an Tangdu Hospital of No.4 Military Medical UniversityXi'anShaanxi 710038China Department of Ultrasound Chinese Academy of Medical Sciences Cancer Institute and HospitalBeijing 100021China Department of Ultrasound The Third M ilitary Medical University Southwest HospitalChongqing 400038China Department of Ultrasound Henan Provincial People's HospitalZhengzhou cityHenan 450003China Department of Ultrasound Xi'an Jiaotong University Medical College First Affiliated HospitalXi'anShaanxi 710061China Department of Ultrasound Hebei Medical University First Affiliated HospitalZhangjiakouHebei 075061China Department of Ultrasound Zhengzhou University First Affiliated HospitalZhengzhouHenan 450052China.

Background:The current deep learning diagnosis of breast masses is mainly reflected by the diagnosis of benign and malignant *** China,breast masses are divided into four categories according to the treatment method:inflammatory masses,adenosis,benign tumors,and malignant *** categorizations are important for guiding clinical *** this study,we aimed to develop a convolutional neural network(CNN)for classification of these four breast mass types using ultrasound(US)***:Taking breast biopsy or pathological examinations as the reference standard,CNNs were used to establish models for the four-way classification of 3623 breast cancer patients from 13 *** patients were randomly divided into training and test groups(n=1810 vs.n=1813).Separate models were created for two-dimensional(2D)images only,2D and color Doppler flow imaging(2D-CDFI),and 2D-CDFI and pulsed wave Doppler(2D-CDFI-PW)*** performance of these three models was compared using sensitivity,specificity,area under receiver operating characteristic curve(AUC),positive(PPV)and negative predictive values(NPV),positive(LR+)and negative likelihood ratios(LR-),and the performance of the 2D model was further compared between masses of different sizes with above statistical indicators,between images from different hospitals with AUC,and with the performance of 37 ***:The accuracies of the 2D,2D-CDFI,and 2D-CDFI-PW models on the test set were 87.9%,89.2%,and 88.7%,*** AUCs for classification of benign tumors,malignant tumors,inflammatory masses,and adenosis were 0.90,0.91,0.90,and 0.89,respectively(95%confidence intervals[CIs],0.87-0.91,0.89-0.92,0.87-0.91,and 0.86-0.90).The 2D-CDFI model showed better accuracy(89.2%)on the test set than the 2D(87.9%)and 2D-CDFI-PW(88.7%)*** 2D model showed accuracy of 81.7%on breast masses≤1 cm and 82.3%on breast masses>1 cm;there was a significant difference between the two groups(P<0.001).The accu

关键词： Deep learning Ultrasonography Breast diseases Diagnosis

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Fundamental mechanism of effects of MgO on sinter strength

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Journal of Iron and Steel Research International 2019年第11期26卷 1171-1177页

作者： Hong-song Han Feng-man Shen Xin Jiang Chuan-guang Bi hai-yan Zheng Qiang-jian Gao School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina Technology Center Meishan Iron and Steel Limited CorporationNanjing 210000JiangsuChina

MgO-containing flux may have a series of effects on the quality of sinter and performances of the blast ***,the fundamental mechanism of the effects of MgO on the sinter strength was *** the chemical reagent and industrial flux were used for preparing the *** experimental results show that the sinter strength decreases with MgO *** are three reasons for *** first reason is diffusion *** all of the CaO may react with Fe2O3 and generate CaO Fe2O3,but most of MgO cannot react with Fe2O3,and it still remains in the state of original *** diffusion rate of MgO in iron oxide is only 17.51μm/min in 30 *** second reason is the fluidity and ability to generate liquid *** the case of Fe2O3 mixed with CaO,there is some liquid phase formed above 1200℃,while in the case of Fe2O3 mixed with MgO,even at 1200 and 1220℃,there is still no liquid *** third reason is *** the case of industrial flux,the compression strength of the specimens made of Fe2O3 and limestone is 0.52 and 0.71 kN at 1150 and 1180℃,respectively,while that of the specimens made of Fe2O3 and magnesite is 0.48 and 0.56 kN,***,the fundamental mechanism of the effects of MgO additive on sinter strength can be better understood based on the diffusion rate of MgO in iron oxides,the fluidity of liquid phase,and the self-strength of bonding phase.

关键词： MgO addition Sinter strength Blast furnace Mineralization rate Fluidity Self-strength

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Effect of MgO on Oxidation Process of Fe_3O_4 in Pellets

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Journal of Iron and Steel Research International 2016年第10期23卷 1007-1011页

作者： Qiang-jian GAO Yan-song SHEN Xin JIANG hai-yan ZHENG Feng-man SHEN Chang-sheng LIU School of Metallurgy Northeastern University School of Chemical Engineering University of New South Wales

Induration process of oxidized pellets involves the oxidation of Fe3O4 and re-crystallization of *** oxidation process of Fe3O4 is significant for pellets to obtain better ambient ***,the effect of MgO on oxidation process of Fe3O4 was *** unreacted core model was applied to analyze the oxidizing induration process of *** experimental results show that MgO plays a negative role in the oxidation process of *** oxidation rate of Fe3O4 in MgO-fluxed pellets（95.0% Fe3O4 ＋5.0% MgO）is slower than that in standard acid pellets（100% Fe3O4）.The relation between oxidation ratio of Fe3O4 and time was calculated based on the unreacted core model for both MgO-fluxed pellets and standard acid *** to verification experiments,the values calculated by model coincide well with the experimental ***,the unreacted core model could be applied to describe the oxidizing induration process of pellets.

关键词： MgO-fluxed pellet Fe3O4 oxidation unreacted core model

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Identifying the limiting distribution by a general approach of Stein's method

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Science China Mathematics 2016年第12期59卷 2379-2392页

作者： SHAO Qi-man ZHANG Zhuo-song Department of Statistics The Chinese University of Hong Kong

A general exchange pair approach is developed to identify the limiting distribution for any sequence of random variables, by calculating the conditional mean and the conditional second moments. The error of approximation is also studied. In particular, a Berry-Esseen type bound of O(n^(-3/4)) is obtained for the Curie-Weiss model at the critical temperature.

关键词： Stein's method exchangeable pair limiting distribution Berry-Esseen bounds Curie-Weiss model

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Effect of operational and geometric parameters on the hydrodynamics of a Wurster coater:A CFD-DEM study

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Particuology 2024年第2期85卷 62-76页

作者： Yinqiang song Tuo Zhou Ruiqi Bai man Zhang hairui Yang Department of Energy and Power Engineering Tsinghua UniversityBeijing100084China Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Tsinghua UniversityBeijing100084China State Key Laboratory of Power System and Generation Equipment Tsinghua UniversityBeijing100084China

A coupled CFD-DEM method was used to study the hydrodynamics of a Wurster ***,the CFD part of the model was validated by the accurate prediction of the pressure drops over a pseudo-2D fluidized bed under various gas *** effect of gas velocity,gap height,tube length and batch volume of the particles on the cycle time and the residence time of the particles was thoroughly *** central jet gas velocity ui was found to speed up the particle cycle but undermine the coating *** gas velocity at the horizontal transport zone u2 was able to promote the horizontal transport of the particles but should not be too high,otherwise,it would obstruct the normal falling back of the particles in the downward *** gap heights would decrease the coating efficiency but tube length had little impact on *** increment of batch volume would commonly abase the cycle time and the working efficiency under a given *** de-fluidization problem arose when the batch volume increased to 550 ***,this problem could be swept out by the optimization of u1 and *** a mixture of different sizes,the coarse particles enjoyed higher coating efficiency and could travel closer to the *** may shield the fine particles from getting enough coating liquids,and thus coarse particles and fine particles were not recommended to get coated in the same batch.

关键词： Numerical simulation CFD-DEM Wurster coater Hydrodynamics Cycle time Residence time

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Variation of soil fertility and carbon sequestration by planting Hevea brasiliensis in hainan Island, China

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Journal of Environmental Sciences 2007年第3期19卷 348-352页

作者： CHENG Chun-man WANG Ru-song JIANG Ju-sheng Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Research and Development Center of hainan State Farm Bureau Haikou 570212 China

The development of rubber industry depends on the sustainable management of rubber plantation. To evaluate the environmental effects of planting Hevea brasiliensis on a subsystem of tropical forest ecosystem, the variation of soil fertility and carbon sequestration under rubber plantation within 30-year life period were investigated in hainan Island. Results showed that （1） with the increase of stand age of rubber plantation, soil fertility decreased all along. From 1954 to 1995, soil organic matter, total N, available K and available P decreased by 48.2%, 54.1%, 56.7% and 64.1%, respectively. （2） If the complete return of litters was considered without additional fertilizer application to the soil of the rubber plantations, the consumption periods for P, N, K, Mg were only 825 years, 329 years, 94 years and 65 years, respectively~ To improve soil fertility is essential for rubber plantation development. （3） The C sequestration of rubber trees per hectare accounts for 272.08 t within 30-year life period and 57.91% of them was fixed in litters. In comparison with C sequestration by rain forest （234.305 t/hm^2） and by secondary rain forest （150.203 t/hm^2）, rubber forest has more potentials for C fixation. On the base of above results, the following measures would benefit the maintenance of soil fertility and the development of rubber industry, including applying fertilizer to maintain the balance of soil nutrients, intercropping leguminous plant to improve soil fertility, reducing the collection of litters, optimizing soil properties to improve element P availability such as applying CaCO3. The information gathered from the study can be used as baseline data for the sustainable management of rubber plantation elsewhere.

关键词： soil fertility carbon sequestration rubber plantation hainan Island

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Polyoxometalate-based high-nuclear cobalt-vanadium-oxo cluster as efficient catalyst for visible light-driven CO2 reduction

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Chinese Chemical Letters 2019年第6期30卷 1273-1276页

作者： Lizhen Qiao man song Aifang Geng Shuang Yao School of Chemical and Environmental Engineering Changchun University of Science and Technology Changchun 130022 China School of Chemistry and Chemical Engineering Tianjin University of Technology Tianjin 300384 China

A high-nuclear Co-V-O cluster was firstly isolated by lacunary polyoxoanion, resulting in the high-nuclear mixed metal-oxo cluster-containing polyoxometalate (POM), K4Na28[{Co4(O-H)3(VO4)}4(SiW9O34)4]· 66H2O (1). In 1, the{Co4(O-H)3(VO4)}4{Co16-V4}core, composed of a{Co4O4}cubane, four{Co4(OH)3}qusi-cubanes and four VO4 units, was stabilized by four lacunary A-α-{SiW9O34} units. Photocatalytic study reveals that 1 exhibits excellent photocatalytic activity for CO2-to-CO conversion with high selectivity under visible light irradiation. The turnover number (TON) and turnover frequency (TOF) reaches as high as 10492 and 0.29 s^-1, respectively. Compound 1 represents the first high nuclear TM cluster-containing POM (TM=transition-metal) with efficient visible light catalytic activity for CO2 reduction, and its photocatalytic activity is much higher than those of most reported molecular catalysts. Photoluminescence spectroscopy study reveals that photoexcitation of Ru-photosensitizer is followed by an efficient electron transfer to POMs to reduce CO2.

关键词： Polyoxometalate High-nuclear cobalt cluster Photocatalysis CO2 reduction Photosensitizer

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Computational I(Ⅲ)-X BDEs for Benziodoxol(on)e-based Hypervalent Iodine Reagents:Implications for Their Functional Group Transfer Abilities

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Chinese Journal of Chemistry 2019年第4期37卷 359-363页

作者： Jin-Dong Yang man Li Xiao-song Xue Center of Basic Molecular Science Department of ChemistryTsinghua UniversityBeijing 100084China State Key Laboratory of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin 300071China

The first comprehensive I(Ⅲ)-X(X=F,Br,CN,N3,CF3,etc.)bond dissociation energy(BDE)scales for benziodoxol(on)e-based hypervalent iodine reagents have been developed by virtue of DFT *** correlation is observed between the I(Ⅲ)-X BDEs and the X-H BDEs,offering a powerful avenue to quickly estimate the group-transfer ability of a novel benziodoxol(on)e-based hypervalent reagent.

关键词： avenue CF3 DFT

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Cache-Enabled in Cooperative Cognitive Radio Networks for Transmission Performance

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Tsinghua Science and Technology 2020年第1期25卷 1-11页

作者： Jiachen Yang Chaofan Ma Jiabao man Huifang Xu Gan Zheng Houbing song School of Electrical and Information Engineering Tianjin UniversityTianjin 300000China Wolfson School of Mechanical Electrical and Manufacturing EngineeringLoughborough UniversityLoughboroughLE11 3TUUK Department of Electrical ComputerSoftwareand Systems EngineeringEmbry-Riddle Aeronautical UniversityDaytona BeachFL 32114USA.

The proliferation of mobile devices that support the acceleration of data services(especially smartphones)has resulted in a dramatic increase in mobile traffic. Mobile data also increased exponentially, already exceeding the throughput of the backhaul. To improve spectrum utilization and increase mobile network traffic, in combination with content caching, we study the cooperation between primary and secondary networks via content caching. We consider that the secondary base station assists the primary user by pre-caching some popular primary ***, the secondary base station can obtain more licensed bandwidth to serve its own user. We mainly focus on the time delay from the backhaul link to the secondary base station. First, in terms of the content caching and the transmission strategies, we provide a cooperation scheme to maximize the secondary user’s effective data transmission rates under the constraint of the primary users target rate. Then, we investigate the impact of the caching allocation and prove that the formulated problem is a concave problem with regard to the caching capacity allocation for any given power allocation. Furthermore, we obtain the joint caching and power allocation by an effective bisection search algorithm. Finally, our results show that the content caching cooperation scheme can achieve significant performance gain for the primary and secondary systems over the traditional two-hop relay cooperation without caching.

关键词： cooperative cognitive radio network content caching power allocation

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Investigation of combined degrader for proton facility based on BDSIM/FLUKA Monte Carlo methods

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Nuclear Science and Techniques 2022年第2期33卷 30-39页

作者： man-Fen Han Jin-Xing Zheng Xian-Hu Zeng Jun-song Shen Hefei Institutes of Physical Science Chinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China

The significant advantage of proton therapy over other particle-based techniques is in the unique physical characteristics of the Bragg *** can achieve a highly conformal dose distribution and maximize the probability of tumor control by varying the irradiation *** proton facilities use cyclotrons for fixed energy beam extraction and are equipped with degrader and collimator systems for energy modulation and emittance ***,interactions between charged particles and degrader materials inevitably cause beam loss and divergence and deteriorate beam performance,which present great challenges for downstream transport and clinical *** this work,we investigate a method of energy reduction by combining boron carbide and graphite in a degrader to obtain greater beam transmission at lower *** results demonstrate that the beam size and emittance at the exit of the combined degrader diverge less than those of multi-wedge one in the energy range of 70-160 ***,the transmission efficiency after the first dipole also shows improvements of 36.26%at 70 MeV and 70.55%at 110 *** a component with a high activity level,the degrader causes additional ambient radiation during *** induced radiation even remains several hours after system *** of material activation and induced radiation based on 1 h irradiation with a 400 nA beam current shows that the combined degrader has a definite advantage in shielding despite producing more secondary *** radioactivity and average ambient dose equivalent are reduced by 50%compared with the multiwedge degrader at the important cooling time of 1 *** 12 h and 24 h of cooling,the radiation levels of degraders decrease slightly due to the presence of long half-life residual *** average dose generated from the multi-wedge degrader is still 1.25 times higher than that of the combined one.

关键词： Proton therapy Degrader Boron carbide Transmission efficiency Radionuclide Ambient dose equivalent

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