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Medical Image Compression by Applying 3D DWT in PACS

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Wuhan University Journal of Natural Sciences 1999年第3期4卷 313-318页

作者： Wang Si-xian li fei-peng Zeng Fa-long liao Meng-yang li Hui Wuhan Univ Wuhan China

The process of image compression in a practical Picture Archiving and Communication System (PACS) was discussed with detail. To fully reduce the inter-slice correlation existing in the volumetric image sets generated by CT and MR, 3D Discrete Wavelet Transformation (DWT) was introduced in our application. Instead of using a fixed quantizer of lossless low frequency and distinct loss of high frequency, an adaptive quantizer was devised taking MSE as the performance index. In the low frequency subband, DPCM was replaced withS+P transform to facilitate coding computation. Compared with JPEG or 2D DWT, our method is 20%–50% more efficient. Furthermore, preliminary tests showed that 33 dB may be the maximal distortion threshold for CT images.

关键词： PACS 3D DWT S+P transformation optimal bit allocation maximal distortion threshold

Three-Center Experience on Patients with Influenza-Associated Acute Respiratory Distress Syndrome in Chongqing, China

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Chinese Medical Journal 2018年第10期131卷 1244-1245页

作者： Xue-fei Yang Tomer Talmy peng-fei li Yao-Rong Zhang Wei-Jun Song Yao-li Wang Jian Zhou Intensive Care Unit Trauma Center The Daping Hospital and Research Institute of Surgery of Army Medical University Chongqing 400042 China Hadassah Medical Center The Institute of Research in Military Medicine The Hebrew University of Jerusalem Jerusalem 91120 Israel Intensive Care Unit Changan Hospital Chongqing 400021 China Intensive Care Unit Wushan County People's Hospital of Chongqing Chongqing 404700 China

To the Editor：Influenza-associated acute respiratory distress syndrome （ARDS） remains a devastating clinical picture. From December 2017 to January 2018,ten patients with influenza-associated ARDS were admitted to three different hospital＇s Intensive Care Units （ICUs） in Chongqing,with all cases resulting in *** main documented reasons for their admission to the ICU were due to progressive dyspnea and worsening hypoxemia which lead to endotracheal intubation and mechanical ventilation in these *** of influenza viruses was achieved using nucleic-acid testing from venous *** study was approved by the Institutional Review Board of Daping Hospital,Army Medical University.

关键词： A H1N1 ARDS

On the Factors Influencing the High Stretch-Flangeability of a Low-Density 1180 MPa Fe-Mn-Al-C-Nbδ-QP Steel

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Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1291-1300页

作者： Dan‑Dan Cui peng Chen peng‑fei Wang Xiao‑Wu li Department of Materials Physics and Chemistry School of Materials Science and Engineeringand Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education)Northeastern UniversityShenyang 110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

Low-densityδ-quenching and partitioning(δ-QP)steels with excellent strength and ductility have been recently ***,there are still rare reports on the formability of δ-QP steels,which are critical for satisfying the manufacture of structural parts during the application in automotive *** the present work,an 1180 MPa Fe–Mn–Al–C–Nbδ-QP steel with a high ductility was adopted for the stretch–flangeability ***δ-QP steel was developed by separated quenching and partitioning processes.A good hole expansion ratio(HER)of 34.9±0.9%was obtained in the quenched steel,but it has been further increased to 52.2%by the tempering *** improved stretch–flangeability was attributed to the enhanced austenite stability and deformation *** the one hand,the stability of austenite was increased by carbon partitioning during tempering,which reduced crack possibility via the suppression of the fresh martensite *** the other hand,the tempering treatment released the internal stress caused by martensitic transformation and reduced the difference in strength among different phases,resulting in an increase in the resistance to crack initiation and propagation.

关键词： Hole expansion ratio Low-densityδ-quenching and partitioning(δ-QP)steel Stretch-flangeability Austenite stability Deformation uniformity

Fate of fertilizer nitrogen and residual nitrogen in paddy soil in Northeast China

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Journal of Integrative Agriculture 2023年第11期22卷 3535-3548页

作者： BI Shi-ting LUO Xiang-yu ZHANG Chen li peng-fei YU Cai-lian liU Zhi-lei peng Xian-long College of Agricultural Resources and Environmental Sciences Northeast Agricultural UniversityHarbin 150030P.R.China Key Laboratory of Germplasm Enhancement Physiology and Ecology of Food Crops in Cold Region of Ministry of EducationNortheast Agricultural UniversityHarbin 150030P.R.China The School of Material Science and Chemical Engineering Harbin University of Science and TechnologyHarbin 150080P.R.China

The relationship between the fate of nitrogen (N) fertilizer and the N application rate in paddy fields in Northeast China is unclear,as is the fate of residual *** clarify these issues,paddy field and15N microplot experiments were carried out in 2017 and 2018,with N applications at five levels:0,75,105,135 and 165 kg N ha–1(N0,N75,N105,N135 and N165,respectively).15N-labeled urea was applied to the microplots in 2017,and the same amount of unlabeled urea was applied in *** (NH3) volatilization,leaching,surface runoff,rice yield,the N contents and15N abundances of both plants and soil were *** results indicated a linear platform model for rice yield and the application rate of N fertilizer,and the optimal rate was 135 kg N ha–1.N uptake increased with an increasing N rate,and the recovery efficiency of applied N (REN) values of the difference subtraction method were 45.23 and 56.98%on average in 2017and 2018,*** RENwas the highest at the N rate of 135 kg ha–1in 2017 and it was insignificantly affected by the N application rate in 2018,while the agronomic efficiency of applied N (AEN) and physiological efficiency of applied N (PEN) decreased significantly when excessive N was applied.N loss through NH3volatilization,leaching and surface runoff was low in the paddy fields in Northeast ***3volatilization accounted for 0.81 and 2.99%of the total N application in 2017 and 2018,*** average,the leaching and surface runoff rates were 4.45% and less than 1.05%,respectively,but the apparent denitrification loss was approximately 42.63%.The residual N fertilizer in the soil layer (0–40 cm) was 18.37–31.81 kg N ha–1in 2017,and the residual rate was 19.28–24.50%.Residual15N from fertilizer in the soil increased significantly with increasing N fertilizer,which was mainly concentrated in the 0–10 cm soil layer,accounting for 58.45–83.54% of the total residual N,and decreased with increasing *** the ratio of residual N in the

关键词： fate of N fertilizer NH_(3) volatilization leaching surface runoff residual nitrogen yield

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合成氨副产蒸汽综合利用技术

纯碱工业 2024年第5期 45-48页

作者：李鹏飞王海平李栓林张祖红库流金重庆湘渝盐化有限责任公司重庆万州404000

蒸汽作为能源及热源载体,在合成氨生产中起到举足轻重的作用,通过热量回收副产蒸汽综合利用亦是相关企业节能重要举措之一。通过对重庆湘渝盐化公司新老合成氨装置工艺流程中副产蒸汽的产生途径、工艺参数、回收和利用途径进行对比,研... 详细信息

蒸汽作为能源及热源载体,在合成氨生产中起到举足轻重的作用,通过热量回收副产蒸汽综合利用亦是相关企业节能重要举措之一。通过对重庆湘渝盐化公司新老合成氨装置工艺流程中副产蒸汽的产生途径、工艺参数、回收和利用途径进行对比,研究煤气化节能升级改造新合成装置副产蒸汽回收利用技术。

关键词：合成氨蒸汽回收综合利用废热锅炉蒸汽等级

Existence of Positive Solutions to a Fractional-Kirchhoff System

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 225-240页

作者： peng-fei li Jun-hui Xie Dan Mu School of Mathematics and Statistics Hubei Minzu UniversityEnshi445000China

LetΩbe a bounded smooth domain in RN(N≥3).Assuming that 00 are constants,we consider the existence results for positive solutions of a class of fractional elliptic system below,{(a+b[u]^(2)_(s))(-Δ)^(s)u=vp+h_(1)(x,u,v,▽u,▽v),x∈Ω,(-Δ)^(s)v=u^(q)+h_(2)(x,u,▽,▽u,▽v),x∈Q,u,v>0,x∈Ω,u=v=0,x∈RN\Ω.Under some assumptions of hi(x,u,v,▽u,▽v)(i=1,2),we get a priori bounds of the positive solutions to the problem(1.1)by the blow-up methods and rescaling *** on these estimates and degree theory,we establish the existence of positive solutions to problem(1.1).

关键词： fractional-Kirchhoff system a priori bounds degree theory positive solution

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应力吸收层沥青混合料压实特性研究

建材世界 2024年第2期45卷 63-68页

作者：李君述李鹏飞李想袁恒林振华磨炼同湖北楚天智能交通股份有限公司武汉430000 河南省豫南高速投资有限公司信阳465550 武汉理工大学硅酸盐建筑材料国家重点实验室武汉430070

为了解应力吸收层沥青混合料的压实特性,保证施工和易性,采用旋转压实仪成型试件,利用压实度与旋转次数的关系研究油石比、压实温度和矿料级配对压实特性的影响。结果表明:压实能量指数、压实速率、95%和99%压实度对应的压实次数均可作... 详细信息

为了解应力吸收层沥青混合料的压实特性,保证施工和易性,采用旋转压实仪成型试件,利用压实度与旋转次数的关系研究油石比、压实温度和矿料级配对压实特性的影响。结果表明:压实能量指数、压实速率、95%和99%压实度对应的压实次数均可作压实参数,压实速率对应力吸收层沥青混合料适用性不强,95%和99%压实度对应的合理压实次数为10次和35次,其可用于确定最佳油石比,提出了应力吸收层沥青混合料关键筛孔1.18 mm和2.36 mm合理通过率范围分别为45%~50%和65%~75%。

关键词：应力吸收层旋转压实压实特性压实温度级配控制

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成型方式对应力吸收层沥青混合料性能的影响

建材世界 2024年第1期45卷 61-64页

作者：石学文李鹏飞彭俊华李想林振华磨炼同湖北楚天智能交通股份有限公司武汉430000 河南省豫南高速投资有限公司信阳465550 武汉理工大学硅酸盐建筑材料国家重点实验室武汉430070

开展了旋转压实与马歇尔击实成型对应力吸收层沥青混合料体积和力学性能的影响分析。试验结果表明,应力吸收层配合比设计中可用马歇尔击实50次代替旋转压实50次成型试件,旋转压实试件与马歇尔试件的劈裂抗拉强度、贯入应力均具有良好相... 详细信息

开展了旋转压实与马歇尔击实成型对应力吸收层沥青混合料体积和力学性能的影响分析。试验结果表明,应力吸收层配合比设计中可用马歇尔击实50次代替旋转压实50次成型试件,旋转压实试件与马歇尔试件的劈裂抗拉强度、贯入应力均具有良好相关性,换算系数分别为1.347和0.910。提出了基于马歇尔击实方法的应力吸收层设计要求,可更好地进行配合比设计和工地现场质量控制。

关键词：应力吸收层旋转压实马歇尔击实贯入试验劈裂抗拉强度

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Fast charge transfer kinetics in Sv-ZnIn_(2)S_(4)/Sb_(2)S_(3)S-scheme heterojunction photocatalyst for enhanced photocatalytic hydrogen evolution

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Rare Metals 2024年第2期43卷 533-542页

作者： Wei li Jia-Jun li Zhi-fei liu Hong-Yu Ma peng-fei Fang Rui Xiong Jian-Hong Wei Key Laboratory of Artificial Micro-and Nano-Structures of Ministry of Education School of Physics and TechnologyWuhan UniversityWuhan430072China

Constructing a S-scheme heterojunction with tight interface contact and fast charge transfer is beneficial to improving the photocatalytic hydrogen evolution ***,a unique one-dimensional(1D)/two-dimensional(2D)S-scheme heterojunction containing 1D Sb_(2)S_(3) nanorods and 2D ZnIn_(2)S_(4) with affluent sulfur vacancies(denoted as Sv-ZnIn_(2)S_(4)@Sb_(2)S_(3)) was *** introduced sulfur vacancy can promote the effective adsorption of H+for the following interfacial hydrogen-evolution ***,the larger contact area and stronger electron interaction between Sb_(2)S_(3) and ZnIn_(2)S_(4) effectively inhibits the recombination of photo-generated electron–hole pairs and abridges the migration distance of *** a result,the optimal Sv-ZnIn_(2)S_(4)@Sb_(2)S_(3) sample achieves H_(2) evolution activity of 2741.3 mol·h^(−1)·g^(−1),which is 8.6 times that of pristine ZnIn_(2)S_(4) and 3.0 times that of the Sv-ZnIn_(2)S_(4) *** on the experimental result,the photo-reactivity S-scheme mechanism of hydrogen evolution from water splitting with Sv-ZnIn_(2)S_(4)@Sb_(2)S_(3) is *** work provides an effective method for developing S-scheme heterojunction composites of transition metal sulfide with high hydrogen evolution performance.

关键词： ZnIn_(2)S_(4) nanosheets S-scheme heterojunction Sulfur vacancy Charge transfer and separation Photocatalytic H_(2)evolution