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新型近似非齐次反向累加灰色模型研究及应用

洛阳师范学院学报 2024年第8期43卷 1-7页

作者：李长春陈友军马焕钦西华师范大学数学与信息学院四川南充637009

为提高灰色预测模型对不同特征序列的适应性,避免模型参数估计与参数应用的“非同源性”,实现模型优化与模型检验两个准则的一致性,基于背景值、建模机理、初始条件三个视角构建了一种新型近似非齐次反向累加灰色模型.研究表明,该模型... 详细信息

为提高灰色预测模型对不同特征序列的适应性,避免模型参数估计与参数应用的“非同源性”,实现模型优化与模型检验两个准则的一致性,基于背景值、建模机理、初始条件三个视角构建了一种新型近似非齐次反向累加灰色模型.研究表明,该模型对衰减序列、增长序列、齐次指数序列和非齐次指数序列都有较高的精度,是对现有灰色预测模型的有效补充.

关键词：灰色模型反向累加生成近似非齐次背景值初始条件

Bibliometric analysis and system review of vehicle routing optimization for emergency material distribution

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Journal of Traffic and Transportation Engineering(English Edition) 2022年第6期9卷 893-911页

作者： Jinxing Shen Kun Liu Changxi ma yongpeng Zhao Chuwei Shi College of Civil and Transportation Engineering Hohai UniversityNanjing 210098China School of Traffc and Transportation Lanzhou Jiaotong UniversityLanzhou 730070China

Determining the optimal vehicle routing of emergency material distribution(VREMD)is one of the core issues of emergency management,which is strategically important to improve the effectiveness of emergency response and thus reduce the negative impact of large-scale emergency *** summarize the latest research progress,we collected 511VREMD-related articles published from 2010 to the present from the Scopus database and conducted a bibliometric analysis using VOSviewer ***,we cautiously selected 49 articles from these publications for system review;sorted out the latest research progress in model construction and solution algorithms;and summarized the evolution trend of keywords,research gaps,and future *** results show that domestic scholars and research organizations held an unqualified advantage regarding the number of published ***,these organizations with the most publications performed poorly regarding the number of literature *** and the US have contributed the vast majority of the literature,and there are close collaborations between researchers from both *** optimization model of VREMD can be divided into single-,multi-,and joint-objective *** shortest travel time is the most common optimization objective in the single-objective optimization *** scholars focus on multiobjective optimization models to consider conflicting objectives *** recent literature,scholars have focused on the impact of uncertainty and special events(e.g.,COVID-19)on ***,some scholars focus on joint optimization models to optimize vehicle routes and central locations(or material allocation)*** algorithms can be divided into two primary categories,i.e.,mathematical planning methods and intelligent evolutionary *** branch and bound algorithm is the most dominant mathematical planning algorithm,while genetic algorithms and their enhancements are the most co

关键词： Transportation engineering Vehicle routing of emergency materials distribution Bibliometric analysis Optimization model Solution algorithms

基于RGB模型的脱绒棉种颜色特征与发芽状况的关系

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农业工程学报 2010年第10期26卷 172-177页

作者：张若宇坎杂马蓉曹卫彬李江波石河子大学机械电气工程学院石河子832000 浙江大学生物系统工程与食品科学学院杭州310029

为了得到脱绒棉种质量与其表面颜色特征之间的关系,采用数码相机拍照,利用图像处理技术提取脱绒棉种表面颜色特征,并严格按照GB/T3543.4-1995进行发芽试验,通过线性拟合和逐步回归分析,建立了脱绒棉种质量的颜色特征估算模型,并对其精... 详细信息

为了得到脱绒棉种质量与其表面颜色特征之间的关系,采用数码相机拍照,利用图像处理技术提取脱绒棉种表面颜色特征,并严格按照GB/T3543.4-1995进行发芽试验,通过线性拟合和逐步回归分析,建立了脱绒棉种质量的颜色特征估算模型,并对其精度进行了评价和验证。结果表明:基于R/(R+G+B)、G/(R+G+B)、(R-G-B)/(R+G)和R/G4个颜色特征参数,逐步回归模型决定系数R2分别为0.6949和0.7148,且均通过了P=0.01极显著性检验水平。该研究为基于RGB颜色模型对脱绒棉种实施快速、有效的分选提供了理论依据。

关键词：相关性颜色模型脱绒棉种发芽势发芽率

In situ growth process of Mg-Fe layered double hydroxide conversion film on MgCa alloy

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Journal of magnesium and Alloys 2021年第3期9卷 1019-1027页

作者： Jun Chen Ju Feng Lei yan Huan Li Changqi Xiong Sude ma Key Laboratory of Fluid and Power machinery of Ministry of Education School of Materials Science and EngineeringXihua UniversityChengdu 610039China

In this study,an environment-friendly layered double hydroxide(LDH)film has been deposited on Mg Ca alloy by a two-step *** improve the chemical conversion technique and control the film properties,batch studies have been carried out to address various process parameters such as pH value,treatment temperature and immersion *** chemical composition was determined by X-ray diffractometry and energy dispersive X-ray *** morphology was characterized by scanning electron *** corrosion resistance of the samples with various films was compared by polarization curves and immersion *** is found that the transformation duration of Mg-Fe LDH is *** high pH value and temperature has harmful effect on the purity of the film *** corrosion resistance of the films formed at low value of pH or high temperature or short treatment time is *** optimum process is as follows:the sample is first immersed in the solution containing Fe^(3+)/HCO_(3)^-/CO_(3)^(2-)with a pH value of 5 at a temperature of 55℃for 1 h to form a precursor film,and then this precursor film is immersed into the solution containing Fe^(3+)/HCO_(3)^-/CO_(3)^(2-)with a pH of 11 at 55℃for 24 h to obtain the Mg-Fe LDH conversion film.

关键词： magnesium alloy Layered double hydroxide Film Corrosion Parameter optimization

Actively implementing enteral nutrition to reduce parenteral nutrition-associated liver disease

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Hepatobiliary Surgery and Nutrition 2018年第5期7卷 409-411页

作者： Shuifang Jin Ronglin Jiang Weibin ma Intensive Care Unit First Affiliated HospitalZhejiang Chinese Medical UniversityHangzhou 310006China Department of Pha.ma.y First Affiliated HospitalZhejiang Chinese Medical UniversityHangzhou 310006China

For critically ill patients whose vital signs have been basically stable, especially those who have already suffered from malnutrition, the need to provide nutritional support has become the consensus of the medical c... 详细信息

关键词： parenteral patients Active

A quantitative study on changes of the myelinated fibers in the cerebral cortex of cortical dysplasia rats

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Neural Regeneration Research 2012年第4期7卷 268-272页

作者： Xuntai ma yong Tang yang Lv Oumei Cheng yong yan Department of Neurology Affiliated Hospital of Luzhou Medical College Luzhou 646000 Sichuan Province China Department of Histology and Embryology Institute of Basic Medical Sciences Chongqing Medical University Chongqing 400016 China Department of Neurology the First Affiliated Hospital of Chongqing Medical University Chongqing 400016 China Department of Geriatrics the First Affiliated Hospital of Chongqing Medical University Chongqing 400016 China

An animal model of cortical dysplasia was established through X-ray irradiation induced subcortical heterotopic nodules in rats. Transmission electron microscopy detection of the ultrastructure and the stereology examination showed that there was a significant decrease in cerebral white matter and hippocampal volume, the total volume, volume density, length density and total length of the myelinated fibers in the white matter of cortical dysplasia rats. Subcortical heterotopic nodules of the hippocampal CA1 region and synaptic number density in the CA3 region were reduced compared with normal rats. Our experimental findings indicate that erosed subcortical heterotopic nodules, decreased total length of myelinated nerve fibers and demyelination directly lead to a reduction of white matter volume.

关键词： cortical dysplasia heterotopic nodules white matter myelinated fibers medullary sheath stereology

The Influence of Trans-1,4-poly(butadiene-co-isoprene) Copolymer Rubbers(TBIR) with Different Molecular Weights on the NR/TBIR Blends

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Chinese Journal of Polymer Science 2019年第10期37卷 966-973,I0003页

作者： Hao Wang Ri-Guo Wang yun-Sheng ma Bo Luan Ai-Hua He Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization Key Laboratory of Rubber-plastics(Ministry of Education)School of Polymer Science and EngineeringQingdao University of Science and TechnologyQingdao 266042China Shandong Huaju Polymer material Co. Ltd.Binzhou 256500China

The molecular weight of a polymer is of prime importance and greatly influences the processing and mechanical properties of the polymer. Trans-1,4-poly(butadiene-co-isoprene) multi-block copolymer rubbers(TBIR) exhibit outstanding fatigue resistance, low heat build-up and good abrasion resistance, and are expected to be desirable candidate for high performance tire. Study on the influence of TBIR with different molecular weights on the structure and properties of TBIR and natural rubber(NR)/TBIR blends is essential to understand its contribution to the greatly improved dynamic properties of the rubber vulcanizates. TBIR with different molecular weights characterized by 1H-NMR, 13C-NMR, GPC, and DSC were highly trans-1,4-copolymers with similar chain sequence distribution and crystalline trans-1,4-polyisoprene(TPI) blocks. The green strength and modulus of TBIR increased with the increasing molecular *** NR/TBIR compounds filled with 40 phr carbon black were chemically cured by sulfur for the preparation of NR/TBIR *** compatibility between NR and TBIR, filler distribution, crosslinking bond and density, and properties of NR/TBIR vulcanizates were studied. The NR/TBIR vulcanizates showed increasing tensile strength, hardness, modulus, rebound, abrasion resistance, and flexural fatigue properties with increasing molecular weight of TBIR. Furthermore, they presented significant improvement in flexural fatigue resistance when compared with that of NR vulcanizate. The contribution mechanism of TBIR on the NR/TBIR blends was discussed. The TBIR with a wide range of molecular weight are ideal rubbers for high performance tires.

关键词： Trans-1,4-poly(butadiene-co-isoprene)copolymer rubber Nature rubber Blends Molecular weight Fatigue resistance

中药联合优思明治疗非超重型多囊卵巢综合征阴虚血燥证疗效观察

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浙江中西医结合杂志 2024年第10期34卷 939-943页

作者：沈明霞叶晨书马倩雯杭州市第九人民医院中医科杭州311225

多囊卵巢综合征(polycystic ovary syndrome,PCOS)是临床常见的妇科生殖内分泌疾患,我国育龄期人群PCOS的患病率为5.61%[1]。本病临床主要表现为月经稀发、不孕、痤疮、多毛等,不仅影响女性正常的排卵、月经和生育功能,还会造成代谢综... 详细信息

多囊卵巢综合征(polycystic ovary syndrome,PCOS)是临床常见的妇科生殖内分泌疾患,我国育龄期人群PCOS的患病率为5.61%[1]。本病临床主要表现为月经稀发、不孕、痤疮、多毛等,不仅影响女性正常的排卵、月经和生育功能,还会造成代谢综合征、妊娠期糖尿病、胎儿生长受限、早产等多种远期并发症[2]。且PCOS患者长期无排卵,使子宫内膜受单一雌激素的刺激不断增生,子宫内膜癌发生风险较正常女性高出4倍[3]。育龄期是PCOS发病的主要阶段,也是女性生育的关键时期,因此,对本病尽早干预具有重要意义[4]。

关键词：多囊卵巢综合征非超重型中药优思明疗效观察

A Highly Efficient and Selective Water-Soluble Bimetallic Catalyst for Hydrogenation of Chloronitrobenzene to Chloroaniline

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China Petroleum Processing & Petrochemical Technology 2015年第2期17卷 26-31页

作者： Zhou yafen yang Wenjuan Zhou Limei Wang Ma.ma. ma Xiaoyan Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province College of Chemistry and Chemical Engineering China West Normal University College of materials and Chemistry & Chemical Engineering Chengdu University of Technology

Selective hydrogenation of chloronitrobenzene(CNB) to chloroaniline(CAN) catalyzed by water-soluble Ru/Pt bimetallic catalyst in an aqueous-organic biphasic system was studied. It was found that the catalytic activity increased obviously due to the addition of platinum. Ru/Pt bimetallic catalysts exhibited a strong synergistic effect when the molar ratio of Pt was in the range of 5%—80%. Under the mild conditions including a temperature of 25 ℃, a hydrogen pressure of 1.0 MPa and a Pt molar ratio of 20%, the conversion of p-chloronitrobenzene(p-CNB) reached 99.9%, with the selectivity to p-chloroaniline(p-CAN) equating to 99.4%. The Ru/Pt catalyst also showed high activity and selectivity for the hydrogenation of other chloro- and dichloro-nitrobenzenes with different substituted positions. In addition, the catalyst can be recycled five times without significant loss of activity.

关键词： water-soluble bimetallic catalyst hydrogenation chloronitrobenzene chloroaniline