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基于DPsIR模型的秦岭北麓陕西城市群水安全评估及驱动因子识别

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地球科学与环境学报 2024年第2期46卷 143-153页

作者：徐盼盼陈硕马浩苑蒋玉成冯靖陈洁钱会长安大学水利与环境学院陕西西安710054 长安大学旱区地下水文与生态效应教育部重点实验室陕西西安710054 长安大学水利部旱区生态水文与水安全重点实验室陕西西安710054 长安大学秦岭生态环境研究院陕西西安710054

水安全评估是水资源开发利用与区域发展的基础。为了加强秦岭北麓陕西城市群可持续建设,助力秦岭“中央水塔”绿色发展,基于DPsIR模型构建秦岭北麓陕西城市群水安全评估体系,结合主客观综合赋权法与模糊综合评价法对区域2011~2021年水... 详细信息

水安全评估是水资源开发利用与区域发展的基础。为了加强秦岭北麓陕西城市群可持续建设,助力秦岭“中央水塔”绿色发展,基于DPsIR模型构建秦岭北麓陕西城市群水安全评估体系,结合主客观综合赋权法与模糊综合评价法对区域2011~2021年水安全进行评估分级,并利用灰色关联度法分析其水安全的驱动因子。结果表明:秦岭北麓陕西城市群2011~2021年水安全状态变化具有一致性,波动中稳步提升。西安市水安全等级相较宝鸡市、渭南市上升趋势显著,于2021年转为无警状态;宝鸡市一直保持低警状态,而渭南市长期处于中警状态。陕西城市群的水安全状态及发展趋势与人均GDP、年降水量、人均用水量等10个驱动因子密切相关,其中经济因子是水安全等级呈现一致性的根本保证,社会和生态因子则是造成水安全差异性的主要原因。

关键词：水安全驱动因子 DPsIR模型灰色关联度法城市群秦岭陕西

Officials'Foreign Experience and Firms'Exports:Evidence from China

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China & World Economy 2023年第3期31卷 173-204页

作者： Yekun Xu Guangyuan ma Lijuan Cui Business school Liaoning UniversityChina school of Accountancy Shanghai University of Finance and EconomicsChina school of Economics Zhejiang UniversityChina.

This study examines how the foreign experience of local oficials affects firms'exports in *** a matched sample from 2000 to 2012,we found that the foreign experience of municipal Party secretaries had a significant impact on the promotion of firms'exports,especially for private *** positive impact was more pronounced when officials went abroad at a younger age,stayed abroad for a longer period,returned to China for a longer time,and had greater promotion *** found that officials'foreign experience helped to mitigate the negative impact of institutional distance and provided firms with better access to export subsidies,both of which could promote *** was also a complementary effect when officials and executives both had foreign ***,our study provides some insights into the economic outcomes of officials'foreign experience and sheds light on the export performance of Chinese firms.

关键词： firm exports foreign experience institutional distance learning effect local officials

Formation and Collapse of Cellulose Nanocrystals and Hydrophobic Association-induced Dual Cross-linked Nanocomposite Hydrogels: A Rheological study

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Paper And Biomaterials 2022年第3期7卷 19-29页

作者： Xiaorui Jin Mingguo ma Jun Yang Beijing Key Laboratory of Lignocellulosic Chemistry College of Materials Science and TechnologyBeijing Forestry UniversityBeijing100083China

The rheological characteristics of a physical gelation system,in which cellulose nanocrystals(CNC_(s))induced the entanglement of poly(acrylic acid)(PAA)chains and partial hydrophobic association of octylphenol polyoxyethylene acrylate(OP-10-AC)branches in a micellar solution of sodium dodecyl sulfate(sDs),were *** gelation time of the physical gels decreased as the CNC content and number of hydrophobic branch units *** the gel point,the storage modulus(G')and loss modulus(G")followed the same frequency dependence(G'≈G"≈ωn),where the hydrophobic moieties attached to the side chains had a significant impact on the values of viscoelastic exponent(n).Beyond the gel point,the initial polymer solution was transformed to a solid-like gel,and the strength of the gel network was governed by associations between both the CNCs and hydrophobic *** evolution of the viscoelasticity during the gel-sol transition was monitored,demonstrating that due to a reversible arrangement of the hydrophobic units,a large proportion of physical cross-links dissociated under a thermal trigger and were reversibly reformed when the solution was cooled,while no such partial recovery was observed in the case of the single CNC-induced network systems(with no hydrophobic branches).

关键词： hydrogels cellulose nanocrystals hydrophobic association rheology

Content Feature Extraction-based Hybrid Recommendation for Mobile Application services

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Computers, materials & Continua 2022年第6期71卷 6201-6217页

作者： Chao ma Yinggangsun Zhenguo Yang Hai Huang Dongyang Zhan Jiaxing Qu Harbin University of science and Technology Harbin150040China Harbin Institute of Technology Harbin150001China The Ohio state University Columbus43202USA Heilongjiang Province Cyberspace Research Center Harbin150001China

The number of mobile application services is showing an explosive growth trend,which makes it difficult for users to determine which ones are of ***,the new mobile application services are emerge continuously,most of them have not be rated when they need to be recommended to *** is the typical problem of cold start in the field of collaborative filtering *** problem may makes it difficult for users to locate and acquire the services that they actually want,and the accuracy and novelty of service recommendations are also difficult to satisfy *** solve this problem,a hybrid recommendation method for mobile application services based on content feature extraction is proposed in this ***,the proposed method in this paper extracts service content features through Natural Language Processing technologies such as word segmentation,part-of-speech tagging,and dependency *** improves the accuracy of describing service attributes and the rationality of the method of calculating service ***,a language representation model called Bidirectional Encoder Representation from Transformers(BERT)is used to vectorize the content feature text,and an improved weighted word mover’s distance algorithm based on Term Frequency-Inverse Document Frequency(TFIDF-WMD)is used to calculate the similarity of mobile application ***,the recommendation process is completed by combining the item-based collaborative filtering recommendation *** experimental results show that by using the proposed hybrid recommendation method presented in this paper,the cold start problem is alleviated to a certain extent,and the accuracy of the recommendation result has been significantly improved.

关键词： service recommendation cold start feature extraction natural language processing word mover’s distance

胶州湾大沽河河口湿地中的水鸟资源调查与动态分析

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湿地科学 2024年第1期22卷 52-59页

作者：邢玲玲薛琳于涛徐克阳林月婷石建伟马士胜中国海洋大学海洋生命学院山东青岛266003 青岛市观鸟协会山东青岛100012 青岛市园林和林业局山东青岛266100 胶州市自然资源和规划局山东胶州266300

胶州湾大沽河河口湿地是水鸟南、北迁徙路线上的重要停歇地。2019年至2021年期间,在大沽河河口湿地中,开展了水鸟资源调查,建立了水鸟物种名录,研究了水鸟物种数量和个体数量的月变化;利用3种多样性指数,分析了水鸟群落的多样性。研究... 详细信息

胶州湾大沽河河口湿地是水鸟南、北迁徙路线上的重要停歇地。2019年至2021年期间,在大沽河河口湿地中,开展了水鸟资源调查,建立了水鸟物种名录,研究了水鸟物种数量和个体数量的月变化;利用3种多样性指数,分析了水鸟群落的多样性。研究结果表明,调查期间,在大沽河河口湿地中,记录了96种水鸟,隶属于6目14科,其中,鸻形目水鸟的物种数量和个体数量都最多;在96种水鸟中,青头潜鸭(Aythya baeri)、小青脚鹬(Tringa guttifer)、黑嘴鸥(saundersilarus saundersi)、遗鸥(Ichthyaetus relictus)、中华凤头燕鸥(Thalasseus bernsteini)和黄嘴白鹭(Egretta eulophotes)共6种水鸟为国家一级重点保护野生鸟类,大天鹅(Cygnus cygnus)、白额雁(Anser albifrons)、花脸鸭(sibirionetta formosa)、斑头秋沙鸭(Mergellus albellus)、灰鹤(Grus grus)、白腰杓鹬(Numenius arquata)、大杓鹬(Numenius madagascariensis)、翻石鹬(Arenaria interpres)、半蹼鹬(Limnodromus semipalmatus)、大滨鹬(Calidris tenuirostris)、阔嘴鹬(Calidris falcinellus)、黑颈??(Podiceps nigricollis)和白琵鹭(Platalea leucorodia)共13种水鸟为国家二级重点保护野生鸟类;2019年、2020年和2021年,大沽河河口湿地中的水鸟物种总数量分别为80种、87种和74种,水鸟个体的总数量分别为148213只、141388只和84471只;2021年水鸟群落的shannon-Wiener多样性指数值(3.438)和Pielou均匀度指数值(0.554)都分别最大,2020年水鸟群落的simpson优势度指数值(0.219)最大;2019年、2020年和2021年,胶州湾大沽河河口湿地中水鸟群落的优势物种都为翘鼻麻鸭(Tadorna tadorna)、黑腹滨鹬(Calidris alpina)和灰斑鸻(Pluvialis squatarola);未来,在大沽河河口湿地中,要加大水鸟资源的调查范围和力度,以获得更全面的该湿地中水鸟资源的数据,了解水鸟对生存环境的选择,减少人类活动对水鸟的干扰。

关键词：水鸟资源动态大沽河河口湿地胶州湾

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造口旁疝发生危险因素Meta分析

中国现代普通外科进展 2024年第6期27卷 463-470页

作者：王开雷马丽娜卜广波张广东樊辉于斐杜恒锐马刚济宁医学院附属滕州市中心人民医院胃肠外科山东滕州277500

目的:运用Meta分析评价造口旁疝(PsH)形成的危险因素,为防治PsH提供理论基础。方法:通过检索PubMed、中国知网、万方数据等数据库,收集PsH危险因素的病例对照或队列研究。提取相关数据,使用Revman 5.3进行Meta分析。结果:共纳入16个研究... 详细信息

目的:运用Meta分析评价造口旁疝(PsH)形成的危险因素,为防治PsH提供理论基础。方法:通过检索PubMed、中国知网、万方数据等数据库,收集PsH危险因素的病例对照或队列研究。提取相关数据,使用Revman 5.3进行Meta分析。结果:共纳入16个研究,总样本量2411例,累计PsH组670例,非PsH组1741例。分析结果显示高龄、女性、BMI≥25、高血压、慢性阻塞性肺疾病(COPD)/慢性咳嗽、糖尿病、术后低蛋白血症可增加PsH的发生风险(PsH的发生无明显关系(P>0.05)。结论:当前证据表明高龄、女性、MBI≥25、高血压、COPD/慢性咳嗽、糖尿病、术后低蛋白血症是PsH的危险因素,而经腹膜外造口可降低PsH的发生。

关键词：造口旁疝危险因素 Meta分析

Enhancing photostability and power conversion efficiency of organic solar cells by a “sunscreen” ternary strategy

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science China Chemistry 2023年第4期66卷 1179-1189页

作者： Yongjie Cui Zeng Chen Peipei Zhu Wei ma Haiming Zhu Xunfan Liao Yiwang Chen state Key Laboratory for Modification of Chemical Fibers and Polymer materials&College of materials science and Engineering Donghua UniversityShanghai 201620China National Engineering Research Center for Carbohydrate synthesis/Key Lab of Fluorine and silicon for Energy materials and Chemistry of Ministry of Education Jiangxi Normal UniversityNanchang 330022China Center for Chemistry of High-Performance and Novel materials Department of ChemistryZhejiang UniversityHangzhou 310027China state Key Laboratory for Mechanical Behavior of materials Xi'an Jiaotong UniversityXi'an 710049China

The field has witnessed the rapid growth in the power conversion efficiency(PCE)of organic solar cells(OsCs)over the past decade,reaching the threshold for practical ***,a major issue remains that OsC lifetimes are seriously limited by the ultraviolet(UV)-induced ***,inspired by the superior photostability of car paint under sunlight and ambient air,a“sunscreen”molecule,2-(2-hydroxy-5-tert-octylphenyl)benzotriazole(UV329),is used to construct the PM6:Y6 ternary *** addition of UV329 mainly enhances the ordered stacking of PM6 and increases the light utilization of blend films with the improved crystallization and appropriate phase ***,the ternary device exhibits stronger light response and obviously higher and more balanced carrier mobilities,contributing to higher short-circuit current density,fill factor and *** PCE boost is also verified in PM6:BTP-e C9 and PM6:L8-BO *** photodegradation of PM6 dominates the photo-degradation process of PM6:Y6 systems,while the UV329 can effectively suppress such degradation,and thus the ternary device can retain nearly 90%of the initial PCE under continuous illumination for 120 ***,ternary devices also preserve better thermal stability and shelf-life with the enhanced *** work provides a simple yet effective strategy for simultaneously improving PCE and photostability of OsCs.

关键词： ternary strategy sunscreen UV absorber photostability organic solar cells

Qos-Aware Cloud service Optimization Algorithm in Cloud manufacturing Environment

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Intelligent Automation & soft Computing 2023年第8期37卷 1499-1512页

作者： Wenlong ma Youhong Xu Jianwei Zheng sadaqat ur Rehman school of Information Engineering Quzhou College of TechnologyQuzhou324000China school of Computer science and Technology Zhejiang University of TechnologyHangzhou310023China Department of Natural and Computing science University of AberdeenScotlandAberdeenAB243FXUK

In a cloud manufacturing environment with abundant functionally equivalent cloud services,users naturally desire the highest-quality service(s).Thus,a comprehensive measurement of quality of service(Qos)is ***-mizing the plethora of cloud services has thus become a top *** ser-vice optimization is negatively affected by untrusted Qos data,which are inevitably provided by some *** resolve these problems,this paper proposes a Qos-aware cloud service optimization model and establishes Qos-information awareness and quantiﬁcation *** data are assessed by an information correction *** weights discovered by the variable precision Rough set,which mined the evaluation indicators from historical data,providing a comprehensive performance ranking of service *** manufacturing cloud service optimization algorithm thus provides a quantitative reference for service *** experimental simulations,this method recommended the optimal services that met users’needs,and effectively reduced the impact of dis-honest users on the selection results.

关键词： Cloud manufacturing quality of service optimization algorithm rough set

区域折射型人工晶状体植入术后角膜残余散光对患者视觉质量的影响

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眼科新进展 2024年第1期44卷 43-47页

作者：马晓婷李科军赵智华张茵杜颖华梁福珍河北省人民医院眼科河北省石家庄市050057 北京天坛医院眼科北京市100050 河北医科大学河北省石家庄市050011

目的探讨区域折射型人工晶状体植入术后角膜残余散光对患者视觉质量的影响。方法回顾性队列研究。收集2020年6月至2022年3月在河北省人民医院眼科行白内障超声乳化摘除联合LENTIs Comfort Ls-313 MF15人工晶状体植入术的白内障患者57例... 详细信息

目的探讨区域折射型人工晶状体植入术后角膜残余散光对患者视觉质量的影响。方法回顾性队列研究。收集2020年6月至2022年3月在河北省人民医院眼科行白内障超声乳化摘除联合LENTIs Comfort Ls-313 MF15人工晶状体植入术的白内障患者57例(73眼)的病历及随访资料,将其按照术后角膜残余散光进行分组,角膜残余散光>0.75~1.50 D的患者32例40眼作为试验组,角膜残余散光≤0.75 D的患者25例33眼作为对照组。记录两组患者术后6个月的裸眼远距离视力(5 m)、裸眼中距离视力(80 cm)、裸眼近距离视力(40 cm)、离焦曲线、客观视觉质量、主观视觉质量、满意度及脱镜率。结果试验组与对照组患者术后裸眼远距离视力(logmaR)均为0.10(0.00,0.22),裸眼中距离视力(logmaR)均为0.00(0.00,0.10),裸眼近距离视力(logmaR)分别为0.20(0.10,0.30)、0.20(0.10,0.20),两组患者间比较差异均无统计学意义(均为P>0.05)。术后离焦曲线显示,附加球镜度数从+2.00 D至-4.00 D的不同屈光度数上的远距离视力两组患者间相比差异均无统计学意义(均为P>0.05)。两组患者术后客观视觉质量中总像差、彗差、调制传递函数及斯特列尔比值相比差异均有统计学意义(均为P0.05)。两组患者间主观视觉质量、满意度及脱镜率相比差异均无统计学意义(均为P>0.05)。结论LENTIs Comfort Ls-313 MF15人工晶状体植入术后0.75~1.50 D的角膜残余散光对患者主观视觉质量及客观视觉质量中总高阶像差、球差及三叶草差没有影响,对客观视觉质量中总像差、彗差、调制传递函数及斯特列尔比值有影响。

关键词：散光视觉质量区域折射型人工晶状体

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