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基于BSC的基础设施PPP项目绩效评估研究
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作者 高华 薛亚捧 褚瑞 《建筑经济》 2024年第9期48-54,共7页
结合基础设施项目的特征及PPP模式的特点,运用平衡计分卡对基础设施PPP项目绩效进行评价,确立了财务与融资、利益相关者、内部控制及风险管理和可持续发展四个维度的评价指标,并以海南龙华区图书馆PPP项目为例进行评价,验证了评价指标... 结合基础设施项目的特征及PPP模式的特点,运用平衡计分卡对基础设施PPP项目绩效进行评价,确立了财务与融资、利益相关者、内部控制及风险管理和可持续发展四个维度的评价指标,并以海南龙华区图书馆PPP项目为例进行评价,验证了评价指标设计的合理性以及方法的可行性。 展开更多
关键词 基础设施 PPP模式 绩效评估 bsc
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基于EVA-BSC的物流企业财务绩效评价研究
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作者 罗艳妮 闫润楠 杨佩瑶 《中国储运》 2024年第6期148-149,共2页
本文充分利用EVA(Economic Value Added,经济增加值)和BSC(Balanced Score Card,平衡记分卡)的优势,设计了一种以物流企业为核心的财务绩效评价方法,并以实际的数据为基础,分析测试了设计评价方法的可靠性。1.物流企业财务绩效评价方法... 本文充分利用EVA(Economic Value Added,经济增加值)和BSC(Balanced Score Card,平衡记分卡)的优势,设计了一种以物流企业为核心的财务绩效评价方法,并以实际的数据为基础,分析测试了设计评价方法的可靠性。1.物流企业财务绩效评价方法设计1.1基于BSC的物流企业财务绩效考核体系构建。为了确保构建的BSC绩效考核体系能够全面覆盖企业战略本文将对企业发展起到关键性与决定性的战略要素进行综合分析,充分考虑了管理体制调整战略下,企业建立现代企业制度和科学管理体制,提高核心竞争力的目标,以及竞争战略下. 展开更多
关键词 财务绩效评价 战略要素 企业财务绩效 物流企业 平衡记分卡 绩效考核体系 bsc 竞争战略
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Inverse design of mechanical metamaterial achieving a prescribedconstitutive curve 被引量:1
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作者 Zongliang Du Tanghuai Bian +4 位作者 Xiaoqiang Ren Yibo Jia Shan Tang Tianchen Cui Xu Guo 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第1期16-22,共7页
Besides exhibiting excellent capabilities such as energy absorption,phase-transforming metamaterials offer a vast design space for achieving nonlinear constitutive relations.This is facilitated by switching between di... Besides exhibiting excellent capabilities such as energy absorption,phase-transforming metamaterials offer a vast design space for achieving nonlinear constitutive relations.This is facilitated by switching between different patterns under deformation.However,the related inverse design problem is quite challenging,due to the lack of appropriate mathematical formulation and the convergence issue in the post-buckling analysis of intermediate designs.In this work,periodic unit cells are explicitly described by the moving morphable voids method and effectively analyzed by eliminating the degrees of freedom in void regions.Furthermore,by exploring the Pareto frontiers between error and cost,an inverse design formulation is proposed for unit cells.This formulation aims to achieve a prescribed constitutive curve and is validated through numerical examples and experimental results.The design approach presented here can be extended to the inverse design of other types of mechanical metamaterials with prescribed nonlinear effective properties. 展开更多
关键词 METAMATERIAL Pattern-transformation Constitutive curve Inverse design
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A comparative study of data-driven battery capacity estimation based on partial charging curves 被引量:1
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作者 Chuanping Lin Jun Xu +5 位作者 Delong Jiang Jiayang Hou Ying Liang Xianggong Zhang Enhu Li Xuesong Mei 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期409-420,I0010,共13页
With its generality and practicality, the combination of partial charging curves and machine learning(ML) for battery capacity estimation has attracted widespread attention. However, a clear classification,fair compar... With its generality and practicality, the combination of partial charging curves and machine learning(ML) for battery capacity estimation has attracted widespread attention. However, a clear classification,fair comparison, and performance rationalization of these methods are lacking, due to the scattered existing studies. To address these issues, we develop 20 capacity estimation methods from three perspectives:charging sequence construction, input forms, and ML models. 22,582 charging curves are generated from 44 cells with different battery chemistry and operating conditions to validate the performance. Through comprehensive and unbiased comparison, the long short-term memory(LSTM) based neural network exhibits the best accuracy and robustness. Across all 6503 tested samples, the mean absolute percentage error(MAPE) for capacity estimation using LSTM is 0.61%, with a maximum error of only 3.94%. Even with the addition of 3 m V voltage noise or the extension of sampling intervals to 60 s, the average MAPE remains below 2%. Furthermore, the charging sequences are provided with physical explanations related to battery degradation to enhance confidence in their application. Recommendations for using other competitive methods are also presented. This work provides valuable insights and guidance for estimating battery capacity based on partial charging curves. 展开更多
关键词 Lithium-ion battery Partial charging curves Capacity estimation DATA-DRIVEN Sampling frequency
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A dynamic soil freezing characteristic curve model for frozen soil 被引量:1
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作者 Xiaokang Li Xu Li Jiankun Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期3339-3352,共14页
The soil freezing characteristic curve(SFCC)plays a fundamental role in comprehending thermohydraulic behavior and numerical simulation of frozen soil.This study proposes a dynamic model to uniformly express SFCCs ami... The soil freezing characteristic curve(SFCC)plays a fundamental role in comprehending thermohydraulic behavior and numerical simulation of frozen soil.This study proposes a dynamic model to uniformly express SFCCs amidst varying total water contents throughout the freezing-thawing process.Firstly,a general model is proposed,wherein the unfrozen water content at arbitrary temperature is determined as the lesser of the current total water content and the reference value derived from saturated SFCC.The dynamic performance of this model is verified through test data.Subsequently,in accordance with electric double layer(EDL)theory,the theoretical residual and minimum temperatures in SFCC are calculated to be-14.5℃to-20℃for clay particles and-260℃,respectively.To ensure that the SFCC curve ends at minimum temperature,a correction function is introduced into the general model.Furthermore,a simplified dynamic model is proposed and investigated,necessitating only three parameters inherited from the general model.Additionally,both general and simplified models are evaluated based on a test database and proven to fit the test data exactly across the entire temperature range.Typical recommended parameter values for various types of soils are summarized.Overall,this study provides not only a theoretical basis for most empirical equations but also proposes a new and more general equation to describe the SFCC. 展开更多
关键词 Frozen soils Unsaturated soils Soil freezing characteristic curve(SFCC) Mathematic models
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EVA-BSC在P出版社绩效评价中的应用研究
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作者 王伟 刘军峰 《西安石油大学学报(社会科学版)》 2024年第5期75-82,共8页
以P行业出版社为评价对象,基于EVA-BSC,在“财务评价+社会绩效”分离式的业绩评价的基础上构建P出版社绩效评价体系。实证结果表明:基于EVA-BSC的绩效评价体系较为全面地反映了该出版社的真实运营状况,突出了企业的战略引导评价和社会... 以P行业出版社为评价对象,基于EVA-BSC,在“财务评价+社会绩效”分离式的业绩评价的基础上构建P出版社绩效评价体系。实证结果表明:基于EVA-BSC的绩效评价体系较为全面地反映了该出版社的真实运营状况,突出了企业的战略引导评价和社会责任担当。建议结合动态赋权对该评价体系进行实际应用,其具有较高的环境适应性。 展开更多
关键词 EVA-bsc 绩效评价 行业出版社 模糊综合评判法
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基于绩效棱柱-BSC的绿色会计信息披露问题—一个煤炭行业的多案例对比研究
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作者 黄琦华 曹湘平 《中文科技期刊数据库(全文版)经济管理》 2024年第11期0122-0126,共5页
基于绩效棱柱-BSC模型,将利益相关者等5大层面、客户等4大维度以及产品碳排放量等12项指标层融于一体,构建出我国煤炭行业绿色会计信息披露体系,并通过对前10大上市煤炭公司的披露方式、披露质量及披露内容进行多案例比较研究。研究结... 基于绩效棱柱-BSC模型,将利益相关者等5大层面、客户等4大维度以及产品碳排放量等12项指标层融于一体,构建出我国煤炭行业绿色会计信息披露体系,并通过对前10大上市煤炭公司的披露方式、披露质量及披露内容进行多案例比较研究。研究结果显示,当前我国煤炭行业绿色会计信息披露存在不及时、披露质量参差不齐、披露方式不统一、披露审计缺失等诸多问题,并针对性地提出了相应解决措施,本研究旨在为相关政策制定者和企业管理者提供决策依据,帮助行业企业实现在经济、环境和社会维度高质量协同发展。 展开更多
关键词 绩效棱柱 bsc模型 绿色会计 信息披露 优化建议
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健康中国背景下BSC在三级公立医院绩效考核体系优化研究
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作者 杨可钦 张金朋 刘跟莉 《中国乡镇企业会计》 2024年第4期115-117,共3页
随着医疗卫生体制改革至今,医疗健康事业取得了阶段性成果,我国基本医疗卫生制度已初步建立,同时也迎来了人口老龄化、群众看病就医难等新的挑战。在“健康中国2030”的大背景下,如何构建合理的绩效考核体系,是三级公立医院的改革方向... 随着医疗卫生体制改革至今,医疗健康事业取得了阶段性成果,我国基本医疗卫生制度已初步建立,同时也迎来了人口老龄化、群众看病就医难等新的挑战。在“健康中国2030”的大背景下,如何构建合理的绩效考核体系,是三级公立医院的改革方向。平衡计分卡法(BSC)是一种绩效管理工具,具有综合性、精准性等特点,在国外应用广泛,如何将平衡计分卡法应用于三级公立医院的绩效考核,优化绩效考核体系,具有现实意义。本文通过健康中国背景下BSC在三级公立医院绩效考核体系优化研究,将“健康中国2030”背景下的三级公立医院存在的问题进行分析,优化平衡计分卡在三级公立医院绩效体系的应用,并提出一定的实施方案与细则,希望为公立医院深化绩效体系改革提供帮助与支持。 展开更多
关键词 健康中国 公立医院绩效考核 bsc
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Method for determining the position of landslide slip-surface with a typical inclinometric curves
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作者 CHEN Hao WU Hong-gang 《Journal of Mountain Science》 SCIE CSCD 2024年第2期413-432,共20页
In the actual monitoring of deep hole displacement,the identification of slip surfaces is primarily based on abrupt changes observed in the inclinometric curve.In conventional identification methods,inclinometric curv... In the actual monitoring of deep hole displacement,the identification of slip surfaces is primarily based on abrupt changes observed in the inclinometric curve.In conventional identification methods,inclinometric curves exhibiting indications of sliding can be categorized into three types:B-type,D-type,and r-type.The position of the slip surface is typically determined by identifying the depth corresponding to the point of maximum displacement mutation.However,this method is sensitive to the interval of measurement points and the observation scale of the coordinate axes and suffers from unclear sliding surfaces and uncertain values.Based on the variation characteristics of these diagonal curves,we classified the landslide into three components:the sliding body,the sliding interval,and the immobile body.Moreover,three different generalization models were established to analyze the relationships between the curve form and the slip surface location based on different physical indicators such as displacement rate,relative displacement,and acceleration.The results show that the displacement rate curves of an r-type slope exhibit a clustering feature in the sliding interval,and by solving for the depth of discrete points within the step phase,it is possible to determine the location of the slip surface.On the other hand,D-type slopes have inflection points in the relative displacement curve located at the slip surface.The acceleration curves of B-type slopes exhibit clustering characteristics during the sliding interval,while the scattered acceleration data demonstrate wandering characteristics.Consequently,the slip surface location can be revealed by solving the depth corresponding to the maximum acceleration with cubic spline interpolation.The approach proposed in this paper was applied to the monitoring data of a landslide in Yunnan Province,China.The results indicate that our approach can accurately identify the slip surface location and enable computability of its position,thereby enhancing applicability and reliability of the deep-hole displacement monitoring data. 展开更多
关键词 Inclinometric curve Slip-surface position Displacement rate Relative displacement Acceleration
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Research into Applicability of Wöhler Curve Method for Low-Cycle Fatigue of Metallic Materials
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作者 Xiangqiao Yan 《Journal of Harbin Institute of Technology(New Series)》 CAS 2024年第2期22-37,共16页
Recently,a description on a practicability of the Wöhler Curve Method for low-cycle fatigue of metals was given by the author.By the description and the low cycle fatigue test data of 16 MnR steel,it is important... Recently,a description on a practicability of the Wöhler Curve Method for low-cycle fatigue of metals was given by the author.By the description and the low cycle fatigue test data of 16 MnR steel,it is important to show that,for low cycle fatigue of metals,such a way that a stress-based intensity parameter calculated by the linear-elastic analysis is taken to be a stress intensity parameter,S,to establish a relationship between the stress intensity parameter,S,and the fatigue life,N,is practicable.In this paper,many metallic materials from the literature are given to show that the Wöhler Curve Method is well suitable for low-cycle fatigue analysis of metals. 展开更多
关键词 low cycle fatigue Wöhler curve method coffin-manson curve method METALS
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Research on batch multielement rapid quantitative analysis based on the standard curve-assisted calibration-free laserinduced breakdown spectroscopy method
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作者 Weiwei HAN Duixiong SUN +7 位作者 Guoding ZHANG Honglin WANG Kai GUO Yuzhuo ZHANG Haoliang WANG Denghong ZHANG Chenzhong DONG Maogen SU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第9期156-164,共9页
This study proposes a batch rapid quantitative analysis method for multiple elements by combining the advantages of standard curve(SC)and calibration-free laser-induced breakdown spectroscopy(CF-LIBS)technology to ach... This study proposes a batch rapid quantitative analysis method for multiple elements by combining the advantages of standard curve(SC)and calibration-free laser-induced breakdown spectroscopy(CF-LIBS)technology to achieve synchronous,rapid,and accurate measurement of elements in a large number of samples,namely,SC-assisted CF-LIBS.Al alloy standard samples,divided into calibration and test samples,were applied to validate the proposed method.SC was built based on the characteristic line of Pb and Cr in the calibration sample,and the contents of Pb and Cr in the test sample were calculated with relative errors of 6%and 4%,respectively.SC built using Cr with multiple characteristic lines yielded better calculation results.The relative contents of ten elements in the test sample were calculated using CF-LIBS.Subsequently,the SC-assisted CF-LIBS was executed,with the majority of the calculation relative errors falling within the range of 2%-5%.Finally,the Al and Na contents of the Al alloy were predicted.The results demonstrate that it effectively enables the rapid and accurate quantitative analysis of multiple elements after a single-element SC analysis of the tested samples.Furthermore,this quantitative analysis method was successfully applied to soil and Astragalus samples,realizing an accurate calculation of the contents of multiple elements.Thus,it is important to advance the LIBS quantitative analysis and its related applications. 展开更多
关键词 laser-induced breakdown spectroscopy standard curve quantitative analysis multielement
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Deep structure of the Southeast Asian curved subduction system and its dynamic process
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作者 Weiwei DING 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期701-704,共4页
The deep structure,material circulation,and dynamic processes in the Southeast Asia have long been an elusive scientific puzzle due to the lack of systematic scientific observations and recognized theoretical models.B... The deep structure,material circulation,and dynamic processes in the Southeast Asia have long been an elusive scientific puzzle due to the lack of systematic scientific observations and recognized theoretical models.Based on the deep seismic tomography using long-period natural earthquake data,in this study,the deep structure and material circulation of the curved subduction system in Southeast Asia was studied,and the dynamic processes since 100 million years ago was reconstructed.It is pointed out that challenges still exist in the precise reconstruction of deep mantle structures of the study area,the influence of multi-stage subduction on deep material exchange and shallow magma activity,as well as the spatiotemporal evolution and coupling mechanism of multi-plate convergence.Future work should focus on high-resolution land-sea joint 3-D seismic tomography imaging of the curved subduction system in the Southeast Asia,combined with geochemical analysis and geodynamic modelling works. 展开更多
关键词 curved subduction system deep structure material recycling dynamic process Southeast Asia
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Quantum dynamics within curved thin layers with deviation
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作者 程润 赵浩 +4 位作者 罗翠柏 周璇 王必利 李延标 王骏 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期502-507,共6页
Combining the deviation between thin layers' adjacent surfaces with the confining potential method applied to the quantum curved systems,we derive the effective Schr?dinger equation describing the particle constra... Combining the deviation between thin layers' adjacent surfaces with the confining potential method applied to the quantum curved systems,we derive the effective Schr?dinger equation describing the particle constrained within a curved layer,accompanied by a general geometric potential V_(gq) composed of a compression-corrected geometric potential V_(gq)~*and a novel potential V_(gq)~(**) brought by the deviation.Applying this analysis to the cylindrical layer emerges two types of deviation-induced geometric potential,resulting from the the cases of slant deviation and tangent deviation,respectively,which strongly renormalizes the purely geometric potential and contribute to the energy spectrum based on a very substantial deepening of bound states they offer. 展开更多
关键词 confining potential method quantum mechanics curved thin layer
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A Non-Parametric Scheme for Identifying Data Characteristic Based on Curve Similarity Matching
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作者 Quanbo Ge Yang Cheng +3 位作者 Hong Li Ziyi Ye Yi Zhu Gang Yao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1424-1437,共14页
For accurately identifying the distribution charac-teristic of Gaussian-like noises in unmanned aerial vehicle(UAV)state estimation,this paper proposes a non-parametric scheme based on curve similarity matching.In the... For accurately identifying the distribution charac-teristic of Gaussian-like noises in unmanned aerial vehicle(UAV)state estimation,this paper proposes a non-parametric scheme based on curve similarity matching.In the framework of the pro-posed scheme,a Parzen window(kernel density estimation,KDE)method on sliding window technology is applied for roughly esti-mating the sample probability density,a precise data probability density function(PDF)model is constructed with the least square method on K-fold cross validation,and the testing result based on evaluation method is obtained based on some data characteristic analyses of curve shape,abruptness and symmetry.Some com-parison simulations with classical methods and UAV flight exper-iment shows that the proposed scheme has higher recognition accuracy than classical methods for some kinds of Gaussian-like data,which provides better reference for the design of Kalman filter(KF)in complex water environment. 展开更多
关键词 curve similarity matching Gaussian-like noise non-parametric scheme parzen window.
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Bending results of graphene origami reinforced doubly curved shell
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作者 Nan Yang Yunhe Zou Mohammad Arefi 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第5期198-210,共13页
The present work investigates higher order stress,strain and deformation analyses of a shear deformable doubly curved shell manufactures by a Copper(Cu)core reinforced with graphene origami auxetic metamaterial subjec... The present work investigates higher order stress,strain and deformation analyses of a shear deformable doubly curved shell manufactures by a Copper(Cu)core reinforced with graphene origami auxetic metamaterial subjected to mechanical and thermal loads.The effective material properties of the graphene origami auxetic reinforced Cu matrix are developed using micromechanical models cooperate both material properties of graphene and Cu in terms of temperature,volume fraction and folding degree.The principle of virtual work is used to derive governing equations with accounting thermal loading.The numerical results are analytically obtained using Navier's technique to investigate impact of significant parameters such as thermal loading,graphene amount,folding degree and directional coordinate on the stress,strain and deformation responses of the structure.The graphene origami materials may be used in aerospace vehicles and structures and defence technology because of their low weight and high stiffness.A verification study is presented for approving the formulation,solution methodology and numerical results. 展开更多
关键词 Graphene origami Copper matrix Doubly curved Shear deformable Auxetic metamaterial
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A Tutorial Review of the Solar Power Curve: Regressions, Model Chains, and Their Hybridization and Probabilistic Extensions
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作者 Dazhi YANG Xiang’ao XIA Martin János MAYER 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1023-1067,共45页
Owing to the persisting hype in pushing toward global carbon neutrality,the study scope of atmospheric science is rapidly expanding.Among numerous trending topics,energy meteorology has been attracting the most attent... Owing to the persisting hype in pushing toward global carbon neutrality,the study scope of atmospheric science is rapidly expanding.Among numerous trending topics,energy meteorology has been attracting the most attention hitherto.One essential skill of solar energy meteorologists is solar power curve modeling,which seeks to map irradiance and auxiliary weather variables to solar power,by statistical and/or physical means.In this regard,this tutorial review aims to deliver a complete overview of those fundamental scientific and engineering principles pertaining to the solar power curve.Solar power curves can be modeled in two primary ways,one of regression and the other of model chain.Both classes of modeling approaches,alongside their hybridization and probabilistic extensions,which allow accuracy improvement and uncertainty quantification,are scrutinized and contrasted thoroughly in this review. 展开更多
关键词 review energy meteorology solar power curve model chain solar power prediction
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Current Status and Perspectives of External Versus Internal Pancreatic Duct Drainage during the Learning Curve of Laparoscopic Pancreaticoduodenectomy
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作者 Shicheng Gong Shijia Li Shuai Wang 《Journal of Biosciences and Medicines》 2024年第9期42-53,共12页
Objectives: To summarize the current status and outlook of pancreatic duct drainage in the learning curve period of laparoscopic pancreaticoduodenectomy (LPD). Methods: By searching the literature related to the effic... Objectives: To summarize the current status and outlook of pancreatic duct drainage in the learning curve period of laparoscopic pancreaticoduodenectomy (LPD). Methods: By searching the literature related to the efficacy analysis of internal versus external pancreatic duct drainage in pancreaticoduodenectomy (OPD) and the learning curve period of laparoscopic pancreaticoduodenectomy in recent years at home and abroad and making a review. Results: Because of the complexity of the LPD surgical procedure, the high technical requirements and the high complication rate, it is necessary for the operator and his/her team to carry out a certain number of cases to pass through the learning curve in order to have a basic mastery of the procedure. In recent years, more and more pancreatic surgeons have begun to promote and use pancreatic duct drains. However, no consensus conclusion has been reached on whether to choose internal or external drainage for pancreatic duct placement and drainage in LPD. Conclusions: Intraoperative application of pancreatic duct drainage reduces the incidence of pancreatic fistula during the learning curve of laparoscopic pancreaticoduodenectomy. However, external pancreatic duct drainage and internal pancreatic duct drainage have both advantages and disadvantages, so when choosing the drainage method, one should choose the appropriate drainage method in conjunction with one’s own conditions, so as to reduce the incidence of complications. 展开更多
关键词 PANCREATICODUODENECTOMY LAPAROSCOPY Pancreatic Duct Drainage Learning curve Period
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Wind-sand flow simulation and radius optimization of highway embankment under different vertical curve radius
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作者 LI Liangying LI Qi +2 位作者 WANG Xu XIN Guowei WANG Zhenqiang 《Journal of Mountain Science》 SCIE CSCD 2024年第8期2533-2546,共14页
It is of great practical value to explore the correlation between the vertical curve radius of desert highway and the increase of sand accumulation in local lines,and to select the appropriate vertical curve radius fo... It is of great practical value to explore the correlation between the vertical curve radius of desert highway and the increase of sand accumulation in local lines,and to select the appropriate vertical curve radius for reducing the risk of sand accumulation.In this study,three-dimensional models of desert highway embankments with different vertical curve radii were constructed,and Fluent software was used to simulate the wind-sand flow field and sand accumulation distribution of vertical curve embankments.The results show that:(1)Along the direction of the road,the concave and the convex vertical curve embankments have the effect of collecting and diverging the wind-sand flow,respectively.When the radius of the concave vertical curve is 3000 m,5000 m,8000 m,10000 m and 20000 m,the wind velocity in the middle of the vertical curve is 31.76%,22.58%,10.78%,10.53%and 10.44%,higher than that at both ends.When the radius of the convex vertical curve is 6500 m,8000 m,10000 m,20000 m and 30000 m,the wind velocity at both ends of the vertical curve is 14.06%,9.99%,6.14%,3.22%and 2.41%,higher than that in the middle.The diversion effect also decreases with the increase of the radius.(2)The conductivity of the concave and convex vertical curve embankments with different radii is greater than 1,which is the sediment transport roadbed.The conductivity increases with the increase of radius and gradually tends to be stable.When the radius of the concave and convex vertical curves reaches 8000 m and 20000 m respectively,the phenomenon of sand accumulation is no longer serious.Under the same radius condition,the concave vertical curve embankment is more prone to sand accumulation than the convex one.(3)Considering the strength of the collection and diversion of the vertical curve embankment with different radii,and the sand accumulation of the vertical curve embankment in the desert section of Wuma Expressway,the radius of the concave vertical curve is not less than 8000 m,and the radius of the convex vertical curve is not less than 20000 m,which can effectively reduce the sand accumulation of the vertical curve embankment.In the desert highway area,the research results of this paper can provide reference for the design of vertical curve to ensure the safe operation of desert highway. 展开更多
关键词 Highway engineering Vertical curve Numerical simulation Embankment wind-sand flow Radius optimization
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Control and vibration analyses of a sandwich doubly curved micro-composite shell with honeycomb,truss,and corrugated cores based on the fourth-order shear deformation theory
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作者 F.SHIRDELAN M.MOHAMMADIMEHR F.BARGOZINI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第10期1773-1790,共18页
Curved shells are increasingly utilized in applied engineering due to their shared characteristics with other sandwich structures,flexibility,and attractive appearance.However,the inability of controlling and regulati... Curved shells are increasingly utilized in applied engineering due to their shared characteristics with other sandwich structures,flexibility,and attractive appearance.However,the inability of controlling and regulating vibrations and destroying them afterward is a challenge to scientists.In this paper,the curve shell equations and a linear quadratic regulator are adopted for the state feedback design to manage the structure vibrations in state space forms.A five-layer sandwich doubly curved micro-composite shell,comprising two piezoelectric layers for the sensor and actuator,is modeled by the fourth-order shear deformation theory.The core(honeycomb,truss,and corrugated)is analyzed for the bearing of transverse shear forces.The results show that the honeycomb core has a greater effect on the vibrations.When the parameters related to the core and the weight percentage of graphene increase,the frequency increases.The uniform distribution of graphene platelets results in the lowest natural frequency while the natural frequency increases.Furthermore,without taking into account the piezoelectric layers,the third-order shear deformation theory(TSDT)and fourth-order shear deformation theory(FOSDT)align closely.However,when the piezoelectric layers are incorporated,these two theories diverge significantly,with the frequencies in the FOSDT being lower than those in the TSDT. 展开更多
关键词 vibration and control doubly curved shell micro-composite HONEYCOMB TRUSS corrugate core
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Analytical Determination of Size and Location of Roadside Horizontal Sightline Offsets for Compound Curves
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作者 Timur Mauga 《Journal of Transportation Technologies》 2024年第1期119-135,共17页
AASHTO’s guideline for geometric design of highways and similar guidelines require that roadside areas on the inside of horizontal curves be cleared of high objects to provide stopping sight distance. The guidelines ... AASHTO’s guideline for geometric design of highways and similar guidelines require that roadside areas on the inside of horizontal curves be cleared of high objects to provide stopping sight distance. The guidelines have analytical models for determining the extent of clearance, known as the horizontal sightline offset or clearance offset, for simple curves. Researchers in the past have developed analytical models for clearance offsets for spiraled and reverse curves. Very few researchers developed analytical models for available sight distances for compound curves. Still missing are models for horizontal sightline offsets and locations of the offsets for compound curves. The objective of this paper is to present development of analytical models and charts for determining horizontal sightline offsets and their locations for compound curves. The paper considers curves whose component arcs are individually shorter than stopping sight distance. The resulting models and the charts have been verified with accurate values determined using graphical methods. The models and the charts will find application in geometric design of highway compound curves. 展开更多
关键词 Sight Distance Roadside Clearance Offsets Compound curves
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