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Development of an early warning model for stability evaluation of polyphenol-rich fruit juice based on multiple light scattering combined with artificial neural network
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作者 Haozhou Huang Yurou Jiang +6 位作者 Mengqi li Youde Zheng Xiaohong Chen li han Runchun Xu Dingkun Zhang Junzhi lin 《Journal of Future Foods》 2026年第6期1018-1027,共10页
The stability of fruit juice has consistently been an important concern in the food processing industry,which can be time-consuming and costly.Therefore,developing accurate stability early-warning model may serve as a... The stability of fruit juice has consistently been an important concern in the food processing industry,which can be time-consuming and costly.Therefore,developing accurate stability early-warning model may serve as a viable solution.Based on multiple light scattering technology,this paper collects the stability data as the training set of Triphala fruit juice over a three-month period and finds that the sediment amount reached 0.6 mg/mL,composed of ellagic acid and phlobaphene,with the solution's light transmittance fluctuating range(23%-76%)and the particle size(0.27-0.29μm)on day 75.The early warning model comprises a synergistic integration of long short-term memory and backpropagation neural network models.The model exhibits a mean absolute percentage error of 0.626%,an R^(2) of 0.911,and an accuracy of 85.71%.This model is capable of predicting key stability parameters,including sedimentation,transmittance,particle size,particle migration rate,and stability index,within a 90-day period in just 7 days,and thereby provide accurate early-stage stability alerts. 展开更多
关键词 SEDIMENTATION Intelligent manufacturing Long short-term memory Backpropagation Triphala fruit juice
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椎旁肌脂肪浸润与退行性腰椎管狭窄症行PLIF术后植骨融合率的相关性
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作者 孙秀钦 马远 +1 位作者 李含 李森 《颈腰痛杂志》 2025年第3期444-448,共5页
目的探讨椎旁肌脂肪浸润与退行性腰椎管狭窄症行后路腰椎椎间融合术(PLIF)术后植骨融合率的相关性。方法选择2016年1月至2019年12月在本院因退行性腰椎管狭窄症行PLIF手术治疗的192例患者资料进行回顾性分析,采用Brangitan评分评估植骨... 目的探讨椎旁肌脂肪浸润与退行性腰椎管狭窄症行后路腰椎椎间融合术(PLIF)术后植骨融合率的相关性。方法选择2016年1月至2019年12月在本院因退行性腰椎管狭窄症行PLIF手术治疗的192例患者资料进行回顾性分析,采用Brangitan评分评估植骨融合情况,采用MRI检测腰椎L 4-5椎间盘中心位置的双侧多裂肌、竖脊肌的相对总横截面积(rTCSA)和脂肪浸润情况,以及腰大肌相对功能横截面积(rFCSA),根据患者椎间植骨融合情况分为不融合组和融合组,比较两组患者多裂肌、竖脊肌、腰大肌的MRI参数;采用Logistic回归分析剔除混杂因素的影响,分析椎旁肌退变指标与患者术后椎间植骨不融合的相关性。结果不融合组患者的多裂肌和竖脊肌脂肪浸润程度均高于融合组,差异均有统计学意义(P<0.05)。不融合组患者多裂肌rTCSA低于融合组,差异有统计学意义(P<0.05);两组患者的竖脊肌rTCSA和腰大肌rFCSA差异均无统计学意义(P>0.05)。剔除混杂因素影响后,多裂肌rTCSA和竖脊肌椎旁脂肪浸润不是影响PLIF术后椎间植骨不融合的因素(P>0.05),多裂肌脂肪浸润是PLIF术后椎间植骨不融合的风险因素(P<0.05)。结论多裂肌脂肪浸润可影响PLIF术后植骨融合,术前应评估患者的多裂肌脂肪浸润情况。 展开更多
关键词 后路腰椎椎间融合术 腰椎管狭窄 椎旁肌 脂肪浸润 退行性疾病 植骨融合
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Effect of the Retarder on Initial Hydration and Mechanical Properties of the"one-step"Alkaliactivated Composite Cementitious Materials 被引量:1
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作者 DING Rui HE Yue +3 位作者 li Xingchen li han TIAN Hao WANG Hongen 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第5期1199-1213,共15页
This paper studied the effects of different retarders on the performance of the"one-step"alkali-activated composite cementitious material(ACCM)which is composed of ground granulated blast slag(GGBS)and fly a... This paper studied the effects of different retarders on the performance of the"one-step"alkali-activated composite cementitious material(ACCM)which is composed of ground granulated blast slag(GGBS)and fly ash(FA),and analyzed its mechanical properties,hydration mechanism,and retardation mechanism.The effects of retarders on the hydration products,mechanical properties,and hydration kinetics of ACCM were investigated using XRD,SEM,FTIR,EDS,and thermoactive microcalorimetry.The results showed that Na_(2)B_(4)O_(7)·10H_(2)O(B)delayed the exotherm during the alkali activation process and could effectively delay the setting time of ACCM,but the mechanical properties were slightly decreased.The setting time of ACCM increased with the increase in SG content,but the mechanical properties of ACCM decreased with the increase in SG content.C1_(2)H_(22)O_(11)(CHO)could effectively delay the hydration reaction of ACCM and weakly enhanced the compressive strength.H_(3)PO_(4)(HP)at a concentration of 0.05 mol/L had a certain effect on ACCM retardation,but HP at a concentration of 0.07 and 0.09 mol/L had an effect of promoting the setting and hardening time of ACCM. 展开更多
关键词 "one-step"alkali-activated composite cementitious materials solid activator hydration mechanism RETARDER retarding mechanism
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Regulation of mild moxibustion on non-neuronal cholinergic system in ulcerative colitis rats 被引量:1
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作者 PENG Guangbin li han +8 位作者 ZHU Lu QI Qin ZHENG Shiyu ZhanG linshan liN Yaying MA Zhe WU Luyi HUANG Yan WU Huangan 《Journal of Traditional Chinese Medicine》 2025年第2期368-375,共8页
OBJECTIVE:To investigate the effect and mechanism of mild moxibustion on the non-neuronal cholinergic system(NNCS) in rats with ulcerative colitis(UC).METHODS:UC rat model was established by administering 4% dextran s... OBJECTIVE:To investigate the effect and mechanism of mild moxibustion on the non-neuronal cholinergic system(NNCS) in rats with ulcerative colitis(UC).METHODS:UC rat model was established by administering 4% dextran sulfate sodium.After 7 d,mild moxibustion,α7 nicotinic acetylcholine receptors(α7nAchRs) antagonist(α-bungarotoxin,α-BGT),vesicular acetylcholine transport inhibitor(vesamicol hydrochloride,VH) and organic cation transporters inhibitor(quinine,Qu) treatments were performed once daily for 7 d.Haematoxylin and eosin staining was used for morphological evaluation of colon tissues.Enzymelinked immunosorbent assay(ELISA) was used to measure the protein expressions of interleukin-1β(IL-1β) and choline acetyltransferase(ChAT) in colon tissue.Reverse transcription quantitative real-time polymerase chain reaction(RT-q PCR) was used to detect the mRNA expressions of IL-1β,carnosine acetyltransferase(CarAT),ChAT,and nuclear factor kappa-B p65 subunit(NF-κB p65) in colon tissue.Western blot was used to detect NF-κB p65 protein expression in colon tissue.Immunofluorescence was used to detect the expressions of neuronal acetylcholine(nAch) and non-neuronal acetylcholine(nnAch,released by NNCS) in colon tissue.RESULTS:Mild moxibustion inhibited colon inflammation and repaired mucosal damage to the colon in UC rats.Meanwhile,mild moxibustion could downregulate the expressions of IL-1β,NF-κB p65 protein and mRNA(P < 0.01),and upregulate the expressions of ChAT protein and CarAT mRNA(P < 0.05,P < 0.01).The α7nAChR antagonist α-BGT can reverse the protective effect of mild moxibustion on the UC and the inhibitory effect on the inflammatory factors.VH cannot affect the effect of mild moxibustion on the expressions of IL-1β and nnAch,while Qu can reverse the effect of mild moxibustion on the expression of IL-1β and nnAch.CONCLUSIONS:Mild moxibustion can inhibite colon inflammation in UC rats,which is closely related to the release of acetylcholine by NNCS and its mediated mechanism of cholinergic anti-inflammation pathway. 展开更多
关键词 colitis ulcerative non-neuronal cholinergic system NEUROIMMUNOMODULATION mild moxibustion
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基于Web of Science的深静脉血栓病人生活质量研究现状、热点和发展趋势
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作者 李涵 李婷 王晓琴 《循证护理》 2026年第5期1026-1034,共9页
目的:分析深静脉血栓病人生活质量的研究现状、热点和发展趋势。方法:检索Web of Science核心合集数据库中科学引文索引扩展版和社会科学引文索引建库至2024年收录的深静脉血栓病人生活质量的相关文献,利用VOSviewer软件对发文作者、期... 目的:分析深静脉血栓病人生活质量的研究现状、热点和发展趋势。方法:检索Web of Science核心合集数据库中科学引文索引扩展版和社会科学引文索引建库至2024年收录的深静脉血栓病人生活质量的相关文献,利用VOSviewer软件对发文作者、期刊、国家、文献共被引分析、作者共被引及关键词共现进行可视化分析,采用CiteSpace软件,基于对数似然率(LLR)算法开展文献共被引聚类及关键词突现分析。结果:共纳入304篇文献,涉及40个国家的1 391名作者,该领域的发文量呈上升趋势;美国的发文量居全球首位;高产学者主要来自加拿大和美国;发文量排名居前2位的期刊为Thrombosis Research和Phlebology;研究热点包括深静脉血栓病人的症状管理及风险因素、生活质量与心理健康的关系、不同治疗干预及结果对生活质量的影响,长期并发症(如血栓后综合征)的管理及其经济负担、深静脉血栓管理指南及预测因素;研究趋势包括深静脉血栓病人生活质量评估工具的验证、导管定向性溶栓治疗(CaVenT)对深静脉血栓病人生活质量的影响、深静脉血栓疾病的严重程度与生活质量的关联等。结论:深静脉血栓病人生活质量的研究处于发展阶段,国外已形成核心作者群,研究成果和方法备受关注,我国学者可学习借鉴国外的研究经验和方法,加强这一领域的研究,促进我国在深静脉血栓病人生活质量方面的进步与发展。 展开更多
关键词 深静脉血栓 生活质量 现状 热点 发展趋势 文献计量学
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传统酸面团中微生物种类及其对发酵馒头风味特性影响的研究进展
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作者 陈迪 徐言平 +2 位作者 白良琛 李涵 郭帅涛 《河南工业大学学报(自然科学版)》 北大核心 2026年第1期121-129,共9页
传统酸面团作为一种天然发酵剂,其微生物群落与产品风味特性是决定发酵面制品品质的核心要素。酸面团中的主要微生物(乳酸菌和酵母菌)通过代谢产生醇类、醛类、酯类、酮类、酸类和酚类等风味物质,从而决定了酸面团及其发酵馒头的主要风... 传统酸面团作为一种天然发酵剂,其微生物群落与产品风味特性是决定发酵面制品品质的核心要素。酸面团中的主要微生物(乳酸菌和酵母菌)通过代谢产生醇类、醛类、酯类、酮类、酸类和酚类等风味物质,从而决定了酸面团及其发酵馒头的主要风味特性。综述了传统酸面团中的主要微生物、酸面团发酵馒头中的风味物质,以及微生物与风味物质之间的关系,并对未来研究方向进行了展望,旨在为研究风味物质的种类及生成途径提供参考,为精准改善酸面团馒头风味奠定基础。 展开更多
关键词 酸面团 微生物种类 风味特性
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PU基体和吸波材料热带海洋大气环境下力学性能变化规律研究
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作者 罗丹 吴欣睿 +5 位作者 任宏宇 李昊瑜 李旭 彭冬 李晗 李鸿飞 《环境技术》 2026年第1期18-22,共5页
为研究PU基体和吸波材料在热带海洋大气环境下的力学性能变化规律。在某试验站采用黑箱暴露贮存方式开展1年的暴露贮存试验,分别通过拉伸强度与断裂伸长率研究其力学性能变化规律。PU基体和吸波材料在1年的黑箱暴露贮存试验下,其力学性... 为研究PU基体和吸波材料在热带海洋大气环境下的力学性能变化规律。在某试验站采用黑箱暴露贮存方式开展1年的暴露贮存试验,分别通过拉伸强度与断裂伸长率研究其力学性能变化规律。PU基体和吸波材料在1年的黑箱暴露贮存试验下,其力学性能呈总体下降趋势,并在贮存1年左右就发生了明显的粉化现象。而吸波材料的防水覆膜对材料具有明显的保护作用,大大降低了对空气中水汽的敏感性。吸波材料在热带海洋大气环境下的力学性能优于PU基体。 展开更多
关键词 PU基体 吸波材料 热带海洋大气环境 力学性能变化规律
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Multiloc髓内钉与Phlios钢板在中老年肱骨近端骨折中的应用效果比较 被引量:10
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作者 吴冯胜 徐执扬 +4 位作者 李晗 吴飞华 苏新杰 梁喜斌 陈蕾 《中国医刊》 CAS 2021年第7期738-741,共4页
目的探讨Multiloc髓内钉对中老年肱骨近端骨折的临床治疗效果。方法回顾性分析2017年1月至2020年1月北京市垂杨柳医院收治的58例中老年肱骨近端骨折患者的临床资料,根据手术方式的不同分为对照组(采用Phlios钢板内固定治疗,24例)和观察... 目的探讨Multiloc髓内钉对中老年肱骨近端骨折的临床治疗效果。方法回顾性分析2017年1月至2020年1月北京市垂杨柳医院收治的58例中老年肱骨近端骨折患者的临床资料,根据手术方式的不同分为对照组(采用Phlios钢板内固定治疗,24例)和观察组(采用Multiloc髓内钉内固定治疗,34例)。比较两组的手术时间、术中出血量、住院时间及并发症发生情况,采用疼痛视觉模拟量表(visual analogue scale,VAS)评分、日本骨科协会评估治疗(Japanese Orthopaedic Association scores,JOA)评分及Oswestry功能障碍指数(Oswestry disability index,ODI)评价两组的临床疗效,采用简明肩关节功能测试(simple shoulder test,SST)及欧洲肩关节协会Constant评分系统评价肩关节功能。结果观察组的手术时间、术中出血量、住院时间均明显低于对照组,差异有显著性(P<0.05)。两组并发症发生率比较差异无显著性(P>0.05)。末次随访时,观察组患者的VAS、JOA及ODI评分均明显低于对照组,肩关节功能SST评分及Constant评分均明显高于对照组,差异有显著性(P<0.05)。结论中老年肱骨近端骨折采用Multiloc髓内钉内固定治疗可有效提升手术效果,改善肩关节功能,并能简化手术操作,减少不良事件的发生。 展开更多
关键词 髓内钉 Phlios钢板 肱骨近端骨折 临床疗效
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Pd/Cu-cocatalyzed multi-site functionalization of in-situ generated alkenes toward carbazole-based aggregation-induced emission luminogens
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作者 Meiqi Zhang Xueyuan Yan +8 位作者 Zheng liu Hongyuan Bai Hongwei Ma Genping Huang Bo Zhang Dezhu Xu Wenjia han li han Tenglong Guo 《Chinese Journal of Catalysis》 2025年第2期176-184,共9页
In contrast to the predominant mono or difunctionalization of alkenes,the multi-site functionalization of alkenes involving the synergistic formation of more than two new C–C or C–X bonds is much challenging,especia... In contrast to the predominant mono or difunctionalization of alkenes,the multi-site functionalization of alkenes involving the synergistic formation of more than two new C–C or C–X bonds is much challenging,especially for developing new reaction pathway to afford the functional heterocycle compounds with aggregation-induced emission(AIE)property has been rarely reported.In present work,the multi-site functionalization of in situ generated alkenes with indoles has been developed for the synthesis of diversely functionalized carbazoles through the synergistic construction of multiple C–C bonds and C=O bond.A proposed reaction sequence involving C–H alkenylation/radical oxygen atom transfer/Diels-Alder cycloaddition/dehydrogenative aromatization was supported by experiments and density functional theory calculations.Further derivative carbazole-linked-quinoxaline skeletons represent a class of AIEgens with acceptor-donor-acceptor configuration,which generated the desired twisted intramolecular charge transfer(TICT)AIE properties and could be used as fluorescent probes for detecting the micrometer-sized phase separation of polymer blends.The protocol provides a concise route for the synthesis and application of carbazole-based AIE luminogens. 展开更多
关键词 Multi-site functionalization CARBAZOLES Aggregation-induced emission luminogens Radical oxygen atom transfer Microphase separation
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Effective pure qP-wave equation and its numerical implementation in the time-space domain for 3D complicated anisotropic media
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作者 Shi-Gang Xu Xing-Guo Huang li han 《Petroleum Science》 2025年第4期1534-1547,共14页
Seismic anisotropy has been extensively acknowledged as a crucial element that influences the wave propagation characteristic during wavefield simulation,inversion and imaging.Transversely isotropy(TI)and orthorhombic... Seismic anisotropy has been extensively acknowledged as a crucial element that influences the wave propagation characteristic during wavefield simulation,inversion and imaging.Transversely isotropy(TI)and orthorhombic anisotropy(OA)are two typical categories of anisotropic media in exploration geophysics.In comparison of the elastic wave equations in both TI and OA media,pseudo-acoustic wave equations(PWEs)based on the acoustic assumption can markedly reduce computational cost and complexity.However,the presently available PWEs may experience SV-wave contamination and instability when anisotropic parameters cannot satisfy the approximated condition.Exploiting pure-mode wave equations can effectively resolve the above-mentioned issues and generate pure P-wave events without any artifacts.To further improve the computational accuracy and efficiency,we develop two novel pure qP-wave equations(PPEs)and illustrate the corresponding numerical solutions in the timespace domain for 3D tilted TI(TTI)and tilted OA(TOA)media.First,the rational polynomials are adopted to estimate the exact pure qP-wave dispersion relations,which contain complicated pseudo-differential operators with irrational forms.The polynomial coefficients are produced by applying a linear optimization algorithm to minimize the objective function difference between the expansion formula and the exact one.Then,the developed optimized PPEs are efficiently implemented using the finite-difference(FD)method in the time-space domain by introducing a scalar operator,which can help avoid the problem of spectral-based algorithms and other calculation burdens.Structures of the new equations are concise and corresponding implementation processes are straightforward.Phase velocity analyses indicate that our proposed optimized equations can lead to reliable approximation results.3D synthetic examples demonstrate that our proposed FD-based PPEs can produce accurate and stable P-wave responses,and effectively describe the wavefield features in complicated TTI and TOA media. 展开更多
关键词 Anisotropic media Wavefield extrapolation Pure qP-wave equation Optimization algorithm Finite-difference method Time-space domain
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Cooperative Iteration Matching Method for Aligning Samples from Heterogeneous Industrial Datasets
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作者 li han SHI Guohong +1 位作者 liU Zhao ZHU Ping 《Journal of Shanghai Jiaotong university(Science)》 2025年第2期375-384,共10页
Industrial data mining usually deals with data from different sources.These heterogeneous datasets describe the same object in different views.However,samples from some of the datasets may be lost.Then the remaining s... Industrial data mining usually deals with data from different sources.These heterogeneous datasets describe the same object in different views.However,samples from some of the datasets may be lost.Then the remaining samples do not correspond one-to-one correctly.Mismatched datasets caused by missing samples make the industrial data unavailable for further machine learning.In order to align the mismatched samples,this article presents a cooperative iteration matching method(CIMM)based on the modified dynamic time warping(DTW).The proposed method regards the sequentially accumulated industrial data as the time series.Mismatched samples are aligned by the DTW.In addition,dynamic constraints are applied to the warping distance of the DTW process to make the alignment more efficient.Then a series of models are trained with the cumulated samples iteratively.Several groups of numerical experiments on different missing patterns and missing locations are designed and analyzed to prove the effectiveness and the applicability of the proposed method. 展开更多
关键词 dynamic time warping mismatched samples sample alignment industrial data data missing
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Research on the Ice Resistance and Propulsion Performance of Polar Ships via the CFD-DEM Coupling Method
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作者 ZHENG Si-jie SONG Bo-yang +5 位作者 ZHOU li HUANG Qiao-gao XIE Chang li han HE Guang-wei liNG Hong-jie 《China Ocean Engineering》 2025年第2期232-243,共12页
Polar marine equipment plays an important role in Arctic engineering,especially in the development of polar ships and ice-class propellers.When polar ships navigate in brash ice channels,the brash ice not only increas... Polar marine equipment plays an important role in Arctic engineering,especially in the development of polar ships and ice-class propellers.When polar ships navigate in brash ice channels,the brash ice not only increases resistance but also has adverse effects on their propulsion performance.On the basis of coupled computational fluid dynamics(CFD)and the discrete element method(DEM),this paper aims to numerically investigate the resistance and propulsion performance of a polar in a brash ice channel while considering the rotation status of the propeller by both experimental and numerical methods.Both ship resistance and ice motion under Froude numbers of 0.0557,0.0696,0.0836,0.975,and 0.1114 are studied when the propeller does not rotate.The influences of the rotating propeller on the ice brash resistance and flow are discussed.The thrust due to the propeller and ice resistance in the equilibrium state are also predicted.The errors between the thrust and total resistance are approximately 1.0%,and the maximum error between the simulated and predicted total resistance is 3.7%,which validates the CFD-DEM coupling method quite well.This work could provide a theoretical basis for the initial design of polar ships with low ice class notation and assist in planning navigation for merchant polar ships in brash ice fields. 展开更多
关键词 polar ships propeller CFD-DEM ice resistance propulsion performance
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基于改进的Hessian和Live-wire算法的岩石节理裂隙检测 被引量:3
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作者 王艳 李晗 +5 位作者 陈佳悦 陈卫卫 王梦菲 闫迪 李宏霞 王卫星 《金属矿山》 CAS 北大核心 2023年第8期265-271,共7页
在图像处理中,由于岩石节理裂隙是最复杂的线状目标之一,针对该对象的检测算法的研究一直是一个难题。故此,研究了一种新的跟踪裂隙边缘线的算法。首先,若图像尺寸太大,进行有选择的图像缩小,然后采用基于Geodesic Shadow Removal的算... 在图像处理中,由于岩石节理裂隙是最复杂的线状目标之一,针对该对象的检测算法的研究一直是一个难题。故此,研究了一种新的跟踪裂隙边缘线的算法。首先,若图像尺寸太大,进行有选择的图像缩小,然后采用基于Geodesic Shadow Removal的算法进行图像平滑,再用一种基于Hessian矩阵算法增强模糊及微细节理裂隙;用一种基于Live-wire Contour思想的节理裂隙边缘线特征点提取的算法进行边缘特征点提取;最后基于特征点之间的距离及相应线段夹角来连接特征点以形成完整的线段。选择了200幅图像进行实验,通过与十多种传统和新近的算法相比,新算法能够在复杂的岩石节理裂隙图像中,准确快速地提取节理裂隙边缘线,为在该领域引进深度学习等方法奠定基础。 展开更多
关键词 岩石节理裂隙 Live-wire Geodesic shadow HESSIAN
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Mechanisms and Pathways for the Cultural Tourism Industry to Empower Integrated Urban-Rural Development in the Digital Era
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作者 Zhou Jin Cao Yang li han 《Contemporary Social Sciences》 2025年第3期63-82,共20页
Integrated urban-rural development is a crucial stage in the development of China’s urban-rural relations and is essential for Chinese modernization.In the digital era,the cultural tourism industry has the potential ... Integrated urban-rural development is a crucial stage in the development of China’s urban-rural relations and is essential for Chinese modernization.In the digital era,the cultural tourism industry has the potential to promote integrated urban-rural development through multidimensional integration mechanisms,including cultural exchanges,resource sharing,and industrial linkages.Specifically,by innovating cultural tourism development models,the efficiency of labor allocation between urban and rural areas can be improved,fostering the transformation of rural cultural tourism and its related industries.By expanding the cultural tourism scenarios,new spaces for rural cultural consumption can be constructed,which would help to reduce urban and rural consumption disparities.By establishing cultural tourism development platforms and facilitating the sharing of data elements,the coordinated development of urban and rural public cultural services can be promoted,which would reduce the service gaps between urban and rural areas.By leveraging smart city construction to drive the development of the rural digital infrastructure,integrated urban-rural development,guided by a“digital+”approach,can then be fostered and help to reduce urban and rural development gaps.Building on this foundation,the digital transformation of cultural tourism will advance industrial linkages,resource sharing,factor mobility,and spatial co-creation within urban and rural cultural tourism,gradually realizing integrated urban-rural development and ultimately driving rural revitalization and fostering common prosperity. 展开更多
关键词 digital era cultural tourism urban-rural integration rural revitalization
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Influence of Steel Slag Content on the Characteristics of"One-step"Alkali-activated Composite Cementitious Materials
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作者 DING Rui li han +3 位作者 TIAN Hao WANG Hongen CHEN Yuqi li Wenfu 《Journal of Wuhan University of Technology(Materials Science)》 2025年第4期1105-1112,共8页
A solid,fast-dissolving sodium silicate was used as an alkaline activator.Granulated blast furnace slag(GGBS),metakaolin(MK),and steel slag(SS)were used as the cementious components to prepare a ternary composite ceme... A solid,fast-dissolving sodium silicate was used as an alkaline activator.Granulated blast furnace slag(GGBS),metakaolin(MK),and steel slag(SS)were used as the cementious components to prepare a ternary composite cementitious material known as alkali-activated steel slag composite cementitious material(ASCM)by the"one-step method".The impacts of cementitious components,alkali activator modulus,and Na_(2)O%on the mechanical strength were investigated,and the hydration products and hydration kinetics of ASCM were analyzed.The experimental results reveal that XRD,FTIR,SEM,EDS,and exothermic heat of hydration show that when GGBS:MK:SS=60wt%:10wt%:30wt%,the activator modulus is 1.2,and the alkali content is 5.5wt%,the 28 d flexural strength of ASCM mortar is 12.6 MPa,and the compressive strength is 53.3 MPa,the hydration products consist of C-S-H gel/C-A-S-H gel,mullite(3Al_(2)O_(3)-2SiO_(2)),calcite(CaCO_(3)),quartz,etc.ASCM has a large initial hydration exotherm rate but a small cumulative exotherm. 展开更多
关键词 solid activator "one-step"alkali-activated composite cementitious materials steel slag
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Impact of the Rapid Recovery Concept on Complications and Patient Quality of Life in the Perioperative Nursing of Robot-Assisted Radical Oesophageal Cancer
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作者 Rongrong Jiang li han +3 位作者 Xiaoshan Ye Jiaqi Wu Jiahuan Weng lihui Chen 《Open Journal of Nursing》 2024年第1期1-10,共10页
Aim: This study evaluates the impact of Enhanced Recovery After Surgery (ERAS) nursing on postoperative complications and quality of life in patients undergoing robot-assisted minimally invasive esophagectomy (RAMIE).... Aim: This study evaluates the impact of Enhanced Recovery After Surgery (ERAS) nursing on postoperative complications and quality of life in patients undergoing robot-assisted minimally invasive esophagectomy (RAMIE). Methods: A total of 150 patients who underwent RAMIE from January 2020 to January 2022 at our hospital were randomly assigned to either the observation group or the control group, with 75 patients in each. The control group received standard perioperative management and nursing care, while the observation group was treated with ERAS nursing strategies. Interventions continued until discharge, and outcomes such as postoperative complications, quality of life, and nutritional status were compared between the groups. Results: The observation group exhibited a significantly lower incidence of postoperative adverse reactions compared to the control group (P ionally, all dimension scores of the Short-Form 36 Health Survey (SF-36), including the total score, were higher in the observation group (P < 0.05). Furthermore, the Nutritional Risk Screening (NRS) scores for impaired nutritional status and disease severity, along with the total NRS score, were significantly lower in the observation group compared to the control group (P Conclusion: Implementing ERAS nursing in the perioperative care of patients undergoing RAMIE is associated with reduced postoperative complications and enhanced postoperative quality of life and nutritional status. . 展开更多
关键词 Robot-Assisted Radical Esophageal Cancer Surgery Rapid Rehabilitation Surgical Nursing Perioperative Period COMPLICATIONS Quality of Life
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苯乙烯-异戊二烯/丁二烯-苯乙烯的合成、氢化及其热性能研究
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作者 李浩雨 李旭文 +8 位作者 李嵬 周轩哲 丁志杰 罗毅 马红卫 冷雪菲 王艳色 韩丽 李杨 《高分子学报》 北大核心 2026年第1期200-217,共18页
苯乙烯-异戊二烯/丁二烯-苯乙烯嵌段共聚物(SI/BS)及其氢化产物SEEPS是高附加值热塑性弹性体(TPS),但其结构与热性能的构效关系尚不明确.本工作采用阴离子溶液聚合法,通过调控单体投料比与加料方式(逐步/一步)合成了一系列SI/BS,并进一... 苯乙烯-异戊二烯/丁二烯-苯乙烯嵌段共聚物(SI/BS)及其氢化产物SEEPS是高附加值热塑性弹性体(TPS),但其结构与热性能的构效关系尚不明确.本工作采用阴离子溶液聚合法,通过调控单体投料比与加料方式(逐步/一步)合成了一系列SI/BS,并进一步氢化得到不同加氢度(HD)的SEEPS.研究发现,组成与数均分子量(Mn)对玻璃化转变温度(T_(g))和分解温度(T_(d))影响不显著,但T_(g)在一定程度上受Bd含量微调.进一步考察了M_(n)、组成、HD及加料方式对SEEPS热性能(T_(g)、T_(m)、T_(c)、T_(d))的影响.发现当HD低于60%时,氢化可显著提升热性能;高于60%后,热性能变化不大.当HD高于95%时,T_(g)与T_(d)对Mn和组成的变化不敏感,但结晶温度(T_(c))和熔融温度(T_(m))随Bd含量增加而明显升高,且逐步加料法制备的SEEPS具有更高的T_(c)和T_(m).结合^(13)C-NMR及Bd/Ip共聚动力学分析推测,加料方式通过调控Bd与Ip的单体序列分布,进而影响了氢化后SEEPS的链段结构. 展开更多
关键词 热塑性弹性体 苯乙烯-异戊二烯/丁二烯-苯乙烯嵌段共聚物 热性能
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复合材料导管对泵喷推进器水动力性能及振动特性的影响
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作者 张梦正 李鑫明 +3 位作者 李晗 黄桥高 秦登辉 沈克纯 《中国舰船研究》 北大核心 2026年第1期167-176,共10页
[目的]针对泵喷推进器的轻量化与减振需求,提出将碳纤维增强复合材料(CFRC)应用于泵喷推进器导管。[方法]首先,建立泵喷推进器CFD/FEM双向流固耦合数值计算方法,获取泵喷推进器在流体激励下的结构响应,进而分析结构变形对水动力性能和... [目的]针对泵喷推进器的轻量化与减振需求,提出将碳纤维增强复合材料(CFRC)应用于泵喷推进器导管。[方法]首先,建立泵喷推进器CFD/FEM双向流固耦合数值计算方法,获取泵喷推进器在流体激励下的结构响应,进而分析结构变形对水动力性能和轴系激励的影响;然后,建立泵喷推进器的CFRC导管模型,分析CFRC对泵喷推进器水动力、结构振动传递和响应的影响。[结果]CFRC导管泵喷推进器的结构变形为10^(−7)m量级,对水动力性能没有影响;复合材料导管前4阶湿模态的固有频率比干模态减少了65.3%~80.2%;在振动特性方面,在定子与导管连接约束处激励时,CFRC导管的总加速度级相较于金属材料(铜合金)下降了1.0533 dB,但在内表面激励时CFRC导管的振动性能则有所反弹。[结论]CFRC在实现轻量化的同时,还可以显著改善泵喷推进器的振动特性,研究成果可为推进器设计提供参考。 展开更多
关键词 泵喷推进器 碳纤维增强复合材料导管 水动力性能 振动特性 干湿模态 流固耦合
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鄂尔多斯盆地西缘冲断带石炭系羊虎沟组煤岩储层特征
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作者 蔺嘉昊 时保宏 +2 位作者 张雷 李涵 罗京 《西安石油大学学报(自然科学版)》 北大核心 2026年第1期1-10,29,共11页
为了探明鄂尔多斯盆地西缘祁连海域石炭系羊虎沟组煤系地层储层特征,选取西缘北段R18、E103井羊虎沟组煤岩作为研究对象,基于扫描电镜、高压压汞、气体吸附、覆压渗透率等测试方法,对羊虎沟组煤岩类型、煤质特征、孔隙结构等开展了研究... 为了探明鄂尔多斯盆地西缘祁连海域石炭系羊虎沟组煤系地层储层特征,选取西缘北段R18、E103井羊虎沟组煤岩作为研究对象,基于扫描电镜、高压压汞、气体吸附、覆压渗透率等测试方法,对羊虎沟组煤岩类型、煤质特征、孔隙结构等开展了研究,并预测优选了现实有利目标区。结果表明:①石炭系羊虎沟组沉积期处于低能稳定的潮坪-泻湖沉积体系,煤层较发育,分布较稳定,总厚度一般6~30 m;②羊虎沟组煤岩类型以光亮煤和半亮煤为主,大部分地区达到中高煤阶演化程度,煤质具有高固定碳、中高灰分、低水分和低挥发分的典型特征;③羊虎沟组煤岩孔隙类型以粒间孔、晶间孔、溶蚀孔和气孔为主,发育微裂隙,形态上呈微孔+宏孔双峰“U”形结构分布特征;④盆地西缘中段韦州-石沟驿向斜区是羊虎沟组煤岩气勘探的目标区,面积约1760 km^(2),评价有利区资源量2319×10^(8)m^(3)。该研究为鄂尔多斯盆地西缘煤岩气的勘探提供了一定的地质依据。 展开更多
关键词 储层特征 深层煤岩 煤岩气 羊虎沟组 石炭系 鄂尔多斯盆地
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基于风-桥-车-人耦合振动的公路悬索桥竖弯涡激振动条件下驾驶员晕动症研究
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作者 李涵 朱金 +1 位作者 李永乐 高宗余 《振动工程学报》 北大核心 2026年第1期279-290,共12页
为了分析大跨度公路悬索桥发生竖弯涡振时桥上驾驶员的晕动症情况,将一维竖向人体振动模型引入传统的风-车-桥耦合振动模型中,同时采用简谐涡激力模型模拟桥梁的涡振,建立大跨度桥梁涡振条件下的风-桥-车-人耦合振动分析模型,以此计算... 为了分析大跨度公路悬索桥发生竖弯涡振时桥上驾驶员的晕动症情况,将一维竖向人体振动模型引入传统的风-车-桥耦合振动模型中,同时采用简谐涡激力模型模拟桥梁的涡振,建立大跨度桥梁涡振条件下的风-桥-车-人耦合振动分析模型,以此计算人体振动响应。根据国际标准评价法ISO 2631-1:1997(E),提出以人体振动响应为基础的驾驶员晕动症指标计算方法。上述精细化算法所需的计算资源和时间较多,而为了便于实际的工程应用,还提出了一种快速计算驾驶员人体振动响应和晕动症指标的简化算法。基于风-桥-车-人耦合振动模型,以一座大跨度悬索桥为例,分析涡振条件下桥上车辆及驾驶员人体各部位的振动响应。同时,将采用精细化算法和简化算法计算得到的涡振条件下桥上驾驶员的人体振动响应及晕动症指标进行了对比,以验证简化算法的可行性。研究结果表明:在桥梁涡振的激励下,人-车耦合振动效应对车辆自身的振动几乎没有影响;人体与车体以及人体各个部位的振动响应差异随着涡振频率的增加而增加;简化算法的计算效率较高,且对于实际工程而言具有可行性。 展开更多
关键词 桥梁工程 涡激振动 风-桥-车-人耦合振动 晕动症 人体振动模型
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