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基于耦合神经网络反应扩散模型的图像增强方法研究

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现代计算机 2024年第10期30卷 55-59,64页

作者：周嵩松李平赵文博王行建东北林业大学计算机与控制工程学院哈尔滨150040

随着人工智能技术的迅速发展,图像处理已经广泛应用于交通、医疗、农林、航空航天等领域,并且对图像质量要求也越来越高。针对图像增强问题,提出了一种利用神经网络模型,将FitzHugh-Nagumo反应扩散模型转变为微分动力系统的方法,来改进... 详细信息

随着人工智能技术的迅速发展,图像处理已经广泛应用于交通、医疗、农林、航空航天等领域,并且对图像质量要求也越来越高。针对图像增强问题,提出了一种利用神经网络模型,将FitzHugh-Nagumo反应扩散模型转变为微分动力系统的方法,来改进耦合神经网络,引入自适应的阈值,得到耦合神经元的非线性动力学模型,利用此模型可使图像对比度得到提升,起到增强图像的效果。该模型的适用面更广,图像对比度拉伸效果更好,视觉增强效果更为明显。

关键词：耦合神经网络反应扩散模型 FitzHugh-Nagumo 图像增强

The measurement of internal surface characteristics of fuel nozzle orifices using the synchrotron X-ray micro CT technology

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Science China(Technological Sciences) 2018年第11期61卷 1621-1627页

作者： LI ZhiLong zhao wenbo WU ZhiJun GONG HuiFeng HU ZongJie DENG Jun LI LiGuang School of Automotive Studies Tongji University

The design of fuel nozzle orifices at micrometer scales is crucial for generating desired fuel spray patterns, and consequently optimizing fuel combustion and emission in internal combustion engines. Although there have been several recent advancements in the characterization of orifice internal geometries, quantitative studies on the orifice internal wall surface characteristics are still challeges due to the lack of effective measuring methods. A new method for quantifying the internal wall surface characteristics of fuel nozzle micro-orifices is presented in this study to achieve a better understanding and prediction of spray characteristics: Firstly, by using the synchrotron X-ray micro CT technology, a three-dimensional digital model of the fuel nozzle tip was constructed. Secondly, a data post-processing technique was then applied to unfold the orifice internal wall surface to a flat base plane. Finally, the conventional surface characteristic quantification techniques can be used to evaluate the wall surface characteristics. Two diesel nozzles with identical orifice geometry design but different hydraulic grinding time were measured using this method. One nozzle was hydro-ground for 2 s while the other was not. The internal wall surfaces of the two orifices were successfully unfolded to base planes and their surface characteristics were respectively analyzed. The surface fluctuation data were perfectly reproduced by a Gaussian distribution function. The standard deviations of the distribution demonstrate the fluctuation range and the distribution of the entire surface fluctuation profiles. As an effective parameter to evaluate the hydraulic grinding process and the spray behaviors, the standard deviation was considered feasible for the analysis of the orifice internal wall surface characteristics.

关键词： automotive fuel spray nozzle orifice wall surface characteristics synchrotron X-ray micro CT

Simulation and experimental verification of the dependence of collection efficiency on the shape of a dual micropipette

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Science China Chemistry 2011年第8期54卷 1311-1318页

作者： GAO zhao LI Bo zhao wenbo CHEN Yong HU Mo LIANG ZhongWei ZHOU ShuLin SHAO YuanHua College of Chemistry and Molecular Engineering Peking University Beijing 100871 China School of Mathematical Sciences Peking University Beijing 100871 China Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China

The current responses of a generation/collection (G/C) system based on dual micropipettes are simulated by the boundary element (BE) method, from which the collection efficiencies for various pipettes with different geometries are calculated. The influence of the shape of a dual micropipette on the collection efficiency, such as curvature and symmetry of the pipette, as well as the thickness of glassy band between generator and collector, is presented and discussed in detail. Moreover, the simulation results have been tested using the experiments of potassium and sodium ions transfers facilitated by dibenzo-18-crown-6 (DB18C6) at the water/1,2-dichloroethane (W/DCE) interface. These results demonstrate that the BE method is an efficient and useful approach for the simulation of collection efficiency of symmetric geometries of dual micropipettes operating in the G/C mode under transport conditions of diffusion control. However, there are still some problems for the cases of asymmetric dual micropipettes, which show rather large differences between the values of simulated and experimental ones. This work also indicates that such an ionic G/C technique should have advantages in applications when the dual pipettes have symmetric geometries.

关键词： boundary element method dual micropipettes collection efficiency simulation

不同负压封闭引流压力与大鼠创面中厚皮片移植疗效的关系研究

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系统医学 2024年第15期9卷 5-9页

作者：黄志明李自军骆丽赵俊延赵文波遵义医科大学第五附属(珠海)医院骨一科广东珠海519110

目的研讨不同负压封闭引流压力与大鼠创面中厚皮片移植疗效的关系。方法目的选取2022年8月—2023年10月遵义医科大学第五附属(珠海)医院实验室购买的48只实验大鼠,均行创面中厚皮片移植术,根据负压值大小及治疗方案分为低负压组(负压... 详细信息

目的研讨不同负压封闭引流压力与大鼠创面中厚皮片移植疗效的关系。方法目的选取2022年8月—2023年10月遵义医科大学第五附属(珠海)医院实验室购买的48只实验大鼠,均行创面中厚皮片移植术,根据负压值大小及治疗方案分为低负压组(负压值75 mmHg)、中负压组(负压值125 mmHg)、高负压组(负压值175 mmHg)及打包加压组,比较组间移植疗效。结果术后7、14 d中负压组皮片存活率均高于低负压组、高负压组和打包加压组,差异有统计学意义(P均<0.05)。中负压组并发症总发生率0,低于低负压组、高负压组、打包加压组的16.70%(2/12)、33.30%(4/12)、50.00%(6/12),差异有统计学意义(χ^(2)=8.889,P<0.05)。术后7、14 d中负压组微血管密度水平均高于低负压组、高负压组和打包加压组,差异有统计学意义(P均<0.05)。术后7、14 d中负压组血管内皮生长因子、碱性成纤维细胞生长因子蛋白表达水平均高于低负压组、高负压组和打包加压组,差异有统计学意义(P均<0.05)。结论大鼠创面中厚皮片移植最佳的负压封闭引流压力为125 mmHg,能提高皮片存活率,促进VEGF、bFGF等生长因子表达,降低并发症发生率。

关键词：中厚皮片移植创面负压封闭引流不同负压大鼠

Ultrathin wavy nanowires of high-entropy alloy as cocktail solution in methanol oxidation reaction

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Progress in Natural Science:Materials International 2023年第2期33卷 225-231页

作者： Songyuan Yuan Xiran Zhu Hui Li Zheng Hu Qianqian Ren wenbo zhao Xiangyang Tang Shi Hu Department of Chemistry School of Science Tianjin Key Laboratory of Molecular Optoelectronic Science Tianjin University Institute of Energy Hefei Comprehensive National Science Center

High entropy alloys(HEAs) with adjustable composition and diverse surface active sites show good catalytic performance of methanol oxidation reaction(MOR). However, the synthesis and morphology control of HEA remains a challenge. Herein, we use a fast co-reduction method to synthesize a series of ultrathin wavy nanowires(WNWs) with an average diameter of 3–5 nm, including Pt-based and Pd-based binary alloys, and HEA with different pairs of immiscible elements. The catalytic properties of Pt Pd Ag Cu Ni WNWs show that the mass activity and stability of Pt Pd Ag Cu Ni WNWs is higher than Pt and Pd WNWs. Meanwhile we explored the cocktail effect among high entropy alloy elements through annealing. The cocktail effect among the metal elements in Pt Pd Ag Cu Ni WNWs provided more active sites with increased metal-metal interactions, thus improving the catalytic efficiency.

关键词： High-entropy alloy Co-reduction Cocktail effect Methanol oxidation reaction

电子商务专业课程思政链建设探索——以哈尔滨工程大学为例

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物流科技 2024年第17期47卷 181-184页

作者：姜金贵潘霞薛鹏赵文波哈尔滨工程大学经济管理学院黑龙江哈尔滨150001

随着高等学校课程思政建设的深入开展,课程思政建设理念正在逐步向课程链视域转换,为此,文章对电子商务专业课程思政链建设进行了探索。以哈尔滨工程大学为例,构建涵盖专业基础课程、专业核心课程、创新创业综合实践课程的电子商务专业... 详细信息

随着高等学校课程思政建设的深入开展,课程思政建设理念正在逐步向课程链视域转换,为此,文章对电子商务专业课程思政链建设进行了探索。以哈尔滨工程大学为例,构建涵盖专业基础课程、专业核心课程、创新创业综合实践课程的电子商务专业课程链,围绕“守正创新”的核心思政要素,确定课程思政链的育人目标、价值导向,探索电子商务专业课程思政链的思政内涵、思政元素、思政案例等内容,以期最大限度的实现课程思政链的整体立德树人的效果。

关键词：电子商务专业课程思政链课程建设

A Review of Engine Fuel Injection Studies Using Synchrotron Radiation X-ray Imaging

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Automotive Innovation 2019年第2期2卷 79-92页

作者： Zhijun Wu wenbo zhao Zhilong Li Jun Deng Zongjie Hu Liguang Li School of Automotive Studies Tongji UniversityShanghai 201804China

Fuel spray characteristics directly determine the formation pattern and quality of the fuel/air mixture in an engine,and thus affect the combustion *** this reason,the improvement and optimization of fuel injection systems is crucial to the development of engine *** fuel jet breakup and atomization process is a complex liquid-gas two-phase turbulent flow system that has not yet been fully *** to the limitations of standard optical measurement techniques,the spray breakup mechanism and its interaction with the nozzle internal flow are still ***,in recent years synchrotron radiation(SR)X-ray imaging technologies have been widely applied in engine fuel injection studies because of the higher energy and brilliance of third-generation SR light *** review provides a brief introduction to the development of SR technology and compares the critical parameters of the primary third-generation SR light sources available *** basic principles and applications of various X-ray imaging technologies with regard to nozzle internal structure measurements,visualization of in-nozzle flow characteristics and quantitative analyses of near-field spray transient dynamics are examined in detail.

关键词： X-ray imaging technology Fuel injection Nozzle internal structure In-nozzle flow visualization Near-field spray dynamics

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弹簧韧带损伤的研究进展

现代医药卫生 2024年第15期40卷 2657-2661页

作者：赵文博(综述) 余彬梁益建王洋(审校) 成都市第三人民医院骨科四川成都610031

弹簧韧带损伤在临床上往往容易被忽略,原因在于其发病机制较为隐匿,临床症状体征不典型。若弹簧韧带损伤得不到及时正确处理,可能导致扁平足畸形等,严重时甚至引起足部长期慢性疼痛。该文从弹簧韧带损伤的解剖和临床特征、治疗方式及术... 详细信息

弹簧韧带损伤在临床上往往容易被忽略,原因在于其发病机制较为隐匿,临床症状体征不典型。若弹簧韧带损伤得不到及时正确处理,可能导致扁平足畸形等,严重时甚至引起足部长期慢性疼痛。该文从弹簧韧带损伤的解剖和临床特征、治疗方式及术后康复等方面进行了综述。加强对弹簧韧带损伤的相关研究,降低其漏诊及误诊率,正确治疗弹簧韧带损伤及术后正规康复训练,是目前足踝外科领域研究的热点和难点。选择最佳的方式来修复损伤的弹簧韧带,以及后期制定个性化康复方案将是未来研究的重要方向。

关键词：弹簧韧带胫后肌腱内侧纵弓综述

Understanding Surface Water-Groundwater Conversion Relationship and Associated Hydrogeochemistry Evolution in the Upper Reaches of Luan River Basin, North China

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Journal of Earth Science 2024年第3期35卷 1010-1023页

作者： Le zhao Chunli Su wenbo Liu Xianjun Xie School of Environmental Studies China University of GeosciencesWuhan 430078China State Environmental Protection Key Laboratory of Source Apportionment and Control of Aquatic Pollution Ministry of Ecology and EnvironmentWuhan 430078China China Geological Environmental Monitoring Institute Beijing 100081China

Luan River is the main water source in Beijing-Tianjin-Hebei region,northern China,where the groundwater system is vulnerable and pollution issue is *** is significant for regional groundwater resources protection to identify the hydrogeochemistry evolution and affecting factors along flow direction occurred in the upper reaches,especially the surface water-groundwater(SWGW)conversion *** this study,recharge,conversion and geochemistry evolution of SW and GW were elucidated based on physical-hydrochemical indicators and stable isotopes in 36 GW samples and 20 SW samples,which were collected in July 2019 and July *** factor analysis was further utilized to determine the main factors responsible for regional hydrogeochemical *** indicate that GW recharged SW in plateau area,and SW and GW recharged each other in typical Alpine valley *** hydrochemical types are HCO3-Ca·Mg and HCO3-Ca,and the hydrochemical evolution is dominated by weathering of silicate and carbonate *** cation exchange adsorption has minor impact on groundwater *** rise of SO42-and NO3-contents in groundwater is related to industrial and agricultural *** main controlling factors of SW hydrochemical components included recharge from groundwater,industrial and mining activities,explaining 90.04%of data ***,water-rock interaction,agricultural and domestic sewage are responsible for GW quality,accounting for 83.38%.

关键词： groundwater water sources conversion relationship hydrogeochemical characteristics evolutional processes water-rock interaction factor analysis Luan River Basin.