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轴向撞击作用下内充泡沫铝薄壁铝合金腔体最优尺厚比选择

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太原学院学报（自然科学版） 2025年第1期43卷 1-8页

作者：李显辉孔德明山西工程科技职业大学建筑工程学院山西晋中030600

内充泡沫铝薄壁铝合金腔体在防撞吸能领域已经具备广泛的使用价值,但在最优截面尺寸选择方面的研究与应用较少。为进一步研究铝合金内充泡沫铝腔体最优截面尺寸,通过有限元软件ABAQUS建立了常见的方形铝合金腔体在撞击作用下的有限元模... 详细信息

内充泡沫铝薄壁铝合金腔体在防撞吸能领域已经具备广泛的使用价值,但在最优截面尺寸选择方面的研究与应用较少。为进一步研究铝合金内充泡沫铝腔体最优截面尺寸,通过有限元软件ABAQUS建立了常见的方形铝合金腔体在撞击作用下的有限元模型。结果表明:建立的有限元模型在模拟内充泡沫铝铝合金腔体抗撞击性能方面具有良好的拟合度,同时,针对现有市场中方形铝合金腔体多尺寸截面,提出尺厚比作为其截面选择参数,通过运用数值建模和非线性拟合工具,得出常见尺寸下组合截面吸能最大化的截面尺寸。研究得出的低、中、高3种撞击能量下的截面最优尺厚比可为结构防撞击装置的设计提供参考。

关键词：内充泡沫铝的薄壁铝合金管撞击试验破坏形态能量耗散最优尺厚比

Effects of dry-wet cycles on three-dimensional pore structure and permeability characteristics of granite residual soil using X-ray micro computed tomography

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第3期14卷 851-860页

作者： Ran An lingwei kong Xianwei Zhang Chengsheng li College of Urban Construction Wuhan University of Science and TechnologyWuhan430065China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu610059China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China

Due to seasonal climate alterations,the microstructure and permeability of granite residual soil are easily affected by multiple dry-wet *** X-ray micro computed tomography(micro-CT)acted as a nondestructive tool for characterizing the microstructure of soil samples exposed to a range of damage levels induced by dry-wet ***,the variations of pore distribution and permeability due to drywet cycling effects were revealed based on three-dimensional(3D)pore distribution analysis and seepage *** to the results,granite residual soils could be separated into four different components,namely,pores,clay,quartz,and hematite,from micro-CT *** reconstructed 3D pore models dynamically demonstrated the expanding and connecting patterns of pore structures during drywet *** values of porosity and connectivity are positively correlated with the number of dry-wet cycles,which were expressed by exponential and linear functions,*** pore volume probability distribution curves of granite residual soil coincide with the χ^(2)distribution curve,which verifies the effectiveness of the assumption of χ^(2)distribution *** pore volume distribution curves suggest that the pores in soils were divided into four types based on their volumes,***,mesopores,macropores,and *** a quantitative and visual perspective,considerable small pores are gradually transformed into cracks with a large volume and a high *** the action of dry-wet cycles,the number of seepage flow streamlines which contribute to water permeation in seepage simulation increases distinctly,as well as the permeability and hydraulic *** calculated hydraulic conductivity is comparable with measured ones with an acceptable error margin in general,verifying the accuracy of seepage simulations based on micro-CT results.

关键词： Granite residual soil Dry-wet cycle X-ray micro computed tomography(micro-CT) Three-dimensional(3D)pore distribution Seepage simulations Permeability

The diffusion of Hong kong cultural values to China's Mainland: a case study in Shenzhen

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Journal of Geographical Sciences 1998年第4期8卷 66-75页

作者： CHOW chun Shing MUI Yuen Yung ZHAO Xiaobin Department of Geography Hong kong Baptist University

s—Since Shenzhen became a special economic zone in 1980, it has achieved spectacular growth in its economy. At the same time, it has opened its door to the importation of foreign goods and cultures,particularly from its neighboring city,Hong ***,Hong kong cultural traits, including materialism, individualism, and the idolization of movie stars and pop singers have become well accepted and commonly followed by the people in Shenzhen. This paper looks into the role of mass communication, particularly television programs, in this process of cultural diffusion, and to assess the cause and effect of such changes on Shenzhen.

关键词： mass media TV program cultural diffusion Hong kong Shenzhen.

Effects of bile salts and divalent cations on the adsorption of norfloxacin by agricultural soils

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Journal of Environmental Sciences 2014年第4期26卷 846-854页

作者： Xuesong kong Shixiang Feng Xu Zhang Yan li School of Resources and Environmental Science Wuhan University

The effects of bile salts （sodium cholate and sodium deoxycholate, 0-20 mmol/L）, divalent cations （Ca^2＋, Mg^2＋, Cu^2＋ and Zn^2＋, 0-20 mmol/L） or pH （3.0-10.0） on the adsorption of norfloxacin by three selected soils （Paddy_H, Paddy_G and Red_J） were systematically studied. Soil adsorption of norfloxacin follows a pseudo second-order kinetics model, and the maximum adsorption capacity has been determined from the nonlinear fit of the Langmuir isotherm model to be 88.8, 88.1 and 63.0 μmol/g for the adsorption onto Paddy_H, Paddy_G and Red_J, respectively. The results indicate that norfloxacin has a high adsorption affinity for the agricultural soils tested and that the organic content of these soils have at least a slight influence on this adsorption. The adsorption of norfloxacin to soils was strongly dependent on pH and exhibited a maximum at approximately pH 6. The presence of divalent cations prominently suppressed the adsorption of norfloxacin by paddy soils, which followed an order of Cu^2＋〉 Mg^2＋〉 Ca^2＋〉 Zn^2＋, and by red soil, which followed an order of Cu^2＋〉 Zn^2＋〉 Ca^2＋〉 Mg^2＋. The adsorption of norfloxacin （by the soils studied） sharply decreased as the amount of bile salts was increased. For uncharged norfloxacin at environmentally relevant pH values, such factors as soil type, exogenous divalent cations and macromolecules significantly altered the environmental fate and transport of norfloxacin between aquatic and soil interfaces.

关键词： adsorption agricultural soil bile salts divalent cation norfloxacin

Relaxation of Selective Constraint on the Ultra-Large Mitochondrial Genomes of Arcidae (Mollusca: Bivalvia)

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Journal of Ocean University of China 2021年第5期20卷 1157-1166页

作者： SUN Shao’e li Qi kong lingfeng Key Laboratory of Mariculture Ministry of EducationOcean University of ChinaQingdao 266003China Laboratory for Marine Fisheries Science and Food Production Processes Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China

The mitochondrial genomes(mitogenomes)are purportedly under selection for smaller size to improve their replica-tion and translation ***,the mitogenomes of Arcidae species are larger than those of other bivalves,and are among the largest metazoan mitogenomes reported to *** order to explore the differences of base composition and selective constraints between the large and small mitogenomes,we compared the mitogenomes of 9 large arcid mitogenomes and 77 small bivalves *** composition analyses indicated that Arcidae mitogenomes have significantly greater GC skews in both their whole genomes and coding *** result suggests that the replication of the large mitogenomes in Arcidae may be slower than those in other bivalves,exposing the parental strand to deamination for a longer *** pressure analyses showed that the mitochondrial protein-coding genes of Arcidae species have significantly higher Ka/Ks ratios than other bivalves,suggesting that they have accumulated more nonsynonymous nucleotide *** protein-coding genes(atp6,cox1-3,nad1,nad4 and nad5)show significant difference for Ka/Ks ratios between the Arcidae and non-Arcidae ***,these divergences are not observed in the nuclear gene within histone *** these observations,we concluded that the large mitoge-nomes of Arcidae species experienced more relaxed selective *** some Arcidae species are more tolerant to hypoxia that can lead to low metabolic rate,the relaxed selective constraints of mitogenomes may be *** study provides new insights into the evolution of Arcidae mitogenomes.

关键词： Arcidae mitochondrial genome genome size relaxed selective constraint

Modeling of irradiation-induced damage and failure behaviors of fuel foil/cladding interface in UMo/Zr monolithic fuel plates

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Nuclear Science and Techniques 2022年第5期33卷 16-29页

作者： Xiang-Zhe kong Xiao-Bin Jian Feng Yan Chang-Bing Tang Zi-Xuan Guo Shu-Rong Ding Yuan-Ming li chun-Yu Yin Institute of Mechanics and Computational Engineering Department of Aeronautics and AstronauticsFudan UniversityShanghai 200433China Science and Technology On Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610213China

Models to describe the damage and fracture behaviors of the interface between the fuel foil and cladding in UMo/Zr monolithic fuel plates were established and numerically *** effects of the interfacial cohesive strength and cohesive energy on the irradiationinduced thermal-mechanical behaviors of fuel plates were *** results indicated that for heterogeneously irradiated fuel plates:(1)interfacial damage and failure were predicted to be initiated near the fuel foil corner with higher fission densities,accompanied by the formation of a large gap after interface failure,which was consistent with some experimental observations;high tensile stresses in the fuel foil occurred near the edges of the failed interface,attributed to through-thickness cracking of the fuel foil,as found in some post-irradiation examinations;(2)the cohesive strength and cohesive energy of the interface both influenced the in-pile evolution behaviors of fuel plates;a lower cohesive strength or cohesive energy resulted in faster interfacial damage;(3)after interface fracture,the thickness of the whole plate increased to a greater degree(by~20%)than that of the samples without interfacial damage,which was attributed to the locally enhanced Mises stresses and the nearby creep deformations around the cracked *** study provided a theoretical basis for assessing failure in fuel elements.

关键词： UMo/Zr Irradiation-inducedthermo-mechanicalbehavior Numericalsimulation Cohesive model Interfacialfailure

New normalized nonlocal hybrid level set method for image segmentation

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Applied Mathematics(A Journal of Chinese Universities) 2017年第4期32卷 407-421页

作者： LOU Qiong PENG Jia-lin kong De-xing WANG chun-lin Department of Mathematics Zhejiang University of Science and Technology The School of Computer Science and Technology Huaqiao University Department of Mathematics Zhejiang University Department of Pediatrics The First HostipalCollege of MedicineZhejiang University

This article introduces a new normalized nonlocal hybrid level set method for image *** to intensity overlapping,blurred edges with complex backgrounds,simple intensity and texture information,such kind of image segmentation is still a challenging *** proposed method uses both the region and boundary information to achieve accurate segmentation *** region information can help to identify rough region of interest and prevent the boundary leakage *** makes use of normalized nonlocal comparisons between pairs of patches in each region,and a heuristic intensity model is proposed to suppress irrelevant strong edges and constrain the *** boundary information can help to detect the precise location of the target object,it makes use of the geodesic active contour model to obtain the target *** corresponding variational segmentation problem is implemented by a level set *** use an internal energy term for geometric active contours to penalize the deviation of the level set function from a signed distance *** last,experimental results on synthetic images and real images are shown in the paper with promising results.

关键词： image segmentation level set method nonlocal method intensity information active contours normalization

Intelligent Vehicle Electrical Power Supply System with Central Coordinated Protection

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Chinese Journal of Mechanical Engineering 2016年第4期29卷 781-791页

作者： YANG Diange kong Weiwei li Bing liAN Xiaomin State Key Laboratory of Automotive Safety and Energy Tsinghua University

The current research of vehicle electrical power supply system mainly focuses on electric vehicles（EV） and hybrid electric vehicles（HEV）.The vehicle electrical power supply system used in traditional fuel vehicles is rather simple and imperfect;electrical/electronic devices（EEDs） applied in vehicles are usually directly connected with the vehicle＇s *** increasing numbers of EEDs being applied in traditional fuel vehicles,vehicle electrical power supply systems should be optimized and improved so that they can work more safely and more *** this paper,a new vehicle electrical power supply system for traditional fuel vehicles,which accounts for all electrical/electronic devices and complex work conditions,is proposed based on a smart electrical/electronic device（SEED） *** as an independent intelligent electrical power supply network,the proposed system is isolated from the electrical control module and communication network,and access to the vehicle system is made through a bus *** results in a clean controller power supply with no electromagnetic interference.A new practical battery state of charge（So C） estimation method is also proposed to achieve more accurate So C estimation for lead-acid batteries in traditional fuel vehicles so that the intelligent power system can monitor the status of the battery for an over-current state in each power *** protection methods are also used to ensure power supply *** and tests on a traditional fuel vehicle are performed,and the results reveal that the battery So C is calculated quickly and sufficiently accurately for battery over-discharge ***-current protection is achieved,and the entire vehicle＇s power utilization is *** traditional fuel vehicles,the proposed vehicle electrical power supply system is comprehensive and has a unified system architecture,enhancing system reliability and security.

关键词： vehicle electrical power supply battery management vehicle electrical system traditional fuel vehicle

Multi-response optimization of Ti-6A1-4V turning operations using Taguchi-based grey relational analysis coupled with kernel principal component analysis

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Advances in Manufacturing 2019年第2期7卷 142-154页

作者： Ning li Yong-Jie Chen Dong-Dong kong School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan 430074 People's Republic of China

Ti-6A1-4V has a wide range of applications, especially in the aerospace field;however, it is a difficultto- cut material. In order to achieve sustainable machining of Ti?6A1-4V, multiple objectives considering not only economic and technical requirements but also the environmental requirement need to be optimized simultaneously. In this work, the optimization design of process parameters such as type of inserts, feed rate, and depth of cut for Ti-6A1-4V turning under dry condition was investigated experimentally. The major performance indexes chosen to evaluate this sustainable process were radial thrust, cutting power, and coefficient of friction at the toolchip interface. Considering the nonlinearity between the various objectives, grey relational analysis (GRA) was first performed to transform these indexes into the corresponding grey relational coefficients, and then kernel principal component analysis (KPCA) was applied to extract the kernel principal components and determine the corresponding weights which showed their relative importance. Eventually, kernel grey relational grade (KGRG) was proposed as the optimization criterion to identify the optimal combination of process parameters. The results of the range analysis show that the depth of cut has the most significant effect, followed by the feed rate and type of inserts. Confirmation tests clearly show that the modified method combining GRA with KPCA outperforms the traditional GRA method with equal weights and the hybrid method based on GRA and PCA.

关键词： Ti-6A1-4V Taguchi method Grey relational analysis (GRA) Kernel principal component analysis (KPCA) Multi-response optimization