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TiN/CrN multilayered hard coatings with TiCrN interlayer deposited by a filtered cathodic vacuum arc technique

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Journal of University of Science and Technology Beijing 2004年第5期11卷 420-424页

作者： ChengmingLi QiHe GangLin XiaojunSunt WeizhongTang FanxiuLu 不详 collegeofengineering ChinaAgriculturalUniversityBijing100083China LanzhouInstituteofChemistryandPhysics Chinese＇AcademyofScienceLanzhou730000China

TiN/CrN multilayered hard coatings with TiCrN interlayer were deposited onhigh speed steel substrates by using a filtered cathodic vacuum arc technique. The structure andcomposition of the coatings were characterized by scanning electron microscopy (SEM) and Augerelectron spectroscopy (AES). A high adhesion of up to 80 N was demonstrated by scratching tests forthe multi-layered coatings. Nanoindentation tests were performed to determine the hardness andelastic modulus of the coatings as a function of the multiplayer modulation period. It was observedthat the hardness of the multilayered coatings is higher than those of either TiN or CrN singlecoatings, and it increases with decreasing modulation periods, which is consistent with predictionsfrom the Hall-Petch type strengthening mechanism, though at small modulation periods, deviation fromthe Hall-Petch relation has been observed for the multilayered coatings. The life-span of drillscoated with TiN/CrN multilayered is triple as long as that coated with TiN layer.

关键词： TiN/CrN multilayer hard coatings TiCrN interlayer hardness drilling life

Combinatorial model of solute transport in porous media

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Journal of Zhejiang University Science 2004年第8期5卷 966-969页

作者：张妙仙张丽萍 collegeofengineering ZhejiangForestryUniversityLin＇an311300China InstituteofSoilandWaterResourcesandEnvironmentalScience CollegeofEnvironmentalandResourceScienceZhejiangUniversityHangzhou310029China

Modeling of solute transport is a key issue in the area of soil physics and hydrogeology. The most common approach (the convection-dispersion equation) considers an average convection flow rate and Fickian-like dispersion. Here,we propose a solute transport model in porous media of continuously expanding scale, according to the combinatorics principle. The model supposed actual porous media as a combinative body of many basic segments. First, we studied the solute transport process in each basic segment body, and then deduced the distribution of pore velocity in each basic segment body by difference approximation, finally assembled the solute transport process of each basic segment body into one of the combinative body. The simulation result coincided with the solute transport process observed in test. The model provides useful insight into the solute transport process of the non-Fickian dispersion in continuously expanding scale.

关键词：组合模型扩展模型组合数学质量转换溶解转换过程多孔渗水介质

Reinvigorating the Wiener-Hopf technique in the pursuit of understanding processes and materials

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National Science Review 2021年第2期8卷 11-13页

作者： David Abrahams Xun Huang Anastasia Kisil Gennady Mishuris Michael Nieves Sergei Rogosin Ilya Spitkovsky IsaacNewtonInstituteforMathematicalSciences collegeofengineering PekingUniversity DepartmentofMathematics UniversityofManchester DepartmentofMathematics AberystwythUniversity SchoolofComputingandMathematics KeeleUniversity FacultyofEconomics BelarusianStateUniversity ScienceandMathematics NewYorkUniversityAbuDhabi

The Wiener-Hopf(WH) method was created in 1931, by Norbert Wiener and Eberhard Hopf, to deliver exact solutions to integral equations with convolutiontype kernels on a half-line. It appears that this problem is closely related to that posed by Riemann in 1857 on the problem concerning the construction of a Fuchsian system of differential equations with given singular points and a prescribed monodromy group. This later became known as the 21 st Hilbert problem. The WH method is a powerful and long-standing tool that served as a catalyst in broadening the applicability of Fourier analysis, owing to the essential characteristics of analytic functions. Employing the Fourier transform(FT) to the integral equation leads to a RiemannHilbert(RH) problem on the real axis:

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The Application of a Numerical Model to Coastal Surface Water Waves

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Journal of Ocean University of China 2005年第2期4卷 177-184页

作者： ZOUHuazhi LIHuajun LIUXiaodong LIUAixia collegeofengineering OceanUniversityofChinaQingdao266071P.R.China

Based on the Navier-Stokes Equations (NSE), numerical simulation with fine grids is conducted to simulate the coastal surface wave changes, including wave generation, propagation, transformation and interactions between waves and structures. This numerical model has been tested for the generation of the desired incident waves, including both regular and random waves. Some numerical results of this model are compared with available experimental data. In order to apply this model to actual cases, boundary conditions are considered in detail for different shoreline types (beach or breakwater, slope or vertical wall, etc. ). Finally, the utility of the model to a real coastal area is shown by applying it to a fishing port located in Shidao, Rongcheng, Shandong Province, P.R. China.

关键词：波传播数值仿真海洋气候 Navier-Stokes函数边界条件

Experimental Study on the Effectiveness of TLDs under Wave Loading

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Journal of Ocean University of Qingdao 2002年第1期1卷 80-86页

作者： DONGSheng LIHuajun LUMing TomotsukaTakayama collegeofengineering OceanUniversityofQingdaoQingdao266003P.R.China DisasterPreventionResearchInstitute KyotoUniversityKyoto611-0011Japan

The objective of this study is to experimentally investigate the effectiveness of Tuned Liquid Dampers (TLDs) for suppressing the dynamic response of a platform structure subjected to wave loading and to explore the applicability of TLDs for suppressing the structural vibration of fixed offshore platforms. The experimental model is scaled according to a full size platform by matching its dynamic properties. Rectangular and circular TLDs of various sizes and water depths are examined. The experiments were performed in a 2-D wave flume. The effectiveness of TLDs is evaluated based on their response reduction. By observing the performance and the behavior of TLDs through laboratory experiments, the effects of a number of parameters including container shape, container size, number of dampers, frequency ratio, mass ratio, and incident wave characteristics are investigated.

关键词：液体阻尼器调谐直角坐标导管架平台波浪槽

Nonlinear Fitting Method of Long-Term Distributions for Statistical Analysis of Extreme Negative Surge Elevations

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Journal of Ocean University of Qingdao 2003年第1期2卷 106-111页

作者： DONGSheng LIFengli JIAOGuiying collegeofengineering OceanUniversityofChinaQingdao266071P.R.China ConstructionofCommissionofQingdaoMunicipalGovernment Qingdao266071P.R.China

Hydrologic frequency analysis plays an important role in coastal and ocean engineering for structural design and disaster prevention in coastal areas. This paper proposes a Nonlinear Least Squares Method (NLSM), which estimates the three unknown parameters of the Weibull distribution simultaneously by an iteration method. Statistical test shows that the NLSM fits each data sample well. The effects of different parameter-fitting methods, distribution models, and threshold values are also discussed in the statistical analysis of storm set-down elevation. The best-fitting probability distribution is given and the corresponding return values are estimated for engineering design.

关键词：非线性统计分析频率海洋工程灾害预防

SOLVING MINIMUM SPANNING TREE PROBLEM WITH DNA COMPUTING

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Journal of Electronics(China) 2005年第2期22卷 112-117页

作者： LiuXikui LiYan XuJin collegeofengineering＆Tech. XuzhouNormalUniversityXuzhou271019China DeptofControlScience＆Eng. HuazhongUniv.ofScienceandTech.Wuhan430074China

Molecular programming is applied to minimum spanning problem whose solution requires encoding of real values in DNA strands. A new encoding scheme is proposed for real values that is biologically plausible and has a fixed code length. According to the characteristics of the problem, a DNA algorithm solving the minimum spanning tree problem is given. The effectiveness of the proposed method is verified by simulation. The advantages and disadvantages of this algorithm are discussed.

关键词： DNA计算机遗传算法最小生成树分子设计

Selection of Environmental Conditions for Nearshore Structure Design

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Journal of Ocean University of China 2004年第1期3卷 111-114页

作者： DONGSheng GANBuhong HAOXiaoli collegeofengineering OceanUniversityofChinaQingdao266071P.R.China ShengliOffshoreDrillingCompany Dongying257055P.R.China

Different from the traditional one dimensional extreme value statistical method, practical design criteria for nearshore structure design are presented based on joint probability theory in this paper. The proposed procedure considers the combined effect of tide level, huge waves and wind affecting coastal structures. The Importance Sampling Procedure (ISP) is utilized to solve the joint distribution of non Gaussian correlated multivariate distributions. The calculation results show that the ISP is a simulating technique with the advantages of efficiency and high convergency. Finally the environmental conditions are given using this technique for near shore structure design in the Qingdao area.

关键词：近海工程结构设计统计方法潮汐波浪风

Chemical vapor deposition growth of large-scale hexagonal boron nitride with controllable orientation

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Nano Research 2015年第10期8卷 3164-3176页

作者： Xiuju Song Junfeng Gao Yufeng Nie Teng Gao Jingyu Sun Donglin Ma Qiucheng Li Yubin Chen Chuanhong Jin Alicja Bachmatiuk Mark H. Rummeli Feng Ding Yanfeng Zhang Zhongfan Liu CenterforNanochemistry(CNC) BeijingScienceandEngineeringCenterforLowDimensionalCarbonMaterialsBeijingNationalLaboratoryforMolecularSciencesCollegeofChemistryandMolecularEngineeringAcademyforAdvancedInterdisciplinaryStudiesPekingUniversityBeijing100871China DepartmentofMaterialsScienceandEngineering CollegeofEngineeringPekingUniversityBeijing100871China InstituteofTextilesandClothing HongKongPolytechnicUniversityHongKongChina StateKeyLaboratoryofSiliconMaterials DepartmentofMaterialsScienceandEngineeringZhejiangUniversityHangzhou310027China CentreofPolymerandCarbonMaterials PolishAcademyofSciencesM.Curie-Sklodowskiej34Zabrze41-819Poland DepartmentofEnergyScience DepartmentofPhysicsSungkyunkwanUniversitySuwon440-746RepublicofKorea IBSCenterforIntegratedNanostructurePhysics InstituteforBasicScience(IBS)Daejon305-701RepublicofKorea

有一致厚度的大域的六角形的硼氮化物(h-BN ) 的化学蒸汽免职(CVD ) 合成是很挑战性的，主要由于这材料的极其高的成核密度。此处，我们报导晶片规模的成功的生长，有大单人赛水晶的领域尺寸的高质量的 h-BN 单层电影，吗直到~ 72 ?????... 详细信息

有一致厚度的大域的六角形的硼氮化物(h-BN ) 的化学蒸汽免职(CVD ) 合成是很挑战性的，主要由于这材料的极其高的成核密度。此处，我们报导晶片规模的成功的生长，有大单人赛水晶的领域尺寸的高质量的 h-BN 单层电影，吗直到~ 72 ??????????????????????????慮潮档湡敮獬???????慮潮畴敢??洠獥灯牯????  ？？

关键词：化学气相沉积生长空间生长取向六角氮化硼 Cu(111) 可控密度泛函理论成核密度