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Journal of Systems Science & Complexity 2015年第4期28卷 925-937页

作者： WU Wuqing wang xiaojing School of Business Renmin University of China Department of Statistics University of Connecticut

In the paper, a novel practical approach to construct a composite indicator （CI） is pro- posed. The key idea is to decide the weights of sub-indicators in constructing a composite indicator by maximizing the sum of squared correlations between the CI and sub-indicators. The CI obtained in this fashion has the maximum sum of squared correlations among all linear estimators. In addition, the simple, exact and explicit solutions of weights are proposed under the condition of non-negative irreducible matrix. Moreover, under this particular condition, the proposed method will become the principal component analysis. For illustration purpose, the proposed novel approach is utilized to cal- culate Sustainable Energy Index and Human Development Index which are two often-used cases to compare models in the literatures. The results the methods of Hatefi, et al. （2010） and Zhou all sub-indicators＇ correlations. show that the power of the proposed method outweigh et al. （2007） in terms of the sum of absolute values of

关键词： Composite indicator Correlation maximum sum of squared correlations (MSSC).

基于计算机筛选与分子模拟技术的宁夏肉牛血红蛋白源抗氧化肽的鉴定

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食品科学 2025年第2期46卷 108-117页

作者：徐斐然王玉王晓静崔伟王永坤周辉王兆明蔡克周章宝徐宝才合肥工业大学食品与生物工程学院动物源食品绿色制造与资源挖掘安徽省重点实验室安徽合肥230601 宁夏农产品质量标准与检测技术研究所宁夏银川750002

采用3种酶解法(碱性蛋白酶(E1组)、胃蛋白酶+胰蛋白酶(E2组)、碱性蛋白酶+胃蛋白酶+胰蛋白酶(E3组))制备宁夏肉牛血红蛋白酶解产物,并筛选出抗氧化活性最佳组分;利用氨基酸分析和液相色谱-串联质谱鉴定分子质量<3 kDa酶解产物的氨基酸... 详细信息

采用3种酶解法(碱性蛋白酶(E1组)、胃蛋白酶+胰蛋白酶(E2组)、碱性蛋白酶+胃蛋白酶+胰蛋白酶(E3组))制备宁夏肉牛血红蛋白酶解产物,并筛选出抗氧化活性最佳组分;利用氨基酸分析和液相色谱-串联质谱鉴定分子质量<3 kDa酶解产物的氨基酸组成和序列,利用计算机分析技术筛选出潜在的抗氧化肽,并验证其活性;通过分子模拟技术进一步研究宁夏肉牛血红蛋白抗氧化肽的作用机理。结果表明,E3组酶解效果最佳,超滤后<3 kDa的组分表现出更佳的抗氧化活性(1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基和2,2’-联氮-双(3-乙基苯并噻唑啉-6-磺酸)(2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid),ABTS)阳离子自由基清除率的半数抑制浓度(half maximal inhibitory concentration,IC_(50))分别为(18.382±0.023)mg/mL和(0.246±0.012)mg/mL);E3(分子质量<3 kDa)组富含疏水性和芳香族氨基酸,且鉴定和筛选出4条活性最佳的抗氧化肽,氨基酸序列分别为DWGHSW、VFYPW、GTGW和TYFPHF;其中,VFYPW表现出最高的DPPH自由基清除率(IC_(50):(0.350±0.013)mg/mL)和ABTS阳离子自由基清除率(IC_(50):(9.482±0.122)μg/mL),其次为DWGHSW;氢键和疏水作用使DWGHSW和VFYPW与Keap1蛋白(PDB ID:2FLU)形成稳定的复合物。该研究可为宁夏肉牛血红蛋白肽作为天然源抗氧化补充剂的应用提供理论依据,有助于宁夏肉牛血液资源的高值化利用。

关键词：计算机筛选分子模拟宁夏肉牛血红蛋白抗氧化肽鉴定

ANALYSES ON NONLINEAR COUPLING OF MAGNETO-THERMO-ELASTICITY OF FERROMAGNETIC THIN SHELL—II:FINITE ELEMENT MODELING AND APPLICATION

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Acta Mechanica Solida Sinica 2009年第3期22卷 197-205页

作者： Xingzhe wang xiaojing Zheng Key Laboratory of Mechanics on Western Disasters and Environment Ministry of Education of China College of Civil Engineering and Mechanics Lanzhou University Lanzhou 730000 China

Based on the generalized vaxiational principle of magneto-thermo-elasticity of a ferromagnetic thin shell established （see, Analyses on nonlinear coupling of magneto-thermo- elasticity of ferromagnetic thin shell--I）, the present paper developed a finite element modeling for the mechanical-magneto-thermal multi-field coupling of a ferromagnetic thin shell. The numerical modeling composes of finite element equations for three sub-systems of magnetic, thermal and deformation fields, as well as iterative methods for nonlinearities of the geometrical large-deflection and the multi-field coupling of the ferromagnetic shell. As examples, the numerical simulations on magneto-elastic behaviors of a ferromagnetic cylindrical shell in an applied magnetic field, and magneto-thermo-elastic behaviors of the shell in applied magnetic and thermal fields are carried out. The results are in good agreement with the experimental ones.

关键词： ferromagnetic thin shell magneto-thermo-elasticity nonlinear coupling finite element method

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Fault Feature Extraction of Rolling Bearing Based on an Improved Cyclical Spectrum Density Method

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Chinese Journal of Mechanical Engineering 2015年第6期28卷 1240-1247页

作者： LI Min YANG Jianhong wang xiaojing School of Mechanical Engineering University of Science and Technology Beijing

The traditional cyclical spectrum density（CSD） method is widely used to analyze the fault signals of rolling bearing. All modulation frequencies are demodulated in the cyclic frequency spectrum. Consequently, recognizing bearing fault type is difficult. Therefore, a new CSD method based on kurtosis（CSDK） is proposed. The kurtosis value of each cyclic frequency is used to measure the modulation capability of cyclic frequency. When the kurtosis value is large, the modulation capability is strong. Thus, the kurtosis value is regarded as the weight coefficient to accumulate all cyclic frequencies to extract fault features. Compared with the traditional method, CSDK can reduce the interference of harmonic frequency in fault frequency, which makes fault characteristics distinct from background noise. To validate the effectiveness of the method, experiments are performed on the simulation signal, the fault signal of the bearing outer race in the test bed, and the signal gathered from the bearing of the blast furnace belt cylinder. Experimental results show that the CSDK is better than the resonance demodulation method and the CSD in extracting fault features and recognizing degradation trends. The proposed method provides a new solution to fault diagnosis in bearings.

关键词： cyclostationary cyclical spectrum density rolling bearing fault diagnosis

Water quality evaluation of Haihe River with fuzzy similarity measure methods

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Journal of Environmental Sciences 2013年第10期25卷 2041-2046页

作者： xiaojing wang Zhihong Zou Hui Zou School of Economic and Management Beihang University Department of Applied Mathematics College of ScienceChina Agricultural University

Fuzzy similarity measures, which are used to judge the closeness of two fuzzy sets, are presented to evaluate the water quality of the Haihe River. Based on the membership functions and coefficient of variation as the weights, four fuzzy similarity measures （including Lattice similarity measure, Hamming similarity measure, Euclidean similarity measure and the max-min similarity measure） are used to classify the 299 samples into the proper water quality standard ranks. The results are compared with the traditional distance discriminant methods. The calculation of two traditional distance discriminant methods （both Euclidean distance and absolute value distance） is also based on the use of coefficients of variation as the weights. Without the Lattice similarity measure, for this method loses some information, the correct assignment of samples classified into the same water quality ranks is 75.92% with the other three similarity measures and two distance discriminant methods. This result shows the reliability of the five methods. Only considering the three similarity measures, there were only 1.01% of the samples that did not classify to the same ranks, while the corresponding ratio of the two distance discriminant methods was 5.69%. The results of leave-one-out cross validation show that more than 88% of the samples are classified to the proper ranks, which demonstrates that the similarity measures are suitable to evaluate the water quality of the Haihe River.

关键词： similarity measure distance discriminant coefficient of variation membership function

Effects of Zn, Zn-Al and Zn-P Additions on the Tensile Properties of Sn-Bi Solder

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Acta Metallurgica Sinica(English Letters) 2014年第6期27卷 1159-1164页

作者： xiaojing wang Yanlai wang Fengjiang wang Ning Liu Jianxin wang School of Material and Science Engineering Jiangsu University of Science and Technology Key Laboratory of Semiconductor Photovoltaic Technology of Inner Mongolia Autonomous Region School of Physical Science and Technology Inner Mongolia University

Effects of Zn, Zn-Al and Zn-P additions on melting points, microstructures, tensile properties, and oxidation behaviors of Sn-40 Bi lead-free solder were investigated. The experimental results show that the addition of these three types of elements can refine the microstructures and improve the ultimate tensile strength（UTS） of solder alloys. The fractographic analysis illustrates that ductile fracture is the dominant failure mode in tensile tests of Sn-40Bi-2Zn（SBZ）and Sn-40Bi-2Zn-0.005Al（SBZA） specimens, while brittle fracture is the controlled manner in Sn-40Bi-2Zn-0.005P（SBZP） and Sn-58 Bi solders. XPS analysis indicates that trace amounts of both Al and P additives in solder can improve the antioxidant capacity, whereas only the additive of Al in solder can reduce the thickness of oxidation film.

关键词： Sn-Bi Tensile test Microstructure

Carbon nanotubes in biology and medicine:An overview

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Chinese Science Bulletin 2012年第2期57卷 167-180页

作者： wang xiaojing LIU Zhuang Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices Institute of Functional Nano and Soft MaterialsSoochow UniversitySuzhou 215123China

Rapid development in the field of nanomedicine is bringing novel opportunities for improved disease diagnosis and drug *** various nanomaterials involved in nanomedicine,carbon nanotubes(CNTs) possessing a unique one-dimensional structure with interesting intrinsic mechanical,physical,and chemical properties have been extensively explored for a wide range of applications in biology and *** review article provides an overview of how CNTs are used in different aspects of biomedicine including drug delivery and cancer treatment,bio-sensing,biomedical imaging,as well as tissue *** recent developments,future perspective,and major challenges in this field are discussed.

关键词：生物医学成像碳纳米管生物学药物输送纳米材料一维结构 CNTs 化学性质

Expression pattern of GASA,downstream genes of DELLA,in Arabidopsis

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Chinese Science Bulletin 2008年第24期53卷 3839-3846页

作者： ZHANG ShengChun wang xiaojing College of Life Sciences South China Normal University Guangdong Provincial Key Lab of Biotechnology for Plant Development Guangzhou 510631 China

Separation and functional research of related components involved in gibberellins(GAs) signaling are important to clarify the mechanism of GA *** on the downstream components of DELLA,the key factor of the GA signaling pathway,is limited at ***(GA-Stimulated in Arabidopsis) family contains 15 genes usually regulated by GA in Arabidopsis *** GASA proteins have a cleavable signal peptide in N terminus and a conserved GASA domain including 12 cysteines in C ***-PCR analysis revealed that the expression of GASA4 and GASA6 were down-regulated,but GASA1 and GASA9 were up-regulated in the DELLA mutants,gai-t6 and rga-24,as well as the double mutant,consisting with the results that GASA4 and GASA6 were induced,but GASA1 and GASA9 were inhibited by exogenous *** addition,the expression patterns of other GASA genes were regulated by GA and ABA,separately or *** of GASA genes were expressed in roots,stems,leaves,flowers and developing *** gene driven by the promoters of GASA6,GASA7,GASA8,GASA9,GASA10,GASA11 and GASA12 were used as reporters and it was found that all GASA genes expressed in the growing and differentiating organs and abscission zones,suggesting the role of these genes in cell growth and *** study provided an important basis for functional study of the GASA gene family in the GA and ABA signaling pathway.

关键词： GASA DELLA GA ABA 基因

Nonlinear uncertainty impact of geometric variations on aerodynamic performance of low-pressure turbine blades with ultra-high loading under extreme operational conditions

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Chinese Journal of Aeronautics 2024年第5期37卷 281-300页

作者： xiaojing wang Zhengping ZOU Chao FU Pengcheng DU School of Energy and Power Engineering Beihang UniversityBeijing 100191China National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics Beihang UniversityBeijing 100191China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China

Uncertainty impact of random geometric variations on the aerodynamic performance of low-pressure turbine blades is considerable,which is further amplified by the current ultra-high-lift design trend for weight ***,this uncertainty impact on ultra-highly loaded blades under extreme operational conditions near the margins with potential large-scale open separation is focused on in this *** is demonstrated that this impact is significant,unfavourable,and nonlinear,which is clearly severer under extreme *** addition to the overall attenuation and notable scattering of specific performance,the operational margins with open separation are also notably scattered with great risk of significant *** scattering and nonlinearity are dominated by the variations in leading-edge *** thinning of leading edge triggers local transition,enhancing downstream friction and reducing resistance to open separation,which is further exacerbated by operational ***,the opposite thickening yields less benefit,implying *** unfavourable impact highlights the need for robust aerodynamic design,where both a safer operational condition and a more robust blade are indispensable,i.e.,a compromise among performance,weight,and *** the necessary limitation of loading levels,a mid-loaded design is recommended to reduce adverse pressure gradients in both the leading edge and rear region of the suction side,which helps to decrease the susceptibility of the transition and open separation to random *** improvements can also be achieved by appropriately thickening the leading edge.

关键词： Ultra-highly loaded turbine blade Geometric variations Uncertainty analysis Operational margins Robust aerodynamic design Nonlinearity

Modulation recognition of MIMO radar signal based on joint HOS and SNR algorithm

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Journal of Systems Engineering and Electronics 2014年第2期25卷 226-236页

作者： xiaojing wang Ying Xiong Yunhao Li Bin Tang School of Electronic Engineering University of Electronic Science and Technology of China

This paper presents a joint high order statistics （HOS） and signal-to-noise ratio （SNR） algorithm for the recognition of multiple-input multiple-output （MIMO） radar signal without a priori knowledge of the signal parameters. This method is capable of recognizing the MIMO radar signal as well as discriminating it from single-carrier signal adopted by conventional radar. Meanwhile, the sub-carrier number of the none-coding MIMO radar signal is estimated. Extensive simulations are carried out in different operating conditions. Simulation results prove the feasibility and indicate that the recognition probability could reach over 90% when the value of SNR is above 0 dB.

关键词： modulation recognition multiple-input multiple-output(MIMO) radar signal high order statistics (HOS).