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25 March 2018, Volume 38 Issue 2

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Numerical method for solving fuzzy differential equations based on Taylor expansion

YOU Cuilian, HAO Yangyang

2018, 38(2):  113-118.  DOI: 10.3969/j.issn.1000-1565.2018.02.001

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Fuzzy differential equation driven by Liu process is an important tool to deal with dynamic fuzzy problem. When solving fuzzy differential equation,the analytical solution for some fuzzy differential equation driven by Liu process can’t be obtained sometimes,thus it is necessary for us to discuss the numerical method in most situations.In this paper,a numerical method for solving fuzzy differential equation based on fuzzy Taylor expansion is given and its convergence is also proved.

Design of the flexible manipulator and dynamic characteristics analysis of clamping force

LIU Jia,LI Na,HAO Ziyan,JIANG Haiyong,LI Zhaohui

2018, 38(2):  119-125.  DOI: 10.3969/j.issn.1000-1565.2018.02.002

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The flexible manipulator is designed and studied based on that the clamping force controlled by the position control in this paper.Based on the finite element software ABAQUS and dynamic simulation software ADAMS,a dynamic simulation model of the flexible manipulator is established.Different sizes of strawberry are used as the object of analysis,the dynamic simulation analysis of the clamping process of the flexible manipulator is carried out,and the change rule that the clamping force increases linearly with the increase of the driving displacement is obtained.At the same time,the relationship between the driving speed and the instantaneous contact clamping force is also obtained based on the dynamic simulation analysis.On this basis,the prototype of the flexible manipulator is produced,and experiment analysis of clamping process of the flexible manipulator is carried out.The results show that: the flexible manipulator can be achieved nondestructive clamping for fragile strawberry by controlling the displacement and drive speed.Therefore the flexible manipulator can realize clamping of the vulnerable fruit quickly- DOI:10.3969/j.issn.1000-1565.2018.02.002柔性机械手设计与夹取力动态特性仿真分析刘佳,李娜,郝子岩,姜海勇,李朝晖(河北农业大学 机电工程学院,河北 保定 071001)摘 要:设计了一种以驱动位移控制进行夹取力控制的柔性机械手,基于有限元软件ABAQUS及动力学仿真软件ADAMS,建立了柔性机械手的动力学模型.以不同尺寸的草莓为夹取目标物,对柔性机械手夹取过程进行动力学仿真分析,得到了夹取力随驱动位移量的增加呈线性增加的变化规律,同时获得了驱动速度与瞬时接触夹取力的关系曲线.在此基础上,对柔性机械手样机进行实验分析,结果表明:通过控制驱动位移量及速度进给,机械手能够实现对目标物草莓的无损夹取.该柔性机械手基于柔顺机构特性,无需复杂的传感反馈系统,即可实现对浆果类易损果实的快速抓取,为农业自动化收获机器人末端装置设计提供了一个新思路.关键词:柔性机械手;动力学仿真;夹取力;瞬时接触力;动态特性 中图分类号:TP 241.3;TH 112.5 文献标志码:A 文章编号:1000-1565(2018)02-0119-07Design of the flexible manipulator and dynamic characteristics analysis of clamping force LIU Jia,LI Na,HAO Ziyan,JIANG Haiyong,LI Zhaohui(College of Mechanical and Electrical Engineering,Agriculture University of Hebei,Baoding 071001,China)Abstract:The flexible manipulator is designed and studied based on that the clamping force controlled by the position control in this paper.Based on the finite element software ABAQUS and dynamic simulation software ADAMS,a dynamic simulation model of the flexible manipulator is established.Different sizes of strawberry are used as the object of analysis,the dynamic simulation analysis of the clamping process of the flexible manipulator is carried out,and the change rule that the clamping force increases linearly with the increase of the driving displacement is obtained.At the same time,the relationship between the driving speed and the instantaneous contact clamping force is also obtained based on the dynamic simulation analysis.On this basis,the prototype of the flexible manipulator is produced,and experiment analysis of clamping process of the flexible manipulator is carried out.The results show that: the flexible manipulator can be achieved nondestructive clamping for fragile strawberry by controlling the displacement and drive speed.Therefore the flexible manipulator can realize clamping of the vulnerable fruit quickly- 收稿日期:2017-11-03 基金项目:国家自然科学基金资助项目(51305125);河北省自然科学基金资助项目((E2017204037;E2013204110));河北省高等学校科学技术研究优秀青年基金项目(YQ2013007) 第一作者:刘佳(1992—),女,河北唐山人,河北农业大学在读硕士研究生.E-mail:liujia9574@126.com 通信作者:李娜(1981—),女,河北保定人,河北农业大学副教授,博士,主要从事仿生机器人、多体动力学研究.E-mail:res_lina@126.com第2期刘佳等:柔性机械手设计与夹取力动态特性仿真分析without complex sensing and feedback system based on the compliant mechanism characteristics,which provides a new idea for the design of agricultural automation harvesting robot’s end device.

Efficiency enhancement in planar-structured perovskite solar cells with enhanced efficiency by solvent engineering with NMP

YANG Shaopeng,TAO Junlei,CHEN Kang,SUN Yansheng, HUAI Zhaoxiang

2018, 38(2):  126-132.  DOI: 10.3969/j.issn.1000-1565.2018.02.003

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A simple but effective method for improving the perovskite film quality by adding NMP into the precursor solution of perovskite was proposed.By comparing and analyzing the effects of the use of different ratio on the film-forming performances,the optimal additive amount of N-methyl-2-pyrrolidone(NMP)was found that could contribute to a more uniform and non-defective growth of perovskite crystal nucleation,enable preparation of the smooth and compact film with large grain size which can improve the light absorption capacity and reduce charge recombination.The optimized planar-structured perovskite solar cells was fabricated,displaying a 27.11% enhancement as compared to pre-optimized control PSCs.

Finite element simulation of metal plate crack defect

TIAN Xiao,HAO Yuqiang,MA Yan,LI Yanan,ZHOU Qianqian,LIANG Yan

2018, 38(2):  133-139.  DOI: 10.3969/j.issn.1000-1565.2018.02.004

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In this paper,the ansys simulation analysis on aluminum alloy plate,copper plate,and stainless steel plate under the different frequencies with the same artificial defects were carried out.Through the analysis of the magnetic field lines in the electromagnetic field distribution,the test gives the real and the imaginary part of the current,and the corresponding impedance map is obtained.The simulation result points out that the impedance of the coil is changed due to the resistivity,frequency and defects.The conclusion is valuable for practical testing.

Synthesis and in vitro antitumor activity of N-(2-aminophenyl)-4-cinnamamidobenzamide

PENG Xiaoran,WU Jianong,FU Wentao,LI Shenghui,WANG Shuxiang

2018, 38(2):  140-146.  DOI: 10.3969/j.issn.1000-1565.2018.02.005

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A series of benzamide(3a-3j)histone deacetylase inhibitors(HDACi)were synthesized.Their activity for inhibiting histone deacetylase(HDAC)and in vitro cytotoxicity against MCF-7,HeLa,and A549 cell lines were determined by fluorescence analysis and MTT assay.The 2-substituted N-(2-aminophenyl)-4-cinnamamidobenzamides 3b and 3e exhibited high cytotoxicity and activity of inhibiting HDAC.The IC₅₀ value of 3b and 3e for HDAC inhibition were 7.71 and 3.5 μmol/L,and closed to that of chidamide(2.7 μmol/L).The IC₅₀ value of 3b against MCF-7,HeLa,and A549 cell lines were 6.5,6.0,and 5.6 μmol/L;that of 3e against MCF-7,HeLa,and A549 cell lines were 3.9,3.1,and 2.9 μmol/L.The in vitro cytotoxicity of 3b and 3e is closed to that of MS-275(3.5 μmol/L).

Detection of microRNA by catalytic hairpin DNA assembly based on gold nanoparticles

CHENG Yongqiang,ZHAO Yaqing,GAO Shuxin,NIE Xueyu,ZHANG Xuange

2018, 38(2):  147-153.  DOI: 10.3969/j.issn.1000-1565.2018.02.006

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By combining gold nanoparticles(AuNPs)with catalytic hairpin DNA assembly,we develop a new method for the detection of microRNA(miRNA).Firstly,fluorescein-labeled hairpin DNA probe P1 was modified on the surface of AuNPs.The fluorescence signal of P1 is quenched by the AuNPs.When the target miRNA is present,it can hybrid with P1 and form the P1-miRNA intermediates.At the same time,the hairpin structure of P1 is opened.Then the opened P1 can hybrid with the hairpin P2 to form a stable structure,P1-P2,while the fluorophore in P1 is far away from the AuNPs,resulting in the fluorescence emission of fluorescein.Meanwhile,the target miRNA is released and can subsequently induce the multiple assembled reactions of P1 and P2 on the surface of AuNPs.By repeating the cycle,the amplified detection of miRNA is achieved.The method shows a good linear relationship with the miRNA in the concentration range of 50 pmol/L to 2 nmol/L.The detection limit was estimated to be 39 pmol/L. The method is simple,low cost,and used for the detection of miRNA in HepG 2 cells and HeLa cells with satisfactory results.

Adsorption behavior of Pb²⁺on the CdS quantum dots surface

ZHANG Hong,TIAN Jing,MA Gang,DU Baoan

2018, 38(2):  154-158.  DOI: 10.3969/j.issn.1000-1565.2018.02.007

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In this paper,the mono-dispersed CdS quantum dots(QDS)were prepared in water.The fluorescence of the CdS QDs could be intensely quenched by the Pb²⁺,and the quenching effect was used to study the adsorption behavior of the Pb²⁺on the QDs’ surface.The result showed that the quenching effect was strongly influenced by the pH value and the QDs concentration,and involved the number of the Pb²⁺ adsorbed on the QDs’ surface.The adsorption behavior of the Pb²⁺ was consistent with the Langmuir isotherm equation,the relationship between the c/ΔF and c was linear,when the concentration of the Pb²⁺ was between 10^-9 and 10^-3mol/L.According to the Langmuir isotherm equation,the relationship of theΔF and c was also found to be linear at the low Pb²⁺ concentration of 1×10^-8~1×10^-9mol/L.And it was possible to determine the Pb²⁺concentration by using the line as the standard line.The detect limit was as low as 6.0×10^-10 mol/L,the RSD was 2.5%,and the recovery rate was 88.4%~107.2%.

Study on degranulation model of RBL-2H3 cells

LIU Zhongcheng,LIU Shifang,LI Fei,WANG Nannan,ZHANG Nan,YUAN Xin,ZHANG Yanfen

2018, 38(2):  159-167.  DOI: 10.3969/j.issn.1000-1565.2018.02.008

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RBL-2H3 cells are commonly used to research on the pathogenesis of allergic diseases in vitro.In order to establish a detection model of degranulation of RBL-2H3 cells,C48/80 was used as a positive drug to analyze and compare different methods for cells degranulation detection,including the cell morphology observation,trypan blue staining,beta hexosaminidase release rate and calcium ion concentrations.Through studying the concentration and time of C48/80,the optimized drug condition was established for RBL-2H3 cell degranulation induced by C48/80.The results showed that the C48/80 concentration was 60 μg/mL with 40 min,and there was dose-effect relationship between the degree of degranulation and the beta hexosaminidase- DOI:10.3969/j.issn.1000-1565.2018.02.008RBL-2H3细胞脱颗粒模型研究刘中成^1,2,刘世芳^1,2,李飞^1,2,王南南^1,2,张楠^1,2,袁欣^1,2,张艳芬^2,3(1.河北大学 药学院,河北 保定 071002;2.河北省药物质量分析控制重点实验室,河北 保定 071002;3.河北大学 科学技术处,河北 保定 071002)摘 要:RBL-2H3细胞是体外研究变态反应的常用细胞,为了建立RBL-2H3细胞脱颗粒检测模型,以C48/80作为阳性药物,分析比较了细胞形态观测法、台盼蓝染色法、β-氨基己糖苷酶释放率及钙离子质量浓度检测等细胞脱颗粒检测方法.通过对C48/80 作用质量浓度及时间的摸索,建立C48/80刺激RBL-2H3细胞脱颗粒的最佳药物作用条件.结果表明,β-氨基己糖苷酶释放率与细胞脱颗粒程度存在显著量-效关系,且操作简单、结果稳定.C48/80工作质量浓度为60 μg/mL,最佳作用时间40 min.在此基础上,优化了DNP-IgE/DNP-BSA诱导细胞脱颗粒体系,0.4 μg/mL DNP-IgE致敏RBL-2H3细胞过夜,10 μg/mL DNP-BSA诱导细胞,细胞脱颗粒程度最严重.同时发现,不同释放介质对DNP-BSA诱导细胞脱颗粒有显著影响.该结果可为变态反应相关研究提供实验基础.关键词:嗜碱性白血病粒细胞;脱颗粒;变态反应中图分类号:Q291 文献标志码:A 文章编号:1000-1565(2018)02-0159-09Study on degranulation model of RBL-2H3 cellsLIU Zhongcheng^1,2,LIU Shifang^1,2,LI Fei^1,2,WANG Nannan^1,2,ZHANG Nan^1,2,YUAN Xin^1,2,ZHANG Yanfen^2,3(1.College of Pharmaceutical Sciences,Hebei University,Baoding 071002,China;2.Key Laboratory of Pharmaceutical Quality Control of Hebei Province,Baoding 071002,China;3.Office of Science and Technology,Hebei University,Baoding 071002,China)Abstract:RBL-2H3 cells are commonly used to research on the pathogenesis of allergic diseases in vitro.In order to establish a detection model of degranulation of RBL-2H3 cells,C48/80 was used as a positive drug to analyze and compare different methods for cells degranulation detection,including the cell morphology observation,trypan blue staining,beta hexosaminidase release rate and calcium ion concentrations.Through studying the concentration and time of C48/80,the optimized drug condition was established for RBL-2H3 cell degranulation induced by C48/80.The results showed that the C48/80 concentration was 60 μg/mL with 40 min,and there was dose-effect relationship between the degree of degranulation and the beta hexosaminidase- 收稿日期:2017-11-25 基金项目:国家自然科学基金资助项目(81202338);河北省自然科学基金资助项目(H2016201121);河北省高等学校科学技术研究项目(ZD2017010);国家级大学生创新创业训练计划项目(201610075007;201710075016);河北省研究生创新项目(CXZZSS2017014);河北大学实验室开放项目(sy201665) 第一作者:刘中成(1979—),男,河北抚宁人,河北大学教授,博士,主要从事分子药理学研究.E-mail:liuzc@hbu.edu.cn 通信作者:张艳芬(1979—),女,河北邯郸人,河北大学副教授,主要从事微生物生化药学研究.E-mail:zhangjing@hbu.edu.cn第2期刘中成等:RBL-2H3细胞脱颗粒模型研究release rate.Furthermore,this method was simple and reliable,the beta hexosaminidase release rate was applied to detect the degranulation of cells in subsequent experiments.when the model of cell degranulation was successfully induced by DNP-IgE/DNP-BSA,0.4 μg/mL DNP-IgE sensitized RBL-2H3 cells overnight,and 10 μg/mL DNP-BSA induced cells,the cell degranulation was the most serious.The results also showed that the cell degranulation was affected significantly by different release mediums.These results will provide the experimental basis for further studying the allergic diseases.

Over-expression and characterization of a carbonyl reductase gene from Yarrowia lipolytica

ZHANG Honglei,PEI Chaohong,ZHANG Chao,HAN Mengnan,XU Zhidong,LI Wei

2018, 38(2):  168-176.  DOI: 10.3969/j.issn.1000-1565.2018.02.009

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A recombinant E.coli BL21(DE3)/pET-28a-yacrⅡ was constructed,successfully realizing the expression of(S)-specific carbonyl reductase gene(yacrⅡ)from Yarrowia lipolytica.The recombinant enzyme YaCRⅡ was purified using HisTrap HP affinity chromatography and the properties of pure enzyme were exzamined.The results show that the full length of the gene yacrⅡ was 942 bp.The encoding protein(YaCRⅡ)belonged to a medium chain dehydrogenase/reductase family(MDRs)with a molecular weight of 37 ku.YaCRⅡ was used to catalyze reduction of 2-hydroxy acetophenone to give out(S)-1-phenyl-1,2-ethanediol.The optical purity was 99.9%(e.e.).7.85 U/mg of enzymatic activity was tested in the catalytic conversion.The optimal pH was 5 while the optimal temperature was 50 ℃ in the process.The analysis of the substrate structures showed that YaCRⅡ exhibited higher catalytic activity for 2-hydroxy acetophenones with electron withdrawing group at the para position of benzene ring.This work provided an efficient method to prepare highly optical pure alcohols by reduction of the corresponding ketones using enzymatic catalytic system.- DOI:10.3969/j.issn.1000-1565.2018.02.009解脂酵母羰基还原酶基因的克隆表达及酶学性质张红蕾,裴朝红,张超,韩孟楠,徐志栋,李玮(河北大学 化学与环境科学学院,河北 保定 071002)摘 要:通过构建重组菌E.coli BL21(DE3)/pET28a-yacrⅡ,成功实现了解脂酵母(Yarrowia lipolytica)的羰基还原酶(YaCRⅡ)基因(yacrⅡ)的表达.应用HisTrap HP亲和层析分离纯化YaCRⅡ,并对该酶的酶学性质进行了研究.结果表明,yacrⅡ基因序列长942 bp,编码蛋白的分子质量为 37 ku,属于中链醇脱氢酶家族.该酶可以催化不对称还原2-羟基苯乙酮生成(S)-1-苯基-1,2-乙二醇,酶的比活力为7.85 U/mg,光学纯度为99.9%(e.e.).该酶反应的最适pH值为5.0,最适温度为50 ℃.底物结构分析表明,该酶对苯环对位有吸电子基团的2-羟基苯乙酮有较高的催化活性.该酶的发现为制备高光学纯度的手性醇提供了一个新的有效方法.关键词:解脂酵母;羰基还原酶;重组表达;酶学性质中图分类号:Q814.1 文献标志码:A 文章编号:1000-1565(2018)02-0168-09Over-expression and characterization of a carbonyl reductase gene from Yarrowia lipolyticaZHANG Honglei,PEI Chaohong,ZHANG Chao,HAN Mengnan,XU Zhidong,LI Wei(College of Chemistry and Environmental Science,Hebei University,Baoding 071002,China)Abstract:A recombinant E.coli BL21(DE3)/pET-28a-yacrⅡ was constructed,successfully realizing the expression of(S)-specific carbonyl reductase gene(yacrⅡ)from Yarrowia lipolytica.The recombinant enzyme YaCRⅡ was purified using HisTrap HP affinity chromatography and the properties of pure enzyme were exzamined.The results show that the full length of the gene yacrⅡ was 942 bp.The encoding protein(YaCRⅡ)belonged to a medium chain dehydrogenase/reductase family(MDRs)with a molecular weight of 37 ku.YaCRⅡ was used to catalyze reduction of 2-hydroxy acetophenone to give out(S)-1-phenyl-1,2-ethanediol.The optical purity was 99.9%(e.e.).7.85 U/mg of enzymatic activity was tested in the catalytic conversion.The optimal pH was 5 while the optimal temperature was 50 ℃ in the process.The analysis of the substrate structures showed that YaCRⅡ exhibited higher catalytic activity for 2-hydroxy acetophenones with electron withdrawing group at the para position of benzene ring.This work provided an efficient method to prepare highly optical pure alcohols by reduction of the corresponding ketones using enzymatic catalytic system.- 收稿日期:2017-08-23 基金项目:河北省自然科学基金专项-重点项目(B2016201031);河北省高等学校高层次人才科学研究项目(GCC 2014014);河北大学自然科学研究计划项目(3333112) 第一作者:张红蕾(1985—),女,河北保定人,河北大学博士后,主要从事生物酶催化研究.E-mail:zhl0724@126.com 通信作者:李玮(1963—),男,河北晋州人,河北大学教授,博士生导师,主要从事化学合成及生物酶催化研究. E-mail: liweihebeilab@163.com第2期张红蕾等:解脂酵母羰基还原酶基因的克隆表达及酶学性质

Breeding and fermentation conditions optimization of a high-yielding succinic acid producing strain

SU Xiaorao,ZHENG Yanhong,XI Dan,LV Zhitang

2018, 38(2):  177-184.  DOI: 10.3969/j.issn.1000-1565.2018.02.010

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The method of UV mutagenic breeding was carried out for Actinobacillus succinogenes RH to screen succinic acid high-yielding strain.84 mutant strains with relative high succinic acid production were obtained in preliminary screening by TLC method,and a high-yielding mutant strain C4-1 was got by further screening using HPLC.It was found that strain C4-1 remained stable succinic acid producing ability after continuous passage for five generations through the genetic stability analysis.Optimization experiments of carbon source and nitrogen source showed that the optimal carbon source and nitrogen source for succinic acid fermentation were liquefied corn starch(LCS)and corn steep liquor(CSL),respectively.Further experiment showed that the carbon source and nitrogen source can be replaced by liquefied corn flour(LCF)and small amount of CSL so as to reduce the cost.Taking the advantage of optimal conditions,the mutant strain C4-1 resulted in the succinic acid yield of(52.91±0.53)g/L after fermented for- DOI:10.3969/j.issn.1000-1565.2018.02.010丁二酸高产菌株的选育及发酵条件优化苏晓娆¹,郑延红¹,席丹¹,吕志堂^1,2(1.河北大学 生命科学学院,河北省微生物多样性研究与应用重点实验室,河北 保定 071002;2.河北大学 药物化学与分子诊断教育部重点实验室,河北 保定 071002)摘 要:对产琥珀酸放线杆菌RH进行紫外诱变选育,用TLC法初筛得到84株丁二酸产量较高的菌株;对初筛得到的菌株进一步用HPLC法复筛,得到1株高产突变菌株C4-1.经遗传稳定性分析,发现该高产突变株连续传5代后丁二酸产量基本保持稳定.碳源、氮源优化实验表明,突变株C4-1产丁二酸的最适碳源为液化淀粉,最适氮源为玉米浆干粉,且可以采用液化玉米粉添加少量玉米浆干粉代替液化淀粉和玉米浆干粉,以节约成本;在优化条件下突变株C4-1三角瓶发酵60 h,丁二酸产量达到(52.91±0.53)g/L,较原始菌株提高了33.46%.关键词:产琥珀酸放线杆菌;丁二酸;高产突变株;紫外诱变;发酵优化中图分类号:Q939.9 文献标志码:A 文章编号:1000-1565(2018)02-0177-08Breeding and fermentation conditions optimization of a high-yielding succinic acid producing strainSU Xiaorao¹,ZHENG Yanhong¹,XI Dan¹,LÜ Zhitang^1,2(1.Key Laboratory of Microbial Diversity Research and Application of Hebei Province,College of Life Sciences,Hebei University,Baoding 071002,China;2.Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of Ministry of Education,Hebei University,Baoding 071002,China)Abstract:The method of UV mutagenic breeding was carried out for Actinobacillus succinogenes RH to screen succinic acid high-yielding strain.84 mutant strains with relative high succinic acid production were obtained in preliminary screening by TLC method,and a high-yielding mutant strain C4-1 was got by further screening using HPLC.It was found that strain C4-1 remained stable succinic acid producing ability after continuous passage for five generations through the genetic stability analysis.Optimization experiments of carbon source and nitrogen source showed that the optimal carbon source and nitrogen source for succinic acid fermentation were liquefied corn starch(LCS)and corn steep liquor(CSL),respectively.Further experiment showed that the carbon source and nitrogen source can be replaced by liquefied corn flour(LCF)and small amount of CSL so as to reduce the cost.Taking the advantage of optimal conditions,the mutant strain C4-1 resulted in the succinic acid yield of(52.91±0.53)g/L after fermented for- 收稿日期:2017-11-22 基金项目:河北大学自然科学研究计划项目(799207217072) 第一作者:苏晓娆(1991—),女,河北石家庄人,河北大学在读硕士研究生,主要从事微生物遗传育种研究.E-mail:465738724@qq.com 通信作者:吕志堂(1973—),男,河北曲周人,河北大学教授,博士,主要从事微生物资源与系统学研究.E-mail:lzt325@126.com第2期苏晓娆等:丁二酸高产菌株的选育及发酵条件优化60 h in flask with 33.46% high that the original strain.

v-Support vector machine with weight of samples

LI Kai,ZHAI Lulu,CUI Lijuan

2018, 38(2):  185-193.  DOI: 10.3969/j.issn.1000-1565.2018.02.011

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The v-support vector machine(v-SVM)overcomes the difficult problem with selection of parameter for the traditional support vector machine.However,this method does not take into account the effect of different samples in the process of training,which leads to a strong sensitivity to noise or outlier points so that training is easy to be over-fit.In order to solve this problem,an improved v-SVM model is obtained by introducing the weight of the samples for the effect of different samples.A Lagrange method is used to solve the model,and a support vector machine classifier is obtained.To show the effectiveness of the presented method,the experiments are conducted using at two kinds of methods for determining weights of samples on 10 standard data sets from UCI repository,and compared with the performance of C-SVM and v-SVM.

A virtual machine kernel integrity protection method based on hardware virtualization

YANG Xiaohui,XU Ye

2018, 38(2):  194-203.  DOI: 10.3969/j.issn.1000-1565.2018.02.012

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Virtualization technology provides convenience for users,but also provides more attacks.Aiming at the problem of virtual machine kernel integrity,a virtual machine kernel integrity protection method is proposed based on hardware virtualization.It can protect the kernel data,code,and registers by using hardware virtualization extensions.On one hand,a separate page table is created for important kernel data and code,and the access permissions is set for the page table to run in an isolated address space.On the other hand,the use of hardware virtualization “trap” mechanism makes the registers drop to VMM when they are tampered.Based on this,the implementation of the system is given and the system is verified.The experimental results show that this method can detect the common kernel-level rootkits and prevent them to tamper with the system.The final performance cost is controlled within 7%.As a result,this method gives enhanced security and will not have a significant impact on performance.

Action recognition based on visual bag of words and trigonometric function method

ZHANG Xin, WEI Xining,WANG Bing

2018, 38(2):  204-210.  DOI: 10.3969/j.issn.1000-1565.2018.02.013

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Guide wire modeling in virtual vascular interventional surgery system

WANG Guanglei,XU Menglong,GANG Qinguo,XIONG Peng,WANG Hongrui

2018, 38(2):  211-216.  DOI: 10.3969/j.issn.1000-1565.2018.02.014

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Guide wire plays a significant role in the operation.However,current guide wire models are discrete,this paper proposed a new method to build a continuous model of guide wire which can be used in the simulation of the operation.The continuous model can perform different elastic modulus in the different parts.After experimental comparison,it is proved that the continuous model coincide with the real guide wire and the error is 6.21 micrometer every millimeter.The simulation also can display in real time on the computer as well.This method has a prospective use in clinical application.

Application of gray-fuzzy comprehensive evaluation method in transformer condition assessment

LI Sen,ZHANG Shiqi,HU Shunbin

2018, 38(2):  217-224.  DOI: 10.3969/j.issn.1000-1565.2018.02.015

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As the indicators of transformer condition are fuzzy and gray, we propose an assessment method comprehensively based on gray-fuzzy theory. Firstly, the transformer condition assessment indicators system is established. Then, the weight set is made up of fuzzy part and gray part. Its fuzzy part is calculated based on the fuzzy analytic hierarchy process, its gray part is calculated based on the redundancy degree of information and the experiences of experts. Finally, the subordinating degree function is used to describe the relationship between the data and different levels, the incredibility of fuzzy relation of data is described by the gray. The gray fuzzy judgement matrix is established and the transformer condition is assessed. The example shows that the method can assess the transformer condition effectively and the comparison with other evaluation methods proves that this method is more reasonable and effective.