Journal of Hebei University(Natural Science Edition)

Asymptotic properties for a porous media parabolic equations

XUE Yingzhen,FENG Heping

2019, 39(5): 449-454. DOI: 10.3969/j.issn.1000-1565.2019.05.001

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In order to describe the reaction diffusion problems of three media in physics, such as mechanics of porous media, fluid mechanics, gas flow and so on, the asymptotic behavior of a class of parabolic equations of porous media,with 3 variables coupled with a weighted nonlocal boundary and a nonlinear internal source is studied.The upper and lower solutions of the first eigenvalue are broken, and the upper and lower solutions of the equations are constructed by using the ordinary differential equation method, and the comparison theorem is quoted. It is proved that the whole existence of the solution of the parabolic equations of porous media with the power function and the exponential function fully coupled and the sufficient conditions for the solution in the finite time blasting are obtained.On the basis of the existing results, provide more theoretical support for porous media and fluid mechanics are achieved.

Establishments of Asian option pricing formulas for uncertain currency model

GAO Rong, WANG Chun, ZHANG Zanmei

2019, 39(5): 455-458. DOI: 10.3969/j.issn.1000-1565.2019.05.002

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Asian option is a significant financial derivative instrument, which is one of the most popular path-dependent options. Its income is decided by the average value of underly asset within the whole lifetime of the option. Influenced by the dynamic uncertainty of risk, the interest rate in foreign exchange market is assumed to be modeled by uncertain process and its law of change obeys an uncertain differential equation. In order to hedge against risks from the foreign exchange market, the bank provides a contract for investors to give them a kind of right instead of obligation to buy foreign exchange at a knock exchange rate. Naturally, for possessing such right, the investor needs to pay for the contract. Hence, based on the uncertain foreign exchange model, this paper studies the Asian option problem. Combining uncertainty theory and fair price principle, the pricing formulas of geometric average Asian option are deduced.

Measurement method of the standard volume of bell provers

LIU Chenkui, QU Hongqiang, CHEN Shiyan, NIU Lina, XING Jingfang

2019, 39(5): 459-465. DOI: 10.3969/j.issn.1000-1565.2019.05.003

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In order to accurately measure the standard volume of large volume and high accuracy bell provers, the measurement methods of dimension and industrial digital photogrammetry are selected as the research method on the basis of reference verification regulation and new standard volume measurement methods at worldwide.Through building mathematical model, collecting test datas and comparing analysis, it is proved that industrial digital photogrammetry technology can meet the requirement of traceability, and the method has high automation degree, high measurement accuracy and high subdivision degree, and can construct the geometry of the inner cavity effectively, which provides the possibility for the follow-up study of start and stop measurement at any point of bell provers.

Research on urban earthquake shelter planning ——Taking Baoding city as an example

QIE Luwen, ZHAO Ruoxu, LIU Jing, SONG Pengyan, ZHANG Jianwen

2019, 39(5): 466-472. DOI: 10.3969/j.issn.1000-1565.2019.05.004

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As the modernization of the city accelerates, the quality of people's living standards has been improvedret the function of preventing and reducing earthquake in cities has lagged far behind the development of town. Based on the current situation of earthquake shelter planning in Baoding City, some problems of the existing emergency shelters are analyzed, and some countermeasures and suggestions to strengthen the construction of urban emergency shelters are proposed. Taking the basic situations of earthquake shelters in universities and urban park as examples, corresponding planning proposals are presented according to their shortcomings. At the same time, the awareness of Baoding residents earthquake shelter was investigated by means of questionnaires as well as advertising relevant knowledge and information of earthquake shelters.

Absorption characteristics of Λ-type and V-type joint atomic systems by the modulation of coupling fields

YUAN Xiaoxian,WANG Longlong,SHI Yafang,ZHOU Wenguang,LIU Yi,WANG Ying,LI Xiaoli

2019, 39(5): 473-477. DOI: 10.3969/j.issn.1000-1565.2019.05.005

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A theoretical study of the absorption characteristics of Λ-type and V-type joint atomic systems by the modulation of coupling fields is performed based on quantum mechanics. Using perturbation method to solve density matrix equations of motion in the system, the probing spectrum is numerically simulated under weak probing field conditions. Using the coupling field 2 as the linked field, we connect V-type system composed of coupling field 1 and coupling field 2 and Λ-type system composed of coupling field 2 and probing field. The line width and multi-window feature of EIT are controlled by tuning the Rabi frequency of coupling field 1, and the nonlinear characteristics of EIT are controlled by tuning the frequency detuning of the coupling field 2.

Experimental study on discharge characteristics of argon plasma brush and its surface modification of PET

XU Huimin, TANG Xiao, XU Longfei, ZHAO Na, GAO Kun, JIA Pengying

2019, 39(5): 478-483. DOI: 10.3969/j.issn.1000-1565.2019.05.006

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With blowing argon, a uniform planar plume with pulsed discharges is generated in ambient air at atmospheric pressure through a plasma brush excited by a direct current power supply. Results indicate that the core of the planar plume is very uniform, while its two edges are much brighter than the core region. Meanwhile, the length of the argon plume increases with increased gas flow rate. This argon brush is then used to improve hydrophilicity of polyethylene terephthalate(PET)surface. After a single scan of the plasma brush on the PET surface, a uniform surface modification is achieved with an improved hydrophilic width of about 24.0 mm. The polar groups are contained in oxidized materials, which are observed by scanning electron microscopy. Moreover, these polar groups have increased number density and scale with increasing the gas flow rate. Furthermore, water contact angle is found to decrease with increasing the gas flow rates until it reaches an almost constant value.

Synthesis of hyaluronic acid-dextran block polymers containing hydrazone

LIU Haofan, LI Xin,HU Liandong

2019, 39(5): 484-490. DOI: 10.3969/j.issn.1000-1565.2019.05.007

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Hyaluronic acid hydrazide(HA-NHNH₂)and oxidized dextran 40(Odex 40)were synthesized by using biodegradable and non-toxic hyaluronic acid and dextran 40. The optimum method for the synthesis of oxidized dextran 40 was determined by oxidation degree. The above two substances were reacted with each other to obtain a hyaluronic acid-oxidized dextran block copolymer(HA-Hz-Odex)containing a hydrazine bond. The NMR study shows that the HA-Hz-Odex block copolymers containing hydrazine bonds have been successfully synthesized.

Simultaneous determination of melatonin and vitamin B6 by dual wavelength high performance liquid chromatography with fluorescence detection

LIU Liyan, ZHANG Hongxin, HUANG Shan, LIAN Haichen, BAI Jie, HAN Yanmei, WU Suhuan

2019, 39(5): 491-497. DOI: 10.3969/j.issn.1000-1565.2019.05.008

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An analytical method of dual wavelength high performance liquid chromatography with fluorescence detector was developed for simultaneous determination of melatonin and vitamin B6 in health products. The effects of different ultrasonic time and cleaning time of melatonin and vitamin B6 in health products were investigated, and the chromatographic conditions were optimized. The assay was carried out- DOI:10.3969/j.issn.1000-1565.2019.05.008双波长HPLC-荧光法同时测定褪黑素和维生素B6刘丽艳¹,张宏馨^1,2,黄珊²,廉海晨¹,白洁^1,2,韩艳梅¹,吴素焕¹(1. 河北大学医学综合实验中心,河北保定 071000;2.河北大学公共卫生学院,河北保定 071000)摘要:建立了双波长高效液相色谱-荧光检测器同时检测保健品中褪黑素和维生素B6含量的方法. 考察了不同超声时间、清洗次数对保健品中褪黑素和维生素B6溶出量的影响,并对色谱条件进行了优化. 采用Inertsil-100A C18色谱柱(4.6 mm×250 mm,5 μm),以甲醇-水(65∶35,体积比)为流动相,流速1.0 mL/min,柱温25 ℃,进样量10 μL. 采用双波长法,0~4 min,λ_ex=332 nm,λ_em=397 nm;4 min后,λ_ex=286 nm,λ_em=352 nm. 在优化的样品预处理条件、色谱条件下,维生素B6和褪黑素分别在0.1~100 μg/L和1.0~1 000 μg/L内线性关系良好(r≥0.998),最低检出限分别为3×10^-3 μg/L和3×10^-2 μg/L;定量限分别为1×10^-2 μg/L和1×10^-1 μg/L,平均回收率分别为99.07%和97.97%(n=3),相对标准偏差为0.04%~0.98%. 本方法检测快速,灵敏,重现性较好,可用于保健品中褪黑素和维生素B6的同时测定以及市售保健品的质量控制.关键词:褪黑素;维生素B6;高效液相色谱;荧光检测;双波长中图分类号:O657.39 文献标志码:A 文章编号:1000-1565(2019)05-0491-07Simultaneous determination of melatonin and vitamin B6 by dual wavelength high performance liquid chromatography with fluorescence detectionLIU Liyan¹, ZHANG Hongxin^1,2, HUANG Shan², LIAN Haichen¹, BAI Jie^1,2, HAN Yanmei¹, WU Suhuan¹ (1.Medical Comprehensive Experimental Center of Hebei University, Hebei University, Baoding 071000, China; 2. College of Public Health, Hebei University, Baoding 071000, China)Abstract: An analytical method of dual wavelength high performance liquid chromatography with fluorescence detector was developed for simultaneous determination of melatonin and vitamin B6 in health products. The effects of different ultrasonic time and cleaning time of melatonin and vitamin B6 in health products were investigated, and the chromatographic conditions were optimized. The assay was carried out- 收稿日期:2018-06-29 基金项目:河北省卫计委医学重点项目(20170189);河北大学医学专科专项资金项目(2014A2001);河北大学校内引进人才科研启动项目(2014-284);国家自然科学基金资助项目(21605035);河北省自然科学基金资助项目(B2014201162);保定市科学技术与发展指导计划项目(12ZF054);河北大学中西部提升综合实力专项资金资助项目(20150505);河北大学实验室开放基金项目(sy201672);河北大学医学部第一批教育教学改革研究课题项目(YXB01-F-05) 第一作者:刘丽艳(1984—),女,河北唐山人,河北大学实验师,主要从事色谱分析、荧光分析、生化分析、生物传感器等研究. E-mail:liyanliu.ok@163.com 通信作者:张宏馨(1971—),女,河北保定人,河北大学副教授,主要从事预防医学与实验动物学教学与研究.E-mail:lzwen5653@163.com韩艳梅(1964—),女,河北保定人,河北大学教授,主要从事生理学等研究.E-mail:hanyanmei6465@sina.com第5期刘丽艳等:双波长HPLC-荧光法同时测定褪黑素和维生素B6on a Inertsil-100A C₁₈ column(4.6 mm ×250 mm, 5 μm)with methanol-water(65∶35, V/V)as the mobile phase, the flow rate was 1.0 mL/min, the column temperature was 25 ℃, and the injection volume was 10 μL. The dual wavelength method was used to make accurate quantitative analysis at the best wavelength of vitamin B6 and melatonin. At the time of 0~4 min, the excitation wavelength and emission wavelength were placed at 332 nm and 397 nm respectively, and the vitamin B6 was detected. After 4 min, the excitation wavelength and the emission wavelength were converted to 286 nm and 352 nm respectively, and melatonin was detected. Under the optimized sample pretreatment conditions and chromatographic conditions, the calibration curves of vitamin B6 and melatonin showed good linearities within the mass concentrations of 0.1~100 μg/L and 1.0~1 000 μg/L(r > 0.998), respectively. The detection limits for vitamin B6 and melatonin were 3×10^-3 μg/L and 3×10^-2 μg/L. The average recoveries was 99.07% and 97.97%(n=3), respectively. The relative standard deviations(RSDs)varied from 0.04% to 0.98%. This method is rapid, sensitive, reproducible, and requires short detection time. A sample can be tested in 6min. The method can be employed for the simultaneous determination of melatonin and vitamin B6 in health care products and the quality control of marketed healthcare products.

Quantitative determination and comparison the contents of tannic acid and resveratrol in red wine

ZHANG Yuanyuan, LI Jiajia, HAN Xue, ZHANG Jianping, CHU Li

2019, 39(5): 498-503. DOI: 10.3969/j.issn.1000-1565.2019.05.009

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To determine the content of tannic acid and resveratrol in red wine, and to identify the main functional substances in red wine about the “French paradox”, the high performance liquid chromatography(HPLC)was used to quantitative determine the contents of tannic acid and resveratrol in four different brands red wine. The results showed that the content of tannic acid in red wine was 0.81~1.44 mg /mL, and the content of resveratrol was 0.14~2.49 mg /L, that is to say, the content of tannin was about 10³ times higher than resveratrol. Considering the more and more pharmacological studies on the cardiovascular activity of tannic acid, the results suggested that tannic acid may also be the main functional substance to explain the French paradox.

Progress in biosafety study of nano-hydroxyapatite on bone-associated cells

2019, 39(5): 504-509. DOI: 10.3969/j.issn.1000-1565.2019.05.010

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A review of the biosafety of Nano-hydroxyapatite is briefly summarized,in cluding the effects of Nano-hydroxyapatite on bone formation and osteoblastic cell activity.The influence of Nano-hydroxyapatite on osteoblast and dispersion of stromal cells osteogenesis, function and mechanism of formation of bone in the body are introduced.The effects of Nano- hydroxyapatite on cell vibility through different concentration and size of cell, and the reseach progress about the effects of Nano- hydroxyapatite on cell vibility through the reactive oxygen、mitochondrial and lysosome pathways are also concluded.

Protective role of resveratrol on housefly oxidative stress induced by ultraviolet light

LIN Dongdong, HOU Yalu, TANG Ting, LIU Fengsong

2019, 39(5): 510-515. DOI: 10.3969/j.issn.1000-1565.2019.05.011

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This study aims to explore the antioxidant mechanism of resveratrol in housefly larvae exposed to oxidative stress induced by ultraviolet light. The Musca domestica aconitase protein were obtained with prokaryotic expressing system, and used for preparing rabbit polyclonal antiserum. The larvae antioxidant value, including reactive oxygen species(ROS)level, malondialdehyde(MDA)content and superoxide dismutase(SOD)activity, Musca domestica aconitase(MdACO)expression and MdACO activity were detected after treatment with ultraviolet light and resveratrol. The result shows that, compared with normal controls, ROS levels, malondialdehyde(MDA)content, superoxide dismutase(SOD)activity and MdACO expression increased dramatically, and MdACO activity declined about 35% in larvae due to exposure to ultraviolet radiation. In corstrast the ROS levels, malondialdehyde(MDA)content, MdACO expression and MdACO activity treating with resveratrol and ultraviolet light had no significant differences with the normal control group. Our study demonstrates that resveratrol can protect against oxidative damage induced by ultraviolet light.- DOI:10.3969/j.issn.1000-1565.2019.05.011白藜芦醇对紫外线诱导家蝇氧化损伤的保护作用蔺冬冬,侯亚璐,唐婷,柳峰松(河北大学生命科学学院,河北省动物系统学与应用重点实验室,河北保定 071002)摘要:为了研究白藜芦醇(Res)在紫外线照射家蝇幼虫氧化应激模型中的抗氧化作用,本实验利用原核表达系统获得家蝇顺乌头酸酶重组蛋白,并制备多克隆抗体;对家蝇幼虫分别进行紫外线照射和投喂白藜芦醇后再进行紫外线照射的处理,利用试剂盒检测不同处理组的氧化指标,包括活性氧(ROS)水平、丙二醛(MDA)含量以及超氧化物歧化酶(SOD)活性的变化;同时检测不同处理组的家蝇顺乌头酸酶(MdACO)表达水平及活性变化.实验结果显示紫外线照射后的家蝇幼虫体内ROS水平、MDA含量、SOD活性以及MdACO的蛋白表达水平显著高于正常对照组,MdACO活性比正常对照组降低约35%;投喂白藜芦醇后再进行紫外线照射的家蝇幼虫ROS水平、MDA含量、MdACO的表达水平及酶活性与未经白藜芦醇和紫外线处理的空白组无明显差别.结果表明白藜芦醇可以保护机体应对紫外线引起的氧化应激.关键词:家蝇;白藜芦醇;顺乌头酸酶;氧化应激中图分类号:Q966 文献标志码:A 文章编号:1000-1565(2019)05-0510-06Protective role of resveratrol on housefly oxidative stress induced by ultraviolet lightLIN Dongdong, HOU Yalu, TANG Ting, LIU Fengsong(Key Laboratory of Zoological Systematics and Application of Hebei Province, College of Life Sciences, Hebei University, Baoding 071002, China)Abstract: This study aims to explore the antioxidant mechanism of resveratrol in housefly larvae exposed to oxidative stress induced by ultraviolet light. The Musca domestica aconitase protein were obtained with prokaryotic expressing system, and used for preparing rabbit polyclonal antiserum. The larvae antioxidant value, including reactive oxygen species(ROS)level, malondialdehyde(MDA)content and superoxide dismutase(SOD)activity, Musca domestica aconitase(MdACO)expression and MdACO activity were detected after treatment with ultraviolet light and resveratrol. The result shows that, compared with normal controls, ROS levels, malondialdehyde(MDA)content, superoxide dismutase(SOD)activity and MdACO expression increased dramatically, and MdACO activity declined about 35% in larvae due to exposure to ultraviolet radiation. In corstrast the ROS levels, malondialdehyde(MDA)content, MdACO expression and MdACO activity treating with resveratrol and ultraviolet light had no significant differences with the normal control group. Our study demonstrates that resveratrol can protect against oxidative damage induced by ultraviolet light.- 收稿日期:2019-02-20 基金项目:国家自然科学基金资助项目(31572327);河北省重点实验室运行补助费资助项目(14967611D) 第一作者:蔺冬冬(1986—),女,河北兴隆人,河北大学实验师,主要从事无脊椎动物分子免疫学研究. E-mail:15231219183@139.com 通信作者:柳峰松(1976—),男,河北任丘人,河北大学教授,主要从事分子免疫学研究.E-mail:liufengsong@hbu.edu.cn第5期蔺冬冬等:白藜芦醇对紫外线诱导家蝇氧化损伤的保护作用

Impact of parental obesity on sperm epigenetic intergenerational inheritance

GE Shaoqin, ZHU Mengmeng, FENG Ruoyu, SONG Qi, WANG Lixin

2019, 39(5): 516-521. DOI: 10.3969/j.issn.1000-1565.2019.05.012

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Paternal obesity can lead to some defects of epigenetic modification in sperm, which is passed on to the offspring with a serious impact on the health. This article reviews the abnormal epigenetic modifications such as DNA methylation, histone modifications, and non-coding RNAs due to paternal obesity and the mechanism of intergenerational inheritance of paternal obesity, as well as the epigenetic effects from parental obesity on the health of parents and children, providing reference materials for prevention and diagnosis of the related diseases in offspring.

Photodynamic antibacterial and antitumor activity of photosensitizer T1

ZHAO Zhanjuan, MA Yingying, LIU Yameng, YANG Yanxi, SHANG Yazhen, ZHAO Jianxi

2019, 39(5): 522-528. DOI: 10.3969/j.issn.1000-1565.2019.05.013

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To investigate the photodynamic therapy(PDT)effect of the same photosensitivities on tumor cells and drug-resistant bacteria, colon cancer cells(CT-26)and methicillin-resistant Staphylococcus aureus(MRSA)selected in vitro. The phagocytosis of photosensitizer T1 by MRSA and CT-26 was detected by laser confocal microscopy. The light and dark response curves of T1 to CT-26 cells and MRSA were determined by MTT staining and colony counting. The results showed that both CT-26 cells and MRSA absorbed T1 rapidly in a time-dependent and concentration-dependent manner. T1-mediated PDT showed strong inhibition on CT-26 cells and MRSA, and CT-26 cells and MRSA showed strong fluorescence signal of T1 by confocal laser microscopy. The proliferation of MRSA and CT-26 cells were significantly inhibited through T1-mediated PDT, and PDT may become a new method for the treatment of tumors which caused by bacterial infection in the future, providing experimental data for the clinical application of PDT.- DOI:10.3969/j.issn.1000-1565.2019.05.013光敏剂T1的光动力抗菌与抗肿瘤活性赵占娟¹,马莹莹²,刘亚萌¹,杨焱惜¹,商亚贞³,赵建喜³(1. 河北大学医学院,河北保定 071002;2.河北大学公共卫生学院,河北保定 071002;3.河北大学附属医院放射科,河北保定 071002)摘要:为了探讨同种光敏剂对肿瘤细胞及耐药细菌的光动力(photodynamic therapy,PDT)治疗效果,体外选取了金黄色葡萄球耐药菌(methicillin-resistant Staphylococcus aureus, MRSA)及结肠癌细胞(CT-26),采用激光共聚焦显微镜检测MRSA及CT-26对半乳糖酞菁类光敏剂T1的吞噬,四甲基偶氮唑蓝染色法(MTT法)和菌落计数法检测T1对CT-26细胞和MRSA的光反应及暗反应浓度曲线;结果发现CT-26细胞及MRSA对T1吸收迅速且呈时间和浓度依赖性. T1介导的PDT对CT-26细胞和MRSA均具有较强的抑制,激光共聚焦显微镜也显示T1在CT-26细胞和MRSA内都有很强的荧光信号.T1介导的PDT能明显抑制MRSA及CT-26细胞的增殖,未来有可能成为一种治疗由细菌感染引起肿瘤的新方法,为PDT的临床应用提供实验数据.关键词:光敏剂;光动力疗法;细菌;肿瘤细胞中图分类号:R735 文献标志码:A 文章编号:1000-1565(2019)05-0522-07Photodynamic antibacterial and antitumor activity of photosensitizer T1ZHAO Zhanjuan¹, MA Yingying², LIU Yameng¹, YANG Yanxi¹, SHANG Yazhen³, ZHAO Jianxi³(1. College of Basic Medical Science, Hebei University, Baoding 071002, China;2. College of Public Health, Hebei University, Baoding 071002, China;3. Department of Radiology, Affiliated Hospital of Hebei University, Baoding 071002, China)Abstract: To investigate the photodynamic therapy(PDT)effect of the same photosensitivities on tumor cells and drug-resistant bacteria, colon cancer cells(CT-26)and methicillin-resistant Staphylococcus aureus(MRSA)selected in vitro. The phagocytosis of photosensitizer T1 by MRSA and CT-26 was detected by laser confocal microscopy. The light and dark response curves of T1 to CT-26 cells and MRSA were determined by MTT staining and colony counting. The results showed that both CT-26 cells and MRSA absorbed T1 rapidly in a time-dependent and concentration-dependent manner. T1-mediated PDT showed strong inhibition on CT-26 cells and MRSA, and CT-26 cells and MRSA showed strong fluorescence signal of T1 by confocal laser microscopy. The proliferation of MRSA and CT-26 cells were significantly inhibited through T1-mediated PDT, and PDT may become a new method for the treatment of tumors which caused by bacterial infection in the future, providing experimental data for the clinical application of PDT.- 收稿日期:2019-03-04 基金项目:河北省卫生厅资助项目(20170833);河北大学大学生创新训练计划项目(2018307;2019027);河北大学医学院2018年实验室开放项目第一作者:赵占娟(1974—),女,河北博野人,河北大学副教授,博士,主要从事激光医学方向研究. E-mail:zhaozhanjuanv@163.com 通信作者:赵建喜(1969—),男,河北保定人,河北大学教授,主要从事影像诊断方向研究.E-mail:jianxizhaov@163.com第5期赵占娟等:光敏剂T1的光动力抗菌与抗肿瘤活性

Effect of drought stress on Viburnum sargentii Koehne photosynthetic characteristics

YANG Jianwei, ZHAO Dan,SUN Guifang, LIU Jiaxiang,ZHAO Yixuan, SHI Baosheng

2019, 39(5): 529-535. DOI: 10.3969/j.issn.1000-1565.2019.05.014

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Using Viburnum sargentii Koehne seedlings as test materials, using pot-set four water moisture gradients, correspondins to 95% of water holding capacity the largest field(control), 75%(mild drought), 55%(moderate drought)and 35%(severe drought), the effect of soil moisture on V. sargentii photosynthetic parameters was studied.The results show that:the net photosynthetic rate(P_n), stomatal conductance(G_s)and transpiration rate(T_r)of V. sargentii reduced with soil water decreasing and intercellular mole fraction of CO₂(x_{__{co_{_₂})in mild and moderate drought stress decreased significantly, but increased under severe drought stress. When the drought stress V. sargentii light saturation point(LSP), maximum net photosynthetic- DOI:10.3969/j.issn.1000-1565.2019.05.014干旱胁迫对天目琼花光合特征的影响杨建伟^1,2,3,赵丹¹,孙桂芳¹,刘嘉翔¹,赵艺璇¹,史宝胜¹(1.河北农业大学园林与旅游学院,河北保定 071000;2.兴隆县林业和草原局,河北兴隆 067300;3.兴隆县住房和城乡建设局,河北兴隆 067300)摘要:以天目琼花(Viburnum sargentii Koehne)幼苗为实验材料,采用盆栽控水法设置4个水分梯度,分别为田间最大持水量的95%(对照)、75%(轻度胁迫)、55%(中度胁迫)和35%(重度胁迫),研究土壤水分对天目琼花光合参数的影响.结果表明:天目琼花的净光合速率(P_n)、气孔导度(G_s)和蒸腾速率(T_r)随着土壤水分递减而减少,胞间CO₂摩尔分数(x_{__{co_{_₂})在轻度和中度干旱胁迫时下降,在严重干旱时显著升高.随着胁迫程度的加剧,天目琼花的光饱和点(LSP)、最大净光合速率(P_nmax)、暗呼吸速率(R_d)和表观量子效率(AQY)显著减少,光补偿点(LCP)显著增加(P<0.01).天目琼花的最大荧光(F_m)、最大光化学效率(F_v/F_m)和光系统Ⅱ(PSⅡ)的量子效率(F_v/F_o)随着土壤水分递减而减少,初始荧光(F_o)显著升高(P<0.01);随着土壤含水量的下降能量分配比率参数φ_Po、Ψ_o、φ_Eo逐渐下降,φ_Do逐渐增加;代表单位反应中心活性的参数ABS/RC、TR_o/RC、ET_o/RC和DI_o/RC逐渐升高.研究表明,在轻度和中度干旱胁迫下天目琼花光合作用能力的降低主要是由气孔限制因素引起的,重度干旱主要是非气孔限制因素引起的.关键词:天目琼花;干旱胁迫;光合特征中图分类号:S688 文献标志码:A 文章编号:1000-1565(2019)05-0529-07Effect of drought stress on Viburnum sargentii Koehne photosynthetic characteristicsYANG Jianwei^1,2,3, ZHAO Dan¹,SUN Guifang¹, LIU Jiaxiang¹,ZHAO Yixuan¹, SHI Baosheng¹(1.College of Landscape Architecture and Tourism, Hebei Agricultural University, Baoding 071000,China;2.Forestry and Grassland Bureau of Xinglong County,Xinglong 067300,China;3.County Housing and Urban-Rural Development Bureau of Xinglong,Xinglong 067300,China)Abstract: Using Viburnum sargentii Koehne seedlings as test materials, using pot-set four water moisture gradients, correspondins to 95% of water holding capacity the largest field(control), 75%(mild drought), 55%(moderate drought)and 35%(severe drought), the effect of soil moisture on V. sargentii photosynthetic parameters was studied.The results show that:the net photosynthetic rate(P_n), stomatal conductance(G_s)and transpiration rate(T_r)of V. sargentii reduced with soil water decreasing and intercellular mole fraction of CO₂(x_{__{co_{_₂})in mild and moderate drought stress decreased significantly, but increased under severe drought stress. When the drought stress V. sargentii light saturation point(LSP), maximum net photosynthetic- 收稿日期:2018-06-26 基金项目:河北省林业厅资助项目(1704487);河北省林业科学研究院资助项目(17226320D) 第一作者:杨建伟(1994—),男,河北张家口人,河北农业大学硕士,主要从事园林植物研究.E-mail:443801835@qq.com 通信作者:史宝胜(1969—),男,河北高阳人,河北农业大学教授,博士生导师,主要从事园林植物栽培与育种研究.E-mail:baoshengshi@163.com第5期杨建伟等:干旱胁迫对天目琼花光合特征的影响rate(P_nmax), dark respiration rate(R_d)and apparent quantum efficiency(AQY)significantly reduced, light compensation point(LCP)increased significantly(P <0.01).The maximum fluorescence(F_m), maximum photochemical efficiency(F_v/F_m)and PSⅡ quantum efficiency(F_v/F_o)decreased with the soil water decreasing, and the initial fluorescence(F_o)(P < 0.01)was significantly increased.When the drought stress energy distribution ratio parameters,φ_Po、Ψ_o、φ_Eo gradually decline, heass ipation ratio of quantum φ_Do increase gradually.As the drought stress intensifies, the parameters of plant unit reaction center activity ABS/RC, TR_o/RC, Et_o/RC and DI_o/RC increase gradually. Studies have shown that:the decrease of the photosynthesis was mainly caused by stomatal factors, and the net photosynthetic rate was caused by the non-stomatal factors in severe drought stress.}}}}}}

Weighted zeroth-order stochastic gradient descent algorithm with variance reduction

LU Shuxia, ZHANG Luohuan, CAI Lianxiang, SUN Lili

2019, 39(5): 536-546. DOI: 10.3969/j.issn.1000-1565.2019.05.015

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Stochastic gradient descent(SGD)is one of the most efficient methods for solving machine learning problems.However, for imbalanced data, the probability of most class points being extracted is much higher than that of a few class points, which easily leads to unbalanced calculation.When it is non-differentiable or not easy to take the derivative on the objective function, the calculation cost is too large or cannot be calculated.A single sample gradient is used to approximately replace the full gradient in each iteration, which will inevitably produce variance.This seriously affects the classification performance of the algorithm.In order to solve the above problems, the weighted zeroth-order stochastic gradient descent algorithm with variance reduction is presented.Considering the margin distribution of data, the margin mean term is introduced into the objective function, which gives smaller weights to most class of samples, and a larger weight to a few classes of samples.In solving the optimization problem, the zeroth-order optimization method is used to estimate the gradient and the variance reduction strategy is introduced.Experiments- DOI:10.3969/j.issn.1000-1565.2019.05.015带有方差减小的加权零阶随机梯度下降算法鲁淑霞¹,张罗幻¹, 蔡莲香¹,孙丽丽²(1.河北大学数学与信息科学学院,河北省机器学习与计算机智能重点实验室,河北保定 071002;2.河北省教育考试院,河北石家庄050091)摘要:随机梯度下降(stochastic gradient descent,SGD)算法是机器学习问题中的高效求解方法之一.但是,对于非平衡数据,传统的随机梯度下降算法,在训练时多数类点被抽到的概率远大于少数类点,易导致计算不平衡;对于目标函数不可导或不易求导的问题,计算代价太大或无法进行计算;在每次迭代中利用单个样本梯度近似代替全梯度,这必然会产生方差,严重影响算法的分类性能.针对上述问题,提出了带有方差减小的加权零阶随机梯度下降算法,考虑了数据的间隔分布情况,在目标函数中引入了间隔均值项,并对多数类样例赋予了较小的权值,对少数类样例赋予较大的权值.在对优化问题的求解中,采用零阶优化的方法对梯度进行估计,并且引入了方差减小策略.在一些非平衡数据集上的实验验证了所提算法的有效性,并有效解决了上述问题.关键词:零阶优化;随机梯度下降;方差减小;非平衡数据;支持向量机中图分类号:TP181 文献标志码:A 文章编号:1000-1565(2019)05-0536-11Weighted zeroth-order stochastic gradient descentalgorithm with variance reductionLU Shuxia¹, ZHANG Luohuan¹, CAI Lianxiang¹, SUN Lili²(1.Key Laboratory of Machine Learning and Computational Intelligence of Hebei Province, College of Mathematics and Information Science, Hebei University, Baoding 071002,China; 2.Hebei Education Examinations Authority, Shijiazhuang 050091,China)Abstract: Stochastic gradient descent(SGD)is one of the most efficient methods for solving machine learning problems.However, for imbalanced data, the probability of most class points being extracted is much higher than that of a few class points, which easily leads to unbalanced calculation.When it is non-differentiable or not easy to take the derivative on the objective function, the calculation cost is too large or cannot be calculated.A single sample gradient is used to approximately replace the full gradient in each iteration, which will inevitably produce variance.This seriously affects the classification performance of the algorithm.In order to solve the above problems, the weighted zeroth-order stochastic gradient descent algorithm with variance reduction is presented.Considering the margin distribution of data, the margin mean term is introduced into the objective function, which gives smaller weights to most class of samples, and a larger weight to a few classes of samples.In solving the optimization problem, the zeroth-order optimization method is used to estimate the gradient and the variance reduction strategy is introduced.Experiments- 收稿日期:2019-01-06 基金项目:河北省自然科学基金资助项目(F2015201185) 第一作者:鲁淑霞(1966—),女,河北保定人,河北大学教授,博士,主要从事机器学习方向研究. E-mail:cmclusx@126.com第5期鲁淑霞等:带有方差减小的加权零阶随机梯度下降算法on some imbalanced datasets demonstrate the effectiveness of the proposed algorithm which effectively solve the above problems.

Real-time simulation of high frequency voltage inverters with multiple switching events

GUO Liang,CHI Song,SHI Wen

2019, 39(5): 547-553. DOI: 10.3969/j.issn.1000-1565.2019.05.016

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With the development of the third wide ban-gap semiconductors, the frequency of electronics is becoming higher and higher. In real time simulation of high frequency power electronics, simulation step size and switching time are often inconsistent and multiple switching events may occur. The traditional algorithm dealing with multiple switching events is too complex to be used in real time simulation. To improve the precision of real time simulation multiple switching events have been classified and different algorithms which are suitable in real time simulation have been proposed. Finally the algorithms are used in voltage source inverter, the simulation precision has been proved in MATLAB and the real time feasibility also has been proved. The simulation result of RT-LAB shows the new algorithm which considers multiple switching events is better than the traditional real time algorithm and also can be used in real time simulation.- DOI:10.3969/j.issn.1000-1565.2019.05.0016计及多重开关事件的高频电压源逆变器实时仿真郭亮^1,2,3,迟颂^1,2,3,施文^1,2,3(1. 河北工业大学电气工程学院,天津 300131;2. 省部共建电工装备可靠性与智能化国家重点实验室,天津 300131;3.河北省电磁场与电器可靠性重点实验室,天津 300131)摘要:随着碳化硅等第3代宽禁带半导体的问世以及电力电子元件小型化潮流的发展,电力电子元件逐渐高频化.高频电力电子实时仿真中常常会有仿真步长和开关时刻不一致以及多重开关事件的出现,传统的针对多重开关事件的高精度离线仿真算法由于算法过于复杂,并不具备可实时性.为了提高高频下实时仿真的仿真精度,对高频下多重开关事件进行了分类,并对不同类的多重开关事件提出了相应的适用于实时的仿真算法,最终以电压源逆变器为例通过MATLAB仿真对算法的仿真精度进行验证并通过时序分析验证了算法实时的可行性.RT-LAB仿真平台的仿真结果也表明,本文提出的计及多重开关事件的仿真算法精度优于传统实时算法,并且具有实时仿真的可行性.关键词:高频电力电子;实时仿真;多重开关事件;电压源逆变器中图分类号:TM464 文献标志码:A 文章编号:1000-1565(2015)05-0547-07Real-time simulation of high frequency voltage inverters with multiple switching events GUO Liang^1,2,3,CHI Song^1,2,3,SHI Wen^1,2,3(1. College of Electrical Engineering, Hebei University of Technology, Tianjin 300131, China; 2. State Key Laboratory of Reliability and Intelligence of Electrical Equipment, Tianjin 300131, China;3.Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability of Hebei Province, Tianjin 300131,China)Abstract: With the development of the third wide ban-gap semiconductors, the frequency of electronics is becoming higher and higher. In real time simulation of high frequency power electronics, simulation step size and switching time are often inconsistent and multiple switching events may occur. The traditional algorithm dealing with multiple switching events is too complex to be used in real time simulation. To improve the precision of real time simulation multiple switching events have been classified and different algorithms which are suitable in real time simulation have been proposed. Finally the algorithms are used in voltage source inverter, the simulation precision has been proved in MATLAB and the real time feasibility also has been proved. The simulation result of RT-LAB shows the new algorithm which considers multiple switching events is better than the traditional real time algorithm and also can be used in real time simulation.- 收稿日期:2019-03-06 基金项目:河北省引进海外高层次人才“百人计划”资助项目(E2015100007) 第一作者:郭亮(1995—),男,河北保定人,河北工业大学在读硕士研究生. E-mail:1742364529@qq.com 通信作者:迟颂(1972—),男,河北唐山人,河北工业大学教授,博士,主要从事高频电力电子变换技术及应用,高精度电力电子控制算法,电力电子系统实时仿真方面的研究工作.E-mail:chis@hebut.edu.cn第5期郭亮等:计及多重开关事件的高频电压源逆变器实时仿真

Simulation of the torque control system of in-wheel BLDC motor for electric vehicle

WANG Tao, CUI Yuanyuan, LI Zhiyuan

2019, 39(5): 554-560. DOI: 10.3969/j.issn.1000-1565.2019.05.017

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The torque control system of in-wheel BLDC motor for electric vehicle was researched. The control system aims at controlling motor output torque and meeting required motor output torque that is transformed by driver required power. The characteristic of motor control system lies in the feedback of motor output torque.The MATLAB/Simulink software is used to build a vehicle simulation platform driving ECE40. The simulation results show that the developed motor torque control system can control motor to meet the driverneed of controlling vehicle speed, and the estimation law can estimate the motor output torque successfully. The strategy for BLDC motor control improves the performance of electric vehicle drive system, and make the motor generate the electric magnetic torque efficiently, steadily and quickly.

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