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基于Levenberg-Marquadt的非线性最小二乘新型换流变压器漏感矩阵识别法

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电工技术学报 2013年第4期28卷 212-220页

作者：赵志宇罗隆福许加柱李勇陈清玉张杰宁志毫湖南大学电气与信息工程学院长沙410082

在对新型换流变压器的保护研究中,漏感参数的识别尤为重要。鉴于该换流变压器的特殊绕组结构,本文首次推导出以漏感参数的矩阵形式来表征这种结构的特殊性,并提出一种基于Levenberg-Marquadt的非线性最小二乘算法用于此漏感参数矩阵识别... 详细信息

在对新型换流变压器的保护研究中,漏感参数的识别尤为重要。鉴于该换流变压器的特殊绕组结构,本文首次推导出以漏感参数的矩阵形式来表征这种结构的特殊性,并提出一种基于Levenberg-Marquadt的非线性最小二乘算法用于此漏感参数矩阵识别,在对正常及各种外部故障情况下的仿真中应用该方法均正确识别了漏感参数矩阵,且求得的参数误差很小,而对各种内部故障情况下漏感参数矩阵的辨识误差较大,能有效地与前者区分。该漏感参数的识别方法不仅能降低数学建模的冗余性,而且还能处理新型换流变压器的电压电流数据中的共线性问题,从而准确快捷地识别出漏感参数矩阵,并且避免识别过程陷入局部最优。本文提出的新型换流变压器漏感参数的快速识别方法,为进一步研究新型换流变压器的保护打下一定的理论基础。

关键词：换流变压器参数辨识漏感非线性最小二乘共线性

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农田生态沟渠效能研究

黑龙江生态工程职业学院学报 2017年第5期30卷 5-7,68页

作者： Tang Van Tai Tran ngoc Binh Tang Thi thanh Sang Le Hong Hanh 东南大学土木工程学院江苏南京210096 Vinh Medical University Vinh University

传统混凝土沟渠主要使用浆砌石、钢筋混凝土等材料建造成排水沟渠,难以有效去除农田污水中的富营养化,引起河道污染~[1]。本实验在调查太湖运河沿岸农田的污染情况的基础上,设计并建造复合生态沟渠示范工程,然后根据季节差异种植复合的... 详细信息

传统混凝土沟渠主要使用浆砌石、钢筋混凝土等材料建造成排水沟渠,难以有效去除农田污水中的富营养化,引起河道污染~[1]。本实验在调查太湖运河沿岸农田的污染情况的基础上,设计并建造复合生态沟渠示范工程,然后根据季节差异种植复合的植物。通过观察植物生长情况研究生态沟渠的植生价值,检测生态沟渠的水质变化情况以检验农田污水富营养化的去除效能。

关键词：生态沟渠农田污水太滆运河

德意志联邦共和国教师培训的经验及其对越南教师培训改革的启示

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佳木斯职业学院学报 2017年第5期33卷 202-203页

作者： [越南]BUI Minh Duc NGUYEN thanh Hung NGUYEN Thi ngoc Be DAO Thi Viet Anh 越南河内师范大学二越南顺化师范大学心理教育系

为了满足普通教育计划改革的要求,需要改革教师培训计划。旨在建设和发展一支数量足够、结构合理、高素质、高水平的教师队伍,提高各师范大学教师培训工作的质量与效果。本文主要就处于世界领先水平的德意志联邦共和国教师培训工作进行... 详细信息

为了满足普通教育计划改革的要求,需要改革教师培训计划。旨在建设和发展一支数量足够、结构合理、高素质、高水平的教师队伍,提高各师范大学教师培训工作的质量与效果。本文主要就处于世界领先水平的德意志联邦共和国教师培训工作进行介绍,力图找出越南可借鉴的经验,提出了越南教师培训改革的若干建议。

关键词：经验教师培训质量效果教师

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越南义安省沿海红树林保护与修复方法探析

法制与经济 2016年第12期25卷 154-156页

作者： Tang Thi thanh sang Tran ngoc Binh Nguyen Nhu Anh Tang Vm Tai 越南荣市大学越南荣市东南大学土木工程学院江苏南京210096

红树林是热带气候地区特有的景观,也是国家珍贵的自然资源。红树林在修复生态多样性、防治自然灾害、保护生态环境、促进经济发展等方面发挥着重要作用。受自然和人为因素的影响,红树林的面积正快速减少,探寻保护和修复红树林的方法已... 详细信息

红树林是热带气候地区特有的景观,也是国家珍贵的自然资源。红树林在修复生态多样性、防治自然灾害、保护生态环境、促进经济发展等方面发挥着重要作用。受自然和人为因素的影响,红树林的面积正快速减少,探寻保护和修复红树林的方法已迫在眉睫。文章以越南义安省沿海红树林为例,对红树林遭受破坏的原因、红树林保护现状、修复及保护工作难点等方面进行研究,从而提出有效可行的保护与修护方法。

关键词：红树林资源保护生态修复

Effect of Combinations of Sucrose and Cryoprotectants on the Survival of Catfish Embryos （Pangasidae hypophthamus）

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Journal of Agricultural Science and Technology(B) 2013年第12期3卷 887-892页

作者： Nguyen Thi Hong Nguyen Thi Nhung Nguyen Thi Uoc Nguyen Trung thanh Nguyen Thi Hiep Nguyen Van Hanh Pham Van Khanh Ha Thi ngoc Nga Truong Van Thuong Bui Xuan Nguyen Department of Embryo Biotechnology Institute of Biotechnology Vietnam Academy of Science and Technology 18-Hoang QuocViet Hanoi 8404 Vietnam Department of Environment and Pathology Research Institute for Aquaculture No. 2 Cai Be Tien Giang 8473 Vietnam Research Institute for Aquaculture No. 1 Dinh Bang Tu Son Bac Ninh 84241 Vietnam

Although cryopreservation of embryos has been used in most terrestrial animals, the application of this technique has not been succeeded for aquatic animals. In this study, the authors investigate the effect of different combinations of sucrose （SUC, C12H22OH） and cryoprotectants （CPAs） on the survival of the catfish embryos （Pangasidae hypophthalmus） at low temperatures （4, 0 and -20 ℃） for short-term storage. For this aim, embryos with somites and optic cups were exposed to different combinations of sucrose with methanol （SUC ＋ MeOH）, 1.2-propylene glycol （SUC ＋ PROH） and ethylene glycol （SUC ＋ EG） at four concentrations ratios：（1） 0.5 M SUC ＋ 0.5 M CPA; （2） 1 M SUC ＋ 0.5 M CPA; （3） 0.5 M SUC ＋ 1 M CPA; （4） 1 M SUC ＋ 1 M CPA for 40 min at 4, 0 and -20 ℃. Embryos kept in water at room temperature （RT）, 4, 0 and -20℃ were used as controls. The survival rate was expressed as a percentage of hatched embryos per total embryos treated. The results showed that the hatching rate declined significantly when embryos were stored in water at 0 ℃ and -20℃. For embryos at 0 ℃ storage, the highest survival rate （87.78%） was obtained with 1 M SUC ＋ 1 M MeOH combination while at -20 ℃, only embryos in the combined treatments of 0.5 M SUC ＋ 1 MEG and 0.5 M SUC ＋ 1 M PROH reached the hatching stage （40% and 83.33%, respectively）. In conclusion, the results showed that the catfish embryos are sensitive to sub-zero temperatures and the combined treatment of 0.5 M sucrose and 1 M propylene glycol can be used to protect catfish embryos from damages caused by low temperature （0 ℃ and -20 ℃）.

关键词： Catfish cryoprotectants embryos low temperature sucrose.

Applied Biofloc Technology for Target Species in the Mekong Delta in Vietnam： A Review

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Journal of Environmental Science and Engineering(B) 2017年第4期6卷 165-175页

作者： Nguyen Van Hoa Ta Van Phuong Tran ngoc Hai Chau Tai Tao Le Quoc Viet Nguyen Thi Hong Van Huynh thanh Toi Tran Huu Le Vo Nam Son Pham Quoc Anh Duy College of Aquaculture and Fisheries (CAF) Cantho University Cantho 270000-910000 Vietnam College of Applied Biology Tay Do University Cantho 270000-910000 Vietnam

BFT （Biofloc Technology） has been currently applied in Cantho University to a number of targeted species from fresh-to marine and saline water species in the Mekong Delta, e.g. striped catfish （Pangasianodon hypophthalmus）, white leg shrimp （Litopenaeus vannamei）, tiger shrimp （Penaeus monodon） and Artemia Vinhchau strain （Artemia franciscana） for both in the lab-scales or production scales. The best growth and survival rate of striped catfish was obtained in 6%o. For white leg shrimp, the results indicated：（1） C （Carbon） source e.g. rice-flour or molasses supplementary based on the feed provided to promote survival, growth and shrimp biomass harvested; （2） it was fed less than 20% as usual but showed similar to those in the control; （3） combination of rice-flour and molasses at a ratio of 70：30 by weight of C and N （Nitrogen） in a ration of 15：1 enhanced shrimp survival and growth; （4） in intensive culture, shrimp could be against the infection of disease and end up with higher survival, growth in earthen ponds. For tiger shrimp, a set up for larvae till post larvae at different ratios of C and N and C：N of 30 PLI5 displayed with better survival rate （49.73 ± 7.07%） and production （74,596 ± 10.608 PL/m3）. Artemiafranciscana was set up at C：N = 10：1 and salinities from 35, 60, 80 and 100 ppt. After two weeks, there were no significant difference among treatment and the control （without biofloc） in term of survival and growth. Moreover, total embryos per female was not significant different with the control and even the number of embryos as cysts tended to be higher. BFT displayed its advantages when applied on culture system of different targeted species and there is no doubt that it could help to sustain aquaculture and save environment in the Mekong Delta in near future.

关键词： Biofloc techology striped catfish white leg shrimp tiger shrimp Artemia Vinhchau strain.

越南柑橘砧木抗旱性及与其主要品种嫁接亲和性初步研究

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越南柑橘砧木抗旱性及与其主要品种嫁接亲和性初步研究

作者： NGUYEN ngoc HA（阮玉河）广西大学

学位级别：硕士

柑橘砧木能够多方面影响嫁接后柑橘品种的生长情况及抗逆性,包括柑橘的品质与产量,植株对环境适应性、接穗生长势等。同时,砧木对接穗的矿质营养代谢起着重要的作用,进一步影响其它的生理代谢活动,影响树体生长与开花结果。本研究选取... 详细信息

柑橘砧木能够多方面影响嫁接后柑橘品种的生长情况及抗逆性,包括柑橘的品质与产量,植株对环境适应性、接穗生长势等。同时,砧木对接穗的矿质营养代谢起着重要的作用,进一步影响其它的生理代谢活动,影响树体生长与开花结果。本研究选取越南安江省和龙安省的23种野生柑橘品种,分别设计田间和设施大棚两种栽培环境用于对比筛选抗旱品种,并各自设计处理组和对照组,其中,处理组进行干旱处理,对照组正常浇水。本实验通过研究了在干旱胁迫下不同柑橘品种的生长、生理指标的变化以及评估植株的旱害指数,并与抗旱砧木品种Carrizo枳橙对比,筛选抗旱能力较强的抗旱品种。对筛选出的优良砧木进行嫁接,嫁接6个月后,对植株的生长状况和砧穗亲合性进行评价。研究结果表明:1.干旱条件下,供试23种野生柑橘品种设施大棚栽培与田间栽培的生理指标变化大致相同,光化效率、叶片总叶绿素含量及淀粉含量转化下降;可溶性糖的总含量、叶片脯氨酸含量升高;树高的增长缓慢。筛选出5种与Carrizo枳橙生理指标最接近的野生柑橘,分别是thanhTra柚,DongNai酸柚,Do-2柚,Do-1柚,Truc。2.从成活率和接穗生长势方面来看,DongNai酸柚、thanhTra柚、Do-2柚、Do-1柚合适作为柚类的砧木,Truc不合适作为柚类的砧木。DongNai酸柚、thanh Tra柚、Do-2柚、Do-1柚以作为王柑橙的砧木成活率比较低,Truc合适作为王柑橙的砧木。

关键词：野生柑橘柑橘砧木干旱胁迫嫁接亲和性

Ecological and behavioural risk factors of scrub typhus in central Vietnam:a case-control study

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Infectious Diseases of Poverty 2021年第4期10卷 97-97页

作者： Hanh Thi Duc Tran Jan Hattendorf Hung Manh Do thanh Tien Hoang Hang Thi Hai Hoang Hoa ngoc Lam Mai Kim Huynh Lan Thi Hoang Vu Jakob Zinsstag Daniel Henry Paris Esther Schelling Department of Epidemiology and Public Health Swiss Tropical and Public Health InstituteBaselSwitzerland 不详

Background The risk factors for scrub typhus in Vietnam remain *** typhus caused by Orientia tsutsugamushi often presents as an undifferentiated febrile illness and remains under appreciated due to the limited availability of diagnostic *** tropical rickettsial illness is increasingly recognized as an important cause of non-malaria acute undifferentiated fever in *** study aimed to investigate behavioural and ecological related risk factors of scrub typhus to prevent this potentially life-threatening disease in *** We conducted a clinical hospital-based active surveillance study,and a retrospective residence-enrolment date-age-matched case–control study in Khanh Hoa province,Vietnam,from August 2018 to March *** examinations,polymerase chain reaction and enzyme-linked immunosorbent assay IgM tests were applied to define cases and *** enrolled participants filled out a questionnaire including demographic socio-economic status,personal behaviors/protective equipment,habitat connections,land use,and possible exposure to the *** conditional logistic regression was used to define the scrub typhus associated risk *** We identified 44 confirmed cases and matched them with 152 *** cases and controls,the largest age group was the 41–50 years old and males accounted for 61.4%and 42.8%,*** were similarities in demographic characteristics between the two groups,with the exception of *** factors were significantly associated with acquisition of scrub typhus,including sitting/laying directly on household floor[adjusted OR(aOR)=4.9,95%CI:1.6–15.1,P=0.006],household with poor sanitation/conditions(aOR=7.9,95%CI:1.9–32.9,P=0.005),workplace environment with risk(aOR=3.0,95%CI:1.2–7.6,P=0.020),always observing mice around home(aOR=3.7,95%CI:1.4–9.9,P=0.008),and use of personal protective equipment in the field(aOR=0.4,95%CI:0.1–1.1,P=0.076).Conclusions Ecological

关键词： Ecological Environmental Behaviour Risk factor Scrub typhus Orientia tsutsugamushi Vietnam

Effect of Yb^(3+) concentration on Er^(3+) luminescence properties of sol-gelderived silica-alumina xerogels

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Optoelectronics Letters 2006年第5期2卷 354-357页

作者： K.Tran ngoc H.Pham thanh C.Nguyen Duc C.Armellini A.Chiasera M.Ferrari Y.Jestin M.Montagna E.Moser S.Pelli G.C.Righini CNR-IFN Istituto di Fotonica e Nanotecnologie CSMFO groupvia Sommarie 14I-38050 PovoTrentoItaly ITIMS-Hanoi University of Technology No 1Dai Co VietHanoiVietnam Dipartimento di Fisica Università di TrentoCSMFO groupvia Sommarive 14I-38050 PovoTrentoItaly CNR-IFAC Nello Carrara Institute of Applied Physics Lab.of Optoelectronic TechnologiesVia Madonna del Piano 1050019 Sesto FiorentinoFirenzeItaly

Er^3- / Yb^3＋ co - doped silica - alumina monolithic xerogels were prepared with the same concentration on 2 000 Er/Si ppm and 6 000 AI/Si ppm. The Yb/Si content was varied from 0 to 4 000 ppm. Densification of the samples was achieved by thermal treatment in air at 950 ~C for 120 hours with a heating rate 0.1 ~C / min. Photoluminescence spectroscopy was used to obtain information about the effective excitation efficiency of Er^3＋ ions by co-doping with Yb^3- ions. The infrared-to-visible up-conversion luminescence has been investigated upon continuous wave excitation at 980 nm. The samples exhibit red, green and blue upconversion emission. It is found that the intensity of up-conversion luminescence increases with increasing Yb3- doping concentration. An opposite behavior is observed for the 4 I13/2 luminescence of the Er^3＋ ions.

关键词：铒离子二氧化硅干凝胶光致发光