检索结果-南通市图书馆

Assessment of the Irrigation Capacity during the Dry Season Using Remote Sensing and Geographical Information (Case Study in the Binh Thuan Province, Vietnam)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Geosciences 2015年第11期6卷 1214-1220页

作者： hien Thi Thu Le Thang nguyen Ngoc Luc Hens Institute of Geography Vietnam Academy of Science and Technology (IG/VAST) Hanoi Vietnam Flemish Institute for Technological Research (VITO) Antwerp Belgium

Today satellite system provides a main instrument supplying regular data on land inventory and monitoring of land use/land cover changes, in a timely manner. These data are keys to many applications in different sectors: environment, forestry, hydrology, irrigation, agriculture, geology, resource management and planning. Using Landsat image and change detection, this paper presents a method to extract changes of agricultural land, as the basis for the assessment and development of irrigation systems, which enhance production and protect land resources. During the period 1996-2014, the agricultural land in Binh Thuan decreased from 43.5% (in 1996) to 40.1% (February, 2014) of the total land surface in the province. However, the land area under cultivation tends to decrease rapidly, from 25.7% in 1996 to 14.0% in 2014. Combining the results of land use change and assessing the capacity of the irrigation systems show which areas are frequently irrigated versus those are not. This allows proposing irrigation development needs contributing to more production while protecting land resources.

关键词： Land Use Change Irrigation Landsat Vietnam

Patterns of hepatitis B virus exposure and associated predictors in Vietnam: A crosssectional study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Medicine 2020年第12期13卷 535-541页

作者： Minh C.Duong Phuc V.D.Le Oanh N.K.Pham hien D.T.Pham Toan B.nguyen Hai T.Phan School of Public Health and Community Medicine University of New South WalesSydneyNew South WalesAustralia MEDIC Medical Center Ho Chi Minh CityVietnam Hospital for Tropical Diseases Ho Chi Minh CityVietnam Pham Ngoc Thach University of Medicine Ho Chi Minh CityVietnam

Objective:To examine the magnitude of isolated anti-HBc and other HBV serological patterns and associated predictors among adults seeking general health check-up at a large health center in ***:All 564 outpatients seeking general health checkup between January 2016 and December 2016 were asked to undertake HBV surface antigen,surface antibody,IgG and IgM core antibody(anti-HBc total),platelet counts,and liver function *** administered questionnaire was used to collect information regarding demography,in-house sources of infection,lifestyle,health condition and treatment,and HBV ***:Male gender(P=0.043),age(P=0.000),living in urban areas(P=0.040),HBV vaccination status(P=0.033),and ALT(P=0.040) were associated with isolated *** infection was associated with HBV vaccination status(P=0.001),ALT levels(P=0.010),AST levels(P=0.020),and platelet counts(P=0.007).Past/resolved HBV infection was associated with AST levels(P=0.005),ALT levels(P=0.014),and age(P=0.000).Conclusions:Isolated anti-HBc is quite *** of isolated anti-HBc include male gender,living in rural areas,and HBV *** prevalence of isolated anti-HBc also increases with *** timely detect occult HBV infection and prevent transmission,anti-HBc testing should be included in the health check-up for high risk individuals and screening program where HBV nucleic acid test is not *** prevent transmission,clinicians need to pay more attention on those who are at risk of having isolated anti-HBc and closely follow-up patients with isolated anti-HBc and educate them about the prevention of HBV infection.

关键词： prevention seeking Vietnam

Combining Methods of Lyapunov for Exponential Stability of Linear Dynamic Systems on Time Scales

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Applied Mathematics 2014年第21期5卷 3452-3459页

作者： nguyen Ngoc Huy dang Dinh Chau Department of Mathematics Vietnam Water Resource University Hanoi Vietnam Department of Mathematics Vietnam National University of Science Hanoi Vietnam

Consider the linear dynamic equation on time scales (1) where , ,?is a rd-continuous function, T is a time scales. In this paper, we shall investigate some results for the exponential stability of the dynamic Equation... 详细信息

关键词： Time Scales Exponential Stability Linear Dynamic Equation

Viral co-infections among children with confirmed measles at hospitals in Hanoi,Vietnam,2014

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Medicine 2017年第2期10卷 164-167页

作者： Hang Le Khanh nguyen Loan Phuong Do Van Thanh Thi Trieu Son Vu nguyen Phuong Vu Mai Hoang hien Thi Pham Thanh Thi Le Huong Thi Thu Tran Cuong Duc Vuong Mai Thi Quynh Le National Institute of Hygiene and Epidemiology No 1-Yesrsin streetHanoiVietnam

Objective:To characterize viral co-infections among representative hospitalized measles cases during the 2014 Hanoi ***:Throat swabs were collected from 54 pediatric patients with confirmed measles,and molecular diagnostics performed for 10 additional viral respiratory pathogens(Influenza A/H1N1pdm09;A/H3N2 and influenza B;Parainfluenza 1,2,3;Respiratory Synctial Virus,RSV;human Metapneumovirus,hM PV;Adenovirus and Picornavirus).Results:Twenty-one cases(38.9%) showed evidence of infection with other respiratory viruses:15 samples contained measles plus one additional virus,and 6 samples contained measles plus 2 additional *** was detected as a predominant cause of co-infections(13 cases;24.1%),followed by RSV(6 cases;11.1%),A/H1N1pdm09(3 cases;5.6%),PIV3(3 cases;3.7%),Rhinovirus(3 cases;3.7%) and hM PV(1 case;1.96%).Conclusions:Viral co-infections identified from pediatric measles cases may have contributed to increased disease severity and high rate of fatal *** treatment of measles cases may require control of multiple viral respiratory pathogens.

关键词： Measles virus Respiratory viruses Co-infection

Assessment of Salinity Intrusion in the Red River under the Effect of Climate Change

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Civil Engineering and Architecture 2010年第6期4卷 21-26页

作者： Le Thu hien Pham Ngoc Quy nguyen Trung Viet Faculty of Hydrology and Water Resoul＂ces Water Resources University Vietnam. Water Resources University Vietnam Department of Academic Affairs Water Resources University Vietnam

This paper focuses on analysis of salinity distribution along Red River and its main branches to determine and limit effects of salinity intrusion under variable scenarios for outlet discharge from upstream reservoirs and the tidal magnitude under global climate change effects. The effect of outlet discharge from upstream reservoirs, which generates flow in droughty months, is considered as upstream input condition for salinity intrusion. The sea level rising phenomenon is represented by scenarios according to prediction of the Intergovernmental Panel on Climate Change （IPCC）. The lateral flow and the rainfall in dry season are neglected in the process of simulation. MIKE 11, ID river model software by DHI （Danish Hydraulic Institute）, is used to simulate the processes of salt water intrusion from the river mouths to the upstream of the river in consideration the effect of the Sea Level Rise phenomenon and the operation of existing reservoirs and those under construction. The results indicate that salinity intrusion length from river mouth depends on the estuary characteristics, discharges from upper reservoirs and tidal phases （low and high tides）. With the safe salinity concentration for agriculture and livestock is 4 psu, the study shows that the length of intruded salt in Red River is about 40km from the river mouth, in otherwise, the effect of salinity intrusion in Thai Binh river is negligible. The Sea Level Rise phenomenon has inconsiderable affects on salinity intrusion processes in Red River System. The influence of outlet discharges from upstream reservoirs has also negligible affects on prevent salinity intrusion from the sea. According to the results of the study, reasonable water resources utilization and appropriate reservoir operation approaches in the drought will be studied to protect the crop and aquaculture from salinity intrusion.

关键词： Red River salinity intrusion reservoir climate change.

Control of Nonlinear Systems with Output Tracking Error Constraints

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Measurement Science and Instrumentation 2010年第3期1卷 217-223页

作者： Khac Duc Do dang Binh nguyen Anh Duc nguyen School of Mechanical Engineering University of Western Australia WA 6009 Australia Rectoral Office Thainguyen University of Technology Thainguyen Vietnam Department of Electrical Engineering Thainguyen University of Technology Thainguyen Vietnam

A oanstructive method is presented to design controllers that force the output of nonlinear systems in a strict feedback form to track a bounded and sufficient smooth reference trajectory asymptotically. Under suitable condition with the initial output tracking error, the proposed controllers guarantee the output tracking error within a symmtric or an asymmetric pre-specified limit range, and boundedness of all signals of the closed loop system. A transformation is inmxuced to take care of the output tracking error constraint. Smooth and/or p -times differentiable step functions are propsed and incor- porated in the output tracking error transformation to overcome difficulties due to the asynxnetric limit range on the output tracking error. As a result, there are no switchings in the proposed controllers despite of the asymmnetric limit range.

关键词： nonlinear system output constraint backstepping Lyapunov method

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

辐射花粉授粉结合胚拯救诱导黄瓜单倍体研究

辐射花粉授粉结合胚拯救诱导黄瓜单倍体研究

作者： nguyen Hac hien（阮黑显）南京农业大学

学位级别：硕士

黄瓜(Cucumis sativus L.)是世界十大重要蔬菜作物之一,在世界各地广泛种植。然而,由于黄瓜的遗传基础狭窄,仅采用常规育种手段选育新品种不仅周期长、费工费时,而且效率很低,单倍体育种被育种家认为是缩短育种周期、提高选择效率、获... 详细信息

黄瓜(Cucumis sativus L.)是世界十大重要蔬菜作物之一,在世界各地广泛种植。然而,由于黄瓜的遗传基础狭窄,仅采用常规育种手段选育新品种不仅周期长、费工费时,而且效率很低,单倍体育种被育种家认为是缩短育种周期、提高选择效率、获得遗传材料和有用突变体的重要途径,因此越来越受到重视。辐射花粉授粉结合胚拯救是获得单倍体(haploid)和双单倍体(Double haploid, DH)的重要途径之一,利用辐射花粉授粉技术可快速获得纯系,进而加快育种进程。本文利用不同基因型黄瓜品种为试材,进行辐射花粉授粉诱导单倍体培养研究,以期优化辐射花粉授粉诱导单倍体的技术体系,获得单倍体再生植株,为黄瓜的倍性育种打下基础。具体结果如下： 1.在辐射花粉授粉诱导黄瓜单倍体研究中,亲本基因型及辐射剂量对植株再生率有极显著的影响。辐射剂量为150Gy条件下植株再生率分别为：5211(3.92%)>CC3(0.42%)>南抗1号(0.32%),单倍体再生率为5211(1.96%)>CC3(0.21%)>南抗1号(0.19%);辐射剂量为250Gy条件下植株再生率分别为：5211(1.64%)南抗1号>(0.15%)>CC3(0.11%),单倍体再生率为5211(1.64%)>南抗1号(0.15%)>CC3(0.11%),辐射剂量为350Gy条件下植株再生率分别为：CC3(0.15%)>南抗1号(0.08%);单倍体再生率为5211(0%)、南抗1号(0%)、CC3(0%)。说明5211经150Gy辐射花粉授粉刺激较易诱导获得单倍体,而南抗1号较难用辐射花粉授粉方法获得单倍体。通过对相同基因型、不同剂量的植株再生率比较,150Gy,总体上效果好于250Gy及350Gy。对相同剂量、不同基因型的植株再生率而言,经150Gy辐射花粉授粉处理的5211植株再生率最高,为3.92%,单倍体再生率为1.96%;南抗1号最低,其植株再生率为0.32%,单倍体再生率为0.19%。对不同剂量、不同基因型而言,低剂量(150Gy)对三种基因型的植株再生率影响较大,而经高剂量(350Gy)辐射的三种基因型的植株再生率都较低,5211未获得再生植株,而CC3植株再生率0.15%,南抗1号为0.08%。此外还发现,5211受剂量影响波动最大,对辐射花粉刺激敏感,南抗1号波动幅度最小,对辐射花粉刺激最不敏感。根据通径分析模型可知辐射剂量的效应比基因型大,说明辐射剂量是影响植株再生率的主要因素。 2.秋季辐射花粉授粉诱导单倍体效果较好,春季辐射花粉诱导单倍体的效果较秋季差一些,可能与春季辐射时花粉的保存方式不当有关,但仍然可以肯定只要栽培条件适合、辐射处理操作恰当,春秋两季进行辐射诱导单倍体都是可行的。

关键词：黄瓜辐射花粉授粉植株再生单倍体二倍体

Nonlinear Control of Magnetic Bearings

同方学位论文库评论

在线全文

同方学位论文库

学校读者我要写书评

暂无评论

Journal of Measurement Science and Instrumentation 2010年第1期1卷 10-16页

作者： Khac Duc Do dang Hoe nguyen Thanh Binh nguyen School of Mechanical Engineering University of Western Australia WA 6009 Australia Vice-Rectoral Office Thainguyen University of Technology Thainguyen Vietnam Dept. of Human Resource University ofThainguyen Thainguyen Vietnam

In this paper, recent results controling nonlinear systems with output tracking error constmints are applied to the design of new tracking controllers for magnetic bearings. The proposed controllers can force the rotor to track a bounded and sufficiently smooth reference trajectory asymptotically and guarantee non-contactedness betweea the rotor and the stator of the magnetic beadngs. Simulation results are included to illustrate the effectiveness of the propsed controllers.

关键词： nonlinear system output constraint bockstepping L yapunov method

Introduction to a Fuel Continuous Mixer for Marine Diesel Engines＇ Application

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Shipping and Ocean Engineering 2015年第4期5卷 159-165页

作者： dang Van Uy nguyen Dai An Tran The Nam Marine Engineering Department Vietnam Maritime University Haiphong City 180000 Vietnam

To use the renewable fuels for marine field is still very limited due to the need of newly developed technology, highly requested safety （for gas fuel） and high price of biodiesel. Therefore, with some advantages, such as： simple producing process, reasonable price and simple modification technology needed, the blended SVO （straight vegetable oil） is recommended as suitable fuel for the marine application. Even though, there are some disadvantages of the blended SVO, such as a weak stability, layer separation in low temperature and some others. In order to apply the blended SVO as alternative fuel for marine diesel engines without the mentioned disadvantages, the paper will introduce a method to design and produce a fuel continuous mixer to make a blended SVO （palm oil）.

关键词： Fuel continuous mixer blended SVO palm oil alternative fuel.