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Using Isotope Technology for Surface Water Environment Research in Southern Hanoi

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Journal of Environmental Protection 2016年第8期7卷 1113-1118页

作者： Vo Thi Anh tran Khanh Minh Trinh Van Giap Ha lan Anh Nguyen Thanh Cong Nguyen Hong Thinh vu Hoai Institute for Nuclear Science and Technology Hanoi Vietnam Vinh University Vinh Vietnam

The surface water in the southern of Hanoi capital is researched by identifying δ2H and δ18O stable isotopes together with EC, DO, BOD5, COD, TSS. Surface water samples for studying include the Red river, Nhue river and Kim Nguu river, Thanh Nhan lake, Yen So lake and Van Quan lake were collected in the dry season (April) and the rainy season (August) in 2015. The stable isotope analysis results showed that the δ18O values is a range from -42.53‰ to -64.05‰ and, the δ2H values is the range from -5.09‰ to -8.79‰ under global meteoric waterline (in the water vapor region). The δ2H results of the rivers and lakes in the dry season are more negative than the rainy season with a small difference. The δ18O results of lakes in the dry season are more negative than the rainy season, but the δ18O results of river in the dry season are more positive than the rainy season. The results of the EC, BOD, COD, DO, TSS analysis showed that surface water environment has changed clearly in the two seasons and the contamination level in the dry season is usually higher than the rainy season. The lakes and rivers strongly influenced by human activities led to seriously pollution are Van Quan lake and Yen So lake, Nhue river and Kim Nguu river.

关键词： Isotope Technology Surface Water Quality Change in Difference Seasons

Study the Changes in Soil Organic Carbon of Rice-Maize Cropping System in the Top layer of Alluvisol Soil in Dan Phuong: A Study of C-13 Stable Isotope Composition (<i>δ</i><sup>13</sup>C)

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Journal of Environmental Protection 2019年第10期10卷 1361-1372页

作者： Nguyen Thi Hong Thinh vu Hoai Ha lan Anh Vo Thi Anh Truong Viet Chau Trinh Van Giap tran Minh Tien Isotope Hydrology laboratory Institute for Nuclear Science and TechnologyHanoiVietnam Soils and Fertilizers Research Institute HanoiVietnam

In this study, the experiments on field were conducted to examine the change in the content of soil organic carbon (SOC), its C-13 stable isotope composition (δ 13C) and some main physical, chemical parameters (soil moisture, pH, soil density, content of humic, fulvic, total N, total P, total K) in alluvial soil of Dan Phuong region—Vietnam at a depth of 0 - 30 cm when we changed the regime from 2 maize -1 rice crop to 2 rice - 1 maize crop per 1 year. In addition to analyzing the main parameters in soil, C content and its δ 13C value in parts of rice and maize (root, stem and leaf) were also analyzed to assess the contribution of plant residues on soil organic carbon content after harvest. The experiment was carried out in 2016-2017 on the field with the traditional farming method of local farmers along with the tropical monsoon weather conditions of the North-Vietnam. The results showed that SOC had positive correlation with total N, total P parameters and negative correlation with δ 13C values of soil samples at two layers (0 - 15 cm and 15 - 30 cm). The average of total dry biomass (stem, stump + roots and leaf parts) per 1 rice and 1 maize crop was 10.64 Mg/ha and 9.09 Mg/ha, respectively. The average of δ 13C value of rice (C3 plant) was -29.78‰ and its value of maize (C4 plant) was -12.61‰. The new plant (rice) contributes to the total soil organic carbon content from 11.31% to 44.14% at the 0 - 15 cm layer and from 6.55% to 11.31% at the 15 - 30 cm layer in one-year experiment period.

关键词： Soil Organic Carbon (SOC) C-13 Stable Isotope Maize and Rice Crop Soil Properties

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自适应语音压缩感知方法

东南大学学报（自然科学版） 2012年第6期42卷 1027-1030页

作者：罗武骏陶文凤左加阔赵力东南大学水声信号处理教育部重点实验室南京210096

针对固定正交基下语音信号稀疏化程度低、适应性差的问题,提出了一种自适应的语音稀疏化方法,并将其应用到语音压缩感知理论中.该方法首先采用线性预测系数的加权线性组合对语音信号进行线性预测,并以线性预测残差基作为信号基.然后,按... 详细信息

针对固定正交基下语音信号稀疏化程度低、适应性差的问题,提出了一种自适应的语音稀疏化方法,并将其应用到语音压缩感知理论中.该方法首先采用线性预测系数的加权线性组合对语音信号进行线性预测,并以线性预测残差基作为信号基.然后,按照稀疏约束条件训练出稀疏表示的过完备字典,并交替应用1-范数稀疏约束的追踪和奇异值分解算法,达到字典与稀疏系数同步更新.该方法从信号特征入手,学习并提取特征或纹理信息,能较好地实现语音信号的稀疏化,提高语音压缩感知的重构性能.实验结果显示,与其他正交基方法相比,该方法的语音稀疏化程度高.语音质量的主客观评价结果显示,该方法具有良好的重构性能.

关键词：压缩感知稀疏性语音线性预测

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DNA Sequence Classification by Convolutional Neural Network

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Journal of Biomedical Science and Engineering 2016年第5期9卷 280-286页

作者： Ngoc Giang Nguyen vu Anh tran Duc Luu Ngo Dau Phan Favorisen Rosyking Lumbanraja Mohammad Reza Faisal Bahriddin Abapihi Mamoru Kubo Kenji Satou Graduate School of Natural Science and Technology Kanazawa University Kanazawa Japan Institute of Science and Engineering Kanazawa University Kanazawa Japan

In recent years, a deep learning model called convolutional neural network with an ability of extracting features of high-level abstraction from minimum preprocessing data has been widely used. In this research, we proposed a new approach in classifying DNA sequences using the convolutional neural network while considering these sequences as text data. We used one-hot vectors to represent sequences as input to the model;therefore, it conserves the essential position information of each nucleotide in sequences. Using 12 DNA sequence datasets, we evaluated our proposed model and achieved significant improvements in all of these datasets. This result has shown a potential of using convolutional neural network for DNA sequence to solve other sequence problems in bioinformatics.

关键词： DNA Sequence Classification Deep Learning Convolutional Neural Network

军费预算减缩,对美国“转向”政策的信心亦减少

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英语文摘 2014年第5期 4-8页

作者： Khanh vu Duc Duvien tran 李凤芹

21世纪的美国军队将更加精简,这不是出于战略上的选择,而是财政上的无奈。美国新的防务预算的目标是将军人数量降至自二战前以来的最低水平。债台高筑的美国必须学着少花钱多办事,同时它在全球各地、包括亚洲在内的战略伙伴也必须要降... 详细信息

21世纪的美国军队将更加精简,这不是出于战略上的选择,而是财政上的无奈。美国新的防务预算的目标是将军人数量降至自二战前以来的最低水平。债台高筑的美国必须学着少花钱多办事,同时它在全球各地、包括亚洲在内的战略伙伴也必须要降低它们的期望值并增加自己所分担的责任。据关注国际安全问题的斯德哥尔摩国际和平研究所说,美国2012年将4.4%的国内生产总值用在国防上,比2009年和2010年保持的10年间最高水平——4.8%略有减少。即便在减少的情况下,军事开支仍然达到6890亿美元,约占联邦政府总预算的19%。根据新的预算方案,军费将

关键词：华盛顿 USS 西太平洋沿海作战

Deficiency of the transcription factor PlaG1 results in aberrant coiling and morphology of the epididymis

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Asian Journal of Andrology 2020年第4期22卷 342-347页

作者： Joanne Wong Almas R Juma Stephanie C tran Jemma G Gasperoni Sylvia V H Grommen Bert De Groef Department of Physiology Anatomy and MicrobiologyLa Trobe UniversityBundooraVictoria 3086Australia

Mice deficient in the transcription factor pleomorphic adenoma gene 1(PlaG1)exhibit reproductive issues that are characterized,in part,by decreased progressive sperm motility in the ***,the underlying cause of this impairment is *** epididymal transit is critical for sperm maturation and motility,the morphology of the epididymis of Plag1-deficient mice was investigated and the spatial expression patterns of PlaG1 protein and mRNA were *** X-gal staining and in situ hybridization,PlaG1 was shown to be widely expressed in both the epithelium and stroma in all regions of the mouse ***,the X-gal staining pattern was markedly different in the cauda,where it could be suggestive of PlaG1 secretion into the epididymal *** all ages investigated,the morphology of epididymides from Plag1 knockout(KO)mice was aberrant;the tubule failed to elongate and coil,particularly in the corpus and cauda,and the cauda was malformed,lacking its usual bulbous ***,the epididymides from Plag1 KO mice were significantly reduced in size relative to body *** 20%of Plag1-deficient mice,the left testicle and epididymis were *** impaired morphogenesis of the epididymal tubule is likely to be a major contributing factor to the fertility problems observed in male Plag1-deficient *** results also establish PlaG1 as an important regulator of male reproduction,not only through its involvement in testicular sperm production,but also via its role in the development and function of the epididymis.

关键词： development epididymis pleomorphic adenoma gene 1 tubule coiling Wolffian duct

Effects of the urban heat island and climate change on the growth of Khaya senegalensis in Hanoi,Vietnam

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Forest Ecosystems 2018年第4期5卷 516-529页

作者： Astrid Moser-Reischl Enno Uhl Thomas Rotzer Peter Biber tran van Con Nguyen Thanh Tan Hans Pretzsch Chair for Forest Growth and Yield Science Center of Life and Food Sciences WelhenstephanTechnical University MunichHans-Carl-von-Carlowitz-Platz 285354 FreisingGermany Vietnamese Academy of Forest Sciences Dong Ngac CommuneTu Liem DistrictHanoiVietnam Tay Nguyen University 567 Le Duan StreeBuon Ma Thuot CityDak La ProvinceVietnam

Background: Recent projections expect that Vietnam will be affected most severely by climate change with higher temperatures, more precipitation and rising sea levels. Especially increased temperatures will worsen the situations in cities, amplifying the urban heat island effect. Green infrastructures, i.e. urban trees are a common rtool to improve the urban micro-climate for humans. Vital and well growing trees provide greatest benefits such as evaporative cooling, shading, air filtering and carbon storage. However, urban tree growth is often negatively affected by urban growing conditions such as high soil sealing with compacted tree pits providing small growing spaces with limited water, nutrient and oxygen supply, further warm temperatures and high pollution emissions. This study analyzed the growth of urban and rural African mahogany(Khaya senegalensis(Desr.) A. Juss.) trees in the city of Hanoi, Vietnam and the effects of the surrounding climate conditions on tree ***: The results showed that rural African mahogany trees grew better than trees situated in the city center, which is contrary to other results on tree growth of temperate and subtropical cities worldwide. Moreover tree growth was similar regardless of the time of growth. Other results regarding stem growth of African mahogany located in different areas of Hanoi(east, west, north, city center) revealed a better growth in the northern and western outskirts of the city compared to the growth of trees in the city ***: African mahogany trees in the urban centers of Hanoi showed a decreased growth compared to rural trees,which was likely induced by a low ground-water level and high pollution rates. In view of climate change and global warming, the decreased tree growth in the city center may also affect tree service provision such as shading and cooling. Those climate mitigation solutions are strongly needed in areas severely affected by climate change and global warming such as

关键词： African mahogany Dendrochronology Ecosystem services Urban tree growth

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Influence of Process Factors on Electrode Wear Rate when EDM 90CrSi Steel using Graphite Electrodes

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Journal of Environmental Science and Engineering(B) 2023年第5期12卷 230-235页

作者： tran Huu Danh Le Thi Phuong Thao Nguyen Thi Quoc Dung vu Trung Tuyen Luu Anh Tung Vinh Long University of Technology Education Vinh Long City 85110Vietnam Thai Nguyen University of Technology Thai Nguyen city 251750Vietnam National Research Institute of Mechanical Engineering Hanoi City 511309Vietnam

The findings of a study on the optimization of Electric Discharge Machining(EDM)procedure for processing cylindrically shaped components with graphite electrodes are presented in this *** steel 90CrSi was the material of choice for the study’s ***,the Electrode Wear Rate(EWR)was chosen as the optimization problem’s objective *** experiment using the Taguchi design was conducted to address this ***,experiments were created and their outcomes were analyzed using the Minitab R19 *** impact of the input process factors on EWR was investigated,including the powder concentration,the pulse on and off times,the servo current,and the servo ***,the best process variables for a minimal EWR were provided.

关键词： EDM process factor EWR 90CrSi.

Effects of lime treatment on the microstructure and hydraulic conductivity of Héricourt clay

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Journal of Rock Mechanics and Geotechnical Engineering 2014年第5期6卷 399-404页

作者： Thanh Danh tran Yu-Jun Cui Anh Minh Tang Martine Audiguier Roger Cojean Mines ParisTech-Centre de Géosciences FontainebleauFrance laboratoire Navier/CERMES Ecole des Ponts ParisTech6 et 8 Avenue Blaise Pascal77455 Marne-la-Vallée Cedex 2France Mines ParisTeche-Centre de Géosciences FontainebleauFrance

This study aims at evidencing the effects of lime treatment on the microstructure and hydraulic conductivityof a compacted expansive clay, with emphasis put on the effect of lime hydration and *** this purpose, evolutions of hydraulic conductivity were investigated for both lime-treatedand untreated soil specimens over 7 d after full saturation of the specimens and their microstructureswere observed at the end. Note that for the treated specimen, dry clay powder was mixed with quicklimeprior to compaction in order to study the effect of lime hydration. It is observed that lime hydration andmodification did not affect the intra-aggregate pores but increased the inter-aggregates pores size. Thisincrease gave rise to an increase of hydraulic conductivity. More precisely, the hydraulic conductivity oflime-treated specimen increased progressively during the first 3 d of modification phase and stabilisedduring the next 4 d which correspond to a short period prior to the stabilisation phase. The microstructureobservation showed that stabilisation reactions took place after 7 d. Under the effect of stabilisation,a decreasing hydraulic conductivity can be expected in longer time due to the formation ofcementitious compounds. 2014 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved.

关键词： Clays Lime hydration Hydraulic conductivity Microstructure Temperature effect

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