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Genetic diversity in two threatened species in Vietnam:Taxus chinensis and Taxus wallichiana

Journal of Forestry Research 2017年第2期28卷 265-272页

作者： Dinh Duy Vu Thi Tuyet Xuan bui Minh Tam Nguyen Dinh Giap Vu Minh Duc Nguyen van thang bui Xiaohua Huang Yi Zhang College of Forestry Northwest A&F UniversityYangling 712100ShaanxiPeople's Republic of China Vietnam National Museum of Nature Vietnam Academy of Science and Technology(VAST)18 Hoang Quoc VietCau GiayHanoiVietnam Institute of Ecology and Biological Resource(VAST) 18 Hoang Quoc VietCau GiayHanoiVietnam Institute of Natural Products Chemistry(VAST) 18 Hoang Quoc VietCau GiayHanoiVietnam Institute of Forest Biotechnology Vietnam Forestry UniversityXuan MaiChuong MyHanoiVietnam

Taxus chinensis and T. wallichiana in have been threatened in their distribution areas in recent decades because of their over-exploitation and reduction and destruction of native habitats. Determining the genetic diversity in populations of the two species will provide guidelines for their protection and preservation. Two hundred and fifteen trees from six populations of T. chinensis and150 sampled trees of T. wallichiana were sampled. Six microsatellite primer pairs selected from 16 primer pairs were used to investigate genetic variation at the population and species levels. Five yielded polymorphic alleles, and among the 13 putative alleles amplified, 11 were polymorphic（accounting for 76.33 %）.Shannon＇s information index（I） and percentage of polymorphic bands（PPB）（I = 0.202 and PPB = 67.22 % for T. chinensis; I = 0.217 and PPB = 65.03 % for T. wallichiana）. Both species had low levels of genetic diversity（mean Ho= 0.107, He= 0.121 for T. chinensis; Ho= 0.095, He= 0.109 for T. wallichiana）. Genetic differentiation among populations was higher（FST= 0.189） for T. chinensis and lower（0.156） for ***, indicating limited gene flow（Nm） among populations for T. chinensis（0.68） and T. wallichiana（0.65）.Variation among individuals of T. chinensis was 63.59 and73.12 % for T. wallichiana. Thus, the threatened status of the two conifers is related to a lack of genetic diversity. All populations are isolated in small forest remnants. An ex situ conservation site should be established with a new population for these species that comprises all the genetic groups for the best chance to improve their fitness under environmental stresses.

关键词： Taxus populations alleles polymorphic microsatellite Vietnam primer accounting putative destruction

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Static analysis of corrugated panels using homogenization models and a cell-based smoothed mindlin plate element (CS-MIN3)

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Frontiers of Structural and Civil Engineering 2019年第2期13卷 251-272页

作者： Nhan NGUYEN-MINH Nha TRAN-van thang bui-XUAN Trung NGUYEN-THOI Faculty of Applied Science Bach Khoa University (BKU)Ho Chi Minh CityVietnam Faculty of Mathematics and Computer Science Ho Chi Minh City University of Science (HCMUS)Ho Chi Minh CityVietnam Department of Mathematics L ouisiana State UniversityBaton RougeLA 70803USA Division of Computational Mathematics and Engineering Institute of Computational ScienceTon Due Thang UniversityHo Chi Minh CityVietnam Faculty of Civil Engineering Ton Due Thang UniversityHo Chi Minh CityVietnam

Homogenization is a promising approach to capture the behavior of complex structures like corrugated panels. It enables us to replace high-cost shell models with stiffness-equivalent orthotropic plate alternatives. Many homogenization models for corrugated panels of different shapes have been proposed. However, there is a lack of investigations for verifying their accuracy and reliability. In addition, in the recent trend of development of smoothed finite element methods, the cell-based smoothed three-node Mindlin plate element (CS-MIN3) based on the first-order shear deformation theory (FSDT) has been proposed and successfully applied to many analyses of plate and shell structures. Thus, this paper further extends the CS-MIN3 by integrating itself with homogenization models to give homogenization methods. In these methods, the equivalent extensional, bending, and transverse shear stiftriess components which constitute the equivalent orthotropic plate models are represented in explicit analytical expressions. Using the results of ANSYS and ABAQUS shell simulations as references, some numerical examples are conducted to verify the accuracy and reliability of the homogenization methods for static analyses of trapezoidally and sinusoidally corrugated panels.

关键词： homogenization corrugated panel asymptotic analysis smoothed finite element method (S-FEM) cell-based smoothed three-node Mindlin plate element (CS-MIN3)

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城乡空间差异对麻栎林土壤活性有机碳的影响

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南京林业大学学报（自然科学版） 2020年第4期44卷 151-158页

作者：范洪旺 bui van thang 陶晓管致玮许克福安徽农业大学林学与园林学院安徽合肥230036 越南林业大学第二分校林学系同奈省81000 安徽农业大学轻纺工程与艺术学院安徽合肥230036

【目的】了解城乡空间差异下森林土壤活性有机碳的动态变化和影响因素,为城市森林生态系统的碳循环研究提供数据支撑。【方法】以合肥市城乡空间差异3个森林公园为研究对象,研究城乡麻栎林0~10 cm和≥10~20 cm土层内土壤活性有机碳含量... 详细信息

【目的】了解城乡空间差异下森林土壤活性有机碳的动态变化和影响因素,为城市森林生态系统的碳循环研究提供数据支撑。【方法】以合肥市城乡空间差异3个森林公园为研究对象,研究城乡麻栎林0~10 cm和≥10~20 cm土层内土壤活性有机碳含量,探讨城乡空间差异对森林土壤有机碳的影响。【结果】城乡空间差异条件下,麻栎林土壤微生物量碳(MBC)和可溶性有机碳(DOC)含量差异显著(P乡村(99.94 mg/kg)>城郊(96.42 mg/kg),不同城乡空间森林表层土壤MBC和DOC含量比≥10~20 cm土层的高。森林土壤MBC具有明显的季节变化,最高值出现在秋季(10月),而土壤DOC未发现显著季节变化。相关分析表明,土壤MBC和DOC与土壤总有机碳(TOC)、全氮(TN)呈极显著相关(P<0.001),土壤DOC与pH呈极显著负相关。【结论】不同城乡空间环境因子与土壤养分共同作用导致了土壤活性有机碳时空格局的差异。

关键词：城乡空间微生物量碳(MBC) 可溶性有机碳(DOC) 麻栎林

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城市和郊区麻栎林土壤有机碳组分及管理指数变化特征

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江苏农业学报 2022年第2期38卷 369-376页

作者：许慧 bui van thang 范洪旺许克福陶晓徐小牛安徽农业大学林学与园林学院安徽合肥230036

为了解城郊差异背景下森林土壤有机碳及其组分、碳库管理指数差异,揭示城郊差异对森林土壤活性有机碳含量及其稳定性的影响机制,于2017年7月至2018年3月对安徽省合肥市城市蜀山国家森林公园与郊区紫蓬山国家森林公园麻栎(Quercus acutis... 详细信息

为了解城郊差异背景下森林土壤有机碳及其组分、碳库管理指数差异,揭示城郊差异对森林土壤活性有机碳含量及其稳定性的影响机制,于2017年7月至2018年3月对安徽省合肥市城市蜀山国家森林公园与郊区紫蓬山国家森林公园麻栎(Quercus acutissima)林土壤进行分季节采样,系统比较城市和郊区森林土壤总有机碳(SOC)含量及活性有机碳组分[易氧化碳(EOC)、颗粒有机碳(POC)]含量、全氮(TN)含量季节动态特征及碳库管理指数变化特征。结果显示,城区森林土壤SOC、TN、EOC、POC含量明显高于郊区森林土壤,且0~10 cm土层含量显著大于0~20 cm土层(P<0.05),在0~10 cm土层,城市森林土壤SOC、TN含量分别是郊区的1.67、1.45倍,10~20 cm土层城市森林土壤SOC、TN含量分别是郊区的1.95、1.68倍。EOC占SOC的比例表现为郊区大于城市,POC占SOC的比例表现为城市大于郊区;蜀山森林土壤EOC、POC含量有显著的季节变化(P<0.05),表现为夏季高,春秋低;土层深度及季节的交互作用对EOC、POC含量无显著影响;土壤TN、SOC和EOC、POC含量两两之间呈极显著(P<0.001)相关;与城市森林相比,郊区土壤碳氮比(C/N)较低;城市森林土壤碳库活度(A)低于郊区,土壤碳库指数(CPI)高于郊区。在本研究区域,城市森林土壤储存了较多的碳,碳库相对稳定,具有较强的固碳潜力。

关键词：城市化麻栎林土壤有机碳颗粒有机碳易氧化碳碳库管理指数

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限定固有频率约束下基于全面学习和相量粒子群的结构优化

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Acta Mechanica Sinica 2023年第4期39卷 44-56页

作者： Ei Cho Pyone Sawekchai Tangaramvong Thu Huynh van Linh van Hong bui 高伟 Center of Excellence in Applied Mechanics and Structures Department of Civil Engineering Chulalongkorn University Bangkok 10330 Thailand Division of Computational Mathematics and Engineering Institute for Computational Science Ton Duc Thang University Ho Chi Minh City Viet Nam Centre of Infrastructure Engineering and Safety School of Civil and Environmental Engineer The University of New South Wales Sydney NSW 2000 Australia

本文提出了全面学习和相量粒子群相结合的方法用于解决限定固有频率约束下的空间结构优化问题.通过将相量理论和全面学习策略相结合以提高粒子群算法的效率.在优化的过程中,一个所谓的相角采用了周期正弦和余弦函数给定义速度的关键参... 详细信息

本文提出了全面学习和相量粒子群相结合的方法用于解决限定固有频率约束下的空间结构优化问题.通过将相量理论和全面学习策略相结合以提高粒子群算法的效率.在优化的过程中,一个所谓的相角采用了周期正弦和余弦函数给定义速度的关键参数建模使得速度可以从所有粒子前一步的最佳位置中选取.这个方法不但实现了粒子们可以快速学习并且在少量的计算中进行了在作用力和固有频率约束下结构杆件的安全性评估和优化尺寸分布.提出的优化设计方法成功解决了一些工程应用结构的基准设计问题,这证明了本文方法相对于最新元启发方法的准确性和稳定性.

关键词：余弦函数固有频率最佳位置粒子群算法安全性评估空间结构优化相量参数建模

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Ecoregional variations of aboveground biomass and stand structure in evergreen broadleaved forests

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Journal of Forestry Research 2020年第5期31卷 1713-1722页

作者： Tran van Do Mamoru Yamamoto Osamu Kozan Vo Dai Hai Phung Dinh Trung Nguyen Toan thang Lai Thanh Hai Vu Thanh Nam Trieu Thai Hung Hoang van thang Tran Duc Manh Cao Chi Khiem Vu Tien Lam Nguyen Quang Hung Tran Hoang Quy Pham Quang Tuyen Trinh Ngoc Bon Nguyen Thi Thu Phuong Ninh Viet Khuong Nguyen van Tuan Dang Thi Hai Ha Tran Hai Long Dang van Thuyet Dang Thinh Trieu Nguyen van Thinh Tran Anh Hai Duong Quang Trung Nguyen van Bich Dinh Hai Dang Pham Tien Dung Nguyen Huy Hoang Le Thi Hanh Phan Minh Quang Nguyen Thi Thuy Huong Hoang Thanh Son Nguyen Thanh Son Nguyen Thi van Anh Nguyen Thi Hoai Anh Pham Dinh Sam Hoang Thi Nhung Hoang van Thanh Nguyen Huu Thinh Tran Hong van Ho Trung Luong bui Kieu Hung Research Institute for Sustainable Humanosphere Kyoto UniversityUjiKyotoJapan Silviculture Research Institute Vietnamese Academy of Forest SciencesNorth Tu LiemHanoiVietnam Center for Southeast Asian Studies Kyoto UniversityKyotoJapan Vietnamese Academy of Forest Sciences North Tu LiemHanoiVietnam Vietnam Administration of Forestry No.2 Ngoc HaBa DinhHanoiVietnam

Biotic and abiotic factors control aboveground biomass(AGB)and the structure of forest *** study analyses the variation of AGB and stand structure of evergreen broadleaved forests among six ecoregions of Vietnam.A data set of 1731-ha plots from 52 locations in undisturbed old-growth forests was *** results indicate that basal area and AGB are closely correlated with annual precipitation,but not with annual temperature,evaporation or hours of *** area and AGB are positively correlated with trees>30 cm *** areas surveyed(52.6%)in these old-growth forests had AGB of 100–200 Mg ha^-1;5.2%had AGB of 400–500 Mg ha^-1,and 0.6%had AGB of>800 Mg ha^-*** percent of the areas surveyed had stand densities of 300–600 ***^-1,and 64%had basal areas of 20–40 m^2 ha^-*** is an important factor influencing the AGB of old-growth,evergreen broadleaved forests in *** causing the loss of large-diameter trees(e.g.,>100 cm DBH)affects AGB but may not seriously affect stand density.

关键词： Aboveground biomass Carbon storage Climatic variables Ecoregion Edaphic variables Oldgrowth forest

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Induction of Anthracnose Disease Resistance on Chili Fruit by Treatment of Oligochitosan—Nanosilica Hybrid Material

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Agricultural Sciences 2017年第10期8卷 1105-1113页

作者： Pham Dinh Dzung Le Thanh Hung Le Si Ngoc Hoang Dac Hiet bui van Le Nguyen Tien thang Dang van Phu Nguyen Ngoc Duy Nguyen Quoc Hien Research and Development Center for Hi-Tech Agriculture Ho Chi Minh City Vietnam Graduate University of Science and Technology Vietnam Academy of Science and Technology Hanoi Vietnam University of Science Vietnam National University Ho Chi Minh City Vietnam Research and Development Center for Radiation Technology Vietnam Atomic Energy Institute Ho Chi Minh City Vietnam

Oligochitosan (OC) with molecular weight Mw of 5000 g/mol was prepared by gamma Co-60 ray irradiation of chitosan solution. Nanosilica (nSiO2) with the size of 10 - 30 nm was synthesized by calcination of acid treated rice husk. The mixture of 1% OC - 1% nSiO2 was prepared by dispersion of nSiO2 in OC solution. The morphology of nSiO2 in the mixture of OC-nSiO2 was measured from images of transmission electron microscopy (TEM). The effect of foliar application of the mixture of OC-nSiO2 on the induction of resistance against anthracnose disease caused by Colletotrichum gloeosporioides fungus on chili fruits was investigated. Results indicated that foliar application of OC-nSiO2 with the concentration of 60 mg/l - 60 mg/l was found to be as the optimal treatment that reduced the disease severity on chili fruits to 22.2% compared with 90.0% of the control. Thus, OC-nSiO2 hybrid material could be considered as an effective biotic elicitor to prevent anthracnose disease infection for chili fruits. Furthermore, the prepared OC-nSiO2 hybrid material can also be used as an environmentally friendly agrochemical product for sustainable development of agriculture.

关键词： Oligochitosan Nanosilica Chili Fruit Colletotrichum gloeosporioides Anthracnose

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Imperfect Channel State Information of AF and DF Energy Harvesting Cooperative Networks

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China Communications 2016年第10期13卷 11-19页

作者： Hoang-Sy NGUYEN Anh-Hoa bui Dinh-Thuan DO Miroslav VOZNAK Wireless Communications Research Group Faculty of Electrical and Electronics Engineering Ton Duc Thang UniversityHo Chi Minh City Vietnam Eastern International University Binh Duong Province Vietnam Faculty of Electrical Engineering and Computer Science Technical University of Ostrava17. Listopadu 15/2172 70833 Ostrava Czech Republic

Wireless information and powered transfer networks(WIPT) has recently been implemented in 5th generation wireless networks. In this paper, we consider half-duplex relaying system in which the energy constrained relay node collects energy via radio frequency(RF) signals from the surrounding resources. Regarding energy harvesting protocol, we propose power time switching-based relaying(PTSR) architecture for both amplify-and-forward(AF) and decode-and-forward(DF). Especially, we reveal the analytical expressions of achievable throughput, ergodic capacity and energy-efficient in case of imperfect channel state information(CSI) for both AF and DF network. Through numerical analysis, we analyse the throughput performance, energy-efficient and ergodic capacity for different parameters, including power splitting ratio and energy harvesting time. Moreover, we also depict the performance comparison between AF and DF network with perfect and imperfect CSI. The results in numerical analysis reveal that the result of AF relaying network is less significant than DF relaying network in the various scenarios.

关键词： amplify-and-forward decode-and-forward energy harvesting throughput channel state information(CSI)

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A Hybrid Deep Learning Approach for PM2.5 Concentration Prediction in Smart Environmental Monitoring

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Intelligent Automation & Soft Computing 2023年第6期36卷 3029-3041页

作者： Minh Thanh Vo Anh HVo Huong bui Tuong Le Faculty of Information Technology HUTECH UniversityHo Chi Minh CityVietnam Natural Language Processing and Knowledge Discovery Laboratory Faculty of Information TechnologyTon Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Computing Fundamentals FPT UniversityHo Chi Minh CityVietnam Laboratory for Artificial Intelligence Institute for Computational Science and Artificial IntelligenceVan Lang UniversityHo Chi Minh CityVietnam Faculty of Information Technology Van Lang UniversityHo Chi Minh CityVietnam

Nowadays,air pollution is a big environmental problem in develop-ing *** this problem,particulate matter 2.5(PM2.5)in the air is an air *** its concentration in the air is high in developing countries like Vietnam,it will harm everyone’s *** prediction of PM2.5 concentrations can help to make the correct decision in protecting the health of the *** study develops a hybrid deep learning approach named PM25-CBL model for PM2.5 concentration prediction in Ho Chi Minh City,***,this study analyzes the effects of variables on PM2.5 concentrations in Air Quality HCMC *** variables that affect the results will be selected for PM2.5 concentration ***,an efficient PM25-CBL model that integrates a convolutional neural network(CNN)andBidirectionalLongShort-TermMemory(Bi-LSTM)*** model consists of three following modules:CNN,Bi-LSTM,and Fully connected ***,this study conducts the experiment to compare the performance of our approach and several state-of-the-art deep learning models for time series prediction such as LSTM,Bi-LSTM,the combination of CNN and LSTM(CNN-LSTM),and *** empirical results confirm that PM25-CBL model outperforms other methods for Air Quality HCMC dataset in terms of several metrics including Mean Squared Error(MSE),Root Mean Squared Error(RMSE),Mean Absolute Error(MAE),and Mean Absolute Percentage Error(MAPE).

关键词： Time series prediction PM2.5 concentration prediction CNN Bi-LSTM network

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Predicting rock size distribution in mine blasting using various novel soft computing models based on meta-heuristics and machine learning algorithms

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Geoscience Frontiers 2021年第3期12卷 458-472页

作者： Chengyu Xie Hoang Nguyen Xuan-Nam bui Yosoon Choi Jian Zhou Thao Nguyen-Trang School of Environment and Resources Xiangtan UniversityXiangtan 411105China Institute of Research and Development Duy Tan UniversityDa Nang 550000Viet Nam Department of Surface Mining Mining FacultyHanoi University of Mining and Geology18 Pho VienDuc Thang wardBac Tu Liem districtHanoi 100000Viet Nam Center for Mining Electro-Mechanical researchHanoi University of Mining and Geology18 Pho VienDuc Thang wardBac Tu Liem districtHanoi 100000Viet Nam Department of Energy Resources Engineering Pukyong National UniversityBusan 48513Republic of Korea School of Resources and Safety Engineering Central South UniversityChangsha 410083HunanChina Division of Computational Mathematics and Engineering Institute for Computational ScienceTon Duc Thang UniversityHo Chi Minh City 700000Viet Nam Faculty of Mathematics and Statistics Ton Duc Thang UniversityHo Chi Minh City 700000Viet Nam

Blasting is well-known as an effective method for fragmenting or moving rock in open-pit *** evaluate the quality of blasting,the size of rock distribution is used as a critical criterion in blasting operations.A high percentage of oversized rocks generated by blasting operations can lead to economic and environmental ***,this study proposed four novel intelligent models to predict the size of rock distribution in mine blasting in order to optimize blasting parameters,as well as the efficiency of blasting operation in open ***,a nature-inspired algorithm(i.e.,firefly algorithm-FFA)and different machine learning algorithms(i.e.,gradient boosting machine(GBM),support vector machine(SVM),Gaussian process(GP),and artificial neural network(ANN))were combined for this aim,abbreviated as FFA-GBM,FFA-SVM,FFA-GP,and FFA-ANN,***,predicted results from the abovementioned models were compared with each other using three statistical indicators(e.g.,mean absolute error,root-mean-squared error,and correlation coefficient)and color intensity *** developing and simulating the size of rock in blasting operations,136 blasting events with their images were collected and analyzed by the Split-Desktop *** which,111 events were randomly selected for the development and optimization of the ***,the remaining 25 blasting events were applied to confirm the accuracy of the proposed ***,blast design parameters were regarded as input variables to predict the size of rock in blasting ***,the obtained results revealed that the FFA is a robust optimization algorithm for estimating rock fragmentation in bench *** the models developed in this study,FFA-GBM provided the highest accuracy in predicting the size of fragmented *** other techniques(i.e.,FFA-SVM,FFA-GP,and FFA-ANN)yielded lower computational stability and ***,the FFA-GBM model can be used as a powerful

关键词： Mine blasting Rock fragmentation Artificial intelligence Hybrid model Gradient boosting machine Meta-heuristic algorithm

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