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A comparative study on kinetics and dynamics of two dump truck lifting mechanisms using MATLAB simscape

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Theoretical & Applied Mechanics Letters 2024年第2期14卷 146-156页

作者： Thong Duc Hong Minh quang Pham Son Cong tran Lam quang tran Truong thanh Nguyen Faculty of transportation Engineering Ho Chi Minh City University of Technology(HCMUT)Ho Chi Minh City 700000Vietnam Vietnam National University Ho Chi Minh City(VNU-HCM) Ho Chi Minh City 700000Vietnam Industrial Maintenance Training Center Ho Chi Minh City University of Technology(HCMUT)Ho Chi Minh City 700000Vietnam

In this paper,two lifting mechanism models with opposing placements,which use the same hydraulic hoist model and have the same angle of 50°,have been *** mechanical and hydraulic simulation models are established using MATLAB Simscape to analyze their kinetics and dynamics in the lifting and holding *** simulation findings are compared to the analytical calculation results in the steady state,and both methods show good *** the early lifting stage,Model 1 produces greater force and discharges goods in the container faster than Model ***,Model 2 reaches a higher force and ejects goods from the container cleaner than its counterpart at the end lifting *** established simulation models can consider the effects of dynamic loads due to inertial moments and forces generated during the system *** is crucial in studying,designing,and optimizing the structure of hydraulic-mechanical systems.

关键词： Dump truck Lifting mechanism Hydraulic MATLAB Simscape Kinetic dynamic analysis

Prevalence and outcomes of neonates with severe COVID-19:An observational study at Children’s Hospital 1 in Ho Chi Minh City,Vietnam

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Asian Pacific Journal of Tropical Medicine 2024年第9期17卷 392-399,I0001页

作者： Phung Nguyen The Nguyen tran thanh Thuc Nguyen thanh Hung Ngo Ngoc quang Minh Dang Quoc Duy tran Minh Nhut Nguyen Hoang Dung tran Nguyen Ai Nuong Dinh Nguyen Cam Tu Department of Pediatrics University of Medicine and Pharmacy at Ho Chi Minh cityHo Chi Minh CityVietnam Children’s Hospital 1 Ho Chi Minh CityVietnam Pediatric Department School of MedicineVietnam National University Ho Chi Minh CityVietnam

Objective:To evaluate the impact of the severe COVID-19 pandemic on neonates and develop strategies to improve their ***:We conducted an observational cross-sectional study at Children's Hospital 1(CH1)from July 25,2021,to May 31,*** neonates who had fever or respiratory symptoms or were born from mothers with COVID-19 and had a positive RT-PCR SARS-CoV-2 result would be *** classified neonates with COVID-19 into 2 groups:mild/moderate and severe for *** between groups were analyzed using Fisher's exact test/Chi-square test for categorical variables and Student's t-test/Wilcoxon Rank Sum test for continuous ***:This study included 88 newborns who had positive RT-PCR SARS-CoV-2 *** severity COVID-19 rate among neonatal cases was found to be 13.6%(12/88),with a corresponding mortality rate of 1.1%(1/88).All severe cases showed lung abnormalities as evident on chest X-ray *** addition to respiratory symptoms,a higher incidence of gastrointestinal manifestations,such as vomiting and diarrhea,was observed in the severe group,indicating a compelling *** administration of anticoagulant and anti-inflammatory drugs in the study group resulted in a satisfactory outcome with no significant ***:The COVID-19 pandemic has had a substantial impact on the well-being of *** management of COVID-19 in this population presents significant challenges.

关键词： COVID-19 Neonate Anti-inflammatory Anticoagulant

A Multiplicative Seasonal ARIMA/GARCH Model in EVN Traffic Prediction

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International Journal of Communications, Network and System Sciences 2015年第4期8卷 43-49页

作者： quang thanh tran Zhihua Ma Hengchao Li Li Hao quang Khai Trinh Sichuan Provincial Key Laboratory of Information Coding and transmission Southwest Jiaotong University Chengdu China Beijing Branch of China United Network Communications Co. Ltd. Beijing China Telecommunication Department University of Transport and Communications Hanoi Vietnam

This paper highlights the statistical procedure used in developing models that have the ability of capturing and forecasting the traffic of mobile communication network operating in Vietnam. To build such models, we follow Box-Jenkins method to construct a multiplicative seasonal ARIMA model to represent the mean component using the past values of traffic, then incorporate a GARCH model to represent its volatility. The traffic is collected from EVN Telecom mobile communication network. Diagnostic tests and examination of forecast accuracy measures indicate that the multiplicative seasonal ARIMA/GARCH model, i.e. ARIMA (1, 0, 1) × (0, 1, 1)24/GARCH (1, 1) shows a good estimation when dealing with volatility clustering in the data series. This model can be considered to be a flexible model to capture well the characteristics of EVN traffic series and give reasonable forecasting results. Moreover, in such situations that the volatility is not necessary to be taken into account, i.e. short-term prediction, the multiplicative seasonal ARIMA/GARCH model still acts well with the GARCH parameters adjusted to GARCH (0, 0).

关键词： Traffic Prediction ARIMA GARCH Multiplicative Seasonal ARIMA/GARCH EViews

An Enhanced Ensemble-Based Long Short-Term Memory Approach for Traffic Volume Prediction

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Computers, Materials & Continua 2024年第3期78卷 3585-3602页

作者： Duy quang tran Huy Q.tran Minh Van Nguyen Faculty of Civil Engineering Nha Trang UniversityNha Trang650000Vietnam Robotics and Mechatronics Research Group Faculty of Engineering and TechnologyNguyen Tat Thanh UniversityHo Chi Minh City700000Vietnam Department of Civil Engineering Ho Chi Minh City University of Technology and EducationHo Chi Minh City700000Vietnam

With the advancement of artificial intelligence,traffic forecasting is gaining more and more interest in optimizing route planning and enhancing service *** volume is an influential parameter for planning and operating traffic *** study proposed an improved ensemble-based deep learning method to solve traffic volume prediction problems.A set of optimal hyperparameters is also applied for the suggested approach to improve the performance of the learning *** fusion of these methodologies aims to harness ensemble empirical mode decomposition’s capacity to discern complex traffic patterns and long short-term memory’s proficiency in learning temporal ***,a dataset for automatic vehicle identification is obtained and utilized in the preprocessing stage of the ensemble empirical mode decomposition *** second aspect involves predicting traffic volume using the long short-term memory ***,the study employs a trial-and-error approach to select a set of optimal hyperparameters,including the lookback window,the number of neurons in the hidden layers,and the gradient descent ***,the fusion of the obtained results leads to a final traffic volume *** experimental results show that the proposed method outperforms other benchmarks regarding various evaluation measures,including mean absolute error,root mean squared error,mean absolute percentage error,and *** achieved R-squared value reaches an impressive 98%,while the other evaluation indices surpass the *** findings highlight the accuracy of traffic pattern ***,this offers promising prospects for enhancing transportation management systems and urban infrastructure planning.

关键词： Ensemble empirical mode decomposition traffic volume prediction long short-term memory optimal hyperparameters deep learning

Machine learning based models for predicting compressive strength of geopolymer concrete

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1028-1049页

作者： quang-Huy LE Duy-Hung NGUYEN thanh SANG-TO Samir KHATIR Hoang LE-MINH Amir H.GANDOMI thanh CUONG-LE Center for Engineering Application and Technology Solutions Ho Chi Minh City Open UniversityHo Chi Minh 700000Vietnam Institute of Civil Engineering Ho Chi Minh City University of TransportHo Chi Minh 700000Vietnam Faculty of Engineering&Information Technology University of Technology SydneyUltimoNSW 2007Australia

Recently,great attention has been paid to geopolymer concrete due to its advantageous mechanical and environmentally friendly *** effort has been made in experimental studies to advance the understanding of geopolymer concrete,in which compressive strength is one of the most important *** facilitate engineering work on the material,an efficient predicting model is *** this study,three machine learning(ML)-based models,namely deep neural network(DNN),K-nearest neighbors(KNN),and support vector machines(SVM),are developed for forecasting the compressive strength of the geopolymer concrete.A total of 375 experimental samples are collected from the literature to build a database for the development of the predicting models.A careful procedure for data preprocessing is implemented,by which outliers are examined and removed from the database and input variables are standardized before feeding to the fitting *** standard K-fold cross-validation approach is applied for evaluating the performance of the models so that overfitting status is well managed,thus the generalizability of the models is *** effectiveness of the models is assessed via statistical metrics including root mean squared error(RMSE),mean absolute error(MAE),correlation coefficient(R),and the recently proposed performance index(PI).The basic mean square error(MSE)is used as the loss function to be minimized during the model fitting *** three ML-based models are successfully developed for estimating the compressive strength,for which good correlations between the predicted and the true values are obtained for DNN,KNN,and *** numerical results suggest that the DNN model generally outperforms the other two models.

关键词： geopolymer concrete compressive strength prediction machine-learning based model deep neural network K-nearest neighbor support vector machines

Comparative Chemical Research in Essential Oils from Six Apiaceae Species Growing in the Northern Region of Vietnam

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1677-1687页

作者： Nguyen quang Hung Nguyen thanh Tung Nguyen Phuong Hanh Chu Thi Thu Ha Nguyen Thi Nhung Nguyen Thai An Vu Xuan Giang Luong Van Hao Oleh Koshovyi Ain Raal Institute of Ecology and Biological Resources Vietnam Academy of Science and Technology(VAST)Cau GiayHa Noi100000Viet Nam Graduate University of Science and Technology Vietnam Academy of Science and Technology(VAST)Cau GiayHa Noi100000Viet Nam Department of Pharmacognosy Faculty of Pharmacognosy and Traditional MedicineHanoi University of PharmacyHoan KiemHa Noi100000Viet Nam Sa Pa Research Center of Medicinal Materials National Institute of Medicinal MaterialsDien Bien PhuSa PaLao Cai330000Viet Nam Institute of Pharmacy Faculty of MedicineUniversity of TartuTartu50411Estonia

Our study aimed to compare the essential oil(EO)concentration and composition of several Apiaceae species growing in the Northern region of *** yields of EOs from materials ranged from 0.03%(root EO of Angelica acutiloba and aerial parts EO of Heracleum bivittatum)-0.27%(leaf EO of Xyloselinum vietnamense).Gas chromatography-mass spectrometry(GC-MS)allowed the identiﬁcation of 74 components in the EOs of six Apiaceae species,making up 94.4%–100.0%of the *** EO from Angelica acutiloba,(Z)-ligustilide accounted for an extremely large proportion(94.9%).EO of Angelica pubescens was dominated by six character-istic components includingα-pinene(21.5%),β-phellandrene(18.1%),p-cymene(12.2%),3-methylnonane(8.7%),o-cymene(8.1%),and D-sylvestrene(6.2%).The EO from Cryptotaenia japonica was characterized by high amounts ofα-selinene(48.7%),β-selinene(23.7%),and trans-β-farnesene(5.4%).The EOs from leaves and stems of Xyloselinum vietnamense were characterized by high concentrations of sabinene(69.8%and 33.8%),4-terpineol(8.7%and 7.4%)andβ-pinene(4.0%and 6.5%)while EOs from aerial parts and root of Xylo-selinum leonidii comprise four characteristic monoterpenes includingα-pinene(28.2%and 52.8%),β-pinene(7.9%and 10.3%),β-phellandrene(7.6%and 15.3%),and sabinene(3.0%and 4.1%).Additionally,cryptone is also one of the major components in the EO of Xyloselinum leonidii(13.2%in the aerial parts oil and 2.8%in the root oil).In the EOs isolated from the aerial parts and root of Heracleum bivittatum,α-pinene(22.5%and 70.2%)andβ-pinene(43.2%and 20.0%)were the predominant *** appeared in the EO from aerial parts of Heracleum bivittatum with a relatively high concentration(13.5%)while bornyl acetate(5.1%)was also one of the main components in the EO from its aerial parts but was not detected in other Apiaceae species in the present *** databases help identify and control the quality of plant material studied from the family Apiaceae growing in Vietnam.

关键词： Apiaceae essential oil terpenoids gaschromatography-mass spectrometry

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越南杧果产业发展趋势预测与启示

中国南方果树 2024年第4期53卷 251-258,264页

作者：邓志新 VU thanh Hai 刘洋铭 PHAM quang Thang 西南林业大学绿色发展研究院昆明650224 越南国立农业大学越南河内云南机电职业技术学院昆明650201 越南有机农业工艺研究院越南河内

近年来,中国已成为越南杧果出口主要目标市场。本文以越南杧果产业为研究对象,运用“全程质量支撑技术体系”理论,分析其杧果产业发展现状及关键技术约束集,预测越南杧果产业发展趋势,推测其对中国杧果产业近期、中期、长期的影响,提出... 详细信息

近年来,中国已成为越南杧果出口主要目标市场。本文以越南杧果产业为研究对象,运用“全程质量支撑技术体系”理论,分析其杧果产业发展现状及关键技术约束集,预测越南杧果产业发展趋势,推测其对中国杧果产业近期、中期、长期的影响,提出我国应对策略建议,助力我国杧果产业发展。

关键词：越南杧果产业全程质量支撑技术体系中国大青杧

Effect of Freeze-Thaw and Urea in Solubility of GPC3-Csub Protein Expressed in Escherichia coli

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Journal of Biosciences and Medicines 2024年第4期12卷 288-297页

作者： Xuan-Truc Chu-Dao Kim-Tuyen Huynh-Dam Dang-Thuc Ngo-Luong quang-Luan Le thanh-Thao Vo-Nguyen Department of Medical Biotechnology Biotechnology Center of Ho Chi Minh City Ho Chi Minh City Vietnam

Glypican-3 is a protein encoded by the Glypican-3 gene located on human X chromosome (Xq26), composed of two subunits, a 40 kDa N-terminal subunit, and a 30 kDa C-terminal subunit. Glypican-3 is a currently potential target molecule for liver cancer treatments because of its over-expression and growth effects on hepatocellular carcinoma (HCC). This study examined the expression and purification of a C-terminal subunit of Glypican-3 protein (GPC3-Csub) due to its application in both diagnosis and therapy for hepatocellular carcinoma. The gene encoding for GPC3-Csub was successfully cloned into plasmid pET28a fused with an affinity tag composed of six consecutive histidine residues (His-tag). Recombinant protein GPC3-Csub was expressed in Escherichia coli BL21 (DE3) in the condition of adding 3% ethanol with IPTG induction. GPC3-Csub was extracted using repeated freeze-thaw cycles with lysozyme, and inclusion bodies were solubilized by 8M Urea, SDS 10% in pH 12. His-tag fused GPC3-Csub proteins allowed it to be purified by affinity chromatography method using the Nickel-nitrilotriacetic acid (Ni-NTA) column. High expression of GPC3-Csub was confirmed by Coomassie staining and western-blot. GPC3-Csub could be isolated with a Ni-NTA column and have a purity of about 90%.

关键词： Glypican-3 Affinity Chromatography Inclusion Body Liver Cancer

Marketing Strategies Evaluation and Selection for Supply Chain Management Under Uncertainty

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Computers, Materials & Continua 2022年第12期73卷 6535-6546页

作者： Ngo quang Trung Nguyen Van thanh Faculty of Commerce Van Lang UniversityHo Chi Minh City70000Vietnam

Sustainable marketing,often known as green marketing,has grown in popularity over the last two *** is currently putting pressure to encourage firms to become environmentally aware in multiple aspects like human and financial utilization,advertisement,and product *** types of companies are including many environmental campaigns into their own products to take advantage of the *** many scholars have addressed the relevance of green marketing as well as theory development,this study is unique in that it examines both techniques in a fuzzy *** integrated Fuzzy Multicriteria Decision Making Model(MCDM)of the analytical hierarchy process(AHP)and a Portuguese-acronymous MCDM method(TODIM)are used to select the best marketing strategy from five alternatives:(i)Green Design,(ii)Green Positioning,(iii)Green Pricing,(v)Green Packaging,and(iv)Green *** on criteria such as the scale of the green market,price parity,and the commitment of top *** for evaluating green marketing strategies was established in the study as contributions for decisionmakers in this field under unclarified *** research also a useful guideline for ranking alternatives in others industry.

关键词： Green marketing MCDM model sustainable marketing strategy