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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

Adaptability Zoning for Salty-Tolerant Rice Varieties in Soc Trang Prefecture by Using GIS and Remote Sensing

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Journal of Geological Resource and Engineering 2016年第3期4卷 142-150页

作者： Tran Thanh Dan Tran Thi Ngoc Trinh vo quang minh Huynh Ngoc Van Department of Land Resources College of the Environment and Natural Resources Can Tho University Viet Nam Department of Science and Technology Graduate School of Engineering Nagasaki University Japan Center of Seed and Plant Soc Trang province Viet Nam

Soc Trang is one of coastal provinces in which rice land is relatively low and therefore under annual threat of saline intrusion and other climatic variabilities. It raises an urgent need to identify various rice varieties which are short-duration, highly adaptive to salinity penetration, floods and aluminium poisonous matters, as well as high productivity and quality. The research applies the GIS （Geo-Information System） and RS （Remote Sensing） techniques to accurately evaluate the adaptability of different salinity-tolerant rice varieties. We have used information from FAO （The Food and Agriculture Organization）, Maplnfo and ArcGIS to map different components separately that are overlapped and mixed together to build different maps indicating the adaptability of different rice varieties to salinity in different locations in Soc Trang. We have also identified various factors affecting the productivity of these rice varieties. Then, several salinity-resistent rice varieties have been piloted in different areas to figure out which varieties are most suitable for specific regions.

关键词： Adaptability salty-tolerant rice climate change remote sensing GIS.

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

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

The processed C-terminus of AvrRps4 effector suppresses plant immunity via targeting multiple WRKYs

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Journal of Integrative Plant Biology 2024年第8期66卷 1769-1787页

作者： quang-minh Nguyen Arya Bagus Boedi Iswanto Hobin Kang Jiyun Moon Kieu Anh Thi Phan Geon Hui Son Mi Chung Suh Eui-Hwan Chung Walter Gassmann Sang Hee Kim Division of Applied Life Science(BK21 Four Program) Plant Molecular Biology and Biotechnology Research CenterGyeongsang National UniversityJinju 52828Korea Department of Life Science Sogang UniversitySeoul 04107Korea Department of Plant Biotechnology Korea UniversitySeoul 02841Korea Division of Plant Science and Technology Christopher S.Bond Life Sciences Center and Interdisciplinary Plant GroupUniversity of MissouriColumbiaMissouri 65211USA Division of Life Science and Research Institute of Molecular Alchemy Gyeongsang National UniversityJinju 52828Korea

Pathogens generate and secrete effector proteins to the host plant cells during pathogenesis to promote virulence and *** the plant carries resistance(R)proteins that recognize pathogen effectors,effector-triggered immunity(ETI)is activated,resulting in a robust immune response and hypersensitive response(HR).The bipartite effector AvrRps4 from Pseudomonas syringae *** has been well studied in terms of avirulence *** planta,AvrRps4 is processed into two *** Cterminal fragment of AvrRps4(AvrRps4^(C))induces HR in turnip and is recognized by the paired resistance proteins AtRRS1/AtRPS4 in ***,we show that AvrRps4^(C)targets a group of Arabidopsis WRKY,including WRKY46,WRKY53,WRKY54,and WRKY70,to induce its virulence ***,AvrRps4^(C)suppresses the general binding and transcriptional activities of immune-positive regulator WRKY54 and WRKY54-mediated ***4^(C)interferes with WRKY54's binding activity to target gene SARD1 in vitro,suggesting WRKY54 is sequestered from the SARD1 promoter by AvrRps4^(C).Through the interaction of Avr Rps4^(C)with four WRKYs,AvrRps4 enhances the formation of homo-/heterotypic complexes of four WRKYs and sequesters them in the cytoplasm,thus inhibiting their function in plant ***,our results provide a detailed virulence mechanism of AvrRps4 through its C-terminus.

关键词： AvrRps4 bacterial effector effector-triggered immunity immune response suppression transcription factor WRKY

Prevalence, risk factors, and BRAF mutation of colorectal sessile serrated lesions among Vietnamese patients

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World Journal of Clinical Oncology 2024年第2期15卷 290-301页

作者： Nhu Thi Hanh Vu Huy minh Le Diem Thi-Ngoc vo Hoang Anh Vu Nhan quang Le Dung Dang Quy Ho Duc Trong Quach Department of Internal Medicine University of Medicine and Pharmacy at Ho Chi Minh CityHo Chi Minh 700000Viet Nam GI Endoscopy Department University Medical Center at Ho Chi Minh CityHo Chi Minh 700000Viet Nam Department of Histology-Embryology and Pathology University of Medicine and Pharmacy at Ho Chi Minh CityHo Chi Minh 700000Viet Nam Center for Molecular Biomedicine University of Medicine and Pharmacy at Ho Chi Minh CityHo Chi Minh 700000Viet Nam Department of Endoscopy Cho Ray HospitalHo Chi Minh 700000Viet Nam

BACKGROUND Sessile serrated lesions(SSLs)are considered precancerous colorectal lesions that should be detected and removed to prevent colorectal *** studies in Vietnam mainly investigated the adenoma pathway,with limited data on the serrated *** To evaluate the prevalence,risk factors,and BRAF mutations of SSLs in the Vietnamese *** This is a cross-sectional study conducted on patients with lower gastrointestinal symptoms who underwent colonoscopy at a tertiary hospital in *** were diagnosed on histopathology according to the 2019 World Health Organi-zation *** mutation analysis was performed using the Sanger DNA sequencing *** multivariate logistic regression model was used to determine SSL-associated *** There were 2489 patients,with a mean age of 52.1±13.1 and a female-to-male ratio of 1:*** prevalence of SSLs was 4.2%[95%confidence interval(CI):3.5-5.1].In the multivariate analysis,factors significantly associated with SSLs were age≥40[odds ratio(OR):3.303;95%CI:1.607-6.790],male sex(OR:2.032;95%CI:1.204-3.429),diabetes mellitus(OR:2.721;95%CI:1.551-4.772),and hypertension(OR:1.650,95%CI:1.045-2.605).The rate of BRAF mutations in SSLs was 35.5%.CONCLUSION The prevalence of SSLs was 4.2%.BRAF mutations were present in one-third of *** risk factors for SSLs included age≥40,male sex,diabetes mellitus,and hypertension.

关键词： Colorectal cancer Sessile serrated lesion BRAF mutation Risk factors Diabetes mellitus Hypertension

Comparison of Treatment Efficacy of Different Number of Botulinum Toxin Type A Injection Sites for Crow’s Feet Lines: A Single-Center Retrospective Clinical Study in Vietnam

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International Journal of Dermatology and Venereology 2024年第3期7卷 131-136页

作者： minh Nguyen quang Mai Le Thi Hieu Duong Phuc Ha Vu Thai Doanh Le Huu Department of Stem Cell Research and Application National Hospital of Dermatology and VenereologyHanoi 100000Vietnam Department of Healthcare Activity Direction National Hospital of Dermatology and VenereologyHanoi 100000Vietnam Department of Dermatology Hanoi Medical UniversityHanoi 100000Vietnam

Objective:Botulinum toxin type A is frequently used to treat crow’s feet ***,the optimal dose and injection sites are still *** objective of this study was to compare the efficacy of different botulinum toxin type A injection patterns for the treatment of crow’s ***:This single-center,retrospective,clinical study was conducted at the National Hospital of Dermatology and Venereology from July 2020 to December *** on 60 patients with crow’s feet were collected and divided into 2 groups(3-or 4-point intramuscular injection)according to the intramuscular injection technique the patients *** treatment efficacy was assessed based on the changes in the Crow’s Feet Grading Scale score at 1,4,and 16 weeks after *** measures analysis of variance was used for the assessment of changes in scores over time between the two ***:After treatment,the average Crow’s Feet Grading Scale score was significantly decreased compared with the pretreatment score at all timepoints(1,4,and 16 weeks)in both states(dynamic:For 3-point intramuscular injection technique,1 week:1.90±0.71 vs.2.97±0.56;4 weeks:1.87±0.68 vs.2.97±0.56;16 weeks:2.60±0.67 vs.2.97±*** 4-point intramuscular injection technique,1 week:1.73±0.83 vs.3.03±0.49;4 weeks:1.73±0.74 vs.3.03±0.49;16 weeks:2.57±0.68 vs.3.03±0.49,all P<*** static:For 3-point intramuscular injection technique,1 week:1.20±0.89 vs.2.20±0.85;4 weeks:1.20±0.89 vs.2.20±0.85;16 weeks:1.87±0.97 vs.2.20±0.85;For 4-point intramuscular injection technique,1 week:1.50±0.86 vs.2.30±0.84;4 weeks:1.33±0.84 vs.2.30±0.84;16 weeks:1.87±0.97 vs.2.30±*** P<0.001).The average subjective patient-rated satisfaction scores after treatment were significantly higher in the 4-point injection group than in the 3-point injection group(P=0.028).The adverse events were post-injection bruising in 3 patients and a feeling of eyelid tightness in 3 ***:Botulinum toxin type A injecti

关键词： botulinum toxin type A crow’s feet lines injection site dose

Building the ARIMA Model for Forecasting the Production of Vietnam’s Coffee Export

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Journal of Applied Mathematics and Physics 2024年第4期12卷 1237-1246页

作者： Duy quang Phung Quoc Thang Trinh quang Truong Do Ngan Giang Nguyen Van Ha Nguyen Gia Khiem Ngo Thi minh Ngoc Tran Faculty of Technology and Data Science Foreign Trade University Hanoi Vietnam School of Economics and International Business Foreign Trade University Hanoi Vietnam

Coffee is a significant industry, accounting for 3% of Vietnam’s GDP, with annual export turnover consistently exceeding USD 3 billion. Despite global economic challenges affecting purchasing power at various times, Vietnam’s coffee exports in December 2023 continued to surge, reaching the highest level in the past 9 months at 190,000 tons, a 59.3% increase compared to November 2023, but still a slight 3.5% decrease from the same period last year. The export turnover reached USD 538 million, a 51% increase from November 2023 and a 26.4% increase from the same period last year. Therefore, forecasting the coffee export volume holds significant importance for coffee producers nationwide. This research employs the Box-Jenkins method to construct an ARIMA model for forecasting Vietnam’s coffee export volume based on annual data published by the General Statistics Office. Results indicate that among the models considered, the ARIMA(1, 1, 2) model is the most suitable. The study also provides short-term forecasts for Vietnam’s coffee export volume. However, the current model is limited to forecasting and is not yet optimized, as the assumed linearity in the model is a simplification.

关键词： ARIMA Forecasting Coffee Export volume Data Science