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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

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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

Generating highly active oxide-phosphide heterostructure through interfacial engineering to break the energy scaling relation toward urea-assisted natural seawater electrolysis

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Journal of Energy Chemistry 2024年第10期97卷 687-699页

作者： Ngoc quang tran Nam Hoang Vu Jianmin Yu Khanh Vy Pham Nguyen Thuy Tien Nguyen tran Thuy-Kieu Truong Lishan Peng Thi Anh Le Yoshiyuki Kawazoe Center for Innovative Materials and Architectures Vietnam National University Faculty of Materials Science and Technology University of Science Key Laboratory of Rare Earths Ganjiang Innovation Academy Chinese Academy of Sciences Department of Mechanical Engineering Hanbat National University (HBNU) School of Chemical Engineering-Hanoi University of Science and Technology New Industry Creation Hatchery Center Tohoku University

Urea-assisted natural seawater electrolysis is an emerging technology that is effective for grid-scale carbon-neutral hydrogen mass production yet *** scaling relations is an effective strategy to break through the bottleneck of natural seawater ***,by DFT calculation,we demonstrated that the interface boundaries between Ni2P and MoO2play an essential role in the selfrelaxation of the Ni-O interfacial bond,effectively modulating a coordination number of intermediates to control independently their adsorption-free energy,thus circumventing the adsorption-energy scaling *** this conceptual model,a well-defined 3D F-doped Ni2P-MoO2heterostructure microrod array was rationally designed via an interfacial engineering strategy toward urea-assisted natural seawater *** a result,the F-Ni2P-MoO2exhibits eminently active and durable bifunctional catalysts for both HER and OER in acid,alkaline,and alkaline sea water-based *** in-situ analysis,we found that a thin amorphous layer of NiOOH,which is evolved from the Ni2P during anodic reaction,is real catalytic active sites for the OER and UOR ***,such electrode-assembled urea-assisted natural seawater electrolyzer requires low voltages of 1.29 and 1.75 V to drive 10 and600 mA cm-2and demonstrates superior durability by operating continuously for 100 h at 100 mA cm-2,beyond commercial Pt/C || RuO2and most previous reports.

关键词： Break scaling relationships Doping Interfacial engineering Natural seawater splitting Urea electrolysis

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An In-Depth Analysis of Road Fatal Crash Patterns and Discussions in Ho Chi Minh City

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Journal of Traffic and transportation Engineering 2024年第3期12卷 141-150页

作者： Vuong tran quang Faculty of Civil Engineering Campus in Ho Chi Minh CityUniversity of Transport and CommunicationsHo Chi MinhVietnam

Although there has been a slight decrease in road traffic crashes, fatalities, and injuries in recent years, HCMC (Ho Chi Minh City) will continue to encounter challenges in mitigating and preventing road crashes. This study analyzes road crash data from the past five years, obtained from the Road-Railway Police Bureau (PC08) and TSB (Traffic Safety Board) in HCMC. This analysis gives us valuable insights into road crash patterns, characteristics, and underlying causes. This comprehensive understanding serves as a scientific foundation for developing cohesive strategies and implementing targeted solutions to address road traffic safety issues more effectively in the future.

关键词： Traffic safety safety policies fatal crash patterns

Novel Soft ComputingModel for Predicting Blast-Induced Ground Vibration in Open-Pit Mines Based on the Bagging and Sibling of Extra Trees Models

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Computer Modeling in Engineering & Sciences 2023年第3期134卷 2227-2246页

作者： quang-Hieu tran Hoang Nguyen Xuan-Nam Bui Department of Surface Mining Mining FacultyHanoi University of Mining and GeologyHanoi100000Vietnam Innovations for Sustainable and Responsible Mining(ISRM)Research Group Hanoi University of Mining and GeologyHanoi100000Vietnam

This study considered and predicted blast-induced ground vibration(PPV)in open-pit mines using bagging and sibling techniques under the rigorous combination of machine learning ***,four machine learning algorithms,including support vector regression(SVR),extra trees(ExTree),K-nearest neighbors(KNN),and decision tree regression(DTR),were used as the base models for the purposes of combination and PPV initial *** bagging regressor(BA)was then applied to combine these base models with the efforts of variance reduction,overfitting elimination,and generating more robust predictive models,abbreviated as BA-ExTree,BAKNN,BA-SVR,and *** is emphasized that the ExTree model has not been considered for predicting blastinduced ground vibration before,and the bagging of ExTree is an innovation aiming to improve the accuracy of the inherently ExTree model,as *** addition,two empirical models(i.e.,USBM and Ambraseys)were also treated and compared with the bagging models to gain a comprehensive *** this aim,we collected 300 blasting events with different parameters at the Sin Quyen copper mine(Vietnam),and the produced PPV values were also *** were then compiled as the dataset to develop the PPV predictive *** results revealed that the bagging models provided better performance than the empirical models,except for the BA-DTR *** those,the BA-ExTree is the best model with the highest accuracy(i.e.,88.8%).Whereas,the empirical models only provided the accuracy from 73.6%–76%.The details of comparisons and assessments were also presented in this study.

关键词： Mine blasting blast-induced ground vibration environmentally friendly blasting peak particle velocity bagging extra trees

transparent, stretchable, and rapid-response humidity sensor for body-attachable wearable electronics

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Nano Research 2017年第6期10卷 2021-2033页

作者： tran quang Trung Le Thai Duy Subramanian Ramasundaram Nae-Eung Lee School of Advanced Materials Science & Engineering Sungkyunkwan University (SKKU) Suwon Kyunggi-do 16419 Republic of Korea Center for Water Resource Cycle Research Korea Institute of Science and Technology Hwarang-ro 14 gil Seongbuk-gu Seoul 02793 Republic of Korea SKKU Advanced Institute of Nanotechnology (SAINT) SKKU Suwon Kyunggi-do 16419 Republic of Korea Samsung Advanced Institute for Health Sciences & Technology (SAIHST) SKKU Suwon Kyunggi-do 16419 Republic of Korea

Stretchable and conformal humidity sensors that can be attached to the human body for continuously monitoring the humidity of the environment around the human body or the moisture level of the human skin can play an important role in electronic skin and personal healthcare applications. However, most stretchable humidity sensors are based on the geometric engineering of non-stretchable components and only a few detailed studies are available on stretchable humidity sensors under applied mechanical deformations. In this paper, we propose a transparent, stretchable humidity sensor with a simple fabrication process, having intrinsically stretchable components that provide high stretchability, sensitivity, and stability along with fast response and relaxation time. Composed of reduced graphene oxide-polyurethane composites and an elastomeric conductive electrode, this device exhibits impressive response and relaxation time as fast as 3.5 and 7 s, respectively. The responsivity and the response and relaxation time of the device in the presence of humidity remain almost unchanged under stretching up to a strain of 60% and after 10,000 stretching cycles at a 40% strain. Further, these stretchable humidity sensors can be easily and conformally attached to a finger for monitoring the humidity levels of the environment around the human body, wet objects, or human skin.

关键词： transparent stretchablehumidity sensor reduced graphene oxide wearable electronics body-attachable intrinsically stretchable components

Facile synthesis of FeFe2O4 magnetic nanomaterial for removing methylene blue from aqueous solution

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Progress in Natural Science:Materials International 2019年第6期29卷 648-654页

作者： Van-Phuc Dinh Ngoc Quyen tran Nguyen-Que-tran Le quang-Huy tran Trinh Duy Nguyen Gr EEN), Nguyen Tat Thanh University Van Tan Le Future Materials and Devices Laboratory Institute of Fundamental and Applied Sciences Duy Tan University Institute of Applied Materials Science VAST Graduate University of Science and Technology VAST Le Quy Don–LBT Highschool Bien Hoa City Dong Nai province Center of Excellence for Green Energy and Environmental Nanomaterials (CE Industrial University of Ho Chi Minh City

A facile and simple chemical precipitation method was utilized to synthesize FeFe2O4magnetic nanomaterial for removing methylene blue（MB） from aqueous solution. Characterizations of this material were examined by using XRD, SEM, FT-IR, TGA-DTG and BET methods. Factors affecting the uptake of methylene blue, including p H, adsorption time, and MB initial concentration were also studied. The measured data were fitted by using four isotherm models including Langmuir, Freundlich, Sips and Temkin. Results showed that the Sips model offers the best fit to the data. In addition, the monolayer MB adsorption capacity obtained from the Langmuir model was 42.35 mg g-1under the optimal conditions of p H = 10 and adsorption time = 80 min. In particular, the uptake of MB onto FeFe2O4magnetic nanomaterial obtained from the kinetic and mechanism studies of the adsorption was in good agreement with prediction of the pseudo-first-order model, whereas the electrostatic interaction was found to play a primary mechanism.

关键词： FeFe2O4 magnetic nanomaterial Adsorption Methylene blue Adsorption mechanism

Detection of Denial-of-service Attacks

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计算机工程 2002年第S1期28卷 86-91页

作者： Anh quang tran, ZHANG Qianli , LI Xing (Tsinghua University, Beijing 100084, China) Tsinghua University Beijing 100084 China

Denial-of-service (DOS) is a type of computer attack, which can essentially disable computers and networks. Resource consumption type of DOS attack could not be detected by the traditional misuse detection technique. This paper presents a new method of support vector mchine (SVM) to detect these attacks. We find that a DOS attack to a host is related to the activities within an impact data set of the host. The SVM method is used to classify the subsets of an impact data set to estimate its anomalism. The experiment result shows that this method can detect resource consumption type of DOS attacks, such as SYN-flood, Smurf and UDP-storm. A receiver operating characteristic curve is plotted to determine performance for any possible operating point of the DOS attacks detection.

关键词： Denial-of-service attack Support vector machine Intrusion detection Receiver operating characteristic

Traffic Conflict Technique Development for Traffic Safety Evaluation under Mixed Traffic Conditions of Developing Countries

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Journal of Traffic and transportation Engineering 2017年第4期5卷 228-235页

作者： tran quang Vuong University of transport and Communications Campus in Ho Chi Minh City Ho Chi Minh City Vietnam

In developing countries, the numbers of traffic accidents, injuries and fatalities are very high and tend to increase atsignalized intersections. For example, in Ho Chi Minh City （HCMC） of Vietnam, the number of accidents at signalized intersectionsaccounted for 45% of the total accidents at all the intersections. This fact leads to strong necessity for analyzing traffic safety atsignalized intersections. Nevertheless, the historical accident data in HCMC is not available for deep analysis, this study uses videocameras to capture and analyze conflicts that potentially lead to accidents using TCT （traffic conflict technique）. Conflict severityidentification is one of the most significant steps to evaluate traffic safety at signalized intersections using TCT. Six zones （seriousconflict, common conflict, non-conflict, highest potential serious conflict, potential serious conflict, and potential common conflict） areexplored in this study to clarify conflict severity. This result is based on being the cut off value between serious conflicts and commonconflicts, according to 85% cumulative frequency of TTC （time to collision） and CS （conflict speed） under 3,050 samples size whichwere observed at 10 signalized intersections during August-November, 2014. Such a deep understanding is a scientific basis to studyhow to apply TCT to evaluate traffic safety at signalized intersections under mixed traffic conditions.

关键词： Traffic conflict technique, traffic safety, signalized intersections, traffic conflict severity, mixed traffic condition.