检索结果-南通市图书馆

Minimizing Warpage for Macro-Size Fused Deposition Modeling Parts

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2021年第9期68卷 2913-2923页

作者： thanh Thuong Huynh Tien V.T.nguyen Quoc Manh nguyen Trieu Khoa nguyen Department of Mechanical Engineering Can Tho UniversityCampus IICan ThoVietnam Faculty of Mechanical Technology Industrial University of Ho Chi Minh CityHo Chi Minh70000Vietnam Mechanical Engineering Department National Kaohsiung University of Science and TechnologyKaohsiung80778Taiwan Faculty of Mechanical Engineering Hung Yen University of Technology and EducationHung Yen16000Vietnam

In this study,we investigated warpage and corner lifting minimization for three-dimensional printed parts generated by macro-size fused deposition modeling(FDM).First,the reasons for warpage were theoretically *** approach revealed that the thermal deformation and differential volumetric shrinkage of the extruded molten plastic resulted in warpage of FDM *** addition,low adhesion between the deposited model and the heated or non-heated printing bed may intensify warpage *** a next step,initial small-size and medium-size models were used to identify parameters to manage and minimize warpage in a way that would reduce material consumption and running ***,a macro-size model was built to experimentally investigate and verify the technical solutions to minimize the warpage of FDM *** conclusion,an improved part with reduced warpage was efficiently produced after detailed consideration of thermal effects and adhesion *** exists to widen the application scope of FDM technology in manufacturing for processes like thermoforming that involve mold core fabrication with *** technology,which has applications not only in mechanical engineering but also in related engineering fields,is convenient and could readily be applied to practical manufacturing industries.

关键词： Fused deposition modeling corner lifting volumetric shrinkage thermal deformation acrylonitrile butadiene styrene filament

An IoT-Cloud Based Intelligent Computer-Aided Diagnosis of Diabetic Retinopathy Stage Classification Using Deep Learning Approach

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2021年第2期66卷 1665-1680页

作者： K.Shankar Eswaran Perumal Mohamed Elhoseny Phong thanh nguyen Department of Computer Applications Alagappa UniversityKaraikudi630001India Faculty of Computers and Information Mansoura UniversityMansoura35516Egypt Department of Project Management Ho Chi Minh City Open UniversityHo Chi Minh City7000000Vietnam

Diabetic retinopathy(DR)is a disease with an increasing prevalence and the major reason for blindness among working-age *** possibility of severe vision loss can be extensively reduced by timely diagnosis and *** automated screening for DR has been identified as an effective method for early DR detection,which can decrease the workload associated to manual grading as well as save diagnosis costs and *** studies have been carried out to develop automated detection and classification models for *** paper presents a new IoT and cloud-based deep learning for healthcare diagnosis of Diabetic Retinopathy(DR).The proposed model incorporates different processes namely data collection,preprocessing,segmentation,feature extraction and *** first,the IoT-based data collection process takes place where the patient wears a head mounted camera to capture the retinal fundus image and send to cloud ***,the contrast level of the input DR image gets increased in the preprocessing stage using Contrast Limited Adaptive Histogram Equalization(CLAHE)***,the preprocessed image is segmented using Adaptive Spatial Kernel distance measure-based Fuzzy C-Means clustering(ASKFCM)***,deep Convolution Neural Network(CNN)based Inception v4 model is applied as a feature extractor and the resulting feature vectors undergo classification in line with the Gaussian Naive Bayes(GNB)*** proposed model was tested using a benchmark DR MESSIDOR image dataset and the obtained results showcased superior performance of the proposed model over other such models compared in the study.

关键词： Deep learning classification GaussianNaive Bayes feature extraction diabetic retinopathy

Fuzzy Multi-Criteria Decision Making for Solar Power Plant Location Selection

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2022年第9期72卷 4853-4865页

作者： Thai Hoang Tuyet Nhi Chia-Nan Wang nguyen Van thanh Department of Industrial Engineering National Kaohsiung University of Science and Technology80778Taiwan Faculty of Commerce Van Lang UniversityHo Chi Minh CityVietnam

Vietnam is one of Southeast Asian countries with a rapid GDP growth rate,ranging from 6.5%to 7%annually,leading to an average increase in energy demand of 11%per *** demand creates many new opportunities in the energy industry,especially renewable energy,to ensure sustainable development in the future for the country with applications of solar energy growing at the present,and other opportunities to expand in the *** Vietnam,thanks to favorable weather,climate,terrain characteristics and many preferential support policies,there are many great opportunities in the field of solar energy exploitation and *** selection is an important problem in all renewable energy ***,the author proposed a fuzzy Multi-criteria Decision-Making Model(MCDM)model for solar power plant location selection in this study,and as a result,location 5 is the optimal *** contribution of this study is to propose a MCDM for solar power plant location selection in Vietnam under fuzzy environmental conditions.

关键词： Solar power multi-decision topsis fanp fuzzy theory

The Roles of Female Involvement and Risk Aversion in Open Access Publishing Patterns in Vietnamese Social Sciences and Humanities

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Data and Information Science 2022年第1期7卷 76-96页

作者： Minh-Hoang nguyen Huyen thanh thanh nguyen Manh-Toan Ho Tam-Tri Le Quan-Hoang Vuong Centre for Interdisciplinary Social Research Phenikaa UniversityYen Nghia WardHa Dong DistrictHanoi 100803Vietnam

Purpose:The open-access(OA)publishing model can help improve researchers’outreach,thanks to its accessibility and visibility to the ***,the presentation of female researchers can benefit from the O A publishing *** that,little is known about how gender affects OA ***,the current study explores the effects of female involvement and risk aversion on OA publishing patterns among Vietname se social sciences and ***/methodology/approach:The study employed Bayesian Mindsponge Framework(BMF)on a dataset of 3,122 Vietnamese social sciences and humanities(SS&H)publications during *** Mindsponge mechanism was specifically used to construct theoretical models,while Bayesian inference was utilized for fitting ***:The result showed a positive association between female participation and OA publishing ***,the positive effect of female involvement on OA publishing probability was negated by the high ratio of female researchers in a *** status was negatively associated with the JIF of the journal in which the publication was published,but the relationship was moderated by the involvement of a female researcher(s).The findings suggested that Vietnamese female researchers might be more likely to publish under the OA model in journals with high JIF for avoiding the risk of public *** limitations:The study could only provide evidence on the association between female involvement and OA publishing ***,whether to publish under OA terms is often determined by the first or corresponding authors,but not necessarily *** implications:Systematically coordinated actions are suggested to better support women and promote the OA movement in ***/value:The findings show the OA publishing patterns of female researchers in Vietnamese SS&H.

关键词： Open science Gender inequality Risk-aversion Vietnam Bayesian analysis

An Ontology-Based Question Answering System for University Admissions Advising

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Intelligent Automation & Soft Computing 2023年第4期36卷 601-616页

作者： Thi thanh Sang nguyen Dang Huu Trong Ho Ngoc Tram Anh nguyen School of Computer Science and Engineering International UniversityVNU-HCMCVietnam National UniversityHo Chi Minh CityVietnam

Question-Answer systems are now very popular and crucial to support human in automatically responding frequent questions in manyﬁ***,these systems depend on learning methods and training ***,it is necessary to prepare such a good dataset,but it is not an easy *** ontol-ogy-based domain knowledge base is able to help to reason semantic information and make effective answers given user *** study proposes a novel chatbot model involving ontology to generate efﬁcient responses automatically.A case study of admissions advising at the International University–VNU HCMC is taken into account in the proposed chatbot.A domain ontology is designed and built based on the domain knowledge of university admissions using Protégé.The Web user interface of the proposed chatbot system is developed as a prototype using *** includes a search engine reasoning the ontology and generat-ing answers to users’*** experiments are carried out to test how the system reacts to different ***ﬁrst experiment examines questions made from some templates,and the second one examines normal questions taken from frequent *** results have shown that the ontology-based chatbot can release meaningful and long *** results are analysed to prove the proposed chatbot is usable and promising.

关键词： Ontology chatbots answer-question systems domain knowledge base admissions advising

Supplier Selection Fuzzy Model in Supply Chain Management:Vietnamese Cafe Industry Case

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2022年第8期72卷 2291-2304页

作者： Chia-Nan Wang Hoang Tuyet Nhi Thai nguyen Van thanh Department of Industrial Engineering and Management National Kaohsiung University of Science and Technology80778Taiwan Faculty of Commerce Van Lang UniversityHo Chi Minh CityVietnam

Supplier selection is a vital part of the supply chain and is also a current issue that concerns businesses today as supplier quality directly affects the operations of the *** the right supplier can help businesses increase productivity,competitiveness in the market,and profits without having to lower the quality of the ***,choosing a supplier is not a simple matter,it requires businesses to consider many aspects about their ***,the goal of this study is to propose an integrated model consisting of two models:Fuzzy Analytics Network Process(Fuzzy-ANP)model and Weighted Aggregated Sum Product Assessment(WASPAS)to solve the problem *** Fuzzy-ANP model was developed to evaluate the weightings of the supplier selection criteria,and the WASPAS Model was used to rank the *** example of supplier selection in the coffee industry in Vietnam was studied to validate the model,namely 5 main criteria,with 16 sub-criteria,and 7 *** model test results show that the Fuzzy ANP and WASPAS integration model was *** future,these developing models can apply to other industries or integrate with other models.

关键词： Fuzzy-ANP WASPAS multi-decision caféindustry supplier selection supply chain management

Carboxymethyl starch cross-linked by electron beam radiation in presence of acrylic acid sensitizer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2013年第B12期24卷 19-22页

作者： Doan Binh nguyen thanh Duoc Pham Thi Thu Hong R & D Center for Radiation Technology Vietnam Atomic Energy Institute 202A St. 11 Linh Xuan Ward Thu Duc District Ho Chi Minh City Vietnam

Carboxymethyl starch (CMS) can be cross-linked by electron beam radiation to form a biocompatible and environment-friendly hydrogel at a high absorbed dose and a condensed CMS concentration. Acrylic acid (AAc) can be used as a sensitizer in order to reduce the absorbed doses to an acceptable certain level. At an absorbed dose of 3-4 kGy, the gel content of crosslinked CMS can be obtained about 50% with 5% (w/w) AAc concentration used. The compressive strength of CMS samples increased with increasing their cross-linked densities due to raising absorbed doses. The swelling ratio of cross-linked CMS was also attainable at a maximum of 50 times in the distilled water. The enzymatic degradation of cross-linked CMS was carried out in acetate buffer pH 4.6 with 0.1% α-amylase enzymatic solution incubated at 40°C for 6 h. The crosslinked CMS samples were degraded slower than uncrosslinked CMS ones. The results indicated that the highly cross-linked CMS was almost fully degradable when the enzymatic hydrolysis was performed during 6 h. The FT IR spectra of cross-linked CMS in the presence of AAc were examined to observe the carboxyl group of AAc in the structure of cross-linked CMS. The hydrophilic of cross-linked CMS surface was determined by a contact-angle analysis. © 2013, Science Press. All rights reserved.

关键词：交联密度羧甲基淀粉电子束辐射丙烯酸敏化剂 FT-IR光谱吸收剂量 CMS

Prevalence and risk factors associated with long COVID symptoms in children and adolescents in a southern province of Vietnam

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Medicine 2024年第3期17卷 119-128,I0001,I0002页

作者： Huynh Ngoc Linh nguyen The Tan Le Thi Minh Thu nguyen Tu Loan nguyen Thi To Uyen Le thanh Thao Trang Truong thanh Nam Doan Hoang Phu Faculty of Medicine Ca Mau Medical CollegeCa Mau 98000Vietnam Ca Mau Obstetrics and Pediatrics Hospital Ca Mau 98000Vietnam Faculty of Basic Science and Public Health Dong Thap Medical CollegeDong Thap 81000Vietnam Graduate University of Sciences and Technology Vietnam Academy of Science and TechnologyHa Noi 10000Vietnam Community Public Health Research Program School of Public HealthWalailak UniversityNakhon Si Thammarat 80160Thailand Faculty Public Health Can Tho University of Medicine and PharmacyCan Tho City 94000Vietnam Doctoral Program in Health Sciences College of Graduate StudiesWalailak UniversityNakhon Si Thammarat 80160Thailand

Objective:To investigate the prevalence and risk factors associated with long COVID symptoms among children and adolescents who have recovered from ***:This study applied a cross-sectional approach within community settings in a southern province of Vietnam.A structured questionnaire featuring socio-demographic information and common long COVID symptoms was *** correlation coefficients assessed associations among pairs of long COVID ***,multivariable logistic regression models were performed to investigate the risk factors of long COVID in recovered COVID-19 children and ***:Among 422 participants,39.3%reported long COVID symptoms,with a prevalence of 45.2%(SD=0.5)in children and 22.2%(SD=0.4)in *** symptoms reported were cough 34.6%(SD=0.5),fatigue 20.6%(SD=0.4),shortness of breath 10.9%(SD=0.3),and lack of appetite 6.6%(SD=0.3).Concerning risk factors of long COVID,a higher risk was observed among demographic groups,including girls(OR 1.25,95%CI 1.15-1.37;P<0.001,reference:boys),children compared to adolescents(OR 1.24,95%CI 1.12-1.37;P<0.001),overweight individuals(OR 1.14,95%CI 1.02-1.27;P=0.018,reference:healthy weight),and participants without any COVID-19 vaccination(OR 1.36,95%CI 1.20-1.54;P<0.001),or have received only one single dose(OR 1.35,95%CI 1.10-1.64;P=0.004)compared to those who have received two ***,patients with a COVID-19 treatment duration exceeding two weeks also had a higher risk of long COVID(OR 1.32,95%CI 1.09-1.60;P=0.003)than those who recovered less than seven ***:The insights from this study provide crucial guidance for predicting the factors associated with the occurrence of long COVID in pediatric patients,contributing to strategic interventions aimed at mitigating the long COVID risks among children and adolescents in Vietnam.

关键词： Long COVID Prevalence Risk factors Children Adolescent Vietnam

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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