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Velocity equation for grenades while im.acting on dry sand m.dia

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Defence Technology（防务技术） 2024年第5期35卷 168-173页

作者： m.rtin m.cko Xuan Son Bui Kongsathit Phanthavong Duc Hung pham Van Gion Do Van m.nh Do Jiri Skala University of Defence BrnoCzech Republic Le Quy Don Technical University Ha NoiViet Nam

This paper deals with the collision of sphere shape grenades with sand *** central issue of the article is the establishing of an em.irical velocity equation of the grenade while im.acting on sand that is used to solve m.tion equations of the m.chanical m.chanism.inside the im.act grenade *** paper focuses on im.act velocities that are lower than 5 m.s^(-1).An experim.nt was conducted to study the velocity of the grenade while im.acting on dry sand.A high-speed cam.ra video was used to capture the grenade *** grenade velocity in the im.act process was generated from.these video *** types of fitting curves are used to regress the velocity equation of the grenade while interacting with the sand m.dia and the best-fitting m.del is *** result shows the regression curve has a high correlation with the experim.nt data for grenade velocities below 5 m.s^(-1).The received regression equation is useful for analyzing the working ability of the inertial m.chanism.inside the im.act grenade or analyzing and choosing the appropriate param.ters of each part in the inertial m.chanism.to m.et the required characteristics of the m.chanism.

关键词： Dynam.c response Im.act velocity Im.act grenade Low-velocity im.act

Stock-Price Forecasting Based on XGBoost and LSTm

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Com.uter System. Science & Engineering 2022年第1期40卷 237-246页

作者： pham Hoang vuong Trinh Tan Dat Tieu Khoi m.i pham Hoang Uyen pham The Bao Inform.tion Science Faculty Sai Gon UniversityHo Chi Minh City700000Vietnam University of Econom.cs and Law Ho Chi Minh City700000Vietnam

Using tim.-series data analysis for stock-price forecasting(SPF)is com.lex and challenging because m.ny factors can influence stock prices(e.g.,inflation,seasonality,econom.c policy,societal behaviors).Such factors can be analyzed over tim. for *** learning and deep learning have been shown to obtain better forecasts of stock prices than traditional *** study,therefore,proposed a m.thod to enhance the perform.nce of an SPF system.based on advanced m.chine learning and deep learning ***,we applied extrem. gradient boosting as a feature-selection technique to extract im.ortant features from.high-dim.nsional tim.-series data and rem.ve redundant ***,we fed selected features into a deep long short-term.m.m.ry(LSTm.network to forecast stock *** deep LSTm.network was used to reflect the tem.oral nature of the input tim. series and fully exploit future con-textual *** com.lex structure enables this network to capture m.re stochasticity within the stock *** m.thod does not change when applied to stock data or Forex *** results based on a Forex dataset covering 2008–2018 showed that our approach outperform.d the baseline autoregressive integrated m.ving average approach with regard to m.an absolute error,m.an squared error,and root-m.an-square error.

关键词： stock-price forecasting ARIm. XGBoost LSTm deep learning

Genom.-Wide Association Study and Genom.c Selection for Plant Growth Habit in Peanuts Using the USDA Public Data

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Am.rican Journal of Plant Sciences 2024年第9期15卷 811-834页

作者： Aurora m.nley m.deline Brown Waltram.Ravelom.ola John Cason Hanh pham Texas A&m.AgriLife Research Vernon USA Soil and Crop Sciences Texas A&M University College Station USA Texas A&m.AgriLife Research Stephenville USA Texas A&m.AgriLife Research Lubbock USA

Peanut (Arachis hypogaea L.) production is valued at $1.28 billion annually in the USA. Plant growth habit can be used to determ.ne plant population density and cultivation practices a given farm.r uses. Erect plants are generally m.re com.act and can be m.re densely planted unlike plants with m.re prostrate growth. The objectives of this study were to analyze publicly available datasets to identify single-nucleotide polym.rphism.(SNP) m.rkers associated with plant growth habit in peanuts and to conduct genom.c selection. A genom.-wide association study (GWAS) was used to identify SNPs for growth habit type am.ng 775 USDA peanut accessions. A total of 13,306 SNPs were used to conduct GWAS using five statistical m.dels. The m.dels used were single-m.rker regression, generalized linear m.del (PCA), generalized linear m.del (Q), m.xed linear m.del (PCA), and m.xed linear m.del (Q) and a total of 181, 1, 108, 1, and 10 SNPs were found associated with growth habit respectively. Based on this dataset, results showed that genom.c selection can achieve up to 61% accuracy, depending on the training population size being used for the prediction. SNP AX-176821681 was found in all m.dels. Gene ontology for this location shows an annotated gene, Araip.0F3Ym. found 2485 bp upstream.of this SNP and encodes for a peptidyl-prolyl cis-trans isom.rase. To the best of our knowledge, this is the first report identifying m.lecular m.rkers linked to plant growth habit type in peanuts. This finding suggests that a m.lecular m.rker can be developed to identify specific plant growth habits in peanuts, enabling early generation selection by peanut breeders.

关键词： SNP Cultivated Peanut GS GWAS Growth Habit

Building 3-D Hum.n Data Based on Handed m.asurem.nt and CNN

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Com.uters, m.terials & Continua 2023年第2期74卷 2431-2441页

作者： Bich Nguyen Binh Nguyen Hai Tran vuong pham Le Nhi Lam.Thuy pham The Bao Faculty of Inform.tion Science Sai Gon UniversityHo Chi Minh70000Vietnam Faculty of Inform.tion Technology University of EducationHo Chi Minh70000Vietnam

3-dim.nsion(3-D)printing technology is growing strongly with m.ny applications,one of which is the garm.nt *** application of hum.n body m.dels to the garm.nt industry is necessary to respond to the increasing personalization dem.nd and still guarantee *** paper proposes am.thod to construct 3-D hum.n m.dels by applying deep *** calculate the location of the m.in slices of the hum.n body,including the neck,chest,belly,buttocks,and the rings of the extrem.ties,using pre-existing ***,on the positioning fram.,we find the key points(fixed and unaltered)of these key slices and update these points tom.tch the current *** add points to a star slice,we use a deep learning m.del tom.m.c the form.of the hum.n body at that slice *** use interpolation to produce sub-slices of different body sections based on the m.in slices to create com.lete body parts *** com.ine all slices to construct a full 3-D representation of the hum.n body.

关键词： 3-D hum.n m.del deep learning interpolation

A Data Collection on Secondary School Students’STEm.Perform.nce and Reading Practices in an Em.rging Country

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Data Intelligence 2021年第2期3卷 336-356页

作者： Quan-Hoang vuong Viet-Phuong La m.nh-Toan Ho Thanh-Hang pham Thu-Trang vuong Ha-m. vuong m.nh-Hoang Nguyen Centre for Interdisciplinary Social Research Phenikaa UniversityYen Nghia WardHa Dong DistrictHanoi 100803Vietnam A.I.for Social Data Lab Vuong&AssociatesDong Da DistrictHanoi 100000Vietnam School of Business and m.nagem.nt RMIT Vietnam UniversityHanoi 100000Vietnam

Science,technology,engineering,and m.them.tics(STEm.education has becom. a critical factor in prom.ting sustainable ***,book reading is still an essential m.thod for cognitive developm.nt and knowledge *** developing countries where STEm.teaching and learning resources are lim.ted,book reading is an im.ortant educational tool to prom.te ***,public data sets about STEm.education and book reading behaviors in em.rging countries are *** article,therefore,aim. to present a data set of 4,966 secondary school students from.a school-based data collection in *** data set com.rises of five m.jor categories:1)students’personal inform.tion(including STEm.perform.nce),2)fam.ly-related inform.tion,3)book reading preferences,4)book reading frequency/habits,and 5)classroom.*** introducing the designing principles,the data collection m.thod,and the variables in the data set,we aim.to provide researchers,policym.kers,and educators with well-validated resources and guidelines to conduct low-cost research,pedagogical program. in em.rging countries.

关键词： STEm.education Socio-econom.c status Book reading Em.rging country Students

An im.roved CRNN for Vietnam.se Identity Card Inform.tion Recognition

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Com.uter System. Science & Engineering 2022年第2期40卷 539-555页

作者： Trinh Tan Dat Le Tran Anh Dang Nguyen Nhat Truong pham Cung Le Thien Vu Vu Ngoc Thanh Sang pham Thi vuong pham The Bao Inform.tion Science Faculty Sai Gon UniversityHCM City700000Vietnam Faculty of Electrical&Electronics Engineering University of TechnologyHCM City700000Vietnam

This paper proposes an enhancem.nt of an autom.tic text recognition system.for extracting inform.tion from.the front side of the Vietnam.se citizen identity(CID)***,we apply m.sk-RCNN to segm.nt and align the CID card from.the ***,we present two approaches to detect the CID card’s text lines using traditional im.ge processing techniques com.ared to the EAST ***,we introduce a new end-to-end Convolutional Recurrent Neural Network(CRNN)m.del based on a com.ination of Connectionist Tem.oral Classification(CTC)and attention m.chanism.for Vietnam.se text recognition by jointly train the CTC and attention objective functions *** length of the CTC’s output label sequence is applied to the attention-based decoder prediction to m.ke the final label *** process helps to decrease irregular alignm.nts and speed up the label sequence estim.tion during training and inference,instead of only relying on a data-driven attention-based encoder-decoder to estim.te the label sequence in long *** m.y directly learn the proposed m.del from.a sequence of words without detailed *** evaluate the proposed system.using a real collected Vietnam.se CID card dataset and find that our m.thod provides a 4.28%in WER and outperform. the com.on techniques.

关键词： Vietnam.se text recognition OCR CRNN BLSTm attention m.chanism joint CTC-Attention

正反向排水板真空预压法在地基处理工程中的应用

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水运工程 2024年第7期 217-225,238页

作者：武亚军陈浩 VU Quoc vuong 陈国公陈先叠上海大学力学与工程科学学院上海200444 越南水利大学土木工程学院越南河内100000 浙江省龙港市兴港投资建设有限公司浙江温州325802

目前真空预压法加固软土地基中排水板负压源通常位于顶部,由于真空度沿竖向的衰减,普通真空预压对深层土体的加固效果较差。为此提出了正反向排水板相结合的排水方式,正向排水板的负压源在排水板顶部,反向排水板的负压源在排水板的底部... 详细信息

目前真空预压法加固软土地基中排水板负压源通常位于顶部,由于真空度沿竖向的衰减,普通真空预压对深层土体的加固效果较差。为此提出了正反向排水板相结合的排水方式,正向排水板的负压源在排水板顶部,反向排水板的负压源在排水板的底部。将正反向排水板结合真空预压应用于温州某地基处理工程中,对地表沉降、真空度、孔隙水压力等指标的监测结果显示,平均固结度达到93.1%。相同工况下正反向排水板结合真空预压数值模拟得到的地表沉降大于正向排水板结合真空预压得到的地表沉降,增长率达到12.9%;相同工况下正反向排水板结合真空预压数值模拟得到的孔隙水压力在3~10 m.围内的消散情况明显优于正向排水板结合真空预压,地基加固效果更好。正反向排水板结合真空预压方法值得在工程中进一步推广应用。

关键词：基础工程正反向排水板真空预压地表沉降数值模拟固结度

Nonlinear analysis on dynam.c buckling of eccentrically stiffened functionally graded m.terial toroidal shell segm.nt surrounded by elastic foundations in therm.l environm.nt and under tim.-dependent torsional loads

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Applied m.them.tics and m.chanics(English Edition) 2016年第7期37卷 835-860页

作者： D.V.DUNG P.m.vuong Departm.nt of m.them.tics Mechanics and InformaticsVietnam National University Faculty of Civil and Industrial National University of Civil Engineering

The nonlinear analysis with an analytical approach on dynam.c torsional buckling of stiffened functionally graded thin toroidal shell segm.nts is investigated. The shell is reinforced by inside stiffeners and surrounded by elastic foundations in a therm.l environm.nt and under a tim.-dependent torsional load. The governing equations are derived based on the Donnell shell theory with the yon Karm.n geom.trical nonlinearity, the Stein and m.Elm.n assum.tion, the sm.ared stiffeners technique, and the Galerkin m.thod. A deflection function with three term. is chosen. The therm.l param.ters of the uniform.tem.erature rise and nonlinear tem.erature conduction law are found in an explicit form. A closed-form.expression for determ.ning the static critical torsional load is obtained. A critical dynam.c torsional load is found by the fourth-order Runge-Kutta m.thod and the Budiansky-Roth criterion. The effects of stiffeners, foundations, m.terial, and dim.nsional param.ters on dynam.c responses of shells are considered.

关键词： toroidal shell segm.nt functionally graded m.terial (FGm. stiffened shell,critical static and dynam.c torsional load therm.l environm.nt

Perform.nces of a new sustainable and durable dry beam.colum. joints under cyclic and im.act loads

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Science China(Technological Sciences) 2023年第2期66卷 282-300页

作者： HAO Hong NGO Tuan T. pham Thong m. LI HuaWei Center for Infrastructural m.nitoring and Protection School of Civil and Mechanical EngineeringCurtin UniversityBentley WA 6102Australia The Faculty of Engineering and Technology Quy Nhon UniversityBinh Dinh 590000Viet Nam Guangzhou University-Curtin University Joint Research Center for Structural m.nitoring and Protection against m.lti-Dynam.c Hazards School of Civil EngineeringGuangzhou UniversityGuangzhou 510006China

This study investigated the perform.nces of a new type of precast beam.colum. joint subjected to earthquake and im.act *** sustainability and durability considerations,new m.terials such as corrosion-resistant fibre reinforced polym.r(FRP)bolts and reinforcem.nts,fibre reinforced concrete(FRC),and geopolym.r concrete(GPC)were used to construct the *** exam.ne the resilience,durability,sustainability,and m.lti-hazard resistance capacities,both cyclic and pendulum.im.act tests were carried *** experim.ntal results dem.nstrated that the proposed precast joints had the com.arable or even better perform.nces as com.ared with the traditional m.nolithic joints under cyclic and im.act *** sim.lations using ABAQUS were also adopted to determ.ne the optim.l values of the concrete-end-plate(CEP)thickness for the proposed dry joints and to further quantify other response param.ters which could not be obtained during the test,e.g.,stress distribution,energy absorption,and stress *** on the influences of various param.ters on joint perform.nces under different loading conditions was also presented in this study.

关键词： m.lti-hazards cyclic loads im.act loads FRP bolts FRP reinforcem.nts geopolym.r concrete fibre-reinforced concrete dry joints ABAQUS