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Shopee越南市场营销策略研究

Shopee越南市场营销策略研究

作者： nguyen ngoc quynh（阮玉琼）贵州大学

学位级别：硕士

随着世界的快速发展和全球经济的现代化,许多新模式问世、改进和替代旧模式。电子商务正在蓬勃发展并逐渐取代传统的购物市场。越南的电子商务市场是一个有发展潜力的市场,同时也面临着来自国内外企业的激烈竞争。其中,Shopee网站和应... 详细信息

随着世界的快速发展和全球经济的现代化,许多新模式问世、改进和替代旧模式。电子商务正在蓬勃发展并逐渐取代传统的购物市场。越南的电子商务市场是一个有发展潜力的市场,同时也面临着来自国内外企业的激烈竞争。其中,Shopee网站和应用程序是最引人注目的。Shopee是越南单日订单量最大的在线电子商务平台之一,虽然比Lazada和Tiki等其他电子商务网站进入越南市场较晚,但它已经在越南制造商、贸易商和分销商中占据了重要地位。鉴于Shopee的现有地位和巨大的市场竞争水平,需要研究Shopee越南市场营销策略中存在的问题并提出更有效和新鲜的营销策略方案,以使商家在瞬息万变的市场中生存。本论文综合运用文献研究法、理论分析法、系统分析法等研究方法。首先对国内外相关理论文献研究现状进行分析和归纳,并概述理论和分析工具。其次,介绍了Shopee在越南市场的宏观环境和行业竞争环境,以及Shopee在越南市场的营销现状和营销策略。然后,运用波特五力模型和SWOT分析法对Shopee在越南市场的营销现状和营销策略中存在的问题进行了剖析,指出了营销策略中存在的主要问题,并总结了 Shopee在越南市场营销中的优势、劣势、机会和威胁。接着,使用STP理论对项目进行了市场细分,锁定了目标市场,并进行了市场定位。然后,评估了Shopee越南市场营销组合策略。最后,再运用7Ps理论对Shopee越南的营销策略进行了细化梳理,并提出了实施保障和改进意见建议。论文研究结果显示,Shopee越南市场营销策略已经相当全面和成功。Shopee拥有强大而富有经验的创始人和领导者。他们拥有各种各样的产品,保护客户和销售商。政策非常灵活和严谨,网页设计非常吸引人和聪明。通过仔细的调查,他们提供了一切方便,能够和很多的交通公司联系,快速,运费便宜,甚至免费。Shopee越南市场营销组合策略也非常成功。到目前为止,Shopee在越南所有著名社交媒体平台上出色地捕捉趋势并应用营销策略。不过,考虑到越南人的心理和消费特点以及激烈的市场竞争,Shopee仍需从定价政策、库存管理、配送政策、尤其是客户关怀政策等方面做出更多的努力,以在在线零售市场中保持领先地位。

关键词： Shopee 越南市场营销策略 STP理论 7Ps理论

Prediction of Shear Bond Strength of Asphalt Concrete Pavement Using Machine Learning Models and Grid Search Optimization Technique

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 691-712页

作者： quynh-Anh Thi Bui Dam Duc nguyen Hiep Van Le Indra Prakash Binh Thai Pham Civil Engineering Department University of Transport Technology54 Trieu KhucThanh XuanHanoi100000Vietnam DDG(R)Geological Survey of India Gandhinagar382010India

Determination of Shear Bond strength(SBS)at interlayer of double-layer asphalt concrete is crucial in flexible pavement *** study used three Machine Learning(ML)models,including K-Nearest Neighbors(KNN),Extra Trees(ET),and Light Gradient Boosting Machine(LGBM),to predict SBS based on easily determinable input ***,the Grid Search technique was employed for hyper-parameter tuning of the ML models,and cross-validation and learning curve analysis were used for training the *** models were built on a database of 240 experimental results and three input variables:temperature,normal pressure,and tack coat *** validation was performed using three statistical criteria:the coefficient of determination(R2),the Root Mean Square Error(RMSE),and the mean absolute error(MAE).Additionally,SHAP analysis was also used to validate the importance of the input variables in the prediction of the *** show that these models accurately predict SBS,with LGBM providing outstanding ***(Shapley Additive explanation)analysis for LGBM indicates that temperature is the most influential factor on ***,the proposed ML models can quickly and accurately predict SBS between two layers of asphalt concrete,serving practical applications in flexible pavement structure design.

关键词： Shear bond asphalt pavement grid search optimization machine learning

Landslide Susceptibility Mapping Using RBFN-Based Ensemble Machine Learning Models

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 467-500页

作者： Landslide Susceptibility Mapping Using RBFN-Based Ensemble Machine Learning Models Duc-Dam nguyen nguyen Viet Tiep quynh-Anh Thi Bui Hiep Van Le Indra Prakash Romulus Costache Manish Pandey Binh Thai Pham Faculty of Civil Engineering University of Transport TechnologyThanh XuanHa Noi100000Vietnam Faculty of Hydraulic Engineering Hanoi University of Civil EngineeringHa Noi100000Vietnam DDG(R)Geological Survey of India Gandhinagar382010India Research Institute of the University of Bucharest Bucharest050663Romania National Institute of Hydrology and Water Management Bucharest013686Romania Department of Civil Engineering Transilvania University of BrasovBrasov500152Romania Danube Delta National Institute for Research and Development Tulcea820112Romania Marwadi University Research Center(MURC) Marwadi UniversityRajkotGujaratBharat360003India Department of Civil Engineering Faculty of Engineering&TechnologyMarwadi UniversityRajkotGujaratBharat360003India

This study was aimed to prepare landslide susceptibility maps for the Pithoragarh district in Uttarakhand,India,using advanced ensemble models that combined Radial Basis Function Networks(RBFN)with three ensemble learning techniques:DAGGING(DG),MULTIBOOST(MB),and ADABOOST(AB).This combination resulted in three distinct ensemble models:DG-RBFN,MB-RBFN,and ***,a traditional weighted method,Information Value(IV),and a benchmark machine learning(ML)model,Multilayer Perceptron Neural Network(MLP),were employed for comparison and *** models were developed using ten landslide conditioning factors,which included slope,aspect,elevation,curvature,land cover,geomorphology,overburden depth,lithology,distance to rivers and distance to *** factors were instrumental in predicting the output variable,which was the probability of landslide *** analysis of the models’performance indicated that the DG-RBFN model,with an Area Under ROC Curve(AUC)of 0.931,outperformed the other *** AB-RBFN model achieved an AUC of 0.929,the MB-RBFN model had an AUC of 0.913,and the MLP model recorded an AUC of *** results suggest that the advanced ensemble ML model DG-RBFN was more accurate than traditional statistical model,single MLP model,and other ensemble models in preparing trustworthy landslide susceptibility maps,thereby enhancing land use planning and decision-making.

关键词： Landslide susceptibility map spatial analysis ensemble modelling information values(IV)

Evaluation of the calibration factors of neutron dose rate meters in a 241Am–Be neutron field

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Nuclear Science and Techniques 2019年第9期30卷 18-23页

作者： Thiem ngoc Le Sy Minh Tuan Hoang quynh ngoc nguyen Hoai-Nam Tran Institute for Nuclear Science and Technology VINATOM 179 Hoang Quoc Viet Hanoi Vietnam Institute of Fundamental and Applied Sciences Duy Tan University Ho Chi Minh City Vietnam

Calibrations were performed for three types of neutron ambient dose equivalent rate meters, i.e., Aloka TPS-451C (Hitachi), KSAR1U.06 (Baltic Scientific Instruments), and Model 12-4 (Ludlum), using a standard field of a 241Am–Be source. The measured total neutron ambient dose equivalent rates, H*(10)' tot, were analyzed to obtain the direct neutron ambient dose equivalent rates, H*(10)' dir, using the ISO 8529-2-recommended generalized- fit method, semiempirical fit method, and reducedfitting method (RFM) fit methods. The calibration factor (CF), defined as the ratio between the conventional true value of the neutron ambient dose equivalent rates in a free field, H*(10)' FF, and H*(10)' dir, was evaluated as one of the important characteristics of the neutron meters in the present work. The fitting results show that the H*(10)' dir values of the meters are in good agreement within the theoretical data within 4%. The averaged CFs of the three neutron meters were evaluated as 0:99 ± 0:01, 1:00 ± 0.03;and 0:99 ± 0:08, respectively. The largest standard uncertainty of these values was determined to be approximately 18.47%(k =1). The standard uncertainty of the CFs obtained using the RFM method was less than 4.23%(k=1), which is the smallest uncertainty among the three methods.

关键词： Neutron meter Calibration factor ^241 Am–Be source

Association between measles antibodies in vaccinated and naturally infected mothers with protective antibodies and the occurrence of measles in their children:A cross-sectional study in the Bavi district of Hanoi

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Asian Pacific Journal of Tropical Medicine 2019年第9期12卷 404-408页

作者： Cam Nhat nguyen quynh ngoc nguyen Than Huu Dao Le Thi quynh Mai Infectious Disease Prevention und Control Department Center for Disease ControlHonoiVietnom Virology Department National Institute of Hygiene and EpidemiologyHanoiVietnam

Objective:To determine the concentration and rate of decay of maternal IgG antibodies against measles prevalence in infants of vaccinated or naturally infected mothers and study initial measles immunization occurs in nine-month-old ***:In total,401 pregnant women and the same number of their subsequent newborns were recruited in the Bavi district of Hanoi in 2016-2017;they were divided into two groups:Older women(born before 1985,n=201)and younger women(born after 1990,n=200).Samples were collected at five time-points;week 36 of pregnancy,birth(cord),and 3,6,and 9 months after ***-specific IgG antibody levels were ***:In total,77.06% of the 401 pregnant women were seropositive for measles-specific IgG antibodies.A significantly greater proportion of mothers aged 30 and older(88.06%)and their newborn(93.53%)were seropositive compared to the mothers aged 25 and younger(66.00%),and their newborn(72.00%)(P<0.001).The infants of older mothers had significantly higher geometric mean titres(GMT)of measles IgG antibodies than the infants of younger mothers(P<0.001)at all time-points of the study *** proportion of measles IgG antibodies together with GMT decreased from 82.97%(506.96)at the age of three months to 23.19%(45.22)at the age of nine ***:This study provides a profile of maternal antibodies against measles in Vietnamese infants and investigates the early susceptibility to measles in both the infants of vaccinated mothers and mothers with naturally acquired *** data suggest that determining the appropriate age for measles vaccination is paramount for the elimination of measles in Vietnam.

关键词： Infant Measles Seropositive National Expanded Program of Immunization Vietnam

Calibration of a neutron dose rate meter in various neutron standard fields

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Nuclear Science and Techniques 2020年第6期31卷 75-82页

作者： Tuan Khai nguyen Hoai-Nam Tran quynh ngoc nguyen Thi My Linh Dang Van Loat Bui Thiansin Liamsuwan ngoc-Thiem Le Vietnam Agency for Radiation and Nuclear Safety 113 Tran Duy HungHanoi 100000Vietnam Institute of Fundamental and Applied Sciences Duy Tan UniversityHo Chi Minh 700000Vietnam Faculty of Natural Sciences Duy Tan University3 Quang TrungDa Nang 550000Vietnam Institute for Nuclear Science and Technology VINATOM179 Hoang Quoc VietHanoi 100000Vietnam Faculty of Physics VNU University of Science334 Nguyen TraiHanoi 100000Vietnam Nuclear Research and Development Division Thailand Institute of Nuclear TechnologyOngkharakNakorn NayokThailand 7 Faculty of Medicine and Public HealthHRH Princess Chulabhorn College of Medical ScienceChulabhorn Royal AcademyBangkokThailand

This paper presents the calibration of a neutron dose rate meter and the evaluation of its calibration factors(CFs)in several neutron standard fields(i.e.,two standard fields with bare sources of252Cf and241Am-Be,and five simulated workplace fields with241Am-Be moderated sources).The calibration in standard fields with bare sources was conducted by following the recommendations of the ISO 8529 *** measured total neutron ambient dose equivalent rates,denoted as H*(10)tot,were analyzed to obtain direct components,denoted as H*(10)dir,using a reduced fitting *** CF was then calculated as the ratio between the conventional true value of the neutron ambient dose equivalent rate in a free field,denoted as H*(10)FF,and the value of H*(10)*** contrast,in the simulated workplace neutron fields,the calibration of the neutron dose rate meter was conducted by following the ISO 12789 *** CF was calculated as the ratio between the values of H*(10)totmeasured by a standard instrument(i.e.,Bonner sphere spectrometer)and the neutron dose rate *** CF values were obtained in the range of 0.88–*** standard uncertainties(k=1)of the CFs were determined to be in the range of approximately 6.6–13.1%.

关键词： Neutron standard fields Neutron dose rate meter Calibration factor 252Cf source 241AmBe source

Spectral properties of the surface reflectance of the northern polar region of Mercury

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Research in Astronomy and Astrophysics 2020年第3期20卷 92-107页

作者： nguyen Bich ngoc Nicolas Bott Pham ngoc Diep Department of Astrophysics Vietnam National Space CenterVietnam Academy of Science and Technology18 Hoang Quoc VietCau GiayHanoiVietnam Laboratoire d'Etudes Spatiales et d' Instrumentation en Astrophysique l'Observatoire de Paris5 place Jules Janssen 92195 MeudonFrance

We analyze MESSENGER reflectance measurements covering the northern polar region of Mercury,the least studied region of the northern mercurian *** use observations from the Mercury Dual Imaging System Wide-Angle Camera(MDIS/WAC)and the Mercury Atmospheric and Surface Composition Spectrometer(MASCS/VIRS)to study the spectral dependence of the surface *** results obtained from the observations made by both instruments are remarkably *** find that a second degree polynomial description of the measured reflectance spectra gives very good fits to the data and that the information that they carry can best be characterized by two parameters,the mean reflectance and the mean relative spectral slope,averaged over the explored range of *** properties of the four main types of terrains known to form Mercury’s regolith in the northern region,smooth plains(SPs),heavily cratered terrain(HCT),fresh ejecta/materials and red pitted ground(RPG),are examined in terms of these two *** results are compared,and found consistent with those obtained by earlier studies in spite of difficulties met in obtaining accurate reflectance measurements under the large incidence angle condition characteristic of polar *** results will help with the preparation of the BepiColombo mission and with supporting its observational strategy.

关键词： planets and satellites terrestrial planets-planets and satellites surfaces-techniques spectroscopic

The effectiveness of light emitting diode(LED)lamps in the offshore purse seine fishery in Vietnam

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Aquaculture and Fisheries 2023年第5期8卷 551-557页

作者： nguyen Dang Nhat Do Thanh Tien Truong Van Dan nguyen Duy quynh Tram nguyen Quang Lich Ho Dang Phuc nguyen ngoc Phuoc School of Engineering and Technology Hue University01 Dien Bien PhuHue City52000Viet Nam Faculty of Engineering and Food Technology University of Agriculture and ForestryHue University102 Phung HungHue City52000Viet Nam Faculty of Fisheries University of Agriculture and ForestryHue University102 Phung HungHue City52000Viet Nam Institute of Mathematics Vietnam Academy of Science and Technology18 Hoang Quoc VietCau Giay DistrictHanoi11300Viet Nam

Fishing with artificial light has become one of the most advanced,efficient,and common methods for the night-time purse seining in *** study evaluated the radiation spectrum,CIE chromaticity coordinates,correlated color temperature(CCT),catch rate,fuel consumption,and CO_(2)emissions when using Light emitting diode(LED)lamps(0.196 kW)in comparison with the use of metal halide(MH)lights(1 kW)in the offshore purse seine fishery in Quang Tri province,*** fishing efficiency of the purse seine fishing boats using LED lamps has increased 1.58 times in catch rate than MH lights,although the energy consumption of LED lamp is 4 times *** consumption of boats per trip using LED lamps was one third of that using MH *** use of LED reduced the radiation spectrum,especially the intense UV radiation which negatively affects the health of *** study also showed the potential of CO_(2)emission reduction up to 1.09 tons of CO_(2)per trip per boat from the use of LED lamps in the offshore purse seine fishing boats.

关键词： Light emitting diode(LED)lamp Metal halide(MH)light Offshore purse seine fishery Quang tri province Vietnam

Electronic Band Structure of Carbon Nanotubes with Kekule Structure

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Chinese Physics Letters 2013年第9期30卷 97-100页

作者： nguyen ngoc Hieu Le Cong Nhan Center of Research and Development Duy Tan UniversityK7/25 Quang TrungDa NangViet Nam Department of Environmental Science Saigon University273 An Duong VuongHo Chi Minh cityViet Nam

Electronic band structure of carbon nanotubes with the Kekule structure is studied by the tight-binding *** give a complete geometrical approach to structural properties of carbon nanotubes with bond alternation,including chiral and achiral *** the Kekule is introduced,all carbon nanotubes become semiconducting with a small band gap at the Fermi *** band gap of the carbon nanotubes depends only on the difference between C–C bond lengths or the resonance integrals.

关键词： carbon structure Fermi