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A Multiplicative Seasonal ARIMA/GARCH Model in EVN Traffic Prediction

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International Journal of Communications, Network and System Sciences 2015年第4期8卷 43-49页

作者： Quang thanh tran Zhihua Ma Hengchao Li Li Hao Quang Khai Trinh Sichuan Provincial Key Laboratory of Information Coding and transmission Southwest Jiaotong University Chengdu China Beijing Branch of China United Network Communications Co. Ltd. Beijing China Telecommunication Department University of Transport and Communications Hanoi Vietnam

this paper highlights the statistical procedure used in developing models that have the ability of capturing and forecasting the traffic of mobile communication network operating in Vietnam. To build such models, we follow Box-Jenkins method to construct a multiplicative seasonal ARIMA model to represent the mean component using the past values of traffic, then incorporate a GARCH model to represent its volatility. The traffic is collected from EVN Telecom mobile communication network. Diagnostic tests and examination of forecast accuracy measures indicate that the multiplicative seasonal ARIMA/GARCH model, i.e. ARIMA (1, 0, 1) × (0, 1, 1)24/GARCH (1, 1) shows a good estimation when dealing with volatility clustering in the data series. this model can be considered to be a flexible model to capture well the characteristics of EVN traffic series and give reasonable forecasting results. Moreover, in such situations that the volatility is not necessary to be taken into account, i.e. short-term prediction, the multiplicative seasonal ARIMA/GARCH model still acts well with the GARCH parameters adjusted to GARCH (0, 0).

关键词： Traffic Prediction ARIMA GARCH Multiplicative Seasonal ARIMA/GARCH EViews

Controllers Design for the Multi-Shuttle and Multi-Station transportation System

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Open Journal of Applied Sciences 2021年第8期11卷 946-965页

作者： Tien Dong Ha Minh Tien Trinh tran thanh Cong Vu Tuong Quan Vo Faculty of Mechanical Engineering Ho Chi Minh City University of Technology VNU-HCM Viet Nam

Nowadays, the Multi-Shuttle and Multi-Station transportation System (MMTS) is one of the most interesting research topics in many fields of industries. It is an effective solution to reduce unexpected accidents that occur during transportation as well as increase productivity in manufacturing. The aim of this paper is to introduce the controller design for the MMTS which is built in our BK-Recme BioMech Lab at Ho Chi Minh City University of Technology (VNU-HCM), Viet Nam. Based on the design of this system, the control algorithms will be conducted to check the operation of the whole system. To evaluate the feasibility and effectiveness of this model, we design a series of random instances for different quantities of nodes as well as the different quantities of shuttles. Our system includes 4 stations and 6 shuttles which are assembled in the serial chain system. However, the number of stations and number of shuttles can be expanded to any desired ones which are based on the requirement of the industries. In this paper, we mainly focus on the controller design of this system to make it operate in an effective way that the goods will be transported and delivered to the target station as fast as possible. In order to solve the large-scale instances and realistic transport problems, we propose three algorithms for three progresses as shuttles calling, path reading and shuttles communicating. The shuttles calling is to decide which shuttle should be called to the start-node. Path reading to determine the shortest way to go from start-node to end-node. Finally, shuttles co

关键词： Multi-Station Multi-Shuttle transportation Shuttle Calling RFID Communicating Start-Node End-Node

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太滆运河污染源调查与分析

安徽农学通报 2017年第20期23卷 66-68页

作者： tran Ngoc Binh Tang Van Tai Tang thi thanh Sang 华中科技大学同济医学院湖北武汉430074 越南荣市医学大学公共卫生学院东南大学土木工程学院江苏南京211189 越南荣市大学

太滆运河是主要入太湖河流之一,在沟通太湖和滆湖方面起到了极为重要的作用。要治理太滆运河,就必须摸清运河周边污染源的存在情况,搞清楚一些主要点源污染的位置及具体污染情况,因此对太滆运河沿岸污染源进行彻底的调查就十分有必要。... 详细信息

太滆运河是主要入太湖河流之一,在沟通太湖和滆湖方面起到了极为重要的作用。要治理太滆运河,就必须摸清运河周边污染源的存在情况,搞清楚一些主要点源污染的位置及具体污染情况,因此对太滆运河沿岸污染源进行彻底的调查就十分有必要。通过调研与观察,该研究总结了太滆运河主要污染来源,包括:工业点源污染,农业源污染及其他污染源,同时分析了污染对坏境生态的潜隐危害。

关键词：太湖流域太滆运河污染源河道水体污染

Complex Network Analysis of the Robustness of the Hanoi, Vietnam Bus Network

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Journal of Systems Science & Complexity 2019年第5期32卷 1251-1263页

作者： tran Vu Hieu CHEONG Siew Ann BUI Ngoc Dung Faculty of Information Technology University of Transport and CommunicationsHanoiVietnam Division of Physics and Applied Physics School of Physical and Mathematical SciencesNanyang Technological University21 Nanyang Link637371Singapore Faculty of Information Technology University of Transport and CommunicationsHanoiVietnam.

Many complex networks exist to facilitate the transport of material or information. In this capacity, the authors are often concerned with the continued flow of material or information when a fraction of the links in the complex network is disrupted. In other words, the authors are interested in the robustness of the complex network. In this paper, the authors survey measures of robustness like the average path length, the average clustering coefficient, the global efficiency, the size of largest cluster and use these to analyze the robustness of the bus network in Hanoi, Vietnam. The authors find that the bus network is robust against random failure but sensitive to targeted attack, in agreement with its scale-free character. By examining sharp drops in the average path length within the largest cluster of the Hanoi bus network under successive targeted attack, the authors identify five nodes whose loss lead to the fragmentation of the network into five or six disconnected clusters. These isolated clusters represent geographically the Central, Western, Southern, and Northwestern districts of Hanoi. Special considerations must therefore be given to these five nodes when planners wish to expand the bus network, or make it more robust.

关键词： Complex network hanoi bus network random failure robustness targeted attack

The Reform Process of Higher Education in Vietnam: Performance Efficiency and transparent Accountability

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Review of Educational Theory 2018年第4期1卷 121-133页

作者： Carolyn-Dung thi thanh tran International College of Management Manly NSW 2095 University of New England Armidale NSW 2350

After more than three decades of implementing the Doi Moi policy, Vietnam's higher education has achieved significant progress, in terms of policies of national reform and strategies of international cooperation. However, the role and place of tertiary education institutions in the world's education market are still unclear. Although a number of researchers have highlighted a range of impediments to its development, realistic solutions have not been devised to help Vietnam accelerate its progress in education. The main objectives of this paper are to review reform in government policies pertaining to renovation of the tertiary education sector, discuss the performance efficiency of higher education institutions using statistical analyses based on the findings from recent studies, and propose possible solutions for enhancing performance efficiency and transparent accountability of institutions in the process of the renovation of the sector.

关键词： Challenges the Doi Moi policy University Efficiency Renovation

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农田生态沟渠效能研究

黑龙江生态工程职业学院学报 2017年第5期30卷 5-7,68页

作者： Tang Van Tai tran Ngoc Binh Tang thi thanh Sang Le Hong Hanh 东南大学土木工程学院江苏南京210096 Vinh Medical University Vinh University

传统混凝土沟渠主要使用浆砌石、钢筋混凝土等材料建造成排水沟渠,难以有效去除农田污水中的富营养化,引起河道污染~[1]。本实验在调查太湖运河沿岸农田的污染情况的基础上,设计并建造复合生态沟渠示范工程,然后根据季节差异种植复合的... 详细信息

传统混凝土沟渠主要使用浆砌石、钢筋混凝土等材料建造成排水沟渠,难以有效去除农田污水中的富营养化,引起河道污染~[1]。本实验在调查太湖运河沿岸农田的污染情况的基础上,设计并建造复合生态沟渠示范工程,然后根据季节差异种植复合的植物。通过观察植物生长情况研究生态沟渠的植生价值,检测生态沟渠的水质变化情况以检验农田污水富营养化的去除效能。

关键词：生态沟渠农田污水太滆运河

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越南义安省沿海红树林保护与修复方法探析

法制与经济 2016年第12期25卷 154-156页

作者： Tang thi thanh sang tran Ngoc Binh Nguyen Nhu Anh Tang Vm Tai 越南荣市大学越南荣市东南大学土木工程学院江苏南京210096

红树林是热带气候地区特有的景观,也是国家珍贵的自然资源。红树林在修复生态多样性、防治自然灾害、保护生态环境、促进经济发展等方面发挥着重要作用。受自然和人为因素的影响,红树林的面积正快速减少,探寻保护和修复红树林的方法已... 详细信息

红树林是热带气候地区特有的景观,也是国家珍贵的自然资源。红树林在修复生态多样性、防治自然灾害、保护生态环境、促进经济发展等方面发挥着重要作用。受自然和人为因素的影响,红树林的面积正快速减少,探寻保护和修复红树林的方法已迫在眉睫。文章以越南义安省沿海红树林为例,对红树林遭受破坏的原因、红树林保护现状、修复及保护工作难点等方面进行研究,从而提出有效可行的保护与修护方法。

关键词：红树林资源保护生态修复

越南阮朝帝王服饰及其在现代越南服饰中的应用研究

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越南阮朝帝王服饰及其在现代越南服饰中的应用研究

作者：陈青玄（tran thanh HUYEN）西南大学

学位级别：硕士

19世纪是阮朝的顶峰时期,以儒家思想为核心的统治思想在服装上具有一定的影响。阮朝（1802至1945年）存在了143年,期间发生的一些事件使得文化和服饰发生了转变,尤其是宫廷服饰发生了更多的变化。本文以阮朝皇帝服饰作为研究对象,重点对... 详细信息

19世纪是阮朝的顶峰时期,以儒家思想为核心的统治思想在服装上具有一定的影响。阮朝（1802至1945年）存在了143年,期间发生的一些事件使得文化和服饰发生了转变,尤其是宫廷服饰发生了更多的变化。本文以阮朝皇帝服饰作为研究对象,重点对1802年至1847年期间三位皇帝的主要服饰形制进行了研究。越南阮朝皇帝服饰上的特色性比如颜色,图案,装饰与形式可以成为越南的传统元素代表。希望该研究结果能够让更多的人了解阮朝服饰文化,对阮朝的服饰文化起到保护和传承;为有关阮朝的影视作品中服饰的设计有所帮助;为阮朝元素在现代服装中的设计运用提供思路。笔者通过在越南的实践考察——越南阮朝帝王服饰及其在现代越南服饰中的应用研究。因此本文主要提出三个目的:第一:保护和弘扬越南传统文化,使其得以传承。每一个国家和民族都拥有自己的历史,在这个历史发展过程中沉淀出的文化,是这个国家的岁月韵味和精神遗产。保存传统的文化,首先应该是本国人民对自己传统文化的认可,在这个基础上得以传承和发扬,让外界了解这个国家和民族,才能客观上形成一种对外的影响能力,同时也为人类文明的发展史进行了填充。在社会改革和商品经济的影响下,越南的文化发生了很大的转变,人们对传统文化的认知随着科技的发展逐渐被遗落、淡忘。第二:通过对越南阮朝服饰资料的收集整理,为有关历史影视的服饰造型和书籍服饰的描述提供参考。越南电影集团想通过电影再现历史或者拍一个有古代风味的电视剧,但是由于没有具体的资料或则所得资料的来源不一,且资料内容大多受中国古代服装的影响,使其结果出现意见不统一或与中国古装电视剧服饰相同的现象。由于大部分关于越南宫廷服装的资料的遗失或流落在民间,因此本文拟通过准确地收集阮朝皇帝服装的样式、结构、颜色等,以此弥补相关研究的不足,并希望能为今后越南影视或话剧等服饰的设计提供一定的参考价值。第三,为越南阮朝传统服饰特征运用到现代越南服装设计中提供设计思路和方法。由于阮朝传统服饰同现代服饰在造型、风格、气质、工艺效果方面存在极大的差异,因此在现在服装中我们应该研究的问题是以怎样的形式作为媒介将传统体现于现代服装而又不失时尚。因此本文通过材质、用色、图案的改良的设计思路,将阮朝传统元素与现代气息融合,使设计作品在款式和风格气质上达到了完美的和谐统一、丝毫不让人感觉突兀,甚至它还充当着该设计中画龙点睛的角色。通过对收集到的资料进行归纳和整理,从服装的三要素（款式、色彩、面料）对传统服装特征在当代越南服饰上的再现形式进行了较为全面的分析、归纳和总结,最后根据研究结果,将其主要特征应用于现代服装,进行了系列设计。笔者对越南北方到越南的中部的文献资料进行收集整理,主要通过三种研究方法（文献阅读、访谈法、观察法）对阮朝帝王服饰进行资料的收集分析,并通过与同时间段、同思想下的中国朝代帝王服饰进行参照对比,便与读者了解。本论文不仅集中研究阮朝皇帝服装以应用到现代服装设计,而且还具体地反映了越南古代服装系统里阮朝服装的内容。研究不能停止在这里,因为越南古装服装系统还需要补充,专业资料方面的空缺仍需填补。本人希望本研究会对此有所帮助。即使将来会有新意见,新发现巩固或者反驳文章里面的某个结论,不管随着哪个方向,本人也认为那是给越南服饰文化研究的积极帮助。希望该研究结果能为传统越南服饰在现代服饰中的传承提供可以参考的设计思路。

关键词：越南阮朝阮朝服装越南现代服装

Factors Affecting the Profitability of Cement ManufacturingEnterprises in Tuyen Quang Province

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Macro Management & Public Policies 2022年第2期4卷 20-28页

作者： Hoang Anh Dao Pham thanh Tra tran Thao Nguyen Tantrao University Yenson DistrictTuyenquang ProvinceVietnam

this study focuses on analyzing the factors affecting the production and business efficiency of cement manufacturing enterprises in Tuyen Quang province. Production and business efficiency is measured by profitability ratios including return on assets (ROA), return on equity (ROE) and return on sales (ROS). Using a quantitative research method through estimating a linear regression model based on data of two cement manufacturing companies in the period 2019-2021, the research results show that the factors affecting business efficiency of cement manufacturing enterprises in Tuyen Quang province include size of enterprise, cost ratio, average collection period, inventory turnover, fixed assets turnover and debt ratio.

关键词： Business efficiency Profitability Cement manufacturing enterprises Tuyen Quang