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A TCP Performance Enhancement Scheme in Infrastructure based Vehicular Networks

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China Communications 2015年第6期12卷 73-84页

作者： ha le FANG Lijin BI Yuanguo LIU Wei Northeastern University Shenyang Ligong University

Transmission Control Protocol （TCP） in infrastructure based vehicular net- works is dedicated to support reliable Intemet services for mobile users. However, an end-to- end TCP flow not only experiences some com- mon challenges in wireless mobile networks, such as high packet loss rate, medium access competition, unstable wireless bandwidth, and dynamic topology, etc., but also suffers from performance degradation due to traffic congestion at the Road-Side Units （RSUs） that connect the wireline and wireless networks. In order to address the challenging issues related to reliable TCP transmissions in infrastruc- ture based vehicular networks, we propose an RSU based TCP （R-TCP） scheme. For wireline source nodes, R-TCP adopts a novel flow control mechanism to adjust transmission rates according to the status of bottleneck link. Specifically, during the short wireless connec- tion time in Infrastructure based vehicular net- works, R-TCP quickly chooses an ideal trans- mission rate for data transmissions instead of activating the slow start algorithm after the connection is established, and successfully avoids the oscillation of the transmission rate. Simulation results show that R-TCP achieves great advantages than some relate proposals in terms of throughput, end-to-end delay, and packet loss rate.

关键词： rate control bottleneck node packet loss infrastructure based vehicular net-works

Suzuki Reaction of Aryl Bromides Using a Phosphine-Free Magnetic Nanoparticle-Supported Palladium Catalyst

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催化学报 2011年第11期32卷 1667-1676页

作者： Nghia T. BUI Trung B. DANG ha V. le Nam T. S. PhaN Department of Chemical Engineering HCMC University of Technology VNU-HCM 268 Ly Thuong Kiet Distriet 10 Ho Chi Minh City Viet Nam

A palladium catalyst immobilized on superparaganetic nanoparticles was prepared with a palladium loading of 0.30 mmol/g. The catalyst was characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometry, thermogravimetric analysis, Fourier transform infrared, atomic absorption spectrophotometry, and nitrogen adsorption. The immobilized palladium catalyst was an efficient catalyst without added phosphine ligands for the Suzuki cross-coupling reaction of several aryl bromides with phenylboronic acid. The recovery of catalyst was simply by magnetic decantation in the presence of a magnet. The immobilized palladium catalyst can be reused many times without significant degradation in catalytic activity. No leaching of active palladium species into the reaction solution was detected.

关键词： superparamagnetic nanoparticle Suzuki reaction palladium aryl bromide

Dry eye rate and its relationship with disease stage in patients with primary hypertension:a cross-sectional study in Vietnam

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 653-658页

作者： Tran Tat Thang Pham Hong Phuong Nguyen Sa Huynh Nguyen Trung Kien NguyenDuy Toan Nguyen Thi Thu ha le ha Khoa Nguyen Huu Dung Thai Doan Thang le Viet Thang Nghe An Eye Hospital Nghe An 43000Vietnam Nghe An Friendship General Hospital Nghe An 43000Vietnam Military Hospital 103 Ha Noi 100000Vietnam Vietnam Military Medical University Ha Noi 100000Vietnam hanoi Medical University Ha Noi 100000Vietnam Bạch Mai Hospital Ha Noi 100000Vietnam TTH Vinh General Hospital Nghe An 100000Vietnam

AIM:To determine the dry eye(DE)rate and its relationship with disease stage in patients with primary ***:A cross-sectional study included 432 patients with primary hypertension(with an equal number of patients in each group:144 in stage Ⅰ,Ⅱ,and Ⅲ hypertension)and 144 healthy subjects as a control *** Ocular Surface Disease Index(OSDI)and Schirmer Ⅰ test without anesthetics were conducted on all 576 *** with OSDI scoreshan in the control group(41.7%versus 18.8%;Plevels in hypertension patients with DE were higher than those without DE,Plevated plasma creatinine,and CRP-hs levels were independent factors associated with DE in primary hypertension patients,Plevated plasma CRP-hs,and creatinine levels in patients with primary hypertension.

关键词： primary hypertension dry eye stage of hypertension plasma creatinine

Polygonatum kingianum rhizome extract alleviates collagen antibody-induced arthritis by modulating proinflammatory cytokine production in mice

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Asian Pacific Journal of Tropical Biomedicine 2020年第11期10卷 490-495页

作者： Huyen Do Thi Thanh Phuong Ngo Thi Hien Nguyen Thi Thu Nga Nguyen Thi Hung le Ngoc Thao DoThi ha le Minh Graduate University of Science and Technology Vietnam Academy of Science and Technology18 Hoang Quoc VietNghia DoCau GiayHanoiVietnam Institute of Natural Products Chemistry Vietnam Academy of Science and Technology18 Hoang Quoc VietNghia DoCau GiayHanoiVietnam hanoi Open University101 Nguyen Hien str Hai Ba Trung Dist.HanoiVietnam Laboratory of Bioassay Institute of BiotechnologyVietnam Academy of Science and Technology18 Hoang Quoc VietNghia DoCau GiayHanoiVietnam Chemistry Lab Project Center for Research and Technology transferVietnam Academy of Science and Technology18 Hoang Quoc VietNghia DoCau GiayHanoiVietnam

Objective: To evaluate the anti-arthritic effects of Polygonatum kingianum rhizome extract using both in vitro and in vivo ***: Lipopolysaccharide-induced RAW 264.7 macrophages were treated with an ethanol extract of Polygonatum kingianum rhizomes at different concentrations to determine nitric oxide and prostaglandin E2(PGE2) production. For in vivo study, Polygonatum kingianum ethanol extract was further investigated for its antiinflammatory effect in a mouse model with collagen antibodyinduced arthritis. Phytochemical study of Polygonatum kingianum ethanol extract was also ***: Saponins(142 mg/g total yield) was the main component in the Polygonatum kingianum ethanol extract. 5α,8α-ergosterol peroxide,(E,E)-9-oxooctadeca-10,12-dienoic acid and 3-(2?-hydroxy-4?-methoxy-benzyl)-5,7-dihydroxy-8-methyl-chroman-4-one were isolated from the extract. Polygonatum kingianum ethanol extract exhibited potential anti-inflammatory effects by inhibiting nitric oxide and PGE2 production in RAW 264.7 cells in a dosedependent manner. The level of arthritis in mice with collagen antibody-induced arthritis was significantly reduced(Phanol extract, particularly at a dose of 1 000 mg/kg body weight. Besides, the extract demonstrated the regulatory effects on serum tumor necrosis factoralpha, interleukin-6, and interleukin-10 in treated ***: Polygonatum kingianum ethanol extract has beneficial effects on inflammatory cytokine regulation and PGE2 inhibition in an experimental mouse model with collagen antibody-induced arthritis. The phytochemical screening reveals that the saponin, as the main component, and sterols(daucosterol and 5α,8α-ergosterol peroxide) from Polygonatum kingianum ethanol extract may contribute to its promising in vitro and in vivo anti-inflammatory activities.

关键词： inflammatory cytokine PGE2

A comparative analysis of weight-based machine learning methods for landslide susceptibility mapping in ha Giang area

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Big Earth Data 2023年第4期7卷 1005-1034页

作者： Thanh Trinh Binh Thanh Luu Trang ha Thi le Duong Huy Nguyen Trong Van Tran Thi hai Van Nguyen Khanh Quoc Nguyen Lien Thi Nguyen Faculty of Computer Science Phenikaa UniversityYen NghiaHa DongHanoi 12116Vietnam Phenikaa Research and Technology Institute(PRATI) A&A Green Phoenix Group JSCNo.167 Hoang NganTrung HoaCau GiayHanoi 11313Vietnam Northwestern Geological Division General Department of Geology and Minerals of VietnamHanoiVietnam Youth union office Thuyloi University175 Tay SonDong DaHanoiVietnam Center of Remote Sensing and Geohazards Vietnam Institute of Geosciences and Mineral ResourcesHanoiVietnam

Landslide susceptibility maps (LSMs) are very crucial for planningpolicies in hazardous areas. However, the accuracy and reliability ofLSMs depend on available data and the selection of suitable *** study is conducted to produce LSMs by combinations of machinelearning methods and weighting techniques for ha Giang province,Vietnam, where has limited data. In study area, we gather 11 landslideconditioning factors and establish a landslide inventory *** the weights of classes (or factors) is very important toprepare data for machine learning methods to generate LSMs. Wefrst use frequency ratio (FR) and analytic hierarchy process (AHP)techniques to generate the weights. Then, random forest (RF), supportvector machine (SVM), logistic regression (LR), and AHP methods arecombined with FR and AHP weights to yield accurate and reliableLSMs. Finally, the performance of these methods is evaluated by fivestatistical metrics, ROC and R-index. The empirical results have shownthat RF is the best method in terms of R-index and the five metrics, *** rate (0.9661), FP rate (0.0), ACC (0.9835), MAE (0.0046), and RMSE(0.0350) for this study area. This study opens the perspective of weightbasedmachine learning methods for landslide susceptibility mapping.

关键词： Landslide logistic regression random forest SvM Vietnam

考虑生态环境因素的农业生产效率——来自我国各省、区、市2003～2011年的实证分析

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系统工程 2016年第5期34卷 102-111页

作者：哈乐群陕西理工学院管理学院陕西汉中723001

农业生产对环境的污染日益严重。将生态环境因素纳入农业生产效率的考察是研究的新方向。本文采用DEA的方法,将化肥和农药的流失作为非期望产出,构建线性规划模型,对我国31个省、区、市2003-2011年的数据进行实证分析,结果表明：北京、... 详细信息

农业生产对环境的污染日益严重。将生态环境因素纳入农业生产效率的考察是研究的新方向。本文采用DEA的方法,将化肥和农药的流失作为非期望产出,构建线性规划模型,对我国31个省、区、市2003-2011年的数据进行实证分析,结果表明：北京、天津、上海等11个省份的农业生产效率达到了DEA有效;有些省份未达到DEA有效的原因是自然条件的束缚,如陕西、宁夏等;有些省份是由于农业支持力度不够,如内蒙古和辽宁;环境因素是造成其非DEA有效的普遍原因,针对这些情况,本文给出了具体的改进目标。

关键词：生态环境因素农业生产效率非期望产出

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越南学生汉语动物成语习得偏误分析

越南学生汉语动物成语习得偏误分析

作者： TRUONG le ha NHU 重庆交通大学

学位级别：硕士

汉语成语一直被认为是中华文化的精华,是汉语学习过程中不可忽视的一部分。现在学习汉语的越南人越来越多。对越南学生来说,仅会简单说一点汉语是不够的,他们希望了解更多成语,更深层次地了解汉语成语背后的文化,提高汉语运用能力。但... 详细信息

汉语成语一直被认为是中华文化的精华,是汉语学习过程中不可忽视的一部分。现在学习汉语的越南人越来越多。对越南学生来说,仅会简单说一点汉语是不够的,他们希望了解更多成语,更深层次地了解汉语成语背后的文化,提高汉语运用能力。但由于动物成语的丰富性、结构的稳定性、意义的整体性和语法功能的多样性以及汉语文化背景、风俗习惯的多元性,再加上两国的地理环境及国家的民族思维方式存在差异,两国人民对同一种动物的联想在认知和理解上也存在很多差异。这导致越南学生很难掌握动物成语知识,在应用成语中常常出现偏误。因此,笔者作为越南学生,为了帮助越南学生更深入地学习和理解汉语动物成语,拟研究越南学生在汉语动物成语习得过程中遇到的偏误,归纳偏误类型,分析偏误原因并提出针对性的学习策略。本研究通过深入分析汉语与越南语动物成语的构词特点和文化内涵差异,揭示了语言结构和文化背景理解不足是导致越南学生在学习汉语动物成语时产生偏误的主要原因。通过设计并实施调查问卷,详细分析了越南学生在汉语动物成语学习中的具体偏误类型,包括语义偏误、语法偏误和语用偏误。调查结果显示,这些偏误不仅影响了学生运用语言的准确性,也限制了他们对汉语文化深层次的理解。针对发现的问题,本文提出了相应的对策,旨在帮助越南学生克服学习障碍,深化对汉语动物成语及其背后文化的理解。这些对策包括加强文化背景知识学习、采用成语分类和归纳法,以及通过多样化的学习活动和资源创造丰富的学习环境。研究强调通过多媒体资源、实践互动和中越文化交流活动等手段,激发学生的学习兴趣,提高其汉语成语的实际应用能力。本研究对于汉语作为第二语言的教学实践具有重要意义。通过实施本研究提出的学习对策,不仅可以有效减少越南学生在汉语成语学习中的偏误,还可以促进中越文化的交流与理解,为越南学生提供一条深入学习汉语、提升跨文化交际能力的有效途径。

关键词：越南学生动物成语偏误分析学习策略

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汉越度量形容词特定句法框架之比较

汉越度量形容词特定句法框架之比较

作者：何励（ha le）华中师范大学

学位级别：硕士

本论文主要内容,共有六章和二十小节,从表和里两个方面,讨论汉语和越南语度量形容词特定的六个句法框架。第一章分成四节,说明了汉语度量形容词的概念与划分、度量形容词的特殊性、句法框架结构及汉语和越南语结构句法功能的比较。第二... 详细信息

本论文主要内容,共有六章和二十小节,从表和里两个方面,讨论汉语和越南语度量形容词特定的六个句法框架。第一章分成四节,说明了汉语度量形容词的概念与划分、度量形容词的特殊性、句法框架结构及汉语和越南语结构句法功能的比较。第二章共有三节,讨论和比较“有+数词+度量衡单位+A”结构的组合顺序、组合成分、语义表达。第三章分成三节,首先讨论“多/余”进入“数量形结构”受数词约束,然后分析和比较“数词+度量衡单位+多/余+A”结构的组合成分和语义表达。第四和第五章分别讨论和比较两个句法框架“数词+度量衡单位+来+A”、“数词+度量衡单位+半+A”的组合顺序、组合成分及语义表达。第六章共有四节,讨论和比较“有+数词+个体量词+名词+A”结构的组合顺序、组合成分、句法功能及语义表达。另外,论文还有前言和结语。前言部分阐述研究目的、研究现状、研究范围、研究方法及语料来源。结语部分总结本论文内容,提出汉语和越南语在度量形容词方面的共同点与特点。

关键词：度量形容词句法框架比较数量结构

Detecting Anomalies in Irregular Data Using K-means Clustered Signal Dictionary

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Computer Technology and Application 2016年第5期7卷 244-252页

作者： G. Talavera Reyes Rajan M. Chandra ha Thu le Zekeriya Aliyazicioglu Electrical and Computer Engineering Department California State Polytechnic University Pomona CA 91768 United States

The critical nature of satellite network traffic provides a challenging environment to detect intrusions. The intrusion detection method presented aims to raise an alert whenever satellite network signals begin to exhibit anomalous patterns determined by Euclidian distance metric. In line with anomaly-based intrusion detection systems, the method presented relies heavily on building a model of＂normal＂ through the creation of a signal dictionary using windowing and k-means clustering. The results of three signals fi＇om our case study are discussed to highlight the benefits and drawbacks of the method presented. Our preliminary results demonstrate that the clustering technique used has great potential for intrusion detection for non-periodic satellite network signals.

关键词： Intrusion detection irregular data K-means clustering machine learning signal dictionary