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水声通信信道中的OPNET建模与仿真

东南大学学报（自然科学版） 2014年第3期44卷 477-481页

作者： dao van phuong 左加阔 Bui Thi Oanh 方世良赵力东南大学教育部水声重点实验室南京210003 东南大学移动通信国家重点实验室南京210003

针对水声通信网络信道的实现开销大、复杂性高的特点,提出了一种能够仿真分析水声通信网络的有效方法.该方法分别使用OPNET中的Propagation-Delay-Stage,Receiver-Power-Stage和Background-Noise-Stage三个工具来仿真水声信道中的传播... 详细信息

针对水声通信网络信道的实现开销大、复杂性高的特点,提出了一种能够仿真分析水声通信网络的有效方法.该方法分别使用OPNET中的Propagation-Delay-Stage,Receiver-Power-Stage和Background-Noise-Stage三个工具来仿真水声信道中的传播延迟、发射机功率和水声噪声(水声噪声包括紊流、船运、风波和热噪声).其中,Propagation-Delay-Stage采用MacKenzie速度模型;Receiver-Power-Stage中有Thorp,Schulkin&Marsh和Francois&Garrison 3种传播损失模型.在该方法中,首先仿真比较了取不同传播损失模型时的水声信道,然后根据仿真结果选择一个合适的水声信道,并采用MACAW协议来仿真水声通信网络.最后,通过仿真实验对整个水声通信网络的吞吐量、误码率、丢包率进行了分析.实验结果表明,采用该方法能够有效地仿真水声通信网络.

关键词：水声信道 OPNET 仿真介质访问控制协议

水声通信网络中的MACA-C介质访问控制协议

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信号处理 2014年第9期30卷 1048-1054页

作者： dao van-phuong 赵力左加阔邹采荣东南大学教育部水声信号处理重点实验室江苏南京210096

介质访问控制协议(Medium Access Control,MAC)是水声通信网络中的一种关键技术。与陆地无线通信系统使用无线电波有所不同,水声通信网络依靠水声进行通信。由于水声信道的传播时延长、可用带宽有限,使得设计适合于水声通信网络的MAC协... 详细信息

介质访问控制协议(Medium Access Control,MAC)是水声通信网络中的一种关键技术。与陆地无线通信系统使用无线电波有所不同,水声通信网络依靠水声进行通信。由于水声信道的传播时延长、可用带宽有限,使得设计适合于水声通信网络的MAC协议面临诸多困难。然而,水声信道的长传播时延特性允许在水声信道中同时发送多个数据包,利用该特性,基于MACA协议,本文提出了一种适用于水声通信网络的介质访问控制协议,MACA-C协议。通过将发射数据包和控制包结合在一起,本文提出的协议能够克服水声信道长传输时延的问题。仿真结果表明,MACA-C协议能够提高信道使用率,获得较高且稳定的吞吐量,降低端到端的延迟,并且保持较低的碰撞率。

关键词：水声通信网络 MACA介质访问控制协议水生通信MAC协议水声通信FAMA协议

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自适应语音压缩感知方法

东南大学学报（自然科学版） 2012年第6期42卷 1027-1030页

作者：罗武骏陶文凤左加阔赵力东南大学水声信号处理教育部重点实验室南京210096

针对固定正交基下语音信号稀疏化程度低、适应性差的问题,提出了一种自适应的语音稀疏化方法,并将其应用到语音压缩感知理论中.该方法首先采用线性预测系数的加权线性组合对语音信号进行线性预测,并以线性预测残差基作为信号基.然后,按... 详细信息

针对固定正交基下语音信号稀疏化程度低、适应性差的问题,提出了一种自适应的语音稀疏化方法,并将其应用到语音压缩感知理论中.该方法首先采用线性预测系数的加权线性组合对语音信号进行线性预测,并以线性预测残差基作为信号基.然后,按照稀疏约束条件训练出稀疏表示的过完备字典,并交替应用1-范数稀疏约束的追踪和奇异值分解算法,达到字典与稀疏系数同步更新.该方法从信号特征入手,学习并提取特征或纹理信息,能较好地实现语音信号的稀疏化,提高语音压缩感知的重构性能.实验结果显示,与其他正交基方法相比,该方法的语音稀疏化程度高.语音质量的主客观评价结果显示,该方法具有良好的重构性能.

关键词：压缩感知稀疏性语音线性预测

联合稀疏信号恢复中的分布式路径协同优化算法

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信号处理 2013年第8期29卷 964-970页

作者：左加阔陶文凤包永强方世良赵力邹采荣东南大学教育部水声信号处理重点实验室江苏南京210003 南京工程学院通信工程系江苏南京210003

基于融合中心的多观测向量联合稀疏信号恢复算法需要将各个传感节点的数据传输到融合中心(融合中心可能远离各个节点),该方法在节点功率受限以及缺少融合中心的传感网络中并不适用。为了克服上述困难,本文提出了一种分布式路径协同优化... 详细信息

基于融合中心的多观测向量联合稀疏信号恢复算法需要将各个传感节点的数据传输到融合中心(融合中心可能远离各个节点),该方法在节点功率受限以及缺少融合中心的传感网络中并不适用。为了克服上述困难,本文提出了一种分布式路径协同优化算法来解决上述问题。由于采用了分布式计算和路径协同优化,各个传感节点只需与其近邻节点进行少量的数据交互,每个节点所消耗的传输数据功率和所承受的计算复杂度较低。实验结果表明,本文提出的算法的性能能够很好的逼近基于融合中心的联合稀疏信号恢复算法的性能。

关键词：压缩感知联合稀疏信号恢复多观测向量路径协同优化分布式计算

The COVID-19 pandemic in the ASEAN: A preliminary report on the spread, burden and medical capacities

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Asian Pacific Journal of Tropical Medicine 2020年第6期13卷 247-251页

作者： Minh van Hoang phuong Thi Ngoc Nguyen Thao Thi phuong Tran Long Quynh Khuong An Thi Minh dao Huy van Nguyen Riyanti Djalante Hanh Thi Tuyet Tran Hanoi University of Public Health HanoiVietnam Hanoi Medical University HanoiVietnam Graduate School of Public Health St.Luke's International UniversityTokyoJapan United Nations University-Institute for the Advanced Study of Sustainability(UNU-IAS) TokyoJapan

Objective:To provide preliminary descriptions of the spread,burden and related medical capacity characteristics of the ASEAN ***:We utilized the data from four main official databases,including WHO reports,the Statistics and Research of the Coronavirus Disease,and the Southeast Asia Program of the Center for Strategic and International *** spread of the COVID-19 pandemic,current burden and the COVID-19 medical response capacities were extracted before April 11,***:As of April 13,2020,the ASEAN countries reported19547 COVID-19 positive cases with 817 deaths(case-facility rate of 4.2%).Thailand was the first country in the region that reported having the COVID-19 cases,while Laos was the last to report confirmed COVID-19 *** for the number of deaths to double were between 8-12 *** the testing and treatment capacities,the number of PCR tests provided to the populations was the highest in Vietnam,followed by Singapore,Malaysia,and ***,the percentage of the population being tested was the highest in Brunei(2.31%),followed by Singapore(1.30%).Conclusions:A wide range of interventions were taken into practice in response to the outbreak with an effort of curbing the rise of this ***,special care should not be overlooked as the pandemic is placing a huge impact on the population and becomes increasingly *** tackle the spread of the pandemic in the region,the ASEAN countries should work together as one community to provide better responses to future pandemics and other transboundary public health challenges.

关键词： COVID-19 SARS-CoV-2 ASEAN South-East Asia Epidemiology

Embryonic, genetic and clinical outcomes of fresh versus vitrified oocyte: A retrospective cohort study

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Asian pacific Journal of Reproduction 2023年第6期12卷 266-272页

作者： phuong dao Thi Son Dang Truong Thuan Nguyen Duc Anh Pham van Anh Do Tuan van Hanh Nguyen HP Fertility-Hai Phong International Hospital of Obstetrics and Pediatrics Haiphong180000Vietnam Graduate University of Science and Technology Vietnam Academy of Science and TechnologyHanoi100000Vietnam Institute of Biotechnology Vietnam Academy of Science and TechnologyHanoi100000Vietnam

Objective:To compare embryonic development,ploidy status and clinical outcomes between fresh and frozen-thawed ***:This retrospective cohort study evaluated 83 fertilization cycles including both fresh and frozen oocytes from 79 patients at the HP Fertility Center of Hai Phong International Hospital of Obstetrics and Pediatrics in *** patient underwent several ovarian stimulation cycles to accumulate a certain number of oocytes that would be *** the last oocyte retrieval,all patient’s oocytes including both frozen and fresh would be *** outcomes included the rates of oocyte survival,cleavage embryo,blastocyst,ploidy status,pregnancy,biochemical pregnancy and clinical ***:The oocyte survival rate after thawing was 96.5%.No statistically significant difference was found when comparing fresh and frozen oocytes regarding fertilization rate(78.1%vs.75.5%,P=0.461),usable cleavage embryo rate(86.9%vs.87.2%,P=0.916)but usable blastocyst rate was found higher statistically in the frozen oocyte group(44.4%vs.54.0%,P=0.049).The percentages of euploid,aneuploid and mosaic embryos between the fresh group and the vitrified group had no significant differences(33.8%vs.31.6%,P=0.682;51.0%vs.54.2%,P=0.569;15.2%vs.12.4%,P=0.787;respectively).The rates of pregnancy,biochemical pregnancy and clinical pregnancy had no statistical difference(68.8%vs.64.8%,P=0.764;12.5%vs.3.6%,P=0.258;37.5%vs.46.4%,P=0.565).17 Mature oocytes are the minimum to have at least one euploid ***:Oocyte vitrification does not affect embryonic,genetic and clinical *** number of mature oocytes should be considered for fertilization in some cases.

关键词： Clinical outcomes Embryonic development Genetic outcomes Human oocyte Oocyte accumulation Oocyte cryopreservation Ploidy status Vitrified oocyte

Anti-inflammatory effects of alkaloid enriched extract from roots of Eurycoma longifolia Jack

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Asian Pacific Journal of Tropical Biomedicine 2019年第1期9卷 18-23页

作者： dao Thi Thanh Hien Tran Phi Long Tran phuong Thao Jeong-Hyung Lee Duong Thu Trang Nguyen Thi Thu Minh Pham van Cuong Do Thi Ngoc Lan Nguyen Hai Dang Nguyen Tien Dat Deparment of Traditional Pharmacy Hanoi University of Pharmacy Department of Biochemistry College of Natural Sciences Kangwon National University Advanced Center for Bio-organic Chemistry Institute of Marine Biochemistry Vietnam Academy of Science and Technology National Institute of Drug Quality Control Center for Research and Technology Transfers

Objective: To examine the in vitro and in vivo anti-inflammatory effects of the alkaloid enriched extract(ELA) from the roots of Eurycoma longifolia. Methods: The in vitro antiinflammatory effects of ELA were evaluated by examining its inhibitory activities against nitric oxide(NO) production and inducible nitric oxide synthase(iN OS) and cyclooxygenase2(COX-2) expressions in lipopolysaccharide(LPS)-stimulated RAW264.7 cells. The level of NO produced in the culture media was determined by Griess method. The i NOS and COX-2 protein expressions were analyzed by Western blot. The in vivo effect of ELA was evaluated on LPS-induced septic shock in mice model. Mice mortality was monitored for5 days after injection of LPS. The chemical contents of the ELA were determined by using various chromatographic and spectroscopic techniques. Results: The ELA was found to exhibit a significant anti-inflammatory effect in both in vitro and in vivo models. The results demonstrated that ELA dose-dependently inhibited LPS-induced NO production as well as the protein iN OS and COX-2 expressions. In the septic shock model, ELA dose-dependently protected mice from LPS-induced mortality. Further study on the isolated components of ELA indicated that 9,10-dimethoxycanthin-6-one may contribute significantly to the antiinflammatory effects of the extract. Conclusions: These results suggest that ELA exhibits the anti-inflammatory activity via suppression of pro-inflammatory mediators such as NO, iN OS,and COX-2 and protects mice from LPS-induced mortality in septic shock model.

关键词： Eurycoma longifolia Anti-inflammation Alkaloid 9,10-dimethoxycanthin-6-one

In vivo anticancer activity of maesopsin 4—O— β—glucoside isolated from leaves of Artocarpus tonkinensis *** Gagnep

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Asian Pacific Journal of Tropical Medicine 2016年第4期9卷 343-348页

作者： Trinh Thi Thuy dao Duc Thien Tran Quang Hung Nguyen Thanh Tam Nguyen Thi Hoang Anh Nguyen Thi Nga Nguyen Thi Cuc Le phuong Mai Tran van Sung Domenico V.Delfino Do Thi Thao Institute of Chemistry.Vietnam Academy of Science and Technology Institute of Biotechnology Vietnam Academy of Science and Technology National Research Council Canada Measurement Science and Standards1200 Montreal RoadBuilding M-12.Ottatca.Ontario KIA OR6 Department of Medicine University of PerugiaPiazzale Gambuli.S.Andrea delle Fratte

Objective:To investigate the antitumor effect of maesopsin 4-O-β-glucoside(TAT2) isolated from the leaves of Artocarpus tonkinensis(***) *** ***:The antitumor activity of TAT2 was evaluated in Lewis lung carcinoma(LLC) tumor-bearing ***/c mice had tumors induced by implantation with 2× 10~6 LLC cells into the subcutaneous right posterior ***-bearing mice were treated orally with a range of doses of TAT2 and a standard drug,*** were observed for tumor growth and mortality *** was collected to determine hematological and biochemical *** TAT2 was isolated from an ethanolic extract of *** *** structure was determined by MS and NMR spectroscopy,and identified as *** compound did not show acute toxicity at the highest dose tested(2 OIK) mg/kg body weight).TAT2 exhibited antitumor activity by decreasing tumor growth,increasing the survival rale,and ameliorating some hematological and biochemical parameters at doses of 100 and 200 mg/kg body weight(P<0.05).Conclusions:These results indicate that TAT2 possesses clear antitumor *** to its bioavailability and low toxicity,and the fact that it could be isolated in a large scale from *** leaves,the compound shows promise as a potential anticancer drug.

关键词： Artocarpus tonkinensis BALB/c Hematological parameters Lewis lung carcinoma Maesopsin 4-0-β-glucoside

Protein profile of symbiotic bacteria Mesorhizobium loti TONO

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Protein profile of symbiotic bacteria Mesorhizobium loti TON...