检索结果-南通市图书馆

An analytical model for cross-Kerr nonlinearity in a four-level N-type atomic system with Doppler broadening

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2022年第2期31卷 314-319页

作者： Dinh Xuan Khoa nguyen Huy Bang nguyen le thuy an nguyen Van Phu le Van Doai Vinh University 182 Le Duan StreetVinh CityVietna

We present an analytical model for cross-Kerr nonlinear coefficient in a four-level N-type atomic medium under Doppler *** model is applied to87 Rb atoms to analyze the dependence of the cross-Kerr nonlinear coefficient on the external light field and the temperature of atomic *** analysis shows that in the absence of electromagnetically induced transparency(EIT)the cross-Kerr nonlinear coefficient is zero,but it is significantly enhanced when the EIT is *** means that the cross-Kerr effect can be turned on/off when the external light field is on or ***,the amplitude and the sign of the cross-Kerr nonlinear coefficient are easily changed according to the intensity and frequency of the external light *** amplitude of the cross-Kerr nonlinear coefficient remarkably decreases when the temperature of atomic medium *** analytical model can be convenient to fit experimental observations and applied to photonic devices.

关键词： electromagnetically induced transparency Kerr nonlinear effect Doppler effect

Influence of different land-use types on selected soil properties related to soil fertility in A Luoi District,Thua Thien Hue,Vietnam

在线全文

学校读者我要写书评

暂无评论

Soil Ecology letters 2024年第1期6卷 131-140页

作者： Khoa Phuc nguyen Tan Trong Tran Huy Dinh le Phuong thuy nguyen Hien Thao Thi Pham Dien Thanh nguyen Ngu Huu nguyen University of Agriculture and Forestry Hue UniversityHue CityThua Thien Hue 52000Vietnam School of Biotechnology Tan Tao UniversityTan Duc ECityDuc HoaLong An850000Vietnam

Land use type affects the physicochemical properties of *** value of OM and TN is high in acacia *** acidity of soil is considered a serious constraint for *** cash crops are acacia,cassava,banana,rice and *** fertility is affected by land-use types and land management,which exacerbates soil erosion and various other forms of soil degradation in the mountainous regions of *** study was conducted in A Luoi District,Thua Thien Hue,Vietnam to identify the effects of land-use types on specific soil physicochemical characteristics related to soil *** physicochemical properties,such as organic matter(OM),total nitrogen(TN),total phosphorous(TP),and K+were significantly affected by land-use *** results showed that the soils were sandy in rice but clay loam for acacia and *** mean bulk density value of acacia soil was significantly greater than that of other *** were higher in the acacia soils than those in the rice,maize,and banana *** OM content was significantly higher in the acacia,cassava,and banana soils than those in the rice and maize *** mean of exchangeable K+in the rice soil was higher compared to those in other soils and was affected by land-use *** high exchangeable acidity content in the soils was probably due to intensive ***,both land use type and management did not affect the CEC ***,the inappropriate land use caused the disturbance of soil physicochemical properties,indicating that the conditions of rice and maize soils are becoming worse than acacia ***,lowering the intensity of cultivation,adopting incorporated soil fertility management,and applying organic fertilizer should preserve the existing conditions and enhance soil properties.

关键词： Land-use types soil characteristics soil frility suitable crop Vietnam

Development of an experimental method for well-controlled blast induced traumatic limb fracture in rats

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第4期34卷 168-176页

作者： Luyang Xu Xiancheng Yu Clement DFavier Ibidumo Igah thuy-Tien nguyen Warren Macdonald Anthony MJ.Bull Centre for Blast Injury Studies Imperial College LondonLondonUnited Kingdom Department of Bioengineering Imperial College LondonLondonUnited Kingdom Dyson School of Design Engineering Imperial College LondonLondonUnited Kingdom Department of Trauma and Orthopaedics Royal Free London National Health Service Foundation TrustLondonUnited Kingdom

Heterotopic ossification(HO)is a consequence of traumatic bone and tissue damage,which occurs in 65%of military casualties with blast-associated ***,the mechanisms behind blast-induced HO remain *** models are used to study blast-induced HO,but developing such models is challenging,particularly in how to use a pure blast wave(primary blast)to induce limb fracture that then requires an *** studies,including our recent study,have developed platforms to induce limb fractures in rats with blast loading or a mixture of blast and impact ***,these models are limited by the survivability of the animal and repeatability of the *** this study,we developed an improved platform,aiming to improve the animal's survivability and injury repeatability as well as focusing on primary blast *** platform exposed only one limb of the rat to a blast wave while providing proper protection to the rest of the rat's *** obtained very consistent fracture outcome in the tibia(location and pattern)in cadaveric rats with a large range of size and ***,the rats did not obviously move during the test,where movement is a potential cause of uncontrolled *** further conducted parametric studies by varying the features of the design of the *** factors,such as how the limb is fixed and how the cavity through which the limb is placed is sealed,significantly affect the resulting *** platform and test setups enable well-controlled limb fracture induced directly by pure blast wave,which is the fundamental step towards a complete in vivo animal model for blast-induced HO induced by primary blast alone,excluding secondary and tertiary blast *** addition,the platform design and the findings presented here,particularly regarding the proper protection of the animal,have implications for future studies investigating localized blast injuries,such as blast induced brain and lung injuries.

关键词： Blast injury Biomechanics Heterotopic ossification Limb fracture Blast wave Animal model

循环三轴试验加载频率和压实度对重塑砂土液化行为的影响

在线全文

学校读者我要写书评

暂无评论

岩土力学 2024年第6期45卷 1813-1823页

作者： thuy Do Van TIEP Pham Duc HIEU nguyen Van THANG Pham Cao 勒奎东技术大学特殊工程技术研究所越南河内越南航空科技协会越南河内

通过对各向同性固结不排水试样进行循环三轴试验,研究了饱和重塑砂土的液化行为。试验采用恒幅正弦载荷,通过测量剪切模量、阻尼比、轴向应变和超孔隙水压力比的变化,评估了加载频率(分别为0.1、0.5、1.0 Hz)和压实度(分别为0.95、0.90... 详细信息

通过对各向同性固结不排水试样进行循环三轴试验,研究了饱和重塑砂土的液化行为。试验采用恒幅正弦载荷,通过测量剪切模量、阻尼比、轴向应变和超孔隙水压力比的变化,评估了加载频率(分别为0.1、0.5、1.0 Hz)和压实度(分别为0.95、0.90和0.80)对砂土液化行为的影响。试验结果表明,对于压实度为0.95的砂样,在5000次加载循环中,0.1 Hz的加载频率对液化过程影响甚微;而对于压实度为0.90和0.80的砂样,此频率的影响显著。对于压实度为0.80的砂样,当频率增加到0.5 Hz时几乎一加载就直接发生液化。这表明增加加载频率会加快液化速度,而增加压实度则会减慢液化速度。因此,通过一系列的试验可以模拟现场砂土在不同频率下的动荷载条件。试验结果表明,饱和砂土的液化行为由以下因素决定:(1)试样的压实度越低,液化越容易发生;(2)加载频率越高,液化越容易发生;(3)循环轴向应变越大,发生液化所需的循环次数越少;(4)超孔隙水压力随加载循环次数增加,直至试样完全液化。

关键词：液化行为加载频率循环三轴试验饱和固结不排水条件重塑砂土压实度

Is convenience really king? Comparative evaluation of catastrophic costs due to tuberculosis in the public and private healthcare sectors of Viet Nam: a longitudinal patient cost study

在线全文

学校读者我要写书评

暂无评论

贫困所致传染病(英文) 2024年第2期13卷 1-12页

作者： nguyen Hoa Binh Quang Vo Luan nguyen Forse Rachel Jeanette Wiemers Anja Maria Christine Huynh Huy Ba Dong thuy Thi Thu Phan Yen Thi Hoang Creswell Jacob Dang Thi Minh Ha nguyen Lan Huu Shedrawy Jad L?nnroth Knut nguyen Tuan Dinh Van Dinh Luong Annerstedt Kristi Sidney Codlin Andrew James National Lung Hospital Ha Noi Viet Nam Friends for International TB Relief Ha Noi Viet Nam Department of Global Public Health WHO Collaboration Centre On Tuberculosis and Social Medicine Karolinska Institute Stockholm Sweden Stop TB Partnership Geneva Switzerland Pham Ngoc Thach Hospital Ho Chi Minh City Viet Nam

Background In Viet Nam, tuberculosis (TB) represents a devastating life-event with an exorbitant price tag, partly due to lost income from daily directly observed therapy in public sector care. Thus, persons with TB may seek care in the private sector for its flexibility, convenience, and privacy. Our study aimed to measure income changes, costs and catastrophic cost incurrence among TB-affected households in the public and private *** Between October 2020 and March 2022, we conducted 110 longitudinal patient cost interviews, among 50 patients privately treated for TB and 60 TB patients treated by the National TB Program (NTP) in Ha Noi, Hai Phong and Ho Chi Minh City, Viet Nam. Using a local adaptation of the WHO TB patient cost survey tool, participants were interviewed during the intensive phase, continuation phase and post-treatment. We compared income levels, direct and indirect treatment costs, catastrophic costs using Wilcoxon rank-sum and chi-squared tests and associated risk factors between the two cohorts using multivariate *** The pre-treatment median monthly household income was significantly higher in the private sector versus NTP cohort (USD 868 vs USD 578;P=0.010). However, private sector treatment was also significantly costlier (USD 2075 vs USD 1313;P=0.005), driven by direct medical costs which were 4.6 times higher than costs reported by NTP participants (USD 754 vs USD 164;Ple-person household [adjusted odds ratio [(aOR=13.71; 95% confidence interval (CI): 1.36–138.14;P=0.026], unemployment during treatment (aOR=10.86; 95%CI: 2.64–44.60;P<0.001) and experiencing TB-related stigma (aOR=37.90; 95%CI: 1.72–831.73;P=0.021).Conclusions Persons with TB in Viet Nam face similarly high risk of catastrophic costs whether treated in the

关键词： Tuberculosis Patient cost Catastrophic cost Private sector Comparative analysis Viet Nam

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

越南学生汉语近义语气副词习得情况研究

越南学生汉语近义语气副词习得情况研究

作者： nguyen le thuy（阮丽水）吉林大学

学位级别：硕士

语气副词是汉语学界中研究的热点，也是对外汉语教学中的难点。语气副词在汉语中有词义较虚、搭配较灵活、近义词较多等特点，然而这类词语在语气表达方面独有的特性，决定了它在汉语语言运用中极其重要的地位。对许多越南母语学习者来... 详细信息

语气副词是汉语学界中研究的热点，也是对外汉语教学中的难点。语气副词在汉语中有词义较虚、搭配较灵活、近义词较多等特点，然而这类词语在语气表达方面独有的特性，决定了它在汉语语言运用中极其重要的地位。对许多越南母语学习者来说，由于语气副词本身语义比较虚，加之近义词较多，因此，极容易造成理解困难、使用偏误等情况。学习者对这类词的掌握存在较大的困难，因而辨析这类词在教学中显得尤为重要。笔者通过分析在越南语与汉语学习以及应运中遇到的问题，提出了在教学中加入辨析越南语和汉语这类词的设想。因此，我们对周围学习者进行抽样调查，了解到的大体情况，之后对实际的抽样研究以及筛选比较，在此基础上撰写本文。本文从二语习得的角度来研究越南学习者习得近义语气副词的情况。首先，我们在《汉语国际教育用音节汉字词汇等级划分》中选定了16组近义语气副词作为研究对象。通过问卷调查，对结果进行统计，了解越南学习者对近义语气副词的掌握情况。并根据调查的结果与词义用法，分析越南学习者在学习过程中造成偏误的成因，从此提出了教学的建议。全文分为五部分：第一部分，本文以《汉语国际教育用音节汉字词汇等级划分》为研究对象，经查找权威资料，选定调查样本的取词范围为16组近义语气副词（共35个词），并对研究思路与方法进行说明。除此之外，笔者还就前人对语气副词的研究现状的研究成果进行了综合叙述。第二部分，本文通过国内外汉语教学的研究成果以及语言运用情况，预测了越南学习者在学习运用汉语近义语气副词过程中可能出现的偏误情况，针对中高级学习者设计了一份调查问卷，然后运用统计学方法对结果进行了初步分析，得出了这类词语习得情况。第三部分，根据调查结果的统计，运用语言对比分析理论来深究学习者出现的正确和偏误不同的现象，从此找出问题的根源，并进行描写与分类。第四部分，在第三部分的研究基础上，综合总结越南学习者汉语近义语气副词偏误原因，得出了出现偏误主要是由于母语影响的语际偏误与目的语影响的语内偏误的结论。第五部分，提出近义词的教学原则：减少对译释义、加强对比解释、培养语感和词语辨析教学。

关键词： “越南学生” “语气副词” “近义词” “习得研究” “近义语气副词”

A Study on Optimizing the Double-Spine Type Flow Path Design for the Overhead Transportation System Using Tabu Search Algorithm

同方学位论文库评论

在线全文

同方学位论文库

学校读者我要写书评

暂无评论

Intelligent Automation & Soft Computing 2024年第2期39卷 255-279页

作者： nguyen Huu Loc Khuu thuy Duy Truong Quoc Dien le Tran Thanh Cong Vu Hoa Binh Tran Tuong Quan Vo Department of Mechatronics Faculty of Mechanical EngineeringHo Chi Minh City University of Technology(HCMUT)Ho Chi Minh CityVietnam Bach Khoa Research Center for Manufacturing Engineering Ho Chi Minh City University of Technology(HCMUT)Ho Chi Minh CityVietnam VietnamNational University Ho ChiMinh City Ho ChiMinh CityVietnam

Optimizing Flow Path Design(FPD)is a popular research area in transportation system design,but its application to Overhead Transportation Systems(OTSs)has been *** study focuses on optimizing a double-spine flow path design for OTSs with 10 stations by minimizing the total travel distance for both loaded and empty *** employ transportation methods,specifically the North-West Corner and Stepping-Stone methods,to determine empty vehicle travel ***,the Tabu Search(TS)algorithm is applied to branch the 10 stations into two main layout *** results obtained from our proposed method demonstrate a reduction in the objective function value compared to the initial feasible ***,we explore howchanges in the parameters of the TS algorithm affect the optimal *** validate the feasibility of our approach by comparing it with relevant literature and conducting additional tests on layouts with 20 and 30 stations.

关键词： Overhead transportation systems tabu search double-spine layout transportationmethod empty travel flow path design

Emotion Recognition with Capsule Neural Network

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computer Systems Science & Engineering 2022年第6期41卷 1083-1098页

作者： Loan Trinh Van Quang H.nguyen thuy Dao Thi le School of Information and Communication Technology Hanoi University of Science and TechnologyHanoi10000Vietnam Faculty of Information Technology University of Transport and CommunicationsHanoi10000Vietnam

For human-machine communication to be as effective as human-tohuman communication, research on speech emotion recognition is *** the models and the classifiers used to recognize emotions, neural networks appear to be promising due to the network’s ability to learn and the diversity in configuration. Following the convolutional neural network, a capsuleneural network (CapsNet) with inputs and outputs that are not scalar quantitiesbut vectors allows the network to determine the part-whole relationships thatare specific 6 for an object. This paper performs speech emotion recognition basedon CapsNet. The corpora for speech emotion recognition have been augmented byadding white noise and changing voices. The feature parameters of the recognition system input are mel spectrum images along with the characteristics of thesound source, vocal tract and prosody. For the German emotional corpus EMODB, the average accuracy score for 4 emotions, neutral, boredom, anger and happiness, is 99.69%. For Vietnamese emotional corpus BKEmo, this score is94.23% for 4 emotions, neutral, sadness, anger and happiness. The accuracy scoreis highest when combining all the above feature parameters, and this scoreincreases significantly when combining mel spectrum images with the featuresdirectly related to the fundamental frequency.

关键词： Emotion recognition CapsNet data augmentation mel spectrum image fundamental frequency

Building 3-D Human Data Based on Handed Measurement and CNN

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & 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 Information Science Sai Gon UniversityHo Chi Minh70000Vietnam Faculty of Information Technology University of EducationHo Chi Minh70000Vietnam

3-dimension(3-D)printing technology is growing strongly with many applications,one of which is the garment *** application of human body models to the garment industry is necessary to respond to the increasing personalization demand and still guarantee *** paper proposes amethod to construct 3-D human models by applying deep *** calculate the location of the main slices of the human body,including the neck,chest,belly,buttocks,and the rings of the extremities,using pre-existing ***,on the positioning frame,we find the key points(fixed and unaltered)of these key slices and update these points tomatch the current *** add points to a star slice,we use a deep learning model tomimic the form of the human body at that slice *** use interpolation to produce sub-slices of different body sections based on the main slices to create complete body parts *** combine all slices to construct a full 3-D representation of the human body.

关键词： 3-D human model deep learning interpolation