86 research outputs found

    Analysis of probability of non-zero secrecy capacity for multi-hop networks in presence of hardware impairments over Nakagami-m fading channels

    Get PDF
    In this paper, we evaluate probability of non-zero secrecy capacity of multi-hop relay networks over Nakagamim fading channels in presence of hardware impairments. In the considered protocol, a source attempts to transmit its data to a destination by using multi-hop randomize-and-forward (RF) strategy. The data transmitted by the source and relays are overheard by an eavesdropper. For performance evaluation, we derive exact expressions of probability of non-zero secrecy capacity (PoNSC), which are expressed by sums of infinite series of exponential functions and exponential integral functions. We then perform Monte Carlo simulations to verify the theoretical analysis.Web of Science25478277

    Secrecy performance enhancement for underlay cognitive radio networks employing cooperative multi-hop transmission with and without presence of hardware impairments

    Get PDF
    In this paper, we consider a cooperative multi-hop secured transmission protocol to underlay cognitive radio networks. In the proposed protocol, a secondary source attempts to transmit its data to a secondary destination with the assistance of multiple secondary relays. In addition, there exists a secondary eavesdropper who tries to overhear the source data. Under a maximum interference level required by a primary user, the secondary source and relay nodes must adjust their transmit power. We first formulate effective signal-to-interference-plus-noise ratio (SINR) as well as secrecy capacity under the constraints of the maximum transmit power, the interference threshold and the hardware impairment level. Furthermore, when the hardware impairment level is relaxed, we derive exact and asymptotic expressions of end-to-end secrecy outage probability over Rayleigh fading channels by using the recursive method. The derived expressions were verified by simulations, in which the proposed scheme outperformed the conventional multi-hop direct transmission protocol.Web of Science212art. no. 21

    How scientific research changes the Vietnamese higher education landscape: Evidence from social sciences and humanities between 2008 and 2019

    Get PDF
    Background: In the context of globalization, Vietnamese universities, whose primary function is teaching, there is a need to improve research performance. Methods: Based on SSHPA data, an exclusive database of Vietnamese social sciences and humanities researchers’ productivity, between 2008 and 2019 period, this study analyzes the research output of Vietnamese universities in the field of social sciences and humanities. Results: Vietnamese universities have been steadily producing a high volume of publications in the 2008-2019 period, with a peak of 598 articles in 2019. Moreover, many private universities and institutions are also joining the publication race, pushing competitiveness in the country. Conclusions: Solutions to improve both quantity and quality of Vietnamese universities’ research practice in the context of the industrial revolution 4.0 could be applying international criteria in Vietnamese higher education, developing scientific and critical thinking for general and STEM education, and promoting science communication

    The Impact of Digital Transformation on Customer Satisfaction to Digital Banking Service of Commercial Banks in Vietnam

    Get PDF
    The present study focuses on examining the interplay and correlation between the digital transformation process as assessed by the digital banking service quality components (Ease of use, Effectiveness, Interoperability, Privacy/ Security, Empathy, Responsiveness, Reliability, Service portfolios, Service charge) and customer satisfaction for digital banking services at commercial banks in Vietnam. The predictors (independent variables) for this study are the aforementioned service quality aspects and moderator is Service charge. The outcome variable (dependent variable) is customer satisfaction. The authors combined qualitative and quantitative research techniques to develop observed variables and assess the model's fit. This study can help banking leaders evaluate and improve the quality of digital banking services in the context of financial liberalization and globalization. Keywords: Digital transformation, Digital Banking, Banking service quality, Customer satisfaction DOI: 10.7176/EJBM/15-6-04 Publication date:March 31st 202

    Liver Involvement Associated with Dengue Infection in Adults in Vietnam

    Get PDF
    Globally, the number of adults hospitalized with dengue has increased markedly in recent years. It has been suggested that hepatic dysfunction is more significant in this group than among children. We describe the spectrum and evolution of disease manifestations among 644 adults with dengue who were prospectively recruited on admission to a major infectious disease hospital in southern Vietnam and compare them with a group of patients with similar illnesses not caused by dengue. Transaminase levels increased in virtually all dengue patients and correlated with other markers of disease severity. However, peak enzyme values usually occurred later than other complications. Clinically severe liver involvement was infrequent and idiosyncratic, but usually resulted in severe bleeding. Chronic co-infection with hepatitis B was associated with modestly but significantly increased levels of alanine aminotransferase, but did not otherwise impact the clinical picture

    Socio-Cultural Factors Challenging Development Interventions in Cattle Production in the Remote Areas of Vietnam

    Get PDF
    The northwest highlands of Vietnam are characterized by high altitude, low infrastructure, and low population densities composed of a wide diversity of different ethnic groups. Their socio-cultural characteristics strongly influence their lifestyle and production systems, including agricultural activities. The majority of these people have suffered from slow economic development, with the highest poverty rate in the country. This is a real need for plausible interventions where behavioral changes of smallholders throughout local value chains would be a critical foundation. Our project implemented in this context of development in the Northwest highlands of Vietnam aims to understand the role of socio-cultural factors in cattle production systems in order to propose and examine feasible technical and marketing interventions to improve local grazing-based cattle production. Data on farmers and other actors (collectors, slaughterhouses, retailers and consumers) in local cattle value chains of two selected provinces (Son La and Dien Bien) were collected at the beginning of the project via a baseline survey. In addition, different group discussions with farmers were conducted until the end of the project to monitor the project’s progress and changes created through its interventions. We found that such behavioral changes cannot be motivated by development interventions per se without integrating an understanding of socio-cultural factors (i.e. ethnicity, geographical location and grazing-practices)

    Static and free vibration analyses of laminated composite shells by cell-based smoothed discrete shear gap method (CS-DSG3) using three-node triangular elements

    Get PDF
    A cell-based smoothed discrete shear gap method (CS-DSG3) using three-node triangular elements was recently proposed to improve the performance of the discrete shear gap method (DSG3) for static and free vibration analyses of isotropic Reissner-Mindlin plates and shells. In this paper, the CS-DSG3 is further extended for static and free vibration analyses of laminated composite shells. In the present method, the first-order shear deformation theory (FSDT) is used in the formulation due to the simplicity and computational efficiency. The accuracy and reliability of the proposed method are verified by comparing its numerical solutions with those of others available numerical results

    A Multistage System for Automatic Detection of Epileptic Spikes

    Get PDF
    A multistage automatic detection system for epileptic spikes is introduced as an assistant tool for epileptic analysis and diagnosis based on electroencephalogram (EEG). The system consists of four stages: preprocessing, feature extraction, classifier and expert system. Multiple state-of-the-art signal processing and machine learning techniques including wavelet transform, spectral filtering, artificial neural network are utilized in order to improve the ability of the overall system stage by stage. Compared to other works, our contributions are three-fold: peaks in the EEG recording are categorized into two groups of non-epileptic spikes and possible epileptic spikes by a committee of three perceptrons; appropriate mother wavelet and wavelet scales are selected for the best system performance; and, based on the neurological fact that an epileptic spike is usually followed by a slow wave, a simple expert system is presented to eliminate pseudo-spikes which are closely analogous to true epileptic spikes. Experimental results show that the proposed system is capable of detecting epileptic spikes efficiently

    Aquilaria yunnanensis S.C. Huang (Thymelaeaceae), A New Record for the Flora of Vietnam

    Get PDF
    Aquilaria yunnanensis S.C. Huang (Thymelaeaceae), known to be endemic to Yunnan, is recorded for the first time from Dong Son Ky Thuong Nature Reserve, Quang Ninh Province, Vietnam. A taxonomic description and DNA analysis based on our Vietnamese collections are presented, together with information on its distribution, habitat and colour photographs
    • …
    corecore