20 research outputs found
Application of the Empirical Mode Decomposition On the Characterization and Forecasting of the Arrival Data of an Enterprise Cluster
Characterization and forecasting are two important processes in capacity planning. While they are closely related, their approaches have been different. In this research, a decomposition method called Empirical Mode Decomposition (EMD) has been applied as a preprocessing tool in order to bridge the input of both characterization and forecasting processes of the job arrivals of an enterprise cluster. Based on the facts that an enterprise cluster follows a standard preset working schedule and that EMD has the capability to extract hidden patterns within a data stream, we have developed a set of procedures that can preprocess the data for characterization as well as for forecasting. This comprehensive empirical study demonstrates that the addition of the preprocessing step is an improvement over the standard approaches in both characterization and forecasting. In addition, it is also shown that EMD is better than the popular wavelet-based decomposition in term of extracting different patterns from within a data stream
Network Coding with Multimedia Transmission and Cognitive Networking: An Implementation based on Software-Defined Radio
Network coding (NC) is considered a breakthrough to improve throughput, robustness, and security of wireless networks. Although the theoretical aspects of NC have been extensively investigated, there have been only few experiments with pure NC schematics. This paper presents an implementation of NC under a two-way relay model and extends it to two non-straightforward scenarios: (i) multimedia transmission with layered coding and multiple-description coding, and (ii) cognitive radio with Vandermonde frequency division multiplexing (VFDM). The implementation is in real time and based on software-defined radio (SDR). The experimental results show that, by combining NC and source coding, we can control the quality of the received multimedia content in an on-demand manner. Whereas in the VFDM-based cognitive radio, the quality of the received content in the primary receiver is low (due to imperfect channel estimation) yet retrievable. Our implementation results serve as a proof for the practicability of network coding in relevant applications
Network Coding with Multimedia Transmission and Cognitive Networking: An Implementation based on Software-Defined Radio
Network coding (NC) is considered a breakthrough to improve throughput, robustness, and security of wireless networks. Although the theoretical aspects of NC have been extensively investigated, there have been only few experiments with pure NC schematics. This paper presents an implementation of NC under a two-way relay model and extends it to two\ua0non-straightforward scenarios: (i) multimedia transmission with layered coding and multiple-description coding, and (ii) cognitive radio with Vandermonde frequency division multiplexing (VFDM). The implementation is in real time and based on software-defined radio (SDR). The experimental results show that, by combining NC and source coding, we can control the quality of the received multimedia content in an on-demand manner. Whereas in the VFDM-based cognitive radio, the quality of the received content in the primary receiver is low (due to imperfect channel estimation) yet retrievable. Our implementation results serve as a proof for the practicability of network coding in relevant applications
The 80-year development of Vietnam mathematical research: Preliminary insights from the SciMath database on mathematicians, their works and their networks
Starting with the first international publication of Le Van Thiem (LĂȘ VÄn ThiĂȘm) in 1947, modern mathematics in Vietnam is a longstanding research field. However, what is known about its development usually comes from discrete essays such as anecdotes or interviews of renowned mathematicians. We introduce SciMathâa database on publications of Vietnamese mathematicians. To ensure this database covers as many publications as possible, data entries are manually collected from scientistsâ publication records, journalsâ websites, universities, and research institutions. Collected data went through various verification steps to ensure data quality and minimize errors. At the time of this report, the database covered 8372 publications, profiles of 1566 Vietnamese, and 1492 foreign authors since 1947. We found a growing capability in mathematics research in Vietnam in various aspects: scientific output, publications on influential journals, or collaboration. The database and preliminary results were presented to the Scientific Council of Vietnam Institute for Advanced Study in Mathematics (VIASM) on November 13th, 2020
Spatiotemporal evolution of SARS-CoV-2 Alpha and Delta variants during large nationwide outbreak of COVID-19, Vietnam, 2021
We analyzed 1,303 SARS-CoV-2 whole-genome sequences from Vietnam, and found the Alpha and Delta variants were responsible for a large nationwide outbreak of COVID-19 in 2021. The Delta variant was confined to the AY.57 lineage and caused >1.7 million infections and >32,000 deaths. Viral transmission was strongly affected by nonpharmaceutical interventions
Safety and efficacy of fluoxetine on functional outcome after acute stroke (AFFINITY): a randomised, double-blind, placebo-controlled trial
Background
Trials of fluoxetine for recovery after stroke report conflicting results. The Assessment oF FluoxetINe In sTroke recoverY (AFFINITY) trial aimed to show if daily oral fluoxetine for 6 months after stroke improves functional outcome in an ethnically diverse population.
Methods
AFFINITY was a randomised, parallel-group, double-blind, placebo-controlled trial done in 43 hospital stroke units in Australia (n=29), New Zealand (four), and Vietnam (ten). Eligible patients were adults (aged â„18 years) with a clinical diagnosis of acute stroke in the previous 2â15 days, brain imaging consistent with ischaemic or haemorrhagic stroke, and a persisting neurological deficit that produced a modified Rankin Scale (mRS) score of 1 or more. Patients were randomly assigned 1:1 via a web-based system using a minimisation algorithm to once daily, oral fluoxetine 20 mg capsules or matching placebo for 6 months. Patients, carers, investigators, and outcome assessors were masked to the treatment allocation. The primary outcome was functional status, measured by the mRS, at 6 months. The primary analysis was an ordinal logistic regression of the mRS at 6 months, adjusted for minimisation variables. Primary and safety analyses were done according to the patient's treatment allocation. The trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12611000774921.
Findings
Between Jan 11, 2013, and June 30, 2019, 1280 patients were recruited in Australia (n=532), New Zealand (n=42), and Vietnam (n=706), of whom 642 were randomly assigned to fluoxetine and 638 were randomly assigned to placebo. Mean duration of trial treatment was 167 days (SD 48·1). At 6 months, mRS data were available in 624 (97%) patients in the fluoxetine group and 632 (99%) in the placebo group. The distribution of mRS categories was similar in the fluoxetine and placebo groups (adjusted common odds ratio 0·94, 95% CI 0·76â1·15; p=0·53). Compared with patients in the placebo group, patients in the fluoxetine group had more falls (20 [3%] vs seven [1%]; p=0·018), bone fractures (19 [3%] vs six [1%]; p=0·014), and epileptic seizures (ten [2%] vs two [<1%]; p=0·038) at 6 months.
Interpretation
Oral fluoxetine 20 mg daily for 6 months after acute stroke did not improve functional outcome and increased the risk of falls, bone fractures, and epileptic seizures. These results do not support the use of fluoxetine to improve functional outcome after stroke
#5 : Associated Factors with Premenstrual Syndrome and Premenstrual Dysphoric Disorder Among Female Medical Students: A Cross-Sectional Study
Background and Aims: Premenstrual syndrome (PMS) and Premenstrual dysphoric disorder (PMDD) are two premenstrual disorders that have been reported in many countries and have gradually become predominant concerns The study aimed to determine potential risk factors associated with PMS and PMDD Method: Three hundred two female student participants who were 18 â 45 years old completed a questionnaire including demographic characteristics, lifestyle factors, and a Vietnamese Premenstrual Syndrome Screening Tool (PSST). We then followed up participants during at least two menstrual cycles using the Daily Record of Severity of Problems (DRSP). The PMS and PMDD diagnosis were established using The Carolina Premenstrual Assessment Scoring System (C-PASS), based on the American College of Obstetrics and Gynecology (ACOG) and Diagnostic and Statistical Manual of Mental Disorders (DSM-5). Results: According to the C-PASS, 35 out of 302 students (11.6%; 95%CI: 8.2-15.7%) met the diagnosis of PMS (31 students) or PMDD (4 students). We found that age at menarche (PR = 0.77, 95%CI: 0.63 - 0.96), having negative Rh blood type (PR=4.43, 95%CI: 1.95 to 10.08), being moderately depressed or higher (PR=2.81, 95%CI: 1.24 to 6.36), and consuming caffeine more than three times per week were statistically associated with having PMS/PMDD after adjusting for other variables. Conclusion: The prominent risk factors for PMS and PMDD were negative Rhesus blood type, menarche age, caffeine consumption, and self-reported depression
Understanding Vietnamese Farmersâ Perception toward Forest Importance and Perceived Willingness-to-Participate in REDD+ Program: A Case Study in Nghe An Province
Climate change continues to pose a constant threat to nature and human beings, and thus demands adaptability and flexibility in forestry and domestic land use management. In this context, the Reducing Emission from Deforestation and Forest Degradation (REDD+) project was introduced to harness forests to curb greenhouse gas emissions in an effort to combat climate change. As of 2020, REDD+ was implemented in 65 countries across the world, including Vietnam. While the missions of afforestation and forest protection cannot be accomplished without the aid of local residents, low participation from stakeholders, particularly poor farmers, is an obstacle in climate mitigation projects. To contribute to improving REDD+ with a useful Vietnam reference, this study uses a random sample approach coupled with a face-to-face interview method to survey 215 households in Chau Thai, one of 206 poor communes in Nghe An province, to learn about (1) residentsâ perception towards the importance of forests, (2) how forests contribute as a source of livelihood, (3) potential for household engagement in REDD+. The research findings show that the important role of forests is well acknowledged, the majority of forestland was allocated to plantation forests, and the seeds are carefully selected to satisfy market demand. In addition, forests are recorded to make major contributions to residentsâ income and roughly four-fifths of households revealed their willingness to get involved in the REDD+ project with a monthly subsidy of 500â2000 kVND (22.3â89.2 USD). The study provides valuable information about forest-based rural livelihood and policy options to facilitate REDD+ participation among farmers. This, in turn, helps devise more appropriate policies for climate change mitigation and sustainable rural mountainous development nationwide and beyond