Optimal Rooftop Photovoltaic System Placement To Minimize Monthly Used Energy Costs For Households In Vietnam’s Cities And Towns

This study presents a strategy to stop paying monthly used energy costs for households in Vietnam’s cities and towns. To get there, the total energy cost acquired from the utility grid must equal the total extra energy supplied to the grid. In addition to the power consumption reduction from the grid for household cus- tomers, the extra energy produced by the rooftop photo- voltaic system (RPV) is sold back to the grid. This mechanism has effectively freed up the monthly en- ergy bill for individual customers. However, the op- timal rated power of the rooftop photovoltaic system (RPV) must first be determined. Two meta-heuristic algorithms, including the Coati optimization algorithm (COA) and the Osprey optimization algorithm (OOA), are implemented to solve the problem. The results obtained by the two algorithms are compared using different criteria. Through these comparisons, OOA completely outperforms COA regarding solution qual- ity and stabilization. For instance, OOA is the only method to reach the best optimal rated power of the RPV. Moreover, OOA is also more effective than COA with 50.17% on mean cost, 11.49% on maximum cost, and 17.06% on standard deviation. By using the solu- tion found by OOA, RPV not only fulfills the house- hold’s needs but also reduces the electric energy cost to zero. While evaluating a five-year operation period, the household can get the benefit of $3,635.64. So, using the RPV is very effective for reaching both economic and environmental benefits

Apply deep learning to improve the question analysis model in the Vietnamese question answering system

Question answering (QA) system nowadays is quite popular for automated answering purposes, the meaning analysis of the question plays an important role, directly affecting the accuracy of the system. In this article, we propose an improvement for question-answering models by adding more specific question analysis steps, including contextual characteristic analysis, pos-tag analysis, and question-type analysis built on deep learning network architecture. Weights of extracted words through question analysis steps are combined with the best matching 25 (BM25) algorithm to find the best relevant paragraph of text and incorporated into the QA model to find the best and least noisy answer. The dataset for the question analysis step consists of 19,339 labeled questions covering a variety of topics. Results of the question analysis model are combined to train the question-answering model on the data set related to the learning regulations of Industrial University of Ho Chi Minh City. It includes 17,405 pairs of questions and answers for the training set and 1,600 pairs for the test set, where the robustly optimized BERT pre-training approach (RoBERTa) model has an F1-score accuracy of 74%. The model has improved significantly. For long and complex questions, the mode has extracted weights and correctly provided answers based on the question’s contents

Burden of diarrheal diseases from biogas wastewater exposure among smallholder farmers in Ha Nam province, Vietnam

Livestock production has developed rapidly in Vietnam in recent years, particularly at the small-scale which account for 65% of the total livestock production. Biogas systems are commonly used to treat livestock waste, however, the health risks from biogas wastewater exposure at smallholder farms are not yet well understood. A quantitative microbial risk assessment approach was applied to estimate the burden of diarrheal diseases from biogas wastewater exposure among 451 smallholder farmers using biogas systems in Ha Nam province. A total of 150 biogas wastewater samples were collected and analysed for E. coli, Giardia, and Cryptosporidium. The study showed that farmers faced diarrheal disease risks due to exposure to biogas wastewater at different exposure scenarios. The calculated annual risk of diarrheal disease by E. coli ranked from 0.15 to 0.21; by Giardia ranked from 0.022 to 0.095; and by Cryptosporidium ranked from 0.006 to 0.015. The estimated diarrheal diseases burden from pathogens in all exposure scenarios largely exceeded the reference level of health outcome target of 10-6DALYs loss per person per year recommended by WHO. The results suggest the importance in reducing concentrations of pathogens in biogas wastewater before use in the fields as a means for mitigating public health impacts

Screening of endophytes from rubber trees (hevea brasiliensis) for biological control of Corticium salmonicolor

28 leaves and living-tissue samples of rubber tree (Hevea brasiliensis) were collected from Ho Chi Minh City, Binh Phuoc province and Binh Duong province (Viet Nam). We isolated and screened endophytes that have potential application as agents for biocontrol of Corticium salmonicolor, the agent of Pink Disease in rubber trees. As a result, 21 strains of endophytic bacteria and 14 strains of endophytic fungi were isolated. Antagonistic activity of the endophytes towards C. salmonicolor was checked by using a dual culture. Testing results showed that: T9, T15 and T16 strains have inhibited C. salmonicolor. T9 and T16 strains showed result that 100% of inhibiting C. salmonicolor at the concentration of 1:1. In the test of ability to kill C. salmonicolor, T9 and T16 strains showed that they could kill C. salmonicolor after 3 sprays of bacterial filtrate. T9 and T6 strains, which were identified by biochemical methods, have similar characteristics to Bacillus thuringiensis

A community participatory intervention model to reduce the health risks from biogas wastewater in Hanam Province, Vietnam

In Vietnam, using biogas to treat livestock waste is common, in particular on small holder farms. However, most small holder farms do not know how to use biogas correctly and wastewater can affect health and the environment. Using a participatory approach with farmers and other stakeholders we developed and implemented a set of interventions in Hanam province to reduce health risks from biogas wastewater. Twenty-four pig farmers were selected as a "core group" to be instrumental in developing the interventions and training other farmers to correctly use biogas. The intervention model was piloted for 6 months. Several outputs were obtained including i) approval and enforcement of a "huong uoc - village law" on environmental protection; ii) training of 24 farmers from the core group in communication skills to share information on using biogas; iii) development of a 6-step program of pig cage cleaning to limit waste loaded to biogas to improve the efficiency of biogas production; iv) a health monitoring books for humans and animals for use by families in the community. The results provided evidence that applying the participatory approach can lead to improved knowledge and practices of farmer using biogas and can reduce the health risks from biogas wastewater

Policy Response, Social Media and Science Journalism for the Sustainability of the Public Health System Amid the COVID-19 Outbreak: The Vietnam Lessons

Vietnam, with a geographical proximity and a high volume of trade with China, was the first country to record an outbreak of the new Coronavirus disease (COVID-19), caused by the Severe Acute Respiratory Syndrome Coronavirus 2 or SARS-CoV-2. While the country was expected to have a high risk of transmission, as of April 4, 2020—in comparison to attempts to contain the disease around the world—responses from Vietnam are being seen as prompt and effective in protecting the interests of its citizens, with 239 confirmed cases and no fatalities. This study analyzes the situation in terms of Vietnam’s policy response, social media and science journalism. A self-made web crawl engine was used to scan and collect official media news related to COVID-19 between the beginning of January and April 4, yielding a comprehensive dataset of 14,952 news items. The findings shed light on how Vietnam—despite being under-resourced—has demonstrated political readiness to combat the emerging pandemic since the earliest days. Timely communication on any developments of the outbreak from the government and the media, combined with up-to-date research on the new virus by the Vietnamese science community, have altogether provided reliable sources of information. By emphasizing the need for immediate and genuine cooperation between government, civil society and private individuals, the case study offers valuable lessons for other nations concerning not only the concurrent fight against the COVID-19 pandemic but also the overall responses to a public health crisis

Genomic serotyping, clinical manifestations, and antimicrobial resistance of non-typhoidal Salmonella gastroenteritis in hospitalized children in Ho Chi Minh City, Vietnam

Nontyphoidal Salmonella (NTS) are among the most common etiological agents of diarrheal diseases worldwide and have become the most commonly detected bacterial pathogen in children hospitalized with diarrhea in Vietnam. Aiming to better understand the epidemiology, serovar distribution, antimicrobial resistance (AMR), and clinical manifestation of NTS gastroenteritis in Vietnam, we conducted a clinical genomics investigation of NTS isolated from diarrheal children admitted to one of three tertiary hospitals in Ho Chi Minh City. Between May 2014 and April 2016, 3,166 children hospitalized with dysentery were recruited into the study; 478 (∼15%) children were found to be infected with NTS by stool culture. Molecular serotyping of the 450 generated genomes identified a diverse collection of serogroups (B, C1, C2 to C3, D1, E1, G, I, K, N, O, and Q); however, Salmonella enterica serovar Typhimurium was the most predominant serovar, accounting for 41.8% (188/450) of NTS isolates. We observed a high prevalence of AMR to first-line treatments recommended by WHO, and more than half (53.8%; 242/450) of NTS isolates were multidrug resistant (MDR; resistant to ≥3 antimicrobial classes). AMR gene detection positively correlated with phenotypic AMR testing, and resistance to empirical antimicrobials was associated with a significantly longer hospitalization (0.91 days; P = 0.04). Our work shows that genome sequencing is a powerful epidemiological tool to characterize the serovar diversity and AMR profiles in NTS. We propose a revaluation of empirical antimicrobials for dysenteric diarrhea and endorse the use of whole-genome sequencing for sustained surveillance of NTS internationally