Concepts of Agri-Competitiveness in Theorical and Imperical Researchs

The purpose of this study is to analyze the competitiveness of exported agricultural products through theoretical and empirical studies, estimation methods and determinants. Not only summarizing the competitiveness theories of agricultural products exported from previous studies, the article also clarifies the concept of competitiveness of agricultural products at the level of products/services, firms/ farms, industry, thereby helping firms from agricultural countries - which rely heavily on agricultural production and agricultural products export to find the right ways to identify definitions and concepts, then choose the right methods of measurement, compare its export agricultural products competitiveness. Since, the study also proposed the use of synthetic indicators to measure the competitiveness of agricultural exports which is an important basis for the state agencies in the study and propose their export policy of agricultural products in the near future

Investigation of 1d Photonic Crystal Based on Nano-porous Silicon Multilayer for Optical Filtering

We present the fabrication, simulation, and measurements of 1D photonic crystal based on nano-porous silicon multilayer designed as an optical interference filter. Using electro-chemical etching with timely repeat steps of applied current densities, we fabricated a multilayer structure composed of alternating high- and low-index layer which achieved 90% power reflectivity at wavelength range of 1400-3000 nm. The simulation is relying on the Transfer Matrix Method (TMM) to design and predict the optical properties of nano-porous silicon multilayer as well as the relation between anodization parameters with reflection spectra. The measured reflection and transmission spectra of the nano-porous silicon multilayer show good agreement with simulation. This technique could provide a convenient and economical method to produce filters, cavities, and graded-index dielectric waveguides in the future

ARISTOTLE’S EDUCATIONAL IDEAS

Aristotle (384-322 BC) was a great thinker, an encyclopedic brain of ancient Greek science and philosophy. Perhaps few people know him as an educator who brought out extremely deep opinions about subjects, program contents, role of education, etc. nearly 2500 years ago. In all his researching life, he has many scientific works that are meticulous and scientifically valuable aimed at bringing “the best things” for humans. In the book Politics - although educational ideas are not the main contents of the book, they are presented quite closely by Aristotle – positive factors are included and have been very important up to now.  Article visualizations

Chemical composition and antimicrobial activity of the essential oil from leaves of Magnolia coriacea (Hung T. Chang & B. L. Chen) figlar growing in Vietnam

Leaf essential oil of Magnolia coriacea (Hung T. Chang B. L. Chen) Figlar growing wild in the Bat Dai Son Nature Reserve, Ha Giang Province, Viet Nam was obtained by hydrodistillation and its chemical composition was analyzed using GC/MS. In total, 45 compounds were detected in the essential oil, accounting for 87.1% of the oil, in which 37 compounds were identified accounting for 66.9%. Bicyclogermacrene (12.6%) and spathulenol (17.0%) were the main components of the leaf essential oil of M. coriacea. Antimicrobial activity of the essential oil sample was tested against three microorganism strains using an agar disk diffusion method. The results show that the inhibitory zone diameters ranged from 8.5 to 20.5 mm. Median inhibitory concentration (IC50) and minimum inhibitory concentration (MIC) of the essential oil was determined using microdilution broth susceptibility assay against seven test microorganism strains. Bacillus subtilis had the highest sensitivity with IC50 and MIC values of 185.9 and 512 µg/mL, respectively. 

Preschool STEM Activities and Associated Outcomes: A Scoping Review

This review highlights the need for further investigation into the benefits of STEM activities in preschool children’s learning, girls’ engagement and learning of children with disabilities in the STEM field. The review process involved accessing 19 relevant studies from Scopus, ERIC and Google Scholar databases in March 2023. Through the synthesis of information from these studies, seven STEM activities were identified as effective in enhancing preschool children’s learning: educational robots, educational games, argumentative interactions, inquiry-based learning and engineering design, drawing and telling about engineers, free play and pretend play, and group membership. Each of these activities contributes to different learning outcomes for children. Moreover, the review emphasizes the importance of role-playing activities ‘as if’ engineers and scientists, facilitated by teachers, in fostering girls’ motivation and engagement in the STEM field from an early age. Long-term scientific interventions at home have a significant positive impact on the science literacy skills of deaf children. The implications of this review are particularly relevant for early childhood educators, as it provides valuable insights into the use of STEM activities to enhance children’s learning outcomes

An effective method for clustering-based web service recommendation

Normally web services are classified by the quality of services; however, the term quality is not absolute and defined relatively. The quality of web services is measured or derived using various parameters like reliability, scalability, flexibility, and availability. The limitation of the methods employing these parameters is that sometimes they are producing similar web services in recommendation lists. To address this research problem, the novel improved clustering-based web service recommendation method is proposed in this paper. This approach is mainly dealing with producing diversity in the results of web service recommendations. In this method, functional interest, quality of service (QoS) preference, and diversity features are combined to produce a unique recommendation list of web services to end-users. To produce the unique recommendation results, we propose a varied web service classification order that is clustering-based on web services’ functional relevance such as non-useful pertinence, recorded client intrigue importance, and potential client intrigue significance. Additionally, to further improve the performance of this approach, we designed web service graph construction, an algorithm of various widths clustering. This approach serves to enhance the exceptional quality, that is, the accuracy of web service recommendation outcomes. The performance of this method was implemented and evaluated against existing systems for precision, and f-score performance metrics, using the research datasets

Effect of Excitation Migration and Upconversion in Highly Erbium-doped Glass Micro-sphere Lasers

Excitation migration and upconversion process in the Erbium-doped silica-alumina glass microsphere lasers with concentrations of 2500-4000~ppm were investigated in detail. The experiment shows that under 976~nm excitation, the intense of up-conversion emission at 523, 546 and 657~nm, corresponding to the transitions $^{2}$H$_{11 / 2 } \to ^{4}$I$_{15 / }$, $^{4}$S$_{3 / 2} \to ^{4}$I$_{15 / 2}$, and $^{4}$F$_{9 / 2} \to ^{4}$I$_{15 / 2}$, respectively, $^{ }$depends on the erbium content, migration of excitation and pump power. The excitation migration has strongly influenced on the threshold and Red shift of lasing wavelength and migration-assisted up-conversion process leads to degraded amplification performance of microsphere lasers made by silica-alumina glasses with different contents of Er-ions

EVALUATION OF BIODEGRADATION RATE CONSTANT (K₁) AND BOD POLLUTION IN THE LAKE SYSTEM OF HANOI

Joint Research on Environmental Science and Technology for the Eart

Numerical calculating linear vibrations of third order systems involving fractional operators

This paper presents a numerical method for dynamic calculation of third order systems involving fractional operators. Using the Liouville-Rieman's definition of fractional derivatives, a numerical algorithm is developed on base of the well-known Newmark integration method to calculate dynamic response of third order systems. Then, we apply this method to calculate linear vibrations of viscoelastic systems containing fractional derivatives