53 research outputs found
Software-Defined Networks: Architecture for Extended SDN Applications and Resource Optimization in Cloud Data Centers
University of Technology Sydney. Faculty of Engineering and Information Technology.Virtualization is the main mechanism to share resources to many customers by creating virtual resources on the common physical resources. The challenge is to search for an optimal resource allocation mechanism that maximizes the capacity of the virtual resources. Network virtualization needs a new virtual network embedding (VNE) mechanism that focuses concurrently on control congestion, cost saving, energy saving; a link embedding mechanism needs to select actively based on multiple objectives the physical link resources, network slicing requires a new resource allocation mechanism that satisfies latency constraints of 5G mobile system. This research investigated and developed solutions for resource request delivery, and optimal resource allocation in network virtualization and 5G core network slicing applying SDN technology.
In the research, firstly, the three-tier architecture applying micro-service architecture for extended SDN application is presented to facilitate the flexibility, in which new services are created or composed, existing services are reused. The evaluation is the prototype of the Dynamic resource allocation using the proposed architecture.
Secondly, the multiple-objective VNE that focuses on congestion avoidance, energy saving and cost saving (CEVNE) is presented. The novelty lies in the CEVNE mathematical model for multiple-objective optimization problems, and its nodes and link embedding algorithms. The evaluation showed that CEVNE outperformed The-State-Of-The-Art in acceptance ratio in the challenged, near-congestion scenarios.
Thirdly, the architecture to realize virtual link mapping in CEVNE is presented. The novelty is in the SDN-based heuristic algorithm, and the applying of the architecture for extended SDN applications. The research results in the realization of the active virtual link embedding process that focuses on multi-objective concurrently. The evaluation showed that the solution outperformed the traditional link mapping in all three objectives.
Fourthly, the mathematical model of the resource allocation optimization in latency-aware 5G core network slicing is presented. The novelties lie in the satisfaction of different latency requirements of 5G applications: eMBB, uRLLC, and mMTC, and the solution strategy to linearize, convex-relax and decompose the program into sub-problems. The evaluation shows that the solution outperformed the The-State-Of-The-Art in resource allocation, execution time, latency satisfaction and the arrival rates.
In this thesis, the resource optimization problem and the architecture for extended SDN applications have been studied comprehensively. The results of this thesis can readily be applied to 5G vertical applications where resource optimization and network routing problems exist naturally in multiple domains and require software defined networking logically centralized control architecture for efficient and dynamic solutions
Exploiting Idioms and Proverbs of Vietnamese Regions in Teaching Mathematics in Primary Schools
Mathematics and idioms, as well as proverbs, all reflect the laws of life. At the same time, primary school children may have heard idioms and proverbs before attending school. Therefore, there are many possibilities to exploit and apply idioms and proverbs in teaching mathematics in primary schools. This study aims to identify appropriate situations and apply idioms and proverbs in different regions of Vietnam to teaching mathematics. The researchers selected 1155 expressions related to mathematics from many typical pieces of research on idioms and proverbs in Vietnam. After surveying 1822 teachers three times in many provinces and cities in all 3 regions of Vietnam: the North, the Central and the South, the researchers have classified the data according to the criteria from closed to open-ended questions. The results show a prominent level of interest (level 4/5) of all teachers participating in the survey, and there is no difference in the effectiveness in the three regions, but there is a clear difference in regions in using idioms and proverbs. Particularly, identifying situations to teach geometric and quantitative knowledge, as well as probability and statistics, allows one to apply idioms and proverbs at a high level. It is concluded that if idioms and proverbs from Vietnamese regions are appropriately selected and applied in teaching mathematics in primary schools, they will contribute to improving students' mathematical ability and preserving the national cultural heritage. Doi: 10.28991/ESJ-2022-SIED-015 Full Text: PD
Impacts of Economic Development on the Awareness of Cultural Preservation of Ethnic Minority People in the Border Region of Northern Vietnam
Purpose: The aim of this study is to examine how the Vietnamese government's economic development strategies affect ethnic minority people's knowledge of cultural preservation in the border area of Northern Vietnam.
Theoretical framework: The study focuses on three main driven factors of the awareness of cultural preservation that are economic changes, societal changes, and environmental changes from three economic fields: agriculture, industry, and trade and services.
Design/methodology/approach: The research sample was taken from ethnic minorities in Northern Vietnam's border area. For questionnaire administration, interviewees are selected at random from the population. Face-to-face, drop-off, and phone-calling approaches were used to disseminate the questionnaire. We received 544 completed returns out of 725 surveys sent out. The data was then cleaned and analyzed with SPSS 20 software using Partial Least Squares Structural Equation Modelling (PLS-SEM).
Findings: The results of a study of ethnic minority communities in seven provinces in Northern Vietnam's border region show that the development of agriculture, industry, trade and service significantly impacts ethnic minority people's awareness of cultural preservation issues due to environmental changes. In contrast, economic and sociological developments appear to have little influence on ethnic minority people's attention to cultural preservation. This phenomenon may be due to the long-term effects of economic and sociological changes, which mostly affect intangible cultural heritages. In contrast, environmental impats are felt swiftly and primarily on physical cultural heritages that can be seen.
Research, Practical & Social implications: The findings of the research provide policymakers with valuable insights on the effects of economic development on cultural preservation. The study's recommendations can inform policies that promote sustainable economic development while preserving the cultural heritage of ethnic minority communities.
Originality/value: The research focuses on the border region of Northern Vietnam, which is an area of strategic importance for economic development and cultural preservation. The study's unique focus on this region provides insights into the cultural and economic dynamics of a specific area that has not been extensively studied
Teaching practicum: The impacts on classroom management skills of novice lecturers
This research investigates the perspectives of the novice lecturers in the Faculty of English Language Teacher Education (FELTE) regarding Teaching Practicum’s impacts on their classroom management skills. Using survey research, data was gathered through questionnaires distributed among the whole population of 29 participants, followed by semi-structured interviews to gain a deeper insight into participants’ experience. The study’s results showed that novice lecturers generally made considerable progress in classroom management skills, especially in attention-drawing and response encouragement, creation of a motivating environment as well as physical and emotional interactions with students. On the other hand, it was discovered that inadequate duration and inappropriate timing generally impeded novice lecturers’ gains during their Teaching Practicum. However, some challenges related to supervisor and school choice turned out to be significant factors from which participants could derive considerable benefits, which is opposed to previous research. At the end of the study, some recommendations were suggested for future research on this topic
Behavioral Improvements and its Molecular Mechanism of Ilex kudingcha C.J. Tseng on Animal Model of Alzheimer’s Disease
Alzheimer's disease (AD) is a common chronic neurodegenerative disease with well-defined pathophysiological mechanisms. Ilex kudingcha (IK) C.J. Tseng is commonly known as bitter tea or “Khom” tea in Vietnam. The present study was conducted to investigate the anti-dementia effect of IK using olfactory bulbectomized (OBX) mice. OBX mice were daily treated with IK extract (540 mg/kg) or reference drug, tacrine (2.5 mg/kg) 1 week before and continuously for 3 days after the OBX surgery. The object recognition test, modified Y maze test and fear conditioning test were employed to analyze non-spatial short-term, spatial short-term and long-term memories of the mice respectively. Administration of IK extract and tacrine attenuated these OBX-induced cognitive deficits in mice. The effects of IK and tacrine on spatial short-term memory impairment were reversed by scopolamine, a muscarinic receptor antagonist. The amyloid-beta (Aβ) production in adult transgenic Drosophila brain flies was also investigated by using Western blotting with APP-HA antibody. These results indicated that IK extract improves short-term and long-term memory disturbances in OBX mice and that muscarinic receptor may play a role on these actions. In addition, our result also showed that IK extract reduces the expression of amyloid precursor protein (APP) in brain of AD model using Drosophila melanogaster
Depth-dose distribution in potatoes with low-energy X-rays
Irradiation is known as a handful measure to inhibit potato sprouting, kill harmful bacteria, and increase preservation. The absorbed dose is one of the essential characteristics of the irradiation process. In this study, the depth-dose distributions in potatoes and polymethyl methacrylate were investigated under low-energy X-ray irradiation by using the Fricke dosimeter and Gafchromic film dosimeter. The dose rates required for the rays to penetrate in polymethyl methacrylate were compared with those in potatoes. Polymethyl methacrylate could be used as a phantom in measuring the depth dose delivered in potatoes. The difference in depth-dose distribution in potatoes between one-sided and double-sided irradiation was also investigated. The calculated dose uniformity ratio values are 5.8 and 1.9 for potatoes irradiating one-sided and double-sided
Adsorption of ammonium, nitrite, and nitrate onto rice husk biochar for nitrogen removal
This study aims to investigate the adsorption capacity of ammonium NH4+, nitrite NO2- and nitrate NO3- onto rice husk biochar (RHB) obtained from 550 °C pyrolysis temperature in the context of using low-cost absorbent for recirculating aquaculture system (RAS). Raw RHB at its original size 5–8 mm has been choosen for testing its adsorption capacity as well as several key material properties (pHPZC, surface area, and elemental analysis). From surface functional group analysis, there existed the O–H group (at frequency 3443 cm-1), –CH3 (2360 cm-1), and either –C=O or C=C group (in the range of frequency 1600–1650 cm-1) as well as –COOH (1456 cm‒1) that helped enhance chemical adsorption. The experimental adsorption data has been roughly consistent with Langmuir and Freundlich models that used to calculate the maximum saturated monolayer adsorption capacity Q0max of ammonium, nitrite, and nitrate were 0.1003, 0.2477, and 0.1290 mg/g respectively. Therefore, RHB could be a potential candidate for biofilter application in both targets cost-efficient and sustainable that worth applied at scale
Successful Treatment of Facial Atrophic Acne Scars by Fractional Radiofrequency Microneedle in Vietnamese Patients
AIM: The aim of this study was to evaluate the effect of the fractional Radiofrequency microneedle treatment for facial atrophic acne scars.
METHODS: A group of 52 patients were recruited for the study. Goodman & Baron’s acne scar grading system was used for assessment at their first visit and at the end of 3 months after the last treatment session.
RESULTS: The results displayed that 73.1% of patients have the improvement of the Goodman scar level after four times treatment. The Goodman and Baron scar point mean was reduced from 16 ± 7.6 to 5.6 ± 5.0 (p < 0.01). Post-inflammatory hyperpigmentation was experienced in 5 patients (9.6%).
CONCLUSION: The microneedle fractional Radiofrequency is an effective treatment method of facial atrophic acne scars, with minor side effects and a short down-time
PHÁT HIỆN MỘT SỐ THUỐC HẠ GLUCOSE MÁU TRỘN LẪN TRONG CHẾ PHẨM DƯỢC LIỆU BẰNG PHƯƠNG PHÁP SẮC KÝ LỎNG HIỆU NĂNG CAO (HPLC)
Circular No. 10/2021/TT-BYT stipulated that several hypoglycemic drugs, such as metformin hydrochloride, are prohibited from adulterating medicinal herbal preparations. Therefore, this study aims to develop a procedure to detect five hypoglycemic drugs, including metformin hydrochloride, glibenclamide, gliclazide, glimepiride, and glipizide, adulterated in herbal preparations by using the high-performance liquid chromatography (HPLC) method. The chromatographic program includes the methanol:phosphate buffer pH 3 mobile phase 70/30 (v/v), chromatographic column C18 (250 × 4.6 mm, 5 μm), and analysis time of 25 minutes. The procedure has high specificity, accuracy and precision, according to AOAC. We detected six herbal products reacting positively with glibenclamide and one with both metformin hydrochloride and glibenclamide.Thông tư số 10/2021/TT-BYT quy định một số thuốc hạ glucose máu, như metformin hydroclorid, là các chất cấm trộn lẫn trong chế phẩm có nguồn gốc từ dược liệu. Do đó, mục tiêu nghiên cứu này là xây dựng quy trình phát hiện năm loại hoạt chất hạ glucose máu, gồm metformin hydroclorid, glibenclamid, gliclazid, glimepirid và glipizid, trộn lẫn trong chế phẩm có nguồn gốc dược liệu bằng phương pháp sắc ký lỏng hiệu năng cao (HPLC). Chúng tôi đã xây dựng được chương trình sắc ký gồm hệ pha động methanol:đệm phosphat pH 3 với tỷ lệ 30/70 (v/v), cột sắc ký C18 (250 × 4,6 mm, 5 μm), và thời gian phân tích 25 phút. Phương pháp thẩm định có tính đặc hiệu cao, độ đúng, độ lặp lại và độ tái lặp cao, đạt yêu cầu theo AOAC. Chúng tôi đã phát hiện bảy mẫu chế phẩm dược liệu dương tính trong đó sáu mẫu dương tính với glibenclamid và một mẫu dương tính đồng thời với metformin và glibenclamid
Study on total lipid content, lipid class composition of some fire and soft corals collected in Nha Trang, Vietnam
For the first time, the total lipid content and lipid class composition of the Vietnamese soft corals (Sinularia brassica, Sinularia flexibilis) and fire corals (Millepora dichotoma, Millepora platyphylla) were investigated. The results indicated that the total lipid content of the investigated species was significantly different. Compositions of the lipid classes were analyzed using TLC and image analysis program Sorbfil TLC Videodensitometer DV and the results showed that phospholipids (PL, 10.91–16.02%), monoalkyldiacylglycerols (MADAG, 20.69-39.92%) and hydrocarbon wax (HW, 29.83-37.17%) were the main lipid classes of the total lipid in soft coral species. Meanwhile, PL (24.11-33.23%), TG (14.27–34.92%), ST (10.10–14.50%) and HW (12.08–19.95%) were predominant in fire coral species. ST, TG and FFA contents in soft and fire corals were at low level. DG was only present in the Sinularia flexibilis but not in other studied corals
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