Lower and upper bound form for outage probability analysis in two-way of half-duplex relaying network under impact of direct link

In this paper, the system performance of the two-way of half-duplex (HD) relaying network under the impact of the direct link is studied. The model system has two sources (S) and one destination (D) communicate by direct link and via relay (R). For system performance analysis, we derived the lower and upper bound for outage probability (OP). Furthermore, the analytical expressions of the system performance are verified by using the Monte Carlo simulation in the effect of main parameters. As shown in the results, we can the simulation and analytical results have a good agreement

Equality in Online Education during COVID-19: Challenging the Educational Needs of Ethnic Minority Students in Vietnam

[Purpose] This study analyzes the inequalities of ethnic minority children to adapt to online education. This is also a challenge to the whole education system in Vietnam before the 4th COVID-19 outbreak is considered to have a serious impact on the economy and society of Vietnam. [Methodology/Approach/Design] A case study is conducted in a cross-sectional form with 50 high school students and 10 teachers of the boarding ethnic minority school in Nam Pu district, Dien Bien province of Vietnam. Questions were conducted for students, teachers, and school administrators. [Findings] The lack of WiFi catchers such as laptops, tablets, and smartphones along with poor infrastructure are the main factors affecting the effectiveness of online learning. [Practical Implications] Equality in education is the sustainable development goal adopted by the United Nations in 2015. Geographical differences and economic conditions are factors that directly impact the effectiveness of students' online learning in the context of COVID-19 19. The Government of Vietnam should have an effective financial policy to provide connectivity for poor students, reducing the gap in access to general education services for online classes that are ethnic minorities.[Purpose] This study analyzes the inequalities of ethnic minority children to adapt to online education. This is also a challenge to the whole education system in Vietnam before the 4th COVID-19 outbreak is considered to have a serious impact on the economy and society of Vietnam. [Methodology/Approach/Design] A case study is conducted in a cross-sectional form with 50 high school students and 10 teachers of the boarding ethnic minority school in Nam Pu district, Dien Bien province of Vietnam. Questions were conducted for students, teachers, and school administrators. [Findings] The lack of WiFi catchers such as laptops, tablets, and smartphones along with poor infrastructure are the main factors affecting the effectiveness of online learning. [Practical Implications] Equality in education is the sustainable development goal adopted by the United Nations in 2015. Geographical differences and economic conditions are factors that directly impact the effectiveness of students' online learning in the context of COVID-19 19. The Government of Vietnam should have an effective financial policy to provide connectivity for poor students, reducing the gap in access to general education services for online classes that are ethnic minorities.[Purpose] This study analyzes the inequalities of ethnic minority children to adapt to online education. This is also a challenge to the whole education system in Vietnam before the 4th COVID-19 outbreak is considered to have a serious impact on the economy and society of Vietnam. [Methodology/Approach/Design] A case study is conducted in a cross-sectional form with 50 high school students and 10 teachers of the boarding ethnic minority school in Nam Pu district, Dien Bien province of Vietnam. Questions were conducted for students, teachers, and school administrators. [Findings] The lack of WiFi catchers such as laptops, tablets, and smartphones along with poor infrastructure are the main factors affecting the effectiveness of online learning. [Practical Implications] Equality in education is the sustainable development goal adopted by the United Nations in 2015. Geographical differences and economic conditions are factors that directly impact the effectiveness of students' online learning in the context of COVID-19 19. The Government of Vietnam should have an effective financial policy to provide connectivity for poor students, reducing the gap in access to general education services for online classes that are ethnic minorities.[Purpose] This study analyzes the inequalities of ethnic minority children to adapt to online education. This is also a challenge to the whole education system in Vietnam before the 4th COVID-19 outbreak is considered to have a serious impact on the economy and society of Vietnam. [Methodology/Approach/Design] A case study is conducted in a cross-sectional form with 50 high school students and 10 teachers of the boarding ethnic minority school in Nam Pu district, Dien Bien province of Vietnam. Questions were conducted for students, teachers, and school administrators. [Findings] The lack of WiFi catchers such as laptops, tablets, and smartphones along with poor infrastructure are the main factors affecting the effectiveness of online learning. [Practical Implications] Equality in education is the sustainable development goal adopted by the United Nations in 2015. Geographical differences and economic conditions are factors that directly impact the effectiveness of students' online learning in the context of COVID-19 19. The Government of Vietnam should have an effective financial policy to provide connectivity for poor students, reducing the gap in access to general education services for online classes that are ethnic minorities

Optimal power generation for wind-hydro-thermal system using meta-heuristic algorithms

In this paper, Cuckoo search algorithm (CSA) is suggested for determining optimal operation parameters of the combined wind turbine and hydrothermal system (CWHTS) in order to minimize total fuel cost of all operating thermal power plants while all constraints of plants and system are exactly satisfied. In addition to CSA, Particle swarm optimization (PSO), PSO with constriction factor and inertia weight factor (FCIWPSO) and Social Ski-Driver (SSD) are also implemented for comparisons. The CWHTS is optimally scheduled over twenty-four one-hour interval and total cost of producing power energy is employed for comparison. Via numerical results and graphical results, it indicates CSA can reach much better results than other ones in terms of lower total cost, higher success rate and faster search process. Consequently, the conclusion is confirmed that CSA is a very efficient method for the problem of determining optimal operation parameters of CWHTS

Power beacon-assisted energy harvesting in a half-duplex communication network under co-channel interference over a Rayleigh fading environment: Energy efficiency and outage probability analysis

In this time, energy efficiency (EE), measured in bits per Watt, has been considered as an important emerging metric in energy-constrained wireless communication networks because of their energy shortage. In this paper, we investigate power beacon assisted (PB) energy harvesting (EH) in half-duplex (HD) communication network under co-channel Interferer over Rayleigh fading environment. In this work, we investigate the model system with the time switching (TS) protocol. Firstly, the exact and asymptotic form expressions of the outage probability (OP) are analyzed and derived. Then the system EE is investigated and the influence of the primary system parameters on the system performance. Finally, we verify the correctness of the analytical expressions using Monte Carlo simulation. Finally, we can state that the simulation and analytical results are the same.Web of Science1213art. no. 257

Nucleotide variation at the methionine synthase locus in an endangered tree species, Fokienia hodginsii (Cupressaceae) in Vietnam

Nucleotide variation at the methionine synthase (MetE) locus within and among populations of an endangered forest tree Fokienia hodginsii in Vietnam was investigated in the present study. A total of 12 populations were sampled across Vietnam. The length of the sequenced locus varied from 1567 to 1559 bp. A total of 42 polymorphic sites were detected among samples. Overall, nucleotide diversity was estimated to be 0.00499 and 0.00692 at the total (ðtot) and silent sites (ðsilent) in the pool, respectively. Nucleotide diversity within populations varied from 0.00300 to 0.00521 at the total and 0.00357 to 0.00666 at silent sites. The estimates of nucleotide diversity were lower in the 4 populations located in central and southern Vietnam (0.00300 to 0.00380) in comparison with the northern populations (ranging from 0.00399 to 0.00543). Overall estimates of genetic differentiation among 12 populations were low (FST = 0.093 and KST* = 0.078), even though both values were highly significant (P < 0.001). Pairwise analysis among 12 populations showed significant genetic differentiation as evaluated by FST and Snn but not significant as evaluated by KST*. Analysis of genetic clustering using BAPS provided the best support for all 144 sequences belonging to the same genetic cluster. The implication of the results revealed in this study in the genetic conservation of F. hodginsii was discussed.Key words: Population genetics, conservation, forest, methionine synthase (MetE), structure

The Performance of ECMWF sub-seasonal forecasts to predict the Rainy Season Onset Dates in Vietnam

The onset of the rainy season is an important date for the mostly rain-fed agricultural practices in Vietnam. Sub-seasonal to seasonal (S2S) ensemble hindcasts from the European Centre for Medium-Range Weather Forecasts (ECMWF) are used to evaluate the predictability of the rainy season onset dates (RSODs) over five climatic sub-regions of Vietnam. The results show that the ECMWF model reproduces well the observed inter-annual variability of RSODs, with a high correlation ranging from 0.60 to 0.99 over all sub-regions at all lead times (up to 40 days) using five different RSOD definitions. For increasing lead times, forecasted RSODs tend to be earlier than the observed ones. Positive skill score values for almost all cases examined in all sub-regions indicate that the model outperforms the observed climatology in predicting the RSOD at sub-seasonal lead times (~28–35 days). However, the model is overall more skilful at shorter lead times. The choice of the RSOD criterion should be considered because it can significantly influence the model performance. The result of analysing the highest skill score for each sub-region at each lead time shows that criteria with higher 5-day rainfall thresholds tend to be more suitable for the forecasts at long lead times. However, the values of mean absolute error are approximately the same as the absolute values of the mean error, indicating that the prediction could be improved by a simple bias correction. The present study shows a large potential to use S2S forecasts to provide meaningful predictions of RSODs for farmers

IMPLEMENT POLICIES ON TRAINING AND FOSTERING CADRES AND CIVIL SERVANTS OF KHMER IN THE MEKONG DELTA, VIETNAM

Cadres and civil servants who are ethnic Khmer people in the Mekong Delta have an essential position and role in implementing the Party's guidelines and guidelines, policies, and laws of the State to present with the people and directly manage society to achieve order, stability, and development. Cadres and civil servants who are ethnic Khmer people are the bridge between the Party, State, and the people, reflecting the people's legitimate thoughts and aspirations for the Party and State. Based on the method of document research, and secondary data, the paper outlines the characteristics of the Khmer people in the Mekong Delta; viewpoints and lines of the Party, policies, and laws of the State on training and retraining policies for cadres and civil servants who are ethnic Khmer people; On the basis of the actual situation of the policy, the thesis has proposed a number of solutions to improve the effectiveness of the policy on training and fostering cadres and civil servants who are ethnic Khmer people in the Mekong Delta.  Article visualizations

Outage performance of underlay cognitive radio networks over mix fading environment

In this paper, the underlay cognitive radio network over mix fading environment is presented and investigated. A cooperative cognitive system with a secondary source node S, a secondary destination node D, secondary relay node Relay, and a primary node P are considered. In this model system, we consider the mix fading environment in two scenarios as Rayleigh/Nakagami-m and Nakagami-m/Rayleigh Fading channels. For system performance analysis, the closed-form expression of the system outage probability (OP) and the integral-formed expression of the ergodic capacity (EC) are derived in connection with the system's primary parameters. Finally, we proposed the Monte Carlo simulation for convincing the correctness of the system performance

Outage probability analysis of EH relay-assisted non-orthogonal multiple access (NOMA) systems over Block Rayleigh Fading Channel

Non-orthogonal multiple access (NOMA) has been identified as a promising multiple access technique for the fifth generation (5G) mobile networks due to its superior spectral efficiency. In this paper, we propose and investigate a Non-Orthogonal Multiple Access (NOMA) of energy harvesting (EH) relay assisted system over Block Rayleigh Fading Channel. In order to evaluate the performance of the proposed system, the integral expression of the outage probability is analyzed and derived. Numerical results confirm that our derived analytical results match well with the Monte Carlo simulations in connection with all possible system parameter

Performance analysis for power-splitting energy harvesting based two-way full-duplex relaying network over nakagami-m fading channel

Energy harvesting relay network is considered as the promising solution for a wireless communication network in our time. In this research, we present and demonstrate the system performance of the energy harvesting based two-way full-duplex relaying network over Nakagami-m fading environment. Firstly, we propose the analytical expressions of the achievable throughput and outage probability of the proposed system. In the second step, the effect of various system parameters on the system performance is presented and investigated. In the final step, the analytical results are also demonstrated by Monte-Carlo simulation. The numerical results demonstrated and convinced the analytical and the simulation results are agreed with each other