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Maintaining a balanced neutral point, reducing power loss, execution time are important criteria for the controlling of neutral point clamped (NPC) inverter. However, it is tough to meet all the challenges and also supplying the load current within the harmonic limit. This paper aims to maintain load current quality within the Institute of Electrical and Electronics Engineers 519 standard and meet the above-mentioned challenges.

The output load current of a three-level simplified neutral point clamped (3 L-SNPC) inverter is controlled in this paper using model predictive control (MPC). The 3 L-SNPC inverters is considered because fewer semiconductor devices are used in this topology; this will enhance the reliability of the system. MPC is used as a controller because it can handle the direct current-link capacitors’ voltage balancing problem in a very intuitive way. The proposed 3 L-SNPC yields similar current total harmonic distortion (THD), transient and steady-state responses, voltage stress and over current protection capability as the conventional NPC inverter. To reduce the computational burden of the proposed SNPC system, two simplified MPC strategies are proposed, namely, single voltage vector prediction-based MPC and selective voltage vector prediction-based MPC.

The system shows a current THD of 2.33% at 8.96 kHz. The overall loss of the system is reduced significantly to be useful in medium power applications. The required execution times for the simplified MPC strategies are tested on the hardware dSPACE 1104 platform. It is found that the single voltage vector prediction-based MPC and the selective voltage vector prediction-based MPC are computationally efficient by 8.28% and 62.9%, respectively, in comparison with the conventional MPC-based conventional NPC system.

Multiple system constraints are considered throughout the paper and also compare the SNPC to the conventional NPC inverter. Proper current tracking, over-current protection, overall power loss reduction especially switching loss and maintaining capacitor voltages balance at a neutral point are achieved. The improvement of execution time has also been verified and calculated using hardware-in-loop of the dSPACE DS1104 platform.

Predictive current control (PCC) of three-to-five-phase direct matrix converters (DMCs) is computationally expensive. For this reason, this study aims to consider a reduced number of switching states of DMC in PCC algorithm to predict the control objectives, such as output current control and input reactive power control.

The switching sequences which yield the voltage vectors of variable amplitude at a constant frequency in space are considered for the prediction and optimization step of PCC algorithm. For the selected voltage vectors, the phase angles of the output vectors are independent on the phase angles of the input vectors. In a three-to-five-phase DMC, there are 243 valid switching states. Among the switching states, only 91 states are considered using the aforementioned concept of variable amplitude output at a constant frequency. This reduced number of switching states simplifies the computational complexity of MPC based current control of three-to-five-phase DMC.

The computational complexity of the proposed PCC based DMC is lower than the all 243 vectors based PCC. The current total harmonic distortion, transient current response and input reactive power control for the simplified 91 vector based PCC are similar to the all 243 vectors based PCC.

A reduced number of switching sequence is considered for the prediction and optimization step of PCC algorithm. Hence, PCC algorithm can be sampled at a high frequency in real-time applications. Then, the performance of the PCC will be improved.

The main purpose of this paper is to find out the perception of different respondents' groups related to the factors that influence the online learning for higher education in Bangladesh during the COVID-19 pandemic.

A survey through a structured questionnaire was conducted to gather qualitative information from the 250 respondents (university students, faculty members and administrative officers) in Bangladesh. A questionnaire has been used for collecting primary data, which have been selected using the justification method under the non-probability sampling technique.

The findings of this study indicated that majority of the respondents told that online classes could be more challenging than the traditional classroom because of the technological constraints, digital divide, insufficient data pack to access the material to attend the class, poor connectivity, lack of device, poor learning environment, technophobia, delayed response and incapability of the teacher to handle efficiently the material and communication machineries.

Due to time restriction and the COVID-19 pandemic, the study was constrained only to Dhaka region in Bangladesh.

The outcomes of the work can be supportive to the governing bodies and proprietors of the higher schooling organizations who are forecasting to adopt online education as a consistent movement in the future.

At last, based on outcomes, investigators have presented some recommendations that can be taken into consideration at policy level. The study would help universities to comply with the pressing need to impart experiential learning through online education during the COVID-19 pandemic.

The purpose of this paper is to investigate how socioeconomic status and demographic factors were associated with child malnutrition as well as how these factors accounted for socioeconomic inequality of child malnutrition in Bangladesh during 2007-2011.

Data of this study come from two cross-sectional rounds (2007 and 2011) of the Bangladesh Demographic and Health Survey. This paper uses ordinary least square models to estimate the correlates of child malnutrition. The study further uses the concentration curve and the concentration index to estimate socioeconomic inequality of child malnutrition in Bangladesh. Finally, the decomposition method is used to explain socioeconomic inequality of child malnutrition in the study period.

Regression analysis indicates that child’s age, breast feeding, child’s birth order, the number of under-five child in the household, household wealth and parental education were strongly correlated with child malnutrition in Bangladesh. This study finds that absolute level of child malnourishment slightly decreased between 2007 and 2011, but socioeconomic inequality increased during this period. Children from the poorest household endured the burden of malnourishment more than those from the wealthiest households. The level of inequality also increased among the rural children, although it remained stagnant among the urban children. Decomposition analysis highlights that parental education had a significant negative relation with the average level of malnutrition, but its role was primarily centred among children from wealthier households.

An approach linking the ministry of health and education with other ministries may speed up the reduction of inequalities in social determinants of childhood undernourishment. Most importantly, there is a need for comprehensive government policies to reduce growing economic inequality and increase the relative income of the poor in Bangladesh.

This study is the first of its kind to apply the decomposition method to explain the socioeconomic inequality of child malnutrition in Bangladesh. This paper presents an enriched understanding of socioeconomic inequality of child malnutrition in Bangladesh during 2007-2011.

The purpose of this study is to improve the tribological characteristics of cotton-biolubricant by adding nanoparticles at extreme pressure (EP) conditions in comparison with commercial lubricant SAE-40.

This research involved the synthesis of cotton-biolubricant by transesterification process and then the addition of nanoparticles in it to improve anti wear (AW)/EP tribological behavior. SAE-40 was studied as a reference commercial lubricant. AW/EP characteristics of all samples were estimated by the four-ball tribo-tester according to the American Society for Testing and Materials D2783 standard.

The addition of 1-Wt.% TiO₂ and Al₂O₃ with oleic acid surfactant in cotton-biolubricant decreased wear scar diameter effectively and enhanced the lubricity, load-wear-index, weld-load and flash-temperature-parameters. This investigation revealed that cotton-biolubricant with TiO₂ nano-particle additive is more effective and will help in developing new efficient biolubricant to replace petroleum-based lubricants.

Cotton biolubricant with TiO₂ nano-particles appeared as an optimistic solution for the global bio-lubricant market.

No one has not studied the cotton biolubricant with nanoparticles for internal combustion engine applications at high temperature and EP conditions.

The purpose of this paper is to provide a new empirical evidence on the impact of economic globalization on the efficiency of the banking sector. The paper also investigates to what extent the internal (i.e. bank specific characteristics) and external (i.e. macroeconomic conditions) factors influence the efficiency of banks while controlling for the impact of the different dimensions of globalization.

The analysis is confined into two stages. In the first stage, the authors employ the bias-corrected data envelopment analysis method to compute the efficiency of individual banks during the period 1999-2012. The authors then use bootstrap regressions to examine the impact of economic globalization on bank efficiency, while controlling for the potential impacts of contextual variables.

The empirical findings indicate that the impacts of personal contacts, information flows, and cultural proximity seem to work in favor of Malaysian banks’ efficiency. A plausible reason could be due to the fact that capital account liberalization is usually accompanied by liberalization of the financial services sector, resulting in a greater competition and subsequently eroding monopolistic profits. The empirical findings also bring forth the importance of and political globalization in determining the efficiency of banks operating in the Malaysian banking sector.

The present study aims to provide for the first time empirical evidence on the performance of the banking sector and to establish new empirical evidence on the impact of globalization. The empirical evidence on the impact of globalization on the banking sector is completely missing from the literature.

The purpose of this paper is to evaluate the prevalence and antibiograms of bacteria isolated from various fresh fruit juices at a local market in Faisalabad.

Fresh fruit juice samples (n=125) were randomly collected using aseptic technique. Each sample (10 mL) was serially diluted with 90 mL of sterile peptone water, from 1×10⁻¹ to 1×10⁻⁵. Each dilution was then used to inoculate nutrient agar by surface spread plating. Aerobic colony counts (ACCs) were determined by colony counting. The isolates were sub-cultured on blood and MacConkey agar. Preliminary identification was achieved on the basis of colony morphology and culture characteristic, and confirmed by API® 20E, 20NE, and API® Staph testing. Antimicrobial susceptibility testing was carried out using the Kirby-Bauer disk diffusion assay, per CLSI 2015 guidelines.

The mean ACC ranged from 2.0×10⁶ CFU/mL to 4.93×10⁶ CFU/mL, with the highest ACC determined for orange juice. Overall, 153 polymicrobial were identified in 125 samples; 103 of these were Gram-negative rods (GNR) and 28 were Gram-positive cocci (GPC). Escherichia coli (n=38), Klebsiella pneumoniae (n=32) and Pseudomonas aeruginosa (n=24) were the predominant GNR; Staphylococcus aureus (n=28) was the predominant GPC. Antibiogram analysis revealed that all GNR were resistant to ampicillin. However, most E. coli isolates were resistant to ceftazidime (72.4 percent of isolates), and ceftriaxone and cefepime (68.9 percent), while most K. pneumoniae isolates were resistant to cefepime (72 percent) and ceftriaxone (64 percent). All S. aureus isolates were resistant to penicillin, while most (64 percent) were resistant to piperacillin; the most effective drugs against bacteria were vancomycin and imipenem.

The findings suggest that the local government regulatory food and public health authorities should take immediate emergency measures. Appropriate surveillance studies and periodic monitoring of food items should be regularly performed to safeguard public health.

The current study revealed the prevalence of multidrug-resistant bacteria in freshly prepared fruit juices sold by local street vendors.

Bangladesh is one of the most flood-prone countries in the world. A number of research works have identified that the flood scenario will be aggravated with climate change context in Bangladesh. In 2014, Bangladesh had prepared municipal level master plan for 222 municipalities with a view to planned urban development. But climate change-induced flood has not been considered in master plan, which poses a question toward the sustainability of the plan. Ullapara Municipality of Sirajganj district has been selected to conduct the research. This study aims to evaluate how infrastructure in proposed master plan will be exposed to climate change-induced flood.

The methodology of this study follows geographic information system (GIS)-based flood exposure analysis of selected infrastructure. These infrastructures include transport infrastructure, educational infrastructure, health infrastructure and other urban facilities. Climate change-induced flood for the year 2040 has been used for flood exposure analysis.

It is evident from the flood exposure analysis that about 33.99% roads will be exposed to 1.5 m–2 m inundation level; seven primary school, six secondary school and four colleges would be highly exposed to 2.0 m–2.50 m inundation level; four health facilities would be exposed to 1.0 m–2.0 m inundation level because of future climate change. This inundation scenario for long duration will lead to dysfunction of concerned infrastructure and, in turn, undermine the stability of a socioeconomic system of Ullapara Municipality.

As the master plan is not fully implemented till now, there is scope for intervention for considering climate change-induced flood to make the plan sustainable.

This study aims to analyse three main questions within the Malaysian banking system: Are Islamic banks more competitive than conventional banks? What are the levels of competition for Islamic and conventional banking sectors pre, during and post the 2007-2009 global financial crisis? Does penetration of Islamic banks affect the competitive structure of conventional banks?

In measuring a bank competition, the author estimates the Panzar–Rosse H-statistic (PRH) method on 17 Islamic and 21 conventional banks in Malaysia over the period of 2004-2013. This is then followed by ordinary least squares (OLS) robust regression analysis to control Islamic banks’ penetration, bank-specific and macroeconomic factors.

Results from the PRH method (total revenue) suggest that Malaysian Islamic banks are relatively more competitive than their conventional counterparts. Furthermore, the author observes that the level of competition for both Malaysian Islamic and conventional banks increased tremendously during the 2007-2009 global financial crisis. This suggests the impact of the crisis on the level of competition for both banking systems. Finally, the OLS robust regression suggests that Islamic banks’ penetration has a significantly positive impact on the level of competition for conventional banks. The PRH estimation using total interest income indicates similar results, suggesting the robustness of these results.

This study reveals whether Islamic banks’ penetration is able to increase the level of competition within the conventional banking sector. Knowledge on this is important to the policymaker.

To the best of the author’s knowledge, this is the first study using the PRH method in comparing the level of competition for Malaysian Islamic and conventional banks. Furthermore, this is the first study analysing the impact of Malaysian Islamic banks’ penetration on the level of competition for conventional banks.

Globalisation has influenced many countries, over the last few decades with financial globalisation and liberalisation bringing regulatory reforms in the banking sector. Thus, this study aims to fill a gap in the literature by examining the influence of globalisation on Islamic and conventional bank productivity in Southeast Asia.

The sample comprised 155 banks (23 Islamic and 132 conventional) from 4 countries from 2008 to 2017. Panel data techniques will be used, together with data envelopment analysis (DEA)-based Malmquist productivity index (MPI), to investigate the impact of chosen main determinants on bank productivity. A panel regression analysis will be performed after generating the productivity index from the DEA-based MPI frontier.

According to the findings, Islamic banks are statistically significantly more productive than conventional banks, and the findings of the t-test are corroborated by the findings of nonparametric tests. Furthermore, the findings of the panel regression model reveal that bank specific factors and macroeconomic variables are significant determinants to bank productivity. Surprisingly, the findings also show that the influence of social globalisation elements tends to be negatively related to conventional bank productivity.

This study adds to the existing literature by bridging the globalisation gap in the productivity of the dual banking industry, particularly in the specific context of Southeast Asia, given that the area is representative of Islamic and finance globally.