19672 research outputs found
Sort by
Renewable Energy for Sustainable Growth and Development: An Evaluation of Law and Policy of Bangladesh
No full textBangladesh's constant growth with an annual 6% plus Gross Domestic Product (GDP) for more than the last two decades and achievements in other socio-economic metrics in recent times is impressive and recognized by various global authoritative bodies. The extent of overwhelming economic ventures in the private sector coupled with the commitments of the government clearly demonstrates the transformation of the country from a primarily agro-based economy to one influenced by the manufacturing and service sectors. Bangladesh is fortunate to have fossil fuel reserves on a limited scale, though these are not enough to run the ongoing massive scale development activities, both in private and public sectors. Thus, the constant and uninterrupted supply of energy at an affordable price remains a serious concern for the successive governments. Therefore, this issue of supply of constant energy has turned to be an important part in the national development agenda. Besides, the country is one of the worst victim nations of the devastating effects of global warming and climate change. As Bangladesh is geographically located in a favorable place in the world map with the availability of plenty of renewable energy sources (RES), the policymakers started to take initiatives leading to exploiting these sources to meet the energy demand of the country. There are both prospects and administrative, legal, technological, socio-cultural and environmental challenges. To address these challenges, it requires comprehensive policy initiatives. A good number of technical and scientific research containing findings and recommendations are available. This paper, which is based on adopting a qualitative research methodology where the contents of secondary sources were analyzed, is an initial attempt to highlight the renewable energy developments in Bangladesh, and subsequently, to evaluate the relevant legal and policy initiatives in the light of international best practices. We advance several recommendations that the stakeholders can consider exploiting RES effectively to attain inclusive, equitable and sustainable development in Bangladesh. These include, inter alia: (1) Enhancing government participation to lead the development of renewable energy (RE); (2) ensuring localization of RE technology; (3) reducing the expenses of energy generation through RES and providing assistance in initial investments; (4) introducing comprehensive legal and regulatory policy for the development of RE industry in Bangladesh; and (5) conducting effective public awareness. © 2019 by the authors
Radiological risks assessment of building materials ingredients: Palm oil clinker and fuel ash
No full textTechnical benefits relevant to the use of palm oil clinker (POC) and fuel ash (POFA) in building materials has been well documented. However, the radiological health hazards caused by the incorporation of POC and POFA as an ingredient of building materials have not been studied so far. The radioactivity levels were measured by γ-ray spectrometry using hyper-pure germanium (HPGe) detector. The activity concentration of 226 Ra and 232 Th in POC and POFA was found to be in the ranges of 5.56 ± 0.23 to 9.03 ± 0.21 and 4.21 ± 0.03 to 7.98 ± 0.19 Bq kg −1 , respectively, and these values were lower than the world average values of 50 Bq kg −1 for building materials. The 40 K value was within the range of 413.01 ± 1.78 to 604.66 ± 2.18 Bq kg −1 . Several radiological parameters and hazard indices, i.e. radium equivalent activity, absorbed dose rate and annual effective dose etc. were calculated for the evaluation of the potential radiological hazards. The obtained values fall within the recommended limit set by various international organizations. Since the activity levels of 226 Ra, 232 Th and 40 K in POC and POFA were significantly lower than the corresponding literature data for other ingredients of building materials, it indicates that POC and POFA are safe to be used in concrete construction. © The Author(s) 2018
Improving internal-valued inferencing with Likelihod Ratio
No full textThis paper point out the limitations of Interval-Valued Inferencing as a defuzzification method for inference engines based on the Bandler-Kohout subproduct. As an improvement, a measurement on the likelihood of an inference result in an acceptance/rejection band suggested. With this improvement, more meaningful results are generated from a Bandler-Kohout subproduct based inference system, especially if it is implemented as a medical decision support system. To demonstrate the capability of this improvement, an experiment with a popular dataset is carried out. © 2019, Faculty of Computer Science and Information Technology
Magnesium oxide (MgO) thin film as saturable absorber for passively mode locked erbium-doped fiber laser
No full textA passively mode locked erbium-doped fiber laser (EDFL) operating at center wavelength of 1569.1 nm is demonstrated based on magnesium oxide (MgO) thin film as a saturable absorber (SA) for the first time. MgO SA was constructed using casting solvent method, and it found that it exhibits suitable modulation depth of about 32.4% and saturation intensity of 16 MW/cm 2 . Self-started mode locked pulse trains with fix repetition rate of 3.5 MHz, short pulse duration of 5.6 ps and high signal to noise ratio (SNR) of 50 dB were achieved at maximum input pump power of 159 mW. © 201
1,1′-Butylenebis(3-sulfo-3H-imidazol-1-ium) hydrogensulfate: a versatile task-specific ionic liquid catalyst for the synthesis of 4H-pyran scaffolds through non-conventional process
No full textAbstract: In the present study, the catalytic efficiency of 1,1′-butylenebis(3-sulfo-3H-imidazol-1-ium) hydrogensulfate (BBSI-HSO 4 ) as a versatile sulfonic acid-functionalized ionic liquid was demonstrated for the one-pot mechanosynthesis of pyrano[4,3-b]-pyrans using planetary ball mill at room temperature under solvent-free conditions. This efficient mechanosynthesis approach to the 4H-pyran scaffolds displays a combination of the structure–activity relationship of ionic liquids with ecological benefits of a mechanocatalytic procedure. The ionic liquid was easily recycled and reused several times with no significant loss of its catalytic activity. Graphical abstract: [Figure not available: see fulltext.]. © 2019, Springer-Verlag GmbH Austria, part of Springer Nature
Oral toxicity of arjunolic acid on hematological, biochemical and histopathological investigations in female Sprague Dawley rats
No full textBackground: Arjunolic acid (AA) is a potent phytochemical with wider pharmacological activities. Despite potential medicinal properties on various in vitro and in vivo studies, there is still a dearth of scientific data related to its safety profile and toxicological parameters. The current study aimed to investigate acute toxicity of AA in normal female Sprague Dawley rats. Methods: In this study, AA was administered orally at an individual dose of 300 and 2000 mg/kg body weight to group 1 and 2 respectively, while group 3 served as normal control. All the animals were observed for 2 weeks to determine any behavioral and physical changes. On day 15, blood was collected for hematological and biochemical investigation, later animals from all the three groups were euthanized to harvest and store essential organs for histopathological analysis. Four different staining techniques; hematoxylin and eosin, Masson trichrome, Periodic acid Schiff and Oil O Red were used to investigate any alterations in different tissues through microscopical observation. Results: The results of the study showed no morbidity and mortality at two different dosage of AA treatment. Daily food &water intake, body weight, relative organ weight, hematological and biochemical parameters were detected to be normal with no severe alteration seen through microscopical investigation in the structure of harvested tissues. Our findings support the safety profile of AA, which was well tolerated at higher dose. Thus, an in-detail study on the subacute disease model is warranted. © 2019 Aamir et al
Evaluation of thermal and solar performance in atrium buildings using sequential simulation
No full textNowadays complex atrium design is becoming popular in city skylines that bring natural lighting to create more pleasant indoor environment. Atriums with complex skylight design and lack of knowledge in building thermal performance in relation to transmitted solar radiation through skylight contribute to greenhouse effect. This has imposed high-energy consumption for cooling load particularly in warm humid regions. In order to obtain good thermal performance of atrium with appropriate skylight design, scholars in atrium studies have suggested that designers should test, simulate and evaluate the thermal performance of atrium building at the early design stage. This paper aims to investigate thermal and solar performance of atrium skylight design in warm humid region. Three thermal analysis software with different capabilities in evaluating thermal and solar performance of skylight forms, positioning and orientation were utilized. Five types of atrium design were modelled and simulated using Ecotect, EnergyPlus and solar radiation simulation model. The results have revealed that different software has different capabilities in measuring thermal and solar performance in atrium skylight design. Each software was used sequentially to provide results in stages starting from verifying variables, identifying critical climatic regions, measuring initial and validating accurate energy use for heating and cooling load until amount of solar received on atrium roof surface, geometry and curvature been achieved. This research could guide designers and engineers to understand the capabilities and reliability of selected thermal and solar analysis software in simulating and evaluating atrium’s thermal and solar performance at early stage design in order to identify appropriate low energy atrium design. © The Author(s) 2019
Theologising the Discourse of Representation through ‘Faith’ and Religion in Football News
No full textThe paper examines the use of ‘faith’ in football through the analysis of the patterns of its co-occurrences in the corpus of football news articles in The Star, a local Malaysian English language newspaper. These articles have been produced by the local news authors who claim to be the faithful of particular football teams. The use of ‘faith’ has been found to express and call for the allegiance towards the preferred teams which is addressed to the audience in general. In this sense, the overdetermined role of the authors as the news producers and the supporters of certain football teams may contribute to how they are represented in the media. Moreover, ‘faith’ has often been limited to religion and little is known about its use in sport and representation. Hencethe investigation is aimed at making sense of the meanings of ‘faith’ in the context of football to further unveil its role in the discourse of representation. The results reveal the co-occurrences of ‘faith’ with the vocabulary of religion simulating interdiscursive relations that strategise on theologising the representation of the news participants in attempts to legitimise the allegiance to particular sides in football naturally. Consequently, using faith of religion to call for faith in football may lead to the glorification and derogation of certain football teams that further influence their representation as ‘Us’ or ‘Them’. As this practice may also be accepted as a common practice indicating sports rivalry, it also makes ‘faith’ a naturalised code without appearing to be ideological. © 2019 Penerbit Universiti Kebangsaan Malaysia. All rights reserved
Urine NMR Metabolomic Study on Biochemical Activities to Investigate the Effect of P. betle Extract on Obese Rats
No full textThe present studies are to evaluate the ability of PB to induce weight loss and urine metabolite profile of Piper betle L. (PB) leaf extracts using metabolomics approach. Dried PB leaves were extracted with ethanol 70% and the studies were performed in different groups of rats fed with high fat (HFD) and normal diet (ND). Then, fed with the PB extract with 100, 300, and 500 mg/kg and two negative control groups given water (WTR). The body weights were monitored and evaluated. Urine was collected and 1H NMR-based metabolomics approach was used to detect the metabolite changes. Results showed that PB-treated group demonstrated inhibition of body weight gain. The trajectory of urine metabolites showed that PB-treated group gave the different distribution from week 12 to 16 compared with the control groups. In 1H NMR metabolomic approach analysis, the urine metabolites gave the best separation in principle component 1 and 3, with 40.0% and 9.56% of the total variation. Shared and unique structures (SUS) plot model showed that higher concentration PB-treated group was characterized by high level of indole-3-acetate, aspartate, methanol, histidine, and creatine, thus caused an increased the metabolic function and maintaining the body weight of the animals treated. © 2019, Springer Science+Business Media, LLC, part of Springer Nature
Optimizing Treatment of Oil Palm-Empty Fruit Bunch (OP-EFB) Fiber: Chemical, Thermal and Physical Properties of Alkalized Fibers
No full textOil-palm empty fruit bunch (EFB) is a waste matter that is abundantly generated from the oil palm industries. Natural fibers derived from this lignocellulosic biomass have the potential to be used as reinforcement material in polymer composites as a greener alternative to synthetic fibers. However, some treatment has to be done to overcome inherent disadvantages in natural fibers and further improve its properties. One such method to prepare the fibers for chemical modification is by alkalization. In this study the EFB fibers were immersed in sodium hydroxide (NaOH) solution with concentrations and immersion times varied to 4, 8 and 12 w/v % and 6, 12, 24 and 48 h, respectively. The EFB fibers were characterized using FTIR, TGA, XRD, FE-SEM, diameter profiling and mechanical tests. Results from FTIR showed that the treated EFB have significant increment of intensity at 3335 cm-1 corresponding to -OH groups. Optimum treatment conditions for the EFB fibers were found at 4 w/v% NaOH and 24 h. Diameter profiling showed better uniformity in the treated EFB fibers with improved tensile properties. © 2019, The Korean Fiber Society