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991.
Shyfuddin Ahmed Boubakari Ibrahimou Shirmin Bintay Kader Muhammad Ashique Haider Chowdhury Habibul Ahsan Mohammad Yunus 《Indoor air》2021,31(6):2167-2175
Despite significant investment, childhood malnutrition continues to be a significant public health problem especially in least developed countries. The aim of this study was to find association between household biomass fuel (BMF) use and childhood malnutrition in Bangladesh using data from Demographic and Health Survey 2011. We included a total 6891 children under 5 years of age in the analysis. The prevalence of wasting, underweight, and stunting from BMF using household was 16.1% (n = 997; 95%CI, 15.1–17.3), 39.0% (n = 2399; 95%CI, 37.1–40.9), and 43.3% (n = 2620; 95%CI, 41.6–45.1), respectively. Underweight and stunting were significantly higher among children from households using BMF compared with the children from CF using households (underweight, biomass vs clean fuel: 39.0% vs. 23.5%, p < 0.001; stunting, biomass vs clean fuel: 43.3 vs. 31.5%, p < 0.001). The use of BMF in the household was significantly associated with underweight (OR = 1.38; 95%CI: 1.10–1.73) and stunting (OR = 1.58; 95%CI: 1.18–1.98) among children <5 years of age after adjusting possible confounders in mixed effect logistic regression analysis. This study found a significant association between chronic childhood malnutrition and household BMF use which is indicating possible alternative risk factor for malnutrition. Further prospective research is required to explore the mechanism of how BMF use results in chronic malnutrition. 相似文献
992.
Javaid Akhtar Muhammad Imran Yaqub Javed Iqbal Naseer Sheikh Tanzila Saba 《国际自然能源杂志》2018,39(8):904-908
In this review the energy potential of Pakistan from hydro, coal, wind, solar and nuclear sources has been discussed. The new projects that are being commissioned on coal, wind, solar, hydel and nuclear-based technologies have also been mentioned. The review has also explored the future prospects of the country’s energy requirements. Pakistan has potential to produce 100,000?MW of electricity from Thar coal for 20 years, 56,000?MW of hydroelectricity, 150,000?MW of wind energy and ~50,000?MW from solar sources. The coal-fired power generation is expected to 11,500?MW in period 2017–2019. The country is moving in the right direction to cater its energy needs. However, there is a need to find local and foreign investment in the country to meet high energy demands in the country in future. 相似文献
993.
International Journal of Steel Structures - Stiffened plates with high slenderness parameters show large out-of-plane deflections, due to elastic buckling, which may occur before the plates reach... 相似文献
994.
Muhammad Shafqat Ali Muhammad Sagheer Aslam M. Saeed Mirza 《Structure and Infrastructure Engineering》2016,12(11):1381-1394
This paper deals with the development of a framework for assessment of sustainability of bridges, including related technical, economic, environmental and social issues. Sustainable infrastructure assets require diligent conception and design of facilities (with diligent choice of materials and construction techniques), high quality construction, and operations, involving routine maintenance, with optimised life-cycle performance and costs, and minimum impact on the environment over a stipulated long service life and beyond. Partial details of design, construction, maintenance and rehabilitation/renovation of the four versions of the 3-km long Victoria Bridge (1859, 1898, 1958 and 1988) are summarised, along with the partial details of design, construction, severe deterioration and subsequent rehabilitation of the nearly 6-km long, 6-lane Champlain Bridge. Sustainability of both bridges was assessed by implementing the proposed sustainability framework developed in this research programme, along with the use of the analytical hierarchy process which involved evaluation of pairwise comparison of the various categories to assist with evaluation of the sustainability scores. These scores indicate that all four forms of Victoria Bridge (1859, 1898, 1958 and 1988) are partially sustainable, or sustainable, while the Champlain Bridge is unsustainable. This framework can be appropriately adapted for assessing the sustainability of other infrastructure assets. 相似文献
995.
为了深入研究中巴喀喇昆仑公路洪扎河以北地段的顺层岩质边坡弯曲失稳机制,采用材料力学压杆稳定及刚性体平衡原理,在D.S.Cavers的基础上考虑地震力作用,分析得到岩质边坡的三种弯曲模型(平面边坡的柔性弯曲、平面边坡的三铰梁模型、曲线边坡的三绞铰模型)的失稳公式,将地震与非地震作用下平面边坡的柔性弯曲进行对比分析。研究结果表明:当内摩擦角φj处于0°~15°范围时,若水平地震加速度方向与岩体弯曲方向相反,平面边坡柔性弯曲模型在地震作用下不易发生弯曲变形;若水平地震加速度方向与岩体弯曲方向一致,地震作用下平面边坡柔性弯曲模型的临界状态总长度l总比非地震作用下的l小,平面边坡在此方向的地震作用下更易发生柔性弯曲变形。 相似文献
996.
Nain Tara Mazhar Iqbal Qaisar Mahmood Khan Muhammad Afzal 《Water and Environment Journal》2019,33(1):124-134
This pilot study evaluated the effects of bacterial augmentation on the efficiency of floating treatment wetlands (FTWs) to remediate textile wastewater. Two wetland plants, Phragmites australis and Typha domingensis, were used to develop FTWs, which were then augmented with a bacterial consortium of three strains (Acinetobacter junii, Pseudomonas indoloxydans, and Rhodococcus sp.). Results showed that both plant species removed colour, organic matter, toxicity, and heavy metals from textile wastewater and their removal efficiency was further enhanced by augmentation with bacteria. The maximum removal efficiencies of colour, COD and BOD after an 8‐day period were 97, 87 and 92%, respectively, by FTWs carrying P. australis inoculated with the bacterial consortium. Furthermore, the same combination showed 87–99% reduction of heavy metals in the textile wastewater as well. These results indicate that FTWs can be used for the treatment of textile effluent and their working efficiency can be improved by plant‐bacterial synergism. 相似文献
997.
Izhar AHMAD Kashif Ali KHAN Tahir AHMAD Muhammad ALAM Muhammad Tariq BASHIR 《Frontiers of Structural and Civil Engineering》2022,16(5):589
In recent building practice, rapid construction is one of the principal requisites. Furthermore, in designing concrete structures, compressive strength is the most significant of all parameters. While 3-d and 7-d compressive strength reflects the strengths at early phases, the ultimate strength is paramount. An effort has been made in this study to develop mathematical models for predicting compressive strength of concrete incorporating ethylene vinyl acetate (EVA) at the later phases. Kolmogorov-Smirnov (KS) goodness-of-fit test was used to examine distribution of the data. The compressive strength of EVA-modified concrete was studied by incorporating various concentrations of EVA as an admixture and by testing at ages of 28, 56, 90, 120, 210, and 365 d. An accelerated compressive strength at 3.5 hours was considered as a reference strength on the basis of which all the specified strengths were predicted by means of linear regression fit. Based on the results of KS goodness-of-fit test, it was concluded that KS test statistics value (D) in each case was lower than the critical value 0.521 for a significance level of 0.05, which demonstrated that the data was normally distributed. Based on the results of compressive strength test, it was concluded that the strength of EVA-modified specimens increased at all ages and the optimum dosage of EVA was achieved at 16% concentration. Furthermore, it was concluded that predicted compressive strength values lies within a 6% difference from the actual strength values for all the mixes, which indicates the practicability of the regression equations. This research work may help in understanding the role of EVA as a viable material in polymer-based cement composites. 相似文献
998.
Based on the equilibrium configuration paths, this study investigates the postbuckling behaviour, including the shape recovery capability, of stainless steel (SUS304) columns after a complete loading-unloading cycle. Experiments were conducted and later numerical simulation was carried out in order to analyze the observed buckling and postbuckling behaviour. Large deflection analysis is necessary for slender columns. Moreover, comparison of the experimental critical load with analytical predictions verifies the fact that physical nonlinearity should be taken into account to analyze the column’s buckling behaviour comprehensively. Thus, based on large deflection theory as well as the nonlinear stress-strain relations, the load-deformation curves of the columns during a complete loading-unloading cycle have been predicted by using the finite element modelling (FEM) code ANSYS.Precise and quantitative analyses of the results verify the fact that the material’s stress-strain properties, both in tension and compression, attribute to the column’s buckling behaviour. 相似文献
999.
Kai Xiang Koh Dong Wang Muhammad Shazzad Hossain 《Bulletin of Engineering Geology and the Environment》2018,77(3):953-962
Caissons are widely used to support fixed platforms in shallow water or moor floating platforms in deep water. Although the installation and pullout behaviours of caissons have been explored extensively, few studies are on the dissipation of excess pore pressures induced by installation of the caisson. The pull-out capacity or bearing capacity of the caisson under undrained conditions is enhanced by dissipation of excess pore pressure, given the caisson is installed in normally consolidated cohesive soil. This paper reports numerical simulations of caisson installation and the subsequent dissipation. The analyses were carried out using a coupled effective stress-pore pressure large deformation finite element (LDFE) approach incorporating the modified Cam-Clay model. The robustness of the LDFE model was validated by comparing the penetration resistance with centrifuge testing data and the guidelines. Caissons in two fine grained soils, kaolin clay and calcareous silt, were explored. The geometry of the caisson was varied to encompass the typical sizes of caissons. The dissipation responses at four locations near the caisson tip were interpreted. A normalised dissipation time around caissons is proposed, by modifying the conventional expression for a cone. 相似文献
1000.