Search results for: Ahsan Nazir

Authors: Joel Y. Y. Loh, Geoffrey A. Ozin, Charles A. Mims, Nazir P. Kherani

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A major goal in the emerging field of solar fuels is to realize an ‘artificial leaf’ – a material that converts light energy in the form of solar photons into chemical energy – using CO2 as a feedstock to generate useful chemical species. Enabling this technology will allow the greenhouse gas, CO2, emitted from energy and manufacturing production exhaust streams to be converted into valuable solar fuels or chemical products. Indium Oxide (In2O3) with surface hydroxyl (OH) groups have been shown to reduce CO2 in the presence of H2 to CO with a reaction rate of 15 μmol gcat−1 h−1. The likely mechanism is via a Frustrated Lewis Pair sites heterolytically splitting H2 to be absorbed and form protonic and hydric sites that can dissociate CO2. In this study, we investigate the dependence of oxygen composition of In2O3 on the CO2 reduction rate. In2O3-x films on quartz fiber paper were DC sputtered with an Indium target and varying O2/Ar plasma mixture. OH surface groups were then introduced by immersing the In2O3-x samples in KOH. We show that hydroxylated In2O3-x reduces more CO2 than non-hydroxylated groups and that a hydroxylated and higher O2/Ar ratio sputtered In2O3-x has a higher reaction rate of 45 μmol gcat-1 h-1. We show by electrical resistivity-temperature curves that H2 is adsorbed onto the surface of In2O3 whereas CO2 itself does not affect the indium oxide surface. We also present activation and ionization energy levels of the hydroxylated In2O3-x under vacuum, CO2 and H2 atmosphere conditions.

Keywords: solar fuels, photocatalysis, indium oxide nanoparticles, carbon dioxide

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Authors: Tanveer Iqbal, Saima Yasin, Muhammad Zafar, Ahmad Shakeel, Fahad Nazir, Paul F. Luckham

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The contact performance of polymeric composites is dependent on the localized mechanical properties of materials. This is particularly important for fiber oriented polymeric materials where self-lubrication from top layers has been the basic requirement. The nanoindentation response of fiber reinforced poly(etheretherketone), PEEK, composites have been evaluated to determine the near-surface mechanical characteristics. Load-displacement compliance, hardness and elastic modulus data based on contact compliance mode (CSM) indentation of carbon fiber oriented and glass fiber oriented PEEK composites are reported as a function of indentation contact displacement. The composite surfaces were indented to a maximum penetration depth of 5µm using Berkovich tip indenter. A typical multiphase response of the composite surface is depicted from analysis of the indentation data for the composites, showing presence of polymer matrix, fibers, and interphase regions. The observed experimental results show that although the surface mechanical properties of carbon fiber based PEEK composite were comparatively higher, the properties of matrix material were seen to be increased in the presence of glass fibers. The experimental methodology may provide a convenient means to understand morphological description of the multimodal polymeric composites.

Keywords: nanoindentation, PEEK, modulus, hardness, plasticization

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Authors: Sajeeha Ansar, Asad Ali Safi, Sheikh Ziauddin, Ahmad R. Shahid, Faraz Ahsan

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Gliomas are most challenging and aggressive type of tumors which appear in different sizes, locations, and scattered boundaries. CNN is most efficient deep learning approach with outstanding capability of solving image analysis problems. A fully automatic deep learning based 2D-CNN model for brain tumor segmentation is presented in this paper. We used small convolution filters (3 x 3) to make architecture deeper. We increased convolutional layers for efficient learning of complex features from large dataset. We achieved better results by pushing convolutional layers up to 16 layers for HGG model. We achieved reliable and accurate results through fine-tuning among dataset and hyper-parameters. Pre-processing of this model includes generation of brain pipeline, intensity normalization, bias correction and data augmentation. We used the BRATS-2015, and Dice Similarity Coefficient (DSC) is used as performance measure for the evaluation of the proposed method. Our method achieved DSC score of 0.81 for complete, 0.79 for core, 0.80 for enhanced tumor regions. However, these results are comparable with methods already implemented 2D CNN architecture.

Keywords: brain tumor segmentation, convolutional neural networks, deep learning, HGG

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Authors: Fatema-Tuz-Zahura, Raquib Ahsan

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Punching shear failure is usually the governing failure mode of flat plate structures. Punching failure is brittle in nature which induces more vulnerability to this type of structure. In the present study, a 3D finite element model of a flat plate with low reinforcement ratio and without any transverse reinforcement has been developed. Punching shear stress and the deflection data were obtained on the surface of the flat plate as well as through the thickness of the model from numerical simulations. The obtained data were compared with the experimental results. Variation of punching stress with respect to deflection as obtained from numerical results is found to be in good agreement with the experimental results; the range of variation of punching stress is within 5%. The numerical simulation shows an early and gradual onset of nonlinearity, whereas the same is late and abrupt as observed in the experimental results. The range of variation of punching stress for different slab thicknesses between experimental and numerical results is less than 15%. The developed numerical model is useful to complement available punching test series performed in the past. The results obtained from the numerical model will be helpful for designing retrofitting schemes of flat plates.

Keywords: flat plate, finite element model, punching shear, reinforcement ratio

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Authors: Mariyam Arif, Ye Liu, Israr Ul Haq, Ahsan Ashfaq

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High cost of fossil fuels and intensifying installations of alternate energy generation sources are intimidating main challenges in power systems. Making accurate load forecasting an important and challenging task for optimal energy planning and management at both distribution and generation side. There are many techniques to forecast load but each technique comes with its own limitation and requires data to accurately predict the forecast load. Artificial Neural Network (ANN) is one such technique to efficiently forecast the load. Comparison between two different ranges of input datasets has been applied to dynamic ANN technique using MATLAB Neural Network Toolbox. It has been observed that selection of input data on training of a network has significant effects on forecasted results. Day-wise input data forecasted the load accurately as compared to year-wise input data. The forecasted load is then distributed among the six generators by using the linear programming to get the optimal point of generation. The algorithm is then verified by comparing the results of each generator with their respective generation limits.

Keywords: artificial neural networks, demand-side management, economic dispatch, linear programming, power generation dispatch

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Authors: Mohd Bahroddin Badri, Ridzuan Masri

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Despite the existence of large volume of waqf assets, it is argued that the potential of these assets not fully unleashed. There are many waqf assets especially in the form of land waqf that are idle and undeveloped mainly because of the insufficient fund and lack of investment expertise. This paper attempts to explore few cases on the innovation of waqf development in Malaysia and some countries that demonstrate synergistic collaboration between stakeholders, e.g., the government, nazir, Islamic religious councils, corporate entities and Islamic financial institutions for waqf development. This paper shows that cash waqf, corporate waqf, Build-Operate-Transfer (BOT) and Sukuk are found to be contemporary mechanisms within Islamic finance ecosystem that drive and rejuvenate the development of waqf to the next level. It further highlights few samples of waqf Sukuk that were successfully issued in selected countries. This paper also demonstrates that the benefit of waqf is beyond religious matters, which may also include education, healthcare, social care, infrastructure and corporate social responsibility (CSR) activities. This research is qualitative in nature, whereby the researcher employs descriptive method on the collected data. The researcher applies case study and library research method to collect and analyse data from journal articles, research papers, conference paper and annual reports. In a nutshell, the potential of contemporary models as demonstrated in this paper is very promising, in which the practical application of those instruments should be expanded for the rejuvenation of waqf asset.

Keywords: cash waqf, corporate waqf, Sukuk waqf, build-operate-transfer

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Authors: Asadullah I. Qazi, Mansoor Ahsan, Zahir Ashraf, Uzair Ahmad

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System identification of an Unmanned Aerial Vehicle (UAV), to acquire its mathematical model, is a significant step in the process of aircraft flight automation. The need for reliable mathematical model is an established requirement for autopilot design, flight simulator development, aircraft performance appraisal, analysis of aircraft modifications, preflight testing of prototype aircraft and investigation of fatigue life and stress distribution etc.  This research is aimed at system identification of a fixed wing UAV by means of specifically designed flight experiment. The purposely designed flight maneuvers were performed on the UAV and aircraft states were recorded during these flights. Acquired data were preprocessed for noise filtering and bias removal followed by parameter estimation of longitudinal dynamics transfer functions using MATLAB system identification toolbox. Black box identification based transfer function models, in response to elevator and throttle inputs, were estimated using least square error   technique. The identification results show a high confidence level and goodness of fit between the estimated model and actual aircraft response.

Keywords: fixed wing UAV, system identification, black box modeling, longitudinal dynamics, least square error

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Authors: Ahsan Abdullah, Ahmed A. S. Bakshwain

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Livestock is one of the fastest-growing sectors in agriculture. If carefully managed, have potential opportunities for economic growth, food sovereignty and food security. In this study we mainly analyse and compare long-term i.e. for year 2030 climate variability impact on predicted productivity of meat i.e. beef, mutton and poultry for the Kingdom of Saudi Arabia w.r.t three factors i.e. i) climatic-change vulnerability ii) CO2 fertilization and iii) water scarcity and compare the results with two countries of the region i.e. Iraq and Yemen. We do the analysis using data from diverse sources, which was extracted, transformed and integrated before usage. The collective impact of the three factors had an overall negative effect on the production of meat for all the three countries, with adverse impact on Iraq. High similarity was found between CO2 fertilization (effecting animal fodder) and water scarcity i.e. higher than that between production of beef and mutton for the three countries considered. Overall, the three factors do not seem to be favorable for the three Middle-East countries considered. This points to possibility of a vegetarian year 2030 based on dependency on indigenous live-stock population.

Keywords: prediction, animal-source foods, pastures, CO2 fertilization, climatic-change vulnerability, water scarcity

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Authors: Ahsan Ahmed, Ming Lu, Syed Zaidi, Farhan Khan

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The Integrated Project Delivery (IPD) method has been proposed as the solution to tackle complexity and fragmentation in the real world while addressing the construction industry’s growing needs for productivity and sustainability. Although the private sector has taken the initiative in implementing IPD and taken advantage of new technology such as building information modeling (BIM) in delivering projects, IPD remains less known and rarely used in public sector construction. The focus of this paper is set on the use of IPD in projects in public sector, which is potentially complemented by the use of analytical functionalities for workface planning and construction oriented design enabled by recent research advances in BIM. Experiences and lessons learned from implementing IPD in the private sector and in BIM-based construction automation research would play a vital role in reducing barriers and eliminating issues in connection with project delivery in the public sector. The paper elaborates issues challenges, contractual relationships and the interactions throughout the planning, design and construction phases in the context of implementing IPD on construction projects in the public sector. A slab construction case is used as a ‘sandbox’ model to elaborate (1) the ideal way of communication, integration, and collaboration among all the parties involved in project delivery in planning and (2) the execution of projects by using IDP principles and optimization, simulation analyses.

Keywords: integrated project delivery, IPD, building information modeling, BIM

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Authors: Awais Ahmed, Atif Rana, Haseeb Zia, Maham Jahangir, Rashed Nazir, Faisal Dar

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Purpose: Biliary complications represent the most common cause of morbidity in living related liver donor transplantation and detailed preoperative evaluation of biliary anatomic variants is crucial for safe patient selection and improved surgical outcomes. Purpose of this study is to determine the accuracy of preoperative MRCP in predicting biliary variations when compared to intraoperative cholangiography in living related liver donors. Materials and Methods: From 44 potential donors, 40 consecutive living related liver donors (13 females and 28 males) underwent donor hepatectomy at our centre from April 2012 to August 2013. MRCP and IOC of all patients were retrospectively reviewed separately by two radiologists and a transplant surgeon.MRCP was performed on 1.5 Tesla MR magnets using breath-hold heavily T2 weighted radial slab technique. One patient was excluded due to suboptimal MRCP. The accuracy of MRCP for variant biliary anatomy was calculated. Results: MRCP accurately predicted the biliary anatomy in 38 of 39 cases (97 %). Standard biliary anatomy was predicted by MRCP in 25 (64 %) donors (100% sensitivity). Variant biliary anatomy was noted in 14 (36 %) IOCs of which MRCP predicted precise anatomy of 13 variants (93 % sensitivity). The two most common variations were drainage of the RPSD into the LHD (50%) and the triple confluence of the RASD, RPSD and LHD (21%). Conclusion: MRCP is a sensitive imaging tool for precise pre-operative mapping of biliary variations which is critical to surgical decision making in living related liver transplantation.

Keywords: intraoperative cholangiogram, liver transplantation, living related donors, magnetic resonance cholangio-pancreaticogram (MRCP)

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Authors: Anders S. Kristensen, Dewan Ahsan, Saqib Mehmood, Shakeel Ahmed

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Traffic accidents are a result of the convergence of hazards, malfunctioning of vehicles and human negligence that have adverse economic and health impacts and effects. Unfortunately, avoiding them completely is very difficult, but with quick response to rescue and first aid, the mortality rate of inflicted persons can be reduced significantly. Smart and innovative technologies can play a pivotal role to respond faster to traffic crash emergencies comparing conventional means of transportation. For instance, Rescue Emergency Drone (RED) can provide faster and real-time crash site risk assessment to emergency medical services, thereby helping them to quickly and accurately assess a situation, dispatch the right equipment and assist bystanders to treat inflicted person properly. To conduct a research in this regard, the case of a traffic roundabout that is prone to frequent traffic accidents on the outskirts of Esbjerg, a town located on western coast of Denmark is hypothetically considered. Along with manual calculations, Emergency Disaster Management Simulation (EDMSIM) has been used to verify the response time of RED from a fire station of the town to the presumed crash site. The results of the study demonstrate the robustness of RED into emergency services to help save lives. 

Keywords: automated external defibrillator, medical emergency, response time, unmanned aerial system

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Authors: Shofiq Ahmed, Rakibul Hassan, Raquib Ahsan

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Concrete is one of the basic elements of RCC structure and also the most crucial one. In recent years, a lot of researches have been conducted to develop special types of concrete for special purposes. Micro-concrete is one of them which has high compressive strength and is mainly used for retrofitting. Micro-concrete is a cementitious based composition formulated for use in repairs of areas where the concrete is damaged & the area is confined in movement making the placement of conventional concrete difficult. According to recent statistics, a large number of structures in the major cities of Bangladesh are vulnerable to collapse. Retrofitting may thus be required for a sustainable solution, and for this purpose, the utilization of micro-concrete can be considered as the most effective solution. For that reason, the aim of this study was to produce micro-concrete using indigenous materials in low cost. Following this aim, the experimental data were observed for five mix ratios with varied amount of cement, fine aggregate, coarse aggregate, water, and admixture. The investigation criteria were a compressive strength, tensile strength, slump and the cost of different mix ratios. Finally, for a mix ratio of 1:1:1.5, the compressive strength was achieved as 7820 psi indicating highest strength among all the samples with the reasonable tensile strength of 1215 psi. The slump of 6.9 inches was also found for this specimen indicating it’s high flowability and making it’s convenient to use as micro-concrete. Moreover, comparing with the cost of foreign products of micro-concrete, it was observed that foreign products were almost four to five times costlier than this local product.

Keywords: indigenous, micro-concrete, retrofitting, vulnerable

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Authors: Syed Ahsan, Saleh Alshomrani, Ishtiaq Rasool, Ali Hassan

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In this oral presentation, we will provide an overview of the technical and semantic architecture of a desert border security and critical infrastructure protection security system. Modern border security systems are designed to reduce the dependability and intrusion of human operators. To achieve this, different types of sensors are use along with video surveillance technologies. Application of these technologies in a harsh desert environment of Saudi Arabia poses unique challenges. Environmental and geographical factors including high temperatures, desert storms, temperature variations and remoteness adversely affect the reliability of surveillance systems. To successfully implement a reliable, effective system in a harsh desert environment, the following must be achieved: i) Selection of technology including sensors, video cameras, and communication infrastructure that suit desert environments. ii) Reduced power consumption and efficient usage of equipment to increase the battery life of the equipment. iii) A reliable and robust communication network with efficient usage of bandwidth. Also, to reduce the expert bottleneck, an ontology-based intelligent information systems needs to be developed. Domain knowledge unique and peculiar to Saudi Arabia needs to be formalized to develop an expert system that can detect abnormal activities and any intrusion.

Keywords: border security, sensors, abnormal activity detection, ontologies

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Authors: Ahsan R. Khokhar, Fizza Hassan

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Alkali-Silica Reaction (ASR) has been recognized as a potential cause of concrete degradation in the world since the 1940s. In Pakistan, mega hydropower structures like dams, weirs constructed from aggregates extracted from a local riverbed exhibited different levels of alkali-silica reactivity over an extended service period. The concrete expansion potential due to such aggregates has been categorized as slow-reactive. Apart from hydropower structures, ASR existence has been identified in the concrete structural elements of a Textile Mill building which used aggregates extracted from the nearby riverbed. The original structure of the Textile Mill was erected in the 80s with the addition of a textile ‘sizing and wrapping’ hall constructed in the 90s. In the years to follow, intensive spalling was observed in the structural members of the subject hall; enough to threat to the overall stability of the building. Limitations such as incomplete building data posed hurdles during the detailed structural investigation. The paper lists observations made while assessing the extent of damage and its effect on the building hall structure. Core testing and Petrographic tests were carried out as per the ASTM standards for strength degradation analysis followed by the identifying its root cause. Results confirmed significant structural strength reduction because of ASR which necessitated the formulation of an immediate re-strengthening solution. The paper also discusses the possible tracks of rehabilitative measures which are being adapted to stabilize the structure and seize further concrete expansion.

Keywords: Alkali-Silica Reaction (ASR), concrete strength degradation, damage assessment, damage evaluation

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Authors: Dimitra V. Peristeri, Hussameldin M. Nour, Amiya Ahsan, Sameh Abogabal, Krishna K. Singh, Muhammad Shafique Sajid

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Introduction: The use of optimal skin antiseptic agents for the prevention of surgical site infection (SSI) is of critical importance, especially during abdominal surgical procedures. Alcohol-based chlorhexidine gluconate (CHG) and aqueous-based povidone-iodine (PVI) are the two most common skin antiseptics used nowadays. The objective of this article is to evaluate the effectiveness of alcohol-based CHG versus aqueous-based PVI used for skin preparation before abdominal surgery to reduce SSIs. Methods: Standard medical databases such as MEDLINE, Embase, Pubmed, and Cochrane Library were searched to find randomised, controlled trials (RCTs) comparing alcohol-based CHG skin preparation versus aqueous-based PVI in patients undergoing abdominal surgery. The combined outcomes of SSIs were calculated using an odds ratio (OR) with 95% confidence intervals (95% CI). All data were analysed using Review Manager (RevMan) Software 5.4, and the meta-analysis was performed with a random effect model analysis. Results: A total of 11 studies, all RCTs, were included (n= 12072 participants), recruiting adult patients undergoing abdominal surgery. In the random effect model analysis, the use of alcohol-based CHG in patients undergoing abdominal surgery was associated with a reduced risk of SSI compared to aqueous-based PVI (OR: 0.84; 95% CI [0.74, 0.96], z= 2.61, p= 0.009). Conclusion: Alcohol-based CHG may be more effective for preventing the risk of SSI compared to aqueous-based PVI agents in abdominal surgery. The conclusion of this meta-analysis may add a guiding value to reinforce current clinical practice guidelines.

Keywords: skin preparation, surgical site infection, chlorhexidine, skin antiseptics

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Authors: Muhammad Dildar Gogi, Muhammad Arshad, Muhammad Ahsan Khan, M. Sufian, Ahmad Nawaz, Mubashir Iqbal, Muhammad Junaid Nisar, Waleed Afzal Naveed

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Larvae of silkworm (Bombyx mori) exhibit very high mortality when reared on mulberry leaves collected from mulberry orchards which get contaminated with metallic/nonmetallic compounds through either drift-deposition or chemigation. There is need to screen out such metallic compound for their toxicity at their various concentrations. The present study was carried out to assess toxicity of metals in different instars of silkworm. Aqueous solutions of nine heavy-metal based salts were prepared by dissolving 50, 100, 150, 200, 250, 300, 350 and 400 mg of each salt in one liter of water and were applied on the mulberry leaves by leaf-dip methods. The results reveal that mortality in 1st, 2nd, 3rd, 4th and 5th instar larvae caused by each heavy metal salts increased with an increase in their concentrations. The 1st instar larvae were found more susceptible to metal salts followed by 2nd, 3rd, 4th and 5th instar larvae of silkworm. Overall, Nickel chloride proved more toxic for all larval instar as it demonstrated approximately 40-99% mortality. On the basis of LC2 and larval mortality, the order of toxicity of heavy metals against all five larval instar was Nickel chloride (LC₂ = 1.9-13.9 mg/L; & 15.0±1.2-69.2±1.7% mortality) followed by Chromium nitrate (LC₂ = 3.3-14.8 mg/L; & 13.3±1.4-62.4±2.8% mortality), Cobalt nitrate (LC₂ = 4.3-30.9; &11.4±0.07-54.9±2.0% mortality), Lead acetate (LC₂ =8.8-53.3 mg/L; & 9.5±1.3-46.4±2.9% mortality), Aluminum sulfate (LC₂ = 15.5-76.6 mg/L; & 8.4±0.08-42.1±2.8% mortality), Barium sulfide (LC₂ = 20.9-105.9; & 7.7±1.1-39.2±2.5% mortality), Copper sulfate (LC2 = 28.5-12.4 mg/L; & 7.3±0.06-37.1±2.4% mortality), Manganese chloride (LC₂ = 29.9-136.9 mg/L; & 6.8±0.09-35.3±1.6% mortality) and Zinc nitrate (LC₂ = 36.3-15 mg/L; & 6.2±1.2-32.1±1.9% mortality). Zinc nitrate @ 50 and 100 mg/L, Barium sulfide @ 50 mg/L, Manganese chloride @ 50 and 100 mg/L and Copper sulfate @ 50 mg/L proved safe for 5th instar larvae as these interaction attributed no mortality. All the heavy metal salts at a concentration of 50 mg/L demonstrated less than 10% mortality.

Keywords: heavy-metals, larval-instars, lethal-concentration, mortality, silkworm

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Authors: Tahsin A. H. Nishat, Raquib Ahsan

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Sensitivity analysis of design parameters of the optimization procedure can become a significant factor while designing any structural system. The objectives of the study are to analyze the sensitivity of deck slab thickness parameter obtained from both the conventional and optimum design methodology of pre-stressed post-tensioned I-girder and deck system and to compare the relative significance of slab thickness. For analysis on conventional method, the values of 14 design parameters obtained by the conventional iterative method of design of a real-life I-girder bridge project have been considered. On the other side for analysis on optimization method, cost optimization of this system has been done using global optimization methodology 'Evolutionary Operation (EVOP)'. The problem, by which optimum values of 14 design parameters have been obtained, contains 14 explicit constraints and 46 implicit constraints. For both types of design parameters, sensitivity analysis has been conducted on deck slab thickness parameter which can become too sensitive for the obtained optimum solution. Deviations of slab thickness on both the upper and lower side of its optimum value have been considered reflecting its realistic possible ranges of variations during construction. In this procedure, the remaining parameters have been kept unchanged. For small deviations from the optimum value, compliance with the explicit and implicit constraints has been examined. Variations in the cost have also been estimated. It is obtained that without violating any constraint deck slab thickness obtained by the conventional method can be increased up to 25 mm whereas slab thickness obtained by cost optimization can be increased only up to 0.3 mm. The obtained result suggests that slab thickness becomes less sensitive in case of conventional method of design. Therefore, for realistic design purpose sensitivity should be conducted for any of the design procedure of girder and deck system.

Keywords: sensitivity analysis, optimum design, evolutionary operations, PC I-girder, deck system

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Authors: Shamim Ahsan

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Abstract Global digital advances associated with consumer’s strong inclination for the state of art digital technologies is causing overwhelming social and environmental challenges for global community. During recent years not only economic advances of electronic industries has taken place at steadfast rate, also the generation of e-waste outshined the growth of any other types of wastes. The estimated global e-waste volume is expected to reach 65.4 million tons annually by 2017. Formal recycling practices in developed countries are stemming economic liability, opening paths for illegal trafficking to developing countries. Informal crude management of large volume of e-waste is transforming into an emergent environmental and health challenge in. Contrariwise, in several studies formal and informal recycling of e-waste has also exhibited potentials for economic returns both in developed and developing countries. Some research on China illustrated that from large volume of e-wastes generation there are recycling potential in evolving from ∼16 (10−22) billion US$ in 2010, to an anticipated ∼73.4 (44.5−103.4) billion US$ by 2030. While in another study, researcher found from an economic analysis of 14 common categories of waste electric and electronic equipment (WEEE) the overall worth is calculated as €2.15 billion to European markets, with a potential rise to €3.67 billion as volumes increase. These economic returns and environmental protection approaches are feasible only when sustainable policy options are embraced with stricter regulatory mechanism. This study will critically review current researches to stipulate how global e-waste generation and sustainable e-waste recycling practices demonstrate future economic development potential in terms of both quantity and processing capacity, also triggering complex some environmental challenges.

Keywords: E-Waste, , Generation, , Economic Potential, Recycling

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Authors: Raquib Ahsan, Md. Mahir Asif, Md. Zahidul Alam

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A huge portion of old masonry buildings in Bangladesh are vulnerable to earthquake. In most of the cases these buildings contain unreinforced masonry wall which are most likely to be subjected to earthquake damages. Due to deterioration of mortar joint and aging, shear resistance of these unreinforced masonry walls dwindle. So, retrofitting of these old buildings has become an important issue. Among many researched and experimented techniques, ferrocement retrofitting can be a low cost technique in context of the economic condition of Bangladesh. This study aims at investigating the behavior of ferrocement retrofitted unconfined URM walls under different types of cyclic loading. Four 725 mm × 725 mm masonry wall units were prepared with bricks jointed by stretcher bond with 12.5 mm mortar between two adjacent layers of bricks. To compare the effectiveness of ferrocement retrofitting a particular type wire mesh was used in this experiment which is 20 gauge woven wire mesh with 12.5 mm × 12.5 mm square opening. After retrofitting with ferrocement these wall units were tested by applying cyclic deformation along the diagonals of the specimens. Then a comparative study was performed between the retrofitted specimens and control specimens for both partially reversed cyclic load condition and cyclic compression load condition. The experiment results show that ultimate load carrying capacities of ferrocement retrofitted specimens are 35% and 27% greater than the control specimen under partially reversed cyclic loading and cyclic compression respectively. And before failure the deformations of ferrocement retrofitted specimens are 43% and 33% greater than the control specimen under reversed cyclic loading and cyclic compression respectively. Therefore, the test results show that the ultimate load carrying capacity and ductility of ferrocement retrofitted specimens have improved.

Keywords: cyclic compression, cyclic loading, ferrocement, masonry wall, partially reversed cyclic load, retrofitting

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Authors: Saiada Fuadi Fancy, Fahim Ahmed, Shofiq Ahmed, Raquib Ahsan

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The worldwide use of reinforced concrete construction stems from the wide availability of reinforcing steel as well as concrete ingredients. However, concrete construction requires a certain level of technology, expertise, and workmanship, particularly, in the field during construction. As a supporting technology for a concrete column or wall construction, kicker is cast as part of the slab or foundation to provide a convenient starting point for a wall or column ensuring integrity at this important junction. For that reason, a comprehensive study was carried out here to investigate the behavior of reinforced concrete frame with different kicker parameters. To achieve this objective, six half-scale specimens of portal reinforced concrete frame with kickers and one portal frame without kicker were constructed according to common practice in the industry and subjected to cyclic incremental horizontal loading with sustained gravity load. In this study, the experimental data, obtained in four deflections controlled cycle, were used to evaluate the behavior of kickers. Load-displacement characteristics were obtained; maximum loads and deflections were measured and assessed. Finally, the test results of frames constructed with three different types of kicker thickness were compared with the kickerless frame. Similar crack patterns were observed for all the specimens. From this investigation, specimens with kicker thickness 3″ were shown better results than specimens with kicker thickness 1.5″, which was specified by maximum load, stiffness, initiation of first crack and residual displacement. Despite of better performance, it could not be firmly concluded that 4.5″ kicker thickness is the most appropriate one. Because, during the test of that specimen, separation of dial gauge was needed. Finally, comparing with kickerless specimen, it was observed that performance of kickerless specimen was relatively better than kicker specimens.

Keywords: crack, cyclic, kicker, load-displacement

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Authors: A. C. Dey, H. M. Ahsan

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Heterogeneous traffic composed of both motorized and non-motorized vehicles that are a common feature of urban Bangladeshi roads. Popular non-motorized vehicles include rickshaws, rickshaw-van, and bicycle. These modes performed an important role in moving people and goods in the absence of a dependable mass transport system. However, rickshaws play a major role in meeting the demand for door-to-door public transport services to the city dwellers. But there is no separate lane for non-motorized vehicles in this city. Non-motorized vehicles generally occupy the outermost or curb-side lanes, however, at intersections non-motorized vehicles get mixed with the motorized vehicles. That’s why the conventional models fail to analyze the situation completely. Microscopic traffic simulation software VISSIM 5.3, itself a lane base software but default behavioral parameters [such as driving behavior, lateral distances, overtaking tendency, CCO=0.4m, CC1=1.5s] are modified for calibrating a model to analyze the effects of non-motorized traffic at an intersection (Mirpur-10) in a non-lane based mixed traffic condition. It is seen from field data that NMV occupies an average 20% of the total number of vehicles almost all the link roads. Due to the large share of non-motorized vehicles, capacity significantly drop. After analyzing simulation raw data, significant variation is noticed. Such as the average vehicular speed is reduced by 25% and the number of vehicles decreased by 30% only for the presence of NMV. Also the variation of lateral occupancy and queue delay time increase by 2.37% and 33.75% respectively. Thus results clearly show the negative effects of non-motorized vehicles on capacity at an intersection. So special management technics or restriction of NMV at major intersections may be an effective solution to improve this existing critical condition.

Keywords: lateral occupancy, non lane based intersection, nmv, queue delay time, VISSIM 5.3

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Authors: Ahsan Khan, Nazish Shah, Muhammad Salman

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The present study deals with the toxicological effects of copper, lead and chromium on brain and liver tissues of grass carp (Ctenopharyngodon idella). The average length of experimental fish was 8.5 ± 5.5 cm and weighed 9.5 ± 6.5 g. Grass carp was exposed to lethal concentration (LC₁₅) of copper, lead and chromium for 24, 48, 72 and 96 hours respectively. (LC₁₅) for copper was 1.5, 1.4, 1.2 and 1mgL⁻¹. Similarly, LC₁₅ of lead was 250, 235, 225 and 216mgL⁻¹ while (LC₁₅) for chromium was 25.5, 22.5, 20 and 18mgL⁻¹ respectively. During the time of exposure against various doses of heavy metals the grass carp showed some behavioral changes. In the initial stages of experiment, the rapid movements and gulping of air were observed. Several times the fish tried to jump to scat from the toxic median. In addition, the accumulation of heavy metals in different tissues of grass carp particularly in liver and brain tissues were observed. Lead was highly accumulated in brain tissue after the exposure of fish for 24 and 48 hours, while highly accumulated in liver tissues after the exposure of fish for 72 and 96 hours. Chromium was highly accumulated in the liver tissues after the exposure of fish for 24 hours while its accumulation was found highly in the brain tissues after the exposure of fish for 48, 72 and 96 hours. Similarly, accumulation of copper concentration was found highly in brain tissues after the exposure of 48 and 96 hours while its accumulation was high in liver tissues after the exposure of 24 and 72 hours. Comparatively maximum accumulation of lead was found in brain and liver tissues of grass carp followed by chromium and copper. Furthermore, accumulation of these metals caused many abnormalities like gliosis, destruction of cell, change in cell shape and shrinkage of cells in brain tissue while in liver tissues aggregation in hepatocytes, widen space between cells and also destruction of cell was observed. These experiments and observations can be useful to monitor the aquatic pollution and quality of aquatic environment system.

Keywords: brain, grass carp, liver, lethal concentration, toxicity

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Authors: Venkata Srikanth Meka, Nur Arthirah Binti Ahmad Tarmizi Tan, Muhammad Syahmi Bin Md Nazir, Adinarayana Gorajana, Senthil Rajan Dharmalingam

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Biphasic drug delivery systems are designed to release drug at two different rates, either fast/prolonged or prolonged/fast. A fast/prolonged release system provides a burst drug release at initial stage followed by a slow release over a prolonged period of time and in case of prolonged/fast release system, the release pattern is vice versa. Terminalia catappa gum (TCG) is a natural polymer and was successfully proven as a novel pharmaceutical excipient. The main objective of the present research is to investigate the applicability of natural polymer, Terminalia catappa gum in the design of oral biphasic drug delivery system in the form of mini tablets by using a model drug, buspirone HCl. This investigation aims to produce a biphasic release drug delivery system of buspirone by combining immediate release and prolonged release mini tablets into a capsule. For immediate release mini tablets, a dose of 4.5 mg buspirone was prepared by varying the concentration of superdisintegrant; crospovidone. On the other hand, prolonged release mini tablets were produced by using different concentrations of the natural polymer; TCG with a buspirone dose of 3mg. All mini tablets were characterized for weight variation, hardness, friability, disintegration, content uniformity and dissolution studies. The optimized formulations of immediate and prolonged release mini tablets were finally combined in a capsule and was evaluated for release studies. FTIR and DSC studies were conducted to study the drug-polymer interaction. All formulations of immediate release and prolonged release mini tablets were passed all the in-process quality control tests according to US Pharmacopoeia. The disintegration time of immediate release mini tablets of different formulations was varied from 2-6 min, and maximum drug release was achieved in lesser than 60 min. Whereas prolonged release mini tablets made with TCG have shown good drug retarding properties. Formulations were controlled for about 4-10 hrs with varying concentration of TCG. As the concentration of TCG increased, the drug release retarding property also increased. The optimised mini tablets were packed in capsules and were evaluated for the release mechanism. The capsule dosage form has clearly exhibited the biphasic release of buspirone, indicating that TCG is a suitable natural polymer for this study. FTIR and DSC studies proved that there was no interaction between the drug and polymer. Based on the above positive results, it can be concluded that TCG is a suitable polymer for the biphasic drug delivery systems.

Keywords: Terminalia catappa gum, biphasic release, mini tablets, tablet in capsule, natural polymers

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Authors: Asif Zaman, Moinul Islam Zaber, Amin Ahsan Ali

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In recent years of industrialization, the South Asian countries are being affected by air pollution due to a severe increase in fine particulate matter 2.5 (PM₂.₅). Among them, Bangladesh is one of the most polluting countries. In this paper, statistical analyses were conducted on the time series of PM₂.₅ from various districts in Bangladesh, mostly around Dhaka city. Research has been conducted on the dynamic interactions and relationships between PM₂.₅ concentrations in different zones. The study is conducted toward understanding the characteristics of PM₂.₅, such as spatial-temporal characterization, correlation of other contributors behind air pollution such as human activities, driving factors and environmental casualties. Clustering on the data gave an insight on the districts groups based on their AQI frequency as representative districts. Seasonality analysis on hourly and monthly frequency found higher concentration of fine particles in nighttime and winter season, respectively. Cross correlation analysis discovered a phenomenon of correlations among cities based on time-lagged series of air particle readings and visualization framework is developed for observing interaction in PM₂.₅ concentrations between cities. Significant time-lagged correlations were discovered between the PM₂.₅ time series in different city groups throughout the country by cross correlation analysis. Additionally, seasonal heatmaps depict that the pooled series correlations are less significant in warmer months, and among cities of greater geographic distance as well as time lag magnitude and direction of the best shifted correlated particulate matter time series among districts change seasonally. The geographic map visualization demonstrates spatial behaviour of air pollution among districts around Dhaka city and the significant effect of wind direction as the vital actor on correlated shifted time series. The visualization framework has multipurpose usage from gathering insight of general and seasonal air quality of Bangladesh to determining the pathway of regional transportation of air pollution.

Keywords: air quality, particles, cross correlation, seasonality

Procedia PDF Downloads 86

Authors: Muhammad Dildar Gogi, Muhammad Jalal Arif, Muhammad Junaid Nisar, Mubashir Iqbal, Waleed Afzal Naveed, Muhammad Ahsan Khan, Ahmad Nawaz, Muhammad Sufian, Muhammad Arshad, Amna Jalal

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Fruit flies of Bactrocera genus cause heavy losses in fruits and vegetables globally and insecticide-application for their control creates issues of ecological backlash, environmental pollution, and food safety. There is need to explore alternatives and food-baits application is considered safe for the environment and effective for fruit fly management. Present experiment was carried out to assess the attractancy of five phagostimulant-Mixtures (PHS-Mix) prepared by mixing banana-squash, mulberry, protein-hydrolysate and molasses with some phagostimulant-lure sources including beef extract, fish extract, yeast, starch, rose oil, casein and cedar oil in five different ratios i.e., PHS-Mix-1 (1 part of all ingredients), PHS-Mix-2 (1 part of banana with 0.75 parts of all other ingredients), PHS-Mix-3 (1 part of banana with 0.5 parts of all other ingredients), PHS-Mix-4 (1 part of banana with 0.25 parts of all other ingredients) and PHS-Mix-5 (1 part of banana with 0.125 parts of all other ingredients). These were evaluated in comparison with a standard (GF-120). PHS-Mix-4 demonstrated 40.5±1.3-46.2±1.6% AI for satiated flies (class-II i.e., moderately attractive) and 59.5±2.0-68.6±3.0% AI for starved flies (class-III i.e., highly attractive) for both B. dorsalis and B. zonata in olfactometric study while the same exhibited 51.2±0.53% AI (class-III i.e., highly attractive) for B. zonata and 45.4±0.89% AI (class-II i.e., moderately attractive) for B. dorsalis in field study. PHS-Mix-1 proved non-attractive (class-I) and moderately attractive (class-II) phagostimulant in olfactometer and field studies, respectively. PHS-Mix-2 exhibited moderate attractiveness for starved lots in olfactometer and field-lot in field studies. PHS-Mix-5 proved non-attractive to starved and satiated lots of B. zonata and B. dorsalis females in olfactometer and field studies. Overall PHS-Mix-4 proved better phagostimulant-mixture followed by PHS-Mix-3 which was categorized as class-II (moderately attractive) phagostimulant for starved and satiated lots of female flies of both species in olfactometer and field studies; hence these can be exploited for fruit fly management.

Keywords: attractive index, field conditions, olfactometer, Tephritid flies

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Authors: Ahsan Ali, Mayank Ostwal, Nikhil Agarwal

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Abstract—According to a World Bank report, millions of people across the globe still do not have access to improved water services. With uninterrupted growth of cities and urban inhabitants, there is a mounting need to safeguard the sustainable expansion of cities. Efficient functioning of the urban components and high living standards of the residents are needed to be ensured. The water and sanitation network of an urban development is one of its most essential parts of its critical infrastructure. The growth in urban population is leading towards increased water demand, and thus, the local water resources are severely strained. 'Smart water' is referred to water and waste water infrastructure that is able to manage the limited resources and the energy used to transport it. It enables the sustainable consumption of water resources through co-ordinate water management system, by integrating Information Communication Technology (ICT) solutions, intended at maximizing the socioeconomic benefits without compromising the environmental values. This paper presents a case study from a medium sized city in North-western Pakistan. Currently, water is getting contaminated due to the proximity between water and sewer pipelines in the study area, leading to public health issues. Due to unsafe grey water infiltration, the scarce ground water is also getting polluted. This research takes into account the design of smart urban water network by integrating ICT (Information and Communication Technology) with urban water network. The proximity between the existing water supply network and sewage network is analyzed and a design of new water supply system is proposed. Real time mapping of the existing urban utility networks will be projected with the help of GIS applications. The issue of grey water infiltration is addressed by providing sustainable solutions with the help of locally available materials, keeping in mind the economic condition of the area. To deal with the current growth of urban population, it is vital to develop new water resources. Hence, distinctive and cost effective procedures to harness rain water would be suggested as a part of the research study experiment.

Keywords: GIS, smart water, sustainability, urban water management

Procedia PDF Downloads 179

Authors: Ramin Mehdiabadi, Neda Menbari, Mohammad Nazir Menbari

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As a pressing public health concern, breast cancer stands as the predominant oncological diagnosis and principal cause of cancer-related mortality among women globally, accounting for 11.7% of new cancer incidences and 6.9% of cancer-related deaths. The annual figures indicate that approximately 230,480 women are diagnosed with breast cancer in the United States alone, with 39,520 succumbing to the disease. While developed economies have reported a deceleration in both incidence and mortality rates across various forms of cancer, including breast cancer, emerging and low-income economies manifest a contrary escalation, largely attributable to lifestyle-mediated risk factors such as tobacco usage, physical inactivity, and high caloric intake. Breast cancer is distinctly characterized by molecular heterogeneity, manifesting in specific subtypes delineated by biomarkers—Estrogen Receptors (ER), Progesterone Receptors (PR), and Human Epidermal Growth Factor Receptor 2 (HER2). These subtypes, comprising Luminal A, Luminal B, HER2-enriched, triple-negative/basal-like, and normal-like, necessitate nuanced, subtype-specific therapeutic regimens, thereby challenging the applicability of generalized treatment protocols. Within this molecular complexity, the transcription factor Forkhead Box M1 (FoxM1) has garnered attention as a significant driver of cellular proliferation, tumorigenesis, metastatic progression, and treatment resistance in a spectrum of human malignancies, including breast cancer. Concurrently, microRNAs (miRs), specifically miR-216b-5p, have been identified as post-transcriptional gene expression regulators and potential tumor suppressors. The overarching objective of this academic investigation is to explicate the multifaceted interrelationship between FoxM1 and miR-216b-5p across the disparate molecular subtypes of breast cancer. Employing a methodologically rigorous, interdisciplinary research design that incorporates cutting-edge molecular biology techniques, sophisticated bioinformatics analytics, and exhaustive meta-analyses of extant clinical data, this scholarly endeavor aims to unveil novel biomarker-specific therapeutic pathways. By doing so, this research is positioned to make a seminal contribution to the advancement of personalized, efficacious, and minimally toxic treatment paradigms, thus profoundly impacting the global efforts to ameliorate the burden of breast cancer.

Keywords: breast cancer, fox m1, microRNAs, mir-216b-5p, gene expression

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Authors: Hassan Wajid, Syed T. Ahmed, Syed G. Haider Jr., Razia Latif, Ahsan Ali, Maira Anam

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The phenomenon of Metamorphosis can be associated with any object, organism, or structure gradually and progressively going through the change of systemic or morphological form. This phenomenon can be integrated while teaching drawing to architecture students. In architectural drawings, metamorphosis’s main focus and purpose are not to completely imitate any object. In the process of drawing, the changes in systemic or morphological form happen until the complete process, and the visuals of the complete process change the drawing, opening up possibilities for the imagination of the perceivers. Metamorphosis in architectural drawings begins with an initial form and, through various noticeable stages, ends up final form or manifestation. How much of the initial form is manifested in the final form and progressively among various intermediate stages becomes an indication of the nature of metamorphosis as a phenomenon. It is important at this stage to clarify that the term metamorphosis is presently being coopted from its original domain, usually in life sciences. In this current exercise, the architectural drawings are to act as an operative analog process transforming one image of art and/or architecture in its broadest sense. That composition is claimed to have come from one source (individual work, a cultural artifact, civilizational remain). It dialectically meets, opposes, or confronts some carefully chosen alien opposites from a different domain. As an example, the layers of a detailed drawing of a Turkish prayer rug of 5 x 7 ratio over a detailed architectural plan of a religious, historical complex can be observed such that the two drawings, though at markedly different scales could dialectically converse with one another and through their mutual congruencies. In the final stage, the idea concludes contradictions across the scales to initiate the analogous roles of metamorphosed third reality, which suggests the previous un-acknowledged architectural or artistic identity. The proposed paper explores the trajectory of reproduction by analyzing drawings through detailed drawing stages and analyzes challenges as well as opportunities in the discovered realm of imagination. This description further aims at identifying factors influencing creativity and innovation in producing architectural drawings through the process of observing drawings from inception to the concluding stage.

Keywords: architectural drawings, metamorphosis, perceptions, discovery

Procedia PDF Downloads 77

Authors: Dewan Ali Ahsan

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Hilsa (Tenualosa ilisha) is one of the most important anadromous fish species of the trans-boundary ecosystem of Bangladesh, India and Myanmar. Hilsa is not only an economically important species specially for Bangladesh and India, but also for the integral part of the culture of the Bangladesh and India. This flag-ship species in Bangladesh contributed alone of 10.82% of the total fish production of the country and about 75% of world’s total catch of hilsa comes from Bangladesh alone. As hilsa is an anadromous fish, it migrates from the Bay of Bengal to rivers for spawning, nursing and growing and for all of these purposes hilsa needs freshwaters. Ripe broods prefer turbid, fast flowing freshwater for spawning but young prefer clear and slow flowing freshwater. Climate change (salinity intrusion, sea level rise, temperature rise, impact of fresh water flow), unplanned developmental activities and other anthropogenic activities all together are severely damaging the hilsa stock and its habitats. So, climate change and human interferences are predicted to have a range of direct and indirect impacts on marine and freshwater hilsa fishery, with implications for fisheries-dependent economies, coastal communities and fisherfolk. The present study identified that salinity intrusion, siltation in river bed, decrease water flow from upstream, fragmentation of river in dry season, over exploitation, use of small mesh nets are the major reasons to affect the upstream migration of hilsa and its sustainable management. It has been also noticed that Bangladesh government has taken some actions for hilsa management. Government is trying to increase hilsa production not only by conserving jatka (juvenile hilsa) but also protecting the brood hilsa during the breeding seasons by imposing seasonal ban on fishing, restricted mesh size etc. Unfortunately, no such management plans are available for Indian and Myanmar territory. As hilsa is a highly migratory trans-boundary fish in the Bay of Bengal (and all of these countries share the same stock), it is essential to adopt a joint management policy (by Bangladesh-India-Myanmar) for the sustainable management for the hilsa stock.

Keywords: hilsa, climate change, south-east Asia, fishery management

Procedia PDF Downloads 477

Authors: Mudasir Ahmad Syed, Raashid Ahmd Wani, Mashooq Ahmad Dar, Uneeb Urwat, Riaz Ahmad Shah, Nazir Ahmad Ganai

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Salmonella enterica serovar Typhimurium (Salmonella Typhimurium) is a primary avian pathogen responsible for severe intestinal pathology in younger chickens and economic losses. However, the Salmonella Typhimurium is also able to cause infection in humans, described by typhoid fever and acute gastro-intestinal disease. A study was conducted at days to investigate pathological, histopathological, haemato-biochemical, immunological and expression kinetics of NRAMP (natural resistance associated macrophage protein) gene family (NRAMP1 and NRAMP2) in broiler chickens following experimental infection of Salmonella Typhimurium at 0,1,3,5,7,9,11,13 and 15 days respectively. Infection was developed in birds through oral route at 2×108 CFU/ml. Clinical symptoms appeared 4 days post infection (dpi) and after one-week birds showed progressive weakness, anorexia, diarrhea and lowering of head. On postmortem examination, liver showed congestion, hemorrhage and necrotic foci on surface, while as spleen, lungs and intestines revealed congestion and hemorrhages. Histopathological alterations were principally observed in liver in second week post infection. Changes in liver comprised of congestion, areas of necrosis, reticular endothelial hyperplasia in association with mononuclear cell and heterophilic infiltration. Hematological studies confirm a significant decrease (P<0.05) in RBC count, Hb concentration and PCV. White blood cell count showed significant increase throughout the experimental study. An increase in heterophils was found up to 7dpi and a decreased pattern was observed afterwards. Initial lymphopenia followed by lymphocytosis was found in infected chicks. Biochemical studies showed a significant increase in glucose, AST and ALT concentration and a significant decrease (P<0.05) in total protein and albumin level in the infected group. Immunological studies showed higher titers of IgG in infected group as compared to control group. The real time gene expression of NRAMPI and NRAMP2 genes increased significantly (P<0.05) in infected group as compared to controls. The peak expression of NRAMP1 gene was seen in liver, spleen and caecum of infected birds at 3dpi, 5dpi and 7dpi respectively, while as peak expression of NRAMP2 gene in liver, spleen and caecum of infected chicken was seen at 9dpi, 5dpi and 9dpi respectively. This study has role in diagnostics and prognostics in the poultry industry for the detection of salmonella infections at early stages of poultry development.

Keywords: biochemistry, histopathology, NRAMP, poultry, real time expression, Salmonella Typhimurium

Procedia PDF Downloads 311