Search results for: mitigating CO2 emission

Authors: S. Abdulkadir, I. Y. Moh’d, S. U. Kunya, U. Nuruddeen

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The basis of any contract formation between the client and contractor is the budgeted cost and the estimated duration of projects. These variables are paramount important to project's sponsor in a construction projects and in assessing the success or viability of construction projects. Despite the availability of various techniques of cost and time control, many projects failed to achieve their initial estimated cost and time. The paper evaluate the inhibiting factors of cost and time control in Nigerian construction practice and comparing the result with the United Kingdom practice as identified by one researcher. The populations of the study are construction professionals within Bauchi and Gombe state, Nigeria, a judgmental sampling employed in determining the size of respondents. Descriptive statistics used in analyzing the data in SPSS. Design change, project fraud and corruption, financing and payment of completed work found to be common among the top five inhibiting factors of cost and time control in the study area. Furthermore, the result had shown some comprising with slight contrast as in the case of United Kingdom practice. Study recommend the adaptation of mitigation measures developed in the UK prior to assessing its effectiveness and so also developing a mitigating measure for other top factors that are not within the one developed in United Kingdom practice. Also, it recommends a wider assessing comparison on the modify inhibiting factors of cost and time control as revealed by the study to cover almost all part of Nigeria.

Keywords: comparison, cost, inhibiting factor, United Kingdom, time

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Authors: Sven Borén, Henrik Ny

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Ambitions within the EU for moving towards sustainable transport include major emission reductions for fossil fuel road vehicles, especially for buses, trucks, and cars. The electric driveline seems to be an attractive solution for such development. This study first applied the Framework for Strategic Sustainable Development to compare sustainability effects of today’s fossil fuel vehicles with electric vehicles that have batteries or hydrogen fuel cells. The study then addressed a scenario were electric vehicles might be in majority in Europe by 2050. The methodology called Strategic Lifecycle Assessment was first used, were each life cycle phase was assessed for violations against sustainability principles. This indicates where further analysis could be done in order to quantify the magnitude of each violation, and later to create alternative strategies and actions that lead towards sustainability. A Life Cycle Assessment of combustion engine cars, plug-in hybrid cars, battery electric cars and hydrogen fuel cell cars was then conducted to compare and quantify environmental impacts. The authors found major violations of sustainability principles like use of fossil fuels, which contribute to the increase of emission related impacts such as climate change, acidification, eutrophication, ozone depletion, and particulate matters. Other violations were found, such as use of scarce materials for batteries and fuel cells, and also for most life cycle phases for all vehicles when using fossil fuel vehicles for mining, production and transport. Still, the studied current battery and hydrogen fuel cell cars have less severe violations than fossil fuel cars. The life cycle assessment revealed that fossil fuel cars have overall considerably higher environmental impacts compared to electric cars as long as the latter are powered by renewable electricity. By 2050, there will likely be even more sustainable alternatives than the studied electric vehicles when the EU electricity mix mainly should stem from renewable sources, batteries should be recycled, fuel cells should be a mature technology for use in vehicles (containing no scarce materials), and electric drivelines should have replaced combustion engines in other sectors. An uncertainty for fuel cells in 2050 is whether the production of hydrogen will have had time to switch to renewable resources. If so, that would contribute even more to a sustainable development. Except for being adopted in the GreenCharge roadmap, the authors suggest that the results can contribute to planning in the upcoming decades for a sustainable increase of EVs in Europe, and potentially serve as an inspiration for other smaller or larger regions. Further studies could map the environmental effects in LCA further, and include other road vehicles to get a more precise perception of how much they could affect sustainable development.

Keywords: strategic, electric vehicles, sustainability, LCA

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Authors: R. H. Bari

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The nanostructured thin films of CdSnO3 are sensitive to change in their environment. CdSnO3 is successfully used as gas sensor due to the dependence of the electrical conductivity on the ambient gas composition. Nanostructured CdSnO3 thin films of different substrate temperature (300 0C, 350 0C, 400 0C and 450 0C) were deposited onto heated glass substrate by simple spray pyrolysis (SP) technique. Sensing elements of nanostructured CdSnO3 were annealed at 500 0C for 1 hrs. Characterization includes a different analytical technique such as, X-ray diffractogram (XRD), energy dispersive X-ray analysis (EDAX), and Field emission scanning electron microscope (FE-SEM). The average grain size observed from XRD and FF-SEM was found to be less than 18.36 and 23 nm respectively. The films sprayed at substrate temperature for 400 0C was observed to be most sensitive (S = 530) to SO2 for 500 ppm at 300 0C. The response and recovery time is 4 sec, 8 sec respectively.

Keywords: nanostructured CdSnO3, spray pyrolysis, SO2 gas sensing, quick response

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Authors: Aliyu Mohammed Lawal, Dahiru Ya'u Gital

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The problems placed on the environment as a result of energy generation and usage in Nigeria are: Potential damage to the environment health by Co, Co2, Sox and Nox effluent gas emissions and global warming. For instance in the year 2004 in Nigeria energy consumption was 58% oil and 34% natural gas but about 94 million metric tons of Co2 was emitted out of which 64% came from fossil fuels while about 35% came from fuel wood. The findings from this research on how to alleviate these problems are that long term sustainable development solutions should be enhanced globally; energy should be used more rationally renewable energy resources should be exploited and the existing emissions should be controlled to tolerate limits because the increase in energy demand in Nigeria places enormous strain on current energy facilities.

Keywords: energy generation, environmental health, effluent gas emission, global warming, fossil fuel

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Authors: Elkington Sibusiso Mnguni

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In South Africa, mining has been a key economic sector since the discovery of gold in 1886 in the Witwatersrand region, where the city of Johannesburg is located. However, some mines have since been decommissioned, and the continuous pumping of acid mine drainage (AMD) also stopped causing the AMD to rise towards the ground surface. This posed a serious environmental risk to the groundwater resources and river systems in the region. This paper documents the development and extent of the environmental damage as well as the measures implemented by the government to alleviate such damage. The study will add to the body of knowledge on the subject of AMD treatment to prevent environmental degradation. The method used to gather and collate relevant data and information was the desktop study. The key findings include the social and environmental impact of the AMD, which include the pollution of water sources for domestic use leading to skin and other health problems and the loss of biodiversity in some areas. It was also found that the technical intervention of constructing a plant to pump and treat the AMD using the high-density sludge technology was the most effective short-term solution available while a long-term solution was being explored. Some successes and challenges experienced during the implementation of the project are also highlighted. The study will be a useful record of the current status of the AMD treatment interventions in the region.

Keywords: acid mine drainage, groundwater resources, pollution, river systems, technical intervention, high density sludge

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Authors: M. S. Stepanova, V. V. Zakharov, P. D. Khavlyuk, I. D. Skurlov, A. Y. Dubovik, A. L. Rogach

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Carbon dots are small carbon-based spherical nanoparticles, which are typically less than 10 nm in size that can be modified with surface passivation and heteroatoms doping. The light-absorbing ability of carbon dots has attracted a significant amount of attention in photoluminescence for bioimaging and fluorescence sensing applications owing to their advantages, such as tunable fluorescence emission, photo- and thermostability and low toxicity. In this study, carbon dots were synthesized by the solvothermal method from citric acid and ethylenediamine dissolved in water. The solution was heated for 5 hours at 200°C and then cooled down to room temperature. The carbon dots films were obtained by evaporation from a high-concentration aqueous solution. The increase of both luminescence intensity and light transmission was obtained as a result of a 405 nm laser exposure to a part of the carbon dots film, which was detected using a confocal laser scanning microscope (LSM 710, Zeiss). Blueshift up to 35 nm of the luminescence spectrum is observed as luminescence intensity, which is increased more than twofold. The exact value of the shift depends on the time of the laser exposure. This shift can be caused by the modification of surface groups at the carbon dots, which are responsible for long-wavelength luminescence. In addition, a shift of the absorption peak by 10 nm and a decrease in the optical density at the wavelength of 350 nm is detected, which is responsible for the absorption of surface groups. The obtained sample was also studied with time-resolved confocal fluorescence microscope (MicroTime 100, PicoQuant), which made it possible to receive a time-resolved photoluminescence image and construct emission decays of the laser-exposed and non-exposed areas. 5 MHz pulse rate impulse laser has been used as a photoluminescence excitation source. Photoluminescence decay was approximated by two exhibitors. The laser-exposed area has the amplitude of the first-lifetime component (A1) twice as much as before, with increasing τ1. At the same time, the second-lifetime component (A2) decreases. These changes evidence a modification of the surface groups of carbon dots. The detected effect can be used to create thermostable fluorescent marks, the physical size of which is bounded by the diffraction limit of the optics (~ 200-300 nm) used for exposure and to improve the optical properties of carbon dots or in the field of optical encryption. Acknowledgements: This work was supported by the Ministry of Science and Higher Education of Russian Federation, goszadanie no. 2019-1080 and financially supported by Government of Russian Federation, Grant 08-08.

Keywords: carbon dots, photoactivation, optical properties, photoluminescence and absorption spectra

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Authors: Terry Lucas

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Calculations are performed to quantify the potential contribution of each greenhouse gas emission reduction strategy. This approach facilitates the visualisation of the relative benefits of each, and it provides a potential baseline for the development of a plan of action that is rooted in quantitative evaluation. Emissions reductions are converted to potential de-escalation of global average temperature. A comprehensive plan is then presented which shows the potential benefits all the way out to year 2100. A target temperature de-escalation of 2oC was selected, but the plan shows a benefit of only 1.225oC. This latter disappointing result is in spite of new and powerful technologies introduced into the equation. These include nuclear fusion and alternative nuclear fission processes. Current technologies such as wind, solar and electric vehicles show surprisingly small constributions to the whole.

Keywords: climate change, emissions, drawdown, energy

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Authors: J. I. Santos, A. E. Cesarin, C. A. R. Sales, M. B. B. Triano, P. F. R. B. Martins, A. F. Braga, N. J. Neto, A., A. M. Barroso, P. L. C. A. Alves, C. A. M. Huaman

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Climate change projections based on the emission of greenhouse effect gases suggest an increase in the concentration of atmospheric carbon dioxide, in up to 750 ppm. In this scenario, we have significant changes in plant development, and consequently, in agricultural systems. This study aims to evaluate the interaction between culture (Glycine max) and weed (Amaranthus viridis and Euphorbia heterophylla) in two conditions of CO₂, 400 and 800 ppm. The results showed that the coexistence of culture with both weed species resulted in a mutual loss, with decrease in dry mass productivity of culture + weeds, in both conditions of CO₂. However, when the culture is grown in association with E. heterophylla, total dry mass of culture + weed was smaller at 800 ppm. Soybean was more aggressive in comparison to the A. viridis in both the concentrations of CO₂, but not in relation to the E. heterophylla.

Keywords: plants interaction, increase of [CO₂], plants of metabolismo C3, glycine max

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Authors: S. S. Nafee, A. M. Al-Ramady, S. A. Shaheen

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Evaluated nuclear decay data for the 217Po nuclide ispresented in the present work. These data include recommended values for the half-life T1/2, α-, β--, and γ-ray emission energies and probabilities. Decay data from 221Rn α and 217Bi β—decays are presented. Q(α) has been updated based on the recent published work of the Atomic Mass Evaluation AME2012. In addition, the logft values were calculated using the Logft program from the ENSDF evaluation package. Moreover, the total internal conversion electrons has been calculated using Bricc program. Meanwhile, recommendation values or the multi-polarities have been assigned based on recently measurement yield a better intensity balance at the 254 keV and 264 keV gamma transitions.

Keywords: nuclear decay data evaluation, mass evaluation, total converison coefficients, atomic mass evaluation

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Authors: Boulis M. Ibrahim, Iordanis A. Kalaitzoglou

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A micro structural pricing model is proposed in which price components account for learning by incorporating changing expectations of the trading intensity and the risk level of incoming trades. An analysis of European carbon futures transactions finds expected trading intensity to increase the information component and decrease the liquidity component of price changes, but at different rates. Among the results, the expected persistence in trading intensity explains the majority of the auto correlations in the level and the conditional volatility of price changes, helps predict hourly patterns in the bid–ask spread and differentiates between the impact of buy versus sell and continuing versus reversing trades.

Keywords: CO2 emission allowances, market microstructure, duration, price discovery

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Authors: Denis Jordan, Daniel Golkowski, Mathias Lukas, Katharina Merz, Caroline Mlynarcik, Max Maurer, Valentin Riedl, Stefan Foerster, Eberhard F. Kochs, Andreas Bender, Ruediger Ilg

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Introduction: So far, clinical assessments that rely on behavioral responses to differentiate coma states or even predict outcome in coma patients are unreliable, e.g. because of some patients’ motor disabilities. The present study was aimed to provide prognosis in coma patients using markers from electroencephalogram (EEG), blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI) and [18F]-fluorodeoxyglucose (FDG) positron emission tomography (PET). Unsuperwised principal component analysis (PCA) was used for multimodal integration of markers. Methods: Approved by the local ethics committee of the Technical University of Munich (Germany) 20 patients (aged 18-89) with severe brain damage were acquired through intensive care units at the Klinikum rechts der Isar in Munich and at the Therapiezentrum Burgau (Germany). At the day of EEG/fMRI/PET measurement (date I) patients (<3.5 month in coma) were grouped in the minimal conscious state (MCS) or vegetative state (VS) on the basis of their clinical presentation (coma recovery scale-revised, CRS-R). Follow-up assessment (date II) was also based on CRS-R in a period of 8 to 24 month after date I. At date I, 63 channel EEG (Brain Products, Gilching, Germany) was recorded outside the scanner, and subsequently simultaneous FDG-PET/fMRI was acquired on an integrated Siemens Biograph mMR 3T scanner (Siemens Healthineers, Erlangen Germany). Power spectral densities, permutation entropy (PE) and symbolic transfer entropy (STE) were calculated in/between frontal, temporal, parietal and occipital EEG channels. PE and STE are based on symbolic time series analysis and were already introduced as robust markers separating wakefulness from unconsciousness in EEG during general anesthesia. While PE quantifies the regularity structure of the neighboring order of signal values (a surrogate of cortical information processing), STE reflects information transfer between two signals (a surrogate of directed connectivity in cortical networks). fMRI was carried out using SPM12 (Wellcome Trust Center for Neuroimaging, University of London, UK). Functional images were realigned, segmented, normalized and smoothed. PET was acquired for 45 minutes in list-mode. For absolute quantification of brain’s glucose consumption rate in FDG-PET, kinetic modelling was performed with Patlak’s plot method. BOLD signal intensity in fMRI and glucose uptake in PET was calculated in 8 distinct cortical areas. PCA was performed over all markers from EEG/fMRI/PET. Prognosis (persistent VS and deceased patients vs. recovery to MCS/awake from date I to date II) was evaluated using the area under the curve (AUC) including bootstrap confidence intervals (CI, *: p<0.05). Results: Prognosis was reliably indicated by the first component of PCA (AUC=0.99*, CI=0.92-1.00) showing a higher AUC when compared to the best single markers (EEG: AUC<0.96*, fMRI: AUC<0.86*, PET: AUC<0.60). CRS-R did not show prediction (AUC=0.51, CI=0.29-0.78). Conclusion: In a multimodal analysis of EEG/fMRI/PET in coma patients, PCA lead to a reliable prognosis. The impact of this result is evident, as clinical estimates of prognosis are inapt at time and could be supported by quantitative biomarkers from EEG, fMRI and PET. Due to the small sample size, further investigations are required, in particular allowing superwised learning instead of the basic approach of unsuperwised PCA.

Keywords: coma states and prognosis, electroencephalogram, entropy, functional magnetic resonance imaging, machine learning, positron emission tomography, principal component analysis

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Authors: Sarah Abdourraziq, Rachid El Bachtiri

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The solar power source for pumping water is one of the most promising areas in photovoltaic applications. The implementation of these systems allows to protect the environment and reduce the CO₂ gas emission compared to systems trained by diesel generators. This paper presents a comparative study between the photovoltaic pumping system driven by DC motor, and AC motor to define the optimum design of this application. The studied system consists of PV array, DC-DC Boost Converter, inverter, motor-pump set and storage tank. The comparison was carried out to define the characteristics and the performance of each system. Each subsystem is modeled in order to simulate the whole system in MATLAB/ Simulink. The results show the efficiency of the proposed technique.

Keywords: photovoltaic water pumping system, DC motor-pump, AC motor-pump, DC-DC boost converter

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Authors: Lee Chiau Yeng, Norhayani Othman

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Regenerated cellulose fiber is fabricated in the NaOH/urea aqueous solution. In this work, cellulose is dissolved in 7 .wt% NaOH/12 .wt% urea in the temperature of -12 °C to prepare regenerated cellulose. Thermal and structure properties of cellulose and regenerated cellulose was compared and investigated by Field Emission Scanning Electron Microscopy (FeSEM), Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), Thermogravimetric analysis (TGA), and Differential Scanning Calorimetry. Results of FeSEM revealed that the regenerated cellulose fibers showed a more circular shape with irregular size due to fiber agglomeration. FTIR showed the difference in between the structure of cellulose and the regenerated cellulose fibers. In this case, regenerated cellulose fibers have a cellulose II crystalline structure with lower degree of crystallinity. Regenerated cellulose exhibited better thermal stability than the cellulose.

Keywords: regenerated cellulose, cellulose, NaOH, urea

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Authors: Metin Kömsöken, Ayşe Güneş Tanır, Onur Karaman

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Usage of high energy charged particles for diagnosis and treatment has been widespread in medicine. The main purpose is to investigate that Bremsstrahlung which occurs by tissue interactions with charged particles should not be neglected. Nuclear stopping power (Bremsstrahlung) was calculated for lung, brain, skin, muscle, bone (cortical) and water targets for the energies of electrons obtained from LINAC used in radiotherapy and of β+ sources used in positron emission tomography (PET). These calculations were done by using the four different analytical functions including classical Bethe-Bloch, Tsoulfanidis, modified Bethe-Bloch and modified Tsoulfanidis equations. It was concluded that obtained results were compatible with that of National Institute of Standards and Technology (NIST-ESTAR).

Keywords: β- emitting source, bremsstrahlung, therapeutic radionuclides, LINAC

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Authors: Kious Mecheri, Hadjadj Abdechafik, Ameur Aissa

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The wear of cutting tool degrades the quality of the product in the manufacturing processes. The online monitoring of the cutting tool wear level is very necessary to prevent the deterioration of the quality of machining. Unfortunately there is not a direct manner to measure the cutting tool wear online. Consequently we must adopt an indirect method where wear will be estimated from the measurement of one or more physical parameters appearing during the machining process such as the cutting force, the vibrations, or the acoustic emission etc. In this work, a neural network system is elaborated in order to estimate the flank wear from the cutting force measurement and the cutting conditions.

Keywords: flank wear, cutting forces, high speed milling, signal processing, neural network

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Authors: Atena Tazikeh Lemeski, Ismail Ozdamar

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This study presents a detailed analysis of harmonic distortion in a grid-connected photovoltaic (PV) system using real-time data captured from a solar power plant. Harmonics introduced by inverters in PV systems can degrade power quality and lead to increased Total Harmonic Distortion (THD), which poses challenges such as transformer overheating, increased power losses, and potential grid instability. This research addresses these issues by applying Fast Fourier Transform (FFT) to identify significant harmonic components and employing notch filters to target specific frequencies, particularly the 3rd harmonic (150 Hz), which was identified as the largest contributor to THD. Initial analysis of the unfiltered voltage signal revealed a THD of 21.15%, with prominent harmonic peaks at 150 Hz, 250 Hz and 350 Hz, corresponding to the 3rd, 5th, and 7th harmonics, respectively. After implementing the notch filters, the THD was reduced to 5.72%, demonstrating the effectiveness of this approach in mitigating harmonic distortion without affecting the fundamental frequency. This paper provides practical insights into the application of real-time filtering techniques in PV systems and their role in improving overall grid stability and power quality. The results indicate that targeted harmonic mitigation is crucial for the sustainable integration of renewable energy sources into modern electrical grids.

Keywords: grid-connected photovoltaic systems, fast Fourier transform, harmonic filtering, inverter-induced harmonics

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Authors: Mahadzirah Mohamad, Morliyati Mohammad, Nor Azman Mat Ali, Zainudin Awang

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Globally, youth substance abuse has been identified as the problem that causes substantial damage not only to individuals, but also to families and communities. In addition, substance abuse youths have become unproductive resources that would play lesser roles in the nation’s development. The increasing trend of substance abuse among youths has raised a lot of concern among various quarters in Malaysia. It has also been reported that Malay youths are the majority group involved in substance abuse. However, it was noted that life satisfaction had been found to be an important mitigating factor that addressed substance abuse. The objectives of the study were twofold: firstly, to ascertain the effect of life satisfaction on substance abuse among Malay youth. Secondly, to identify the role of delinquency on the relationship between life satisfaction and substance abuse. This study adopted a cross-sectional research design. Self-administered questionnaires were distributed to 500 Malay youths at the youth programmes using a two-step sampling technique: area sampling and systematic sampling. The research hypotheses were tested using Structural Equation Modelling. The findings of the study revealed that there is no significance relationship between life satisfaction and substance abuse. There is a significant inverse relationship between life satisfaction and delinquency. Moreover, delinquency has a positive significant influence on substance abuse. The use of Bootstrapping analysis proved that delinquency plays a full mediating role in the relationship between life satisfaction and substance abuse. This study suggested that life satisfaction has no effect on youth substance abuse. In order to reduce substance abuse, efforts should be undertaken to reduce delinquency behaviour by increasing youth life satisfaction.

Keywords: delinquency, life satisfaction, substance abuse, youth

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Authors: Azeez Shaik, Yagnik Kalariya, Amit Salvi

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High-performance requirements and emission norms were forcing the automobile industry to opt for lightweight materials which improve the fuel efficiency and absorb energy during crash applications. In such scenario, the woven fabric composites are providing better energy absorption compared to metals. Woven fabric composites have a repetitive unit cell (RUC) and the mechanical properties of these materials are highly dependent on RUC. This work investigates the importance of detailed modelling of the RUC, the size effects associated and the mitigation techniques to avoid them using Finite element analysis approach.

Keywords: repetitive unit cell, representative volume element, size effects, cohesive zone, finite element analysis

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Authors: M. H. Al-Mansoori, W. S. Al-Ghaithi, F. N. Hasoon

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In this paper, we experimentally investigate the performance of an efficient high gain triple-pass L-band Erbium-Doped Fiber (EDF) amplifier structure with a single pump source. The amplifier gain and noise figure variation with EDF pump power, input signal power and wavelengths have been investigated. The generated backward Amplified Spontaneous Emission (ASE) noise of the first amplifier stage is suppressed by using a tunable band-pass filter. The amplifier achieves a signal gain of 55 dB with low noise figure of 3.8 dB at -50 dBm input signal power. The amplifier gain shows significant improvement of 12.8 dB compared to amplifier structure without ASE suppression.

Keywords: optical amplifiers, EDFA, L-band, optical networks

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Authors: Elizabeth O. Odewale, Sachithra T. Wanasinghe, Aaron S. Rury

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Cavity polaritons form when molecular excitons strongly couple to photons in carefully constructed optical cavities. These polaritons, which are hybrid light-matter states possessing a unique combination of photonic and excitonic properties, present the opportunity to manipulate the properties of various semiconductor materials. The systematic manipulation of materials through polariton formation could potentially improve the functionalities of many optoelectronic devices such as lasers, light-emitting diodes, photon-based quantum computers, and solar cells. However, the prospects of leveraging polariton formation for novel devices and device operation depend on more complete connections between the properties of molecular chromophores, and the hybrid light-matter states they form, which remains an outstanding scientific goal. Specifically, for most optoelectronic applications, it is paramount to understand how polariton formation affects the spectra of light absorbed by molecules coupled strongly to cavity photons. An essential feature of a polariton state is its dispersive energy, which occurs due to the enhanced spatial delocalization of the polaritons relative to bare molecules. To leverage the spatial delocalization of cavity polaritons, angle-resolved photoluminescence excitation spectroscopy was employed in characterizing light emission from the polaritonic states. Using lasers of appropriate energies, the polariton branches were resonantly excited to understand how molecular light absorption changes under different strong light-matter coupling conditions. Since an excited state has a finite lifetime, the photon absorbed by the polariton decays non-radiatively into lower-lying molecular states, from which radiative relaxation to the ground state occurs. The resulting fluorescence is collected across several angles of excitation incidence. By modeling the behavior of the light emission observed from the lower-lying molecular state and combining this result with the output of angle-resolved transmission measurements, inferences are drawn about how the behavior of molecules changes when they form polaritons. These results show how the intrinsic properties of molecules, such as the excitonic lifetime, affect the rate at which the polaritonic states relax. While it is true that the lifetime of the photon mediates the rate of relaxation in a cavity, the results from this study provide evidence that the lifetime of the molecular exciton also limits the rate of polariton relaxation.

Keywords: flourescece, molecules in cavityies, optical cavity, photoluminescence excitation, spectroscopy, strong coupling

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Authors: Ines Antunes, Andrea Massari, Concetta Bartucca

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Greenhouse gasses (GHG) role in the atmosphere has been well known since the 19th century; however, researchers have begun to relate them to climate changes only in the second half of the following century. From this moment, scientists started to correlate the presence of GHG such as CO₂ with the global warming phenomena. This has raised the awareness not only of those who were experts in this field but also of public opinion, which is becoming more and more sensitive to environmental pollution and sustainability issues. Nowadays the reduction of GHG emissions is one of the principal objectives of EU nations. The target is an 80% reduction of emissions in 2050 and to reach the important goal of carbon neutrality. Road sector is responsible for an important amount of those emissions (about 20%). The most part is due to traffic, but a good contribution is also given directly or indirectly from road construction and maintenance. Raw material choice and reuse of post-consumer plastic rather than a cleverer design of roads have an important contribution to reducing carbon footprint. Bituminous membranes can be successfully used as reinforcement systems in asphalt layers to improve road pavement performance against cracking. Composite materials coupling membranes with grids and/or fabrics should be able to combine improved tensile properties of the reinforcement with stress absorbing and waterproofing effects of membranes. Polyglass, with its brand dedicated to road construction and maintenance called Polystrada, has done more than this. The company's target was not only to focus sustainability on the final application but also to implement a greener mentality from the cradle to the grave. Starting from production, Polyglass has made important improvements finalized to increase efficiency and minimize waste. The installation of a trigeneration plant and the usage of selected production scraps inside the products as well as the reduction of emissions into the environment, are one of the main efforts of the company to reduce impact during final product build-up. Moreover, the benefit given by installing Polystrada products brings a significant improvement in road lifetime. This has an impact not only on the number of maintenance or renewal that needs to be done (build less) but also on traffic density due to works and road deviation in case of operations. During the end of the life of a road, Polystrada products can be 100% recycled and milled with classical systems used without changing the normal maintenance procedures. In this work, all these contributions were quantified in terms of CO₂ emission thanks to an LCA analysis. The data obtained were compared with a classical system or a standard production of a membrane. What it is possible to see is that the usage of Polyglass products for street maintenance and building gives a significant reduction of emissions in case of membrane installation under the road wearing course.

Keywords: CO₂ emission, LCA, maintenance, sustainability

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Authors: R. Chedid, R. Ghajar

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Lebanon electricity crisis continues to escalate. Rationing hours still apply across the country but with different rates. The capital Beirut is subjected to 3 hours cut while other cities, town and villages may endure 9 to 14 hours of power shortage. To mitigate this situation, private diesel generators distributed illegally all over the country are being used to bridge the gap in power supply. Almost each building in large cities has its own generator and individual villages may have more than one generator supplying their loads. These generators together with their private networks form incomplete and ill-designed and managed microgrids (MG) but can be further developed to become renewable energy-based MG operating in island- or grid-connected modes. This paper will analyze the potential of introducing MG to help resolve the energy crisis in Lebanon. It will investigate the usefulness of developing MG under the prevailing situation of existing private power supply service providers and in light of the developed national energy policy that supports renewable energy development. A case study on a distribution feeder in a rural area will be analyzed using HOMER software to demonstrate the usefulness of introducing photovoltaic (PV) arrays along the existing diesel generators for all the stakeholders; namely, the developers, the customers, the utility and the community at large. Policy recommendations regarding MG development in Lebanon will be presented on the basis of the accumulated experience in private generation and the privatization and public-private partnership laws.

Keywords: decentralized systems, distributed generation, microgrids, renewable energy

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Authors: Tochukwu Timothy Okoli, Devi Datt Tewari

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The high rate of Fintech adoption has not transmitted to greater financial inclusion and development in Africa. This problem is attributed to poor Fintech diversification and usefulness in the continent. This concept is referred to as the Fintech depth of penetration in this study. The study, therefore, assessed its determinants and growth process in a panel of three emergings, twenty-four frontiers and five fragile African economies disaggregated with dummies over the period 2004-2018 to allow for heterogeneity between groups. The System Generalized Method of Moments (GMM) technique reveals that the average depth of Mobile banking and automated teller machine (ATM) is a dynamic heterogeneity process. Moreover, users' previous experiences/compatibility, trial-ability/income, and financial development were the major factors that raise its usefulness, whereas perceived risk, financial openness, and inflation rate significantly limit its usefulness. The growth rate of Mobile banking, ATM, and Internet banking in 2018 is, on average 41.82, 0.4, and 20.8 per cent respectively greater than its average rates in 2004. These greater averages after the 2009 financial crisis suggest that countries resort to Fintech as a risk-mitigating tool. This study, therefore, recommends greater Fintech diversification through improved literacy, institutional development, financial liberalization, and continuous innovation.

Keywords: depth of fintech, emerging Africa, financial technology, internet banking, mobile banking

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Authors: Bhrigu Rishi Mishra, Sreerag Sundaram, Nithin Jo Varghese, Karthik Sasihithlu

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We have designed a TiO2/PDMS coating with 94% solar reflection, 96% IR emission, and 81.8 W/m2 cooling power for passive daytime radiative cooling using Kubelka Munk theory and CST microwave studio. To reduce solar absorption loss in 0.3-0.39 m wavelength region, a TiO2 thin film on top of the coating is used. Simulation using Ansys Lumerical shows that for a 20 m thick TiO2/PDMS coating, a TiO2 thin film of 84 nm increases the coating's reflectivity by 11% in the solar region.

Keywords: passive daytime radiative cooling, disordered metamaterial, Kudelka Munk theory, solar reflectivity

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Authors: Adria Rae Abigail R. Eda, Arvin C. Diesmos, Vance T. Vredenburg, Merab A. Chan

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Mitigating strategies using symbiotic cutaneous bacteria is one of the major concerns in the conservation of amphibian population. Batrachochytrium dendrobatidis is the causative agent of chytridiomycosis associated with mass mortality and amphibian extinctions worldwide. In the Philippines, there is a lack of study on the cutaneous bacteria of Philippine amphibians that may have beneficial effects to ward off the deadly fungal infection. In this study, cutaneous bacteria from frogs were isolated and examined for anti-B. dendrobatidis activity. Eight species of frogs were collected at Mt. Palay-palay Mataas na Gulod National Park in Cavite, a site positive for the presence of B. dendrobatidis. Bacteria were isolated from the skin of frogs by swabbing the surfaces of the body and inoculated in Reasoner´s 2A (R2A) agar. Isolated bacteria were tested for potential inhibitory properties against B. dendrobatidis through zoospore inhibition assay. Results showed that frog cutaneous bacteria significantly inhibited the growth of B. dendrobatidis in vitro. By means of 16S rRNA gene primers, the anti-B. dendrobatidis bacteria were identified to be Enterobacter sp., Alcaligenes faecalis and Pseudomonas sp. Cutaneous bacteria namely Enterobacter sp. (isolates PLd33 and PCv4) and Pseudomonas (isolate PLd31) remarkably cleared the growth of B. dendrobatidis zoospore in 1% tryptone agar. Therefore, frog cutaneous bacteria inhibited B. dendrobatidis in vitro and could possibly contribute to the immunity and defense of frogs against the lethal chytridiomycosis.

Keywords: Batrachochytrium dendrobatidis, cutaneous bacteria, frogs, zoospore inhibition assay

Procedia PDF Downloads 454

Authors: Mohamed Khedr, Ahmed Farghali, Waleed El Rouby, Abdelrhman Hamdeldeen

Abstract:

Pure CeO2, Sm and Gd doped CeO2 were successfully prepared via hydrothermal method. The effect of hydrothermal temperature, reaction time and precursors were investigated. The prepared nanoparticles were characterized using X-ray diffraction (XRD), FT-Raman Spectroscopy, transmission electron microscope (TEM) and field emission scanning electron microscope (FESEM). The prepared pure and doped CeO2 nanoparticles were used as photo-catalyst for the degradation of Methylene blue (MB) dye under UV light irradiation. The results showed that Gd doped CeO2 nano-particles have the best catalytic degradation effect for MB under UV irradiation. The degradation pathways of MB were followed using liquid chromatography (LC/MS) and it was found that Gd doped CeO2 was able to oxidize MB dye with a complete mineralization of carbon, nitrogen and sulfur heteroatoms into CO2, NH4+, NO3- and SO42-.

Keywords: CeO2, doped CeO2, photocatalysis, methylene blue

Procedia PDF Downloads 328

Authors: Nur A. Özdemir, Sude Erkin, Hatice K. Güney, Cemre S. Atılgan, Enes Huylu, Hüseyin Y. Altıntaş, Aysemin Top, Özak Durmuş

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Carbon emissions produced during a product’s life cycle, from extraction of raw materials up to waste disposal and market consumption activities are the major contributors to global warming. In the light of the science-based targets (SBT) leading the way to a zero-carbon economy for sustainable growth of the companies, carbon footprint reporting of the purchased goods has become critical for identifying hotspots and best practices for emission reduction opportunities. In line with Ford Otosan's corporate sustainability strategy, research was conducted to evaluate the carbon footprint of purchased products in accordance with Scope 3 of the Greenhouse Gas Protocol (GHG). The purpose of this paper is to develop a systematic and transparent methodology to calculate carbon footprint of the products produced by automotive OEMs (Original Equipment Manufacturers) within the context of automobile supply chain management. To begin with, primary material data were collected through IMDS (International Material Database System) corresponds to company’s three distinct types of vehicles including Light Commercial Vehicle (Courier), Medium Commercial Vehicle (Transit and Transit Custom), Heavy Commercial Vehicle (F-MAX). Obtained material data was classified as metals, plastics, liquids, electronics, and others to get insights about the overall material distribution of produced vehicles and matched to the SimaPro Ecoinvent 3 database which is one of the most extent versions for modelling material data related to the product life cycle. Product life cycle analysis was calculated within the framework of ISO 14040 – 14044 standards by addressing the requirements and procedures. A comprehensive literature review and cooperation with suppliers were undertaken to identify the production methods of parts used in vehicles and to find out the amount of scrap generated during part production. Cumulative weight and material information with related production process belonging the components were listed by multiplying with current sales figures. The results of the study show a key modelling on carbon footprint of products and processes based on a scientific approach to drive sustainable growth by setting straightforward, science-based emission reduction targets. Hence, this study targets to identify the hotspots and correspondingly provide broad ideas about our understanding of how to integrate carbon footprint estimates into our company's supply chain management by defining convenient actions in line with climate science. According to emission values arising from the production phase including raw material extraction and material processing for Ford OTOSAN vehicles subjected in this study, GHG emissions from the production of metals used for HCV, MCV and LCV account for more than half of the carbon footprint of the vehicle's production. Correspondingly, aluminum and steel have the largest share among all material types and achieving carbon neutrality in the steel and aluminum industry is of great significance to the world, which will also present an immense impact on the automobile industry. Strategic product sustainability plan which includes the use of secondary materials, conversion to green energy and low-energy process design is required to reduce emissions of steel, aluminum, and plastics due to the projected increase in total volume by 2030.

Keywords: automotive, carbon footprint, IMDS, scope 3, SimaPro, sustainability

Procedia PDF Downloads 108

Authors: Mary Funke Olabanji, Thando Ndarana, Nerhene Davis, Sylvester Okechukwu Ilo

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Scientific evidence indicates that climate change is already being experienced by farmers, and its impacts are felt on agricultural and food systems. Understanding the perceptions of farmers on climate change and how they respond to this change is essential to the development and implementation of appropriate policies for agriculture and food security. This paper aims to contribute to the understanding of farmers’ perceptions of climate change, adopted coping strategies, long-term implications of their adaptation choices, and barriers to their decisions to adapt. Data were randomly collected from 73 respondents in five districts located in the Olifants catchment of South Africa. A combination of descriptive statistics and Chi-Square statistical tests using the Statistical Package for Social Science (SPSS) was used to analyse the data obtained from the survey. Results show that smallholder farmers have an in-depth perception of climate change. The most significant changes perceived by farmers were increased temperature and low rainfall. The results equally revealed that smallholder farmers in the Olifants catchment had adopted several adaptation strategies in response to the perceived climate change. The significant adaptation strategies from the results include changing cropping patterns and planting date, use of improved seed variety, and chemical fertilizers. The study, therefore, concludes that crop diversification and agroforestry were more effective and sustainable in mitigating the impact of climate change.

Keywords: adaptation, climate change, perception, smallholder farmers

Procedia PDF Downloads 182

Authors: Saidu I. R., Shittu S. S.

Abstract:

As the trend of personal devices accessing corporate data continues to rise through Bring Your Own Device (BYOD) practices, organizations recognize the potential cost reduction and productivity gains. However, the associated security risks pose a significant threat to these benefits. Often, organizations adopt BYOD environments without fully considering the vulnerabilities introduced by human factors in this context. This study presents an enhanced assessment model that evaluates the security posture of employees in BYOD environments using cyber hygiene principles. The framework assesses users' adherence to best practices and guidelines for maintaining a secure computing environment, employing scales and the Euclidean distance formula. By utilizing this algorithm, the study measures the distance between users' security practices and the organization's optimal security policies. To facilitate user evaluation, a simple and intuitive interface for automated assessment is developed. To validate the effectiveness of the proposed framework, design science research methods are employed, and empirical assessments are conducted using five artifacts to analyze user suitability in BYOD environments. By addressing the human factor vulnerabilities through the assessment of cyber hygiene practices, this study aims to enhance the overall security of BYOD environments and enable organizations to leverage the advantages of this evolving trend while mitigating potential risks.

Keywords: security, BYOD, vulnerability, risk, cyber hygiene

Procedia PDF Downloads 76

Authors: B. R. Raut

Abstract:

The seismic performance of 20-storey benchmark building with semi-active dampers is investigated under various earthquake ground motions. The Semi-Active Variable Friction Dampers (SAVFD) and Magnetorheological Dampers (MR) are used in this study. A recently proposed predictive control algorithm is employed for SAVFD and a simple mechanical model based on a Bouc–Wen element with clipped optimal control algorithm is employed for MR damper. A parametric study is carried out to ascertain the optimum parameters of the semi-active controllers, which yields the minimum performance indices of controlled benchmark building. The effectiveness of dampers is studied in terms of the reduction in structural responses and performance criteria. To minimize the cost of the dampers, the optimal location of the damper, rather than providing the dampers at all floors, is also investigated. The semi-active dampers installed in benchmark building effectively reduces the earthquake-induced responses. Lesser number of dampers at appropriate locations also provides comparable response of benchmark building, thereby reducing cost of dampers significantly. The effectiveness of two semi-active devices in mitigating seismic responses is cross compared. Among two semi-active devices majority of the performance criteria of MR dampers are lower than SAVFD installed with benchmark building. Thus the performance of the MR dampers is far better than SAVFD in reducing displacement, drift, acceleration and base shear of mid to high-rise building against seismic forces.

Keywords: benchmark building, control strategy, input excitation, MR dampers, peak response, semi-active variable friction dampers

Procedia PDF Downloads 285