Search results for: losses

Authors: R. S. Arun Raj

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In today's climate of growing energy needs and increasing environmental issues, alternatives to the use of non-renewable and polluting fossil fuels have to be investigated. One such alternative is the solar energy. The SUN provides every hour as much energy as mankind consumes in one year. This paper clearly explains about the solar panel design and new models and methodologies that can be implemented for better utilization of solar energy. Minimisation of losses in solar panel as heat is my innovative idea revolves around. The pay back calculations by implementation of solar panels is also quoted.

Keywords: on-grid and off-grid systems, pyro-electric effect, pay-back calculations, solar panel

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Authors: D. Ramajo, S. Corzo, M. Nigro

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A Multi-dimensional computational fluid dynamics (CFD) two-phase model was developed with the aim to simulate the in-core coolant circuit of a pressurized heavy water reactor (PHWR) of a commercial nuclear power plant (NPP). Due to the fact that this PHWR is a Reactor Pressure Vessel type (RPV), three-dimensional (3D) detailed modelling of the large reservoirs of the RPV (the upper and lower plenums and the downcomer) were coupled with an in-house finite volume one-dimensional (1D) code in order to model the 451 coolant channels housing the nuclear fuel. Regarding the 1D code, suitable empirical correlations for taking into account the in-channel distributed (friction losses) and concentrated (spacer grids, inlet and outlet throttles) pressure losses were used. A local power distribution at each one of the coolant channels was also taken into account. The heat transfer between the coolant and the surrounding moderator was accurately calculated using a two-dimensional theoretical model. The implementation of subcooled boiling and condensation models in the 1D code along with the use of functions for representing the thermal and dynamic properties of the coolant and moderator (heavy water) allow to have estimations of the in-core steam generation under nominal flow conditions for a generic fission power distribution. The in-core mass flow distribution results for steady state nominal conditions are in agreement with the expected from design, thus getting a first assessment of the coupled 1/3D model. Results for nominal condition were compared with those obtained with a previous 1/3D single-phase model getting more realistic temperature patterns, also allowing visualize low values of void fraction inside the upper plenum. It must be mentioned that the current results were obtained by imposing prescribed fission power functions from literature. Therefore, results are showed with the aim of point out the potentiality of the developed model.

Keywords: PHWR, CFD, thermo-hydraulic, two-phase flow

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Authors: L. A. Ostrovsky, Yu. A. Stepanyants

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Effect of Earth rotation on nonlinear waves is a practically important and theoretically challenging problem of fluid mechanics and geophysics. Whereas the large-scale, geostrophic processes such as Rossby waves are a classical object of oceanic and atmospheric physics, rotation effects on mesoscale waves are not well studied. In particular, the Coriolis force can radically modify the behavior of nonlinear internal gravity waves in the ocean having spatial scales of 1-10 kilometers and time durations of few hours. In the last decade, such a non-trivial behavior was observed more than once. Similar effects are possible for magnetic sound in the ionosphere. Here we outline the main physical peculiarities in the behavior of nonlinear internal waves due to the rotation effect and present some results of our recent studies. The consideration is based on the fourth-order equation derived by one of the authors as a rotation-modified Korteweg–de Vries (rKdV) equation which includes two types of dispersion: one is responsible for the finiteness of depth as in the classical KdV equation; another is due to the Coriolis effect. This equation is, in general, non-integrable; moreover, under the conditions typical of oceanic waves (positive dispersion parameter), it does not allow solitary solutions at all. In the opposite case (negative dispersion) which is possible for, e.g., magnetic sound, solitary solutions do exist and can form complex bound states (multisoliton). Another non-trivial properties of nonlinear internal waves with rotation include, to name a few, the ‘terminal’ damping of the initial KdV soliton disappearing in a finite time due to radiation losses caused by Earth’s rotation, and eventual transformation of a KdV soliton into a wave packet (an envelope soliton). The new results to be discussed refer to the interaction of a soliton with a long background wave. It is shown, in particular, that in this case internal solitons can exist since the radiation losses are compensated by energy pumping from the background wave. Finally, the relevant oceanic observations of rotation effect on internal waves are briefly described.

Keywords: Earth rotation, internal waves, nonlinear waves, solitons

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Authors: I. A. Landa-Fernandez, I. Monje-Ramirez, M. T. Orta-Ledesma

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Every year plant-parasitic nematodes diminish the yield of high-value crops worldwide causing important economic losses. Currently, Meloidogyne enterolobii has increased its importance due to its high aggressiveness, increasing geographical distribution and host range. Root-knot nematodes inhabit the rhizosphere soil around plant roots. However, they can come into contact with irrigation water. Thus, plant-parasitic nematodes can be transported by water, as eggs or juveniles. Due to their high resistance, common water disinfection methods are not effective for inactivating these parasites. Ozone is the most effective disinfectant for microbial inactivation. The objective of this study is to demonstrate that ozone treatment is an alternative method control in irrigation water of the root-knot nematode M. enterolobii. It has been shown that ozonation is an effective treatment for the inactivation of protozoan cysts and oocysts (Giardia and Cryptosporidium) and for other species of the genus Meloidogyne (M. incognita), but not for the enterolobii specie. In this study, the strain of M. enterolobii was isolated from tomatoes roots. For the tests, eggs were used and were inoculated in water with similar characteristics of irrigation water. Subsequently, the disinfection process was carried out in an ozonation unit. The performance of the treatments was evaluated through the egg's viability by assessing its structure by optical microscopy. As a result of exposure to ozone, the viability of the nematode eggs was reduced practically in its entirety; with dissolved ozone levels in water close to the standard concentration (equal to 0.4 mgO₃/L), but with high contact times (greater than 4 min): 0.2 mgO₃/L for 15 minutes or 0.55 mgO₃/L for 10 minutes. Additionally, the effect of temperature, alkalinity and organic matter of the water was evaluated. Ozonation is effective and a promising alternative for the inactivation of nematodes in irrigation water, which could contribute to diminish the agricultural losses caused by these organisms.

Keywords: inactivation process, irrigation water treatment, ozonation, plant-parasite nematodes

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Authors: Nemat Sokhandan Bashir

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Threats from viruses to agricultural crops could be even larger than the losses caused by the other pathogens because, in many cases, the viral infection is latent but crucial from an epidemic point of view. Wild vegetation can be a source of many viruses that eventually find their destiny in crop plants. Although often asymptomatic in wild plants due to adaptation, they can potentially cause serious losses in crops. Therefore, exploring viruses in wild vegetation is very important. Recently, omics have been quite useful for exploring plant viruses from various plant sources, especially wild vegetation. For instance, we have discovered viruses such as Ambrossia asymptomatic virus I (AAV-1) through the application of metagenomics from Oklahoma Prairie Reserve. Accordingly, extracts from randomly-sampled plants are subjected to high speed and ultracentrifugation to separated virus-like particles (VLP), then nucleic acids in the form of DNA or RNA are extracted from such VLPs by treatment with phenol—chloroform and subsequent precipitation by ethanol. The nucleic acid preparations are separately treated with RNAse or DNAse in order to determine the genome component of VLPs. In the case of RNAs, the complementary cDNAs are synthesized before submitting to DNA sequencing. However, for VLPs with DNA contents, the procedure would be relatively straightforward without making cDNA. Because the length of the nucleic acid content of VPLs can be different, various strategies are employed to achieve sequencing. Techniques similar to so-called "chromosome walking" may be used to achieve sequences of long segments. When the nucleotide sequence data were obtained, they were subjected to BLAST analysis to determine the most related previously reported virus sequences. In one case, we determined that the novel virus was AAV-l because the sequence comparison and analysis revealed that the reads were the closest to the Indian citrus ringspot virus (ICRSV). AAV—l had an RNA genome with 7408 nucleotides in length and contained six open reading frames (ORFs). Based on phylogenies inferred from the replicase and coat protein ORFs of the virus, it was placed in the genus Mandarivirus.

Keywords: wild, plant, novel, metagenomics

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Authors: Ons Triki, Fathi Abid

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Along with the increase in the use of leasing contracts in corporate finance, multiple studies aim to model the credit risk of the lease in order to cover the losses of the lessor of the asset if the lessee goes bankrupt. In the current research paper, a convertible lease contract is elaborated in a continuous time stochastic universe aiming to ensure the financial stability of the firm and quickly recover the losses of the counterparties to the lease in case of default. This work examines the term structure of the lease rates taking into account the credit default risk and the capital structure of the firm. The interaction between the lessee's capital structure and the equilibrium lease rate has been assessed by applying the competitive lease market argument developed by Grenadier (1996) and the endogenous structural default model set forward by Leland and Toft (1996). The cumulative probability of default was calculated by referring to Leland and Toft (1996) and Yildirim and Huan (2006). Additionally, the link between lessee credit risk and lease rate was addressed so as to explore the impact of convertible lease financing on the term structure of the lease rate, the optimal leverage ratio, the cumulative default probability, and the optimal firm value by applying an endogenous conversion threshold. The numerical analysis is suggestive that the duration structure of lease rates increases with the increase in the degree of the market price of risk. The maximal value of the firm decreases with the effect of the optimal leverage ratio. The results are indicative that the cumulative probability of default increases with the maturity of the lease contract if the volatility of the asset service flows is significant. Introducing the convertible lease contract will increase the optimal value of the firm as a function of asset volatility for a high initial service flow level and a conversion ratio close to 1.

Keywords: convertible lease contract, lease rate, credit-risk, capital structure, default probability

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Authors: Lukasz Mierczak, Patrick Denke, Piotr Klimczyk, Stefan Siebert

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Due to the high complexity of the magnetization in electrical machines and influence of the manufacturing processes on the magnetic properties of their components, the assessment and prediction of hysteresis and eddy current losses has remained a challenge. In the design process of electric motors and generators, the power losses of stators and rotors are calculated based on the material supplier’s data from standard magnetic measurements. This type of data does not include the additional loss from non-sinusoidal multi-harmonic motor excitation nor the detrimental effects of residual stress remaining in the motor laminations after manufacturing processes, such as punching, housing shrink fitting and winding. Moreover, in production, considerable attention is given to the measurements of mechanical dimensions of stator and rotor cores, whereas verification of their magnetic properties is typically neglected, which can lead to inconsistent efficiency of assembled motors. Therefore, to enable a comprehensive characterization of motor materials and components, Brockhaus Measurements developed a range of in-line and offline measurement technologies for testing their magnetic properties under actual motor operating conditions. Multiple sets of experimental data were obtained to evaluate the influence of various factors, such as elevated temperature, applied and residual stress, and arbitrary magnetization on the magnetic properties of different grades of non-oriented steel. Measured power loss for tested samples and stator cores varied significantly, by more than 100%, comparing to standard measurement conditions. Quantitative effects of each of the applied measurement were analyzed. This research and applied Brockhaus measurement methodologies emphasized the requirement for advanced characterization of magnetic materials used in electric drives and automotive applications.

Keywords: magnetic materials, measurement technologies, permanent magnets, stator and rotor cores

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Authors: Gagik Ayvazyan, Levon Hakhoyan, Surik Khudaverdyan, Laura Lakhoyan

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Black Si (b-Si) is a nano-structured Si surface formed by a self-organized, maskless process with needle-like surfaces discernible by their black color. The combination of low reflectivity and the semi-conductive properties of Si found in b-Si make it a prime candidate for application in solar cells as an antireflection surface. However, surface recombination losses significantly reduce the efficiency of b-Si solar cells. Surface passivation using suitable dielectric films can minimize these losses. Nowadays some works have demonstrated that excellent passivation of b-Si nanostructures can be reached using Al₂O₃ films. However, the negative fixed charge present in Al₂O₃ films should provide good field effect passivation only for p- and p+-type Si surfaces. HfO2 thin films have not been practically tested for passivation of b-Si. HfO₂ could provide an alternative for n- and n+- type Si surface passivation since it has been shown to exhibit positive fixed charge. Using optical simulation by Finite-Difference Time Domain (FDTD) method, the possibility of b-Si passivation by HfO2 films has been analyzed. The FDTD modeling revealed that b-Si layers with HfO₂ films effectively suppress reflection in the wavelength range 400–1000 nm and across a wide range of incidence angles. The light-trapping performance primarily depends on geometry of the needles and film thickness. With the decrease of periodicity and increase of height of the needles, the reflectance decrease significantly, and the absorption increases significantly. Increase in thickness results in an even greater decrease in the calculated reflection coefficient of model structures and, consequently, to an improvement in the antireflection characteristics in the visible range. The excellent surface passivation and low reflectance results prove the potential of using the combination of the b-Si surface and the HfO₂ film for solar cells applications.

Keywords: antireflection, black silicon, HfO₂, passivation, simulation, solar cell

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Authors: Hafiza Javaria Ashraf, Asim Abbasi, Muhammad Hussnain Babar, Muhammad Sufyan

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Brevicoryne brassicae (Aphid) is not only the major biotic constraint of rapeseed crop but also transmits 20 different viral pathogens that cause diseases in crucifers. Aphids cause major losses to rapeseed by stunting growth and yield, with real damage being contamination of harvested heads. The misuse of pesticides has led to tremendous economic losses and hazards to human health and environmental pollution. Thus, newer approaches for pest control are continuously being sought. The naturally occurring, biologically active plant-based products seem to have a prominent role in the development of future commercial pesticides not only for increased productivity but their eco-friendly nature. The present experiment was carried out in Research Area of Ayub Agriculture Research Institute, Faisalabad to check the efficacy of different botanicals against rapeseed aphid. The tested botanicals were, neem seed extract, neem leaf extract, dathora seed extract, kaner leaf extract and aak leaf extract. Insecticide, advantage 20 EC served as the positive control in the experiment. Data was recorded before and after 1, 3 and 7 days of treatment application. The results of the experiment revealed that neem seed extract exhibited maximum mortality (48.42%) followed by dathora (45.54%) and kaner leaf extract (40.29%) after 7 days of treatment application. However minimum mortality i.e. 26.64% was observed in case of aak leaf extract. Advantage encountered maximum mortality i.e. 86.14%. All treatments caused maximum mortality after 7 days of treatment application. In case of pollinators maximum population reduction was observed in case of insecticide (74.29%) while minimum reduction was observed in neem leaf extract (11.57%). Hence it was concluded that unlike insecticides, plant based products can be a better option for regulating pests and conserving beneficial insect fauna.

Keywords: Aphid, mortality, plant based, pollinators

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Authors: Gusa Hall, Barrie Keeler, Achal Khanna

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Introduction: NICE guidelines have highlighted the consequences of IV fluid mismanagement. The main aim of this study was to audit fluid prescribing post laparotomies to identify if fluids were prescribed in accordance to NICE guidelines. Methodology: Retrospective database search of eight specific laparotomy procedures (colectomy right and left, Hartmann’s procedure, small bowel resection, perforated ulcer, abdominal perineal resection, anterior resection, pan proctocolectomy, subtotal colectomy) highlighted 29 laparotomies between April 2019 and May 2019. Two of 29 patients had secondary procedures during the same admission, n=27 (patients). Database case notes were reviewed for date of procedure, length of admission, fluid prescribed and amount, nasal gastric tube output, daily bloods results for electrolytes sodium and potassium and operational losses. Results: n=27 based on 27 identified patients between April 2019 – May 2019, 93% (25/27) received IV fluids, only 19% (5/27) received the correct IV fluids in accordance to NICE guidelines, 93% (25/27) who received IV fluids had the correct electrolytes levels (sodium & potassium), 100% (27/27) patients received blood tests (U&E’s) for correct electrolytes levels. 0% (0/27) no documentation on operational losses. IV fluids matched nasogastric tube output in 100% (3/3) of the number of patients that had a nasogastric tube in situ. Conclusion: A PubMed database literature review on barriers to safer IV prescribing highlighted educational interventions focused on prescriber knowledge rather than how to execute the prescribing task. This audit suggests IV fluids post laparotomies are not being prescribed consistently in accordance to NICE guidelines. Surgical management plans should be clearer on IV fluids and electrolytes requirements for the following 24 hours after the plan has been initiated. In addition, further teaching and training around IV prescribing is needed together with frequent surgical audits on IV fluid prescribing post-surgery to evaluate improvements.

Keywords: audit, IV Fluid prescribing, laparotomy, NICE guidelines

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Authors: Shatakshi Garg

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As the world continues to grapple with the COVID-19 pandemic, India, one of the most populous democratic federal developing nation, continues to report the highest active cases and deaths, as well as struggle to let its health infrastructure not succumb to the exponentially growing requirements of hospital beds, ventilators, oxygen to save thousands of lives daily at risk. In this context, the paper outlines the handling of the COVID-19 pandemic since it first hit India in January 2020 – the policy decisions taken by the Union and the State governments from the larger perspective of its federal structure. The Constitution of India adopted in 1950 enshrined the federal relations between the Union and the State governments by way of the constitutional division of revenue-raising and expenditure responsibilities. By way of the 72nd and 73rd Amendments in the Constitution, powers and functions were devolved further to the third tier, namely the local governments, with the intention of further strengthening the federal structure of the country. However, with time, several constitutional amendments have shifted the scales in favour of the union government. The paper briefly traces some of these major amendments as well as some policy decisions which made the federal relations asymmetrical. As a result, data on key fiscal parameters helps establish how the union government gained upper hand at the expense of weak state governments, reducing the local governments to mere constitutional bodies without adequate funds and fiscal autonomy to carry out the assigned functions. This quasi-federal structure of India with the union government amassing the majority of power in terms of ‘funds, functions and functionaries’ exposed the perils of weakening sub-national governments post COVID-19 pandemic. With a complex quasi-federal structure and a heterogeneous population of over 1.3 billion, the announcement of a sudden nationwide lockdown by the union government was followed by a plight of migrants struggling to reach homes safely in the absence of adequate arrangements for travel and safety-net made by the union government. With limited autonomy enjoyed by the states, they were mostly dictated by the union government on most aspects of handling the pandemic, including protocols for lockdown, re-opening post lockdown, and vaccination drive. The paper suggests that certain policy decisions like demonetization, the introduction of GST, etc., taken by the incumbent government since 2014 when they first came to power, have further weakened the states and local governments, which have amounted to catastrophic losses, both economic and human. The role of the executive, legislature and judiciary are explored to establish how all these three arms of the government have worked simultaneously to further weaken and expose the fault-lines of the federal structure of India, which has lent the nation incapacitated to handle this pandemic. The paper then suggests the urgency of re-looking at the federal structure of the country and undertaking measures that strengthen the sub-national governments and restore the federal spirit as was enshrined in the constitution to avoid mammoth human and economic losses from a pandemic of this sort.

Keywords: COVID-19 pandemic, India, federal structure, economic losses

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Authors: Yannay Casas-Ledon, Cinthya A. Andrade, Camila E. Salazar, Mauricio Aguayo

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The sustainable management of available natural resources is a crucial question for policy-makers, economists, and the research community. Among several, land constitutes one of the most critical resources, which is being intensively appropriated by human activities producing ecological stresses and reducing ecosystem services. In this context, net primary production (NPP) has been considered as a feasible proxy indicator for estimating the impacts of human interventions on land-uses intensity. Accordingly, the human appropriation of NPP (HANPP) was calculated for the south-central regions of Chile between 2007 and 2014. The HANPP was defined as the difference between the potential NPP of the naturally produced vegetation (NPP0, i.e., the vegetation that would exist without any human interferences) and the NPP remaining in the field after harvest (NPPeco), expressed in gC/m² yr. Other NPP flows taken into account in HANPP estimation were the harvested (NPPh) and the losses of NPP through land conversion (NPPluc). The ArcGIS 10.4 software was used for assessing the spatial and temporal HANPP changes. The differentiation of HANPP as % of NPP0 was estimated by each landcover type taken in 2007 and 2014 as the reference years. The spatial results depicted a negative impact on land use efficiency during 2007 and 2014, showing negative HANPP changes for the whole region. The harvest and biomass losses through land conversion components are the leading causes of loss of land-use efficiency. Furthermore, the study depicted higher HANPP in 2014 than in 2007, representing 50% of NPP0 for all landcover classes concerning 2007. This performance was mainly related to the higher volume of harvested biomass for agriculture. In consequence, the cropland depicted the high HANPP followed by plantation. This performance highlights the strong positive correlation between the economic activities developed into the region. This finding constitutes the base for a better understanding of the main driving force influencing biomass productivity and a powerful metric for supporting the sustainable management of land use.

Keywords: human appropriation, land-use changes, land-use impact, net primary productivity

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Authors: Sungin Jeong

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This paper presents a linear oscillating generator of cylindrical type for hybrid electric vehicle application. The focus of the study is the suggestion of the optimal model and the design rule of the cylindrical linear oscillating generator with permanent magnet in the back-iron translator. The cylindrical topology is achieved using equivalent magnetic circuit considering leakage elements as initial modeling. This topology with permanent magnet in the back-iron translator is described by number of phases and displacement of stroke. For more accurate analysis of an oscillating machine, it will be compared by moving just one-pole pitch forward and backward the thrust of single-phase system and three-phase system. Through the analysis and comparison, a single-phase system of cylindrical topology as the optimal topology is selected. Finally, the detailed design of the optimal topology takes the magnetic saturation effects into account by finite element analysis. Besides, the losses are examined to obtain more accurate results; copper loss in the conductors of machine windings, eddy-current loss of permanent magnet, and iron-loss of specific material of electrical steel. The considerations of thermal performances and mechanical robustness are essential, because they have an effect on the entire efficiency and the insulations of the machine due to the losses of the high temperature generated in each region of the generator. Besides electric machine with linear oscillating movement requires a support system that can resist dynamic forces and mechanical masses. As a result, the fatigue analysis of shaft is achieved by the kinetic equations. Also, the thermal characteristics are analyzed by the operating frequency in each region. The results of this study will give a very important design rule in the design of linear oscillating machines. It enables us to more accurate machine design and more accurate prediction of machine performances.

Keywords: equivalent magnetic circuit, finite element analysis, hybrid electric vehicle, linear oscillating generator

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Authors: Abdul Rehman, Bo Liu

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Axial flow turbines are commonly designed with high loads that generate strong secondary flows and result in high secondary losses. These losses contribute to almost 30% to 50% of the total losses. Non-axisymmetric endwall profiling is one of the passive control technique to reduce the secondary flow loss. In this paper, the non-axisymmetric endwall profile construction and optimization for the stator endwalls are presented to improve the efficiency of a high pressure turbine. The commercial code NUMECA Fine/ Design3D coupled with Fine/Turbo was used for the numerical investigation, design of experiments and the optimization. All the flow simulations were conducted by using steady RANS and Spalart-Allmaras as a turbulence model. The non-axisymmetric endwalls of stator hub and shroud were created by using the perturbation law based on Bezier Curves. Each cut having multiple control points was supposed to be created along the virtual streamlines in the blade channel. For the design of experiments, each sample was arbitrarily generated based on values automatically chosen for the control points defined during parameterization. The Optimization was achieved by using two algorithms i.e. the stochastic algorithm and gradient-based algorithm. For the stochastic algorithm, a genetic algorithm based on the artificial neural network was used as an optimization method in order to achieve the global optimum. The evaluation of the successive design iterations was performed using artificial neural network prior to the flow solver. For the second case, the conjugate gradient algorithm with a three dimensional CFD flow solver was used to systematically vary a free-form parameterization of the endwall. This method is efficient and less time to consume as it requires derivative information of the objective function. The objective function was to maximize the isentropic efficiency of the turbine by keeping the mass flow rate as constant. The performance was quantified by using a multi-objective function. Other than these two classifications of the optimization methods, there were four optimizations cases i.e. the hub only, the shroud only, and the combination of hub and shroud. For the fourth case, the shroud endwall was optimized by using the optimized hub endwall geometry. The hub optimization resulted in an increase in the efficiency due to more homogenous inlet conditions for the rotor. The adverse pressure gradient was reduced but the total pressure loss in the vicinity of the hub was increased. The shroud optimization resulted in an increase in efficiency, total pressure loss and entropy were reduced. The combination of hub and shroud did not show overwhelming results which were achieved for the individual cases of the hub and the shroud. This may be caused by fact that there were too many control variables. The fourth case of optimization showed the best result because optimized hub was used as an initial geometry to optimize the shroud. The efficiency was increased more than the individual cases of optimization with a mass flow rate equal to the baseline design of the turbine. The results of artificial neural network and conjugate gradient method were compared.

Keywords: artificial neural network, axial turbine, conjugate gradient method, non-axisymmetric endwall, optimization

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Authors: Mesbah Tarek, Kelaiaia Samia, Chiheb Sofien, Kelaiaia Mounia Samira, Labar Hocine

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Short circuit causes important damage in power systems. The aim of this paper is the investigation of the effect of short circuit at the AC side inverter in HVDC transmission line. The cutoff of HVDC transmission line implies important economic losses. In this paper it is proposed an efficient procedure which can protect and eliminate the fault quickly. The theoretical development and simulation are well detailed and illustrated.

Keywords: AC inverter, HVDC, short circuit, switcher gate, power system

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Authors: Vhahangwele Belemu, Isaac Busayo Oluwatayo

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Post-harvest losses pose a serious challenge to smallholder fruit crop farmers, especially in the rural communities of South Africa, affecting their economic livelihoods and food security. This study investigated the post-harvest handling practices and technologies harnessed by smallholder fruit crop farmers in the Vhembe district of Limpopo province, South Africa. Data were collected on a random sample of 224 smallholder fruit crop farmers selected from the four municipalities of the district using a multistage sampling technique. Analytical tools employed include descriptive statistics and the tobit regression model. A descriptive analysis of farmers’ socioeconomic characteristics showed that a sizeable number of these farmers are still in their active working age (mean = 52 years) with more males (63.8%) than their female (36.2%) counterparts. Respondents’ distribution by educational status revealed that only a few of these had no formal education (2.2%), with the majority having secondary education (48.7%). Results of data analysis further revealed that the prominent post-harvest technologies and handling practices harnessed by these farmers include using appropriate harvesting techniques (20.5%), selling at a reduced price (19.6%), transportation consideration (18.3%), cleaning and disinfecting (17.9%), sorting and grading (16.5%), manual cleaning (15.6%) and packaging technique (11.6%) among others. The result of the Tobit regression analysis conducted to examine the determinants of post-harvest technologies and handling practices harnessed showed that age, educational status of respondents, awareness of technology/handling practices, farm size, access to credit, extension contact, and membership of association were the significant factors. The study suggests enhanced awareness creation, access to credit facility and improved access to market as important factors to consider by relevant stakeholders to assist smallholder fruit crop farmers in the study area.

Keywords: fruit crop farmers, handling practices, post harvest losses, smallholder, Vhembe District, South Africa

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Authors: Muhammad Arzim Naim, Saiful Azhar Rosly, Mohamad Sahari Nordin

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The objective of this study is to investigate the factors affecting the rise of Shariah non-compliance risk that can bring Islamic banks to succumb to monetary loss. Prior literatures have never analyzed such risk in details despite lots of it arguing on the validity of some Shariah compliance products. The Shariah non-compliance risk in this context is looking to the potentially failure of the facility to stand from the court test say that if the banks bring it to the court for compensation from the defaulted clients. The risk may also arise if the customers refuse to make the financing payments on the grounds of the validity of the contracts, for example, when relinquishing critical requirement of Islamic contract such as ownership, the risk that may lead the banks to suffer loss when the customer invalidate the contract through the court. The impact of Shariah non-compliance risk to Islamic banks is similar to that of legal risks faced by the conventional banks. Both resulted into monetary losses to the banks respectively. In conventional banking environment, losses can be in the forms of summons paid to the customers if they won the case. In banking environment, this normally can be in very huge amount. However, it is right to mention that for Islamic banks, the subsequent impact to them can be rigorously big because it will affect their reputation. If the customers do not perceive them to be Shariah compliant, they will take their money and bank it in other places. This paper provides new insights of risks faced by credit intensive Islamic banks by providing a new extension of knowledge with regards to the Shariah non-compliance risk by identifying its individual components that directly affecting the risk together with empirical evidences. Not limited to the Islamic banking fraternities, the regulators and policy makers should be able to use findings in this paper to evaluate the components of the Shariah non-compliance risk and make the necessary actions. The paper is written based on Malaysia’s Islamic banking practices which may not directly related to other jurisdictions. Even though the focuses of this study is directly towards to the Bay Bithaman Ajil or popularly known as BBA (i.e. sale with deferred payments) financing modality, the result from this study may be applicable to other Islamic financing vehicles.

Keywords: Islamic banking, Islamic finance, Shariah Non-compliance risk, Bay Bithaman Ajil (BBA), principal axis factoring

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Authors: Da Kuang

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Resilience is a hotly debated topic in many research fields (e.g., engineering, ecology, society, psychology). In flood management studies, we are experiencing the paradigm shift from flood resistance to flood resilience. Flood resilience refers to tolerate flooding through adaptation or transformation. It is increasingly argued that our city as a social-ecological system holds the ability to learn from experience and adapt to flood rather than simply resist it. This research aims to investigate what kinds of adaptation knowledge the frequently flooded village learned from past experience and its advantages and limitations in coping with floods. The study area – Xinnongcun village, located in the west of Wuhan city, is a linear village and continuously suffered from both flash flood and drainage flood during the past 30 years. We have a field trip to the site in June 2017 and conducted semi-structured interviews with local residents. Our research summarizes two types of adaptation knowledge that people learned from the past floods. Firstly, at the village scale, it has formed a collective urban form which could help people live during both flood and dry season. All houses and front yards were elevated about 2m higher than the road. All the front yards in the village are linked and there is no barrier. During flooding time, people walk to neighbors through houses yards and boat to outside village on the lower road. Secondly, at individual scale, local people learned tacit knowledge of preparedness and emergency response to flood. Regarding the advantages and limitations, the adaptation knowledge could effectively help people to live with flood and reduce the chances of getting injuries. However, it cannot reduce local farmers’ losses on their agricultural land. After flood, it is impossible for local people to recover to the pre-disaster state as flood emerges during June and July will result in no harvest. Therefore, we argue that learning from past flood experience could increase people’s adaptive capacity. However, once the adaptive capacity cannot reduce people’s losses, it requires a transformation to a better regime.

Keywords: adaptation, flood resilience, tacit knowledge, transformation

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Authors: Francesco Pandolfi, Georgios Baltzopoulos, Iunio Iervolino

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The impact of extreme winds on industrial assets and the built environment is gaining increasing attention from stakeholders, including the corporate insurance industry. This has led to a progressively more in-depth study of building vulnerability and fragility to wind. Wind vulnerability models are used in probabilistic risk assessment to relate a loss metric to an intensity measure of the natural event, usually a gust or a mean wind speed. In fact, vulnerability models can be integrated with the wind hazard, which consists of associating a probability to each intensity level in a time interval (e.g., by means of return periods) to provide an assessment of future losses due to extreme wind. This has also given impulse to the world- and regional-scale wind hazard studies.Another approach often adopted for the probabilistic description of building vulnerability to the wind is the use of fragility functions, which provide the conditional probability that selected building components will exceed certain damage states, given wind intensity. In fact, in wind engineering literature, it is more common to find structural system- or component-level fragility functions rather than wind vulnerability models for an entire building. Loss assessment based on component fragilities requires some logical combination rules that define the building’s damage state given the damage state of each component and the availability of a consequence model that provides the losses associated with each damage state. When risk calculations are based on numerical simulation of a structure’s behavior during extreme wind scenarios, the interaction of component fragilities is intertwined with the computational procedure. However, simulation-based approaches are usually computationally demanding and case-specific. In this context, the present work introduces the ExtReMe wind risk assESsment prototype Software, ERMESS, which is being developed at the University of Naples Federico II. ERMESS is a wind risk assessment tool for insurance applications to industrial facilities, collecting a wide assortment of available wind vulnerability models and fragility functions to facilitate their incorporation into risk calculations based on in-built or user-defined wind hazard data. This software implements an alternative method for building-specific risk assessment based on existing component-level fragility functions and on a number of simplifying assumptions for their interactions. The applicability of this alternative procedure is explored by means of an illustrative proof-of-concept example, which considers four main building components, namely: the roof covering, roof structure, envelope wall and envelope openings. The application shows that, despite the simplifying assumptions, the procedure can yield risk evaluations that are comparable to those obtained via more rigorous building-level simulation-based methods, at least in the considered example. The advantage of this approach is shown to lie in the fact that a database of building component fragility curves can be put to use for the development of new wind vulnerability models to cover building typologies not yet adequately covered by existing works and whose rigorous development is usually beyond the budget of portfolio-related industrial applications.

Keywords: component wind fragility, probabilistic risk assessment, vulnerability model, wind-induced losses

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Authors: Dorota Zielińska, Monika Trząskowska, Anna Łepecka, Katarzyna Neffe-Skocińska, Beata Bilska, Marzena Tomaszewska, Danuta Kołożyn-Krajewska

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Minimum durability date (MDD) labeled food is known to have a long shelf life. A properly stored or transported food retains its physical, chemical, microbiological, and sensory properties up to MDD. The aim of the study was to assess the sensory quality and microbiological safety of selected thermally processed products,i.e., mayonnaise, jam, and canned tuna within and after MDD. The scope of the study was to determine the markers of microbiological quality, i.e., the total viable count (TVC), the Enterobacteriaceae count and the total yeast and mold (TYMC) count on the last day of MDD and after 1 and 3 months of storage, after the MDD expired. In addition, the presence of Salmonella and Listeria monocytogenes was examined on the last day of MDD. The sensory quality of products was assessed by quantitative descriptive analysis (QDA), the intensity of differentiators (quality features), and overall quality were defined and determined. It was found that during three months storage of tested food products, after the MDD expired, the microbiological quality slightly decreased, however, regardless of the tested sample, TVC was at the level of <3 log cfu/g, similarly, the Enterobacretiaceae, what indicates the good microbiological quality of the tested foods. The TYMC increased during storage but did not exceed 2 logs cfu/g of product. Salmonella and Listeria monocytogenes were not found in any of the tested food samples. The sensory quality of mayonnaise negatively changed during storage. After three months from the expiry of MDD, a decrease in the "fat" and "egg" taste and aroma intensity, as well as the "density" were found. The "sour" taste intensity of blueberry jam after three months of storage was slightly higher, compared to the jam tested on the last day of MDD, without affecting the overall quality. In the case of tuna samples, an increase in the "fishy" taste and aroma intensity was observed during storage, and the overall quality did not change. Tested thermally processed products (mayonnaise, jam, and canned tuna) were characterized by good microbiological and sensory quality on the last day of MDD, as well as after three months of storage under conditions recommended by the producer. These findings indicate the possibility of reducing food losses by extending or completely abolishing the MDD of selected thermal processed food products.

Keywords: food wastes, food quality and safety, mayonnaise, jam, tuna

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Authors: Pasan Dunuwila, V. H. L. Rodrigo, Naohiro Goto

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Sri Lanka is one the largest natural rubber (NR) producers of the world, where the NR industry is a major foreign exchange earner. Among the locally manufactured NR products, concentrated latex (CL) and ribbed smoked sheets (RSS) hold a significant position. Furthermore, these products become the foundation for many products utilized by the people all over the world (e.g. gloves, condoms, tires, etc.). Processing of CL and RSS costs a significant amount of material, energy, and workforce. With this background, both manufacturing lines have immensely challenged by waste, low productivity, lack of cost efficiency, rising cost of production, and many environmental issues. To face the above challenges, the adaptation of sustainable manufacturing measures that use less energy, water, materials, and produce less waste is imperative. However, these sectors lack comprehensive studies that shed light on such measures and thoroughly discuss their improvement potentials from both environmental and economic points of view. Therefore, based on a study of three CL and three RSS mills in Sri Lanka, this study deploys sustainable manufacturing techniques and tools to uncover the underlying potentials to improve performances in CL and RSS processing sectors. This study is comprised of three steps: 1. quantification of average material waste, economic losses, and greenhouse gas (GHG) emissions via material flow analysis (MFA), material flow cost accounting (MFCA), and life cycle assessment (LCA) in each manufacturing process, 2. identification of improvement options with the help of Pareto and What-if analyses, field interviews, and the existing literature; and 3. validation of the identified improvement options via the re-execution of MFA, MFCA, and LCA. With the help of this methodology, the economic and environmental hotspots, and the degrees of improvement in both systems could be identified. Results highlighted that each process could be improved to have less waste, monetary losses, manufacturing costs, and GHG emissions. Conclusively, study`s methodology and findings are believed to be beneficial for assuring the sustainable growth not only in Sri Lankan NR processing sector itself but also in NR or any other industry rooted in other developing countries.

Keywords: concentrated latex, natural rubber, ribbed smoked sheets, Sri Lanka

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Authors: Liaqat Ali, Furqan Ahmad

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The heat losses should be controlled during the high temperature processes from energy conservation point of view. For this purpose, refractories with low thermal conductivity, high porosity and good mechanical strength along with low price are desirable. In this work, various combinations of naturally occurring, locally available, cheap raw materials, namely, clay, rice husk and saw dust were used. Locally produced insulating firebricks (IFBs) cannot be used at higher than a few hundred °C and possess low strength as well. Various process parameters were studied and the refractories with desirable properties were produced, which can be used up to 1200 °C.

Keywords: firebricks, mechanical strength, thermal conductivity, refractory bricks

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Authors: Gulshan Mammadova

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This paper presents the results of studying the surface microrelief in 2D and 3D models and analyzing the spectroscopy of a three-junction TlInSe₂ crystal. Analysis of the results obtained showed that with a change in the composition of the TlInSe₂ crystal, sharp changes occur in the microrelief of its surface. An X-ray optical diffraction analysis of the TlInSe₂ crystal was experimentally carried out. Based on ellipsometric data, optical functions were determined - the real and imaginary parts of the dielectric permittivity of crystals, the coefficients of optical absorption and reflection, the dependence of energy losses and electric field power on the effective density, the spectral dependences of the real (σᵣ) and imaginary (σᵢ) parts, optical electrical conductivity were experimentally studied. The fluorescence spectra of the ternary compound TlInSe₂ were isolated and analyzed when excited by light with a wavelength of 532 nm. X-ray studies of TlInSe₂ showed that this phase crystallizes into tetragonal systems. Ellipsometric measurements showed that the real (ε₁) and imaginary (ε₂) parts of the dielectric constant are components of the dielectric constant tensor of the uniaxial joints under consideration and do not depend on the angle. Analysis of the dependence of the real and imaginary parts of the refractive index of the TlInSe₂ crystal on photon energy showed that the nature of the change in the real and imaginary parts of the dielectric constant does not differ significantly. When analyzing the spectral dependences of the real (σr) and imaginary (σi) parts of the optical electrical conductivity, it was noticed that the real part of the optical electrical conductivity increases exponentially in the energy range 0.894-3.505 eV. In the energy range of 0.654-2.91 eV, the imaginary part of the optical electrical conductivity increases linearly, reaches a maximum value, and decreases at an energy of 2.91 eV. At 3.6 eV, an inversion of the imaginary part of the optical electrical conductivity of the TlInSe₂ compound is observed. From the graphs of the effective power density versus electric field energy losses, it is known that the effective power density increases significantly in the energy range of 0.805–3.52 eV. The fluorescence spectrum of the ternary compound TlInSe₂ upon excitation with light with a wavelength of 532 nm has been studied and it has been established that this phase has luminescent properties.

Keywords: optical properties, dielectric permittivity, real and imaginary dielectric permittivity, optical electrical conductivity

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Authors: Omid Pourabdollah, Mohsen Misaghian

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Overtopping is known as one the most important reasons for the failure of earth dams. In some cases, it has resulted in heavy damages and losses. Therefore, enhancing the safety of earth dams against overtopping has received much attention in the past four decades. In this paper, at first, the overtopping phenomena and its destructive consequences will be introduced. Then, overtopping failure mechanism of embankments will be described. Finally, different types of protection systems for stabilization of earth dams against overtopping will be presented. These include timber cribs, riprap and gabions, reinforced earth, roller compacted concrete, and the precast concrete blocks.

Keywords: embankment dam, overtopping, roller compacted concrete, wedge concrete block

Procedia PDF Downloads 119

Authors: Ridwaan N. Milase, Leonardo J. Van Zyl, Marla Trindade

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American foulbrood (AFB) is the world’s most devastating honeybee disease that has drastically reduced the population of Apis mellifera capensis since 2009. The outbreak has jeopardized the South African bee keeping industry as well as the agricultural sector dependent on honeybees for honey production and pollination, leading to significant economic losses. AFB is caused by Paenibacillus larvae, a spore-forming, Gram positive facultative anaerobic and flagellated bacterium. The use of antibiotics within beehives has selected for resistant strains of P. larvae, while the current practice of burning spore contaminated beehives and equipment contributes to the economic losses in the honeybee-keeping industry. Therefore, phage therapy is proposed as a promising alternative to combat P. larvae strains affecting A. mellifera capensis. The genomes of two P. larvae strains isolated from infected combs in the Western Cape have been sequenced and annotated using bioinformatics tools. Genome analyses has revealed that these P. larvae strains are lysogens to more than 6 different prophages and possess different type of clustered regularly interspaced short palindromic repeat (CRISPRs) regions per strain. Active prophages from one of the two P. larvae strains were detected and identified using PCR. Electron microscopy was used to determine the family of the identified active prophages. Lytic bacteriophages that specifically target the two P. larvae strains were purified from sewage wastewater, beehive materials, and soil samples to investigate their potential development as anti-P. larvae agents. Another alternative treatment being investigated is the development of a prophage endolysin cocktail. Endolysin genes of the prophages have been targeted, cloned and expressed in Escherichia coli. The heterologously expressed endolysins have been purified and are currently being assessed for their lytic activity against P. larvae strains and other commensal microorganisms that compose the honeybee larvae microbiota. The study has shown that phage therapy and endolysins have a great potential as alternative control methods for AFB disease affecting A. mellifera capensis.

Keywords: American foulbrood, bacteriophage, honeybee, Paenibacillus larvae

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Authors: G. V. Siva Krishna Rao, B. Srinivasa Rao

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The main aim of the paper is to implement a technique using distributed generation in distribution systems to reduce the distribution system losses and to improve voltage profiles. The fuzzy logic technique is used to select the proper location of DG and an analytical method is proposed to calculate the size of DG unit at any power factor. The optimal sizes of DG units are compared with optimal sizes obtained using the genetic algorithm. The suggested method is programmed under Matlab software and is tested on IEEE 33 bus system and the results are presented.

Keywords: DG Units, sizing of DG units, analytical methods, optimum size

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Authors: Larry O. Awo, George N. Duru

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There are growing public and mental health concerns over the availability of gambling platforms and shops in Nigeria and the high level of youth involvement in gambling. Early theorizing maintained that gambling involvement was driven by a quest for resource gains. However, evidence shows that the economic model of gambling tends to explain the involvement of the gambling business owners (sport lottery operators: SLOs) as most gamblers lose more than they win. This loss, according to the law of effect, ought to discourage decisions to gamble. However, the quest to recover losses has often initiated prolonged gambling sessions. Therefore, the need to investigate mental contemplations (such as counterfactual reasoning (upward versus downward) of what “would, should, or could” have been, and feeling of the illusion of control; IOC) over gambling outcomes as risk or protective factors in gambling decisions became pertinent. The present study sought to understand the differential contributions and conditional effects of upward versus downward counterfactual reasoning as pathways through which the association between IOC and gambling decisions of Nigerian youths (N = 120, mean age = 18.05, SD = 3.81) could be explained. The study adopted a randomized group design, and data were obtained by means of stimulus material (the Gambling Episode; GE) and self-report measures of IOC and Gambling Decision. One-way analysis of variance (ANOVA) result showed that participants in the upward counterfactual reasoning group (M = 22.08) differed from their colleagues in the downward counterfactual reasoning group (M = 17.33) on the decision to gamble, and this difference was significant [F(1,112) = 23, P < .01]. HAYES PROCESS macro moderation analysis results showed that 1) IOC and upward counterfactual reasoning were positively associated with the decision to gamble (B = 14.21, t = 6.10, p < .01 and B = 7.22, t = 2.07, p <.05, respectively), 2) downward counterfactual reasoning was negatively associated with the decision to gamble more to recover losses (B = 10.03, t = 3.21, p < .01), 3) upward counterfactual reasoning did not moderate the association between IOC and gambling decision (p > .05), and 4) downward counterfactual reasoning negatively moderated the association between IOC and gambling decision (B = 07, t = 2.18, p < .05) such that the association was strong at the low level of downward counterfactual, but wane at high levels of downward counterfactual reasoning. The implication of these findings is that IOC and upward counterfactual reasoning were risk factors and promoted gambling behavior, while downward counterfactual reasoning protects individuals from gambling activities. Thus, it is concluded that downward counterfactual reasoning strategies should be included in gambling therapy and treatment packages as it could diminish feelings of both IOC and negative feelings of missed positive outcomes and the urge to gamble.

Keywords: counterfactual reasoning, gambling cognition, gambling decision, Nigeria, youths

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Authors: German Osma, Gabriel Ordonez

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The production of metal-rubber spares for vehicles is a sequential process that consists in the transformation of raw material through cutting activities and chemical and thermal treatments, which demand electricity and fossil fuels. The energy efficiency analysis for these cases is mostly focused on studying of each machine or production step, but is not common to study of the quality of the production process achieves from aggregated value viewpoint, which can be used as a quality measurement for determining of impact on the environment. In this paper, the theory of exergetic cost is used for determining of aggregated exergy to three metal-rubber spares, from an exergy analysis and thermoeconomic analysis. The manufacturing processing of these spares is based into batch production technique, and therefore is proposed the use of this theory for discontinuous flows from of single models of workstations; subsequently, the complete exergy model of each product is built using flowcharts. These models are a representation of exergy flows between components into the machines according to electrical, mechanical and/or thermal expressions; they determine the demanded exergy to produce the effective transformation in raw materials (aggregated exergy value), the exergy losses caused by equipment and irreversibilities. The energy resources of manufacturing process are electricity and natural gas. The workstations considered are lathes, punching presses, cutters, zinc machine, chemical treatment tanks, hydraulic vulcanizing presses and rubber mixer. The thermoeconomic analysis was done by workstation and by spare; first of them describes the operation of the components of each machine and where the exergy losses are; while the second of them estimates the exergy-aggregated value for finished product and wasted feedstock. Results indicate that exergy efficiency of a mechanical workstation is between 10% and 60% while this value in the thermal workstations is less than 5%; also that each effective exergy-aggregated value is one-thirtieth of total exergy required for operation of manufacturing process, which amounts approximately to 2 MJ. These troubles are caused mainly by technical limitations of machines, oversizing of metal feedstock that demands more mechanical transformation work, and low thermal insulation of chemical treatment tanks and hydraulic vulcanizing presses. From established information, in this case, it is possible to appreciate the usefulness of theory of exergetic cost for analyzing of aggregated value in manufacturing processes.

Keywords: exergy-aggregated value, exergy efficiency, thermoeconomics, exergy modeling

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Authors: Aktar-Uz-Zaman, M. Tuhina-Khatun, Mohamed Hanafi Musa

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Three rust diseases: leaf (brown) rust caused by Puccinia triticina Eriks, stripe (yellow) rust caused by Puccinia striiformis West, and stem (black) rust caused by Puccinia graminis f. sp. tritici are economically important diseases of wheat in world wide. Yield loss due to leaf rust is 40% in susceptible cultivars. Yield losses caused by the stem rust pathogens in the mid of 20 century reached 20-30% in Eastern and Central Europe and the most virulent stem rust race Ug99 emerged first in Uganda and after that in Kenya, Ethiopia, Yemen, in the Middle East and South Asia. Yield losses were estimated up to 100%, whereas, up to 80% have been reported in Kenya during 1999. In case of stripe rust, severity level has been recorded 60% - 70% as compared to 100% severity of susceptible check in disease screening nurseries in Kenya. Improvement of resistant varieties or cultivars is the sustainable, economical and environmentally friendly approaches for increasing the global wheat production to suppress the rust diseases. More than 68 leaf rust, 49 stripe rust and 53 stem rust resistance genes have been identified in the global wheat cultivars or varieties using different molecular breeding approaches. Among these, Lr1, Lr9, Lr10, Lr19, Lr21, Lr24, Lr25, Lr28, Lr29, Lr34, Lr35, Lr37, Lr39, Lr47, Lr51, Lr3bg, Lr18, Lr40, Lr46, and Lr50 leaf rust resistance genes have been identified by using molecular, enzymatic and microsatellite markers from African, Asian, European cultivars of hexaploid wheat (Triticum aestivum), durum wheat and diploid wheat species. These genes are located on 20, of the 21 chromosomes of hexaploid wheat. Similarly, Sr1, Sr2, Sr24, and Sr3, Sr31 stem rust resistance genes have been recognized from wheat cultivars of Pakistan, India, Kenya, and Uganda etc. A race of P. striiformis (stripe rust) Yr9, Yr18, and Yr29 was first observed in East Africa, Italy, Pakistan and India wheat cultivars. These stripe rust resistance genes are located on chromosomes 1BL, 4BL, 6AL, 3BS and 6BL in bread wheat cultivars. All these identified resistant genes could be used for notable improvement of susceptible wheat cultivars in the future.

Keywords: hexaploid wheat, resistance genes, rust disease, triticum aestivum

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Authors: Georgios A. Fragkiadakis, Antonia Psaroudaki, Theodora Mouratidou, Eirini Sfakianaki

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Research: Within the project "Actions for the optimal utilization of the potential of carob in the Region of Crete" which is financed-supervised by the Region, with collaboration of Crete University and Hellenic Mediterranean University, a SWOT (strengths, weaknesses, opportunities, threats) survey was carried out, to evaluate the prospects of carob in human nutrition, in Crete. Results and conclusions: 1). Strengths: There exists a local production of carob for human consumption, based on international reports, and local-product reports. The data on products in the market (over 100 brands of carob food), indicates a sufficiency of carob materials offered in Crete. The variety of carob food products retailed in Crete indicates a strong demand-production-consumption trend. There is a stable number (core) of businesses that invest significantly (Creta carob, Cretan mills, etc.). The great majority of the relevant food stores (bakery, confectionary etc.) do offer carob products. The presence of carob products produced in Crete is strong on the internet (over 20 main professionally designed websites). The promotion of the carob food-products is based on their variety and on a few historical elements connected with the Cretan diet. 2). Weaknesses: The international prices for carob seed affect the sector; the seed had an international price of €20 per kg in 2021-22 and fell to €8 in 2022, causing losses to carob traders. The local producers do not sort the carobs they deliver for processing, causing 30-40% losses of the product in the industry. The occasional high price triggers the collection of degraded raw material; large losses may emerge due to the action of insects. There are many carob trees whose fruits are not collected, e.g. in Apokoronas, Chania. The nutritional and commercial value of the wild carob fruits is very low. Carob trees-production is recorded by Greek statistical services as "other cultures" in combination with prickly pear i.e., creating difficulties in retrieving data. The percentage of carob used for human nutrition, in contrast to animal feeding, is not known. The exact imports of carob are not closely monitored. We have no data on the recycling of carob by-products in Crete. 3). Opportunities: The development of a culture of respect for carob trade may improve professional relations in the sector. Monitoring carob market and connecting production with retailing-industry needs may allow better market-stability. Raw material evaluation procedures may be implemented to maintain carob value-chain. The state agricultural services may be further involved in carob-health protection. The education of farmers on carob cultivation/management, can improve the quality of the product. The selection of local productive varieties, may improve the sustainability of the culture. Connecting the consumption of carob with health-food products, may create added value in the sector. The presence and extent of wild carob threes in Crete, represents, potentially, a target for grafting. 4). Threats: The annual fluctuation of carob yield challenges the programming of local food industry activities. Carob is a forest species also - there is danger of wrong classification of crops as forest areas, where land ownership is not clear.

Keywords: human nutrition, carob food, SWOT analysis, crete, greece

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