Search results for: sink limitation

Authors: Zaki Abiza, Miguel Chavez, David M. Holman, Ruddy Brionnaud

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In this paper, the prediction of the aerodynamic behavior of the flow around a Finned Projectile will be validated using a Computational Fluid Dynamics (CFD) solution, XFlow, based on the Lattice-Boltzmann Method (LBM). XFlow is an innovative CFD software developed by Next Limit Dynamics. It is based on a state-of-the-art Lattice-Boltzmann Method which uses a proprietary particle-based kinetic solver and a LES turbulent model coupled with the generalized law of the wall (WMLES). The Lattice-Boltzmann method discretizes the continuous Boltzmann equation, a transport equation for the particle probability distribution function. From the Boltzmann transport equation, and by means of the Chapman-Enskog expansion, the compressible Navier-Stokes equations can be recovered. However to simulate compressible flows, this method has a Mach number limitation because of the lattice discretization. Thanks to this flexible particle-based approach the traditional meshing process is avoided, the discretization stage is strongly accelerated reducing engineering costs, and computations on complex geometries are affordable in a straightforward way. The projectile that will be used in this work is the Army-Navy Basic Finned Missile (ANF) with a caliber of 0.03 m. The analysis will consist in varying the Mach number from M=0.5 comparing the axial force coefficient, normal force slope coefficient and the pitch moment slope coefficient of the Finned Projectile obtained by XFlow with the experimental data. The slope coefficients will be obtained using finite difference techniques in the linear range of the polar curve. The aim of such an analysis is to find out the limiting Mach number value starting from which the effects of high fluid compressibility (related to transonic flow regime) lead the XFlow simulations to differ from the experimental results. This will allow identifying the critical Mach number which limits the validity of the isothermal formulation of XFlow and beyond which a fully compressible solver implementing a coupled momentum-energy equations would be required.

Keywords: CFD, computational fluid dynamics, drag, finned projectile, lattice-boltzmann method, LBM, lift, mach, pitch

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Authors: Joana Gato, Ahmed Abotabekh, Panayoti Bachkangi

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Introduction: Oestrogen is an essential gonadal hormone that plays a vital role in the reproductive system of women1. The average age of menopause in the UK is 512. Women who go through premature menopause should be offered Hormone replacement therapy (HRT). Similarly, women who undergo surgical menopause should be offered HRT, unless contraindicated, depending on the indication of their surgery2,3. Aim: To assess if the patients in our department are counselled regarding HRT after surgical treatment and if HRT was prescribed. Methodology: A retrospective audit in a busy district hospital, examining all the patients who had a hysterectomy. The audit examined if HRT was discussed pre-operatively, prescribed on discharge and if a follow up was arranged. For women with contraindication to HRT, the audit assessed if the reasons were discussed pre-operatively and communicated to the Inclusion criteria: woman having a total or subtotal hysterectomy, with or without bilateral salpingo-ophorectomy (BSO), between April and September 2022. Exclusion criteria: woman having a vaginal hysterectomy. Results: 40 patients in total had hysterectomy; 27 (68%) were under the age of 51. 15 out of 27 patients bad BSO. 9 women were prescribed HRT, but 8 were offered HRT immediately, and 1 of them were offered a follow up. Of women who underwent surgical menopause, 7 were not given any HRT. The HRT choice was diverse, however, the majority was prescribed oral HRT. 40% of women undergoing surgical menopause did not have a discussion about HRT prior to their surgery. In postmenopausal women (n=13; 33%), still two were given HRT for preexisting menopausal symptoms. Discussion: Only 59% of the pre-menopausal patients had oophorectomy, therefore undergoing surgical menopause. Of these, 44% were not given any HRT, and 40% had no discussion about HRT prior to surgery. Interestingly, the majority of these women have no obvious contraindication to HRT. The choice of HRT was diverse, but the majority was commenced on oral HRT. Our unit is still working towards meeting all the NICE guidance standards of offering HRT and information prior to surgery to women planning to undergo surgical menopause. Conclusion: Starting HRT at the onset of menopause has been shown to improve quality of life and reduce the risk of cardiovascular disease and osteoporotic fractures4. Our unit still has scope for improvement to comply with the current NICE guidance. All pre-menopausal women undergoing surgical menopause should have a discussion regarding HRT prior to surgery and be offered it if there are no contraindications. This discussion should be clearly documented in the notes. At the time of this report, some of the patients have not yet had a follow up, which we recognize as a limitation to our audit.

Keywords: hormone replacement therapy, menopause, premature ovarian insufficiency, surgical management

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Authors: Takashi Yamaguchi, Ichio Asanuma, Jong G. Park, Kenneth J. Mackin, John Mittleman

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In this paper, vessel detection using the artificial neural network is proposed in order to automatically construct the vessel detection model from the satellite imagery of day/night band (DNB) in visible infrared in the products of Imaging Radiometer Suite (VIIRS) on Suomi National Polar-orbiting Partnership (Suomi-NPP).The goal of our research is the establishment of vessel detection method using the satellite imagery of DNB in order to monitor the change of vessel activity over the wide region. The temporal vessel monitoring is very important to detect the events and understand the circumstances within the maritime environment. For the vessel locating and detection techniques, Automatic Identification System (AIS) and remote sensing using Synthetic aperture radar (SAR) imagery have been researched. However, each data has some lack of information due to uncertain operation or limitation of continuous observation. Therefore, the fusion of effective data and methods is important to monitor the maritime environment for the future. DNB is one of the effective data to detect the small vessels such as fishery ships that is difficult to observe in AIS. DNB is the satellite sensor data of VIIRS on Suomi-NPP. In contrast to SAR images, DNB images are moderate resolution and gave influence to the cloud but can observe the same regions in each day. DNB sensor can observe the lights produced from various artifact such as vehicles and buildings in the night and can detect the small vessels from the fishing light on the open water. However, the modeling of vessel detection using DNB is very difficult since complex atmosphere and lunar condition should be considered due to the strong influence of lunar reflection from cloud on DNB. Therefore, artificial neural network was applied to learn the vessel detection model. For the feature of vessel detection, Brightness Temperature at the 3.7 μm (BT3.7) was additionally used because BT3.7 can be used for the parameter of atmospheric conditions.

Keywords: artificial neural network, day/night band, remote sensing, Suomi National Polar-orbiting Partnership, vessel detection, Visible Infrared Imaging Radiometer Suite

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Authors: Mariia Khramova, Sergio Martinez, Duc Nguyen

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Modern electronic devices, particularly smartphones, are characterised by extremely high environmental footprint and short product lifecycle. Every year manufacturers release new models with even more superior performance, which pushes the customers towards new purchases. As a result, millions of devices are being accumulated in the urban mine. To tackle these challenges the concept of circular economy has been introduced to promote repair, reuse and recycle of electronics. In this case, electronic devices, that previously ended up in landfills or households, are getting the second life, therefore, reducing the demand for new raw materials. Smartphone reuse is gradually gaining wider adoption partly due to the price increase of flagship models, consequently, boosting circular economy implementation. However, along with reuse of communication device, circular economy approach needs to ensure the data of the previous user have not been 'reused' together with a device. This is especially important since modern smartphones are comparable with computers in terms of performance and amount of data stored. These data vary from pictures, videos, call logs to social security numbers, passport and credit card details, from personal information to corporate confidential data. To assess how well the data privacy requirements are followed on smartphones second-hand market, a sample of 100 Android smartphones has been purchased from IT Asset Disposition (ITAD) facilities responsible for data erasure and resell. Although devices should not have stored any user data by the time they leave ITAD, it has been possible to retrieve the data from 19% of the sample. Applied techniques varied from manual device inspection to sophisticated equipment and tools. These findings indicate significant barrier in implementation of circular economy and a limitation of smartphone reuse. Therefore, in order to motivate the users to donate or sell their old devices and make electronic use more sustainable, data privacy on second-hand smartphone market should be significantly improved. Presented research has been carried out in the framework of sustainablySMART project, which is part of Horizon 2020 EU Framework Programme for Research and Innovation.

Keywords: android, circular economy, data privacy, second-hand phones

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Authors: Mohd Javaid, Shahbaz Khan, Abid Haleem

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Purpose: Large numbers of 3D printing technologies are now available for sophisticated applications in different fields. Additive manufacturing has established its dominance in design, development, and customisation of the product. In the era of developing technologies, there is a need to identify the appropriate technology for different application. In order to fulfil this need, two widely used printing technologies such as Fused Deposition Modeling (FDM), and Binding-Jet 3D Printing are compared for effective utilisation in the current scenario for different applications. Methodology: Systematic literature review conducted for both technologies with applications and associated factors enabling for the same. Appropriate MCDM tool is used to compare critical factors for both the technologies. Findings: Both technologies have their potential and capabilities to provide better direction to the industry. Additionally, this paper is helpful to develop a decision support system for the proper selection of technologies according to their continuum of applications and associated research and development capability. The vital issue is raw materials, and research-based material development is key to the sustainability of the developed technologies. FDM is a low-cost technology which provides high strength product as compared to binding jet technology. Researcher and companies can take benefits of this study to achieve the required applications in lesser resources. Limitations: Study has undertaken the comparison with the opinion of experts, which may not always be free from bias, and some own limitations of each technology. Originality: Comparison between these technologies will help to identify best-suited technology as per the customer requirements. It also provides development in this different field as per their extensive capability where these technologies can be successfully adopted. Conclusion: FDM and binding jet technology play an active role in industrial development. These help to assist the customisation and production of personalised parts cost-effectively. So, there is a need to understand how these technologies can provide these developments rapidly. These technologies help in easy changes or in making revised versions of the product, which is not easily possible in the conventional manufacturing system. High machine cost, the requirement of skilled human resources, low surface finish, and mechanical strength of product and material changing option is the main limitation of this technology. However, these limitations vary from technology to technology. In the future, these technologies are to be commercially viable for efficient usage in direct manufacturing of varied parts.

Keywords: 3D printing, comparison, fused deposition modeling, FDM, binding jet technology

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Authors: Philippe Judlin, Olivier Morel

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Background: In France, the resident curriculum (RC) in Obstetrics and Gynecology (OBGYN) takes five years. In the course of the last 15 years, this RC has undergone major changes, characterized mainly by successive reductions of work hours. The program used to comprise long and frequent shifts, huge workload, poor supervision and erratic theoretical teaching. A decade ago, the French Ministry of Heath recommended a limitation of shift duration up to 24 hours and a minimum of 11 hours off duty between shifts. Last year, in order to comply with European Union directives, new recommendations have further limited residents’ work hours to 48 hours per week. Methods: Assessment of the residency program adjustments recently made to accommodate the recommendations while improving the training quality in resorting to new methods. Results: The challenge facing program directors was to provide an all-encompassing curriculum to OBGYN residents despite fewer work hours. Program has been dramatically redesigned, and several measures have been put in place: -The resident rotation system has been redesigned. Residents used to make 6-month rotations between 10-12 Departments of OBGYN or Surgery. Fewer Departments, those providing the best teaching, have been kept in the new RC. -Extensive inhouse supervision has been implemented for all kinds of clinical activities. Effectual supervision of residents has proved to be an effective tool to improve the quality of training. -The tutorship system, with academic members individually overseeing residents during their curriculum, has been perfected. It allows a better follow-up of residents’ progresses during the 5-year program. -The set up of an extensive program of lectures encompassing all maters in Obstetrics & Gynecology. These mandatory lectures are available online in a dedicated website. Therefore, face-to-face lectures have been limited in order to fit in the 48-hour limit. -The use of simulation has been significantly increased in obstetrics, materno-fetal medicine and surgery (stressing especially laparoscopic training). -Residents’ feedback has been taken into account in the setup of the new RC. Conclusion: This extensive overhaul of the Obstetrics and Gynecology RC has been in place since last year only. Nevertheless, the new program seems to adequately take into account the new recommendations while providing a better and more consistent teaching to the OBGYN residents.

Keywords: education, laparoscopy, residency, simulation

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Authors: J. F. Gonzalez-Rojo, Federico Lluesma-Rodriguez, Temoatzin Gonzalez

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Hyperloop, a new mode of transport, is gaining significance. It consists of the use of a ground-based transport system which includes a levitation system, that avoids rolling friction forces, and which has been covered with a tube, controlling the inner atmosphere lowering the aerodynamic drag forces. Thus, hyperloop is proposed as a solution to the current limitation on ground transportation. Rolling and aerodynamic problems, that limit large speeds for traditional high-speed rail or even maglev systems, are overcome using a hyperloop solution. Zeleros is one of the companies developing technology for hyperloop application worldwide. It is working on a concept that reduces the infrastructure cost and minimizes the power consumption as well as the losses associated with magnetic drag forces. For this purpose, Zeleros proposes a Hybrid ElectroMagnetic Suspension (EMS) for its prototype. In the present manuscript an active and optimal electromagnetic suspension levitation method based on nearly zero power consumption individual modules is presented. This system consists of several hybrid permanent magnet-coil levitation units that can be arranged along the vehicle. The proposed unit manages to redirect the magnetic field along a defined direction forming a magnetic circuit and minimizing the loses due to field dispersion. This is achieved using an electrical steel core. Each module can stabilize the gap distance using the coil current and either linear or non-linear control methods. The ratio between weight and levitation force for each unit is 1/10. In addition, the quotient between the lifted weight and power consumption at the target gap distance is 1/3 [kg/W]. One degree of freedom (DoF) (along the gap direction) is controlled by a single unit. However, when several units are present, a 5 DoF control (2 translational and 3 rotational) can be achieved, leading to the full attitude control of the vehicle. The proposed system has been successfully tested reaching TRL-4 in a laboratory test bench and is currently in TRL-5 state development if the module association in order to control 5 DoF is considered.

Keywords: active optimal control, electromagnetic levitation, HEMS, high-speed transport, hyperloop

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Authors: Adrianna D. Hendricks

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This paper examines the factors that contribute to the re-traumatization of victims of sex trafficking within the Canadian context. Sex trafficking occurring domestically in Canada is severely under-researched, stigmatized, and under-prosecuted, leading to the re-traumatization of victims by various levels of government. This is in part due to the Canadian criminal justice system unethically utilizing prostitution laws in cases of sex trafficking and partially due to the unaddressed stigmatization victims face within the justice system itself. Utilizing evidence from a current literature review, personal correspondence, and personal life experiences, this paper will demonstrate the need for victim involvement in policy reform. The current literature review was done through an academic database search using the terms: “Sex Trafficking, Exploitation, Canada”, with the limitation of articles written within the last 5 years and written within the Canadian context. Overall, from the results, only eight articles precisely matched the criteria. The current literature argues strongly and unanimously for more research and education of professionals who have close contact with high-risk populations (doctors, police officers, social workers, etc.) to protect both minors and adults from being sexually trafficked. Additionally, for women and girls who do not have Canadian citizenship, the fear of deportation becomes a barrier to disclosing exploitation experiences to professionals. There is a desperate need for more research done in tandem with survivors and victims to inform policymaking in a meaningful way. The researcher is a survivor of sex trafficking both as a youth and as an adult, giving the researcher a unique insight into the realities of the criminal justice system for victims of sex trafficking. There is a clear need for professionals in positions of power to be re-educated about the realities of sex-trafficking, and what it means for the victims. Congruent to the current research the author calls for: standardized professional training for people in healthcare, police officers, court officials, and victim services; with the additional layers of victim involvement in creation of professional education training, and victim involvement in research. Justice for victims/survivors can only be obtained if they have been consulted and believed. Without meaningful consultation with survivors, victims who are both minors and adults will continue to fall through the cracks in policy.

Keywords: Canadian policy, re-traumatization, sex-trafficking, stigmatization

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Authors: Emiru Birhane, Tesfay Gidey, Haftu Abrha, Abrha Brhan, Amanuel Zenebe, Girmay Gebresamuel, Florent Noulèkoun

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Dracaena ombet and Dobera glabra are two of the most rare and endangered tree species in dryland areas. Unfortunately, their sustainability is being compromised by different anthropogenic and natural factors. However, the impacts of ongoing land use and climate change on the population structure and distribution of the species are less explored. This study was carried out in the grazing lands and hillside areas of the Desa'a dry Afromontane forest, northern Ethiopia, to characterize the population structure of the species and predict the impact of climate change on their potential distributions. In each land-use type, abundance, diameter at breast height, and height of the trees were collected using 70 sampling plots distributed over seven transects spaced one km apart. The geographic coordinates of each individual tree were also recorded. The results showed that the species populations were characterized by low abundance and unstable population structure. The latter was evinced by a lack of seedlings and mature trees. The study also revealed that the total abundance and dendrometric traits of the trees were significantly different between the two land uses. The hillside areas had a denser abundance of bigger and taller trees than the grazing lands. Climate change predictions using the MaxEnt model highlighted that future temperature increases coupled with reduced precipitation would lead to significant reductions in the suitable habitats of the species in northern Ethiopia. The species' suitable habitats were predicted to decline by 48–83% for D. ombet and 35–87% for D. glabra. Hence, to sustain the species populations, different strategies should be adopted, namely the introduction of alternative livelihoods (e.g., gathering NTFP) to reduce the overexploitation of the species for subsistence income and the protection of the current habitats that will remain suitable in the future using community-based exclosures. Additionally, the preservation of the species' seeds in gene banks is crucial to ensure their long-term conservation.

Keywords: grazing lands, hillside areas, land-use change, MaxEnt, range limitation, rare and endangered tree species

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Authors: Xiaoyu Shen, Fang Fang, Chujun Qiu

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Herewith we present a Fourier method for credit risk quantification and allocation in the factor-copula model framework. The key insight is that, compared to directly computing the cumulative distribution function of the portfolio loss via Monte Carlo simulation, it is, in fact, more efficient to calculate the transformation of the distribution function in the Fourier domain instead and inverting back to the real domain can be done in just one step and semi-analytically, thanks to the popular COS method (with some adjustments). We also show that the Euler risk allocation problem can be solved in the same way since it can be transformed into the problem of evaluating a conditional cumulative distribution function. Once the conditional or unconditional cumulative distribution function is known, one can easily calculate various risk metrics. The proposed method not only fills the niche in literature, to the best of our knowledge, of accurate numerical methods for risk allocation but may also serve as a much faster alternative to the Monte Carlo simulation method for risk quantification in general. It can cope with various factor-copula model choices, which we demonstrate via examples of a two-factor Gaussian copula and a two-factor Gaussian-t hybrid copula. The fast error convergence is proved mathematically and then verified by numerical experiments, in which Value-at-Risk, Expected Shortfall, and conditional Expected Shortfall are taken as examples of commonly used risk metrics. The calculation speed and accuracy are tested to be significantly superior to the MC simulation for real-sized portfolios. The computational complexity is, by design, primarily driven by the number of factors instead of the number of obligors, as in the case of Monte Carlo simulation. The limitation of this method lies in the "curse of dimension" that is intrinsic to multi-dimensional numerical integration, which, however, can be relaxed with the help of dimension reduction techniques and/or parallel computing, as we will demonstrate in a separate paper. The potential application of this method has a wide range: from credit derivatives pricing to economic capital calculation of the banking book, default risk charge and incremental risk charge computation of the trading book, and even to other risk types than credit risk.

Keywords: credit portfolio, risk allocation, factor copula model, the COS method, Fourier method

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Authors: Rady A., Elsheshai A., Elsawy M., Nagui R.

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Background and Aim: Metabolic syndrome affect around 20% of general population , authors have incriminated antipsychotics as serious risk factor that may provoke such derangement. The aim of our study is to assess metabolic syndrome in patients presenting psychotic features (delusions and hallucinations) whether schizophrenia or mood disorder and compare results in terms of drug naïf, on medication and healthy control. Subjects and Methods: The study recruited 40 schizophrenic patients, half of them drug naïf and the other half on antipsychotics, 40 patients with mood disorder with psychotic features, half of them drug naïf and the other half on medication, 20 healthy control. Exclusion criteria were put in order to exclude patients having already endocrine or metabolic disorders that my interfere with results obtain to minimize confusion bias. Metabolic syndrome assessed by measuring parameters including weight, body mass index, waist circumference, triglyceride level, HDL, fasting glucose, fasting insulin and insulin resistance Results: No difference was found when comparing drug naïf to those on medication in both schizophrenic and psychotic mood disorder arms, schizophrenic patients whether on medication or drug naïf should difference with control group for fasting glucose, schizophrenic patients on medication also showed difference in insulin resistance compared to control group. On the other hand, patients with psychotic mood disorder whether drug naïf or on medication showed difference from control group for fasting insulin level. Those on medication also differed from control for insulin resistance Conclusion: Our study didn’t reveal difference in metabolic syndrome among patients with psychotic features whether on medication or drug naïf. Only patients with Psychotic features on medication showed insulin resistance. Schizophrenic patients drug naïf or on medication tend to show higher fasting glucose while psychotic mood disorder whether drug naïf or on medication tend to show higher fasting insulin. This study suggest that presence of psychotic features themselves regardless being on medication or not carries a risk for insulin resistance and metabolic syndrome. Limitation: This study is limited by number of participants and larger numbers in future studies should be included in order to extrapolate results. Cohort longitudinal studies are needed in order to evaluate such hypothesis.

Keywords: schizophrenia, metabolic syndrome, psychosis, insulin, resistance

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Authors: I. Dangeard, S. Meineri, M. Dupré

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large body of research on energy consumption reveals that regular information on energy consumption produces a positive effect on behavior. The present research aims to test this feedback paradigm on waste management. A small-scale experiment on residual household waste was performed in a large french urban area, in partnership with local authorities, as part of the development of larger-scale project. A two-step door-to-door recruitment scheme led to 85 households answering a questionnaire. Among them, 54 accepted to participate in a study on waste (second step). Participants were then randomly assigned to one of the 3 experimental conditions : self-reported feedback on curbside waste, external feedback on waste weight based on information technologies, and no feedback for the control group. An additional control group was added, including households who were not requested to answer the questionnaire. Household residual waste was collected every week, and tags on curbside bins fed a database with waste weight of households. The feedback period lasted 14 weeks (february-may 2014). Quantitative data on waste weight were analysed, including these 14 weeks and the 7 previous weeks. Households were then contacted by phone in order to confirm the quantitative results. Regarding the recruitment questionnaire, results revealed high pro-environmental attitude on the NEP scale, high recycling behavior level and moderate level of source reduction behavior on the adapted 3R scale, but no statistical difference between the 3 experimental groups. Regarding the feedback manipulation paradigm, waste weight reveals important differences between households, but doesn't prove any statistical difference between the experimental conditions. Qualitative phone interviews confirm that recycling is a current practice among participants, whereas source reduction of waste is not, and mainly appears as a producer problem of packaging limitation. We conclude that triggering waste prevention behaviors among recycling households involves long-term feedback and should promote benchmarking, in order to clearly set waste reduction as an objective to be managed through feedback figures.

Keywords: eco-feedback, household waste, waste reduction, experimental research

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Authors: M. Moyzykh, I. Klichuk, L. Sabirov, D. Kolomentseva, E. Magommedov

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Modern city electrical grids are forced to increase their density due to the increasing number of customers and requirements for reliability and resiliency. However, progress in this direction is often limited by the capabilities of existing network equipment. New energy sources or grid connections increase the level of short-circuit currents in the adjacent network, which can exceed the maximum rating of equipment–breaking capacity of circuit breakers, thermal and dynamic current withstand qualities of disconnectors, cables, and transformers. Superconducting fault current limiter (SFCL) is a modern solution designed to deal with the increasing fault current levels in power grids. The key feature of this device is its instant (less than 2 ms) limitation of the current level due to the nature of the superconductor. In 2019 Moscow utilities installed SuperOx SFCL in the city power grid to test the capabilities of this novel technology. The SFCL became the first SFCL in the Russian energy system and is currently the most powerful SFCL in the world. Modern SFCL uses second-generation high-temperature superconductor (2G HTS). Despite its name, HTS still requires low temperatures of liquid nitrogen for operation. As a result, Moscow SFCL is built with a cryogenic system to provide cooling to the superconductor. The cryogenic system consists of three cryostats that contain a superconductor part and are filled with liquid nitrogen (three phases), three cryocoolers, one water chiller, three cryopumps, and pressure builders. All these components are controlled by an automatic control system. SFCL has been continuously operating on the city grid for over three years. During that period of operation, numerous faults occurred, including cryocooler failure, chiller failure, pump failure, and others (like a cryogenic system power outage). All these faults were eliminated without an SFCL shut down due to the specially designed cryogenic system backups and quick responses of grid operator utilities and the SuperOx crew. The paper will describe in detail the results of SFCL operation and cryogenic system maintenance and what measures were taken to solve and prevent similar faults in the future.

Keywords: superconductivity, current limiter, SFCL, HTS, utilities, cryogenics

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Authors: Emigdio Mendoza, Patricia Fernandez, Cristian Gomez

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Magnesium alloys have generated great interest for several industrial applications because their high specific strength and low density make them a very attractive alternative for the manufacture of various components; however, these alloys present a limitation with their hexagonal crystal structure that limits the deformation mechanisms at room temperature likewise the molding components alternatives, it is for this reason that severe plastic deformation processes have taken a huge relevance recently because these, allow high deformation rates to be applied that induce microstructural changes where the deficiency in the sliding systems is compensated with crystallographic grains reorientations or crystal twinning. The present study reports a statistical analysis of process temperature, number of passes and shear angle with respect to the shear stress in severe plastic deformation process denominated 'Equal Channel Angular Sheet Drawing (ECASD)' applied to the magnesium alloy AZ31B through Python Statsmodels libraries, additionally a Post-Hoc range test is performed using the Tukey statistical test. Statistical results show that each variable has a p-value lower than 0.05, which allows comparing the average values of shear stresses obtained, which are in the range of 7.37 MPa to 12.23 MPa, lower values in comparison to others severe plastic deformation processes reported in the literature, considering a value of 157.53 MPa as the average creep stress for AZ31B alloy. However, a higher stress level is required when the sheets are processed using a shear angle of 150°, due to a higher level of adjustment applied for the shear die of 150°. Temperature and shear passes are important variables as well, but there is no significant impact on the level of stress applied during the ECASD process. In the processing of AZ31B magnesium alloy sheets, ECASD technique is evidenced as a viable alternative in the modification of the elasto-plastic properties of this alloy, promoting the weakening of the basal texture, which means, a better response to deformation, whereby, during the manufacture of parts by drawing or stamping processes the formation of cracks on the surface can be reduced, presenting an adequate mechanical performance.

Keywords: plastic deformation, strain, sheet drawing, magnesium

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Authors: Olufunmilola A. Abiodun, Adegbola O. Dauda, Ayobami Ojo, Samson A. Oyeyinka

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Blighia sapida (Ackee) seed is a neglected and under-utilised crop. The fruit is cultivated for the aril which is used as meat substitute in soup while the seed is discarded. The seed is toxic due to the presence of hypoglycin which causes vomiting and death. The seed is shining black and bigger than the legume seeds. The seed contains high starch content which could serve as a cheap source of starch hereby reducing wastage of the crop during its season. Native starch had limitation in their use; therefore, modification of starch had been reported to improve the functional properties of starches. Therefore, this work determined the effect of modification on the properties of Blighia sapida seed starch. Blighia sapida seed was dehulled manually, milled and the starch extracted using standard method. The starch was subjected to modification using four methods (acid, alkaline, oxidized and acetylated methods). The morphological structure, form factor, granule size, amylose, swelling power, hypoglycin and pasting properties of the starches were determined. The structure of Blighia sapida using light microscope showed that the seed starch demonstrated an oval, round, elliptical, dome-shaped and also irregular shape. The form factors of the starch ranged from 0.32-0.64. Blighia sapida seed starches were smaller in granule sizes ranging from 2-6 µm. Acid modified starch had the highest amylose content (24.83%) and was significantly different ( < 0.05) from other starches. Blighia sapida seed starches showed a progressive increase in swelling power as temperature increased in native, acidified, alkalized, oxidized and acetylated starches but reduced with increasing temperature in pregelatinized starch. Hypoglycin A ranged from 3.89 to 5.74 mg/100 g with pregelatinized starch having the lowest value and alkalized starch having the highest value. Hypoglycin B ranged from 7.17 to 8.47 mg/100 g. Alkali-treated starch had higher peak viscosity (3973 cP) which was not significantly different (p > 0.05) from the native starch. Alkali-treated starch also was significantly different (p > 0.05) from other starches in holding strength value while acetylated starch had higher breakdown viscosity (1161.50 cP). Native starch was significantly different (p > 0.05) from other starches in final and setback viscosities. Properties of Blighia sapida modified starches showed that it could be used as a source of starch in food and other non-food industries and the toxic compound found in the starch was very low when compared to lethal dosage.

Keywords: Blighia sapida seed, modification, starch, hypoglycin

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Authors: Oti Ibiam, Alexanda O. Kalu

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Human Resource Accounting is the process of identifying and measuring data about human resources and communicating this information to interested parties in order to meaningful investment decisions. In recent time, firms focus has shifted to human resource accounting so as to ensure efficiency and effectiveness in their operations. This study focused on the effect of human resource accounting on the financial performance of Banks in Nigerian. The problem that led to the study revolves around the current trend whereby Nigeria banks do not efficiently account for the input of human resource in their annual statement, thereby instead of capitalizing human resources in their statement of financial position; they expend it in their income statement thereby reducing their profit after tax. The broad objective of this study is to determine the extent to which human resource accounting affects the financial performance and value of Nigerian Banks. This study is therefore considered significant because, there are still universally, grey areas to be sorted out on the subject matter of human resources accounting. In the bid to achieve the study objectives, the researcher gathered data from sixteen commercial banks. Data were collected from both primary and secondary sources using an ex-post facto research design. The data collected were then tabulated and analyzed using the multiple regression analysis. The result of hypothesis one revealed that there is a significant relationship between Capitalized Human Resource Cost and post capitalization Profit before tax of banks in Nigeria. The finding of hypothesis two revealed that the association between Capitalized Human Resource Cost and post capitalization Net worth of banks in Nigeria is significant. The finding in Hypothesis three reveals that there is a significant difference between pre and post capitalization profit before tax of banks in Nigeria. The study concludes that human resources accounting positively influenced financial performance of banks in Nigeria within the period under study. It is recommended that standards should be set for human resources identification and measurement in the banking sector and also the management of commercial banks in Nigeria should have a proper appreciation of human resource accounting. This will enable managers to take right decision regarding investment in human resource. Also, the study recommends that policies on enhancing the post capitalization profit before tax of banks in Nigeria should pay great attention to capitalized human resources cost, net worth and total asset as the variables significantly influenced post capitalization profit before tax of the studied banks in Nigeria. The limitation of the study centers on the limited number of years and companies that was adopted for the study.

Keywords: capitalization, human resources cost, profit before tax, net worth

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Authors: Jose Neri, Fabrice Canto, Alastair Magnaldo, Laurent Guillerme, Vincent Dugas

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A miniaturized and automated approach for the volumetric titration of free nitric acid in U(VI) solutions is presented. Free acidity measurement refers to the acidity quantification in solutions containing hydrolysable heavy metal ions such as U(VI), U(IV) or Pu(IV) without taking into account the acidity contribution from the hydrolysis of such metal ions. It is, in fact, an operation having an essential role for the control of the nuclear fuel recycling process. The main objective behind the technical optimization of the actual ‘beaker’ method was to reduce the amount of radioactive substance to be handled by the laboratory personnel, to ease the instrumentation adjustability within a glove-box environment and to allow a high-throughput analysis for conducting more cost-effective operations. The measurement technique is based on the concept of the Taylor-Aris dispersion in order to create inside of a 200 μm x 5cm circular cylindrical micro-channel a linear concentration gradient in less than a second. The proposed analytical methodology relies on the actinide complexation using pH 5.6 sodium oxalate solution and subsequent alkalimetric titration of nitric acid with sodium hydroxide. The titration process is followed with a CCD camera for fluorescence detection; the neutralization boundary can be visualized in a detection range of 500nm- 600nm thanks to the addition of a pH sensitive fluorophore. The operating principle of the developed device allows the active generation of linear concentration gradients using a single cylindrical micro channel. This feature simplifies the fabrication and ease of use of the micro device, as it does not need a complex micro channel network or passive mixers to generate the chemical gradient. Moreover, since the linear gradient is determined by the liquid reagents input pressure, its generation can be fully achieved in faster intervals than one second, being a more timely-efficient gradient generation process compared to other source-sink passive diffusion devices. The resulting linear gradient generator device was therefore adapted to perform for the first time, a volumetric titration on a chip where the amount of reagents used is fixed to the total volume of the micro channel, avoiding an important waste generation like in other flow-based titration techniques. The associated analytical method is automated and its linearity has been proven for the free acidity determination of U(VI) samples containing up to 0.5M of actinide ion and nitric acid in a concentration range of 0.5M to 3M. In addition to automation, the developed analytical methodology and technique greatly improves the standard off-line oxalate complexation and alkalimetric titration method by reducing a thousand fold the required sample volume, forty times the nuclear waste per analysis as well as the analysis time by eight-fold. The developed device represents, therefore, a great step towards an easy-to-handle nuclear-related application, which in the short term could be used to improve laboratory safety as much as to reduce the environmental impact of the radioanalytical chain.

Keywords: free acidity, lab-on-a-chip, linear concentration gradient, Taylor-Aris dispersion, volumetric titration

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Authors: Satya P. Dubey, Hrushikesh A Abhyankar, Veronica Marchante, James L. Brighton, Björn Bergmann

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Aims: To develop a mathematical model that simulates the ROP of PLA taking into account the effect of alternative energy to be implemented in a continuous reactive extrusion production process of PLA. Introduction: The production of large amount of waste is one of the major challenges at the present time, and polymers represent 70% of global waste. PLA has emerged as a promising polymer as it is compostable, biodegradable thermoplastic polymer made from renewable sources. However, the main limitation for the application of PLA is the traces of toxic metal catalyst in the final product. Thus, a safe and efficient production process needs to be developed to avoid the potential hazards and toxicity. It has been found that alternative energy sources (LASER, ultrasounds, microwaves) could be a prominent option to facilitate the ROP of PLA via continuous reactive extrusion. This process may result in complete extraction of the metal catalysts and facilitate less active organic catalysts. Methodology: Initial investigation were performed using the data available in literature for the reaction mechanism of ROP of PLA based on conventional metal catalyst stannous octoate. A mathematical model has been developed by considering significant parameters such as different initial concentration ratio of catalyst, co-catalyst and impurity. Effects of temperature variation and alternative energies have been implemented in the model. Results: The validation of the mathematical model has been made by using data from literature as well as actual experiments. Validation of the model including alternative energies is in progress based on experimental data for partners of the InnoREX project consortium. Conclusion: The model developed reproduces accurately the polymerisation reaction when applying alternative energy. Alternative energies have a great positive effect to increase the conversion and molecular weight of the PLA. This model could be very useful tool to complement Ludovic® software to predict the large scale production process when using reactive extrusion.

Keywords: polymer, poly-lactic acid (PLA), ring opening polymerization (ROP), metal-catalyst, bio-degradable, renewable source, alternative energy (AE)

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Authors: Chen Zhang, Yongpeng Gu, Xiaotian Li

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Quasi-zero-stiffness (QZS) vibration isolation technology has garnered significant attention in both academia and industry, which enables ultra-low-frequency vibration isolation. In modern industries, such as shipbuilding and aerospace, rotating machinery generates vibrations over a wide frequency range, thus imposing more stringent requirements on vibration isolation technologies. These technologies must not only achieve ultra-low starting isolation frequencies but also provide effective isolation across mid- to high-frequency ranges. However, existing research on QZS vibration isolators primarily focuses on frequency ranges below 50 Hz. Moreover, studies have shown that in the mid-to high-frequency ranges, QZS isolators tend to generate resonance peaks that adversely affect their isolation performance. This limitation significantly restricts the practical applicability of QZS isolation technology. To address this issue, the present study investigates the high-frequency isolation performance of two typical QZS isolators: the mechanism type three-spring QZS isolator mechanism and the structure and bowl-shaped QZS isolator structure. First, the parameter conditions required to achieve quasi-zero stiffness characteristics for two isolators are derived based on static mechanical analysis. The theoretical transmissibility characteristics are then calculated using the harmonic balance method. Three-dimensional finite element models of two QZS isolators are developed using ABAQUS simulation software, and transmissibility curves are computed for the 0-500 Hz frequency range. The results indicate that the three-spring QZS mechanism exhibits multiple higher-order resonance peaks in the mid-to high-frequency ranges due to the higher-order models of the springs. Springs with fewer coils and larger diameters can shift the higher-order modals to higher frequencies but cannot entirely eliminate their occurrence. In contrast, the bowl-shaped QZS isolator, through shape optimization using a spline-based representation, effectively mitigates the generation of higher-order resonance modes, resulting in superior isolation performance in the mid-to high-frequency ranges. This study provides essential theoretical insights for optimizing the vibration isolation performance of QZS technologies in complex, wide-frequency vibration environments, offering significant practical value for their application.

Keywords: quasi-zero-stiffness, wide-frequency vibration, vibration isolator, transmissibility

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Authors: Kiran Nawaz, Ahmad Ali Shahid, Sehrish Iftikhar, Waheed Anwar, Muhammad Nasir Subhani

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Chili (Solanum annum L.) attacks by many fungal pathogens, including members of Oomycetes which are responsible for root rot in different chili growing areas of the world. Oomycetes pathogens cause economic losses in different regions of the Pakistan. Most of the plant tissues, including roots, crowns, fruit, and leaves, are vulnerable to Phytophthora capsici. It is very difficult to manage the Phytophthora root rot of chili as many commercial varieties are tremendously vulnerable to P. capsici. The causal agent of the disease was isolated on corn meal agar (CMA) and identified on a morphological basis by using available taxonomic keys. The pathogen was also confirmed on the molecular basis through internal transcribed spacer region and with other molecular markers.The Blastn results showed 100% homology with already reported sequences of P. capsici in NCBI database. Most of the farmers have conventionally relied on foliar fungicide applications to control Phytophthora root rot in spite of their incomplete effectiveness. In this study, in vitro plate assay, seed soaking and foliar applications of 6 fungicides were evaluated against root rot of chili. In vitro assay revealed that significant inhibition of linear growth was obtained with Triflumizole at 7.0%, followed by Thiophanate methyl (8.9%), Etridiazole (6.0%), Propamocarb (5.9%) and 7.5% with Mefenoxam and Iprodione for P. capsici. The promising treatments of in vitro plate bioassay were evaluated in pot experiments under controlled conditions in the greenhouse. All fungicides were applied after at 6-day intervals. Results of pot experiment showed that all treatments considerably inhibited the percentage of P. capsici root rot incidence. In addition, application of seed soaking with all six fungicides combined with the foliar spray of the same components showed the significant reduction in root rot incidence. The combine treatments of all fungicides as in vitro bioassay, seed soaking followed by foliar spray is considered non-harmful control methods which have advantages and limitation. Hence, these applications proved effective and harmless for the management of soil-borne plant pathogens.

Keywords: blastn, bioassay, corn meal agar(CMA), oomycetes

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Authors: Doran C. Kalmin

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The descending genicular artery (DGA) perforator free flap provides an alternative to free flap reconstruction based on a review of the literature detailing both anatomical and clinical studies. The descending genicular artery (DGA) supplies skin, muscle, tendon, and bone located around the medial aspect of the knee that has been used in several pioneering reports in reconstructing defects located in various areas throughout the body. After the success of the medial femoral condyle flap in early studies, a small number of studies have been published detailing the use of the DGA in free flap reconstruction. Despite early success in the use of the DGA flap, acceptance within the Plastic and Reconstructive Surgical community has been limited due primarily to anatomical variations of the pedicle. This literature review is aimed at detailing the progression of the DGA perforator free flap and its variations as an alternative and reliable free flap for reconstruction of composite defects with an exploration into both anatomical and clinical studies. A literature review was undertaken, and the progression of the DGA flap is explored from the early review by Acland et al. pioneering the saphenous free flap to exploring modern changes and studies of the anatomy of the DGA. An extensive review of the literature was undertaken that details the anatomy and its variations, approaches to harvesting the flap, the advantages, and disadvantages of the DGA perforator free flap as well as flap outcomes. There are 15 published clinical series of DGA perforator free flaps that incorporate cutaneous, osteoperiosteal, cartilage, osteocutaneous, osteoperiosteal and muscle, osteoperiosteal and subcutaneous and tendocutatenous. The commonest indication for using a DGA free flap was for non-union of bone, particularly that of the scaphoid whereby the medial femoral condyle could be used. In the case series, a success rate of over 90% was established, showing that these early studies have had good success with a wide range of tissue transfers. The greatest limitation is the anatomical variation of the DGA and therefore, the challenges associated with raising the flap. Despite the variation in anatomy and around 10-15% absence of the DGA, the saphenous artery can be used as well as the superior medial genicular artery if the vascular bone is required as part of the flap. Despite only a handful of anatomical and clinical studies describing the DGA perforator free flap, it ultimately provides a reliable flap that can include a variety of composite structure used for reconstruction in almost any area throughout the body. Although it has limitations, it provides a reliable option for free flap reconstruction that can routinely be performed as a single-stage procedure.

Keywords: anatomical study, clinical study, descending genicular artery, literature review, perforator free flap reconstruction

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Authors: Zeineb Baatout, Safa Teka, Nejmeddine Jaballah, Nawfel Sakly, Xiaonan Sun, Mustapha Majdoub

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Currently, the economic interests linked to the development of bio-based materials make biomass one of the most interesting areas for science development. We are interested in the β-cyclodextrin (β-CD), one of the popular bio-sourced macromolecule, produced from the starch via enzymatic conversion. It is a cyclic oligosaccharide formed by the association of seven glucose units. It presents a rigid conical and amphiphilic structure with hydrophilic exterior, allowing it to be water-soluble. It has also a hydrophobic interior enabling the formation of inclusion complexes, which support its application for the elaboration of electrochemical and optical sensors. Nevertheless, the solubility of β-CD in water makes its use as sensitive layer limit and difficult due to their instability in aqueous media. To overcome this limitation, we chose to precede by modification of the hydroxyl groups to obtain hydrophobic derivatives which lead to water-stable sensing layers. Hence, a series of benzylated β-CDs were synthesized in basic aqueous media in one pot. This work reports the synthesis of a new family of substituted amphiphilic β-CDs using a green methodology. The obtained β-CDs showed different degree of substitution (DS) between 0.85 and 2.03. These organic macromolecular materials were soluble in common organic volatile solvents, and their structures were investigated by NMR, FT-IR and MALDI-TOF spectroscopies. Thermal analysis showed a correlation between the thermal properties of these derivatives and the benzylation degree. The surface properties of the thin films based on the benzylated β-CDs were characterized by contact angle measurements and atomic force microscopy (AFM). These organic materials were investigated as sensitive layers, deposited on quartz crystal microbalance (QCM) gravimetric transducer, for humidity sensor at room temperature. The results showed that the performances of the prepared sensors are greatly influenced by the benzylation degree of β-CD. The partially modified β-CD (DS=1) shows linear response with best sensitivity, good reproducibility, low hysteresis, fast response time (15s) and recovery time (17s) at higher relative humidity levels (RH) between 11% and 98% in room temperature.

Keywords: β-cyclodextrin, green synthesis, humidity sensor, quartz crystal microbalance

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Authors: Varun Dongre, Stefan Pirker, Stefan Heinrich

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Over the last decades, the numerical modelling of fluidized bed processes has become feasible even for industrial processes. Commonly, continuous two-fluid models are applied to describe large-scale fluidization. In order to allow for coarse grids novel two-fluid models account for unresolved sub-grid heterogeneities. However, computational efforts remain high – in the order of several hours of compute-time for a few seconds of real-time – thus preventing the representation of long-term phenomena such as heating or particle conversion processes. In order to overcome this limitation, data-based recurrence computational fluid dynamics (rCFD) has been put forward in recent years. rCFD can be regarded as a data-based method that relies on the numerical predictions of a conventional short-term simulation. This data is stored in a database and then used by rCFD to efficiently time-extrapolate the flow behavior in high spatial resolution. This study will compare the numerical predictions of rCFD simulations with those of corresponding full CFD reference simulations for lab-scale and pilot-scale fluidized beds. In assessing the predictive capabilities of rCFD simulations, we focus on solid mixing and secondary gas holdup. We observed that predictions made by rCFD simulations are highly sensitive to numerical parameters such as diffusivity associated with face swaps. We achieved a computational speed-up of four orders of magnitude (10,000 time faster than classical TFM simulation) eventually allowing for real-time simulations of fluidized beds. In the next step, we apply the checkerboarding technique by introducing gas tracers subjected to convection and diffusion. We then analyze the concentration profiles by observing mixing, transport of gas tracers, insights about the convective and diffusive pattern of the gas tracers, and further towards heat and mass transfer methods. Finally, we run rCFD simulations and calibrate them with numerical and physical parameters compared with convectional Two-fluid model (full CFD) simulation. As a result, this study gives a clear indication of the applicability, predictive capabilities, and existing limitations of rCFD in the realm of fluidization modelling.

Keywords: multiphase flow, recurrence CFD, two-fluid model, industrial processes

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Authors: V. Radulescu, S. Dumitru

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Introduction: Determination of the temperature field inside a fluid in motion has many practical issues, especially in the case of turbulent flow. The phenomenon is greater when the solid walls have a different temperature than the fluid. The turbulent heat and mass transfer have an essential role in case of the thermal pollution, as it was the recorded during the damage of the Thermoelectric Power-plant Oradea (closed even today). Basic Methods: Solving the theoretical turbulent thermal pollution represents a particularly difficult problem. By using the semi-empirical theories or by simplifying the made assumptions, based on the experimental measurements may be assured the elaboration of the mathematical model for further numerical simulations. The three zones of flow are analyzed separately: the vicinity of the solid wall, the turbulent transition zone, and the turbulent core. For each area are determined the distribution law of temperature. It is determined the dependence of between the Stanton and Prandtl numbers with correction factors, based on measurements experimental. Major Findings/Results: The limitation of the laminar thermal substrate was determined based on the theory of Landau and Levice, using the assumption that the longitudinal component of the velocity pulsation and the pulsation’s frequency varies proportionally with the distance to the wall. For the calculation of the average temperature, the formula is used a similar solution as for the velocity, by an analogous mediation. On these assumptions, the numerical modeling was performed with a gradient of temperature for the turbulent flow in pipes (intact or damaged, with cracks) having 4 different diameters, between 200-500 mm, as there were in the Thermoelectric Power-plant Oradea. Conclusions: It was made a superposition between the molecular viscosity and the turbulent one, followed by addition between the molecular and the turbulent transfer coefficients, necessary to elaborate the theoretical and the numerical modeling. The concept of laminar boundary layer has a different thickness when it is compared the flow with heat transfer and that one without a temperature gradient. The obtained results are within the margin of error of 5%, between the semi-empirical classical theories and the developed model, based on the experimental data. Finally, it is obtained a general correlation between the Stanton number and the Prandtl number, for a specific flow (with associated Reynolds number).

Keywords: experimental measurements, numerical correlations, thermal pollution through pipelines, turbulent thermal flow

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Authors: Sasibhushan Yengala, Nelson Muthu, Subramani Kanagaraj

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The abstract reports on the design related to a modular and affordable standing cum sitting device to meet the requirements of paraplegic patients of the different physiques. Paraplegic patients need the assistance of an external arrangement to the lower limbs and trunk to help patients adopt the correct posture while standing abreast gravity. This support can be from a tilt table or a standing frame which the patient can use to stay in a vertical posture. Standing frames are devices fitting to support a person in a weight-bearing posture. Commonly, these devices support and lift the end-user in shifting from a sitting position to a standing position. The merits of standing for a paraplegic patient with a spinal injury are numerous. Even when there is limited control on muscles that ordinarily support the user using the standing frame in a vertical position, the standing stance improves the blood pressure, increases bone density, improves resilience and scope of motion, and improves the user's feelings of well-being by letting the patient stand. One limitation with standing frames is that these devices are typically function definitely; cannot be used for different purposes. Therefore, users are often compelled to purchase more than one of these devices, each being purposefully built for definite activities. Another concern frequent in standing frames is manoeuvrability; it is crucial to provide a convenient adjustment scope for all users. Thus, there is a need to provide a standing frame with multiple uses that can be economical for a larger population. There is also a need to equip added readjustment means in a standing frame to lessen the shear and to accommodate a broad range of users. The proposed Versatile Standing cum Sitting Device (VSD) is designed to change from standing to a comfortable sitting position using a series of mechanisms. First, a locking mechanism is provided to lock the VSD in a standing stance. Second, a dampening mechanism is provided to make sure that the VSD shifts from a standing to a sitting position gradually when the lock mechanism gets disengaged. An adjustment option is offered for the height of the headrest via the use of lock knobs. This device can be used in clinics for rehabilitation purposes irrespective of patient's anthropometric data due to its modular adjustments. It can facilitate the patient's daily life routine while in therapy and giving the patient the comfort to sit when tired. The device also provides the availability of rehabilitation to a common person.

Keywords: paraplegic, rehabilitation, spinal cord injury, standing frame

Procedia PDF Downloads 200

Authors: Tracey Lion-Cachet

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Eating disorders typically manifest in adolescence and are notoriously difficult to treat. There are two notable reasons for this. Firstly, research consistently demonstrates that early intervention is a critical mediator of prognosis, with early intervention leading to a better prognosis. However, because eating disorders do not originate as full-syndrome diagnoses but rather as prodromal cases, they often go undetected; by the time symptoms meet diagnostic criteria, they have become recalcitrant. Another interrelated issue is motivation to change. Research demonstrates that in the early stages of an eating disorder, adolescents are highly resistant to change, and motivation increases only once symptoms have shifted from egosyntonic to egodystonic in nature. The purpose of this project was to design a prevention model based on the social psychology paradigm of Entertainment-Education, which embeds messages within the genre of film as a means of affecting change. The resulting project was a narrative screenplay targeting teenagers/young adults from diverse backgrounds. The goals of the project were to create a film script that, if ultimately made into a film, could serve to: 1) interrupt symptom progression and improve prognosis through early intervention; 2) incorporate techniques from third-wave cognitive behavioral treatment models, acceptance and commitment therapy (ACT) and rational recovery (RR), with a focus on the effects of mindfulness as a means of informing recovery; 3) target issues to do with motivation to change by shifting the perception of eating disorders from culturally specific psychiatric illnesses to habit-based brain wiring issues. Nine licensed clinicians were asked to evaluate two excerpts taken from the final script. They subsequently provided feedback on a Likert-scale, which assessed whether the script had achieved its goals. Overall, evaluators agreed that the project’s etiological and intervention models have the potential to inspire change and serve as an effective means of prevention and treatment of eating disorders. However, one-third of the evaluators did not find the content developmentally appropriate. This is a notable limitation to the study and will need to be addressed in the larger script before the final project can potentially be targeted to a teenage and young adult audience.

Keywords: adolescents, eating disorders, pediatrics, entertainment-education, mindfulness-based intervention, prevention

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Authors: Alena Kulikova, Tatjana Kanonire

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Intelligence research is one of the oldest fields of psychology. Many factors have made a research on intelligence, defined as reasoning and problem solving [1, 2], a very acute and urgent problem. Thus, it has been repeatedly shown that intelligence is a predictor of academic, professional, and social achievement in adulthood (for example, [3]); Moreover, intelligence predicts these achievements better than any other trait or ability [4]. The individual level, a comprehensive assessment of intelligence is a necessary criterion for the diagnosis of various mental conditions. For example, it is a necessary condition for psychological, medical and pedagogical commissions when deciding on educational needs and the most appropriate educational programs for school children. Assessment of intelligence is crucial in clinical psychodiagnostic and needs high-quality intelligence measurement tools. Therefore, it is not surprising that the development of intelligence tests is an essential part of psychological science and practice. Many modern intelligence tests have a long history and have been used for decades, for example, the Stanford-Binet test or the Wechsler test. However, the vast majority of these tests are based on the classic linear test structure, in which all respondents receive all tasks (see, for example, a critical review by [5]). This understanding of the testing procedure is a legacy of the pre-computer era, in which blank testing was the only diagnostic procedure available [6] and has some significant limitations that affect the reliability of the data obtained [7] and increased time costs. Another problem with measuring IQ is that classical line-structured tests do not fully allow to measure respondent's intellectual progress [8], which is undoubtedly a critical limitation. Advances in modern psychometrics allow for avoiding the limitations of existing tools. However, as in any rapidly developing industry, at the moment, psychometrics does not offer ready-made and straightforward solutions and requires additional research. In our presentation we would like to discuss the strengths and weaknesses of the current approaches to intelligence measurement and highlight “points of growth” for creating a test in accordance with modern psychometrics. Whether it is possible to create the instrument that will use all achievements of modern psychometric and remain valid and practically oriented. What would be the possible limitations for such an instrument? The theoretical framework and study design to create and validate the original Russian comprehensive computer test for measuring the intellectual development in school-age children will be presented.

Keywords: Intelligence, psychometrics, psychological measurement, computerized adaptive testing, multistage testing

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Authors: Haiqin Zhou, Robin Irons

Abstract:

The introduction of hydrogen into local networks may, in many cases, require the initial operation of those systems on natural gas/hydrogen blends, either because of a lack of sufficient hydrogen to allow a 100% conversion or because existing infrastructure imposes limitations on the % hydrogen that can be burned before the end-use technologies are replaced. In many systems, the largest number of end-use technologies are small-scale but numerous appliances used for domestic and industrial heating and cooking. In such a scenario, it is important to understand exactly how much hydrogen can be introduced into these appliances before their performance becomes unacceptable and what imposes that limitation. This study seeks to explore a range of significantly higher hydrogen blends and a broad range of factors that might limit operability or environmental acceptability. We will present tests from a burner designed for space heating and optimized for natural gas as an increasing % of hydrogen blends (increasing from 25%) were burned and explore the range of parameters that might govern the acceptability of operation. These include gaseous emissions (particularly NOx and unburned carbon), temperature, flame length, stability and general operational acceptability. Results will show emissions, Temperature, and flame length as a function of thermal load and percentage of hydrogen in the blend. The relevant application and regulation will ultimately determine the acceptability of these values, so it is important to understand the full operational envelope of the burners in question through the sort of extensive parametric testing we have carried out. The present dataset should represent a useful data source for designers interested in exploring appliance operability. In addition to this, we present data on two factors that may be absolutes in determining allowable hydrogen percentages. The first of these is flame blowback. Our results show that, for our system, the threshold between acceptable and unacceptable performance lies between 60 and 65% mol% hydrogen. Another factor that may limit operation, and which would be important in domestic applications, is the acoustic performance of these burners. We will describe a range of operational conditions in which hydrogen blend burners produce a loud and invasive ‘screech’. It will be important for equipment designers and users to find ways to avoid this or mitigate it if performance is to be deemed acceptable.

Keywords: blends, operational, domestic appliances, future system operation.

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Authors: Yeasir Arafat Alve, Nazmun Nahar, Salma BeguM

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Introduction / Rationale: Caregivers of stroke survivors have experienced financial, emotional, physical and mental anxiety and have influence of family bonding and social customs, where 80% of caregivers were women and majority of the patients were cared for by immediate family members for example a spouse, son/daughter, son-in-law, daughter-in-law, siblings and they are significantly feel burden as a caregiver. In Bangladeshi context, there has a limitation of knowledge about the level of caregiver burden. This study could be suggested the health professional to focus on the care giving stress to provide a better support to them and also it will be advisable to provide equivalent services for caregivers and their families. Objectives: The study finds out the socio-demographic image of caregivers of stroke survivors in Bangladesh as well as discovers the level of burden of caregiver of stroke survivor in relation to general strain, isolation, disappointment, emotional involvement and environment. The study will find out the association between level of burden among caregivers and onset of stroke of survivors & duration of care giving. As well as to determine the association between level of burden among caregivers and caregiver’s age, gender, occupation and caregiver’s relationship with stroke survivors. Method / Approach: The study is a non experimental cross-sectional study design where 151 participants were selected through purposive comprehensive sampling. Data were selected from occupational therapy outdoor and stroke rehab unit, CRP (Savar & Mirpur) where using the Caregiver Burden Scale (a structured questionnaire) with face to face interview. Results: Most of the caregivers (78.8%) of stroke survivors faced moderate level of burden in general strain (37.7%), isolation (27.2%) but in case of disappointment (60.3%) feel higher burden and lower burden in emotional involvement (9.9%) and environment (0.7%). Caregiver burden level was significantly associated with caregivers’ age (P=0.006), sex (P=0.002), occupation (p= 0.04), relationship with stroke survivors (P=0.02), care giving duration (P=0.000), care giving hours (P=0.009), and onset of stroke (P=0.000) of stroke survivors. Conclusion: The study findings revealed that most of the caregivers faced moderate burden where no environmental burden for them, this is possibly in case of Bangladeshi culture where people hospitable. Through this study, it was also found that there is a possibility to have the higher burden. Finally, it is being also suggested that appropriate advice and support may preserve care giving which eventually enables the survivors to live a longer and more fulfilling life in the community.

Keywords: caregiver, level of caregiver burden, stroke survivor, stroke rehab unit

Procedia PDF Downloads 313

Authors: Mohamad Ammar Ayass, Natalya Griko, Victor Pashkov, Wanying Cao, Kevin Zhu, Jin Zhang, Lina Abi Mosleh

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Respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent for coronavirus disease 2019 (COVID-19). Early evidence pointed at the angiotensin-converting enzyme 2 (ACE-2) expressed on the epithelial cells of the lung as the main entry point of SARS-CoV-2 into the cells. The viral entry is mediated by the binding of the Receptor Binding Domain (RBD) of the spike protein that is expressed on the surface of the virus to the ACE-2 receptor. As the number of SARS-CoV-2 variants continues to increase, mutations arising in the RBD of SARS-CoV-2 may lead to the ineffectiveness of RBD targeted neutralizing antibodies. To address this limitation, the objective of this study is to develop a combination of aptamers that target different regions of the RBD, preventing the binding of the spike protein to ACE-2 receptor and subsequent viral entry and replication. A safe and innovative biomedical tool was developed to inhibit viral infection and reduce the harms of COVID-19. In the present study, DNA aptamers were developed against a recombinant trimer S protein using the Systematic Evolution of Ligands by Exponential enrichment (SELEX). Negative selection was introduced at round number 7 to select for aptamers that bind specifically to the RBD domain. A series of 9 aptamers (ADI2010, ADI2011, ADI201L, ADI203L, ADI205L, ADIR68, ADIR74, ADIR80, ADIR83) were selected and characterized with high binding affinity and specificity to the RBD of the spike protein. Aptamers (ADI25, ADI2009, ADI203L) were able to bind and pull down endogenous spike protein expressed on the surface of SARS-CoV-2 virus in COVID-19 positive patient samples and determined by liquid chromatography- tandem mass spectrometry analysis (LC-MS/MS). LC-MS/MS data confirmed that aptamers can bind to the RBD of the spike protein. Furthermore, results indicated that the combination of the 9 best aptamers inhibited the binding of the purified trimer spike protein to the ACE-2 receptor found on the surface of Vero E6 cells. In the same experiment, the combined aptamers displayed a better neutralizing effect than antibodies. The data suggests that the selected aptamers could be used in therapy to neutralize the effect of the SARS-CoV-2 virus by inhibiting the interaction between the RBD and ACE-2 receptor, preventing viral entry into target cells and therefore blocking viral replication.

Keywords: aptamer, ACE-2 receptor, binding inhibitor, COVID-19, spike protein, SARS-CoV-2, treatment

Procedia PDF Downloads 185