Search results for: bridge deterioration modelling
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3076

Search results for: bridge deterioration modelling

2566 Modelling of Atomic Force Microscopic Nano Robot's Friction Force on Rough Surfaces

Authors: M. Kharazmi, M. Zakeri, M. Packirisamy, J. Faraji

Abstract:

Micro/Nanorobotics or manipulation of nanoparticles by Atomic Force Microscopic (AFM) is one of the most important solutions for controlling the movement of atoms, particles and micro/nano metrics components and assembling of them to design micro/nano-meter tools. Accurate modelling of manipulation requires identification of forces and mechanical knowledge in the Nanoscale which are different from macro world. Due to the importance of the adhesion forces and the interaction of surfaces at the nanoscale several friction models were presented. In this research, friction and normal forces that are applied on the AFM by using of the dynamic bending-torsion model of AFM are obtained based on Hurtado-Kim friction model (HK), Johnson-Kendall-Robert contact model (JKR) and Greenwood-Williamson roughness model (GW). Finally, the effect of standard deviation of asperities height on the normal load, friction force and friction coefficient are studied.

Keywords: atomic force microscopy, contact model, friction coefficient, Greenwood-Williamson model

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2565 Pragmatic Language Characteristics of Individuals with Asperger Syndrome: Systematic Literature Review and Meta-analysis

Authors: Sadeq Alyaari, Muhammad Alkhunayn, Montaha Al Yaari, Ayman Al Yaari, Ayah Al Yaari, Adham Al Yaari, Sajedah Al Yaari, Fatehi Eissa

Abstract:

Introduction. The purpose of this Systematic Literature Review and Meta-analysis ((SLR & Meta-analysis) was to examine the differences between Asperger syndrome (AS) individuals and typically developing and achieving individuals (TD) regarding language competence and how these differences related to AS individuals’ age and the significance such differences add to our knowledge of understanding their language performance as issues that are still underdiagnosed and ill-treated entities. Methods. The study followed SLR & Meta-analysis protocol and was armed with data of 456 AS subjects and controls (231 and 225, respectively) abstracted from 14 studies that have been collected from different electronic bibliographic databases including web of science, Scopus, EMBASE, Cochrane library, PubMed, PsycInfo and google scholar along with unpublished literature. Results. Outlined results show deterioration in language competence of AS subjects in comparison to TD controls. Such deterioration impairs conversational implicature more than it does conventional maxims of AS individuals’ pragmatic language and has no relationship with their age. Results also show that the difference in intelligence features of the mental reality in the language competence becomes smaller with increasing age and that the difference in representational content features becomes larger. Conclusions. These findings help experts in the field not only predict pragmatic language impairments in AS individuals but also enable AS individuals themselves to decode and/or interpret speech inputs; therefore, perceive the world around them and interact with their community members. Outcomes should be considered to lay out a path for further exploration of genetics, etiology, and response to treatment of all these premises that are currently unsearched in AS individuals.

Keywords: pragmatic language characteristics, language competence, mental faculty, mental reality, features, language performance, pragmatics, conventional maxims

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2564 Development of an Automatic Calibration Framework for Hydrologic Modelling Using Approximate Bayesian Computation

Authors: A. Chowdhury, P. Egodawatta, J. M. McGree, A. Goonetilleke

Abstract:

Hydrologic models are increasingly used as tools to predict stormwater quantity and quality from urban catchments. However, due to a range of practical issues, most models produce gross errors in simulating complex hydraulic and hydrologic systems. Difficulty in finding a robust approach for model calibration is one of the main issues. Though automatic calibration techniques are available, they are rarely used in common commercial hydraulic and hydrologic modelling software e.g. MIKE URBAN. This is partly due to the need for a large number of parameters and large datasets in the calibration process. To overcome this practical issue, a framework for automatic calibration of a hydrologic model was developed in R platform and presented in this paper. The model was developed based on the time-area conceptualization. Four calibration parameters, including initial loss, reduction factor, time of concentration and time-lag were considered as the primary set of parameters. Using these parameters, automatic calibration was performed using Approximate Bayesian Computation (ABC). ABC is a simulation-based technique for performing Bayesian inference when the likelihood is intractable or computationally expensive to compute. To test the performance and usefulness, the technique was used to simulate three small catchments in Gold Coast. For comparison, simulation outcomes from the same three catchments using commercial modelling software, MIKE URBAN were used. The graphical comparison shows strong agreement of MIKE URBAN result within the upper and lower 95% credible intervals of posterior predictions as obtained via ABC. Statistical validation for posterior predictions of runoff result using coefficient of determination (CD), root mean square error (RMSE) and maximum error (ME) was found reasonable for three study catchments. The main benefit of using ABC over MIKE URBAN is that ABC provides a posterior distribution for runoff flow prediction, and therefore associated uncertainty in predictions can be obtained. In contrast, MIKE URBAN just provides a point estimate. Based on the results of the analysis, it appears as though ABC the developed framework performs well for automatic calibration.

Keywords: automatic calibration framework, approximate bayesian computation, hydrologic and hydraulic modelling, MIKE URBAN software, R platform

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2563 Crude Oil Electrostatic Mathematical Modelling on an Existing Industrial Plant

Authors: Fatemeh Yazdanmehr, Iulian Nistor

Abstract:

The scope of the current study is the prediction of water separation in a two-stage industrial crude oil desalting plant. This research study was focused on developing a desalting operation in an existing production unit of one Iranian heavy oil field with 75 MBPD capacity. Because of some operational issues, such as oil dehydration at high temperatures, the optimization of the desalter operational parameters was essential. The mathematical desalting is modeled based on the population balance method. The existing operational data is used for tuning and validation of the accuracy of the modeling. The inlet oil temperature to desalter used was decreased from 110°C to 80°C, and the desalted electrical field was increased from 0.75 kv to 2.5 kv. The proposed condition for the desalter also meets the water oil specification. Based on these conditions of desalter, the oil recovery is increased by 574 BBL/D, and the gas flaring decrease by 2.8 MMSCF/D. Depending on the oil price, the additional production of oil can increase the annual income by about $15 MM and reduces greenhouse gas production caused by gas flaring.

Keywords: desalter, demulsification, modelling, water-oil separation, crude oil emulsion

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2562 Customer Data Analysis Model Using Business Intelligence Tools in Telecommunication Companies

Authors: Monica Lia

Abstract:

This article presents a customer data analysis model using business intelligence tools for data modelling, transforming, data visualization and dynamic reports building. Economic organizational customer’s analysis is made based on the information from the transactional systems of the organization. The paper presents how to develop the data model starting for the data that companies have inside their own operational systems. The owned data can be transformed into useful information about customers using business intelligence tool. For a mature market, knowing the information inside the data and making forecast for strategic decision become more important. Business Intelligence tools are used in business organization as support for decision-making.

Keywords: customer analysis, business intelligence, data warehouse, data mining, decisions, self-service reports, interactive visual analysis, and dynamic dashboards, use cases diagram, process modelling, logical data model, data mart, ETL, star schema, OLAP, data universes

Procedia PDF Downloads 413
2561 Text Analysis to Support Structuring and Modelling a Public Policy Problem-Outline of an Algorithm to Extract Inferences from Textual Data

Authors: Claudia Ehrentraut, Osama Ibrahim, Hercules Dalianis

Abstract:

Policy making situations are real-world problems that exhibit complexity in that they are composed of many interrelated problems and issues. To be effective, policies must holistically address the complexity of the situation rather than propose solutions to single problems. Formulating and understanding the situation and its complex dynamics, therefore, is a key to finding holistic solutions. Analysis of text based information on the policy problem, using Natural Language Processing (NLP) and Text analysis techniques, can support modelling of public policy problem situations in a more objective way based on domain experts knowledge and scientific evidence. The objective behind this study is to support modelling of public policy problem situations, using text analysis of verbal descriptions of the problem. We propose a formal methodology for analysis of qualitative data from multiple information sources on a policy problem to construct a causal diagram of the problem. The analysis process aims at identifying key variables, linking them by cause-effect relationships and mapping that structure into a graphical representation that is adequate for designing action alternatives, i.e., policy options. This study describes the outline of an algorithm used to automate the initial step of a larger methodological approach, which is so far done manually. In this initial step, inferences about key variables and their interrelationships are extracted from textual data to support a better problem structuring. A small prototype for this step is also presented.

Keywords: public policy, problem structuring, qualitative analysis, natural language processing, algorithm, inference extraction

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2560 Improving Traditional Methods of Handling Fish from Integrated Pond Culture Systems in Monai Village, New Bussa, Nigeria

Authors: Olokor O. Julius, Ngwu E. Onyebuchi, Ajani K. Emmanuel, Omitoyin O. Bamidele, Olokor O. Linda, Akomas Stella

Abstract:

The study assessed the quality changes of Clarias gariepenus obtained from integrated culture systems (rice, poultry and fish) which were displayed at 31-33oC average daily temperature on the traditional market table used by local fish farmers to sell fish harvested from their ponds and those on an improved table designed for this study. Unlike the conventional table, the improved table was screened against flies and indiscriminate touch by customers. The fishes were displayed on both tables for 9 hours and quality attributes were monitored hourly by trained panelists. For C. gariepinus, the gills, and intestine recorded faster deterioration starting from the fourth and fifth hours while those on the improved table were prolonged by one hour. Scores for skin brightness and texture did not indicate quality deterioration throughout the display period. However, at the end of the storage time, samples on the improved table recorded 1.5 x 104 cfu/g while samples in unscreened table recorded 3.7 x 10 7 cfu/g. The study shows how simple modifications of a traditional practice can help extend keeping qualities of farmed fish, reduce health hazards in local communities where there is no electricity to preserve fish in whatever form despite a boom in aquaculture. Monai community has a fish farm estate of over 200 small holder farmers with annual output capacity of over $10 million dollars. The simple improvement made to farmers practice in this study is to ensure Community hygiene and boost income of peasant fish farmers by improving the market quality of their products.

Keywords: fish spoilage, improved handling, income generation, retail table

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2559 Modelling of Pipe Jacked Twin Tunnels in a Very Soft Clay

Authors: Hojjat Mohammadi, Randall Divito, Gary J. E. Kramer

Abstract:

Tunnelling and pipe jacking in very soft soils (fat clays), even with an Earth Pressure Balance tunnel boring machine (EPBM), can cause large ground displacements. In this study, the short-term and long-term ground and tunnel response is predicted for twin, pipe-jacked EPBM 3 meter diameter tunnels with a narrow pillar width. Initial modelling indicated complete closure of the annulus gap at the tail shield onto the centrifugally cast, glass-fiber-reinforced, polymer mortar jacking pipe (FRP). Numerical modelling was employed to simulate the excavation and support installation sequence, examine the ground response during excavation, confirm the adequacy of the pillar width and check the structural adequacy of the installed pipe. In the numerical models, Mohr-Coulomb constitutive model with the effect of unloading was adopted for the fat clays, while for the bedrock layer, the generalized Hoek-Brown was employed. The numerical models considered explicit excavation sequences and different levels of ground convergence prior to support installation. The well-studied excavation sequences made the analysis possible for this study on a very soft clay, otherwise, obtaining the convergency in the numerical analysis would be impossible. The predicted results indicate that the ground displacements around the tunnel and its effect on the pipe would be acceptable despite predictions of large zones of plastic behaviour around the tunnels and within the entire pillar between them due to excavation-induced ground movements.

Keywords: finite element modeling (FEM), pipe-jacked tunneling, very soft clay, EPBM

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2558 Design and Optimization of a Customized External Fixation Device for Lower Limb Injuries

Authors: Mohammed S. Alqahtani, Paulo J. Bartolo

Abstract:

External fixation is a common technique for the treatment and stabilization of bone fractures. Different designs have been proposed by companies and research groups, but all of them present limitations such as high weight, not comfortable to use, and not customized to individual patients. This paper proposes a lightweight customized external fixator, overcoming some of these limitations. External fixators are designed using a set of techniques such as medical imaging, CAD modelling, finite element analysis, and full factorial design of experiments. Key design parameters are discussed, and the optimal set of parameters is used to design the final external fixator. Numerical simulations are used to validate design concepts. Results present an optimal external fixation design with weight reduction of 13% without compromising its stiffness and structural integrity. External fixators are also designed to be additively manufactured, allowing to develop a strategy for personalization.

Keywords: computer-aided design modelling, external fixation, finite element analysis, full factorial, personalization

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2557 Building Information Modelling for Construction Delay Management

Authors: Essa Alenazi, Zulfikar Adamu

Abstract:

The Kingdom of Saudi Arabia (KSA) is not an exception in relying on the growth of its construction industry to support rapid population growth. However, its need for infrastructure development is constrained by low productivity levels and cost overruns caused by factors such as delays to project completion. Delays in delivering a construction project are a global issue and while theories such as Optimism Bias have been used to explain such delays, in KSA, client-related causes of delays are also significant. The objective of this paper is to develop a framework-based approach to explore how the country’s construction industry can manage and reduce delays in construction projects through building information modelling (BIM) in order to mitigate the cost consequences of such delays.  It comprehensively and systematically reviewed the global literature on the subject and identified gaps, critical delay factors and the specific benefits that BIM can deliver for the delay management.  A case study comprising of nine hospital projects that have experienced delay and cost overruns was also carried out. Five critical delay factors related to the clients were identified as candidates that can be mitigated through BIM’s benefits. These factors are: Ineffective planning and scheduling of the project; changes during construction by the client; delay in progress payment; slowness in decision making by the client; and poor communication between clients and other stakeholders. In addition, data from the case study projects strongly suggest that optimism bias is present in many of the hospital projects. Further validation via key stakeholder interviews and documentations are planned.

Keywords: building information modelling (BIM), clients perspective, delay management, optimism bias, public sector projects

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2556 Study on Comparison Between Acoustic Emission Behavior and Strain on Concrete Surface During Rebar Corrosion in Reinforced Concrete

Authors: Ejazulhaq Rahimi

Abstract:

The development of techniques evaluating deterioration on concrete structures is vital for structural health monitoring (SHM). One of the main reasons for reinforced concrete structure's deterioration is the corroding of embedded rebars. It is a natural process that begins when the rebar starts to rust. It occurs when the protective layer on the rebar is destroyed. The rebar in concrete is usually protected against corrosion by the high pH of the surrounding cement paste. However, there are chemicals that can destroy the protective layer, making it susceptible to corrosion. It is very destructive for the lifespan and durability of the concrete structure. Corrosion products which are 3 to 6 times voluminous than the rebar stress its surrounding concrete and lead to fracture as cracks even peeling off the cover concrete over the rebar. As is clear that concrete shows limit elastic behavior in its stress strain property, so corrosion product stresses can be detected as strains from the concrete surface. It means that surface strains have a relation with the situation and amount of corrosion products and related concrete fractures inside reinforced concrete. In this paper, a comparative study of surface strains due to corrosion products detected by strain gauges and acoustic emission (AE) testing under periodic accelerated corrosion in the salty environment with 3% NaCl is reported. From the results, three different stages of strains were clearly observed based on the type and rate of strains in each corrosion situation and related fracture types. AE parameters which mostly are related to fracture and their shapes, describe the same phases. It is confirmed that there is a great agreement to the result of each other and describes three phases as generation and expansion of corrosion products and initiation and propagation of corrosion-induced cracks, and surface cracks. In addition, the strain on the concrete surface was rapidly increased before the cracks arrived at the surface of the concrete.

Keywords: acoustic emission, monitoring, rebar corrosion, reinforced concrete, strain

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2555 Modelling and Simulation of Bioethanol Production from Food Waste Using CHEMCAD Software

Authors: Kgomotso Matobole, Noluzuko Monakali, Hilary Rutto, Tumisang Seodigeng

Abstract:

On a global scale, there is an alarming generation of food waste. Food waste is generated across the food supply chain. Worldwide urbanization, as well as global economic growth, have contributed to this amount of food waste the environment is receiving. Food waste normally ends on illegal dumping sites when not properly disposed, or disposed to landfills. This results in environmental pollution due to inadequate waste management practices. Food waste is rich in organic matter and highly biodegradable; hence, it can be utilized for the production of bioethanol, a type of biofuel. In so doing, alternative energy will be created, and the volumes of food waste will be reduced in the process. This results in food waste being seen as a precious commodity in energy generation instead of a pollutant. The main aim of the project was to simulate a biorefinery, using a software called CHEMCAD 7.12. The resulting purity of the ethanol from the simulation was 98.9%, with the feed ratio of 1: 2 for food waste and water. This was achieved by integrating necessary unit operations and optimisation of their operating conditions.

Keywords: fermentation, bioethanol, food waste, hydrolysis, simulation, modelling

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2554 Experimental and Numerical Studies of Droplet Formation

Authors: Khaled Al-Badani, James Ren, Lisa Li, David Allanson

Abstract:

Droplet formation is an important process in many engineering systems and manufacturing procedures, which includes welding, biotechnologies, 3D printing, biochemical, biomedical fields and many more. The volume and the characteristics of droplet formation are generally depended on various material properties, microfluidics and fluid mechanics considerations. Hence, a detailed investigation of this process, with the aid of numerical computational tools, are essential for future design optimization and process controls of many engineering systems. This will also improve the understanding of changes in the properties and the structures of materials, during the formation of the droplet, which is important for new material developments to achieve different functions, pending the requirements of the application. For example, the shape of the formed droplet is critical for the function of some final products, such as the welding nugget during Capacitor Discharge Welding process, or PLA 3D printing, etc. Although, most academic journals on droplet formation, focused on issued with material transfer rate, surface tension and residual stresses, the general emphasis on the characteristics of droplet shape has been overlooked. The proposed work for this project will examine theoretical methodologies, experimental techniques, and numerical modelling, using ANSYS FLUENT, to critically analyse and highlight optimization methods regarding the formation of pendant droplet. The project will also compare results from published data with experimental and numerical work, concerning the effects of key material parameters on the droplet shape. These effects include changes in heating/cooling rates, solidification/melting progression and separation/break-up times. From these tests, a set of objectives is prepared, with an intention of improving quality, stability and productivity in modelling metal welding and 3D printing.

Keywords: computer modelling, droplet formation, material distortion, materials forming, welding

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2553 Comparative Efficacy of Pomegranate Juice, Peel and Seed Extract in the Stabilization of Corn Oil under Accelerated Conditions

Authors: Zoi Konsoula

Abstract:

Antioxidant-rich extracts were prepared from pomegranate peels, seeds and juice using methanol and ethanol and their antioxidant activity was evaluated by the 1,1-diphenyl-2-picrylhydrazine (DPPH) radical scavenging and Ferric Reducing Antioxidant Power (FRAP) method. Both analytical methods indicated a higher antioxidant activity in extracts prepared from peels, which was comparable to that of butylated hydroxytoluene (BHT). Furthermore, the antioxidant activity was correlated to the phenolic and flavonoid content of the various extracts. The antioxidant effectiveness of the extracts was also assessed using corn oil as the oxidation substrate. More specifically, preheated corn oil samples stabilized with extracts at a concentration of 250 ppm, 500 ppm or 1,000 ppm were subjected to accelerated aging (100 oC, 10 days) and the extent of oxidative alteration was followed by the measurement of the peroxide, conjugated dienes and trienes, as well as p-aniside value. BHT at its legal limit (200 ppm) served as standard besides the control sample. Results from the different parameters were in agreement with each other suggesting that pomegranate extracts can stabilize corn oil effectively under accelerated conditions, at all concentrations tested. However, the magnitude of oil stabilization depended strongly on the amount of extract added and this was positively correlated with their phenolic content. Pomegranate peel extracts, which exhibited the highest not only phenolic and flavonoid content but also antioxidant activity, were more potent in inhibiting oxidative deterioration. Both methanolic and ethanolic peel extracts at a concentration of 500 ppm exerted a stabilizing effect comparable to that of BHT, while at a concentration of 1000 ppm they exhibited higher stabilization efficiency in comparison to BHT. Finally, heating oil samples resulted in a time dependent decrease in their antioxidant capacity. Samples containing peel extracts appeared to retain their antioxidant capacity for a longer period, indicating that these extracts contained active compounds that offered superior antioxidant protection to corn oil.

Keywords: antioxidant activity, corn oil, oxidative deterioration, pomegranate

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2552 The Impact of Steel Connections on the Fire Resistance of Composite Buildings

Authors: Shuyuan Lin, Zhaohui Huang, Mizi Fan

Abstract:

In the majority of previous research into modelling large scale composite floor subjected to fire, the beam-to-column and beam-to-beam connections were assumed to behave either as pinned or rigid for simplicity, and the vertical shear and axial tension failures of the connection were not taken into account. We have recently developed robust two-noded connection models for modeling endplate and partial endplate steel connections under fire conditions. The main objective of this research is to systematically investigate the impact of the connections of protected beams, on the tensile membrane actions of supported floor slabs in which the failures of the connections, such as, axial tension, vertical shear and bending are accounted for. The models developed have very good numerical stability under a static solver condition, and can be used for large scale modelling of composite buildings in fire.

Keywords: fire, steel structure, component-based model, beam-to-column connections

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2551 Psychological Well Being of Female Prisoners

Authors: Sujata Gupta Kedar, J. N. Tulika

Abstract:

Early researchers suggested that imprisonment had negative psychological and physical effects on its inmates, leading to psychological deterioration. The term “prisons” in the Consensus Statement of WHO is intended to denote, as those institutions which hold people who have been sentenced to a period of imprisonment by the courts for offences against the law. Thus “prisons” if local circumstances justify it, may also be taken to include secure institutions holding on a compulsory basis on any of the following categories of people: remand prisoners; civil prisoners; juvenile detainees; immigration detainees; some categories of mentally disordered patients; asylum seekers; refugees; people detained pending expulsion, deportation, exile, exclusion or any other form of compulsory transfer to other countries or areas of the country; people detained in police cells; and any other compulsorily detained group. Prisons are aimed to cure the criminal and their behavior but their records are not encouraging. Instead the imprisonment affects all prisoners in different way. From withstanding the shock of entry to the new culture, which is very different from their own, prisoners must try to determine how to spend the time in prison, since the hours appears to be endless in prisons. There is also the fear of deterioration. This article aims to provide an overview of the psychological well being of female prisoners in the prison environment in five areas- satisfaction, efficiency, sociability, mental health and interpersonal relations. Research was done on two different types of imprisonment- under trial prisoner and convict. Total sample included 22 female prisoners of Nagaon Special Jail of Assam. The instrument used for the study was based on Psychological Well Being Scale. Statistical analysis was done with t-test and one way anova test. The result demonstrated that there is no significant difference in the psychological wellbeing of female prisoners in the prison and that there is no significant difference in the psychological well being of different types of female prisoners involved in different crimes but there is significant difference in the mental health of the female prisoners in prison.

Keywords: psychological effect, female prisoners, prison, well being of prisoners

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2550 Numerical Solution of a Mathematical Model of Vortex Using Projection Method: Applications to Tornado Dynamics

Authors: Jagdish Prasad Maurya, Sanjay Kumar Pandey

Abstract:

Inadequate understanding of the complex nature of flow features in tornado vortex is a major problem in modelling tornadoes. Tornadoes are violent atmospheric phenomenon that appear all over the world. Modelling tornadoes aim to reduce the loss of the human lives and material damage caused by the tornadoes. Dynamics of tornado is investigated by a numerical technique, the improved version of the projection method. In this paper, authors solve the problem for axisymmetric tornado vortex by the said method that uses a finite difference approach for getting an accurate and stable solution. The conclusions drawn are that large radial inflow velocity occurs near the ground that leads to increase the tangential velocity. The increased velocity phenomenon occurs close to the boundary and absolute maximum wind is obtained near the vortex core. The results validate previous numerical and theoretical models.

Keywords: computational fluid dynamics, mathematical model, Navier-Stokes equations, tornado

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2549 Modelling and Analysis of Shear Banding in Flow of Complex Fluids

Authors: T. Chinyoka

Abstract:

We present the Johnson-Segalman constitutive model to capture certain fluid flow phenomena that has been experimentally observed in the flow of complex polymeric fluids. In particular, experimentally observed phenomena such as shear banding, spurt and slip are explored and/or explained in terms of the non-monotonic shear-stress versus shear-rate relationships. We also explore the effects of the inclusion of physical flow aspects such as wall porosity on shear banding. We similarly also explore the effects of the inclusion of mathematical modelling aspects such as stress diffusion into the stress constitutive models in order to predict shear-stress (or shear-rate) paths. We employ semi-implicit finite difference methods for all the computational solution procedures.

Keywords: Johnson-Segalman model, diffusive Johnson-Segalman model, shear banding, finite difference methods, complex fluid flow

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2548 Effects of Oral L-Carnitine on Liver Functions after Trans arterial Chemoembolization in Hepatocellular Carcinoma Patients

Authors: Ali Kassem, Aly Taha, Abeer Hassan, Kazuhide Higuchi

Abstract:

Introduction: Trans arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) is usually followed by hepatic dysfunction that limits its efficacy. L-carnitine is recently studied as hepatoprotective agent. Our aim is to evaluate the L-carnitine effects against the deterioration of liver functions after TACE. Method: 53 patients with intermediate stage HCC were assigned into two groups; L-carnitine group (26 patients) who received L-carnitine 300 mg tablet twice daily from 2 weeks before to 12 weeks after TACE and control group (27 patients) without L-carnitine therapy. 28 of studied patients received branched chain amino acids granules. Results: There were significant differences between L-carnitine Vs. control group in mean serum albumin change from baseline to 1 week and 4 weeks after TACE (p < 0.05). L-Carnitine maintained Child-Pugh score at 1 week after TACE and exhibited improvement at 4 weeks after TACE (p < 0.01 Vs 1 week after TACE). Control group has significant Child-Pugh score deterioration from baseline to 1 week after TACE (p < 0.05) and 12 weeks after TACE (p < 0.05). There were significant differences between L-carnitine and control groups in mean Child-Pugh score change from baseline to 4 weeks (p < 0.05) and 12 weeks after TACE (p < 0.05). L-carnitine displayed improvement in (PT) from baseline to 1 week, 4 w (p < 0.05) and 12 weeks after TACE. PT in control group declined less than baseline along all follow up intervals. Total bilirubin in L-carnitine group decreased at 1 week post TACE while in control group, it significantly increased at 1 week (p = 0.01). ALT and C-reactive protein elevation were suppressed at 1 week after TACE in Lcarnitine group. The hepatoprotective effects of L-carnitine were enhanced by concomitant use of branched chain amino acids. Conclusion: L-carnitine and BCAA combination therapy offer a novel supportive strategy after TACE in HCC patients.

Keywords: hepatocellular carcinoma, L-carnitine, liver functions , trans-arterial embolization

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2547 Aspen Plus Simulation of Saponification of Ethyl Acetate in the Presence of Sodium Hydroxide in a Plug Flow Reactor

Authors: U. P. L. Wijayarathne, K. C. Wasalathilake

Abstract:

This work presents the modelling and simulation of saponification of ethyl acetate in the presence of sodium hydroxide in a plug flow reactor using Aspen Plus simulation software. Plug flow reactors are widely used in the industry due to the non-mixing property. The use of plug flow reactors becomes significant when there is a need for continuous large scale reaction or fast reaction. Plug flow reactors have a high volumetric unit conversion as the occurrence for side reactions is minimum. In this research Aspen Plus V8.0 has been successfully used to simulate the plug flow reactor. In order to simulate the process as accurately as possible HYSYS Peng-Robinson EOS package was used as the property method. The results obtained from the simulation were verified by the experiment carried out in the EDIBON plug flow reactor module. The correlation coefficient (r2) was 0.98 and it proved that simulation results satisfactorily fit for the experimental model. The developed model can be used as a guide for understanding the reaction kinetics of a plug flow reactor.

Keywords: aspen plus, modelling, plug flow reactor, simulation

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2546 Visco-Acoustic Full Wave Inversion in the Frequency Domain with Mixed Grids

Authors: Sheryl Avendaño, Miguel Ospina, Hebert Montegranario

Abstract:

Full Wave Inversion (FWI) is a variant of seismic tomography for obtaining velocity profiles by an optimization process that combine forward modelling (or solution of wave equation) with the misfit between synthetic and observed data. In this research we are modelling wave propagation in a visco-acoustic medium in the frequency domain. We apply finite differences for the numerical solution of the wave equation with a mix between usual and rotated grids, where density depends on velocity and there exists a damping function associated to a linear dissipative medium. The velocity profiles are obtained from an initial one and the data have been modeled for a frequency range 0-120 Hz. By an iterative procedure we obtain an estimated velocity profile in which are detailed the remarkable features of the velocity profile from which synthetic data were generated showing promising results for our method.

Keywords: seismic inversion, full wave inversion, visco acoustic wave equation, finite diffrence methods

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2545 Predicting the Potential Geographical Distribution of the Banana Aphid (Pentalonia nigronervosa) as Vector of Banana Bunchy Top Virus Using Diva-GIS

Authors: Marilyn Painagan

Abstract:

This study was conducted to predict the potential geographical distribution of the banana aphid (Pentalonia negronervosa) in North Cotabato through climate envelope approach of DIVA-GIS, a software for analyzing the distribution of organisms to elucidate geographic and ecological patterns. A WorldClim database that was based on weather conditions recorded last 1950 to 2000 with a spatial resolution of approximately 1x1 km. was used in the bioclimatic modelling, this database includes temperature, precipitation, evapotranspiration and bioclimatic variables which was measured at many different locations, a bioclimatic modelling was done in the study. The study revealed that the western part of Magpet and Arakan and the municipality of Antipas are at high potential risk of occurrence of banana aphid while it is not likely to occur in the municipalities of Aleosan, Midsayap, Pikit, M’lang and Tulunan. The result of this study can help developed strategies for monitoring and managing this serious pest of banana and to prepare a mitigation measures on those areas that are potential for future infestation.

Keywords: banana aphid, bioclimatic model, bunchy top, climatic envelope approach

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2544 Addressing Water Scarcity in Gomti Nagar, Lucknow, India: Assessing the Effectiveness of Rooftop Rainwater Harvesting Systems

Authors: Rajkumar Ghosh

Abstract:

Water scarcity is a significant challenge in urban areas, even in smart cities (Lucknow, Bangalore, Jaipur, etc.) where efficient resource management is prioritized. The depletion of groundwater resources in Gomti Nagar, Lucknow, Uttar Pradesh, India is particularly severe, posing a significant challenge for sustainable development in the region. This study focuses on addressing the water shortage by investigating the effectiveness of rooftop rainwater harvesting systems (RTRWHs) as a sustainable approach to bridge the gap between groundwater recharge and extraction. The aim of this study is to assess the effectiveness of RTRWHs in reducing aquifer depletion and addressing the water scarcity issue in the Gomti Nagar region. The research methodology involves the utilization of RTRWHs as the primary method for collecting rainwater. RTRWHs will be implemented in residential and commercial buildings to maximize the collection of rainwater. Data for this study were collected through various sources such as government reports, surveys, and existing groundwater abstraction patterns. Statistical analysis and modelling techniques were employed to assess the current water situation, groundwater depletion rate, and the potential impact of implementing RTRWHs. The study reveals that the installation of RTRWHs in the Gomti Nagar region has a positive impact on addressing the water scarcity issue. Currently, RTRWHs cover only a small percentage of the total rainfall collected in the region. However, when RTRWHs are installed in all buildings, their influence on increasing water availability and reducing aquifer depletion will be significantly greater. The study also highlights the significant water imbalance in the region, emphasizing the urgent need for sustainable water management practices. This research contributes to the theoretical understanding of sustainable water management systems in smart cities. By highlighting the effectiveness of RTRWHs in reducing aquifer depletion, it emphasizes the importance of implementing such systems in urban areas. Data for this study were collected through various sources such as government reports, surveys, and existing groundwater abstraction patterns. The collected data were then analysed using statistical analysis and modelling techniques to assess the current water situation, groundwater depletion rate, and the potential impact of implementing RTRWHs. The findings of this study demonstrate that the implementation of RTRWHs can effectively mitigate the water scarcity crisis in Gomti Nagar. By reducing aquifer depletion and bridging the gap between groundwater recharge and extraction, RTRWHs offer a sustainable solution to the region's water scarcity challenges. Widespread adoption of RTRWHs in all buildings and integration into urban planning and development processes are crucial for efficient water management in smart cities like Gomti Nagar. These findings can serve as a basis for policymakers, urban planners, and developers to prioritize and incentivize the installation of RTRWHs as a potential solution to the water shortage crisis.

Keywords: water scarcity, urban areas, smart cities, resource management, groundwater depletion, rooftop rainwater harvesting systems, sustainable development, sustainable water management, mitigating water scarcity

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2543 A Case of Iatrogenic Esophageal Perforation in an Extremely Low Birth Weight Neonate

Authors: Ya-Ching Fu, An-Kuo Chou, Boon-Fatt Tan, Chi-Nien Chen, Wen-Chien Yang, Pou-Leng Cheong

Abstract:

Blind oro-/naso-pharyngeal suction and feeding tube placement are very common practices in neonatal intensive care unit. Though esophageal perforation is a rare complication of these instrumentations, its prevalence is highest in extremely premature neonates. Due to its association with significant morbidity (including respiratory deterioration, pneumothorax, and sepsis) and even mortality, it is an important issue to prevent this iatrogenic complication in the field of premature care. We demonstrate an esophageal perforation in an extreme-low-birth-weight neonate after oro-gastric tube placement. This female baby weighing 680 grams was delivered by caesarean section at 25 weeks of gestational age. She initially received oro-tracheal intubation with mechanical ventilation which was smoothly weaned to non-invasive positive-pressure ventilation at 7-day-old. However, after insertion of a 5-French oro-gastric tube, the baby’s condition suddenly worsened with apnea requiring mechanical ventilation. Her chest radiogram showed the oro-gastric tube in right pleural space, and thus another oro-gastric tube was replaced, and its position was radiographically confirmed. The malpositioned tube was then removed. The baby received 2-week course of intravenous antibiotics for her esophageal perforation. Feeding was then reintroduced and increased to full feeds in a smooth course. She was discharged at 107-day-old. Esophageal perforation in newborn is very rare. Sudden respiratory deterioration in a neonate after naso-/oro-gastric tube placement should alarm us to consider esophageal perforation, and further radiological investigation is required for the diagnosis. Tube materials, patient condition, and age are major risk factors of esophageal perforation. The use of softer tube material, such as silicone, in extreme premature baby might prevent this fetal complication.

Keywords: esophageal perforation, preterm, newborn, feeding tube

Procedia PDF Downloads 251
2542 Budgetary Performance Model for Managing Pavement Maintenance

Authors: Vivek Hokam, Vishrut Landge

Abstract:

An ideal maintenance program for an industrial road network is one that would maintain all sections at a sufficiently high level of functional and structural conditions. However, due to various constraints such as budget, manpower and equipment, it is not possible to carry out maintenance on all the needy industrial road sections within a given planning period. A rational and systematic priority scheme needs to be employed to select and schedule industrial road sections for maintenance. Priority analysis is a multi-criteria process that determines the best ranking list of sections for maintenance based on several factors. In priority setting, difficult decisions are required to be made for selection of sections for maintenance. It is more important to repair a section with poor functional conditions which includes uncomfortable ride etc. or poor structural conditions i.e. sections those are in danger of becoming structurally unsound. It would seem therefore that any rational priority setting approach must consider the relative importance of functional and structural condition of the section. The maintenance priority index and pavement performance models tend to focus mainly on the pavement condition, traffic criteria etc. There is a need to develop the model which is suitably used with respect to limited budget provisions for maintenance of pavement. Linear programming is one of the most popular and widely used quantitative techniques. A linear programming model provides an efficient method for determining an optimal decision chosen from a large number of possible decisions. The optimum decision is one that meets a specified objective of management, subject to various constraints and restrictions. The objective is mainly minimization of maintenance cost of roads in industrial area. In order to determine the objective function for analysis of distress model it is necessary to fix the realistic data into a formulation. Each type of repair is to be quantified in a number of stretches by considering 1000 m as one stretch. A stretch considered under study is having 3750 m length. The quantity has to be put into an objective function for maximizing the number of repairs in a stretch related to quantity. The distress observed in this stretch are potholes, surface cracks, rutting and ravelling. The distress data is measured manually by observing each distress level on a stretch of 1000 m. The maintenance and rehabilitation measured that are followed currently are based on subjective judgments. Hence, there is a need to adopt a scientific approach in order to effectively use the limited resources. It is also necessary to determine the pavement performance and deterioration prediction relationship with more accurate and economic benefits of road networks with respect to vehicle operating cost. The infrastructure of road network should have best results expected from available funds. In this paper objective function for distress model is determined by linear programming and deterioration model considering overloading is discussed.

Keywords: budget, maintenance, deterioration, priority

Procedia PDF Downloads 185
2541 Excel-VBA as Modelling Platform for Thermodynamic Optimisation of an R290/R600a Cascade Refrigeration System

Authors: M. M. El-Awad

Abstract:

The availability of computers and educational software nowadays helps engineering students acquire better understanding of engineering principles and their applications. With these facilities, students can perform sensitivity and optimisation analyses which were not possible in the past by using slide-rules and hand calculators. Standard textbooks in engineering thermodynamics also use software such as Engineering Equation Solver (EES) and Interactive Thermodynamics (IT) for solving calculation-intensive and design problems. Unfortunately, engineering students in most developing countries do not have access to such applications which are protected by intellectual-property rights. This paper shows how Microsoft ExcelTM and VBA (Visual Basic for Applications), which are normally distributed with personal computers and laptops, can be used as an alternative modelling platform for thermodynamic analyses and optimisation. The paper describes the VBA user-defined-functions developed for determining the refrigerants properties with Excel. For illustration, the combination is used to model and optimise the intermediate temperature for a propane/iso-butane cascade refrigeration system.

Keywords: thermodynamic optimisation, engineering education, excel, VBA, cascade refrigeration system

Procedia PDF Downloads 407
2540 Piezoelectric Approach on Harvesting Acoustic Energy

Authors: Khin Fai Chen, Jee-Hou Ho, Eng Hwa Yap

Abstract:

An acoustic micro-energy harvester (AMEH) is developed to convert wasted acoustical energy into useful electrical energy. AMEH is mathematically modeled using lumped element modelling (LEM) and Euler-Bernoulli beam (EBB) modelling. An experiment is designed to validate the mathematical model and assess the feasibility of AMEH. Comparison of theoretical and experimental data on critical parameter value such as Mm, Cms, dm and Ceb showed the variances are within 1% to 6%, which is reasonably acceptable. Hence, AMEH mathematical model is validated. Then, AMEH undergoes bandwidth tuning for performance optimization for further experimental work. The AMEH successfully produces 0.9 V⁄(m⁄s^2) and 1.79 μW⁄(m^2⁄s^4) at 60Hz and 400kΩ resistive load which only show variances about 7% compared to theoretical data. By integrating a capacitive load of 200µF, the discharge cycle time of AMEH is 1.8s and the usable energy bandwidth is available as low as 0.25g. At 1g and 60Hz resonance frequency, the averaged power output is about 2.2mW which fulfilled a range of wireless sensors and communication peripherals power requirements. Finally, the design for AMEH is assessed, validated and deemed as a feasible design.

Keywords: piezoelectric, acoustic, energy harvester

Procedia PDF Downloads 270
2539 Bridging the Gap between Teaching and Learning: A 3-S (Strength, Stamina, Speed) Model for Medical Education

Authors: Mangala. Sadasivan, Mary Hughes, Bryan Kelly

Abstract:

Medical Education must focus on bridging the gap between teaching and learning when training pre-clinical year students in skills needed to keep up with medical knowledge and to meet the demands of health care in the future. The authors were interested in showing that a 3-S Model (building strength, developing stamina, and increasing speed) using a bridged curriculum design helps connect teaching and learning and improves students’ retention of basic science and clinical knowledge. The authors designed three learning modules using the 3-S Model within a systems course in a pre-clerkship medical curriculum. Each module focused on a bridge (concept map) designed by the instructor for specific content delivered to students in the course. This with-in-subjects design study included 304 registered MSU osteopathic medical students (3 campuses) ranked by quintile based on previous coursework. The instructors used the bridge to create self-directed learning exercises (building strength) to help students master basic science content. Students were video coached on how to complete assignments, and given pre-tests and post-tests designed to give them control to assess and identify gaps in learning and strengthen connections. The instructor who designed the modules also used video lectures to help students master clinical concepts and link them (building stamina) to previously learned material connected to the bridge. Boardstyle practice questions relevant to the modules were used to help students improve access (increasing speed) to stored content. Unit Examinations covering the content within modules and materials covered by other instructors teaching within the units served as outcome measures in this study. This data was then compared to each student’s performance on a final comprehensive exam and their COMLEX medical board examinations taken some time after the course. The authors used mean comparisons to evaluate students’ performances on module items (using 3-S Model) to non-module items on unit exams, final course exam and COMLEX medical board examination. The data shows that on average, students performed significantly better on module items compared to non-module items on exams 1 and 2. The module 3 exam was canceled due to a university shut down. The difference in mean scores (module verses non-module) items disappeared on the final comprehensive exam which was rescheduled once the university resumed session. Based on Quintile designation, the mean scores were higher for module items than non-module items and the difference in scores between items for Quintiles 1 and 2 were significantly better on exam 1 and the gap widened for all Quintile groups on exam 2 and disappeared in exam 3. Based on COMLEX performance, all students on average as a group, whether they Passed or Failed, performed better on Module items than non-module items in all three exams. The gap between scores of module items for students who passed COMLEX to those who failed was greater on Exam 1 (14.3) than on Exam 2 (7.5) and Exam 3 (10.2). Data shows the 3-S Model using a bridge effectively connects teaching and learning

Keywords: bridging gap, medical education, teaching and learning, model of learning

Procedia PDF Downloads 41
2538 Expounding on the Role of Sustainability Values (SVs) on Consumers’ Switching Intentions Regarding Disruptive 5G Technology in China

Authors: Sayed Kifayat Shah, Tang Zhongjun, Mohammad Ahmad, Sohaib Mostafa

Abstract:

This article investigates consumer’s intention to shift to 5G in the light of disruptive technology innovation. To switch from 4G (Existing) technology to 5G (Disruptive) technology requires not just economic benefits and costs but involves other values too, which aren't yet experienced in the framework of technology innovation. This study extended the valued adaptation (VAM) model by proposing the sustainability values (SVs) construct. The model was examined on data from 361 Chinese consumers using the partial least squares-based structural equation modelling (PLS-SEM) technique. The outcomes prove the significant correlation of sustainability values (SVs) which influences consumer’s switching intentions toward 5G disruptive technology. The findings of this research will be helpful to telecoms firms in developing consumer retention strategies. Some limitations and the importance of the research for scholars and managers are also discussed.

Keywords: value adaptation model (VAM), sustainability values (SVs), disruptive 5G technology, switching intentions (SI), partial least squares-based structural equation modelling (PLS-SEM)

Procedia PDF Downloads 126
2537 Online Learning Versus Face to Face Learning: A Sentiment Analysis on General Education Mathematics in the Modern World of University of San Carlos School of Arts and Sciences Students Using Natural Language Processing

Authors: Derek Brandon G. Yu, Clyde Vincent O. Pilapil, Christine F. Peña

Abstract:

College students of Cebu province have been indoors since March 2020, and a challenge encountered is the sudden shift from face to face to online learning and with the lack of empirical data on online learning on Higher Education Institutions (HEIs) in the Philippines. Sentiments on face to face and online learning will be collected from University of San Carlos (USC), School of Arts and Sciences (SAS) students regarding Mathematics in the Modern World (MMW), a General Education (GE) course. Natural Language Processing with machine learning algorithms will be used to classify the sentiments of the students. Results of the research study are the themes identified through topic modelling and the overall sentiments of the students in USC SAS

Keywords: natural language processing, online learning, sentiment analysis, topic modelling

Procedia PDF Downloads 222