Search results for: resonant column/torsional simple shear
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5063

Search results for: resonant column/torsional simple shear

2213 Numerical Investigation of the Effect of Number of Waves on Heat Transfer in a Wavy Wall Enclosure

Authors: Ali Reza Tahavvor, Saeed Hosseini, Afshin Karimzadeh Fard

Abstract:

In this paper the effect of wall waviness of side walls in a two-dimensional wavy enclosure is numerically investigated. Two vertical wavy walls and straight top wall are kept isothermal and the bottom wall temperature is higher and spatially varying with cosinusoidal temperature distribution. A computational code based on Finite-volume approach is used to solve governing equations and SIMPLE method is used for pressure velocity coupling. Test is performed for several different numbers of undulations. The Prandtl number was kept constant and the Ra number denotes that the flow is laminar. Temperature and velocity fields are determined. Therefore, according to the obtained results a correlation is proposed for average Nusselt number as a function of number of side wall waves. The results indicate that the Nusselt number is highly affected by number of waves and increasing it decreases the wavy walls Nusselt number; although the Nusselt number is not highly affected by surface waviness when the number of undulations is below one.

Keywords: cavity, natural convection, Nusselt number, wavy wall

Procedia PDF Downloads 460
2212 Application of Water Soluble Polymers in Chemical Enhanced Oil Recovery

Authors: M. Shahzad Kamal, Abdullah S. Sultan, Usamah A. Al-Mubaiyedh, Ibnelwaleed A. Hussein

Abstract:

Oil recovery from reservoirs using conventional oil recovery techniques like water flooding is less than 20%. Enhanced oil recovery (EOR) techniques are applied to recover additional oil. Surfactant-polymer flooding is a promising EOR technique used to recover residual oil from reservoirs. Water soluble polymers are used to increase the viscosity of displacing fluids. Surfactants increase the capillary number by reducing the interfacial tension between oil and displacing fluid. Hydrolyzed polyacrylamide (HPAM) is widely used in polymer flooding applications due to its low cost and other desirable properties. HPAM works well in low-temperature and low salinity-environment. In the presence of salts HPAM viscosity decrease due to charge screening effect and it can precipitate at high temperatures in the presence of salts. Various strategies have been adopted to extend the application of water soluble polymers to high-temperature high-salinity (HTHS) reservoir. These include addition of monomers to acrylamide chain that can protect it against thermal hydrolysis. In this work, rheological properties of various water soluble polymers were investigated to find out suitable polymer and surfactant-polymer systems for HTHS reservoirs. Polymer concentration ranged from 0.1 to 1 % (w/v). Effect of temperature, salinity and polymer concentration was investigated using both steady shear and dynamic measurements. Acrylamido tertiary butyl sulfonate based copolymer showed better performance under HTHS conditions compared to HPAM. Moreover, thermoviscosifying polymer showed excellent rheological properties and increase in the viscosity was observed with increase temperature. This property is highly desirable for EOR application.

Keywords: rheology, polyacrylamide, salinity, enhanced oil recovery, polymer flooding

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2211 The Study of Flood Resilient House in Ebo-Town

Authors: Alagie Salieu Nankey

Abstract:

Flood-resistant house is the key mechanism to withstand flood hazards in Ebo-Town. It emerged simple yet powerful way of mitigating flooding in the community of Ebo- Town. Even though there are different types of buildings, little is known yet how and why flood affects building severely. In this paper, we examine three different types of flood-resistant buildings that are suitable for Ebo Town. We gather content and contextual features from six (6) respondents and used this data set to identify factors that are significantly associated with the flood-resistant house. Moreover, we built a suitable design concept. We found that amongst all the theories studied in the literature study Slit or Elevated House is the most suitable building design in Ebo-Town and Pile foundation is the most appropriate foundation type in the study area. Amongst contextual features, local materials are the most economical materials for the proposed design. This research proposes a framework that explains the theoretical relationships between flood hazard zones and flood-resistant houses in Ebo Town. Moreover, this research informs the design of sense-making and analytics tools for the resistant house.

Keywords: flood-resistant, slit, flood hazard zone, pile foundation

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2210 Analytical Solution of Specific Energy Equation in Exponential Channels

Authors: Abdulrahman Abdulrahman

Abstract:

The specific energy equation has many applications in practical channels, such as exponential channels. In this paper, the governing equation of alternate depth ratio for exponential channels, in general, was investigated towards obtaining analytical solution for the alternate depth ratio in three exponential channel shapes, viz., rectangular, triangular, and parabolic channels. The alternate depth ratio for rectangular channels is quadratic; hence it is very simple to solve. While for parabolic and triangular channels, the alternate depth ratio is cubic and quartic equations, respectively, analytical solution for these equations may be achieved easily for a given Froud number. Different examples are solved to prove the efficiency of the proposed solution. Such analytical solution can be easily used in natural rivers and most of practical channels.

Keywords: alternate depth, analytical solution, specific energy, parabolic channel, rectangular channel, triangular channel, open channel flow

Procedia PDF Downloads 192
2209 Synthesis of Novel Organic Dyes Based on Indigo for Dye-Sensitized Solar Cells

Authors: M. Hosseinnejad, K. Gharanjig, S. Moradian

Abstract:

A novel metal free organic dyes based on indigo was prepared and used as sensitizers in dye-sensitized solar cells. The synthesized dye together with its corresponding intermediates were purified and characterized by analytical techniques. Such techniques confirmed the corresponding structures of dye and its intermediate and the yield of all the stages of dye preparation were calculated to be above 85%. Fluorometric analyses show fluorescence in the green region of the visible spectrum for dye. Oxidation potential measurements for dye ensured an energetically permissible and thermodynamically favourable charge transfer throughout the continuous cycle of photo-electric conversion. Finally, dye sensitized solar cells were fabricated in order to determine the photovoltaic behaviour and conversion efficiencies of dye. Such evaluations demonstrate rather medium conversion efficiencies of 2.33% for such simple structured synthesized dye. Such conversion efficiencies demonstrate the potentiality of future use of such dye structures in dye-sensitized solar cells with respect to low material costs, ease of molecular tailoring, high yields of reactions, high performance and ease of recyclability.

Keywords: conversion efficiency, Dye-sensitized solar cells, indigo, photonic material

Procedia PDF Downloads 364
2208 Alternate Dispute Resolution: Expeditious Justice

Authors: Uzma Fakhar, Osama Fakhar, Aamir Shafiq Ch

Abstract:

Methods of alternate dispute resolution (ADR) like conciliation, arbitration, mediation are the supplement to ensure inexpensive and expeditious justice in a country. Justice delayed has not only created chaos, but an element of rebellious behavior towards judiciary is being floated among people. Complexity of traditional judicial system and its diversity has created an overall coherence. Admittedly, In Pakistan the traditional judicial system has failed to achieve its goals which resulted in the backlog of cases pending in courts, resultantly even the critics of alternate dispute resolution agree to restore the spirit of expeditious justice by reforming the old Panchayat system. The Government is keen to enact certain laws and make amendments to facilitate the resolution of a dispute through a simple and faster ADR framework instead of a lengthy and exhausting complex trial in order to create proliferation and faith in alternate dispute resolution. This research highlights the value of ADR in a country like Pakistan for revival of the confidence of the people upon the judicial process and a useful judicial tool to reduce the pressure on the judiciary.

Keywords: alternate dispute resolution, development of law, expeditious justice, Pakistan

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2207 Microwave Accelerated Simultaneous Distillation –Extraction: Preparative Recovery of Volatiles from Food Products

Authors: Ferhat Mohamed, Boukhatem Mohamed Nadjib, Chemat Farid

Abstract:

Simultaneous distillation–extraction (SDE) is routinely used by analysts for sample preparation prior to gas chromatography analysis. In this work, a new process design and operation for microwave assisted simultaneous distillation – solvent extraction (MW-SDE) of volatile compounds was developed. Using the proposed method, isolation, extraction and concentration of volatile compounds can be carried out in a single step. To demonstrate its feasibility, MW-SDE was compared with the conventional technique, Simultaneous distillation–extraction (SDE), for gas chromatography-mass spectrometry (GC-MS) analysis of volatile compounds in a fresh orange juice and a dry spice “carvi seeds”. SDE method required long time (3 h) to isolate the volatile compounds, and large amount of organic solvent (200 mL of hexane) for further extraction, while MW-SDE needed little time (only 30 min) to prepare sample, and less amount of organic solvent (10 mL of hexane). These results show that MW-SDE–GC-MS is a simple, rapid and solvent-less method for determination of volatile compounds from aromatic plants.

Keywords: essential oil, extraction, distillation, carvi seeds

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2206 Development of Simple-To-Apply Biogas Kinetic Models for the Co-Digestion of Food Waste and Maize Husk

Authors: Owamah Hilary, O. C. Izinyon

Abstract:

Many existing biogas kinetic models are difficult to apply to substrates they were not developed for, as they are substrate specific. Biodegradability kinetic (BIK) model and maximum biogas production potential and stability assessment (MBPPSA) model were therefore developed in this study for the anaerobic co-digestion of food waste and maize husk. Biodegradability constant (k) was estimated as 0.11d-1 using the BIK model. The results of maximum biogas production potential (A) obtained using the MBPPSA model corresponded well with the results obtained using the popular but complex modified Gompertz model for digesters B-1, B-2, B-3, B-4, and B-5. The (If) value of MBPPSA model also showed that digesters B-3, B-4, and B-5 were stable, while B-1 and B-2 were unstable. Similar stability observation was also obtained using the modified Gompertz model. The MBPPSA model can therefore be used as alternative model for anaerobic digestion feasibility studies and plant design.

Keywords: biogas, inoculum, model development, stability assessment

Procedia PDF Downloads 417
2205 A Simplified, Fabrication-Friendly Acoustophoretic Model for Size Sensitive Particle Sorting

Authors: V. Karamzadeh, J. Adhvaryu, A. Chandrasekaran, M. Packirisamy

Abstract:

In Bulk Acoustic Wave (BAW) microfluidics, the throughput of particle sorting is dependent on the complex interplay between the geometric configuration of the channel, the size of the particles, and the properties of the fluid medium, which therefore calls for a detailed modeling and understanding of the fluid-particle interaction dynamics under an acoustic field, prior to designing the system. In this work, we propose a simplified Bulk acoustophoretic system that can be used for size dependent particle sorting. A Finite Element Method (FEM) based analytical model has been developed to study the dependence of particle sizes on channel parameters, and the sorting efficiency in a given fluid medium. Based on the results, the microfluidic system has been designed to take into account all the variables involved with the underlying physics, and has been fabricated using an additive manufacturing technique employing a commercial 3D printer, to generate a simple, cost-effective system that can be used for size sensitive particle sorting.

Keywords: 3D printing, 3D microfluidic chip, acoustophoresis, cell separation, MEMS (Microelectromechanical Systems), microfluidics

Procedia PDF Downloads 165
2204 Dynamic Analysis of Functionally Graded Nano Composite Pipe with PZT Layers Subjected to Moving Load

Authors: Morteza Raminnia

Abstract:

In this study, dynamic analysis of functionally graded nano-composite pipe reinforced by single-walled carbon nano-tubes (SWCNTs) with simply supported boundary condition subjected to moving mechanical loads is investigated. The material properties of functionally graded carbon nano tube-reinforced composites (FG-CNTRCs) are assumed to be graded in the thickness direction and are estimated through a micro-mechanical model. In this paper polymeric matrix considered as isotropic material and for the CNTRC, uniform distribution (UD) and three types of FG distribution patterns of SWCNT reinforcements are considered. The system equation of motion is derived by using Hamilton's principle under the assumptions of first order shear deformation theory (FSDT).The thin piezoelectric layers embedded on inner and outer surfaces of FG-CNTRC layer are acted as distributed sensor and actuator to control dynamic characteristics of the FG-CNTRC laminated pipe. The modal analysis technique and Newmark's integration method are used to calculate the displacement and dynamic stress of the pipe subjected to moving loads. The effects of various material distribution and velocity of moving loads on dynamic behavior of the pipe is presented. This present approach is validated by comparing the numerical results with the published numerical results in literature. The results show that the above-mentioned effects play very important role on dynamic behavior of the pipe .This present work shows that some meaningful results that which are interest to scientific and engineering community in the field of FGM nano-structures.

Keywords: nano-composite, functionally garded material, moving load, active control, PZT layers

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2203 Moving Beyond the Limits of Disability Inclusion: Using the Concept of Belonging Through Friendship to Improve the Outcome of the Social Model of Disability

Authors: Luke S. Carlos A. Thompson

Abstract:

The medical model of disability, though beneficial for the medical professional, is often exclusionary, restrictive and dehumanizing when applied to the lived experience of disability. As a result, a critique of this model was constructed called the social model of disability. Much of the language used to articulate the purpose behind the social model of disability can be summed up within the word inclusion. However, this essay asserts that inclusiveness is an incomplete aspiration. The social model, as it currently stands, does not aid in creating a society where those with impairments actually belong. Rather, the social model aids in lessening the visibility, or negative consequence of, difference. Therefore, the social model does not invite society to welcome those with physical and intellectual impairments. It simply aids society in ignoring the existence of impairment by removing explicit forms of exclusion. Rather than simple inclusion, then, this essay uses John Swinton’s concept of friendship and Jean Vanier’s understanding of belonging to better articulate the intended outcome of the social model—a society where everyone can belong.

Keywords: belong, community, differently-able, disability, exclusion, friendship, inclusion, normality

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2202 Cultural Tourism, The Gateway to Socioeconomic Development in Nigeria: Case Study on Osun State Nigeria

Authors: Osinubi Olufemi Bankole

Abstract:

Cultural tourism is an industry committed to making a low impact on the environment, locale culture, festival, etc. while helping to generate income and employment opportunities for the locale. Tourists who promote cultural tourism are sensitive to the cultural belief and norms that are gradually going into extinction and the rich cultural resources that abound in Nigeria. The paper focus on culture been a unique way of life of particular people that differentiates them from their neighbors. It examined the socioeconomic roles of cultural tourism to the development of Nigeria using Osun state as case study. The data collected were analyzed using simple percentage method, result shows that 35 respondents representing 87.5% agreed that cultural tourism has a significant role to play in the socioeconomic development of Nigeria. The study concluded that cultural tourism is an important aspect of the nation’s economic sector that should be given adequate consideration for economic sustainability. The researcher recommended that various investment opportunities abound in the nation’s cultural resources if well developed and maintained.

Keywords: culture, development, industry, tourism

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2201 Simple Multipath Compensation for Frequency Modulated Signals: A Case of Radio Frequency vs. Quadrature Baseband

Authors: Lusungu Ndovi

Abstract:

Radio propagation from point-to-point is affected by the physical channel in many ways. A signal arriving at a destination travels through a number of different paths which are referred to as multi-paths. Research in this area of wireless communications has progressed well over the years with the research taking different angles of focus. By this is meant that some researchers focus on ways of reducing or eluding Multipath effects whilst others focus on ways of mitigating the effects of Multipath through compensation schemes. Baseband processing is seen as one field of signal processing that is cardinal to the advancement of software-defined radio technology. This has led to wide research into the carrying out certain algorithms at baseband. This paper considers compensating for Multipath for Frequency Modulated signals. The compensation process is carried out at Radio frequency (RF) and at Quadrature baseband (QBB) and the results are compared. Simulations are carried out using MatLab so as to show the benefits of working at lower QBB frequencies than at RF.

Keywords: quadrature baseband, qadio frequency, qultipath compensation, frequency qodulation, signal processing

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2200 Influence of Recombination of Free and Trapped Charge Carriers on the Efficiency of Conventional and Inverted Organic Solar Cells

Authors: Hooman Mehdizadeh Rad, Jai Singh

Abstract:

Organic solar cells (OSCs) have been actively investigated in the last two decades due to their several merits such as simple fabrication process, low-cost manufacturing, and lightweight. In this paper, using the optical transfer matrix method (OTMM) and solving the drift-diffusion equations processes of recombination are studied in inverted and conventional bulk heterojunction (BHJ) OSCs. Two types of recombination processes are investigated: 1) recombination of free charge carriers using the Langevin theory and 2) of trapped charge carriers in the tail states with exponential energy distribution. These recombination processes are incorporated in simulating the current- voltage characteristics of both conventional and inverted BHJ OSCs. The results of this simulation produces a higher power conversion efficiency in the inverted structure in comparison with conventional structure, which agrees well with the experimental results.

Keywords: conventional organic solar cells, exponential tail state recombination, inverted organic solar cells, Langevin recombination

Procedia PDF Downloads 178
2199 Breast Cancer Sensing and Imaging Utilized Printed Ultra Wide Band Spherical Sensor Array

Authors: Elyas Palantei, Dewiani, Farid Armin, Ardiansyah

Abstract:

High precision of printed microwave sensor utilized for sensing and monitoring the potential breast cancer existed in women breast tissue was optimally computed. The single element of UWB printed sensor that successfully modeled through several numerical optimizations was multiple fabricated and incorporated with woman bra to form the spherical sensors array. One sample of UWB microwave sensor obtained through the numerical computation and optimization was chosen to be fabricated. In overall, the spherical sensors array consists of twelve stair patch structures, and each element was individually measured to characterize its electrical properties, especially the return loss parameter. The comparison of S11 profiles of all UWB sensor elements is discussed. The constructed UWB sensor is well verified using HFSS programming, CST programming, and experimental measurement. Numerically, both HFSS and CST confirmed the potential operation bandwidth of UWB sensor is more or less 4.5 GHz. However, the measured bandwidth provided is about 1.2 GHz due to the technical difficulties existed during the manufacturing step. The configuration of UWB microwave sensing and monitoring system implemented consists of 12 element UWB printed sensors, vector network analyzer (VNA) to perform as the transceiver and signal processing part, the PC Desktop/Laptop acting as the image processing and displaying unit. In practice, all the reflected power collected from whole surface of artificial breast model are grouped into several numbers of pixel color classes positioned on the corresponding row and column (pixel number). The total number of power pixels applied in 2D-imaging process was specified to 100 pixels (or the power distribution pixels dimension 10x10). This was determined by considering the total area of breast phantom of average Asian women breast size and synchronizing with the single UWB sensor physical dimension. The interesting microwave imaging results were plotted and together with some technical problems arisen on developing the breast sensing and monitoring system are examined in the paper.

Keywords: UWB sensor, UWB microwave imaging, spherical array, breast cancer monitoring, 2D-medical imaging

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2198 Design and Manufacture Detection System for Patient's Unwanted Movements during Radiology and CT Scan

Authors: Anita Yaghobi, Homayoun Ebrahimian

Abstract:

One of the important tools that can help orthopedic doctors for diagnose diseases is imaging scan. Imaging techniques can help physicians in see different parts of the body, including the bones, muscles, tendons, nerves, and cartilage. During CT scan, a patient must be in the same position from the start to the end of radiation treatment. Patient movements are usually monitored by the technologists through the closed circuit television (CCTV) during scan. If the patient makes a small movement, it is difficult to be noticed by them. In the present work, a simple patient movement monitoring device is fabricated to monitor the patient movement. It uses an electronic sensing device. It continuously monitors the patient’s position while the CT scan is in process. The device has been retrospectively tested on 51 patients whose movement and distance were measured. The results show that 25 patients moved 1 cm to 2.5 cm from their initial position during the CT scan. Hence, the device can potentially be used to control and monitor patient movement during CT scan and Radiography. In addition, an audible alarm situated at the control panel of the control room is provided with this device to alert the technologists. It is an inexpensive, compact device which can be used in any CT scan machine.

Keywords: CT scan, radiology, X Ray, unwanted movement

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2197 Modeling of Oxygen Supply Profiles in Stirred-Tank Aggregated Stem Cells Cultivation Process

Authors: Vytautas Galvanauskas, Vykantas Grincas, Rimvydas Simutis

Abstract:

This paper investigates a possible practical solution for reasonable oxygen supply during the pluripotent stem cells expansion processes, where the stem cells propagate as aggregates in stirred-suspension bioreactors. Low glucose and low oxygen concentrations are preferred for efficient proliferation of pluripotent stem cells. However, strong oxygen limitation, especially inside of cell aggregates, can lead to cell starvation and death. In this research, the oxygen concentration profile inside of stem cell aggregates in a stem cell expansion process was predicted using a modified oxygen diffusion model. This profile can be realized during the stem cells cultivation process by manipulating the oxygen concentration in inlet gas or inlet gas flow. The proposed approach is relatively simple and may be attractive for installation in a real pluripotent stem cell expansion processes.

Keywords: aggregated stem cells, dissolved oxygen profiles, modeling, stirred-tank, 3D expansion

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2196 Efficacy Study of Post-Tensioned I Girder Made of Ultra-High Performance Fiber Reinforced Concrete and Ordinary Concrete for IRC Loading

Authors: Ayush Satija, Ritu Raj

Abstract:

Escalating demand for elevated structures as a remedy for traffic congestion has led to a surge in the construction of viaducts and bridges predominantly employing prestressed beams. However, post-tensioned I-girder superstructures are gaining traction for their attributes like structural efficiency, cost-effectiveness, and easy construction. Recently, Ultra-high-performance fiber-reinforced concrete (UHPFRC) has emerged as a revolutionary material in reshaping conventional infrastructure engineering. UHPFRC offers exceptional properties including high compressive and tensile strength, alongside enhanced durability. Its adoption in bridges yields benefits, notably a remarkable strength-to-weight ratio enabling the design of lighter and slender structural elements, enhancing functionality and sustainability. Despite its myriad advantages, integration of UHPFRC in construction is still evolving, hindered by factors like cost, material availability, and design standardization. Consequently, there's a need to assess the feasibility of substituting ordinary concrete (OC) with UHPFRC in bridges, focusing on economic considerations. This research undertakes an efficacy study between post-tensioned I-girders fabricated from UHPFRC and OC, evaluating cost parameters associated with concrete production, reinforcement, and erection. The study reveals that UHPFRC becomes economically viable for spans exceeding 40.0m. This shift in cost-effectiveness is attributed to factors like reduced girder depth, elimination of un-tensioned steel, diminished need for shear reinforcement and decreased erection costs.

Keywords: post tensioned I girder, superstructure, ultra-high-performance fiber reinforced concrete, ordinary concrete

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2195 Portable Glove Controlled Video Game for Hand Rehabilitation

Authors: Vinesh Janarthanan, Mohammad H. Rahman

Abstract:

There are numerous neurological conditions that may result in a loss of motor function. Such conditions may include cerebral palsy, Parkinson’s disease, stroke or multiple sclerosis. Due to impaired motor function, specifically in the hand and arm, living independently becomes tremendously more difficult. Rehabilitation programs are the main method to treat these kinds of disabled individuals. However, these programs require longtime commitment from the clinicians/therapists, demand person to person caring, and typically the treatment duration is usually very long. Aside from the treatment received from the therapist, the continuation of neuroplasticity at home is essential to maximizing development and restoring the biological function. To contribute in this area, we have researched and developed a portable and comfortable hand glove for fine motor skills rehabilitation. The glove provides interactive home-based therapy to engage the patient with simple games. The key to this treatment is the repetition of moving the hand and being capable of positioning the hand in various ways.

Keywords: home based, wearable sensors, glove, rehabilitation, motor function, video games

Procedia PDF Downloads 140
2194 Viability of Slab Sliding System for Single Story Structure

Authors: C. Iihoshi, G. A. MacRae, G. W. Rodgers, J. G. Chase

Abstract:

Slab Sliding System (SSS) with Coulomb friction interface between slab and supporting frame is a passive structural vibration control technology. The system can significantly reduce the slab acceleration and accompanied lateral force of the frame. At the same time it is expected to cause the slab displacement magnification by sliding movement. To obtain the general comprehensive seismic response of a single story structure, inelastic response spectra were computed for a large ensemble of ground motions and a practical range of structural periods and friction coefficient values. It was shown that long period structures have no trade-off relation between force reduction and displacement magnification with respect to elastic response, unlike short period structures. For structures with the majority of mass in the slab, the displacement magnification value can be predicted according to simple inelastic displacement relation for in elastically responding SDOF structures because the system behaves elastically to a SDOF structure.

Keywords: earthquake, isolation, slab, sliding

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2193 Modelling and Simulation of Milk Fouling

Authors: Harche Rima, Laoufi Nadia Aicha

Abstract:

This work focuses on the study and modeling of the fouling phenomenon in a vertical pipe. In the first step, milk is one of the fluids obeying the phenomenon of fouling because of the denaturation of these proteins, especially lactoglobulin, which is the active element of milk, and to facilitate its use, we chose to study milk as a fouling fluid. In another step, we consider the test section of our installation as a tubular-type heat exchanger that works against the current and in a closed circuit. A simple mathematical model of Kern & Seaton, based on the kinetics of the fouling resistance, was used to evaluate the influence of the operating parameters (fluid flow velocity and exchange wall temperature) on the fouling resistance. The influence of the variation of the fouling resistance with the operating conditions on the efficiency of the heat exchanger and the importance of the dirty state exchange coefficient as an exchange quality control parameter were discussed and examined. On the other hand, an electronic scanning microscope analysis was performed on the milk deposit in order to obtain its actual image and composition, which allowed us to calculate the thickness of this deposit.

Keywords: fouling, milk, tubular heat exchanger, fouling resistance

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2192 Effects of Oil Pollution on Euryglossa orientalis and Psettodes erumei in the Persian Gulf

Authors: Majid Afkhami, Maryam Ehsanpour, Reza Khoshnood, Zahra Khoshnood, Rastin Afkhami

Abstract:

Marine pollution is a global environmental problem. Different human activities on land, in the water and in the air contribute to the contamination of seawater, sediments and organisms with potentially toxic substances. Contaminants can be natural substances or artificially produced compounds. After discharge into the sea, contaminants can stay in the water in dissolved form or they can be removed from the water column through sedimentation to the bottom sediments. Histopathological alterations can be used as indicators for the effects of various anthropogenic pollutants on organisms and are a reflection of the overall health of the entire population in the ecosystem. These histo pathological biomarkers are closely related to other biomarkers of stress since many pollutants have to undergo metabolic activation in order to be able to provoke cellular change in the affected organism. In order to make evaluation of the effects of oil pollution, some heavy metals bioaccumulation and explore their histopathological effects on hepatocytes of Oriental sole (Euryglossa orientalis) and Deep flounder (Psettodes erumei), fishes caught from two areas of north coast of the Persian Gulf: Bandar Abbass and Bandar Lengeh. Concentrations of Ni and V in liver of both species in two sampling regions were in following order: Bandar abbass Bandar lengeh; also between two species, these quantities were higher in P. erumei than E. orientalis in both sampling regions. Histopathology of the liver shows some cellular alterations including: degeneration, necrosis and tissue disruption, and histopathological effects were severe in P. erumei than E. orientalis. Results showed that Bandar Abbass region was more polluted than Bandar Lengeh, and because Ni and V were oil pollution indicators, and two flat fishes were benthic, they can receive considerable amount of oil pollution through their biological activities like feeding. Also higher amounts of heavy metal concentrations and major histopathological effects in E. orientalis showed strong relationship between benthic habitat of the fish and amounts of received pollutants from water and sediments, because E. orientalis is more related to the bottom than P. erumei.

Keywords: heavy metals, flatfishes, Persian Gulf, oil pollution

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2191 Removal of Heavy Metal, Dye and Salinity from Industrial Wastewaters by Banana Rachis Cellulose Micro Crystal-Clay Composite

Authors: Mohd Maniruzzaman, Md. Monjurul Alam, Md. Hafezur Rahaman, Anika Amir Mohona

Abstract:

The consumption of water by various industries is increasing day by day, and the wastewaters from them are increasing as well. These wastewaters consist of various kinds of color, dissolved solids, toxic heavy metals, residual chlorine, and other non-degradable organic materials. If these wastewaters are exposed directly to the environment, it will be hazardous for the environment and personal health. So, it is very necessary to treat these wastewaters before exposing into the environment. In this research, we have demonstrated the successful processing and utilization of fully bio-based cellulose micro crystal (CMC) composite for the removal of heavy metals, dyes, and salinity from industrial wastewaters. Banana rachis micro-cellulose were prepared by acid hydrolysis (H₂SO₄) of banana (Musa acuminata L.) rachis fiber, and Bijoypur raw clay were treated by organic solvent tri-ethyl amine. Composites were prepared with varying different composition of banana rachis nano-cellulose and modified Bijoypur (north-east part in Bangladesh) clay. After the successful characterization of cellulose micro crystal (CMC) and modified clay, our targeted filter was fabricated with different composition of cellulose micro crystal and clay in the locally fabricated packing column with 7.5 cm as thickness of composites fraction. Waste-water was collected from local small textile industries containing basic yellow 2 as dye, lead (II) nitrate [Pb(NO₃)₂] and chromium (III) nitrate [Cr(NO₃)₃] as heavy metals and saline water was collected from Khulna to test the efficiency of banana rachis cellulose micro crystal-clay composite for removing the above impurities. The filtering efficiency of wastewater purification was characterized by Fourier transforms infrared spectroscopy (FTIR), X-ray diffraction (X-RD), thermo gravimetric analysis (TGA), atomic absorption spectrometry (AAS), scanning electron microscopy (SEM) analyses. Finally, our all characterizations data are shown with very high expected results for in industrial application of our fabricated filter.

Keywords: banana rachis, bio-based filter, cellulose micro crystal-clay composite, wastewaters, synthetic dyes, heavy metal, water salinity

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2190 Modeling of Masonry In-Filled R/C Frame to Evaluate Seismic Performance of Existing Building

Authors: Tarek M. Alguhane, Ayman H. Khalil, M. N. Fayed, Ayman M. Ismail

Abstract:

This paper deals with different modeling aspects of masonry infill: no infill model, Layered shell infill model, and strut infill model. These models consider the complicated behavior of the in-filled plane frames under lateral load similar to an earthquake load. Three strut infill models are used: NBCC (2005) strut infill model, ASCE/SEI 41-06 strut infill model and proposed strut infill model based on modification to Canadian, NBCC (2005) strut infill model. Pushover and modal analyses of a masonry infill concrete frame with a single storey and an existing 5-storey RC building have been carried out by using different models for masonry infill. The corresponding hinge status, the value of base shear at target displacement as well as their dynamic characteristics have been determined and compared. A validation of the structural numerical models for the existing 5-storey RC building has been achieved by comparing the experimentally measured and the analytically estimated natural frequencies and their mode shapes. This study shows that ASCE/SEI 41-06 equation underestimates the values for the equivalent properties of the diagonal strut while Canadian, NBCC (2005) equation gives realistic values for the equivalent properties. The results indicate that both ASCE/SEI 41-06 and Canadian, NBCC (2005) equations for strut infill model give over estimated values for dynamic characteristic of the building. Proposed modification to Canadian, NBCC (2005) equation shows that the fundamental dynamic characteristic values of the building are nearly similar to the corresponding values using layered shell elements as well as measured field results.

Keywords: masonry infill, framed structures, RC buildings, non-structural elements

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2189 The Traveling Behavior and Needs for Tourist Support Facilities of Inbound Tourists Visiting Ratanakosin Island

Authors: Sakul Jariyachamsit

Abstract:

The objectives of this research were to study the behaviour of inbound tourist who visited Ratanakosin Island and to study their needs concerning support facilities. The independent variables included gender, age, levels of education, occupation, and income while the dependent variables were classified into two groups: tourists’ behaviour variables and tourists’ need of supporting facilities. A simple random sampling method was utilized to get 225 respondents. The majority of respondents were both male and female in the same proportion but most were between 21-30 years old. Most were married with a graduated degree. The average income of the respondents was between $20,000-30,000. The findings revealed that the majority of respondents came to Thailand for the first time and spent about 8 days in Thailand and preferred to travel in small groups. Their decision to come to Thailand was influenced by word of mouth. When they first thought of Thailand, they thought of Thai food. In terms of the needs for tourists around the Ratanakosin Island, and ranked in importance, are as follows: a tourist centre, somebody who can speak English, a trustable agency, police patrol, and the availability of maps and brochures.

Keywords: Rattanakosin Island, tourist, travelling behaviour, media engineering

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2188 Semantic Textual Similarity on Contracts: Exploring Multiple Negative Ranking Losses for Sentence Transformers

Authors: Yogendra Sisodia

Abstract:

Researchers are becoming more interested in extracting useful information from legal documents thanks to the development of large-scale language models in natural language processing (NLP), and deep learning has accelerated the creation of powerful text mining models. Legal fields like contracts benefit greatly from semantic text search since it makes it quick and easy to find related clauses. After collecting sentence embeddings, it is relatively simple to locate sentences with a comparable meaning throughout the entire legal corpus. The author of this research investigated two pre-trained language models for this task: MiniLM and Roberta, and further fine-tuned them on Legal Contracts. The author used Multiple Negative Ranking Loss for the creation of sentence transformers. The fine-tuned language models and sentence transformers showed promising results.

Keywords: legal contracts, multiple negative ranking loss, natural language inference, sentence transformers, semantic textual similarity

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2187 Extraction, Synthesis, Characterization and Antioxidant Properties of Oxidized Starch from an Abundant Source in Nigeria

Authors: Okafor E. Ijeoma, Isimi C. Yetunde, Okoh E. Judith, Kunle O. Olobayo, Emeje O. Martins

Abstract:

Starch has gained interest as a renewable and environmentally compatible polymer due to the increase in its use. However, starch by itself could not be satisfactorily applied in industrial processes due to some inherent disadvantages such as its hydrophilic character, poor mechanical properties, its inability to withstand processing conditions such as extreme temperatures, diverse pH, high shear rate, freeze-thaw variation and dimensional stability. The range of physical properties of parent starch can be enlarged by chemical modification which invariably enhances their use in a number of applications found in industrial processes and food manufacture. In this study, Manihot esculentus starch was subjected to modification by oxidation. Fourier Transmittance Infra- Red (FTIR) and Raman spectroscopies were used to confirm the synthesis while Scanning Electron Microscopy (SEM) and X- Ray Diffraction (XRD) were used to characterize the new polymer. DPPH (2, 2-diphenyl-1-picryl-hydrazyl-hydrate) free radical assay was used to determine the antioxidant property of the oxidized starch. Our results show that the modification had no significant effect on the foaming capacity as well as on the emulsion capacity. Scanning electron microscopy revealed that oxidation did not alter the predominantly circular-shaped starch granules, while the X-ray pattern of both starch, native and modified were similar. FTIR results revealed a new band at 3007 and 3283cm-1. Differential scanning calorimetry returned two new endothermic peaks in the oxidized starch with an improved gelation capacity and increased enthalpy of gelatinization. The IC50 of oxidized starch was notably higher than that of the reference standard, ascorbic acid.

Keywords: antioxidant activity, DPPH, M. esculentus, oxidation, starch

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2186 Experimental-Numerical Inverse Approaches in the Characterization and Damage Detection of Soft Viscoelastic Layers from Vibration Test Data

Authors: Alaa Fezai, Anuj Sharma, Wolfgang Mueller-Hirsch, André Zimmermann

Abstract:

Viscoelastic materials have been widely used in the automotive industry over the last few decades with different functionalities. Besides their main application as a simple and efficient surface damping treatment, they may ensure optimal operating conditions for on-board electronics as thermal interface or sealing layers. The dynamic behavior of viscoelastic materials is generally dependent on many environmental factors, the most important being temperature and strain rate or frequency. Prior to the reliability analysis of systems including viscoelastic layers, it is, therefore, crucial to accurately predict the dynamic and lifetime behavior of these materials. This includes the identification of the dynamic material parameters under critical temperature and frequency conditions along with a precise damage localization and identification methodology. The goal of this work is twofold. The first part aims at applying an inverse viscoelastic material-characterization approach for a wide frequency range and under different temperature conditions. For this sake, dynamic measurements are carried on a single lap joint specimen using an electrodynamic shaker and an environmental chamber. The specimen consists of aluminum beams assembled to adapter plates through a viscoelastic adhesive layer. The experimental setup is reproduced in finite element (FE) simulations, and frequency response functions (FRF) are calculated. The parameters of both the generalized Maxwell model and the fractional derivatives model are identified through an optimization algorithm minimizing the difference between the simulated and the measured FRFs. The second goal of the current work is to guarantee an on-line detection of the damage, i.e., delamination in the viscoelastic bonding of the described specimen during frequency monitored end-of-life testing. For this purpose, an inverse technique, which determines the damage location and size based on the modal frequency shift and on the change of the mode shapes, is presented. This includes a preliminary FE model-based study correlating the delamination location and size to the change in the modal parameters and a subsequent experimental validation achieved through dynamic measurements of specimen with different, pre-generated crack scenarios and comparing it to the virgin specimen. The main advantage of the inverse characterization approach presented in the first part resides in the ability of adequately identifying the material damping and stiffness behavior of soft viscoelastic materials over a wide frequency range and under critical temperature conditions. Classic forward characterization techniques such as dynamic mechanical analysis are usually linked to limitations under critical temperature and frequency conditions due to the material behavior of soft viscoelastic materials. Furthermore, the inverse damage detection described in the second part guarantees an accurate prediction of not only the damage size but also its location using a simple test setup and outlines; therefore, the significance of inverse numerical-experimental approaches in predicting the dynamic behavior of soft bonding layers applied in automotive electronics.

Keywords: damage detection, dynamic characterization, inverse approaches, vibration testing, viscoelastic layers

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2185 Ductility Reduction Factors for Displacement Spectra Corresponding to Soft Soil Zone of the Valley of Mexico

Authors: Noé D. Lazos-Gallardo, Sonia E. Ruiz, Federico Valenzuela-Beltran

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A simplified mathematical expression to estimate ductility reduction factors of the displacement spectra corresponding to the soft soil zone of Mexico City is proposed. The aim is to allow a better characterization of the displacement spectra and provide a simple expression to be used in displacement based design (DBD). Emphasis is on the Mexico City Building Code. The study is based on the analysis of single degree of freedom (SDOF) systems with elasto-plastic hysteretic behavior. Several seismic ground motions corresponding to subduction events with magnitudes equal to or greater than 6 and recorded in different stations of Mexico City are used. The proposed expression involves the ratio of elastic and inelastic pseudo-aceleration spectra, and depends on factors such the ductility demand and the vibration period of the structural system. The resulting ductility reduction factors obtained in this study are compared with others existing in the literature, and their advantages and disadvantages are discussed.

Keywords: displacement based design, displacements spectrum, ductility reduction factors, soft soil

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2184 The Interactive Effects of Leadership on Safety

Authors: Jane E. Mullen, Kevin Kelloway, Ann Rhéaume-Brüning

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The purpose of this study is to examine the effects of perceived leader word-action alignment on subordinate extra-role safety behavior. Using survey data gathered from a sample of nurses employed in health care facilities located in Eastern Canada (n = 192), the effects of perceived word-action alignment (measured as the cross product of leaders speaking positively about safety and acting safely) on nurse safety participation was examined. Moderated regression analysis resulted in the significant (p < .01) prediction of nurse safety participation by the interaction term. Analysis of the simple slopes comprising the interaction term suggests that positively speaking about safety only predicted safety participation when leaders were also perceived by subordinates as acting safely. The results provide empirical support for the importance of the perceived alignment between leaders’ words, or espoused safety values and priorities, and their actions. Practical implications for safety leadership training are discussed.

Keywords: leadership, safety participation, safety performance, safety training

Procedia PDF Downloads 364