Search results for: manual areal profiling technique
Commenced in January 2007
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Edition: International
Paper Count: 7374

Search results for: manual areal profiling technique

5574 The Application of Lesson Study Model in Writing Review Text in Junior High School

Authors: Sulastriningsih Djumingin

Abstract:

This study has some objectives. It aims at describing the ability of the second-grade students to write review text without applying the Lesson Study model at SMPN 18 Makassar. Second, it seeks to describe the ability of the second-grade students to write review text by applying the Lesson Study model at SMPN 18 Makassar. Third, it aims at testing the effectiveness of the Lesson Study model in writing review text at SMPN 18 Makassar. This research was true experimental design with posttest Only group design involving two groups consisting of one class of the control group and one class of the experimental group. The research populations were all the second-grade students at SMPN 18 Makassar amounted to 250 students consisting of 8 classes. The sampling technique was purposive sampling technique. The control class was VIII2 consisting of 30 students, while the experimental class was VIII8 consisting of 30 students. The research instruments were in the form of observation and tests. The collected data were analyzed using descriptive statistical techniques and inferential statistical techniques with t-test types processed using SPSS 21 for windows. The results shows that: (1) of 30 students in control class, there are only 14 (47%) students who get the score more than 7.5, categorized as inadequate; (2) in the experimental class, there are 26 (87%) students who obtain the score of 7.5, categorized as adequate; (3) the Lesson Study models is effective to be applied in writing review text. Based on the comparison of the ability of the control class and experimental class, it indicates that the value of t-count is greater than the value of t-table (2.411> 1.667). It means that the alternative hypothesis (H1) proposed by the researcher is accepted.

Keywords: application, lesson study, review text, writing

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5573 Water-Sensitive Landscaping in Desert-Located Egyptian Cities through Sheer Reductions of Turfgrass and Efficient Water Use

Authors: Sarah M. Asar, Nabeel M. Elhady

Abstract:

Egypt’s current per capita water share indicates that the country suffers and has been suffering from water poverty. The abundant utilization of turfgrass in Egypt’s new urban settlements, the reliance on freshwater for irrigation, and the inadequate plant selection increase the water demand in such settlements. Decreasing the surface area of turfgrass by using alternative landscape features such as mulching, using ornamental low-maintenance plants, increasing pathways, etc., could significantly decrease the water demand of urban landscapes. The use of Ammochloa palaestina, Cenchrus crientalis (Oriental Fountain Grass), and Cistus parviflorus (with water demands of approximately 0.005m³/m²/day) as alternatives for Cynodon dactylon (0.01m³/m²/day), which is the most commonly used grass species in Egypt’s landscape, could decrease an area’s water demand by approximately 40-50%. Moreover, creating hydro-zones of similar water demanding plants would enable irrigation facilitation rather than the commonly used uniformed irrigation. Such a practice could further reduce water consumption by 15-20%. These results are based on a case-study analysis of one of Egypt’s relatively new urban settlements, Al-Rehab. Such results emphasize the importance of utilizing native, drought-tolerant vegetation in the urban landscapes of Egypt to reduce irrigation demands. Furthermore, proper implementation, monitoring, and maintenance of automated irrigation systems could be an important factor in a space’s efficient water use. As most new urban settlements in Egypt adopt sprinkler and drip irrigation systems, the lack of maintenance leads to the manual operation of such systems, and, thereby, excessive irrigation occurs.

Keywords: alternative landscape, native plants, efficient irrigation, low water demand

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5572 Flexural Behavior of Eco-Friendly Prefabricated Low Cost Bamboo Reinforced Wall Panels

Authors: Vishal Puri, Pradipta Chakrabortty, Swapan Majumdar

Abstract:

Precast concrete construction is the most commonly used technique for a rapid construction. This technique is very frequently used in the developed countries. Different guidelines required to utilize the potential of prefabricated construction are still not available in the developing countries. This causes over dependence on in-situ construction procedure which further affects the quality, scheduling, and duration of construction. Also with the ever increasing costs of building materials and their negative impact on the environment it has become imperative to look out for alternate construction materials which are cheap and sustainable. Bamboo and fly ash are alternate construction materials having great potential in the construction industry. Thus there is a great need to develop prefabricated components by utilizing the potential of these materials. Bamboo reinforced beams, bamboo reinforced columns and bamboo arches as researched previously have shown great prospects for prefabricated construction industry. But, many other prefabricated components still need to be studied and widely tested before their utilization in the prefabricated construction industry. In the present study, authors have showcased prefabricated bamboo reinforced wall panel for the prefabricated construction industry. It presents a detailed methodology for the development of such prefabricated panels. It also presents the flexural behavior of such panels as tested under flexural loads following ASTM guidelines. It was observed that these wall panels are much flexible and do not show brittle failure as observed in traditional brick walls. It was observed that prefabricated walls are about 42% cheaper as compared to conventional brick walls. It was also observed that prefabricated walls are considerably lighter in weight and are environment friendly. It was thus concluded that this type of wall panels are an excellent alternative for partition brick walls.

Keywords: bamboo, prefabricated walls, reinforced structure, sustainable infrastructure

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5571 Antibacterial Wound Dressing Based on Metal Nanoparticles Containing Cellulose Nanofibers

Authors: Mohamed Gouda

Abstract:

Antibacterial wound dressings based on cellulose nanofibers containing different metal nanoparticles (CMC-MNPs) were synthesized using an electrospinning technique. First, the composite of carboxymethyl cellulose containing different metal nanoparticles (CMC/MNPs), such as copper nanoparticles (CuNPs), iron nanoparticles (FeNPs), zinc nanoparticles (ZnNPs), cadmium nanoparticles (CdNPs) and cobalt nanoparticles (CoNPs) were synthesized, and finally, these composites were transferred to the electrospinning process. Synthesized CMC-MNPs were characterized using scanning electron microscopy (SEM) coupled with high-energy dispersive X-ray (EDX) and UV-visible spectroscopy used to confirm nanoparticle formation. The SEM images clearly showed regular flat shapes with semi-porous surfaces. All MNPs were well distributed inside the backbone of the cellulose without aggregation. The average particle diameters were 29-39 nm for ZnNPs, 29-33 nm for CdNPs, 25-33 nm for CoNPs, 23-27 nm for CuNPs and 22-26 nm for FeNPs. Surface morphology, water uptake and release of MNPs from the nanofibers in water and antimicrobial efficacy were studied. SEM images revealed that electrospun CMC-MNPs nanofibers are smooth and uniformly distributed without bead formation with average fiber diameters in the range of 300 to 450 nm. Fiber diameters were not affected by the presence of MNPs. TEM images showed that MNPs are present in/on the electrospun CMC-MNPs nanofibers. The diameter of the electrospun nanofibers containing MNPs was in the range of 300–450 nm. The MNPs were observed to be spherical in shape. The CMC-MNPs nanofibers showed good hydrophilic properties and had excellent antibacterial activity against the Gram-negative bacteria Escherichia coli and the Gram-positive bacteria Staphylococcus aureus.

Keywords: electrospinning technique, metal nanoparticles, cellulosic nanofibers, wound dressing

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5570 A Vehicle Monitoring System Based on the LoRa Technique

Authors: Chao-Linag Hsieh, Zheng-Wei Ye, Chen-Kang Huang, Yeun-Chung Lee, Chih-Hong Sun, Tzai-Hung Wen, Jehn-Yih Juang, Joe-Air Jiang

Abstract:

Air pollution and climate warming become more and more intensified in many areas, especially in urban areas. Environmental parameters are critical information to air pollution and weather monitoring. Thus, it is necessary to develop a suitable air pollution and weather monitoring system for urban areas. In this study, a vehicle monitoring system (VMS) based on the IoT technique is developed. Cars are selected as the research tool because it can reach a greater number of streets to collect data. The VMS can monitor different environmental parameters, including ambient temperature and humidity, and air quality parameters, including PM2.5, NO2, CO, and O3. The VMS can provide other information, including GPS signals and the vibration information through driving a car on the street. Different sensor modules are used to measure the parameters and collect the measured data and transmit them to a cloud server through the LoRa protocol. A user interface is used to show the sensing data storing at the cloud server. To examine the performance of the system, a researcher drove a Nissan x-trail 1998 to the area close to the Da’an District office in Taipei to collect monitoring data. The collected data are instantly shown on the user interface. The four kinds of information are provided by the interface: GPS positions, weather parameters, vehicle information, and air quality information. With the VMS, users can obtain the information regarding air quality and weather conditions when they drive their car to an urban area. Also, government agencies can make decisions on traffic planning based on the information provided by the proposed VMS.

Keywords: LoRa, monitoring system, smart city, vehicle

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5569 Three-Dimensional Vibration Characteristics of Piezoelectric Semi-Spherical Shell

Authors: Yu-Hsi Huang, Ying-Der Tsai

Abstract:

Piezoelectric circular plates can provide out-of-plane vibrational displacements on low frequency and in-plane vibrational displacements on high frequency. Piezoelectric semi-spherical shell, which is double-curvature structure, can induce three-dimensional vibrational displacements over a large frequency range. In this study, three-dimensional vibrational characteristics of piezoelectric semi-spherical shells with free boundary conditions are investigated using three experimental methods and finite element numerical modeling. For the experimental measurements, amplitude-fluctuation electronic speckle pattern interferometry (AF-ESPI) is used to obtain resonant frequencies and radial and azimuthal mode shapes. This optical technique utilizes a full-field and non-contact optical system that measures both the natural frequency and corresponding vibration mode shape simultaneously in real time. The second experimental technique used, laser displacement meter is a point-wise displacement measurement method that determines the resonant frequencies of the piezoelectric shell. An impedance analyzer is used to determine the in-plane resonant frequencies of the piezoelectric semi-spherical shell. The experimental results of the resonant frequencies and mode shapes for the piezoelectric shell are verified with the result from finite element analysis. Excellent agreement between the experimental measurements and numerical calculation is presented on the three-dimensional vibrational characteristics of the piezoelectric semi-spherical shell.

Keywords: piezoelectric semi-spherical shell, mode shape, resonant frequency, electronic speckle pattern interferometry, radial vibration, azimuthal vibration

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5568 Homogenization of a Non-Linear Problem with a Thermal Barrier

Authors: Hassan Samadi, Mustapha El Jarroudi

Abstract:

In this work, we consider the homogenization of a non-linear problem in periodic medium with two periodic connected media exchanging a heat flux throughout their common interface. The interfacial exchange coefficient λ is assumed to tend to zero or to infinity following a rate λ=λ(ε) when the size ε of the basic cell tends to zero. Three homogenized problems are determined according to some critical value depending of λ and ε. Our method is based on Γ-Convergence techniques.

Keywords: variational methods, epiconvergence, homogenization, convergence technique

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5567 Microbiological Assessment of Soft Cheese (Wara), Raw Milk and Dairy Drinking Water from Selected Farms in Ido, Ibadan, Nigeria

Authors: Blessing C. Nwachukwu, Michael O. Taiwo, Wasiu A. Abibu, Isaac O. Ayodeji

Abstract:

Milk is an important source of micro and macronutrients for humans. Soft Cheese (Wara) is an example of a by-product of milk. In addition, water is considered as one of the most vital resources in cattle farms. Due to the high consumption rate of milk and soft cheese and the traditional techniques involved in their production in Nigeria, there was a need for a microbiological assessment which will be of utmost public health importance. The study thus investigated microbial risk assessments associated with consumption of milk and soft cheese (Wara). It also investigated common pathogens present in dairy water in farms and antibiotic sensitivity profiling for implicated pathogens were conducted. Samples were collected from three different Fulani dairy herds in Ido local government, Ibadan, Oyo State, Nigeria and subjected to microbiological evaluation and antimicrobial susceptibility testing. Aspergillus flavus was the only isolated fungal isolate from Wara while Staphylococcus aureus, Vibro cholera, Hafnia alvei, Proteus mirabilis, Escherishia coli, Psuedomonas aeuroginosa, Citrobacter freundii, and Klebsiella pneumonia were the bacteria genera isolated from Wara, dairy milk and dairy drinking water. Bacterial counts from Wara from the three selected farms A, B and C were 3.5×105 CFU/ml, 4.0×105 CFU/ml and 5.3×105 CFU/ml respectively while the fungal count was 3CFU/100µl. The total bacteria count from dairy milk from the three selected farms A, B and C were Farms 2.0 ×105 CFU/ml, 3.5 × 105 CFU/ml and 6.5 × 105 CFU/ml respectively. 1.4×105 CFU/ml, 1.9×105 CFU/ml and 4.9×105 CFU/ml were the recorded bacterial counts from dairy water from farms A, B and C respectively. The highest antimicrobial resistance of 100% was recorded in Wara with Enrofloxacin, Gentamycin, Cefatriaxone and Colistin. The highest antimicrobial susceptibility of 100% was recorded in Raw milk with Enrofloxacin and Gentamicin. Highest antimicrobial intermediate response of 100% was recorded in Raw milk with Streptomycin. The study revealed that most of the cheeses sold at Ido local Government are contaminated with pathogens. Further research is needed on standardizing the production method to prevent pathogens from gaining access. The presence of bacteria in raw milk indicated contamination due to poor handling and unhygienic practices. Thus, drinking unpasteurized milk is hazardous as it increases the risk of zoonoses. Also, the Provision of quality drinking water is crucial for optimum productivity of dairy. Health education programs aiming at increasing awareness of the importance of clean water for animal health will be helpful.

Keywords: dairy, raw milk, soft cheese, Wara

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5566 An Effective Approach to Knowledge Capture in Whole Life Costing in Constructions Project

Authors: Ndibarafinia Young Tobin, Simon Burnett

Abstract:

In spite of the benefits of implementing whole life costing technique as a valuable approach for comparing alternative building designs allowing operational cost benefits to be evaluated against any initial cost increases and also as part of procurement in the construction industry, its adoption has been relatively slow due to the lack of tangible evidence, ‘know-how’ skills and knowledge of the practice, i.e. the lack of professionals in many establishments with knowledge and training on the use of whole life costing technique, this situation is compounded by the absence of available data on whole life costing from relevant projects, lack of data collection mechanisms and so on. This has proved to be very challenging to those who showed some willingness to employ the technique in a construction project. The knowledge generated from a project can be considered as best practices learned on how to carry out tasks in a more efficient way, or some negative lessons learned which have led to losses and slowed down the progress of the project and performance. Knowledge management in whole life costing practice can enhance whole life costing analysis execution in a construction project, as lessons learned from one project can be carried on to future projects, resulting in continuous improvement, providing knowledge that can be used in the operation and maintenance phases of an assets life span. Purpose: The purpose of this paper is to report an effective approach which can be utilised in capturing knowledge in whole life costing practice in a construction project. Design/methodology/approach: An extensive literature review was first conducted on the concept of knowledge management and whole life costing. This was followed by a semi-structured interview to explore the existing and good practice knowledge management in whole life costing practice in a construction project. The data gathered from the semi-structured interview was analyzed using content analysis and used to structure an effective knowledge capturing approach. Findings: From the results obtained in the study, it shows that the practice of project review is the common method used in the capturing of knowledge and should be undertaken in an organized and accurate manner, and results should be presented in the form of instructions or in a checklist format, forming short and precise insights. The approach developed advised that irrespective of how effective the approach to knowledge capture, the absence of an environment for sharing knowledge, would render the approach ineffective. Open culture and resources are critical for providing a knowledge sharing setting, and leadership has to sustain whole life costing knowledge capture, giving full support for its implementation. The knowledge capturing approach has been evaluated by practitioners who are experts in the area of whole life costing practice. The results have indicated that the approach to knowledge capture is suitable and efficient.

Keywords: whole life costing, knowledge capture, project review, construction industry, knowledge management

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5565 Layout Optimization of a Start-up COVID-19 Testing Kit Manufacturing Facility

Authors: Poojan Vora, Hardik Pancholi, Sanket Tajane, Harsh Shah, Elias Keedy

Abstract:

The global COVID-19 pandemic has affected the industry drastically in many ways. Even though the vaccine is being distributed quickly and despite the decreasing number of positive cases, testing is projected to remain a key aspect of the ‘new normal’. Improving existing plant layout and improving safety within the facility are of great importance in today’s industries because of the need to ensure productivity optimization and reduce safety risks. In practice, it is essential for any manufacturing plant to reduce nonvalue adding steps such as the movement of materials and rearrange similar processes. In the current pandemic situation, optimized layouts will not only increase safety measures but also decrease the fixed cost per unit manufactured. In our case study, we carefully studied the existing layout and the manufacturing steps of a new Texas start-up company that manufactures COVID testing kits. The effects of production rate are incorporated with the computerized relative allocation of facilities technique (CRAFT) algorithm to improve the plant layout and estimate the optimization parameters. Our work reduces the company’s material handling time and increases their daily production. Real data from the company are used in the case study to highlight the importance of colleges in fostering small business needs and improving the collaboration between college researchers and industries by using existing models to advance best practices.

Keywords: computerized relative allocation of facilities technique, facilities planning, optimization, start-up business

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5564 A Comparative Study of the Effects of Vibratory Stress Relief and Thermal Aging on the Residual Stress of Explosives Materials

Authors: Xuemei Yang, Xin Sun, Cheng Fu, Qiong Lan, Chao Han

Abstract:

Residual stresses, which can be produced during the manufacturing process of plastic bonded explosive (PBX), play an important role in weapon system security and reliability. Residual stresses can and do change in service. This paper mainly studies the influence of vibratory stress relief (VSR) and thermal aging on residual stress of explosives. Firstly, the residual stress relaxation of PBX via different physical condition of VSR, such as vibration time, amplitude and dynamic strain, were studied by drill-hole technique. The result indicated that the vibratory amplitude, time and dynamic strain had a significant influence on the residual stress relief of PBX. The rate of residual stress relief of PBX increases first and then decreases with the increase of dynamic strain, amplitude and time, because the activation energy is too small to make the PBX yield plastic deformation at first. Then the dynamic strain, time and amplitude exceed a certain threshold, the residual stress changes show the same rule and decrease sharply, this sharply drop of residual stress relief rate may have been caused by over vibration. Meanwhile, the comparison between VSR and thermal aging was also studied. The conclusion is that the reduction ratio of residual stress after VSR process with applicable vibratory parameters could be equivalent to 73% of thermal aging with 7 days. In addition, the density attenuation rate, mechanical property, and dimensional stability with 3 months after VSR process was almost the same compared with thermal aging. However, compared with traditional thermal aging, VSR only takes a very short time, which greatly improves the efficiency of aging treatment for explosive materials. Therefore, the VSR could be a potential alternative technique in the industry of residual stress relaxation of PBX explosives.

Keywords: explosives, residual stresses, thermal aging, vibratory stress relief, VSR

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5563 Laser Corneoplastique™: A Refractive Surgery for Corneal Scars

Authors: Arun C. Gulani, Aaishwariya A. Gulani, Amanda Southall

Abstract:

Background: Laser Corneoplastique™ as a least interventional, visually promising technique for patients with vision disability from corneal scars of varied causes has been retrospectively reviewed and proves to cause a paradigm shift in mindset and approach towards corneal scars as a Refractive surgery aiming for emmetropic, unaided vision of 20;/20 in most cases. Three decades of work on this technique has been compiled in this 15-year study. Subject and Methods: The objective of this study was to determine the success of Laser Corneoplastique™ surgery as a treatment of corneal scar cases. A survey of corneal scar cases caused by various medical histories that had undergone Laser Corneoplastique™ surgery over the past twenty years by a single surgeon Arun C. Gulani, M.D. were retrospectively reviewed. The details of each of the cases were retrieved from their medical records and analyzed. Each patient had been examined thoroughly at their preoperative appointments for stability of refraction and vision, depth of scar, pachymetry, topography, pattern of the scar and uncorrected and best corrected vision potential, which were all taken into account in the patients' treatment plans. Results: 64 eyes of 53 patients were investigated for scar etiology, keratometry, visual acuity, and complications. There were 25 different etiologies seen, with the most common being a Herpetic scar. The average visual acuity post-op was, on average, 20/23.55 (±7.05). Laser parameters used were depth and pulses. Overall, the mean Laser ablation depth was 30.67 (±19.05), ranging from 2 to 73 µm. Number of Laser pulses averaged 191.85 (±112.02). Conclusion: Refractive Laser Corneoplastique™ surgery, when practiced as an art, can address all levels of ametropia while reversing complex corneas and scars from refractive surgery complications back to 20/20 vision.

Keywords: corneal scar, refractive surgery, corneal transplant, laser corneoplastique

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5562 A Relative Entropy Regularization Approach for Fuzzy C-Means Clustering Problem

Authors: Ouafa Amira, Jiangshe Zhang

Abstract:

Clustering is an unsupervised machine learning technique; its aim is to extract the data structures, in which similar data objects are grouped in the same cluster, whereas dissimilar objects are grouped in different clusters. Clustering methods are widely utilized in different fields, such as: image processing, computer vision , and pattern recognition, etc. Fuzzy c-means clustering (fcm) is one of the most well known fuzzy clustering methods. It is based on solving an optimization problem, in which a minimization of a given cost function has been studied. This minimization aims to decrease the dissimilarity inside clusters, where the dissimilarity here is measured by the distances between data objects and cluster centers. The degree of belonging of a data point in a cluster is measured by a membership function which is included in the interval [0, 1]. In fcm clustering, the membership degree is constrained with the condition that the sum of a data object’s memberships in all clusters must be equal to one. This constraint can cause several problems, specially when our data objects are included in a noisy space. Regularization approach took a part in fuzzy c-means clustering technique. This process introduces an additional information in order to solve an ill-posed optimization problem. In this study, we focus on regularization by relative entropy approach, where in our optimization problem we aim to minimize the dissimilarity inside clusters. Finding an appropriate membership degree to each data object is our objective, because an appropriate membership degree leads to an accurate clustering result. Our clustering results in synthetic data sets, gaussian based data sets, and real world data sets show that our proposed model achieves a good accuracy.

Keywords: clustering, fuzzy c-means, regularization, relative entropy

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5561 Pattern the Location and Area of Earth-Dumping Stations from Vehicle GPS Data in Taiwan

Authors: Chun-Yuan Chen, Ming-Chang Li, Xiu-Hui Wen, Yi-Ching Tu

Abstract:

The objective of this study explores GPS (Global Positioning System) applied to trace construction vehicles such as trucks or cranes, help to pattern the earth-dumping stations of traffic construction in Taiwan. Traffic construction in this research is defined as the engineering of high-speed railways, expressways, and which that distance more than kilometers. Audit the location and check the compliance with regulations of earth-dumping stations is one of important tasks in Taiwan EPA. Basically, the earth-dumping station was known as one source of particulate matter from air pollution during construction process. Due to GPS data can be analyzed quickly and be used conveniently, this study tried to find out dumping stations by modeling vehicles tracks from GPS data during work cycle of construction. The GPS data updated from 13 vehicles related to an expressway construction in central Taiwan. The GPS footprints were retrieved to Keyhole Markup Language (KML) files so that can pattern the tracks of trucks by computer applications, the data was collected about eight months- from Feb. to Oct. in 2017. The results of GPS footprints identified dumping station and outlined the areas of earthwork had been passed to the Taiwan EPA for on-site inspection. Taiwan EPA had issued advice comments to the agency which was in charge of the construction to prevent the air pollution. According to the result of this study compared to the commonly methods in inspecting environment by manual collection, the GPS with KML patterning and modeling method can consumes less time. On the other hand, through monitoring the GPS data from construction vehicles could be useful for administration to development and implementation of strategies in environmental management.

Keywords: automatic management, earth-dumping station, environmental management, Global Positioning System (GPS), particulate matter, traffic construction

Procedia PDF Downloads 154
5560 In-Service Training to Enhance Community Based Corrections

Authors: Varathagowry Vasudevan

Abstract:

This paper attempts to demonstrate the importance of capacity building of the para-professionals in community based corrections for enhancing family and child welfare as a crucial factor in providing in-service training as a responsive methodology in community based corrections to enhance the best practices. The Diploma programme in community-based corrections initiated by the National Institute of Social Development has been engaged in this noble task of training quality personnel knowledgeable in the best practices and fieldwork skills on community-based correction and its best practice. To protect the families and children and enhance best practices, National Institute of Social Development with support from the department of community-based corrections initiated a Diploma programme in community-based corrections to enhance and update the knowledge, skills, attitudes with the right mindset of the work supervisors employed at the department of community-based corrections. This study based on reflective practice illustrated the effectiveness of curriculum of in-service training programme as a tool to enhance the capacities of the relevant officers in Sri Lanka. The data for the study was obtained from participants and coordinator through classroom discussions and key informant interviews. This study showed that use of appropriate tailor-made curriculum and field practice manual by the officers during the training was very much dependent on the provision of appropriate administrative facilities, passion, teaching methodology that promote capacity to involve best practices. It also demonstrated further the fact that professional social work response, strengthening families within legal framework was very much grounded in the adoption of proper skills imbibed through training in appropriate methodology practiced in the field under guided supervision.

Keywords: capacity building, community-based corrections, in-service training, paraprofessionals

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5559 Digitalization and High Audit Fees: An Empirical Study Applied to US Firms

Authors: Arpine Maghakyan

Abstract:

The purpose of this paper is to study the relationship between the level of industry digitalization and audit fees, especially, the relationship between Big 4 auditor fees and industry digitalization level. On the one hand, automation of business processes decreases internal control weakness and manual mistakes; increases work effectiveness and integrations. On the other hand, it may cause serious misstatements, high business risks or even bankruptcy, typically in early stages of automation. Incomplete automation can bring high audit risk especially if the auditor does not fully understand client’s business automation model. Higher audit risk consequently will cause higher audit fees. Higher audit fees for clients with high automation level are more highlighted in Big 4 auditor’s behavior. Using data of US firms from 2005-2015, we found that industry level digitalization is an interaction for the auditor quality on audit fees. Moreover, the choice of Big4 or non-Big4 is correlated with client’s industry digitalization level. Big4 client, which has higher digitalization level, pays more than one with low digitalization level. In addition, a high-digitalized firm that has Big 4 auditor pays higher audit fee than non-Big 4 client. We use audit fees and firm-specific variables from Audit Analytics and Compustat databases. We analyze collected data by using fixed effects regression methods and Wald tests for sensitivity check. We use fixed effects regression models for firms for determination of the connections between technology use in business and audit fees. We control for firm size, complexity, inherent risk, profitability and auditor quality. We chose fixed effects model as it makes possible to control for variables that have not or cannot be measured.

Keywords: audit fees, auditor quality, digitalization, Big4

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5558 Performance Evaluation of the CareSTART S1 Analyzer for Quantitative Point-Of-Care Measurement of Glucose-6-Phosphate Dehydrogenase Activity

Authors: Haiyoung Jung, Mi Joung Leem, Sun Hwa Lee

Abstract:

Background & Objective: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a genetic abnormality that results in an inadequate amount of G6PD, leading to increased susceptibility of red blood cells to reactive oxygen species and hemolysis. The present study aimed to evaluate the careSTARTTM S1 analyzer for measuring G6PD activity to hemoglobin (Hb) ratio. Methods: Precision for G6PD activity and hemoglobin measurement was evaluated using control materials with two levels on five repeated runs per day for five days. The analytic performance of the careSTARTTM S1 analyzer was compared with spectrophotometry in 40 patient samples. Reference ranges suggested by the manufacturer were validated in 20 healthy males and females each. Results: The careSTARTTM S1 analyzer demonstrated precision of 6.0% for low-level (14~45 U/dL) and 2.7% for high-level (60~90 U/dL) control in G6PD activity, and 1.4% in hemoglobin (7.9~16.3 u/g Hb). A comparison study of G6PD to Hb ratio between the careSTARTTM S1 analyzer and spectrophotometry showed an average difference of 29.1% with a positive bias of the careSTARTTM S1 analyzer. All normal samples from the healthy population were validated for the suggested reference range for males (≥2.19 U/g Hb) and females (≥5.83 U/g Hb). Conclusion: The careSTARTTM S1 analyzer demonstrated good analytical performance and can replace the current spectrophotometric measurement of G6PD enzyme activity. In the aspect of the management of clinical laboratories, it can be a reasonable option as a point-of-care analyzer with minimal handling of samples and reagents, in addition to the automatic calculation of the ratio of measured G6PD activity and Hb concentration, to minimize any clerical errors involved with manual calculation.

Keywords: POCT, G6PD, performance evaluation, careSTART

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5557 Seismic Assessment of Passive Control Steel Structure with Modified Parameter of Oil Damper

Authors: Ahmad Naqi

Abstract:

Today, the passively controlled buildings are extensively becoming popular due to its excellent lateral load resistance circumstance. Typically, these buildings are enhanced with a damping device that has high market demand. Some manufacturer falsified the damping device parameter during the production to achieve the market demand. Therefore, this paper evaluates the seismic performance of buildings equipped with damping devices, which their parameter modified to simulate the falsified devices, intentionally. For this purpose, three benchmark buildings of 4-, 10-, and 20-story were selected from JSSI (Japan Society of Seismic Isolation) manual. The buildings are special moment resisting steel frame with oil damper in the longitudinal direction only. For each benchmark buildings, two types of structural elements are designed to resist the lateral load with and without damping devices (hereafter, known as Trimmed & Conventional Building). The target building was modeled using STERA-3D, a finite element based software coded for study purpose. Practicing the software one can develop either three-dimensional Model (3DM) or Lumped Mass model (LMM). Firstly, the seismic performance of 3DM and LMM models was evaluated and found excellent coincide for the target buildings. The simplified model of LMM used in this study to produce 66 cases for both of the buildings. Then, the device parameters were modified by ± 40% and ±20% to predict many possible conditions of falsification. It is verified that the building which is design to sustain the lateral load with support of damping device (Trimmed Building) are much more under threat as a result of device falsification than those building strengthen by damping device (Conventional Building).

Keywords: passive control system, oil damper, seismic assessment, lumped mass model

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5556 X-Ray Diffraction, Microstructure, and Mössbauer Studies of Nanostructured Materials Obtained by High-Energy Ball Milling

Authors: N. Boudinar, A. Djekoun, A. Otmani, B. Bouzabata, J. M. Greneche

Abstract:

High-energy ball milling is a solid-state powder processing technique that allows synthesizing a variety of equilibrium and non-equilibrium alloy phases starting from elemental powders. The advantage of this process technology is that the powder can be produced in large quantities and the processing parameters can be easily controlled, thus it is a suitable method for commercial applications. It can also be used to produce amorphous and nanocrystalline materials in commercially relevant amounts and is also amenable to the production of a variety of alloy compositions. Mechanical alloying (high-energy ball milling) provides an inter-dispersion of elements through a repeated cold welding and fracture of free powder particles; the grain size decreases to nano metric scale and the element mix together. Progressively, the concentration gradients disappear and eventually the elements are mixed at the atomic scale. The end products depend on many parameters such as the milling conditions and the thermodynamic properties of the milled system. Here, the mechanical alloying technique has been used to prepare nano crystalline Fe_50 and Fe_64 wt.% Ni alloys from powder mixtures. Scanning electron microscopy (SEM) with energy-dispersive, X-ray analyses and Mössbauer spectroscopy were used to study the mixing at nanometric scale. The Mössbauer Spectroscopy confirmed the ferromagnetic ordering and was use to calculate the distribution of hyperfin field. The Mössbauer spectrum for both alloys shows the existence of a ferromagnetic phase attributed to γ-Fe-Ni solid solution.

Keywords: nanocrystalline, mechanical alloying, X-ray diffraction, Mössbauer spectroscopy, phase transformations

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5555 A Cadaveric Study of Branching Pattern of Arch of Aorta and Its Clinical Significance in Nepalese Population

Authors: Gulam Anwer Khan, A. Gautam

Abstract:

Background: The arch of aorta is a large artery that arches over the root of the left lung and connects the ascending aorta and descending aorta. It is situated in the superior mediastinum behind the manubrium sterni. It gives off three major branches i.e. brachiocephalic trunk, left common carotid artery and left subclavian artery arising from the superior surface of arch of aorta from right to left. Material and Methods: This was a descriptive study. It was carried out in 44 cadavers, obtained during dissections for undergraduates of Department of Anatomy, Chitwan Medical College, Bharatpur, Chitwan, between March 2015 to October 2016. Cadavers of both sexes were included in the present study. The arch of aorta was dissected and exposed according to the methods described by Romanes in Cunningham’s manual of practical anatomy. Results: Out of 44 dissected cadavers, 35 (79.54%) were male and 9 (20.46%) were female cadavers. The normal branching pattern of the arch of aorta was encountered in 28 (63.64%) cadavers and the remaining 16 (36.36%) cadavers showed variations in the branching pattern of arch of aorta. Two different types of variations on the branching pattern of arch of aorta were noted in the present study, in which 12 (27.27%) cadavers had common trunk of the Arch of Aorta. In 3 (5.00%) male cadavers, we found the origin of the Thyroid ima artery. This variation was noted in 1(1.66%) female cadaver. Conclusion: The present study carried out on adult human cadavers’ revealed wide variations in the branching pattern of the arch of ao rta. These variations are of clinical significance and also very useful for the anatomists, radiologists, anesthesiologists, surgeons for practice during angiography, instrumentation, supra-aortic thoracic, head and neck surgery.

Keywords: arch of aorta, brachiocephalic trunk, left common carotid artery, left subclavian artery, Thyroidea ima artery

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5554 Multi-Stage Classification for Lung Lesion Detection on CT Scan Images Applying Medical Image Processing Technique

Authors: Behnaz Sohani, Sahand Shahalinezhad, Amir Rahmani, Aliyu Aliyu

Abstract:

Recently, medical imaging and specifically medical image processing is becoming one of the most dynamically developing areas of medical science. It has led to the emergence of new approaches in terms of the prevention, diagnosis, and treatment of various diseases. In the process of diagnosis of lung cancer, medical professionals rely on computed tomography (CT) scans, in which failure to correctly identify masses can lead to incorrect diagnosis or sampling of lung tissue. Identification and demarcation of masses in terms of detecting cancer within lung tissue are critical challenges in diagnosis. In this work, a segmentation system in image processing techniques has been applied for detection purposes. Particularly, the use and validation of a novel lung cancer detection algorithm have been presented through simulation. This has been performed employing CT images based on multilevel thresholding. The proposed technique consists of segmentation, feature extraction, and feature selection and classification. More in detail, the features with useful information are selected after featuring extraction. Eventually, the output image of lung cancer is obtained with 96.3% accuracy and 87.25%. The purpose of feature extraction applying the proposed approach is to transform the raw data into a more usable form for subsequent statistical processing. Future steps will involve employing the current feature extraction method to achieve more accurate resulting images, including further details available to machine vision systems to recognise objects in lung CT scan images.

Keywords: lung cancer detection, image segmentation, lung computed tomography (CT) images, medical image processing

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5553 Investigating the Prevalence of HCV from Laboratory Centers in Tehran City - Iran by Electrochemiluminescence (ECL) and PCR Techniques

Authors: Zahra Rakhshan Masoudi, Sona Rostampour Yasouri

Abstract:

Considering that the only way to save the lives of patients and healthy people who have suffered sudden accidents is blood transfusion, what is important is the presence of the known HCV virus as the most important cause of the disease after blood transfusion. HCV is one of the major global problems, and its transmission through blood causes life-threatening complications and extensive legal, social and economic consequences. On the one hand, unfortunately, there is still no effective vaccine available to prevent HCV. In Iran, the exact statistics of the prevalence of this disease have not yet been fully announced. The main purpose of this study is to investigate the prevalence rate and rapid diagnosis of HCV among those who refer to laboratory centers in Tehran. From spring to winter of 1401 (2022-2023), 2166 blood samples were collected from laboratory centers in Tehran. Blood samples were evaluated for the presence of HCV by Electrochemiluminescence (ECL) and PCR techniques along with specific HCV primers. In general, 36 samples (1.6%) were tested positive by the mentioned techniques. The results indicated that the ECL technique is a sensitive and specific diagnostic method for detecting HCV in the early stages of the disease and can be very helpful and provide the possibility of starting the treatment steps to prevent the exacerbation of the disease earlier. Also, the results of PCR technique showed that PCR is an accurate, sensitive and fast method for definitive diagnosis of HCV. It seems that the incidence rate of this disease is increasing in Iran, and investigating the spread of the disease throughout Iran for a longer period of time in the continuation of our research can be helpful in the future to take the necessary measures to prevent the transmission of the disease to people and the rapid onset Treatment steps for patients with HCV should be carried out.

Keywords: electrochemiluminescence, HCV, PCR, prevalence

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5552 Precoding-Assisted Frequency Division Multiple Access Transmission Scheme: A Cyclic Prefixes- Available Modulation-Based Filter Bank Multi-Carrier Technique

Authors: Ying Wang, Jianhong Xiang, Yu Zhong

Abstract:

The offset Quadrature Amplitude Modulation-based Filter Bank Multi-Carrier (FBMC) system provides superior spectral properties over Orthogonal Frequency Division Multiplexing. However, seriously affected by imaginary interference, its performances are hampered in many areas. In this paper, we propose a Precoding-Assisted Frequency Division Multiple Access (PA-FDMA) modulation scheme. By spreading FBMC symbols into the frequency domain and transmitting them with a precoding matrix, the impact of imaginary interference can be eliminated. Specifically, we first generate the coding pre-solution matrix with a nonuniform Fast Fourier Transform and pick the best columns by introducing auxiliary factors. Secondly, according to the column indexes, we obtain the precoding matrix for one symbol and impose scaling factors to ensure that the power is approximately constant throughout the transmission time. Finally, we map the precoding matrix of one symbol to multiple symbols and transmit multiple data frames, thus achieving frequency-division multiple access. Additionally, observing the interference between adjacent frames, we mitigate them by adding frequency Cyclic Prefixes (CP) and evaluating them with a signal-to-interference ratio. Note that PA-FDMA can be considered a CP-available FBMC technique because the underlying strategy is FBMC. Simulation results show that the proposed scheme has better performance compared to Single Carrier Frequency Division Multiple Access (SC-FDMA), etc.

Keywords: PA-FDMA, SC-FDMA, FBMC, non-uniform fast fourier transform

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5551 Shooting Gas Cylinders to Prevent Their Explosion in Fire

Authors: Jerzy Ejsmont, Beata Świeczko-Żurek, Grzegorz Ronowski

Abstract:

Gas cylinders in general and particularly cylinders containing acetylene constitute a great potential danger for fire and rescue services involved in salvage operations. Experiments show that gas cylinders with acetylene, oxygen, hydrogen, CNG, LPG or CO2 may blow after short exposition to heat with very destructive effect as fragments of blown cylinder may fly even several hundred meters. In the case of acetylene, the explosion may occur also several hours after the cylinder is cooled down. One of the possible neutralization procedures that in many cases may be used to prevent explosions is shooting dangerous cylinders by rifle bullets. This technique is used to neutralize acetylene cylinders in a few European countries with great success. In Poland research project 'BLOW' was launched in 2014 with the aim to investigate phenomena related to fire influence on industrial and home used cylinders and to evaluate usefulness of the shooting technique. All together over 100 gas cylinders with different gases were experimentally tested at the military blasting grounds and in shelters. During the experiments cylinder temperature and pressure were recorded. In the case of acetylene that is subjected to thermal decomposition also concentration of hydrogen was monitored. Some of the cylinders were allowed to blow and others were shot by snipers. It was observed that shooting hot cylinders has never created more dangerous situations than letting the cylinders to explode spontaneously. In a great majority of cases cylinders that were punctured by bullets released gas in a more or less violent but relatively safe way. The paper presents detailed information about experiments and presents particularities of behavior of cylinders containing different gases. Extensive research was also done in order to select bullets that may be safely and efficiently used to puncture different cylinders. The paper shows also results of those experiments as well as gives practical information related to techniques that should be used during shooting.

Keywords: fire, gas cylinders, neutralization, shooting

Procedia PDF Downloads 250
5550 Finite Element Analysis of the Lumbar Spine after Unilateral and Bilateral Laminotomies and Laminectomy

Authors: Chih-Hsien Chen, Yi-Hung Ho, Chih-Wei Wang, Chih-Wei Chang, Yen-Nien Chen, Chih-Han Chang, Chun-Ting Li

Abstract:

Laminotomy is a spinal decompression surgery compatible with a minimally invasive approach. However, the unilateral laminotomy for bilateral side decompression leads to more perioperative complications than the bilateral laminotomy. Although the unilateral laminotomy removes the least bone tissue among the spinal decompression surgeries, the difference of spinal stability between unilateral and bilateral laminotomy and laminectomy is rarely investigated. This study aims to compare the biomechanical effects of unilateral and bilateral laminotomy and laminectomy on the lumbar spine by finite element (FE) simulation. A three-dimensional FE model of the lumbar spine (L1–L5) was constructed with the vertebral body, discs, and ligaments, as well as the sacrum was constructed. Three different surgical methods, namely unilateral laminotomy, bilateral laminotomy and laminectomy, at L3–L4 and L4–L5 were considered. Partial pedicle and entire ligamentum flavum were removed to simulate bilateral decompression in laminotomy. The entire lamina and spinal processes from the lower L3 to upper L5 were detached in the laminectomy model. Then, four kinds of loadings, namely flexion, extension, lateral bending and rotation, were applied on the lumbar with various decompression conditions. The results indicated that the bilateral and unilateral laminotomy both increased the range of motion (ROM) compared with intact lumbar, while the laminectomy increased more ROM than both laminotomy did. The difference of ROM between the bilateral and unilateral laminotomy was very minor. Furthermore, bilateral laminotomy demonstrated similar poster element stress with unilateral laminotomy. Unilateral and bilateral laminotomy are equally suggested to bilateral decompression of lumbar spine with minimally invasive technique because limited effect was aroused due to more bone remove in the bilateral laminotomy on the lumbar stability. Furthermore, laminectomy is the last option for lumbar decompression.

Keywords: minimally invasive technique, lumbar decompression, laminotomy, laminectomy, finite element method

Procedia PDF Downloads 171
5549 Typical Characteristics and Compositions of Solvent System in Application of Maceration Technology to Isolate Antioxidative Activated Extract of Natural Products

Authors: Yohanes Buang, Suwari

Abstract:

Increasing interest of society in use and creation of herbal medicines has encouraged scientists/researchers to establish an ideal method to produce the best quality and quantity of pharmaceutical extracts. To have highest the antioxidative extracts, the method used must be at optimum conditions. Hence, the best method is not only able to provide highest quantity and quality of the isolated pharmaceutical extracts but also it has to be easy to do, simple, fast, and cheap. The characterization of solvents in maceration technique, in present study, involved various variables influencing quantity and quality of the pharmaceutical extracts, such as solvent’s optimum acidity-alkalinity (pH), temperature, concentration, and contact time. The shifting polarity of the solvent by combinations of water with ethanol (70:30) and (50:50) were also performed to completely record the best solvent system in application of maceration technology. Among those three solvents threated within Myrmecodia pendens, as a model of natural product, the results showed that water solvent system with conditions of alkalinity pH, optimum temperature, concentration, and contact time, is the best system to perform the maceration in order to have the highest isolated antioxidative activated extracts. The optimum conditions of the water solvent are at the alkalinity pH 9 up, 30 mg/mL of concentration, 40 min of contact time, 100 °C of temperature, and no ethanol used to replace parts of the water solvent. The present study strongly recommended the best conditions of solvent system to isolate the pharmaceutical extracts of natural products in application of the maceration technology.

Keywords: extracts, herbal medicine, natural product, maceration technique

Procedia PDF Downloads 286
5548 Tasting Terroir: A Gourmet Adventure in Food and Wine Tourism

Authors: Sunita Boro, Saurabh Kumar Dixit

Abstract:

Terroir, an intricate fusion of geography, climate, soil, and human expertise, has long been acknowledged as a defining factor in the character of wines and foods. This research embarks on an exploration of terroir's profound influence on gastronomic tourism, shedding light on the intricate interplay between the physical environment and culinary artistry. Delving into the intricate science of terroir, we scrutinize its role in shaping the sensory profiles of wines and foods, emphasizing the profound impact of specific regions on flavor, aroma, and texture. We deploy a multifaceted methodology, amalgamating sensory analysis, chemical profiling, geographical information systems, and qualitative interviews to unearth the nuanced nuances of terroir expression. Through an exhaustive review of the literature, we elucidate the historical roots of terroir, unveil the intricate cultural dimensions shaping it, and provide a comprehensive examination of prior studies in the field. Our findings underscore the pivotal role of terroir in promoting regional identities, enhancing the economic viability of locales, and attracting gastronomic tourists. The paper also dissects the marketing strategies employed to promote terroir-driven food and wine experiences. We elucidate the utilization of storytelling, branding, and collaborative endeavors in fostering a robust terroir-based tourism industry. This elucidates both the potential for innovation and the challenges posed by oversimplification or misrepresentation of terroir. Our research spotlights the intersection of terroir and sustainability, emphasizing the significance of environmentally conscious practices in terroir-driven productions. We discern the harmonious relationship between sustainable agriculture, terroir preservation, and responsible tourism, encapsulating the essence of ecological integrity in gastronomic tourism. Incorporating compelling case studies of regions and businesses excelling in the terroir-based tourism realm, we offer in-depth insights into successful models and strategies, with an emphasis on their replicability and adaptability to various contexts. Ultimately, this paper not only contributes to the scholarly understanding of terroir's role in the world of food and wine tourism but also provides actionable recommendations for stakeholders to leverage terroir's allure, preserve its authenticity, and foster sustainable and enriching culinary tourism experiences.

Keywords: terroir, food tourism, wine tourism, sustainability

Procedia PDF Downloads 46
5547 Permeability Prediction Based on Hydraulic Flow Unit Identification and Artificial Neural Networks

Authors: Emad A. Mohammed

Abstract:

The concept of hydraulic flow units (HFU) has been used for decades in the petroleum industry to improve the prediction of permeability. This concept is strongly related to the flow zone indicator (FZI) which is a function of the reservoir rock quality index (RQI). Both indices are based on reservoir porosity and permeability of core samples. It is assumed that core samples with similar FZI values belong to the same HFU. Thus, after dividing the porosity-permeability data based on the HFU, transformations can be done in order to estimate the permeability from the porosity. The conventional practice is to use the power law transformation using conventional HFU where percentage of error is considerably high. In this paper, neural network technique is employed as a soft computing transformation method to predict permeability instead of power law method to avoid higher percentage of error. This technique is based on HFU identification where Amaefule et al. (1993) method is utilized. In this regard, Kozeny and Carman (K–C) model, and modified K–C model by Hasan and Hossain (2011) are employed. A comparison is made between the two transformation techniques for the two porosity-permeability models. Results show that the modified K-C model helps in getting better results with lower percentage of error in predicting permeability. The results also show that the use of artificial intelligence techniques give more accurate prediction than power law method. This study was conducted on a heterogeneous complex carbonate reservoir in Oman. Data were collected from seven wells to obtain the permeability correlations for the whole field. The findings of this study will help in getting better estimation of permeability of a complex reservoir.

Keywords: permeability, hydraulic flow units, artificial intelligence, correlation

Procedia PDF Downloads 121
5546 Enzymatic Repair Prior To DNA Barcoding, Aspirations, and Restraints

Authors: Maxime Merheb, Rachel Matar

Abstract:

Retrieving ancient DNA sequences which in return permit the entire genome sequencing from fossils have extraordinarily improved in recent years, thanks to sequencing technology and other methodological advances. In any case, the quest to search for ancient DNA is still obstructed by the damage inflicted on DNA which accumulates after the death of a living organism. We can characterize this damage into three main categories: (i) Physical abnormalities such as strand breaks which lead to the presence of short DNA fragments. (ii) Modified bases (mainly cytosine deamination) which cause errors in the sequence due to an incorporation of a false nucleotide during DNA amplification. (iii) DNA modifications referred to as blocking lesions, will halt the PCR extension which in return will also affect the amplification and sequencing process. We can clearly see that the issues arising from breakage and coding errors were significantly decreased in recent years. Fast sequencing of short DNA fragments was empowered by platforms for high-throughput sequencing, most of the coding errors were uncovered to be the consequences of cytosine deamination which can be easily removed from the DNA using enzymatic treatment. The methodology to repair DNA sequences is still in development, it can be basically explained by the process of reintroducing cytosine rather than uracil. This technique is thus restricted to amplified DNA molecules. To eliminate any type of damage (particularly those that block PCR) is a process still pending the complete repair methodologies; DNA detection right after extraction is highly needed. Before using any resources into extensive, unreasonable and uncertain repair techniques, it is vital to distinguish between two possible hypotheses; (i) DNA is none existent to be amplified to begin with therefore completely un-repairable, (ii) the DNA is refractory to PCR and it is worth to be repaired and amplified. Hence, it is extremely important to develop a non-enzymatic technique to detect the most degraded DNA.

Keywords: ancient DNA, DNA barcodong, enzymatic repair, PCR

Procedia PDF Downloads 392
5545 Effect of Segregation on the Reaction Rate of Sewage Sludge Pyrolysis in a Bubbling Fluidized Bed

Authors: A. Soria-Verdugo, A. Morato-Godino, L. M. García-Gutiérrez, N. García-Hernando

Abstract:

The evolution of the pyrolysis of sewage sludge in a fixed and a fluidized bed was analyzed using a novel measuring technique. This original measuring technique consists of installing the whole reactor over a precision scale, capable of measuring the mass of the complete reactor with enough precision to detect the mass released by the sewage sludge sample during its pyrolysis. The inert conditions required for the pyrolysis process were obtained supplying the bed with a nitrogen flowrate, and the bed temperature was adjusted to either 500 ºC or 600 ºC using a group of three electric resistors. The sewage sludge sample was supplied through the top of the bed in a batch of 10 g. The measurement of the mass released by the sewage sludge sample was employed to determine the evolution of the reaction rate during the pyrolysis, the total amount of volatile matter released, and the pyrolysis time. The pyrolysis tests of sewage sludge in the fluidized bed were conducted using two different bed materials of the same size but different densities: silica sand and sepiolite particles. The higher density of silica sand particles induces a flotsam behavior for the sewage sludge particles which move close to the bed surface. In contrast, the lower density of sepiolite produces a neutrally-buoyant behavior for the sewage sludge particles, which shows a proper circulation throughout the whole bed in this case. The analysis of the evolution of the pyrolysis process in both fluidized beds show that the pyrolysis is faster when buoyancy effects are negligible, i.e. in the bed conformed by sepiolite particles. Moreover, sepiolite was found to show an absorbent capability for the volatile matter released during the pyrolysis of sewage sludge.

Keywords: bubbling fluidized bed, pyrolysis, reaction rate, segregation effects, sewage sludge

Procedia PDF Downloads 342