Search results for: process design
Commenced in January 2007
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Edition: International
Paper Count: 24312

Search results for: process design

16272 An Application of Vector Error Correction Model to Assess Financial Innovation Impact on Economic Growth of Bangladesh

Authors: Md. Qamruzzaman, Wei Jianguo

Abstract:

Over the decade, it is observed that financial development, through financial innovation, not only accelerated development of efficient and effective financial system but also act as a catalyst in the economic development process. In this study, we try to explore insight about how financial innovation causes economic growth in Bangladesh by using Vector Error Correction Model (VECM) for the period of 1990-2014. Test of Cointegration confirms the existence of a long-run association between financial innovation and economic growth. For investigating directional causality, we apply Granger causality test and estimation explore that long-run growth will be affected by capital flow from non-bank financial institutions and inflation in the economy but changes of growth rate do not have any impact on Capital flow in the economy and level of inflation in long-run. Whereas, growth and Market capitalization, as well as market capitalization and capital flow, confirm feedback hypothesis. Variance decomposition suggests that any innovation in the financial sector can cause GDP variation fluctuation in both long run and short run. Financial innovation promotes efficiency and cost in financial transactions in the financial system, can boost economic development process. The study proposed two policy recommendations for further development. First, innovation friendly financial policy should formulate to encourage adaption and diffusion of financial innovation in the financial system. Second, operation of financial market and capital market should be regulated with implementation of rules and regulation to create conducive environment.

Keywords: financial innovation, economic growth, GDP, financial institution, VECM

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16271 Programmable Microfluidic Device Based on Stimuli Responsive Hydrogels

Authors: Martin Elstner

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Processing of information by means of handling chemicals is a ubiquitous phenomenon in nature. Technical implementations of chemical information processing lack of low integration densities compared to electronic devices. Stimuli responsive hydrogels are promising candidates for materials with information processing capabilities. These hydrogels are sensitive toward chemical stimuli like metal ions or amino acids. The binding of an analyte molecule induces conformational changes inside the polymer network and subsequently the water content and volume of the hydrogel varies. This volume change can control material flows, and concurrently information flows, in microfluidic devices. The combination of this technology with powerful chemical logic gates yields in a platform for highly integrated chemical circuits. The manufacturing process of such devices is very challenging and rapid prototyping is a key technology used in the study. 3D printing allows generating three-dimensional defined structures of high complexity in a single and fast process step. This thermoplastic master is molded into PDMS and the master is removed by dissolution in an organic solvent. A variety of hydrogel materials is prepared by dispenser printing of pre-polymer solutions. By a variation of functional groups or cross-linking units, the functionality of the hole circuit can be programmed. Finally, applications in the field of bio-molecular analytics were demonstrated with an autonomously operating microfluidic chip.

Keywords: bioanalytics, hydrogels, information processing, microvalve

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16270 Correlation of P53 Gene Expression With Serum Alanine Transaminase Levels and Hepatitis B Viral Load in Cirrhosis and Hepatocellular Carcinoma Patients

Authors: Umme Shahera, Saifullah Munshi, Munira Jahan, Afzalun Nessa, Shahinul Alam, Shahina Tabassum

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The development of HCC is a multi-stage process. Several extrinsic factors, such as aflatoxin, HBV, nutrition, alcohol, and trace elements are thought to initiate or/and promote the hepatocarcinogenesis. Alteration of p53 status is an important intrinsic factor in this process as p53 is essential for preventing inappropriate cell proliferation and maintaining genome integrity following genotoxic stress. This study was designed to assess the correlation of p53 gene expression with HBV-DNA and serum Alanine transaminase (ALT) in patients with cirrhosis and HCC. The study was conducted among 60 patients. The study population were divided into four groups (15 in each groups)-HBV positive cirrhosis, HBV negative cirrhosis, HBV positive HCC and HBV negative HCC. Expression of p53 gene was observed using real time PCR. P53 gene expressions in the above mentioned groups were correlated with serum ALT level and HBV viral load. p53 gene was significantly higher in HBV-positive patients with HCC than HBV-positive cirrhosis. Similarly, the expression of p53 was significantly higher in HBV-positive HCC than HBV-negative HCC patients. However, the expression of p53 was reduced in HBV-positive cirrhosis in comparison with HBV-negative cirrhosis. P53 gene expression in liver was not correlated with the serum levels of ALT in any of the study groups. HBV- DNA load also did not correlated with p53 gene expression in HBV positive HCC and HBV positive cirrhosis patients. This study shows that there was no significant change with the expression of p53 gene in any of the study groups with ALT level or viral load, though differential expression of p53 gene were observed in cirrhosis and HCC patients.

Keywords: P53, ALT, HBV-DNA, liver cirrhosis, hepatocellular carcinoma

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16269 The Messy and Irregular Experience of Entrepreneurial Life

Authors: Hannah Dean

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The growth ideology, and its association with progress, is an important construct in the narrative of modernity. This ideology is embedded in neoclassical economic growth theory which conceptualises growth as linear and predictable, and the entrepreneur as a rational economic manager. This conceptualisation has been critiqued for reinforcing the managerial discourse in entrepreneurship studies. Despite these critiques, both the neoclassical growth theory and its adjacent managerial discourse dominate entrepreneurship studies notably the literature on female entrepreneurs. The latter is the focus of this paper. Given this emphasis on growth, female entrepreneurs are portrayed as problematic because their growth lags behind their male counterparts. This image which ignores the complexity and diversity of female entrepreneurs’ experience persists in the literature due to the lack of studies that analyse the process and contextual factors surrounding female entrepreneurs’ experience. This study aims to address the subordination of female entrepreneurs by questioning the hegemonic logic of economic growth and the managerial discourse as a true representation for the entrepreneurial experience. This objective is achieved by drawing on Schumpeter’s theorising and narrative inquiry. This exploratory study undertakes in depth interviews to gain insights into female entrepreneurs’ experience and the impact of the economic growth model and the managerial discourse on their performance. The narratives challenge a number of assumptions about female entrepreneurs. The participants occupied senior positions in the corporate world before setting up their businesses. This is at odds with much writing which assumes that women underperform because they leave their career without gaining managerial experience to achieve work-life balance. In line with Schumpeter, who distinguishes the entrepreneur from the manager, the participants’ main function was innovation. They did not believe that the managerial paradigm governing their corporate careers was applicable to their entrepreneurial experience. Formal planning and managerial rationality can hinder their decision making process. The narratives point to the gap between the two worlds which makes stepping into entrepreneurship a scary move. Schumpeter argues that the entrepreneurial process is evolutionary and that failure is an integral part of it. The participants’ entrepreneurial process was in fact irregular. The performance of new combinations was not always predictable. They therefore relied on their initiative. The inhibition to deploy these traits had an adverse effect on business growth. The narratives also indicate that over-reliance on growth threaten the business survival as it faces competing pressures. The study offers theoretical and empirical contributions to (female) entrepreneurship studies by presenting Schumpeter’s theorising as an alternative theoretical framework to the neoclassical economic growth theory. The study also reduces entrepreneurs’ vulnerability by making them aware of the negative influence that the linear growth model and the managerial discourse hold upon their performance. The study has implications for policy makers as it generates new knowledge that incorporates the current social and economic changes in the context of entrepreneurs that can no longer be sustained by the linear growth models especially in the current economic climate.

Keywords: economic growth, female entrepreneurs, managerial discourse, Schumpeter

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16268 Handling, Exporting and Archiving Automated Mineralogy Data Using TESCAN TIMA

Authors: Marek Dosbaba

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Within the mining sector, SEM-based Automated Mineralogy (AM) has been the standard application for quickly and efficiently handling mineral processing tasks. Over the last decade, the trend has been to analyze larger numbers of samples, often with a higher level of detail. This has necessitated a shift from interactive sample analysis performed by an operator using a SEM, to an increased reliance on offline processing to analyze and report the data. In response to this trend, TESCAN TIMA Mineral Analyzer is designed to quickly create a virtual copy of the studied samples, thereby preserving all the necessary information. Depending on the selected data acquisition mode, TESCAN TIMA can perform hyperspectral mapping and save an X-ray spectrum for each pixel or segment, respectively. This approach allows the user to browse through elemental distribution maps of all elements detectable by means of energy dispersive spectroscopy. Re-evaluation of the existing data for the presence of previously unconsidered elements is possible without the need to repeat the analysis. Additional tiers of data such as a secondary electron or cathodoluminescence images can also be recorded. To take full advantage of these information-rich datasets, TIMA utilizes a new archiving tool introduced by TESCAN. The dataset size can be reduced for long-term storage and all information can be recovered on-demand in case of renewed interest. TESCAN TIMA is optimized for network storage of its datasets because of the larger data storage capacity of servers compared to local drives, which also allows multiple users to access the data remotely. This goes hand in hand with the support of remote control for the entire data acquisition process. TESCAN also brings a newly extended open-source data format that allows other applications to extract, process and report AM data. This offers the ability to link TIMA data to large databases feeding plant performance dashboards or geometallurgical models. The traditional tabular particle-by-particle or grain-by-grain export process is preserved and can be customized with scripts to include user-defined particle/grain properties.

Keywords: Tescan, electron microscopy, mineralogy, SEM, automated mineralogy, database, TESCAN TIMA, open format, archiving, big data

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16267 Factors Affecting Ethical Leadership and Employee Affective Organizational Commitment: An Empirical Study

Authors: Sharmin Shahid, Zaher Zain

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The purpose of this study is to explore and examines the theoretical frameworks of ethical leadership style and affective organizational commitment. Additionally, to investigate the extent to which employee orientation and ethical guidance either strengthen or weaken on the relationship between ethical leadership style and affective commitment. The study will also measure the mediating effects of leader’s integrity either influence to inspire and revival employee’s affective commitment or not. The methodology of the study comprised sample of 237 managers, departmental heads, top-level executives, and professors of several financial institutions, banks, and universities in Bangladesh who are directly related with decision making process of respective organization. A cross sectional research design will be used to examine the direct, moderating, and mediating analysis among the research key variables. Data were gathered based on personal administered questionnaire. The findings of the study will be significance because it will provide the real scenario of leadership style which leads to financial and strategic success of any organizations. In addition, the results will be interesting enough to find out either ethical leadership style have positive relationship with affective commitment or not. Employee-orientation and ethical guidance is a moderator to improve leadership style and affective commitment, whereas, leader’s integrity mediates the relationships between leadership style and affective organizational commitment to do the right thing in the right way for the betterment of entire organizational success. Research limitations of the study are the data collected by self administered questionnaire, a method with well-known shortcomings. Second, the study concentrated on financial institutions, banks top executives, and universities professors in Bangladesh. An important implication of the research is that the interesting findings will give some insight to the leadership style and helps management to focus on their management and leadership efficacy, as that could improve their affective organizational commitment. The findings will be original and unique value adding with the existing literature on leadership studies. The study is based on a comprehensive literature review. The results will be based on a sample of financial institutions, banks, and universities in Bangladesh. The research findings are useful to academics and corporate leaders of financial institutions, banks, and universities all over the world.

Keywords: affective organizational commitment, Bangladesh, ethical guidance, ethical leadership style

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16266 Modelling Biological Treatment of Dye Wastewater in SBR Systems Inoculated with Bacteria by Artificial Neural Network

Authors: Yasaman Sanayei, Alireza Bahiraie

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This paper presents a systematic methodology based on the application of artificial neural networks for sequencing batch reactor (SBR). The SBR is a fill-and-draw biological wastewater technology, which is specially suited for nutrient removal. Employing reactive dye by Sphingomonas paucimobilis bacteria at sequence batch reactor is a novel approach of dye removal. The influent COD, MLVSS, and reaction time were selected as the process inputs and the effluent COD and BOD as the process outputs. The best possible result for the discrete pole parameter was a= 0.44. In orderto adjust the parameters of ANN, the Levenberg-Marquardt (LM) algorithm was employed. The results predicted by the model were compared to the experimental data and showed a high correlation with R2> 0.99 and a low mean absolute error (MAE). The results from this study reveal that the developed model is accurate and efficacious in predicting COD and BOD parameters of the dye-containing wastewater treated by SBR. The proposed modeling approach can be applied to other industrial wastewater treatment systems to predict effluent characteristics. Note that SBR are normally operated with constant predefined duration of the stages, thus, resulting in low efficient operation. Data obtained from the on-line electronic sensors installed in the SBR and from the control quality laboratory analysis have been used to develop the optimal architecture of two different ANN. The results have shown that the developed models can be used as efficient and cost-effective predictive tools for the system analysed.

Keywords: artificial neural network, COD removal, SBR, Sphingomonas paucimobilis

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16265 The Effect of the Archeological and Architectural Nature of the Cities on the Design of Public Transportation Vehicles

Authors: Mohamed Moheyeldin Mahmoud

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Various Islamic, Coptic and Jewish archeological places are located in many Egyptian neighborhoods such as Alsayeda zainab, Aldarb Alahmar, Algammaleya and many other in which they are daily exposed to a great traffic intensity causing vibrations. Vibrations could be stated as one of the most important challenges that face the archeological buildings and threaten their survival. The impact of vibrations varies according to the nature of the soil, nature and building conditions, how far the source of vibration is and the period of exposure. Traffic vibrations could be also stated as one of the most common types of vibrations having the greatest impact on buildings and archaeological installations. These vibrations result from the way that the vehicles act with different types of roads which vary according to the shape, nature, and type of obstacles. Other elements concerning the vehicle itself such as speed, weight, and load have a direct impact on the vibrations resulting from the vehicle movement that couldn't be neglected. The research aims to determine some of the requirements that must be observed when designing the public means of transport operating in the archaeological areas, in order to preserve the archaeological nature of the place. The research concludes that light weight slow motion vehicles should be used (25-50 km/h at maximum) having a multi-leaf steel spring suspension system instead of having an air-bag one should be used in order to reduce generated vibrations that could destroy the archeological buildings. Isolation layers could be used in the engine chamber in order to reduce the resulting noise causing vibrations. Electrically operated engines that use solar photovoltaic cells as a source of electricity could be used instead of gas ones in order to reduce the resulting engine noise.

Keywords: archeological, design, isolation layers, suspension, vibrations

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16264 A Case Study on Evaluating and Selecting Soil /Pipeline Interaction Analysis Software for the Oil and Gas Industry

Authors: Abdinasir Mohamed, Ashraf El-Hamalawi, Steven Yeomans, Matthew Frost, Andy Connell

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The evaluation and selection of appropriate software solutions to meet with an organisation’s inherent business requirements can be a problematic software engineering process that if done incorrectly can have a significant, costly and adverse effect on the business and its processes. The aim of this paper is to show the process and evaluation criteria followed to select the right engineering solution for the identified business requirement. The research adopted an action research method within an organisation in the oil and gas industry, which required a solution suitable for conducting stress analysis for soil-pipeline interaction analysis (SPIA). Through the use of the presented software selection and evaluation approach, to capture and measure key requirements, it was possible to determine a suitable software for the organisation. This paper investigates methodologies for selecting software packages, software evaluation techniques, and software evaluation criteria in evaluating software packages before providing an explanation of the developed methodology adopted. The key findings of the study are: (1) that there is a need to create a framework for software selection methodologies, (2) there are no universal selection criteria in the engineering industry, and (3) there is a need to validate the findings by creating an application based on the evaluation technique and evaluation criteria for selecting software packages for the engineering industry. The findings of the study are offered to support organisations in the oil and gas sector improve software selection methodologies for SPIA.

Keywords: software evaluation, end user programs, soil pipeline analysis, software selection

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16263 Knowledge, Attitudes, and Practices regarding Anthrax among Community Members, Health and Veterinary Workers in Maragua, Kenya

Authors: Isaiah Chacha, Samuel Arimi, Andrew Thaiya

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Background: This study was conducted to assess knowledge, attitudes and practices regarding anthrax in Maragua, Kenya to provide baseline information to design interventions. Methods: A cross sectional survey was conducted among head of households, health and veterinary workers in Maragua Sub-county in August and September 2014. Administered questionnaires were used to collect data from household members and a key informant interview held with health and veterinary workers. Multi stage sampling was used to obtain participants’ knowledge, attitudes and practices. Questions were scored and descriptively analyzed using Excel spreadsheet then exported to GenStat Discovery Edition 4. Results: A total of 293 community members were recruited in this study. The overall level of knowledge was 77.9% of all community members regarding cause, transmission, symptoms and prevention of the disease in both humans and animals. Majority of the participants (96.3%) had heard about anthrax. A total of 99 (33.8%) correspondents had seen a person with anthrax and 75.1% think that anthrax is a very serious disease in the area. Of the interviewed correspondents, 14.3% of them have had their animals (mostly cattle) suffer from anthrax while 15.7% had either suffered from anthrax or have had their family member who suffered from anthrax. Conclusion: The study findings indicate above average knowledge on cause, symptoms, transmission and prevention of anthrax among community members in humans and animals. Practices in this study were still risk among community members. Veterinary and Medical health planners should design anthrax awareness interventions as a team targeting to reach these communities and the public through barazas, radio, CHW and other communication channel on a regular basis.

Keywords: anthrax, attitudes, Kenya, knowledge, Maragua, practices

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16262 Experimental and Theoretical Investigation of Slow Reversible Deformation of Concrete in Surface-Active Media

Authors: Nika Botchorishvili, Olgha Giorgishvili

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Many-year investigations of the nature of damping creep of rigid bodies and materials led to the discovery of the fundamental character of this phenomenon. It occurs only when a rigid body comes in contact with a surface-active medium (liquid or gaseous), which brings about a decrease of the free surface energy of a rigid body as a result of adsorption, chemo-sorption or wetting. The reversibility of the process consists of a gradual disappearance of creep deformation when the action of a surface-active medium stops. To clarify the essence of processes, a physical model is constructed by using Griffith’s scheme and the well-known representation formulas of deformation origination and failure processes. The total creep deformation is caused by the formation and opening of microcracks throughout the material volume under the action of load. This supposedly happens in macroscopically homogeneous silicate and organic glasses, while in polycrystals (tuff, gypsum, steel) contacting with a surface-active medium micro crack are formed mainly on the grain boundaries. The creep of rubber is due to its swelling activated by stress. Acknowledgment: All experiments are financially supported by Shota Rustaveli National Science Foundation of Georgia. Study of Properties of Concretes (Both Ordinary and Compacted) Made of Local Building Materials and Containing Admixtures, and Their Further Introduction in Construction Operations and Road Building. DP2016_26. 22.12.2016.

Keywords: process reversibility, surface-active medium, Rebinder’s effect, micro crack, creep

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16261 Integrating Explicit Instruction and Problem-Solving Approaches for Efficient Learning

Authors: Slava Kalyuga

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There are two opposing major points of view on the optimal degree of initial instructional guidance that is usually discussed in the literature by the advocates of the corresponding learning approaches. Using unguided or minimally guided problem-solving tasks prior to explicit instruction has been suggested by productive failure and several other instructional theories, whereas an alternative approach - using fully guided worked examples followed by problem solving - has been demonstrated as the most effective strategy within the framework of cognitive load theory. An integrated approach discussed in this paper could combine the above frameworks within a broader theoretical perspective which would allow bringing together their best features and advantages in the design of learning tasks for STEM education. This paper represents a systematic review of the available empirical studies comparing the above alternative sequences of instructional methods to explore effects of several possible moderating factors. The paper concludes that different approaches and instructional sequences should coexist within complex learning environments. Selecting optimal sequences depends on such factors as specific goals of learner activities, types of knowledge to learn, levels of element interactivity (task complexity), and levels of learner prior knowledge. This paper offers an outline of a theoretical framework for the design of complex learning tasks in STEM education that would integrate explicit instruction and inquiry (exploratory, discovery) learning approaches in ways that depend on a set of defined specific factors.

Keywords: cognitive load, explicit instruction, exploratory learning, worked examples

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16260 Design Charts for Strip Footing on Untreated and Cement Treated Sand Mat over Underlying Natural Soft Clay

Authors: Sharifullah Ahmed, Sarwar Jahan Md. Yasin

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Shallow foundations on unimproved soft natural soils can undergo a high consolidation and secondary settlement. For low and medium rise building projects on such soil condition, pile foundation may not be cost effective. In such cases an alternative to pile foundations may be shallow strip footings placed on a double layered improved soil system soil. The upper layer of this system is untreated or cement treated compacted sand and underlying layer is natural soft clay. This system will reduce the settlement to an allowable limit. The current research has been conducted with the settlement of a rigid plane-strain strip footing of 2.5 m width placed on the surface of a soil consisting of an untreated or cement treated sand layer overlying a bed of homogeneous soft clay. The settlement of the mentioned shallow foundation has been studied considering both cases with the thicknesses of the sand layer are 0.3 to 0.9 times the width of footing. The response of the clay layer is assumed as undrained for plastic loading stages and drained during consolidation stages. The response of the sand layer is drained during all loading stages. FEM analysis was done using PLAXIS 2D Version 8.0. A natural clay deposit of 15 m thickness and 18 m width has been modeled using Hardening Soil Model, Soft Soil Model, Soft Soil Creep Model, and upper improvement layer has been modeled using only Hardening Soil Model. The groundwater level is at the top level of the clay deposit that made the system fully saturated. Parametric study has been conducted to determine the effect of thickness, density, cementation of the sand mat and density, shear strength of the soft clay layer on the settlement of strip foundation under the uniformly distributed vertical load of varying value. A set of the chart has been established for designing shallow strip footing on the sand mat over thick, soft clay deposit through obtaining the particular thickness of sand mat for particular subsoil parameter to ensure no punching shear failure and no settlement beyond allowable level. Design guideline in the form of non-dimensional charts has been developed for footing pressure equivalent to medium-rise residential or commercial building foundation with strip footing on soft inorganic Normally Consolidated (NC) soil of Bangladesh having void ratio from 1.0 to 1.45.

Keywords: design charts, ground improvement, PLAXIS 2D, primary and secondary settlement, sand mat, soft clay

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16259 Creep Behaviour of Heterogeneous Timber-UHPFRC Beams Assembled by Bonding: Experimental and Analytical Investigation

Authors: K. Kong, E. Ferrier, L. Michel

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The purpose of this research was to investigate the creep behaviour of the heterogeneous Timber-UHPFRC beams. New developments have been done to further improve the structural performance, such as strengthening of the timber (glulam) beam by bonding composite material combine with an ultra-high performance fibre reinforced concrete (UHPFRC) internally reinforced with or without carbon fibre reinforced polymer (CFRP) bars. However, in the design of wooden structures, in addition to the criteria of strengthening and stiffness, deformability due to the creep of wood, especially in horizontal elements, is also a design criterion. Glulam, UHPFRC and CFRP may be an interesting composite mix to respond to the issue of creep behaviour of composite structures made of different materials with different rheological properties. In this paper, we describe an experimental and analytical investigation of the creep performance of the glulam-UHPFRC-CFRP beams assembled by bonding. The experimental investigations creep behaviour was conducted for different environments: in- and outside under constant loading for approximately a year. The measured results are compared with numerical ones obtained by an analytical model. This model was developed to predict the creep response of the glulam-UHPFRC-CFRP beams based on the creep characteristics of the individual components. The results show that heterogeneous glulam-UHPFRC beams provide an improvement in both the strengthening and stiffness, and can also effectively reduce the creep deflection of wooden beams.

Keywords: carbon fibre-reinforced polymer (CFRP) bars, creep behaviour, glulam, ultra-high performance fibre reinforced concrete (UHPFRC)

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16258 Design and Construction of a Device to Facilitate the Stretching of a Plantiflexors Muscles in the Therapy of Rehabilitation for Patients with Spastic Hemiplegia

Authors: Nathalia Andrea Calderon Lesmes, Eduardo Barragan Parada, Diego Fernando Villegas Bermudez

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Spasticity in the plantiflexor muscles as a product of stroke (CVA-Cerebrovascular accident) restricts the mobility and independence of the affected people. Commonly, physiotherapists are in charge of manually performing the rehabilitation therapy known as Sustained Mechanical Stretching, rotating the affected foot of the patient in the sagittal plane. However, this causes a physical wear on the professional because it is a fatiguing movement. In this article, a mechanical device is developed to implement this rehabilitation therapy more efficiently. The device consists of a worm-crown mechanism that is driven by a crank to gradually rotate a platform in the sagittal plane of the affected foot, in order to achieve dorsiflexion. The device has a range of sagittal rotation up to 150° and has velcro located on the footplate that secures the foot. The design of this device was modeled by using CAD software and was checked structurally with a general purpose finite element software to be sure that the device is safe for human use. As a measurement system, a goniometer is used in the lateral part of the device and load cells are used to measure the force in order to determine the opposing torque exerted by the muscle. Load cells sensitivity is 1.8 ± 0.002 and has a repeatability of 0.03. Validation of the effectiveness of the device is measured by reducing the opposition torque and increasing mobility for a given patient. In this way, with a more efficient therapy, an improvement in the recovery of the patient's mobility and therefore in their quality of life can be achieved.

Keywords: biomechanics, mechanical device, plantiflexor muscles, rehabilitation, spastic hemiplegia, sustained mechanical stretching

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16257 Delivering Comprehensive Sexuality Education to Students with Disability in Special Schools in Fiji

Authors: Sera Ratu, Jane Chivers, Jessica Botfield

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Objectives: The Reproductive and Family Health Association of Fiji (RFHAF) and Family Planning Australia are working together to introduce quality comprehensive sexuality education into Special Schools - which are schools for students with disability. Sexual and reproductive health information is needed by students with disability attending Special Schools. Children with special needs go through the same changes as able-bodied children. The Fiji Disability Inclusion project is a three-year project that started in 2015. One of its objectives is to increase exposure to comprehensive sexuality education for primary and secondary school students with disability. Method: A baseline survey was undertaken with 72 students with disability; it included questions about puberty, sexual health, and relationships. 34 teachers also completed a survey about their views of sexuality education and confidence in delivering it. Consent was facilitated by running information sessions with teachers and parents. The process of gaining consent and completing the surveys was designed to be accessible to students with disability. Given the sensitive nature of reproductive and sexual health, and the potential vulnerability of young people with disability, ethical considerations were important in the design and implementation of the surveys, and ethics approval was obtained. Results: Findings from the surveys suggest that students have mixed knowledge and awareness of sexual health issues. Most teachers reported a need for their students to learn about sexuality and relationships. A positive outcome of conducting the surveys was that RFHAF staff reported they have developed skills and confidence in communicating with young people with a range of disabilities. They have a greater understanding of what students want to learn, and what teachers feel is important. Conclusions: These survey findings will assist RFHAF in developing comprehensive sexuality education programs that are relevant and accessible to students in Special Schools, and to develop an appropriate professional development program for teachers. Findings may also be applicable to other Special Schools when developing sexuality education programs. The education programs developed for students as part of this project, and the professional development programs for teachers, may be relevant to other countries.

Keywords: comprehensive sexuality education, delivery, sexual and reproductive health and rights, special schools

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16256 Non-Methane Hydrocarbons Emission during the Photocopying Process

Authors: Kiurski S. Jelena, Aksentijević M. Snežana, Kecić S. Vesna, Oros B. Ivana

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The prosperity of electronic equipment in photocopying environment not only has improved work efficiency, but also has changed indoor air quality. Considering the number of photocopying employed, indoor air quality might be worse than in general office environments. Determining the contribution from any type of equipment to indoor air pollution is a complex matter. Non-methane hydrocarbons are known to have an important role of air quality due to their high reactivity. The presence of hazardous pollutants in indoor air has been detected in one photocopying shop in Novi Sad, Serbia. Air samples were collected and analyzed for five days, during 8-hr working time in three-time intervals, whereas three different sampling points were determined. Using multiple linear regression model and software package STATISTICA 10 the concentrations of occupational hazards and micro-climates parameters were mutually correlated. Based on the obtained multiple coefficients of determination (0.3751, 0.2389, and 0.1975), a weak positive correlation between the observed variables was determined. Small values of parameter F indicated that there was no statistically significant difference between the concentration levels of non-methane hydrocarbons and micro-climates parameters. The results showed that variable could be presented by the general regression model: y = b0 + b1xi1+ b2xi2. Obtained regression equations allow to measure the quantitative agreement between the variation of variables and thus obtain more accurate knowledge of their mutual relations.

Keywords: non-methane hydrocarbons, photocopying process, multiple regression analysis, indoor air quality, pollutant emission

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16255 PbLi Activation Due to Corrosion Products in WCLL BB (EU-DEMO) and Its Impact on Reactor Design and Recycling

Authors: Nicole Virgili, Marco Utili

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The design of the Breeding Blanket in Tokamak fusion energy systems has to guarantee sufficient availability in addition to its functions, that are, tritium breeding self-sufficiency, power extraction and shielding (the magnets and the VV). All these function in the presence of extremely harsh operating conditions in terms of heat flux and neutron dose as well as chemical environment of the coolant and breeder that challenge structural materials (structural resistance and corrosion resistance). The movement and activation of fluids from the BB to the Ex-vessel components in a fusion power plant have an important radiological consideration because flowing material can carry radioactivity to safety-critical areas. This includes gamma-ray emission from activated fluid and activated corrosion products, and secondary activation resulting from neutron emission, with implication for the safety of maintenance personnel and damage to electrical and electronic equipment. In addition to the PbLi breeder activation, it is important to evaluate the contribution due to the activated corrosion products (ACPs) dissolved in the lead-lithium eutectic alloy, at different concentration levels. Therefore, the purpose of the study project is to evaluate the PbLi activity utilizing the FISPACT II inventory code. Emphasis is given on how the design of the EU-DEMO WCLL, and potential recycling of the breeder material will be impacted by the activation of PbLi and the associated active corrosion products (ACPs). For this scope the following Computational Tools, Data and Geometry have been considered: • Neutron source: EU-DEMO neutron flux < 1014/cm2/s • Neutron flux distribution in equatorial breeding blanket module (BBM) #13 in the WCLL BB outboard central zone, which is the most activated zone, with the aim to introduce a conservative component utilizing MNCP6. • The recommended geometry model: 2017 EU DEMO CAD model. • Blanket Module Material Specifications (Composition) • Activation calculations for different ACP concentration levels in the PbLi breeder, with a given chemistry in stationary equilibrium conditions, using FISPACT II code. Results suggest that there should be a waiting time of about 10 years from the shut-down (SD) to be able to safely manipulate the PbLi for recycling operations with simple shielding requirements. The dose rate is mainly given by the PbLi and the ACP concentration (x1 or x 100) does not shift the result. In conclusion, the results show that there is no impact on PbLi activation due to ACPs levels.

Keywords: activation, corrosion products, recycling, WCLL BB., PbLi

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16254 Laser Shock Peening of Additively Manufactured Nickel-Based Superalloys

Authors: Michael Munther, Keivan Davami

Abstract:

One significant roadblock for additively manufactured (AM) parts is the buildup of residual tensile stresses during the fabrication process. These residual stresses are formed due to the intense localized thermal gradients and high cooling rates that cause non-uniform material expansion/contraction and mismatched strain profiles during powder-bed fusion techniques, such as direct metal laser sintering (DMLS). The residual stresses adversely affect the fatigue life of the AM parts. Moreover, if the residual stresses become higher than the material’s yield strength, they will lead to acute geometric distortion. These are limiting the applications and acceptance of AM components for safety-critical applications. Herein, we discuss laser shock peening method as an advanced technique for the manipulation of the residual stresses in AM parts. An X-ray diffraction technique is used for the measurements of the residual stresses before and after the laser shock peening process. Also, the hardness of the structures is measured using a nanoindentation technique. Maps of nanohardness and modulus are obtained from the nanoindentation, and a correlation is made between the residual stresses and the mechanical properties. The results indicate that laser shock peening is able to induce compressive residual stresses in the structure that mitigate the tensile residual stresses and increase the hardness of AM IN718, a superalloy, almost 20%. No significant changes were observed in the modulus after laser shock peening. The results strongly suggest that laser shock peening can be used as an advanced post-processing technique to optimize the service lives of critical components for various applications.

Keywords: additive manufacturing, Inconel 718, laser shock peening, residual stresses

Procedia PDF Downloads 111
16253 Real-Time Generative Architecture for Mesh and Texture

Authors: Xi Liu, Fan Yuan

Abstract:

In the evolving landscape of physics-based machine learning (PBML), particularly within fluid dynamics and its applications in electromechanical engineering, robot vision, and robot learning, achieving precision and alignment with researchers' specific needs presents a formidable challenge. In response, this work proposes a methodology that integrates neural transformation with a modified smoothed particle hydrodynamics model for generating transformed 3D fluid simulations. This approach is useful for nanoscale science, where the unique and complex behaviors of viscoelastic medium demand accurate neurally-transformed simulations for materials understanding and manipulation. In electromechanical engineering, the method enhances the design and functionality of fluid-operated systems, particularly microfluidic devices, contributing to advancements in nanomaterial design, drug delivery systems, and more. The proposed approach also aligns with the principles of PBML, offering advantages such as multi-fluid stylization and consistent particle attribute transfer. This capability is valuable in various fields where the interaction of multiple fluid components is significant. Moreover, the application of neurally-transformed hydrodynamical models extends to manufacturing processes, such as the production of microelectromechanical systems, enhancing efficiency and cost-effectiveness. The system's ability to perform neural transfer on 3D fluid scenes using a deep learning algorithm alongside physical models further adds a layer of flexibility, allowing researchers to tailor simulations to specific needs across scientific and engineering disciplines.

Keywords: physics-based machine learning, robot vision, robot learning, hydrodynamics

Procedia PDF Downloads 48
16252 Microbioreactor System for Cell Behavior Analysis Focused on Nerve Tissue Engineering

Authors: Yusser Olguín, Diego Benavente, Fernando Dorta, Nicole Orellana, Cristian Acevedo

Abstract:

One of the greatest challenges of tissue engineering is the generation of materials in which the highest possible number of conditions can be incorporated to stimulate the proliferation and differentiation of cells, which will be transformed together with the material into new functional tissue. In this sense, considering the properties of microfluidics and its relationship with cellular micro-environments, the possibility of controlling flow patterns and the ability to design diverse patterns in the chips, a microfluidic cell culture system can be established as a means for the evaluation of the effect of different parameters in a controlled and precise manner. Specifically in relation to the study and development of alternatives in peripheral nervous tissue engineering, it is necessary to consider different physical and chemical neurotrophic stimuli that promote cell growth and differentiation. Chemical stimuli include certain vitamins, glucocorticoids, gangliosides, and growth factors, while physical stimuli include topological stimuli, mechanical forces of the cellular environment and electrical stimulation. In this context, the present investigation shows the results of cell stimulation in a microbioreactor using electrical and chemical stimuli, where the differentiation of PC12 cells as a neuronal model is evidenced by neurite expression, dependent on the stimuli and their combination. The results were analysed with a multi-factor statistical approach, showing several relationships and dependencies between different parameters. Chip design, operating parameters and concentrations of neurotrophic chemical factors were found to be preponderant, based on the characteristics of the electrical stimuli.

Keywords: microfluidics, nerve tissue engineering, microbioreactor, electrical stimuli

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16251 Design Study on a Contactless Material Feeding Device for Electro Conductive Workpieces

Authors: Oliver Commichau, Richard Krimm, Bernd-Arno Behrens

Abstract:

A growing demand on the production rate of modern presses leads to higher stroke rates. Commonly used material feeding devices for presses like grippers and roll-feeding systems can only achieve high stroke rates along with high gripper forces, to avoid stick-slip. These forces are limited by the sensibility of the surfaces of the workpieces. Stick-slip leads to scratches on the surface and false positioning of the workpiece. In this paper, a new contactless feeding device is presented, which develops higher feeding force without damaging the surface of the workpiece through gripping forces. It is based on the principle of the linear induction motor. A primary part creates a magnetic field and induces eddy currents in the electrically conductive material. A Lorentz-Force applies to the workpiece in feeding direction as a mutual reaction between the eddy-currents and the magnetic induction. In this study, the FEA model of this approach is shown. The calculation of this model was used to identify the influence of various design parameters on the performance of the feeder and thus showing the promising capabilities and limits of this technology. In order to validate the study, a prototype of the feeding device has been built. An experimental setup was used to measure pulling forces and placement accuracy of the experimental feeder in order to give an outlook of a potential industrial application of this approach.

Keywords: conductive material, contactless feeding, linear induction, Lorentz-Force

Procedia PDF Downloads 165
16250 Property of Fermented Sweet Potato Flour and Its Suitability for Composite Noodle

Authors: Neti Yuliana, Srisetyani, Siti Nurdjanah, Dewi Sartika, Yoan Martiansari, Putri Nabila

Abstract:

Naturally sweet potato flour usually requires a modification process to improve its inherent property for expanding its application in food system. The study was aimed to modify sweet potato flour (SPF), to increase its utilization for composite noodle production, trough fermentation of sweet potato slices before its flouring process. Fermentation were prepared with five different starters: pickle brine, Lactobacillus plantarum, Leuconostoc mesenteroides, mixed of Lactobacillus plantarum, Leuconostoc mesenteroides , and mixed of Lactobacillus plantarum, Leuconostoc mesenteroides, and Sacharomyces cerevisiae. Samples were withdrawn every 0, 24, 48, 72 and 96 hours. The fermented flours were characterized for swelling power, solubility, paste transmittance, pH, sensory properties (acidic aroma and whiteness), and the amount of broken composite noodle strips. The results indicated that there was no significant effect of different starters on fermented SPF characteristic and on the amount of broken noodle strip, while length of fermentation significantly affected. Longer fermentation, reaching 48-72 h, increased swelling power, pH, acidic aroma and whiteness of flour and reduced solubility, paste transmittance, and the amount of broken noodle strip. The results suggested that fermentation within 48-72 h period of time could provide great composite SPF for noodle.

Keywords: starters, fermented flour, sweet potato, composite noodle

Procedia PDF Downloads 367
16249 Concept of Using an Indicator to Describe the Quality of Fit of Clothing to the Body Using a 3D Scanner and CAD System

Authors: Monika Balach, Iwona Frydrych, Agnieszka Cichocka

Abstract:

The objective of this research is to develop an algorithm, taking into account material type and body type that will describe the fabric properties and quality of fit of a garment to the body. One of the objectives of this research is to develop a new algorithm to simulate cloth draping within CAD/CAM software. Existing virtual fitting does not accurately simulate fabric draping behaviour. Part of the research into virtual fitting will focus on the mechanical properties of fabrics. Material behaviour depends on many factors including fibre, yarn, manufacturing process, fabric weight, textile finish, etc. For this study, several different fabric types with very different mechanical properties will be selected and evaluated for all of the above fabric characteristics. These fabrics include woven thick cotton fabric which is stiff and non-bending, woven with elastic content, which is elastic and bends on the body. Within the virtual simulation, the following mechanical properties can be specified: shear, bending, weight, thickness, and friction. To help calculate these properties, the KES system (Kawabata) can be used. This system was originally developed to calculate the mechanical properties of fabric. In this research, the author will focus on three properties: bending, shear, and roughness. This study will consider current research using the KES system to understand and simulate fabric folding on the virtual body. Testing will help to determine which material properties have the largest impact on the fit of the garment. By developing an algorithm which factors in body type, material type, and clothing function, it will be possible to determine how a specific type of clothing made from a particular type of material will fit on a specific body shape and size. A fit indicator will display areas of stress on the garment such as shoulders, chest waist, hips. From this data, CAD/CAM software can be used to develop garments that fit with a very high degree of accuracy. This research, therefore, aims to provide an innovative solution for garment fitting which will aid in the manufacture of clothing. This research will help the clothing industry by cutting the cost of the clothing manufacturing process and also reduce the cost spent on fitting. The manufacturing process can be made more efficient by virtual fitting of the garment before the real clothing sample is made. Fitting software could be integrated into clothing retailer websites allowing customers to enter their biometric data and determine how the particular garment and material type would fit their body.

Keywords: 3D scanning, fabric mechanical properties, quality of fit, virtual fitting

Procedia PDF Downloads 161
16248 Sub-Pixel Mapping Based on New Mixed Interpolation

Authors: Zeyu Zhou, Xiaojun Bi

Abstract:

Due to the limited environmental parameters and the limited resolution of the sensor, the universal existence of the mixed pixels in the process of remote sensing images restricts the spatial resolution of the remote sensing images. Sub-pixel mapping technology can effectively improve the spatial resolution. As the bilinear interpolation algorithm inevitably produces the edge blur effect, which leads to the inaccurate sub-pixel mapping results. In order to avoid the edge blur effect that affects the sub-pixel mapping results in the interpolation process, this paper presents a new edge-directed interpolation algorithm which uses the covariance adaptive interpolation algorithm on the edge of the low-resolution image and uses bilinear interpolation algorithm in the low-resolution image smooth area. By using the edge-directed interpolation algorithm, the super-resolution of the image with low resolution is obtained, and we get the percentage of each sub-pixel under a certain type of high-resolution image. Then we rely on the probability value as a soft attribute estimate and carry out sub-pixel scale under the ‘hard classification’. Finally, we get the result of sub-pixel mapping. Through the experiment, we compare the algorithm and the bilinear algorithm given in this paper to the results of the sub-pixel mapping method. It is found that the sub-pixel mapping method based on the edge-directed interpolation algorithm has better edge effect and higher mapping accuracy. The results of the paper meet our original intention of the question. At the same time, the method does not require iterative computation and training of samples, making it easier to implement.

Keywords: remote sensing images, sub-pixel mapping, bilinear interpolation, edge-directed interpolation

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16247 Effective Doping Engineering of Na₃V₂(PO₄)₂F₃ as a High-Performance Cathode Material for Sodium-Ion Batteries

Authors: Ramon Alberto Paredes Camacho, Li Lu

Abstract:

Sustainable batteries are possible through the development of cheaper and greener alternatives whose most feasible option is epitomized by Sodium-Ion Batteries (SIB). Na₃V₂(PO₄)₂F₃ (NVPF) an important member of the Na-superionic-conductor (NASICON) materials, has recently been in the spotlight due to its interesting electrochemical properties when used as cathode namely, high specific capacity of 128 mA h g-¹, high energy density of 507 W h Kg-¹, increased working potential at which vanadium redox couples can be activated (with an average value around 3.9 V), and small volume variation of less than 2%. These traits grant NVPF an excellent perspective as a cathode material for the next generation of sodium batteries. Unfortunately, because of its low inherent electrical conductivity and a high energy barrier that impedes the mobilization of all the available Na ions per formula, the overall electrochemical performance suffers substantial degradation, finally obstructing its industrial use. Many approaches have been developed to remediate these issues where nanostructural design, carbon coating, and ion doping are the most effective ones. This investigation is focused on enhancing the electrochemical response of NVPF by doping metal ions in the crystal lattice, substituting vanadium atoms. A facile sol-gel process is employed, with citric acid as the chelator and the carbon source. The optimized conditions circumvent fluorine sublimation, ratifying the material’s purity. One of the reasons behind the large ionic improvement is the attraction of extra Na ions into the crystalline structure due to a charge imbalance produced by the valence of the doped ions (+2), which is lower than the one of vanadium (+3). Superior stability (higher than 90% at a current density of 20C) and capacity retention at an extremely high current density of 50C are demonstrated by our doped NVPF. This material continues to retain high capacity values at low and high temperatures. In addition, full cell NVPF//Hard Carbon shows capacity values and high stability at -20 and 60ºC. Our doping strategy proves to significantly increase the ionic and electronic conductivity of NVPF even at extreme conditions, delivering outstanding electrochemical performance and paving the way for advanced high-potential cathode materials.

Keywords: sodium-ion batteries, cathode materials, NASICON, Na3V2(PO4)2F3, Ion doping

Procedia PDF Downloads 37
16246 Temperature Evolution, Microstructure and Mechanical Properties of Heat-Treatable Aluminum Alloy Welded by Friction Stir Welding: Comparison with Tungsten Inert Gas

Authors: Saliha Gachi, Mouloud Aissani, Fouad Boubenider

Abstract:

Friction Stir Welding (FSW) is a solid-state welding technique that can join material without melting the plates to be welded. In this work, we are interested to demonstrate the potentiality of FSW for joining the heat-treatable aluminum alloy 2024-T3 which is reputed as difficult to be welded by fusion techniques. Thereafter, the FSW joint is compared with another one obtained from a conventional fusion process Tungsten Inert Gas (TIG). FSW welds are made up using an FSW tool mounted on a milling machine. Single pass welding was applied to fabricated TIG joint. The comparison between the two processes has been made on the temperature evolution, mechanical and microstructure behavior. The microstructural examination revealed that FSW weld is composed of four zones: Base metal (BM), Heat affected zone (HAZ), Thermo-mechanical affected zone (THAZ) and the nugget zone (NZ). The NZ exhibits a recrystallized equiaxed refined grains that induce better mechanical properties and good ductility compared to TIG joint where the grains have a larger size in the welded region compared with the BM due to the elevated heat input. The microhardness results show that, in FSW weld, the THAZ contains the lowest microhardness values and increase in the NZ; however, in TIG process, the lowest values are localized on the NZ.

Keywords: friction stir welding, tungsten inert gaz, aluminum, microstructure

Procedia PDF Downloads 260
16245 An Assessment of the Role of Actors in the Medical Waste Management Policy-Making Process of Bangladesh

Authors: Md Monirul Islam, Shahaduz Zaman, Mosarraf H. Sarker

Abstract:

Context: Medical waste management (MWM) is a critical sector in Bangladesh due to its impact on human health and the environment. There is a need to assess the current policies and identify the role of policy actors in the policy formulation and implementation process. Research Aim: The study aimed to evaluate the role of policy actors in the medical waste management policy-making process in Bangladesh, identify policy gaps, and provide actionable recommendations for improvement. Methodology: The study adopted a qualitative research method and conducted key informant interviews. The data collected were analyzed using the thematic coding approach through Atlas.ti software. Findings: The study found that policies are formulated at higher administrative levels and implemented in a top-down approach. Higher-level institutions predominantly contribute to policy development, while lower-level institutions focus on implementation. However, due to negligence, ignorance, and lack of coordination, medical waste management receives insufficient attention from the actors. The study recommends the need for immediate strategies, a comprehensive action plan, regular policy updates, and inter-ministerial meetings to enhance medical waste management practices and interventions. Theoretical Importance: The research contributes to evaluating the role of policy actors in medical waste management policymaking and implementation in Bangladesh. It identifies policy gaps and provides actionable recommendations for improvement. Data Collection: The study used key informant interviews as the data collection method. Thirty-six participants were interviewed, including influential policymakers and representatives of various administrative spheres. Analysis Procedures: The data collected was analyzed using the inductive thematic analysis approach. Question Addressed: The study aimed to assess the role of policy actors in medical waste management policymaking and implementation in Bangladesh. Conclusion: In conclusion, the study provides insights into the current medical waste management policy in Bangladesh, the role of policy actors in policy formulation and implementation, and the need for improved strategies and policy updates. The findings of this study can guide future policy-making efforts to enhance medical waste management practices and interventions in Bangladesh.

Keywords: key informant, medical waste management, policy maker, qualitative study

Procedia PDF Downloads 65
16244 Biogas Production from Pistachio (Pistacia vera L.) Processing Waste

Authors: İ. Çelik, Goksel Demirer

Abstract:

Turkey is the third largest producer of pistachio (Pistacia vera L.) after Iran and United States. Harvested pistachio nuts are covered with organic hull which is removed by de-hulling process. Most of the pistachio by-products which are produced during de-hulling process are considered as agricultural waste and often mixed with soil, to a lesser extent are used as feedstuff by local livestock farmers and a small portion is used as herbal medicine. Due to its high organic and phenolic content as well as high solids concentration, pistachio processing wastes create significant waste management problems unless they are properly managed. However, there is not a well-established waste management method compensating the waste generated during the processing of pistachios. This study investigated the anaerobic treatability and biogas generation potential of pistachio hull waste. The effect of pre-treatment on biogas generation potential was investigated. For this purpose, Biochemical Methane Potential (BMP) Assays were conducted for two Chemical Oxygen Demand (COD) concentrations of 22 and 33 g tCOD l-1 at the absence and presence of chemical and thermal pre-treatment methods. The results revealed anaerobic digestion of the pistachio de-hulling wastes and subsequent biogas production as a renewable energy source are possible. The observed percent COD removal and methane yield values of the pre-treated pistachio de-hulling waste samples were significantly higher than the raw pistachio de-hulling waste. The highest methane yield was observed as 213.4 ml CH4/g COD.

Keywords: pistachio de-hulling waste, biogas, renewable energy, pre-treatment

Procedia PDF Downloads 195
16243 Kinetic Modelling of Drying Process of Jumbo Squid (Dosidicus Gigas) Slices Subjected to an Osmotic Pretreatment under High Pressure

Authors: Mario Perez-Won, Roberto Lemus-Mondaca, Constanza Olivares-Rivera, Fernanda Marin-Monardez

Abstract:

This research presents the simultaneous application of high hydrostatic pressure (HHP) and osmotic dehydration (DO) as a pretreatment to hot –air drying of jumbo squid (Dosidicus gigas) cubes. The drying time was reduced to 2 hours at 60ºC and 5 hours at 40°C as compared to the jumbo squid samples untreated. This one was due to osmotic pressure under high-pressure treatment where increased salt saturation what caused an increasing water loss. Thus, a more reduced time during convective drying was reached, and so water effective diffusion in drying would play an important role in this research. Different working conditions such as pressure (350-550 MPa), pressure time (5-10 min), salt concentration, NaCl (10 y 15%) and drying temperature (40-60ºC) were optimized according to kinetic parameters of each mathematical model. The models used for drying experimental curves were those corresponding to Weibull, Page and Logarithmic models, however, the latest one was the best fitted to the experimental data. The values for water effective diffusivity varied from 4.82 to 6.59x10-9 m2/s for the 16 curves (DO+HHP) whereas the control samples obtained a value of 1.76 and 5.16×10-9 m2/s, for 40 and 60°C, respectively. On the other hand, quality characteristics such as color, texture, non-enzymatic browning, water holding capacity (WHC) and rehydration capacity (RC) were assessed. The L* (lightness) color parameter increased, however, b * (yellowish) and a* (reddish) parameters decreased for the DO+HHP treated samples, indicating treatment prevents sample browning. The texture parameters such as hardness and elasticity decreased, but chewiness increased with treatment, which resulted in a product with a higher tenderness and less firmness compared to the untreated sample. Finally, WHC and RC values of the most treatments increased owing to a minor damage in tissue cellular compared to untreated samples. Therefore, a knowledge regarding to the drying kinetic as well as quality characteristics of dried jumbo squid samples subjected to a pretreatment of osmotic dehydration under high hydrostatic pressure is extremely important to an industrial level so that the drying process can be successful at different pretreatment conditions and/or variable processes.

Keywords: diffusion coefficient, drying process, high pressure, jumbo squid, modelling, quality aspects

Procedia PDF Downloads 229