Search results for: plastic deformation capacity
4951 The Effect of Improvement Programs in the Mean Time to Repair and in the Mean Time between Failures on Overall Lead Time: A Simulation Using the System Dynamics-Factory Physics Model
Authors: Marcel Heimar Ribeiro Utiyama, Fernanda Caveiro Correia, Dario Henrique Alliprandini
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The importance of the correct allocation of improvement programs is of growing interest in recent years. Due to their limited resources, companies must ensure that their financial resources are directed to the correct workstations in order to be the most effective and survive facing the strong competition. However, to our best knowledge, the literature about allocation of improvement programs does not analyze in depth this problem when the flow shop process has two capacity constrained resources. This is a research gap which is deeply studied in this work. The purpose of this work is to identify the best strategy to allocate improvement programs in a flow shop with two capacity constrained resources. Data were collected from a flow shop process with seven workstations in an industrial control and automation company, which process 13.690 units on average per month. The data were used to conduct a simulation with the System Dynamics-Factory Physics model. The main variables considered, due to their importance on lead time reduction, were the mean time between failures and the mean time to repair. The lead time reduction was the output measure of the simulations. Ten different strategies were created: (i) focused time to repair improvement, (ii) focused time between failures improvement, (iii) distributed time to repair improvement, (iv) distributed time between failures improvement, (v) focused time to repair and time between failures improvement, (vi) distributed time to repair and between failures improvement, (vii) hybrid time to repair improvement, (viii) hybrid time between failures improvements, (ix) time to repair improvement strategy towards the two capacity constrained resources, (x) time between failures improvement strategy towards the two capacity constrained resources. The ten strategies tested are variations of the three main strategies for improvement programs named focused, distributed and hybrid. Several comparisons among the effect of the ten strategies in lead time reduction were performed. The results indicated that for the flow shop analyzed, the focused strategies delivered the best results. When it is not possible to perform a large investment on the capacity constrained resources, companies should use hybrid approaches. An important contribution to the academy is the hybrid approach, which proposes a new way to direct the efforts of improvements. In addition, the study in a flow shop with two strong capacity constrained resources (more than 95% of utilization) is an important contribution to the literature. Another important contribution is the problem of allocation with two CCRs and the possibility of having floating capacity constrained resources. The results provided the best improvement strategies considering the different strategies of allocation of improvement programs and different positions of the capacity constrained resources. Finally, it is possible to state that both strategies, hybrid time to repair improvement and hybrid time between failures improvement, delivered best results compared to the respective distributed strategies. The main limitations of this study are mainly regarding the flow shop analyzed. Future work can further investigate different flow shop configurations like a varying number of workstations, different number of products or even different positions of the two capacity constrained resources.Keywords: allocation of improvement programs, capacity constrained resource, hybrid strategy, lead time, mean time to repair, mean time between failures
Procedia PDF Downloads 1224950 Mechanical Testing on Bioplastics Obtained from Banana and Potato Peels in the City of Bogotá, Colombia
Authors: Juan Eduardo Rolon Rios, Fredy Alejandro Orjuela, Alexander Garcia Mariaca
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For banana and potato wastes, their peels are processed in order to make animal food with the condition that those wastes must not have started the decomposition process. One alternative to taking advantage of those wastes is to obtain a bioplastic based on starch from banana and potato shells. These products are 100% biodegradables, and researchers have been studying them for different applications, helping in the reduction of organic wastes and ordinary plastic wastes. Without petroleum affecting the prices of bioplastics, bioplastics market has a growing tendency and it is seen that it can keep this tendency in the medium term up to 350%. In this work, it will be shown the results for elasticity module and percent elongation for bioplastics obtained from a mixture of starch of bananas and potatoes peels, with glycerol as plasticizer. The experimental variables were the plasticizer percentage and the mixture between banana starch and potato starch. The results show that the bioplastics obtained can be used in different applications such as plastic bags or sorbets, verifying their admissible degradation percentages for each one of these applications. The results also show that they agree with the data found in the literature due to the fact that mixtures with a major amount of potato starch had the best mechanical properties because of the potato starch characteristics.Keywords: bioplastics, fruit waste, mechanical testing, mechanical properties
Procedia PDF Downloads 2934949 Textile Cottage Industry: A Facilitator for Capacity Building and Youth Empowerment
Authors: Salihu Maiwada
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The large scale textile industry in Nigeria was at one time the second largest employer of labor after government. With recent developments and changing situations, there is a serious decline in this sector which consequently forced the local textile industries to close down and the workers retrenched. the category of people worst hit was the youths and the middle age. This paper examines the potentials of the textile cottage industry as a facilitator for capacity building and economic empowerment among the Nigerian youths. The paper focuses on economic viability, persistence, and above-all, its potentials for poverty reduction as well as self employment. The methodology used in the study is the survey method and the instrument used to collect the necessary information is field interview. The results obtained showed that the textile cottage industries are flourishing and the Nigerian youths are engaged in the practice. In addition, the paper suggests areas that require government's financial intervention which will facilitate the establishment and ensure the sustainability of the textile cottage industry. The paper concludes with some recommendations for the youths and for the government.Keywords: capacity building, economic, empowerment, persistence, sustainability, youths
Procedia PDF Downloads 5874948 Inventory Management to Minimize Storage Costs and Improve Delivery Time in a Pharmaceutical Industry
Authors: Israel Becerril Rosales, Manuel González De La Rosa, Gerardo Villa Sánchez
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In this work, the effects that produce not having a good inventory management is analyzed, in addition of the way that how it affects the storage costs. The research began conducting the historical analysis about stored products, its storage capacity, and distribution. The results were not optimal, since in all its raw materials (RM) have overstocking, the warehouse capacity is only used by 61%, does not have a specific place for each of its RM, causing that the delivery times increases and makes difficult a cyclical inventory. These shortcomings allowed to view and select as design alternatives the inventory ABC, so that depending on the consumption of each RM would be redistributed by using economic amount requested. Also, the Delphi method to ensure the practical applicability of the proposed tool was used, taking in account comments and suggestions of the involved experts, as well as the compliance of NOM-059-SSA1-2015 good manufacturing practices of drug. With the actions implemented, the utilization rate drops of 61% to 32% capacity, it shows that the warehouse was not designed properly due to there is not an industrial engineering area.Keywords: lead time, improve delivery, storage costs, inventory management
Procedia PDF Downloads 2314947 Placement of Inflow Control Valve for Horizontal Oil Well
Authors: S. Thanabanjerdsin, F. Srisuriyachai, J. Chewaroungroj
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Drilling horizontal well is one of the most cost-effective method to exploit reservoir by increasing exposure area between well and formation. Together with horizontal well technology, intelligent completion is often co-utilized to increases petroleum production by monitoring/control downhole production. Combination of both technological results in an opportunity to lower water cresting phenomenon, a detrimental problem that does not lower only oil recovery but also cause environmental problem due to water disposal. Flow of reservoir fluid is a result from difference between reservoir and wellbore pressure. In horizontal well, reservoir fluid around the heel location enters wellbore at higher rate compared to the toe location. As a consequence, Oil-Water Contact (OWC) at the heel side of moves upward relatively faster compared to the toe side. This causes the well to encounter an early water encroachment problem. Installation of Inflow Control Valve (ICV) in particular sections of horizontal well can involve several parameters such as number of ICV, water cut constrain of each valve, length of each section. This study is mainly focused on optimization of ICV configuration to minimize water production and at the same time, to enhance oil production. A reservoir model consisting of high aspect ratio of oil bearing zone to underneath aquifer is drilled with horizontal well and completed with variation of ICV segments. Optimization of the horizontal well configuration is firstly performed by varying number of ICV, segment length, and individual preset water cut for each segment. Simulation results show that installing ICV can increase oil recovery factor up to 5% of Original Oil In Place (OOIP) and can reduce of produced water depending on ICV segment length as well as ICV parameters. For equally partitioned-ICV segment, more number of segment results in better oil recovery. However, number of segment exceeding 10 may not give a significant additional recovery. In first production period, deformation of OWC strongly depends on number of segment along the well. Higher number of segment results in smoother deformation of OWC. After water breakthrough at heel location segment, the second production period begins. Deformation of OWC is principally dominated by ICV parameters. In certain situations that OWC is unstable such as high production rate, high viscosity fluid above aquifer and strong aquifer, second production period may give wide enough window to ICV parameter to take the roll.Keywords: horizontal well, water cresting, inflow control valve, reservoir simulation
Procedia PDF Downloads 4184946 Numerical Analysis of Shallow Footing Rested on Geogrid Reinforced Sandy Soil
Authors: Seyed Abolhasan Naeini, Javad Shamsi Soosahab
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The use of geosynthetic reinforcement within the footing soils is a very effective and useful method to avoid the construction of costly deep foundations. This study investigated the use of geosynthetics for soil improvement based on numerical modeling using FELA software. Pressure settlement behavior and bearing capacity ratio of foundation on geogrid reinforced sand is investigated and the effect of different parameters like as number of geogrid layers and vertical distance between elements in three different relative density soil is studied. The effects of geometrical parameters of reinforcement layers were studied for determining the optimal values to reach to maximum bearing capacity. The results indicated that the optimum range of the distance ratio between the reinforcement layers was achieved at 0.5 to 0.6 and after number of geogrid layers of 4, no significant effect on increasing the bearing capacity of footing on reinforced sandy with geogridKeywords: geogrid, reinforced sand, FELA software, distance ratio, number of geogrid layers
Procedia PDF Downloads 1484945 Comparative Analysis of Biodegradation on Polythene and Plastics Buried in Fadama Soil Amended With Organic and Inorganic Fertilizer
Authors: Baba John, Abdullahi Mohammed
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The aim of this research is to compare the analysis of biodegradation on polythene and plastics buried in fadama soil amended with Organic and Inorganic fertilizer. Physico- chemical properties of the samples were determined. Bacteria and Fungi implicated in the biodegradation were identified and enumerated. Physico- chemical properties before the analysis indicated pH range of the samples from 4.28 – 5.80 , While the percentage Organic carbon and Organic matter was highest in cow dung samples with 3.89% and 6.69% respectively. The total Nitrogen percentage was recorded to be highest in Chicken dropping (0.68), while the availability of Phosphorus (P), Sodium (Na), Pottasium (K), and Magnessium (mg) was recorded to be highest in F – soil (Control), with values to be 37ppm, 1.63 Cmolkg-1, 0.35 Cmolkg-1 and 1.18 Cmolkg-1 respectively, except for calcium which was recorded to be highest in Cow dung (5.80 Cmolkg-1). However, physico – chemical properties of the samples after analysis indicated pH range of 4.6 – 5.80, Percentage Organic carbon and Organic matter was highest in Fadama soil mixed with fertilizer, having 0.7% and 1.2% respectively. Total Percentage Nitrogen content was found to be highest (0.56) in Fadama soil mixed with poultry dropping. Availability of Sodium (Na), Pottasium (K), and Calcium (Ca) was recorded to be highest in Fadama Soil mixed with Cow dung with values to be 0.64 Cmolkg-1, 2.07 Cmolkg-1 and 3.36 Cmolkg-1 respectively. The percentage weight loss of polythene and plastic bags after nine months in fadama soil mixed with poultry dropping was 11.9% for polythene and 6.0% for plastics. Weight loss in fadama soil mixed with cow dung was 18.1% for polythene and 4.7% for plastics. Weight loss of polythene and plastic in fadama soil mixed with fertilizer (NPK) was 7.4% for polythene and 3.3% for plastics. While, the percentage weight loss of polythene and plastics after nine months of burial in fadama soil (control) was 3.5% and 0.0% respectively. The bacteria species isolated from Fadama soil, organic and inorganic fertilizers before amendments include: S. aureus, Micrococcus sp, Streptococcus. pyogenes, Psuedomonas aeruginosa Bacillus subtilis and Bacillus cereus. The fungi species include: Aspergillus niger, Aspergillus fumigatus, Aspergillus flavus, Fusarium sp, Mucor sp Penicillium sp and Candida sp. The bacteria species isolated and characterized after nine months of seeding include: S. aureus, Micrococcus sp, S. pyogenes, P. aeruginosa and B. subtilis. The fungi species are: A. niger A. flavus, A. fumigatus, Mucor sp, Penicillium sp and Fusarium sp. The result of this study indicated that plastic materials can be degraded in the fadama soil irrespective of whether the soil is amended or not. The Period of composting also has a significant impact on the rate at which polythene and plastics are degraded.Keywords: Fadama, fertilizer, plastic and polythene, biodegradation
Procedia PDF Downloads 5434944 An Anode Based on Modified Silicon Nanostructured for Lithium – Ion Battery Application
Authors: C. Yaddaden, M. Berouaken, L. Talbi, K. Ayouz, M. Ayat, A. Cheriet, F. Boudeffar, A. Manseri, N. Gabouze
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Lithium-ion batteries (LIBs) are widely used in various electronic devices due to their high energy density. However, the performance of the anode material in LIBs is crucial for enhancing the battery's overall efficiency. This research focuses on developing a new anode material by modifying silicon nanostructures, specifically porous silicon nanowires (PSiNWs) and porous silicon nanoparticles (NPSiP), with silver nanoparticles (Ag) to improve the performance of LIBs. The aim of this research is to investigate the potential application of PSiNWs/Ag and NPSiP/Ag as anodes in LIBs and evaluate their performance in terms of specific capacity and Coulombic efficiency. The research methodology involves the preparation of PSiNWs and NPSiP using metal-assisted chemical etching and electrochemical etching techniques, respectively. The Ag nanoparticles are introduced onto the nanostructures through electrodissolution of the porous film and ultrasonic treatment. Galvanostatic charge/discharge measurements are conducted between 1 and 0.01 V to evaluate the specific capacity and Coulombic efficiency of both PSiNWs/Ag and NPSiP/Ag electrodes. The specific capacity of the PSiNWs/Ag electrode is approximately 1800 mA h g-1, with a Coulombic efficiency of 98.8% at the first charge/discharge cycle. On the other hand, the NPSiP/Ag electrode exhibits a specific capacity of 2600 mAh g-1. Both electrodes show a slight increase in capacity retention after 80 cycles, attributed to the high porosity and surface area of the nanostructures and the stabilization of the solid electrolyte interphase (SEI). This research highlights the potential of using modified silicon nanostructures as anodes for LIBs, which can pave the way for the development of more efficient lithium-ion batteries.Keywords: porous silicon nanowires, silicon nanoparticles, lithium-ion batteries, galvanostatic charge/discharge
Procedia PDF Downloads 634943 Sensitivity Analysis of the Thermal Properties in Early Age Modeling of Mass Concrete
Authors: Farzad Danaei, Yilmaz Akkaya
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In many civil engineering applications, especially in the construction of large concrete structures, the early age behavior of concrete has shown to be a crucial problem. The uneven rise in temperature within the concrete in these constructions is the fundamental issue for quality control. Therefore, developing accurate and fast temperature prediction models is essential. The thermal properties of concrete fluctuate over time as it hardens, but taking into account all of these fluctuations makes numerical models more complex. Experimental measurement of the thermal properties at the laboratory conditions also can not accurately predict the variance of these properties at site conditions. Therefore, specific heat capacity and the heat conductivity coefficient are two variables that are considered constant values in many of the models previously recommended. The proposed equations demonstrate that these two quantities are linearly decreasing as cement hydrates, and their value are related to the degree of hydration. The effects of changing the thermal conductivity and specific heat capacity values on the maximum temperature and the time it takes for concrete to reach that temperature are examined in this study using numerical sensibility analysis, and the results are compared to models that take a fixed value for these two thermal properties. The current study is conducted in 7 different mix designs of concrete with varying amounts of supplementary cementitious materials (fly ash and ground granulated blast furnace slag). It is concluded that the maximum temperature will not change as a result of the constant conductivity coefficient, but variable specific heat capacity must be taken into account, also about duration when a concrete's central node reaches its max value again variable specific heat capacity can have a considerable effect on the final result. Also, the usage of GGBFS has more influence compared to fly ash.Keywords: early-age concrete, mass concrete, specific heat capacity, thermal conductivity coefficient
Procedia PDF Downloads 774942 Gender Differences in Walking Capacity and Cardiovascular Regulation in Patients with Peripheral Arterial Disease
Authors: Gabriel Cucato, Marilia Correia, Wagner Domingues, Aline Palmeira, Paulo Longano, Nelson Wolosker, Raphael Ritti-Dias
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Women with peripheral arterial disease (PAD) present lower walking capacity in comparison with men. However, whether cardiovascular regulation is also different between genders is unknown. Thus, the aim of this study was to compare walking capacity and cardiovascular regulation between men and women with PAD. A total of 23 women (66±7 yrs) and 31 men (64±9 yrs) were recruited. Patients performed a 6-minute test and the onset claudication distance and total walking distance were measured. Additionally, cardiovascular regulation was assessed by arterial stiffness (pulse wave velocity and augmentation index) and heart rate variability (frequency domain). Independent T test or Mann-Whitney U test were performed. In comparison with men, women present lower onset claudication distance (108±66m vs. 143±50m; P=0.032) and total walking distance (286±83m vs. 361±91 m, P=0.007). Regarding cardiovascular regulation, there were no differences in heart rate variability SDNN (72±160ms vs. 32±22ms, P=0.587); RMSSD (75±209 vs. 25±22ms, P=0.726); pNN50 (11±17ms vs. 8±14ms, P=0.836) in women and men, respectively. Moreover, there were no difference in augmentation index (39±10% vs. 34±11%, P=0.103); pulse pressure (59±17mmHg vs. 56±19mmHg, P=0.593) and pulse wave velocity (8.6±2.6m\s vs. 9.0±2.7m/s, P=0.580). In conclusion, women have impaired walking capacity compared to men. However, sex differences were not observed on cardiovascular regulation in patients with PAD.Keywords: exercise, intermittent claudication, cardiovascular load, arterial stiffness
Procedia PDF Downloads 3924941 Numerical Simulations on the Torsional Behavior of Multistory Concrete Masonry Buildings
Authors: Alvaro Jose Cordova, Hsuan Teh Hu
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The use of concrete masonry constructions in developing countries has become very frequent, especially for domestic purpose. Most of them with asymmetric wall configurations in plan resulting in significant torsional actions when subjected to seismic loads. The study consisted on the finding of a material model for hollow unreinforced concrete masonry and a validation with experimental data found in literature. Numerical simulations were performed to 20 buildings with variations in wall distributions and heights. Results were analyzed by inspection and with a non-linear static method. The findings revealed that eccentricities as well as structure rigidities have a strong influence on the overall response of concrete masonry buildings. In addition, slab rotations depicted more accurate information about the torsional behavior than maximum versus average displacement ratios. The failure modes in low buildings were characterized by high tensile strains in the first floor. Whereas in tall buildings these strains were lowered significantly by higher compression stresses due to a higher self-weight. These tall buildings developed multiple plastic hinges along the height. Finally, the non-linear static analysis exposed a brittle response for all masonry assemblies. This type of behavior is undesired in any construction and the need for a material model for reinforced masonry is pointed out.Keywords: concrete damaged plasticity, concrete masonry, macro-modeling, nonlinear static analysis, torsional capacity
Procedia PDF Downloads 2944940 Effect of Fresh Concrete Curing Methods on Its Compressive Strength
Authors: Xianghe Dai, Dennis Lam, Therese Sheehan, Naveed Rehman, Jie Yang
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Concrete is one of the most used construction materials that may be made onsite as fresh concrete and then placed in formwork to produce the desired shapes of structures. It has been recognized that the raw materials and mix proportion of concrete dominate the mechanical characteristics of hardened concrete, and the curing method and environment applied to the concrete in early stages of hardening will significantly influence the concrete properties, such as compressive strength, durability, permeability etc. In construction practice, there are various curing methods to maintain the presence of mixing water throughout the early stages of concrete hardening. They are also beneficial to concrete in hot weather conditions as they provide cooling and prevent the evaporation of water. Such methods include ponding or immersion, spraying or fogging, saturated wet covering etc. Also there are various curing methods that may be implemented to decrease the level of water lost which belongs to the concrete surface, such as putting a layer of impervious paper, plastic sheeting or membrane on the concrete to cover it. In the concrete material laboratory, accelerated strength gain methods supply the concrete with heat and additional moisture by applying live steam, coils that are subject to heating or pads that have been warmed electrically. Currently when determining the mechanical parameters of a concrete, the concrete is usually sampled from fresh concrete on site and then cured and tested in laboratories where standardized curing procedures are adopted. However, in engineering practice, curing procedures in the construction sites after the placing of concrete might be very different from the laboratory criteria, and this includes some standard curing procedures adopted in the laboratory that can’t be applied on site. Sometimes the contractor compromises the curing methods in order to reduce construction costs etc. Obviously the difference between curing procedures adopted in the laboratory and those used on construction sites might over- or under-estimate the real concrete quality. This paper presents the effect of three typical curing methods (air curing, water immersion curing, plastic film curing) and of maintaining concrete in steel moulds on the compressive strength development of normal concrete. In this study, Portland cement with 30% fly ash was used and different curing periods, 7 days, 28 days and 60 days were applied. It was found that the highest compressive strength was observed from concrete samples to which 7-day water immersion curing was applied and from samples maintained in steel moulds up to the testing date. The research results implied that concrete used as infill in steel tubular members might develop a higher strength than predicted by design assumptions based on air curing methods. Wrapping concrete with plastic film as a curing method might delay the concrete strength development in the early stages. Water immersion curing for 7 days might significantly increase the concrete compressive strength.Keywords: compressive strength, air curing, water immersion curing, plastic film curing, maintaining in steel mould, comparison
Procedia PDF Downloads 2934939 Characterization and Nanostructure Formation of Banana Peels Nanosorbent with Its Application
Authors: Opeyemi Atiba-Oyewo, Maurice S. Onyango, Christian Wolkersdorfer
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Characterization and nanostructure formation of banana peels as sorbent material are described in this paper. The transformation of this agricultural waste via mechanical milling to enhance its properties such as changed in microstructure and surface area for water pollution control and other applications were studied. Mechanical milling was employed using planetary continuous milling machine with ethanol as a milling solvent and the samples were taken at time intervals between 10 h to 30 h to examine the structural changes. The samples were characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infra-red (FTIR), Transmission electron microscopy (TEM) and Brunauer Emmett and teller (BET). Results revealed three typical structures with different deformation mechanisms and the grain-sizes within the range of (71-12 nm), nanostructure of the particles and fibres. The particle size decreased from 65µm to 15 nm as the milling progressed for a period of 30 h. The morphological properties of the materials indicated that the particle shapes becomes regular and uniform as the milling progresses. Furthermore, particles fracturing resulted in surface area increment from 1.0694-4.5547 m2/g. The functional groups responsible for the banana peels capacity to coordinate and remove metal ions, such as the carboxylic and amine groups were identified at absorption bands of 1730 and 889 cm-1, respectively. However, the choice of this sorbent material for the sorption or any application will depend on the composition of the pollutant to be eradicated.Keywords: characterization, nanostructure, nanosorbent, eco-friendly, banana peels, mechanical milling, water quality
Procedia PDF Downloads 2844938 Screening Deformed Red Blood Cells Irradiated by Ionizing Radiations Using Windowed Fourier Transform
Authors: Dahi Ghareab Abdelsalam Ibrahim, R. H. Bakr
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Ionizing radiation, such as gamma radiation and X-rays, has many applications in medical diagnoses and cancer treatment. In this paper, we used the windowed Fourier transform to extract the complex image of the deformed red blood cells. The real values of the complex image are used to extract the best fitting of the deformed cell boundary. Male albino rats are irradiated by γ-rays from ⁶⁰Co. The male albino rats are anesthetized with ether, and then blood samples are collected from the eye vein by heparinized capillary tubes for studying the radiation-damaging effect in-vivo by the proposed windowed Fourier transform. The peripheral blood films are prepared according to the Brown method. The peripheral blood film is photographed by using an Automatic Image Contour Analysis system (SAMICA) from ELBEK-Bildanalyse GmbH, Siegen, Germany. The SAMICA system is provided with an electronic camera connected to a computer through a built-in interface card, and the image can be magnified up to 1200 times and displayed by the computer. The images of the peripheral blood films are then analyzed by the windowed Fourier transform method to extract the precise deformation from the best fitting. Based on accurate deformation evaluation of the red blood cells, diseases can be diagnosed in their primary stages.Keywords: windowed Fourier transform, red blood cells, phase wrapping, Image processing
Procedia PDF Downloads 854937 Characterization of a LiFeOP₄ Battery Cell with Mechanical Responses
Authors: Ki-Yong Oh, Eunji Kwak, Due Su Son, Siheon Jung
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A pouch type of 10 Ah LiFePO₄ battery cell is characterized with two mechanical responses: swelling and bulk force. Both responses vary upon the state of charge significantly, whereas voltage shows flat responses, suggesting that mechanical responses can become a sensitive gauge to characterize microstructure transformation of a battery cell. The derivative of swelling s with respect to capacity Q, (ds/dQ) and the derivative of force F with respect to capacity Q, (dF/dQ) more clearly identify phase transitions of cathode and anode electrodes in the overall charge process than the derivative of voltage V with respect to capacity Q, (dV/dQ). Especially, the force versus swelling curves over the state of charge clearly elucidates three different stiffness over the state of charge oriented from phase transitions: the α-phase, the β-phase, and the metastable solid-solution phase. The observation from mechanical responses suggests that macro-scale mechanical responses of a battery cell are directly correlated to microscopic transformation of a battery cell.Keywords: force response, LiFePO₄ battery, strain response, stress response, swelling response
Procedia PDF Downloads 1704936 State Capacity and the Adoption of Restrictive Asylum Policies in Developing Countries
Authors: Duncan K. Espenshade
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Scholars have established expectations regarding how the political and economic interests of a country's people and elites can influence its migration policies. Most of the scholarship exploring the adoption of migration policies focuses on the developed world, focusing on the cultural, political, and economic influences that drive restrictive policies in developed countries. However, despite the scholarly focus on migration policies in developed countries, most internationally displaced people reside in developing countries. Furthermore, while the political and economic factors that influence migration policy in developed countries are likely at play in developing states, developing states also face unique hurdles to policy formation not present in developed states. Namely, this article explores how state capacity, or in this context, a state's de facto ability to restrict or absorb migration inflows, influences the adoption of migration policies in developing countries. Using Cox-Proportional hazard models and recently introduced data on asylum policies in developing countries, this research finds that having a greater ability to restrict migration flows is associated with a reduced likelihood of adopting liberal asylum policies. Future extensions of this project will explore the adoption of asylum policies as a two-stage process, in which the available decision set of political actors is first constrained by a state's restrictive and absorptive capacity in the first stage, with the political, economic, and cultural factors influencing the policy adopted in the second stage.Keywords: state capacity, international relations, foreign policy, migration
Procedia PDF Downloads 1064935 Reducing Greenhouse Gass Emissions by Recyclable Material Bank Project of Universities in Central Region of Thailand
Authors: Ronbanchob Apiratikul
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This research studied recycled waste by the Recyclable Material Bank Project of 4 universities in the central region of Thailand for the evaluation of reducing greenhouse gas emissions compared with landfilling activity during July 2012 to June 2013. The results showed that the projects collected total amount of recyclable wastes of about 911,984.80 kilograms. Office paper had the largest amount among these recycled wastes (50.68% of total recycled waste). Groups of recycled waste can be prioritized from high to low according to their amount as paper, plastic, glass, mixed recyclables, and metal, respectively. The project reduced greenhouse gas emissions equivalent to about 2814.969 metric tons of carbon dioxide. The most significant recycled waste that affects the reduction of greenhouse gas emissions is office paper which is 70.16% of total reduced greenhouse gasses emission. According to amount of reduced greenhouse gasses emission, groups of recycled waste can be prioritized from high to low significances as paper, plastic, metals, mixed recyclables, and glass, respectively.Keywords: recycling, garbage bank, waste management, recyclable wastes, greenhouse gases
Procedia PDF Downloads 4254934 Enzymatic Degradation of Poly (Butylene Adipate Terephthalate) Copolymer Using Lipase B From Candida Antarctica and Effect of Poly (Butylene Adipate Terephthalate) on Plant Growth
Authors: Aqsa Kanwal, Min Zhang, Faisal Sharaf, Li Chengtao
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The globe is facing increasing challenges of plastic pollution due to single-use of plastic-based packaging material. The plastic material is continuously being dumped into the natural environment, which causes serious harm to the entire ecosystem. Polymer degradation in nature is very difficult, so the use of biodegradable polymers instead of conventional polymers can mitigate this issue. Due to the good mechanical properties and biodegradability, aliphatic-aromatic polymers are being widely commercialized. Due to the advancement in molecular biology, many studies have reported specific microbes that can effectively degrade PBAT. Aliphatic polyesters undergo hydrolytic cleavage of ester groups, so they can be easily degraded by microorganisms. In this study, we investigated the enzymatic degradation of poly (butylene adipate terephthalate) (PBAT) copolymer using lipase B from Candida Antarctica (CALB). Results of the study displayed approximately 5.16 % loss in PBAT mass after 2 days which significantly increased to approximately 15.7 % at the end of the experiment (12 days) as compared to blank. The pH of the degradation solution also displayed significant reduction and reached the minimum value of 6.85 at the end of the experiment. The structure and morphology of PBAT after degradation were characterized by FTIR, XRD, SEM, and TGA. FTIR analysis showed that after degradation many peaks become weaker and the peak at 2950 cm-1 almost disappeared after 12 days. The XRD results indicated that as the degradation time increases the intensity of diffraction peaks slightly increases as compared to the blank PBAT. TGA analysis also confirmed the successful degradation of PBAT with time. SEM micrographs further confirmed that degradation has occurred. Hence, biodegradable polymers can widely be used. The effect of PBAT biodegradation on plant growth was also studied and it was found that PBAT has no toxic effect on the growth of plants. Hence PBAT can be employed in a wide range of applications.Keywords: aliphatic-aromatic co-polyesters, polybutylene adipate terephthalate, lipase (CALB), biodegradation, plant growth
Procedia PDF Downloads 794933 Structural Equation Modeling Semiparametric in Modeling the Accuracy of Payment Time for Customers of Credit Bank in Indonesia
Authors: Adji Achmad Rinaldo Fernandes
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The research was conducted to apply semiparametric SEM modeling to the timeliness of paying credit. Semiparametric SEM is structural modeling in which two combined approaches of parametric and nonparametric approaches are used. The analysis method in this research is semiparametric SEM with a nonparametric approach using a truncated spline. The data in the study were obtained through questionnaires distributed to Bank X mortgage debtors and are confidential. The study used 3 variables consisting of one exogenous variable, one intervening endogenous variable, and one endogenous variable. The results showed that (1) the effect of capacity and willingness to pay variables on timeliness of payment is significant, (2) modeling the capacity variable on willingness to pay also produces a significant estimate, (3) the effect of the capacity variable on the timeliness of payment variable is not influenced by the willingness to pay variable as an intervening variable, (4) the R^2 value of 0.763 or 76.33% indicates that the model has good predictive relevance.Keywords: structural equation modeling semiparametric, credit bank, accuracy of payment time, willingness to pay
Procedia PDF Downloads 444932 Modeling Water Resources Carrying Capacity, Optimizing Water Treatment, Smart Water Management, and Conceptualizing a Watershed Management Approach
Authors: Pius Babuna
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Sustainable water use is important for the existence of the human race. Water resources carrying capacity (WRCC) measures the sustainability of water use; however, the calculation and optimization of WRCC remain challenging. This study used a mathematical model (the Logistics Growth of Water Resources -LGWR) and a linear objective function to model water sustainability. We tested the validity of the models using data from Ghana. Total freshwater resources, water withdrawal, and population data were used in MATLAB. The results show that the WRCC remains sustainable until the year 2132 ±18, when half of the total annual water resources will be used. The optimized water treatment cost suggests that Ghana currently wastes GHȼ 1115.782± 50 cedis (~$182.21± 50) per water treatment plant per month or ~ 0.67 million gallons of water in an avoidable loss. Adopting an optimized water treatment scheme and a watershed management approach will help sustain the WRCC.Keywords: water resources carrying capacity, smart water management, optimization, sustainable water use, water withdrawal
Procedia PDF Downloads 874931 Comparative Syudy Of Heat Transfer Capacity Limits of Heat Pipe
Authors: H. Shokouhmand, A. Ghanami
Abstract:
Heat pipe is simple heat transfer device which combines the conduction and phase change phenomena to control the heat transfer without any need for external power source. At hot surface of heat pipe, the liquid phase absorbs heat and changes to vapor phase. The vapor phase flows to condenser region and with the loss of heat changes to liquid phase. Due to gravitational force the liquid phase flows to evaporator section.In HVAC systems the working fluid is chosen based on the operating temperature. The heat pipe has significant capability to reduce the humidity in HVAC systems. Each HVAC system which uses heater, humidifier or dryer is a suitable nominate for the utilization of heat pipes. Generally heat pipes have three main sections: condenser, adiabatic region and evaporator.Performance investigation and optimization of heat pipes operation in order to increase their efficiency is crucial. In present article, a parametric study is performed to improve the heat pipe performance. Therefore, the heat capacity of heat pipe with respect to geometrical and confining parameters is investigated. For the better observation of heat pipe operation in HVAC systems, a CFD simulation in Eulerian- Eulerian multiphase approach is also performed. The results show that heat pipe heat transfer capacity is higher for water as working fluid with the operating temperature of 340 K. It is also observed that the vertical orientation of heat pipe enhances it’s heat transfer capacity.Keywords: heat pipe, HVAC system, grooved heat pipe, heat pipe limits
Procedia PDF Downloads 3764930 Evaluation of the Effectiveness of Barriers for the Control of Rats in Rice Plantation Field
Authors: Melina, Jumardi Jumardi, Erwin Erwin, Sri Nuraminah, Andi Nasruddin
Abstract:
The rice field rat (Rattus argentiventer Robinson and Kloss) is a pest causing the greatest yield loss of rice plants, especially in lowland agroecosystems with intensive cropping patterns (2-3 plantings per year). Field mice damage rice plants at all stages of growth, from seedling to harvest, even in storage warehouses. Severe damage with yield loss of up to 100% occurs if rats attack rice at the generative stage because the plants are no longer able to recover by forming new tillers. Farmers mainly use rodenticides in the form of poisoned baits or as fumigants, which are applied to rat burrow holes. This practice is generally less effective because mice are able to avoid the poison or become resistant after several exposures to it. In addition, excessive use of rodenticides can have negative impacts on the environment and non-target organisms. For this reason, this research was conducted to evaluate the effectiveness of fences as an environmentally friendly mechanical control method in reducing rice yield losses due to rat attacks. This study used a factorial randomized block design. The first factor was the fence material, namely galvanized zinc plate and plastic. The second factor was the height of the fence, namely 25, 50, 75, and 100 cm from the ground level. Each treatment combination was repeated five times. Data shows that zinc fences with a height of 75 and 100 cm are able to provide full protection to plants from rat infestations throughout the planting season. However, zinc fences with a height of 25 and 50 cm failed to prevent rat attacks. Plastic fences with a height of 25 and 50 cm failed to prevent rat attacks during the planting season, whereas 75 and 100 cm were able to prevent rat attacks until all the crops outside of the fence had been eaten by rats. The rat managed to get into the fence by biting the plastic fence close to the ground. Thus, the research results show that fences made of zinc plate with a height of at least 75 cm from the ground surface are effective in preventing plant damage caused by rats. To our knowledge, this research is the first to quantify the effectiveness of fences as a control of field rodents.Keywords: rice field rat, Rattus argentiventer, fence, rice
Procedia PDF Downloads 394929 Fluvial Stage-Discharge Rating of a Selected Reach of Jamuna River
Authors: Makduma Zahan Badhan, M. Abdul Matin
Abstract:
A study has been undertaken to develop a fluvial stage-discharge rating curve for Jamuna River. Past Cross-sectional survey of Jamuna River reach within Sirajgonj and Tangail has been analyzed. The analysis includes the estimation of discharge carrying capacity, possible maximum scour depth and sediment transport capacity of the selected reaches. To predict the discharge and sediment carrying capacity, stream flow data which include cross-sectional area, top width, water surface slope and median diameter of the bed material of selected stations have been collected and some are calculated from reduced level data. A well-known resistance equation has been adopted and modified to a simple form in order to be used in the present analysis. The modified resistance equation has been used to calculate the mean velocity through the channel sections. In addition, a sediment transport equation has been applied for the prediction of transport capacity of the various sections. Results show that the existing drainage sections of Jamuna channel reach under study have adequate carrying capacity under existing bank-full conditions, but these reaches are subject to bed erosion even in low flow situations. Regarding sediment transport rate, it can be estimated that the channel flow has a relatively high range of bed material concentration. Finally, stage discharge curves for various sections have been developed. Based on stage-discharge rating data of various sections, water surface profile and sediment-rating curve of Jamuna River have been developed and also the flooding conditions have been analyzed from predicted water surface profile.Keywords: discharge rating, flow profile, fluvial, sediment rating
Procedia PDF Downloads 1854928 Experimental Investigation on Cold-Formed Steel Foamed Concrete Composite Wall under Compression
Authors: Zhifeng Xu, Zhongfan Chen
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A series of tests on cold-formed steel foamed concrete (CSFC) composite walls subjected to axial load were proposed. The primary purpose of the experiments was to study the mechanical behavior and identify the failure modes of CSFC composite walls. Two main factors were considered in this study: 1) specimen with pouring foamed concrete or without and 2) different foamed concrete density ranks (corresponding to different foamed concrete strength). The interior space between two pieces of straw board of the specimen W-2 and W-3 were poured foamed concrete, and the specimen W-1 does not have foamed concrete core. The foamed concrete density rank of the specimen W-2 was A05 grade, and that of the specimen W-3 was A07 grade. Results showed that the failure mode of CSFC composite wall without foamed concrete was distortional buckling of cold-formed steel (CFS) column, and that poured foamed concrete includes the local crushing of foamed concrete and local buckling of CFS column, but the former prior to the later. Compared with CSFC composite wall without foamed concrete, the ultimate bearing capacity of spec imens poured A05 grade and A07 grade foamed concrete increased 1.6 times and 2.2 times respectively, and specimen poured foamed concrete had a low vertical deformation. According to these results, the simplified calculation formula for the CSFC wall subjected to axial load was proposed, and the calculated results from this formula are in very good agreement with the test results.Keywords: cold-formed steel, composite wall, foamed concrete, axial behavior test
Procedia PDF Downloads 3374927 Golden Brain Theory (GBT) for Language Learning
Authors: Tapas Karmaker
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Centuries ago, we came to know about ‘Golden Ratio’ also known as Golden Angle. The idea of this research is based on this theme. Researcher perceives ‘The Golden Ratio’ in terms of harmony, meaning that every single item in the universe follows a harmonic behavior. In case of human being, brain responses easily and quickly to this harmony to help memorization. In this theory, harmony means a link. This study has been carried out on a segment of school students and a segment of common people for a period of three years from 2003 to 2006. The research in this respect intended to determine the impact of harmony in the brain of these people. It has been found that students and common people can increase their memorization capacity as much as 70 times more by applying this method. This method works faster and better between age of 8 and 30 years. This result was achieved through tests to assess memorizing capacity by using tools like words, rhymes, texts, math and drawings. The research concludes that this harmonic method can be applied for improving the capacity of learning languages, for the better quality of lifestyle, or any other terms of life as well as in professional activity.Keywords: language, education, golden brain, learning, teaching
Procedia PDF Downloads 2004926 Varieties of State Role: Through the Case of East Asia's Broadband Policy
Authors: Heesu Kim
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This paper determines the varieties of state roles played in East Asia’s telecommunication market, regarding broadband industry. Technological capacity and the relationship between state and market affect the varieties of state role. In explaining the state’s engagement in the market, technology has always been considered as a necessary and sufficient condition. However technology variable has been useful in only explaining the extent of state’s involvement. This paper contributes by bringing in the political-economic factor, which is the relationship between state and market. This factor aids in distinguishing the varieties of state role played in emerging industries. Interaction between these two variables distinguishes 4 types of state roles played in the broadband industry. These roles are distinguished and characterized by the intensity of state’s intervention and the existence of technological capacity. This paper classifies four types of state role through the case of Singapore, China, Taiwan and Korea’s broadband industrial policy.Keywords: East Asia, entrpreneurial state, industrial policy, regulatory state, technological capacity
Procedia PDF Downloads 1724925 Out-of-Plane Free Vibration of Functionally Graded Circular Curved Beams with Temperature Dependent Material Properties in Thermal Environment
Authors: M. M. Atashi, P. Malekzadeh
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A first known formulation for the out-of-plane free vibration analysis of functionally graded (FG) circular curved beams in thermal environment and with temperature dependent material properties is presented. The formulation is based on the first order shear deformation theory (FSDT), which includes the effects of shear deformation and rotary inertia due to both torsional and flexural vibrations. The material properties are assumed to be temperature dependent and graded in the direction normal to the plane of the beam curvature. The equations of motion and the related boundary conditions, which include the effects of initial thermal stresses, are derived using the Hamilton’s principle. Differential quadrature method (DQM), as an efficient and accurate numerical method, is adopted to solve the thermoelastic equilibrium equations and the equations of motion. The fast rate of convergence of the method is investigated and the formulations are validated by comparing the results in the limit cases with the available solutions in the literature for isotropic circular curved beams. In addition, for FG circular curved beams with soft simply supported edges, the results are compared with the obtained exact solutions. Then, the effects of temperature rise, boundary conditions, material and geometrical parameters on the natural frequencies are investigated.Keywords: out of plane, free vibration, curved beams, functionally graded, thermal environment
Procedia PDF Downloads 3564924 Collaborative Technology Implementation Success and Knowledge Capacity: Case of Tunisian Banks with Mixed Capital
Authors: Amira Khelil, Habib Affes
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Organization resource planning implementation success is important. Today`s competitors in business, in enterprise resource planning and in managing are becoming one of the main tools of achieving competitiveness in business. Resource technologies are considered as an infrastructure to create and maintain business to improve front and back-office efficiency and effectiveness. This study is significant to bring new ideas in determining the key antecedents which are technological resource planning implementation based on knowledge capacity perspectives and help to understand the key success factor in the Tunisian banks. Based on a survey of 150 front office Tunisian agents working in Tunisian banks with mixed capital, using Groupware system, only 51 respondents had given feedback to this survey. By using Warp PLS 3.0, through several tests the relationship between knowledge capability and Groupware implementation success having beta coefficient 0.37 and P-Value <0.01. This result highlights that knowledge capability of bank agent can influence the success of the Groupware implementation.Keywords: groupware implementation, knowledge capacity, partial least squares method, Tunisian banks
Procedia PDF Downloads 4894923 FEM Simulation of Tool Wear and Edge Radius Effects on Residual Stress in High Speed Machining of Inconel718
Authors: Yang Liu, Mathias Agmell, Aylin Ahadi, Jan-Eric Stahl, Jinming Zhou
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Tool wear and tool geometry have significant effects on the residual stresses in the component produced by high-speed machining. In this paper, Coupled Eulerian and Lagrangian (CEL) model is adopted to investigate the residual stress in high-speed machining of Inconel718 with a CBN170 cutting tool. The result shows that the mesh with the smallest size of 5 um yields cutting forces and chip morphology in close agreement with the experimental data. The analysis of thermal loading and mechanical loading are performed to study the effect of segmented chip morphology on the machined surface topography and residual stress distribution. The effects of cutting edge radius and flank wear on residual stresses formation and distribution on the workpiece were also investigated. It is found that the temperature within 100um depth of the machined surface increases drastically due to the more friction heat generation with the contact area of tool and workpiece increasing when a larger edge radius and flank wear are used. With the depth further increasing, the temperature drops rapidly for all cases due to the low conductivity of Inconel718. Consequently, higher and deeper tensile residual stress is generated on the superficial. Furthermore, an increased depth of plastic deformation and compressive residual stress is noticed in the subsurface, which is attributed to the reduction of the yield strength under the thermal effect. Besides, the ploughing effect produced by a larger tool edge radius contributes more than flank wear. The magnitude variation of the compressive residual stress caused by various edge radius and flank wear have a totally opposite trend, which depends on the magnitude of the ploughing and friction pressure acting on the machined surface.Keywords: Coupled Eulerian Lagrangian, segmented chip, residual stress, tool wear, edge radius, Inconel718
Procedia PDF Downloads 1464922 Comparative Study of Heat Transfer Capacity Limits of Heat Pipes
Authors: H. Shokouhmand, A. Ghanami
Abstract:
Heat pipe is simple heat transfer device which combines the conduction and phase change phenomena to control the heat transfer without any need for external power source. At hot surface of heat pipe, the liquid phase absorbs heat and changes to vapor phase. The vapor phase flows to condenser region and with the loss of heat changes to liquid phase. Due to gravitational force the liquid phase flows to evaporator section.In HVAC systems the working fluid is chosen based on the operating temperature. The heat pipe has significant capability to reduce the humidity in HVAC systems. Each HVAC system which uses heater, humidifier or dryer is a suitable nominate for the utilization of heat pipes. Generally heat pipes have three main sections: condenser, adiabatic region and evaporator.Performance investigation and optimization of heat pipes operation in order to increase their efficiency is crucial. In present article, a parametric study is performed to improve the heat pipe performance. Therefore, the heat capacity of heat pipe with respect to geometrical and confining parameters is investigated. For the better observation of heat pipe operation in HVAC systems, a CFD simulation in Eulerian- Eulerian multiphase approach is also performed. The results show that heat pipe heat transfer capacity is higher for water as working fluid with the operating temperature of 340 K. It is also showed that the vertical orientation of heat pipe enhances it’s heat transfer capacity.Keywords: heat pipe, HVAC system, grooved Heat pipe, heat pipe limits
Procedia PDF Downloads 421