Search results for: silicone rubber insulators
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 367

Search results for: silicone rubber insulators

187 Soft Robotic System for Mechanical Stimulation of Scaffolds During Dynamic Cell Culture

Authors: Johanna Perdomo, Riki Lamont, Edmund Pickering, Naomi C. Paxton, Maria A. Woodruff

Abstract:

Background: Tissue Engineering (TE) has combined advanced materials, such as biomaterials, to create affordable scaffolds and dynamic systems to generate stimulation of seeded cells on these scaffolds, improving and maintaining the cellular growth process in a cell culture. However, Few TE skin products have been clinically translated, and more research is required to produce highly biomimetic skin substitutes that mimic the native elasticity of skin in a controlled manner. Therefore, this work will be focused on the fabrication of a novel mechanical system to enhance the TE treatment approaches for the reparation of damaged tissue skin. Aims: To archive this, a soft robotic device will be created to emulate different deformation of skin stress. The design of this soft robot will allow the attachment of scaffolds, which will then be mechanically actuated. This will provide a novel and highly adaptable platform for dynamic cell culture. Methods: Novel, low-cost soft robot is fabricated via 3D printed moulds and silicone. A low cost, electro-mechanical device was constructed to actuate the soft robot through the controlled combination of positive and negative air pressure to control the different state of movements. Mechanical tests were conducted to assess the performance and calibration of each electronic component. Similarly, pressure-displacement test was performed on scaffolds, which were attached to the soft robot, applying various mechanical loading regimes. Lastly, digital image correlation test was performed to obtain strain distributions over the soft robot’s surface. Results: The control system can control and stabilise positive pressure changes for long hours. Similarly, pressure-displacement test demonstrated that scaffolds with 5µm of diameter and wavy geometry can displace at 100%, applying a maximum pressure of 1.5 PSI. Lastly, during the inflation state, the displacement of silicone was measured using DIC method, and this showed a parameter of 4.78 mm and strain of 0.0652. Discussion And Conclusion: The developed soft robot system provides a novel and low-cost platform for the dynamic actuation of tissue scaffolds with a target towards dynamic cell culture.

Keywords: soft robot, tissue engineering, mechanical stimulation, dynamic cell culture, bioreactor

Procedia PDF Downloads 96
186 Preparation of Electrospun PLA/ENR Fibers

Authors: Jaqueline G. L. Cosme, Paulo H. S. Picciani, Regina C. R. Nunes

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Electrospinning is a technique for the fabrication of nanoscale fibers. The general electrospinning system consists of a syringe filled with polymer solution, a syringe pump, a high voltage source and a grounded counter electrode. During electrospinning a volumetric flow is set by the syringe pump and an electric voltage is applied. This forms an electric potential between the needle and the counter electrode (collector plate), which results in the formation of a Taylor cone and the jet. The jet is moved towards the lower potential, the counter electrode, wherein the solvent of the polymer solution is evaporated and the polymer fiber is formed. On the way to the counter electrode, the fiber is accelerated by the electric field. The bending instabilities that occur form a helical loop movements of the jet, which result from the coulomb repulsion of the surface charge. Trough bending instabilities the jet is stretched, so that the fiber diameter decreases. In this study, a thermoplastic/elastomeric binary blend of non-vulcanized epoxidized natural rubber (ENR) and poly(latic acid) (PLA) was electrospun using polymer solutions consisting of varying proportions of PCL and NR. Specifically, 15% (w/v) PLA/ENR solutions were prepared in /chloroform at proportions of 5, 10, 25, and 50% (w/w). The morphological and thermal properties of the electrospun mats were investigated by scanning electron microscopy (SEM) and differential scanning calorimetry analysis. The SEM images demonstrated the production of micrometer- and sub-micrometer-sized fibers with no bead formation. The blend miscibility was evaluated by thermal analysis, which showed that blending did not improve the thermal stability of the systems.

Keywords: epoxidized natural rubber, poly(latic acid), electrospinning, chemistry

Procedia PDF Downloads 410
185 Multi-Index Performance Investigation of Rubberized Reclaimed Asphalt Mixture

Authors: Ling Xu, Giuseppe Loprencipe, Antonio D'Andrea

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Asphalt pavement with recycled and sustainable materials has become the most commonly adopted strategy for road construction, including reclaimed asphalt pavement (RAP) and crumb rubber (CR) from waste tires. However, the adhesion and cohesion characteristics of rubberized reclaimed asphalt pavement were still ambiguous, resulting in deteriorated adhesion behavior and life performance. This research investigated the effect of bonding characteristics on rutting resistance and moisture susceptibility of rubberized reclaimed asphalt pavement in terms of two RAP sources with different oxidation levels and two tire rubber with different particle sizes. Firstly, the binder bond strength (BBS) test and bonding failure distinguishment were conducted to analyze the surface behaviors of binder-aggregate interaction. Then, the compatibility and penetration grade of rubberized RAP binder were evaluated by rotational viscosity test and penetration test, respectively. Hamburg wheel track (HWT) test with high-temperature viscoelastic deformation analysis was adopted, which illustrated the rutting resistance. Additionally, a water boiling test was employed to evaluate the moisture susceptibility of the mixture and the texture features were characterized with the statistical parameters of image colors. Finally, the colloid structure model of rubberized RAP binder with surface interaction was proposed, and statistical analysis was established to release the correlation among various indexes. This study concluded that the gel-phase colloid structure and molecular diffusion of the free light fraction would affect the surface interpretation with aggregate, determining the bonding characteristic of rubberized RAP asphalt.

Keywords: bonding characteristics, reclaimed asphalt pavement, rubberized asphalt, sustainable material

Procedia PDF Downloads 62
184 Mobile Network Users Amidst Ultra-Dense Networks in 5G Using an Improved Coordinated Multipoint (CoMP) Technology

Authors: Johnson O. Adeogo, Ayodele S. Oluwole, O. Akinsanmi, Olawale J. Olaluyi

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In this 5G network, very high traffic density in densely populated areas, most especially in densely populated areas, is one of the key requirements. Radiation reduction becomes one of the major concerns to secure the future life of mobile network users in ultra-dense network areas using an improved coordinated multipoint technology. Coordinated Multi-Point (CoMP) is based on transmission and/or reception at multiple separated points with improved coordination among them to actively manage the interference for the users. Small cells have two major objectives: one, they provide good coverage and/or performance. Network users can maintain a good quality signal network by directly connecting to the cell. Two is using CoMP, which involves the use of multiple base stations (MBS) to cooperate by transmitting and/or receiving at the same time in order to reduce the possibility of electromagnetic radiation increase. Therefore, the influence of the screen guard with rubber condom on the mobile transceivers as one major piece of equipment radiating electromagnetic radiation was investigated by mobile network users amidst ultra-dense networks in 5g. The results were compared with the same mobile transceivers without screen guards and rubber condoms under the same network conditions. The 5 cm distance from the mobile transceivers was measured with the help of a ruler, and the intensity of Radio Frequency (RF) radiation was measured using an RF meter. The results show that the intensity of radiation from various mobile transceivers without screen guides and condoms was higher than the mobile transceivers with screen guides and condoms when call conversation was on at both ends.

Keywords: ultra-dense networks, mobile network users, 5g, coordinated multi-point.

Procedia PDF Downloads 103
183 Comparison of Mechanical Properties of Three Different Orthodontic Latex Elastic Bands Leached with NaOH Solution

Authors: Thipsupar Pureprasert, Niwat Anuwongnukroh, Surachai Dechkunakorn, Surapich Loykulanant, Chaveewan Kongkaew, Wassana Wichai

Abstract:

Objective: Orthodontic elastic bands made from natural rubber continue to be commonly used due to their favorable characteristics. However, there are concerns associated cytotoxicity due to harmful components released during conventional vulcanization (sulfur-based method). With the co-operation of The National Metal and Materials Technology Center (MTEC) and Faculty of Dentistry Mahidol University, a method was introduced to reduce toxic components by leaching the orthodontic elastic bands with NaOH solution. Objectives: To evaluate the mechanical properties of Thai and commercial orthodontic elastic brands (Ormco and W&H) leached with NaOH solution. Material and methods: Three elastic brands (N =30, size ¼ inch, 4.5 oz.) were tested for mechanical properties in terms of initial extension force, residual force, force loss, breaking strength and maximum displacement using a Universal Testing Machine. Results : Force loss significantly decreased in Thai-LEACH and W&H-LEACH, whereas the values increased in Ormco-LEACH (P < 0.05). The data exhibited a significantly decrease in breaking strength with Thai-LEACH and Ormco-LEACH, whereas all 3 brands revealed a significantly decrease in maximum displacement with the leaching process (P < 0.05). Conclusion: Leaching with NaOH solution is a new method, which can remove toxic components from orthodontic latex elastic bands. However, this process can affect their mechanical properties. Leached elastic bands from Thai had comparable properties with Ormco and have potential to be developed as a promising product.

Keywords: leaching, orthodontic elastics, natural rubber latex, orthodontic

Procedia PDF Downloads 271
182 Softening Finishing: Teaching and Learning Materials

Authors: C.W. Kan

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Softening applied on textile products based on several reasons. First, the synthetic detergent removes natural oils and waxes, thus lose the softness. Second, compensate the harsh handle of resin finishing. Also, imitate natural fibres and improve the comfort of fabric are the reasons to apply softening. There are different types of softeners for softening finishing of textiles, nonionic softener, anionic softener, cationic softener and silicone softener. The aim of this study is to illustrate the proper application of different softeners and their final softening effect in textiles. The results could also provide guidance note to the students in learning this topic. Acknowledgment: Authors would like to thank the financial support from the Hong Kong Polytechnic University for this work.

Keywords: learning materials, softening, textiles, effect

Procedia PDF Downloads 217
181 Exploration of Industrial Symbiosis Opportunities with an Energy Perspective

Authors: Selman Cagman

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A detailed analysis is made within an organized industrial zone (OIZ) that has 1165 production facilities such as manufacturing of furniture, fabricated metal products (machinery and equipment), food products, plastic and rubber products, machinery and equipment, non-metallic mineral products, electrical equipment, textile products, and manufacture of wood and cork products. In this OIZ, a field study is done by choosing some facilities that can represent the whole OIZ sectoral distribution. In this manner, there are 207 facilities included to the site visit, and there is a 17 questioned survey carried out with each of them to assess their inputs, outputs, and waste amounts during manufacturing processes. The survey result identify that MDF/Particleboard and chipboard particles, textile, food, foam rubber, sludge (treatment sludge, phosphate-paint sludge, etc.), plastic, paper and packaging, scrap metal (aluminum shavings, steel shavings, iron scrap, profile scrap, etc.), slag (coal slag), ceramic fracture, ash from the fluidized bed are the wastes come from these facilities. As a result, there are 5 industrial symbiosis projects established with this study. One of the projects is a 2.840 kW capacity Integrated Biomass Based Waste Incineration-Energy Production Facility running on 35.000 tons/year of MDF particles and chipboard waste. Another project is a biogas plant with 225 tons/year whey, 100 tons/year of sesame husk, 40 tons/year of burnt wafer dough, and 2.000 tons/year biscuit waste. These two plants investment costs and operational costs are given in detail. The payback time of the 2.840 kW plant is almost 4 years and the biogas plant is around 6 years.

Keywords: industrial symbiosis, energy, biogas, waste to incineration

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180 Screening of Commonly Used Reinforcement Materials for Tomb Murals

Authors: Liping Qiu, Xiaofeng Zhang

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In its long history, precious tomb murals suffered from various diseases due to natural and man-made destruction. The key to how to protect tomb murals is how to strengthen and protect the tomb murals. In order to maximize the life of the tomb murals, the artistic, historic, and scientific values of the tomb murals can be continued. In this paper, four kinds of traditional reinforcement materials (silicone acrylic lotion, pure acrylic lotion, polyvinyl acetate lotion, and B72) are selected to reinforce the ground support layer of tomb murals, and the reinforcement effect of each reinforcement material on the ground support layer of murals is compared and analyzed, and the best protection material is obtained.

Keywords: mural, destruction cycle, reinforcement material, disease

Procedia PDF Downloads 132
179 Elastomeric Nanocomposites for Space Applications

Authors: Adriana Stefan, Cristina-Elisabeta Pelin, George Pelin, Maria Daniela Stelescu, Elena Manaila

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Elastomeric composites have been known for a long time, but, to our knowledge, space and the aeronautic community has been directing a special attention to them only in the last decade. The required properties of advanced elastomeric materials used in space applications (such as O-rings) are sealing, abrasion, low-temperature flexibility, the long-term compression set properties, impact resistance and low-temperature thermal stability in different environments, such as ionized radiations. Basically, the elastomeric nanocomposites are composed of a rubber matrix and a wide and varied range of nanofillers, added with the aim of improving the physico-mechanical and elasticity modulus properties of the materials as well as their stability in different environments. The paper presents a partial synthesis of the research regarding the use of silicon carbide in nanometric form and/or organophylized montmorillonite as fillers in butyl rubber matrix. The need of composite materials arose from the fact that stand-alone polymers are ineffective in providing all the superior properties required by different applications. These drawbacks can be diminished or even eliminated by incorporating a new range of additives into the organic matrix, fillers that have important roles in modifying properties of various polymers. A composite material can provide superior and unique mechanical and physical properties because it combines the most desirable properties of its constituents while suppressing their least desirable properties. The commercial importance of polymers and the continuous increase of their use results in the continuous demand for improvement in their properties to meet the necessary conditions. To study the performance of the elastomeric nanocomposites were mechanically tested, it will be tested the qualities of tensile at low temperatures and RT and the behavior at the compression at cryogenic to room temperatures and under different environments. The morphology of specimens will be investigated by optical and scanning electronic microscopy.

Keywords: elastomeric nanocomposites, O-rings, space applications, mechanical properties

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178 Thermo-Oxidative Degradation of Esterified Starch (with Lauric Acid) -Plastic Composite Assembled with Pro-Oxidants and Elastomers

Authors: R. M. S. Sachini Amararathne

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This research is striving to develop a thermo degradable starch plastic compound/ masterbatch for industrial packaging applications. A native corn starch-modified with an esterification reaction of lauric acid is melt blent with an unsaturated elastomer (styrene-butadiene-rubber/styrene-butadiene-styrene). A trace amount of metal salt is added into the internal mixer to study the effect of pro-oxidants in a thermo oxidative environment. Then the granulated polymer composite which is consisted with 80-86% of polyolefin (LLDP/LDPE/PP) as the pivotal agent; is extruded with processing aids, antioxidants and some other additives in a co-rotating twin-screw extruder. The pelletized composite is subjected to compression molding/ Injection molding or blown film extrusion processes to acquire the samples/specimen for tests. The degradation process is explicated by analyzing the results of fourier transform infrared spectroscopy (FTIR) measurements, thermo oxidative aging studies (placing the dumb-bell specimen in an air oven at 70 °C for four weeks of exposure.) governed by tensile and impact strength test reports. Furthermore, the samples were elicited into manifold outdoors to inspect the degradation process. This industrial process is implemented to reduce the volume of fossil-based garbage by achieving the biodegradability and compostability in the natural cycle. Hence the research leads to manufacturing a degradable plastic packaging compound which is now available in the Sri Lankan market.

Keywords: blown film extrusion, compression moulding, polyolefin, pro-oxidant, styrene-butadine-rubber, styrene-butadiene-styrene, thermo oxidative aging, unsaturated elastomer

Procedia PDF Downloads 95
177 Demonstrating a Relationship of Frequency and Weight with Arduino UNO and Visual Basic Program

Authors: Woraprat Chaomuang, Sirikorn Sringern, Pawanrat Chamnanwongsritorn, Kridsada Luangthongkham

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In this study, we have applied a digital scale to demonstrate the electricity concept of changing the capacity (C), due to the weight of an object, as a function of the distance between the conductor plates and the pressing down. By calibrating on standard scales with the Visual Basic program and the Arduino Uno microcontroller board, we can obtain the weight of the object from the frequency (ƒ) that is measured from the electronic circuit (Astable Multivibrator). Our results support the concept, showing a linear correlation between the frequency and weight with an equation y = –0.0112x + 379.78 and the R2 value of 0.95. In addition, the effects of silicone rods shrinkage, permittivity and temperature were also examined and have found to affect various graph patterns observed.

Keywords: Arduino Uno board, frequency, microcontroller board, parallel plate conductor

Procedia PDF Downloads 207
176 Effects of Heat Source Position on Heat Transfer in an Inclined Square Enclosure Filled with Nanofluids

Authors: Khamis Al Kalbani

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The effects of a uniform heat source position on the heat transfer flow inside an inclined square enclosure filled with different types of nanofluids having various shapes of the nanoparticles are investigated numerically following one component thermal equilibrium model. The effects of the Brownian diffusion of the nanoparticles, magnetic field intensity and orientation are taken into consideration in nanofluid modeling. The heat source is placed in the middle of a wall of the enclosure while the opposite wall of it is kept at different temperature. The other walls of the enclosure are kept insulated. The results indicate that the heat source position significantly controls the heat transfer rates of the nanofluids. The distributions of the average heat transfer rates varying the position of the heat source with respect to the geometry inclination angle are calculated for the first time. The outcomes of the present research may be helpful for designing solar thermal collectors, radiators, building insulators and advanced cooling of a nuclear system.

Keywords: heat source, inclined, square enclosure, nanofluids

Procedia PDF Downloads 306
175 Bactericidal Efficacy of Quaternary Ammonium Compound on Carriers with Food Additive Grade Calcium Hydroxide against Salmonella Infantis and Escherichia coli

Authors: M. Shahin Alam, Satoru Takahashi, Mariko Itoh, Miyuki Komura, Mayuko Suzuki, Natthanan Sangsriratanakul, Kazuaki Takehara

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Cleaning and disinfection are key components of routine biosecurity in livestock farming and food processing industry. The usage of suitable disinfectants and their proper concentration are important factors for a successful biosecurity program. Disinfectants have optimum bactericidal and virucidal efficacies at temperatures above 20°C, but very few studies on application and effectiveness of disinfectants at low temperatures have been done. In the present study, the bactericidal efficacies of food additive grade calcium hydroxide (FdCa(OH)), quaternary ammonium compound (QAC) and their mixture, were investigated under different conditions, including time, organic materials (fetal bovine serum: FBS) and temperature, either in suspension or in carrier test. Salmonella Infantis and Escherichia coli, which are the most prevalent gram negative bacteria in commercial poultry housing and food processing industry, were used in this study. Initially, we evaluated these disinfectants at two different temperatures (4°C and room temperature (RT) (25°C ± 2°C)) and 7 contact times (0, 5 and 30 sec, 1, 3, 20 and 30 min), with suspension tests either in the presence or absence of 5% FBS. Secondly, we investigated the bactericidal efficacies of these disinfectants by carrier tests (rubber, stainless steel and plastic) at same temperatures and 4 contact times (30 sec, 1, 3, and 5 min). Then, we compared the bactericidal efficacies of each disinfectant within their mixtures, as follows. When QAC was diluted with redistilled water (dW2) at 1: 500 (QACx500) to obtain the final concentration of didecyl-dimethylammonium chloride (DDAC) of 200 ppm, it could inactivate Salmonella Infantis within 5 sec at RT either with or without 5% FBS in suspension test; however, at 4°C it required 30 min in presence of 5% FBS. FdCa(OH)2 solution alone could inactivate bacteria within 1 min both at RT and 4°C even with 5% FBS. While FdCa(OH)2 powder was added at final concentration 0.2% to QACx500 (Mix500), the mixture could inactivate bacteria within 30 sec and 5 sec, respectively, with or without 5% FBS at 4°C. The findings from the suspension test indicated that low temperature inhibited the bactericidal efficacy of QAC, whereas Mix500 was effective, regardless of short contact time and low temperature, even with 5% FBS. In the carrier test, single disinfectant required bit more time to inactivate bacteria on rubber and plastic surfaces than on stainless steel. However, Mix500 could inactivate S. Infantis on rubber, stainless steel and plastic surfaces within 30 sec and 1 min, respectively, at RT and 4°C; but, for E. coli, it required only 30 sec at both temperatures. So, synergistic effects were observed on different carriers at both temperatures. For a successful enhancement of biosecurity during winter, the disinfectants should be selected that could have short contact times with optimum efficacy against the target pathogen. The present study findings help farmers to make proper strategies for application of disinfectants in their livestock farming and food processing industry.

Keywords: carrier, food additive grade calcium hydroxide (FdCa(OH)₂), quaternary ammonium compound, synergistic effects

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174 Comparison of Fuel Properties from Species of Microalgae and Selected Second-Generation Oil Feedstocks

Authors: Andrew C. Eloka Eboka, Freddie L. Inambao

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Comparative investigation and assessment of microalgal technology as a biodiesel production option was studied alongside other second generation feedstocks. This was carried out by comparing the fuel properties of species of Chlorella vulgaris, Duneliella spp, Synechococus spp and Senedesmus spp with the feedstock of Jatropha (ex-basirika variety), Hura crepitans, rubber and Natal mahogany seed oils. The micro-algae were cultivated in an open pond using a photobioreactor (New Brunsink set-up model BF-115 Bioflo/CelliGen made in the US) with operating parameters: 14L capacity, working volume of 7.5L media, including 10% inoculum, at optical density of 3.144 @540nm and light intensity of 200 lux, for 23 and 16 days respectively. Various produced/accumulated biomasses were harvested by draining, flocculation, centrifugation, drying and then subjected to lipid extraction processes. The oils extracted from the algae and feedstocks were characterised and used to produce biodiesel fuels, by the transesterification method, using modified optimization protocol. Fuel properties of the final biodiesel products were evaluated for chemo-physical and fuel properties. Results revealed Chlorella vulgaris as the best strain for biomass cultivation, having the highest lipid productivity (5.2mgL-1h-1), the highest rate of CO2 absorption (17.85mgL-1min-1) and the average carbon sequestration in the form of CO2 was 76.6%. The highest biomass productivity was 35.1mgL-1h-1 (Chlorella), while Senedesmus had the least output (3.75mgL-1h-1, 11.73mgL-1min-1). All species had good pH value adaptation, ranging from 6.5 to 8.5. The fuel properties of the micro-algal biodiesel in comparison with Jatropha, rubber, Hura and Natal mahogany were within ASTM specification and AGO used as the control. Fuel cultivation from microalgae is feasible and will revolutionise the biodiesel industry.

Keywords: biodiesel, fuel properties, microalgae, second generation, seed oils, feedstock, photo-bioreactor, open pond

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173 Polymer Aerostatic Thrust Bearing under Circular Support for High Static Stiffness

Authors: Sy-Wei Lo, Chi-Heng Yu

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A new design of aerostatic thrust bearing is proposed for high static stiffness. The bearing body, which is mead of polymer covered with metallic membrane, is held by a circular ring. Such a support helps form a concave air gap to grasp the air pressure. The polymer body, which can be made rapidly by either injection or molding is able to provide extra damping under dynamic loading. The smooth membrane not only serves as the bearing surface but also protects the polymer body. The restrictor is a capillary inside a silicone tube. It can passively compensate the variation of load by expanding the capillary diameter for more air flux. In the present example, the stiffness soars from 15.85 N/µm of typical bearing to 349.85 N/µm at bearing elevation 9.5 µm; meanwhile the load capacity also enhances from 346.86 N to 704.18 N.

Keywords: aerostatic, bearing, polymer, static stiffness

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172 Impact of Private Oil Palm Expansion on Indonesia Tropical Forest Deforestation Rate: Case Study in the Province of Riau

Authors: Arzyana Sunkar, Yanto Santosa, Intan Purnamasari, Yohanna Dalimunthe

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A variety of negative allegations have criticized the Indonesian oil palm plantations as being environmentally unfriendly. One of the important allegations thus must be verified is that expansion of Indonesian oil palm plantation has increased the deforestation rate of primary tropical forest. In relation to this, a research was conducted to study the origin or history of the status and land use of 8 private oil palm plantations (with a total of 46,372.38 ha) located in Riau Province. Several methods were employed: (1) conducting analysis of overlay maps between oil palm plantation studied with the 1986 Forest Map Governance Agreement (TGHK) and the 1994 and 2014 Riau Provincial Spatial Plans(RTRWP); (2) studying the Cultivation Right on Land (HGU) documents including the Forestry Ministerial Decree on the release of forest area and (3) interpretation of lands at imagery of bands 542, covering 3 years before and after the oil palm industries operated. In addition, field cross-checked, and interviews were conducted with National Land Agency, Plantation and Forestry Office and community figures. The results indicated that as much as 1.95% of the oil palm plantations under study were converted from production forest, 30.34% from limited production forest and 67.70% from area for other usage /conversion production forest. One year prior to the establishment of the plantations, the land cover types comprised of rubber plantations (49.96%), secondary forest (35.99%), bare land (10.17%), shrubs (3.03%) and mixed dryland farming-shrubs (0.84%), whereas the land use types comprised of 35.99% forest concession areas, 14.04% migrants dryland farms, and 49.96% Cultivation Right on Land of other companies. These results indicated that most of the private oil palm plantations under study, resulted from the conversion of production forests and the previous land use were not primary forest but rubber plantations and secondary forests.

Keywords: land cover types, land use history, primary forest, private oil palm plantations

Procedia PDF Downloads 238
171 Study on Reusable, Non Adhesive Silicone Male External Catheter: Clinical Proof of Study and Quality Improvement Project

Authors: Venkata Buddharaju, Irene Mccarron, Hazel Alba

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Introduction: Male external catheters (MECs) are commonly used to collect and drain urine. MECs are increasingly used in acute care, long-term acute care hospitals, and nursing facilities, and in other patients as an alternative to invasive urinary catheters to reduce catheter-associated urinary tract infections (CAUTI).MECs are also used to avoid the need for incontinence pads and diapers. Most of the Male External Catheters are held in place by skin adhesive, with the exception of a few, which uses a foam strap clamp around the penile shaft. The adhesive condom catheters typically stay for 24 hours or less. It is also a common practice that extra skin adhesive tape is wrapped around the condom catheter for additional security of the device. The fixed nature of the adhesive will not allow the normal skin expansion of penile size over time. The adhesive can cause skin irritation, redness, erosion, and skin damage. Acanthus condom catheter (ACC) is a patented, specially designed, stretchable silicone catheter without adhesive, adapts to the size and contour of the penis. It is held in place with a single elastic strap that wraps around the lower back and tied to the opposite catheter ring holescriss cross. It can be reused for up to 5 days on the same patient after daily cleaning and washingpotentially reducing cost. Methods: The study was conducted from September 17th to October 8th, 2020. The nursing staff was educated and trained on how to use and reuse the catheter. After identifying five (5) appropriate patients, the catheter was placed and maintained by nursing staff. The data on the ease of use, leak, and skin damage were collected and reported by nurses to the nursing education department of the hospital for analysis. Setting: RML Chicago, long-term acute care hospital, an affiliate of Loyola University Medical Center, Chicago, IL USA. Results: The data showed that the catheter was easy to apply, remove, wash and reuse, without skin problems or urine infections. One patient had used for 16 days after wash, reuse, and replacement without any urine leak or skin issues. A minimal leak was observed on two patients. Conclusion: Acanthus condom catheter was easy to use, functioned well with minimal or no leak during use and reuse. The skin was intact in all patients studied. There were no urinary tract infections in any of the studied patients.

Keywords: CAUTI, male external catheter, reusable, skin adhesive

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170 Attitudes of the Indigenous People from Providencia, Amazon towards the Bora Language

Authors: Angela Maria Sarmiento

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Since the end of the 19th century, the Bora people struggled to survive two stages of colonial domination, which resulted in situations of forced contact with the Western world. Their inclusion in global designs altered the configuration of their local spaces and social practices; thus the Bora language was affected and prone to transformation. This descriptive, interpretive study, within the indigenous and minoritized groups’ research field, aimed at analysing the linguistic attitudes as well as the contextual situation of the Bora language in Providencia, an ancestral territory and a speech community contained in the midst of the Colombian Amazon rainforest. Through the inquiry of their sociolinguistic practices, this study also considered the effects of the course of events derived from the rubber exploitation in the late 19th century, and the arrival of the Capuchin’s mission in the early 20th century. The methodology used in this study had an ethnographic approach, which allowed the researcher to study the social phenomena from the perspective of the participants. Fieldwork, diary, field notes, and semi-structured interviews were conducted and then triangulated with participant observations. The findings of this study suggest that there is a transition from current individual bilingualism towards Spanish monolingualism; this is enhanced by the absence of a functional distribution of the three varieties (Bora, Huitoto, and Spanish). Also, the positive attitudes towards the Spanish language are based on its functionality while positive attitudes towards the Bora language mostly refer to pride and identity. Negative attitudes are only directed towards the Bora language. In the search for the roots of these negative attitudes, appeared the traumatic experiences of the rubber exploitation and the indigenous experiences at the capuchin’s boarding school. Finally, the situation of the Bora language can be configured as a social fact strongly connected to previous years of colonial dominations and to the current and continuous incursion of new global-colonial designs.

Keywords: Bora language, language contact, linguistic attitudes, speech communities

Procedia PDF Downloads 147
169 Flashover Detection Algorithm Based on Mother Function

Authors: John A. Morales, Guillermo Guidi, B. M. Keune

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Electric Power supply is a crucial topic for economic and social development. Power outages statistics show that discharges atmospherics are imperative phenomena to produce those outages. In this context, it is necessary to correctly detect when overhead line insulators are faulted. In this paper, an algorithm to detect if a lightning stroke generates or not permanent fault on insulator strings is proposed. On top of that, lightning stroke simulations developed by using the Alternative Transients Program, are used. Based on these insights, a novel approach is designed that depends on mother functions analysis corresponding to the given variance-covariance matrix. Signals registered at the insulator string are projected on corresponding axes by the means of Principal Component Analysis. By exploiting these new axes, it is possible to determine a flashover characteristic zone useful to a good insulation design. The proposed methodology for flashover detection extends the existing approaches for the analysis and study of lightning performance on transmission lines.

Keywords: mother function, outages, lightning, sensitivity analysis

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168 The Attitudinal Effects of Dental Hygiene Students When Changing Conventional Practices of Preventive Therapy in the Dental Hygiene Curriculum

Authors: Shawna Staud, Mary Kaye Scaramucci

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Objective: Rubber cup polishing has been a traditional method of preventative therapy in dental hygiene treatment. Newer methods such as air polishing have changed the way dental hygiene care is provided, yet this technique has not been embraced by students in the program nor by practitioners in the workforce. Students entering the workforce tend to follow office protocol and are limited in confidence to introduce technologies learned in the curriculum. This project was designed to help students gain confidence in newer skills and encourage private practice settings to adopt newer technologies for patient care. Our program recently introduced air polishing earlier in the program before the rubber cup technique to determine if students would embrace the technology to become leading-edge professionals when they enter the marketplace. Methods: The class of 2022 was taught the traditional method of polishing in the first-year curriculum and air polishing in the second-year curriculum. The class of 2023 will be taught the air polishing method in the first-year curriculum and the traditional method of polishing in the second-year curriculum. Pre- and post-graduation survey data will be collected from both cohorts. Descriptive statistics and pre and post-paired t-tests with alpha set at .05 to compare pre and post-survey results will be used to assess data. Results: This study is currently in progress, with a completion date of October 2023. The class of 2022 completed the pre-graduation survey in the spring of 2022. The post-gradation survey will be sent out in October 2022. The class of 2023 cohort will be surveyed in the spring of 2023 and October 2023. Conclusion: Our hypothesis is students who are taught air polishing first will be more inclined to adopt that skill in private practice, thereby embracing newer technology and improving oral health care.

Keywords: luggage handling system at world’s largest pilgrimage center

Procedia PDF Downloads 102
167 Investigation of Solvent Effect on Viscosity of Lubricant in Disposable Medical Devices

Authors: Hamed Bagheri, Seyd Javid Shariati

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The effects of type and amount of solvent on lubricant which is used in disposable medical devices are investigated in this article. Two kinds of common solvent, n-Hexane and n-Heptane, are used. The mechanical behavior of syringe has shown that n-Heptane has better mixing ratio and also more effective spray process in the barrel of syringe than n-Hexane because of similar solubility parameter to silicon oil. The results revealed that movement of plunger in the barrel increases when pure silicone is used because non-uniform film is created on the surface of barrel, and also, it seems that the form of silicon is converted from oil to gel due to sterilization process. The results showed that the convenient mixing ratio of solvent/lubricant oil is 80/20.

Keywords: disposal medical devices, lubricant oil, solvent effect, solubility parameter

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166 Loss of the Skin Barrier after Dermal Application of the Low Molecular Methyl Siloxanes: Volatile Methyl Siloxanes, VMS Silicones

Authors: D. Glamowska, K. Szymkowska, K. Mojsiewicz- Pieńkowska, K. Cal, Z. Jankowski

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Introduction: The integrity of the outermost layer of skin (stratum corneum) is vital to the penetration of various compounds, including toxic substances. Barrier function of skin depends of its structure. The barrier function of the stratum corneum is provided by patterned lipid lamellae (binlayer). However, a lot of substances, including the low molecular methyl siloxanes (volatile methyl siloxanes, VMS) have an impact on alteration the skin barrier due to damage of stratum corneum structure. VMS belong to silicones. They are widely used in the pharmaceutical as well as cosmetic industry. Silicones fulfill the role of ingredient or excipient in medicinal products and the excipient in personal care products. Due to the significant human exposure to this group of compounds, an important aspect is toxicology of the compounds and safety assessment of products. Silicones in general opinion are considered as a non-toxic substances, but there are some data about their negative effect on living organisms through the inhaled or oral application. However, the transdermal route has not been described in the literature as a possible alternative route of penetration. The aim of the study was to verify the possibility of penetration of the stratum corneum, further permeation into the deeper layers of the skin (epidermis and dermis) as well as to the fluid acceptor by VMS. Methods: Research methodology was developed based on the OECD and WHO guidelines. In ex-vivo study, the fluorescence microscope and ATR FT-IR spectroscopy was used. The Franz- type diffusion cells were used to application of the VMS on the sample of human skin (A=0.65 cm) for 24h. The stratum corneum at the application site was tape-stripped. After separation of epidermis, relevant dyes: fluorescein, sulforhodamine B, rhodamine B hexyl ester were put on and observations were carried in the microscope. To confirm the penetration and permeation of the cyclic or linear VMS and thus the presence of silicone in the individual layers of the skin, spectra ATR FT-IR of the sample after application of silicone and H2O (control sample) were recorded. The research included comparison of the intesity of bands in characteristic positions for silicones (1263 cm-1, 1052 cm-1 and 800 cm-1). Results: and Conclusions The results present that cyclic and linear VMS are able to overcome the barrier of the skin. Influence of them on damage of corneocytes of the stratum corneum was observed. This phenomenon was due to distinct disturbances in the lipid structure of the stratum corneum. The presence of cyclic and linear VMS were identified in the stratum corneum, epidermis as well as in the dermis by both fluorescence microscope and ATR FT-IR spectroscopy. This confirms that the cyclic and linear VMS can penetrate to stratum corneum and permeate through the human skin layers. Apart from this they cause changes in the structure of the skin. Results show to possible absorption into the blood and lymphathic vessels by the VMS with linear and cyclic structure.

Keywords: low molecular methyl siloxanes, volatile methyl siloxanes, linear and cyclic siloxanes, skin penetration, skin permeation

Procedia PDF Downloads 344
165 Reduce of the Consumption of Industrial Kilns a Pottery Kiln as Example, Recovery of Lost Energy Using a System of Heat Exchangers and Modeling of Heat Transfer Through the Walls of the Kiln

Authors: Maha Bakkari, Fatiha Lemmeni, Rachid Tadili

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In this work, we present some characteristics of the furnace studied, its operating principle and the experimental measurements of the evolutions of the temperatures inside and outside the walls of the This work deals with the problem of energy consumption of pottery kilns whose energy consumption is relatively too high. In this work, we determined the sources of energy loss by studying the heat transfer of a pottery furnace, we proposed a recovery system to reduce energy consumption, and then we developed a numerical model modeling the transfers through the walls of the furnace and to optimize the insulation (reduce heat losses) by testing multiple insulators. The recovery and reuse of energy recovered by the recovery system will present a significant gain in energy consumption of the oven and cooking time. This research is one of the solutions that helps reduce the greenhouse effect of the planet earth, a problem that worries the world.

Keywords: recovery lost energy, energy efficiency, modeling, heat transfer

Procedia PDF Downloads 86
164 Design, Fabrication and Analysis of Molded and Direct 3D-Printed Soft Pneumatic Actuators

Authors: N. Naz, A. D. Domenico, M. N. Huda

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Soft Robotics is a rapidly growing multidisciplinary field where robots are fabricated using highly deformable materials motivated by bioinspired designs. The high dexterity and adaptability to the external environments during contact make soft robots ideal for applications such as gripping delicate objects, locomotion, and biomedical devices. The actuation system of soft robots mainly includes fluidic, tendon-driven, and smart material actuation. Among them, Soft Pneumatic Actuator, also known as SPA, remains the most popular choice due to its flexibility, safety, easy implementation, and cost-effectiveness. However, at present, most of the fabrication of SPA is still based on traditional molding and casting techniques where the mold is 3d printed into which silicone rubber is cast and consolidated. This conventional method is time-consuming and involves intensive manual labour with the limitation of repeatability and accuracy in design. Recent advancements in direct 3d printing of different soft materials can significantly reduce the repetitive manual task with an ability to fabricate complex geometries and multicomponent designs in a single manufacturing step. The aim of this research work is to design and analyse the Soft Pneumatic Actuator (SPA) utilizing both conventional casting and modern direct 3d printing technologies. The mold of the SPA for traditional casting is 3d printed using fused deposition modeling (FDM) with the polylactic acid (PLA) thermoplastic wire. Hyperelastic soft materials such as Ecoflex-0030/0050 are cast into the mold and consolidated using a lab oven. The bending behaviour is observed experimentally with different pressures of air compressor to ensure uniform bending without any failure. For direct 3D-printing of SPA fused deposition modeling (FDM) with thermoplastic polyurethane (TPU) and stereolithography (SLA) with an elastic resin are used. The actuator is modeled using the finite element method (FEM) to analyse the nonlinear bending behaviour, stress concentration and strain distribution of different hyperelastic materials after pressurization. FEM analysis is carried out using Ansys Workbench software with a Yeon-2nd order hyperelastic material model. FEM includes long-shape deformation, contact between surfaces, and gravity influences. For mesh generation, quadratic tetrahedron, hybrid, and constant pressure mesh are used. SPA is connected to a baseplate that is in connection with the air compressor. A fixed boundary is applied on the baseplate, and static pressure is applied orthogonally to all surfaces of the internal chambers and channels with a closed continuum model. The simulated results from FEM are compared with the experimental results. The experiments are performed in a laboratory set-up where the developed SPA is connected to a compressed air source with a pressure gauge. A comparison study based on performance analysis is done between FDM and SLA printed SPA with the molded counterparts. Furthermore, the molded and 3d printed SPA has been used to develop a three-finger soft pneumatic gripper and has been tested for handling delicate objects.

Keywords: finite element method, fused deposition modeling, hyperelastic, soft pneumatic actuator

Procedia PDF Downloads 90
163 Nuclear Powered UAV for Surveillances and Aerial Photography

Authors: Rajasekar Elangopandian, Anand Shanmugam

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Now-a-days for surveillances unmanned aerial vehicle plays a vital role. Not only for surveillances, aerial photography disaster management and the notice of earth behavior UAV1s envisages meticulously. To reduce the maintenance and fuel nuclear powered Vehicles are greater support. The design consideration is much important for the UAV manufacturing industry and Research and development agency. Eventually design is looking like a pentagon shaped fuselage and black rubber coated paint in order to escape from the enemy radar and other targets. The pentagon shape fuselage has large space to keep the mini nuclear reactor inside and the material is carbon – carbon fiber specially designed by the software called cosmol and hyper mesh 14.2. So the weight consideration will produce the positive result for productivity. The walls of the fuselage are coated with lead and protective shield. A double layer of W/Bi sheet is proposed for radiation protection at the energy range of 70 Kev to 90 Kev. The designed W/bi sheet, only 0.14 mm thick and is 36% light. The properties of the fillers were determined from zeta potential and particle size measurements. The Exposes of the radiation can be attenuated by 3 ways such as minimizing exposure time, Maximizing distance from the radiation source and shielding the whole vehicle. The inside reactor will be switched ON when the UAV starts its cruise. The moderators and the control rods can be inserted by automation technique by newly developed software. The heat generated by the reactor will be used to run the turbine which is fixed inside the UAV called mini turbine with natural rubber composite Shaft radiation shield. Cooling system will be in two mode such as liquid and air cooled. Liquid coolant for the heat regeneration is ordinary water, liquid sodium, helium and the walls are made up of regenerative and radiation protective material. The other components like camera and arms bay will be located at the bottom of the UAV high are specially made products in order to escape from the radiation. They are coated with lead Pb and natural rubber composite material. This technique provides the long rang and endurance for eternal flight mission until we need any changeability of parts or product. This UAV has the special advantage of ` land on String` means it`ll land at electric line to charge the automated electronics. Then the fuel is enriched uranium (< 5% U - 235) contains hundreds of fuel pins. This technique provides eternal duty for surveillances and aerial photography. The landing of the vehicle is ease of operation likewise the takeoff is also easier than any other mechanism which present in nowadays. This UAV gives great immense and immaculate technology for surveillance and target detecting and smashing the target.

Keywords: mini turbine, liquid coolant for the heat regeneration, in order to escape from the radiation, eternal flight mission, it`ll land at electric line

Procedia PDF Downloads 410
162 Sustainable Manufacturing of Concentrated Latex and Ribbed Smoked Sheets in Sri Lanka

Authors: Pasan Dunuwila, V. H. L. Rodrigo, Naohiro Goto

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Sri Lanka is one the largest natural rubber (NR) producers of the world, where the NR industry is a major foreign exchange earner. Among the locally manufactured NR products, concentrated latex (CL) and ribbed smoked sheets (RSS) hold a significant position. Furthermore, these products become the foundation for many products utilized by the people all over the world (e.g. gloves, condoms, tires, etc.). Processing of CL and RSS costs a significant amount of material, energy, and workforce. With this background, both manufacturing lines have immensely challenged by waste, low productivity, lack of cost efficiency, rising cost of production, and many environmental issues. To face the above challenges, the adaptation of sustainable manufacturing measures that use less energy, water, materials, and produce less waste is imperative. However, these sectors lack comprehensive studies that shed light on such measures and thoroughly discuss their improvement potentials from both environmental and economic points of view. Therefore, based on a study of three CL and three RSS mills in Sri Lanka, this study deploys sustainable manufacturing techniques and tools to uncover the underlying potentials to improve performances in CL and RSS processing sectors. This study is comprised of three steps: 1. quantification of average material waste, economic losses, and greenhouse gas (GHG) emissions via material flow analysis (MFA), material flow cost accounting (MFCA), and life cycle assessment (LCA) in each manufacturing process, 2. identification of improvement options with the help of Pareto and What-if analyses, field interviews, and the existing literature; and 3. validation of the identified improvement options via the re-execution of MFA, MFCA, and LCA. With the help of this methodology, the economic and environmental hotspots, and the degrees of improvement in both systems could be identified. Results highlighted that each process could be improved to have less waste, monetary losses, manufacturing costs, and GHG emissions. Conclusively, study`s methodology and findings are believed to be beneficial for assuring the sustainable growth not only in Sri Lankan NR processing sector itself but also in NR or any other industry rooted in other developing countries.

Keywords: concentrated latex, natural rubber, ribbed smoked sheets, Sri Lanka

Procedia PDF Downloads 261
161 Feature Evaluation and Applications of Various Advanced Conductors with High Conductivity and Low Flash in Overhead Lines

Authors: Atefeh Pourshafie, Homayoun Bakhtiari

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In power transmission lines, electricity conductors are main tools to carry electric power. Thus, other devices such as shield wires, insulators, towers, foundations etc. should be designed in a way that the conductors be able to successfully do their task which is appropriate power delivery to the customers. Non-stop increase of energy demand has led to saturated capacity of transmission lines which, in turn, causing line flash to exceed acceptable limits in some points. An approach which may be used to solve this issue is replacement of current conductors with new ones having the capability of withstanding higher heating such that reduced flash would be observed when heating increases. These novel conductors are able to transfer higher currents and operate in higher heating conditions while line flash will remain within standard limits. In this paper, we will attempt to introduce three types of advanced overhead conductors and analyze the replacement of current conductors by new ones technically and economically in transmission lines. In this regard, progressive conductors of transmission lines are introduced such as ACC (Aluminum Conductor Composite Core), AAAC-UHC (Ultra High Conductivity, All Aluminum Alloy Conductors), and G(Z)TACSR-Gap Type.

Keywords: ACC, AAAC-UHC, gap type, transmission lines

Procedia PDF Downloads 269
160 A Review on Application of Waste Tire in Concrete

Authors: M. A. Yazdi, J. Yang, L. Yihui, H. Su

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The application of recycle waste tires into civil engineering practices, namely asphalt paving mixtures and cementbased materials has been gaining ground across the world. This review summarizes and compares the recent achievements in the area of plain rubberized concrete (PRC), in details. Different treatment methods have been discussed to improve the performance of rubberized Portland cement concrete. The review also includes the effects of size and amount of tire rubbers on mechanical and durability properties of PRC. The microstructure behaviour of the rubberized concrete was detailed.

Keywords: waste rubber aggregates, microstructure, treatment methods, size and content effects

Procedia PDF Downloads 332
159 Chip Less Microfluidic Device for High Throughput Liver Spheroid Generation

Authors: Sourita Ghosh, Falguni Pati, Suhanya Duraiswamy

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Spheroid, a simple three-dimensional cellular aggregate, allows us to simulate the in-vivo complexity of cellular signaling and interactions in greater detail than traditional 2D cell culture. It can be used as an in-vitro model for drug toxicity testing, tumor modeling and many other such applications specifically for cancer. Our work is focused on the development of an affordable, user-friendly, robust, reproducible, high throughput microfluidic device for water in oil droplet production, which can, in turn, be used for spheroids manufacturing. Here, we have investigated the droplet breakup between two non-Newtonian fluids, viz. silicone oil and decellularized liver matrix, which acts as our extra cellular matrix (ECM) for spheroids formation. We performed some biochemical assays to characterize the liver ECM, as well as rheological studies on our two fluids and observed a critical dependence of capillary number (Ca) on droplet breakup and homogeneous drop formation

Keywords: chip less, droplets, extracellular matrix, liver spheroid

Procedia PDF Downloads 89
158 Characteristics Influencing Response of a Base Isolated Building

Authors: Ounis Hadj Mohamed, Ounis Abdelhafid

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In order to illustrate the effect of damping on the response of a base-isolated building, a parametric study is led, taking into account the progressive variation of the damping ratio (10% to 30%) under different types of seismic excitations (near and far field). A time history analysis is used to determine the response of the structure in terms of relative displacement and understory drift at various levels of the building. Thus, the results show that the efficiency of the isolator increases with the assumed damping ratio, provided that this latter is less or equal to 20%. Beyond this value, the isolator becomes less convenient. Furthermore, a strong deviation of energy capacity by the LRB (Lead Rubber Bearing) system is recorded.

Keywords: damping, base isolation, LRB, seismic excitation, hysteresis

Procedia PDF Downloads 414