Search results for: friction surfaces of airport emergency plan

Authors: Cristina Diaz, Lucia Perez-Gandarillas, Gonzalo Garcia-Fuentes, Simone Visigalli, Roberto Canziani, Giuseppe Di Florio, Paolo Gronchi

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During their lifetime, industrial machines are often subjected to chemical, mechanical and thermal extreme conditions. In some cases, the loss of efficiency comes from the degradation of the surface as a result of its exposition to abrasive environments that can cause wear. This is a common problem to be solved in industries of diverse nature such as food, paper or concrete industries, among others. For this reason, a good selection of the material is of high importance. In the machine design context, stainless steels such as AISI 304 and 316 are widely used. However, the severity of the external conditions can require additional protection for the steel and sometimes coating solutions are demanded in order to extend the lifespan of these materials. Therefore, the development of effective coatings with high wear resistance is of utmost technological relevance. In this research, bilayer coatings made of Titanium-Tantalum, Titanium-Niobium, Titanium-Hafnium, and Titanium-Zirconium have been developed using magnetron sputtering configuration by PVD (Physical Vapor Deposition) technology. Their tribological behavior has been measured and evaluated under different environmental conditions. Two kinds of steels were used as substrates: AISI 304, AISI 316. For the comparison with these materials, titanium alloy substrate was also employed. Regarding the characterization, wear rate and friction coefficient were evaluated by a tribo-tester, using a pin-on-ball configuration with different lubricants such as tomato sauce, wine, olive oil, wet compost, a mix of sand and concrete with water and NaCl to approximate the results to real extreme conditions. In addition, topographical images of the wear tracks were obtained in order to get more insight of the wear behavior and scanning electron microscope (SEM) images were taken to evaluate the adhesion and quality of the coating. The characterization was completed with the measurement of nanoindentation hardness and elastic modulus. Concerning the results, thicknesses of the samples varied from 100 nm (Ti-Zr layer) to 1.4 µm (Ti-Hf layer) and SEM images confirmed that the addition of the Ti layer improved the adhesion of the coatings. Moreover, results have pointed out that these coatings have increased the wear resistance in comparison with the original substrates under environments of different severity. Furthermore, nanoindentation hardness results showed an improvement of the elastic strain to failure and a high modulus of elasticity (approximately 200 GPa). As a conclusion, Ti-Ta, Ti-Zr, Ti-Nb, and Ti-Hf are very promising and effective coatings in terms of tribological behavior, improving considerably the wear resistance and friction coefficient of typically used machine materials.

Keywords: coating, stainless steel, tribology, wear

Procedia PDF Downloads 143

Authors: Sanaa I. Abu Alasal, Madleen M. Esbeih, Eman R. Fayyad, Rami S. Gharaibeh, Mostafa Z. Ali, Ahmed A. Freewan, Monther M. Jamhawi

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This research proposes a novel reconstruction protocol for restoring missing surfaces and low-quality edges and shapes in photos of artifacts at historical sites. The protocol starts with the extraction of a cloud of points. This extraction process is based on four subordinate algorithms, which differ in the robustness and amount of resultant. Moreover, they use different -but complementary- accuracy to some related features and to the way they build a quality mesh. The performance of our proposed protocol is compared with other state-of-the-art algorithms and toolkits. The statistical analysis shows that our algorithm significantly outperforms its rivals in the resultant quality of its object files used to reconstruct the desired model.

Keywords: meshes, point clouds, surface reconstruction protocols, 3D reconstruction

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Authors: Opeyemi Fadipe, Masud Salimian

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The COVID-19 pandemic has introduced a new normal into the world; online teaching is now the most used method of teaching over the face to face meeting. With the emergency of these teaching, online-teaching has been improved over time and with more technological advancement tools introduced. Practical courses are more demanding to teach because it requires the physical presence of the student as well as a demonstration of the equipment. In this study, a case of Lagos State University thermofluid practical was the understudy. A survey was done and give to a sample of students to fill. The result showed that the blend-approach is better for practical course teaching. Software simulation of the equipment used to conduct practical should be encouraged in the future.

Keywords: COVID-19, online teaching, t-distribution, thermofluid

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Authors: Gerd Wilsch, Tobias Guenther, Tobias Voelker

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In view of the ageing of vital infrastructure facilities, a reliable condition assessment of concrete structures is becoming of increasing interest for asset owners to plan timely and appropriate maintenance and repair interventions. For concrete structures, reinforcement corrosion induced by penetrating chlorides is the dominant deterioration mechanism affecting the serviceability and, eventually, structural performance. The determination of the quantitative chloride ingress is required not only to provide valuable information on the present condition of a structure, but the data obtained can also be used for the prediction of its future development and associated risks. At present, wet chemical analysis of ground concrete samples by a laboratory is the most common test procedure for the determination of the chloride content. As the chloride content is expressed by the mass of the binder, the analysis should involve determination of both the amount of binder and the amount of chloride contained in a concrete sample. This procedure is laborious, time-consuming, and costly. The chloride profile obtained is based on depth intervals of 10 mm. LIBS is an economically viable alternative providing chloride contents at depth intervals of 1 mm or less. It provides two-dimensional maps of quantitative element distributions and can locate spots of higher concentrations like in a crack. The results are correlated directly to the mass of the binder, and it can be applied on-site to deliver instantaneous results for the evaluation of the structure. Examples for the application of the method in the laboratory for the investigation of diffusion and migration of chlorides, sulfates, and alkalis are presented. An example for the visualization of the Li transport in concrete is also shown. These examples show the potential of the method for a fast, reliable, and automated two-dimensional investigation of transport processes. Due to the better spatial resolution, more accurate input parameters for model calculations are determined. By the simultaneous detection of elements such as carbon, chlorine, sodium, and potassium, the mutual influence of the different processes can be determined in only one measurement. Furthermore, the application of a mobile LIBS system in a parking garage is demonstrated. It uses a diode-pumped low energy laser (3 mJ, 1.5 ns, 100 Hz) and a compact NIR spectrometer. A portable scanner allows a two-dimensional quantitative element mapping. Results show the quantitative chloride analysis on wall and floor surfaces. To determine the 2-D distribution of harmful elements (Cl, C), concrete cores were drilled, split, and analyzed directly on-site. Results obtained were compared and verified with laboratory measurements. The results presented show that the LIBS method is a valuable addition to the standard procedures - the wet chemical analysis of ground concrete samples. Currently, work is underway to develop a technical code of practice for the application of the method for the determination of chloride concentration in concrete.

Keywords: chemical analysis, concrete, LIBS, spectroscopy

Procedia PDF Downloads 100

Authors: Mary Rose Everan, Michael McCann, Gary Cullen

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International travel journeys, by their nature, incorporate elements provided by multiple service providers such as airlines, rail carriers, airports, and ground handlers. Data needs to be stored by and exchanged between these parties in the process of managing the journey. The fragmented nature of this shared management of mutual clients is a limiting factor in the development of a seamless, hassle-free, end-to-end travel experience. Traditional interlining agreements attempt to facilitate many separate aspects of co-operation between service providers, typically between airlines and, to some extent, intermodal travel operators, including schedules, fares, ticketing, through check-in, and baggage handling. These arrangements rely on pre-agreement. The development of Virtual Interlining - that is, interlining facilitated by a third party (often but not always an airport) without formal pre-agreement by the airlines or rail carriers - demonstrates an underlying demand for a better quality end-to-end travel experience. Blockchain solutions are being explored in a number of industries and offer, at first sight, an immutable, single source of truth for this data, avoiding data conflicts and misinterpretation. Combined with Smart Contracts, they seemingly offer a more robust and dynamic platform for multi-stakeholder ventures, and even perhaps the ability to join and leave consortia dynamically. Applying blockchain to the intermodal interlining space – termed Blocklining in this paper - is complex and multi-faceted because of the many aspects of cooperation outlined above. To explore its potential, this paper concentrates on one particular dimension, that of through baggage interlining.

Keywords: aviation, baggage, blocklining, intermodal, interlining

Procedia PDF Downloads 138

Authors: René Haarhoff

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Consumers are constantly reminded of their responsibility towards the environment in a world where words such as global warming, carbon footprint, recycling or ‘green’’ everything has become common language. What was previously considered to be ordinary practices are in many instances frowned upon today and consumers are expected to individually contribute towards a greener mother earth. However unused recycle bins, single travelers in luxury cars, busy airports and vast deforested areas for new developments tell another story. The question arises whether the everyday man in the street really takes the responsibility to balance the three pillars of sustainability: the planet, its people and profit. Undeniably our activities impact on the environment where a healthy economy is needed in a fast paced global environment. The situation is further gloomed in instances where the consumer has paid for inclusive services which directly impacts on the environment. A prime example of this is the tourism industry: accommodation establishments or resorts include clean, daily washed towels and bedding, large bath tubs, inclusive use of electricity and water to name a few. This research evaluates environmentally friendly practices consumers follow at home and also when on holiday. Respondents at Bloemfontein airport, often using tourism products were included in the study. Results reveal that the majority of respondents state that they are concerned about the environment yet when questioned on donation towards endangered species, switching off lights in hotel rooms or using water sparingly a significant difference in results are evident. From the research results it is evident that consumers do not practice what they preach towards a greener environment.

Keywords: green, environment, consumer, tourism, sustainable practices

Procedia PDF Downloads 337

Authors: Slawomir Pilip, Michal Wasilewski, Daniel Celinski, Leszek Szpakowski, Grzegorz Michalak

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The aim of the study was to evaluate the effectiveness of cardiopulmonary resuscitation taken by Medical Emergency Teams (MET) at the place of an accident including the usage of mechanical chest compression systems. In the period of January-May 2017, there were 137 cases of a sudden cardiac arrest in a chosen region of Eastern Poland with 360.000 inhabitants. Medical records and questionnaires filled by METs were analysed to prove the effectiveness of cardiopulmonary resuscitations that were considered to be effective when an early indication of spontaneous circulation was provided and the patient was taken to hospital. A chest compression system used by METs was applied in 60 cases (Lucas3 - 34 patients; Auto Pulse - 24 patients). The effectiveness of cardiopulmonary resuscitation among patients who were employed a chest compression system was much higher (43,3%) than the manual cardiac massage (36,4%). Thus, the usage of Lucas3 chest compression system resulted in 47% while Auto Pulse was 33,3%. The average ambulance arrival time could have had a significant impact on the subsequent effectiveness of cardiopulmonary resuscitation in these cases. Ambulances equipped with Lucas3 reached the destination within 8 minutes, and those with Auto Pulse needed 12,1 minutes. Moreover, taking effective basic life support (BLS) by bystanders before the ambulance arrival was much more frequent for ambulances with Lucas3 than Auto Pulse. Therefore, the percentage of BLS among the group of patients who were employed Lucas3 by METs was 26,5%, and 20,8% for Auto Pulse. The total percentage of taking BLS by bystanders before the ambulance arrival resulted in 25% of patients who were later applied a chest compression system by METs. Not only was shockable cardiac rhythm obtained in 47% of these cases, but an early indication of spontaneous circulation was also provided in all these patients. Both Lucas3 and Auto Pulse were evaluated to be significantly useful in improving the effectiveness of cardiopulmonary resuscitation by 97% of Medical Emergency Teams. Therefore, implementation of chest compression systems essentially makes the cardiopulmonary resuscitation even more effective. The ambulance arrival time, taking successful BLS by bystanders before the ambulance arrival and the presence of shockable cardiac rhythm determine an early indication of spontaneous circulation among patients after a sudden cardiac arrest.

Keywords: cardiac arrest, effectiveness, mechanical chest compression systems, resuscitation

Procedia PDF Downloads 240

Authors: Vacharee Svamivastu

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This research investigates the application of geometrical relationship to the ancient religious assembly hall (Vihara) housing a reclining Buddha statue of Thailand's Kamphaeng Phet Historical Park. The study utilizes the archaeological and wooden roof structure remains of the Vihara as the prima facie evidence, supplemented with evidence from other active archaeological sites with architectural kinship as well as Buddhist ideology. At present, the wooden roofs of the Vihara fell prey to the elements and there remain only the base, columns and enclosing walls. Unlike typical Viharas whose floor plan are of rectangular shape, the floor plan of the Vihara housing the reclining Buddha is of square configuration of 25x25m. Further observation has revealed the utilization of large laterite boulders as the principal construction material of the assembly hall (Vihara) columns. The laterite columns are of square shape (1x1m) and various heights (H), ranging from 3.50m to 5.50m. The erection of the Vihara required a total of 36 laterite columns. The pattern of columns arrangement is of two rows of inner columns, two rows of outer columns and two rows of verandah columns. The space between pairs of the verandah columns was stacked with laterite blocks of varying sizes to form the Vihara walls with small openings for ventilation. Upon applying the geometrical relationship-grid system to the Vihara, the results reveal that the placement of the columns was deliberately and masterfully undertaken such that the center of the square-shaped Vihara is conspicuously spacious so as to accommodate the sacred reclining Buddha statue. The elegance of the Vihara demonstrates the ingenious application of geometrical relationship to transforming a space into a structure (i.e. Vihara) of architectural and religious significance.

Keywords: geometrical relationship, the religious assembly hall, Vihara, Kamphaeng Phet School of Master Builder

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Authors: Kyle Yatich Terik, Collins Oduor

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The current healthcare system has made healthcare more accessible and efficient by the use of information technology through the implementation of computer algorithms that generate menus based on the diagnosis. While many systems just like these have been created over the years, their main objective is to help healthy individuals calculate their calorie intake and assist them by providing food selections based on a pre-specified calorie. That application has been proven to be useful in some ways, and they are not suitable for monitoring, planning, and managing hospital patients, especially that critical condition their dietary needs. The system also addresses a number of objectives, such as; the main objective is to be able to design, develop and implement an efficient, user-friendly as well as and interactive dietary management system. The specific design development objectives include developing a system that will facilitate a monitoring feature for users using graphs, developing a system that will provide system-generated reports to the users, dietitians, and system admins, design a system that allows users to measure their BMI (Body Mass Index), the system will also provide food template feature that will guide the user on a balanced diet plan. In order to develop the system, further research was carried out in Kenya, Nairobi County, using online questionnaires being the preferred research design approach. From the 44 respondents, one could create discussions such as the major challenges encountered from the manual dietary system, which include no easily accessible information of the calorie intake for food products, expensive to physically visit a dietitian to create a tailored diet plan. Conclusively, the system has the potential of improving the quality of life of people as a whole by providing a standard for healthy living and allowing individuals to have readily available knowledge through food templates that will guide people and allow users to create their own diet plans that consist of a balanced diet.

Keywords: DMS, dietitian, patient, administrator

Procedia PDF Downloads 148

Authors: G. M. Dominguez Almaraz, J. A. Ruiz Vilchez, M. A. Sanchez Miranda

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Ultrasonic fatigue tests have been carried out in the maraging 300 steel. Experimental results show that fatigue endurance under this modality of testing is closely related to the nature and geometrical properties of inclusions present in this alloy. A model was proposed to correlate the ultrasonic fatigue endurance with the nature and geometrical properties of the crack initiation inclusion. Scanning Electron Microscopy analyses were obtained on the fracture surfaces, in order to assess the crack initiation inclusion and to introduce these parameters in the proposed model, with good agreement for the fatigue life prediction.

Keywords: inclusions, ultrasonic fatigue, maraging 300 steel, crack initiation

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Authors: Muhammad Luthfi, Sutikno Sutikno, Purhadi Purhadi

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Weather forecast has necessarily been improved to provide the communities an accurate and objective prediction as well. To overcome such issue, the numerical-based weather forecast was extensively developed to reduce the subjectivity of forecast. Yet the Numerical Weather Predictions (NWPs) outputs are unfortunately issued without taking dynamical weather behavior and local terrain features into account. Thus, NWPs outputs are not able to accurately forecast the weather quantities, particularly for medium and long range forecast. The aim of this research is to aid and extend the development of ensemble forecast for Meteorology, Climatology, and Geophysics Agency of Indonesia. Ensemble method is an approach combining various deterministic forecast to produce more reliable one. However, such forecast is biased and uncalibrated due to its underdispersive or overdispersive nature. As one of the parametric methods, Bayesian Model Averaging (BMA) generates the calibrated ensemble forecast and constructs predictive PDF for specified period. Such method is able to utilize ensemble of any size but does not take spatial correlation into account. Whereas space dependencies involve the site of interest and nearby site, influenced by dynamic weather behavior. Meanwhile, Geostatistical Output Perturbation (GOP) reckons the spatial correlation to generate future weather quantities, though merely built by a single deterministic forecast, and is able to generate an ensemble of any size as well. This research conducts both BMA and GOP to generate the calibrated ensemble forecast for the daily temperature at few meteorological sites nearby Indonesia international airport.

Keywords: Bayesian Model Averaging, ensemble forecast, geostatistical output perturbation, numerical weather prediction, temperature

Procedia PDF Downloads 273

Authors: Alain Kusmoko, Druce Dunne, Huijun Li

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Stellite 6 was deposited by laser cladding on a chromium bearing substrate (P91) with energy inputs of 1 kW (P91-1) and 1.8 kW (P91-1.8). The chemical compositions and microstructures of these coatings were characterized by atomic absorption spectroscopy, optical microscopy and scanning electron microscopy. The microhardness of the coatings was measured and the wear mechanism of the coatings was assessed using a pin-on-plate (reciprocating) wear testing machine. The results showed less cracking and pore development for Stellite 6 coatings applied to the P91 steel substrate with the lower heat input (P91-1). Further, the Stellite coating for P91-1 was significantly harder than that obtained for P91-1.8. The wear test results indicated that the weight loss for P91-1 was much lower than for P91-1.8. It is concluded that the lower hardness of the coating for P91-1.8, together with the softer underlying substrate structure, markedly reduced the wear resistance of the Stellite 6 coating.

Keywords: friction and wear, laser cladding, P91 steel, Stellite 6 coating

Procedia PDF Downloads 429

Authors: Saúl Rivero, Estefanya Marín, Katherine Bolaño, Elena Urán, Juan Yepes, Andrés Cossio

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Medellín is the Colombian city with the best public transport systems in the country, which is made up of two metro lines, five metrocables, two BRT-type bus lines, and a tram. But despite the above, the Aburrá Valley, the area in which the city is located, has about 3000 km of roads, which for the existing population of 3.2 million inhabitants, gives an indicator of 900 meters of road per 1000 inhabitants, which is lower than the country's average, which is approximately 3900 meters. In addition, given that in Medellín, there is approximately one vehicle for every three inhabitants, the problems of congestion and environmental pollution have worsened over the years. In this sense, due to the limitations of physical space, the low public investment in road infrastructure, it is necessary to opt for mobility alternatives according to the above. Among the options for the city, there is what is known as micromobility. Micromobility is understood to be those small and light means of transport that are used for short distances, that use electrical energy, such as skateboards and bicycles. Taking into account the above, in this work, the current state and future of micromobility in the city of Medellín were analyzed, carrying out a prospective analysis, supported by a PEST analysis, but also of the crossed impact matrices; of influence and dependence; and the technique of the actor's game. The analysis was carried out for two future scenarios: one normal and one optimistic. Result of the analysis, it was determined that micromobility as an alternative social practice to mobility in the city of Medellín has favorable conditions since the local government has adopted strategies such as the Metropolitan Bicycle Master Plan of Valle de Aburrá and the plan " Bicycle paths in the city: more public spaces for life,” where a projection of 400 kilometers of bicycle paths was estimated by the year 2030, as for that same year it is expected that 10% of all trips in the region will be in bike mode. The total trip indicator is an achievable goal, while that of the number of kilometers of bike paths would be close to being met.

Keywords: electric vehicles, micromobilty, public transport, sustainable transport

Procedia PDF Downloads 194

Authors: Meiyan Gao, Zongmin Wang, Haibo Yang, Qiuhua Liang

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Under the background of global climate change and rapid development of modern urbanization, the frequency of climate disasters such as extreme precipitation in cities around the world is gradually increasing. In this paper, Hi-PIMS model is used to simulate the "720" flood in Zhengzhou, and the continuous stages of flood resilience are determined with the urban flood stages are divided. The flood resilience curve under the influence of multiple factors were determined and the urban flood toughness was evaluated by combining the results of resilience curves. The flood resilience of urban unit grid was evaluated based on economy, population, road network, hospital distribution and land use type. Firstly, the rainfall data of meteorological stations near Zhengzhou and the remote sensing rainfall data from July 17 to 22, 2021 were collected. The Kriging interpolation method was used to expand the rainfall data of Zhengzhou. According to the rainfall data, the flood process generated by four rainfall events in Zhengzhou was reproduced. Based on the results of the inundation range and inundation depth in different areas, the flood process was divided into four stages: absorption, resistance, overload and recovery based on the once in 50 years rainfall standard. At the same time, based on the levels of slope, GDP, population, hospital affected area, land use type, road network density and other aspects, the resilience curve was applied to evaluate the urban flood resilience of different regional units, and the difference of flood process of different precipitation in "720" rainstorm in Zhengzhou was analyzed. Faced with more than 1,000 years of rainstorm, most areas are quickly entering the stage of overload. The influence levels of factors in different areas are different, some areas with ramps or higher terrain have better resilience, and restore normal social order faster, that is, the recovery stage needs shorter time. Some low-lying areas or special terrain, such as tunnels, will enter the overload stage faster in the case of heavy rainfall. As a result, high levels of flood protection, water level warning systems and faster emergency response are needed in areas with low resilience and high risk. The building density of built-up area, population of densely populated area and road network density all have a certain negative impact on urban flood resistance, and the positive impact of slope on flood resilience is also very obvious. While hospitals can have positive effects on medical treatment, they also have negative effects such as population density and asset density when they encounter floods. The result of a separate comparison of the unit grid of hospitals shows that the resilience of hospitals in the distribution range is low when they encounter floods. Therefore, in addition to improving the flood resistance capacity of cities, through reasonable planning can also increase the flood response capacity of cities. Changes in these influencing factors can further improve urban flood resilience, such as raise design standards and the temporary water storage area when floods occur, train the response speed of emergency personnel and adjust emergency support equipment.

Keywords: urban flood resilience, resilience assessment, hydrodynamic model, resilience curve

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Authors: B. Yaman, G. Acikbas, N. Calis Acikbas

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Epoxy based materials have advantages in tribological applications due to their unique properties such as light weight, self-lubrication capacity and wear resistance. On the other hand, their usage is often limited by their low load bearing capacity and low thermal conductivity values. In this study, it is aimed to improve tribological and also mechanical properties of epoxy by reinforcing with ceramic based porcelain waste. It is well-known that the reuse or recycling of waste materials leads to reduction in production costs, ease of manufacturing, saving energy, etc. From this perspective, epoxy and epoxy matrix composites containing 60wt% porcelain waste with different particle size in the range of below 90µm and 150-250µm were fabricated, and the effect of filler particle size on the mechanical and tribological properties was investigated. The microstructural characterization was carried out by scanning electron microscopy (SEM), and phase analysis was determined by X-ray diffraction (XRD). The Archimedes principle was used to measure the density and porosity of the samples. The hardness values were measured using Shore-D hardness, and bending tests were performed. Microstructural investigations indicated that porcelain particles were homogeneously distributed and no agglomerations were encountered in the epoxy resin. Mechanical test results showed that the hardness and bending strength were increased with increasing particle size related to low porosity content and well embedding to the matrix. Tribological behavior of these composites was evaluated in terms of friction, wear rates and wear mechanisms by ball-on-disk contact with dry and rotational sliding at room temperature against WC ball with a diameter of 3mm. Wear tests were carried out at room temperature (23–25°C) with a humidity of 40 ± 5% under dry-sliding conditions. The contact radius of cycles was set to 5 mm at linear speed of 30 cm/s for the geometry used in this study. In all the experiments, 3N of constant test load was applied at a frequency of 8 Hz and prolonged to 400m wear distance. The friction coefficient of samples was recorded online by the variation in the tangential force. The steady-state CoFs were changed in between 0,29-0,32. The dimensions of the wear tracks (depth and width) were measured as two-dimensional profiles by a stylus profilometer. The wear volumes were calculated by integrating these 2D surface areas over the diameter. Specific wear rates were computed by dividing the wear volume by the applied load and sliding distance. According to the experimental results, the use of porcelain waste in the fabrication of epoxy resin composites can be suggested to be potential materials due to allowing improved mechanical and tribological properties and also providing reduction in production cost.

Keywords: epoxy composites, mechanical properties, porcelain waste, tribological properties

Procedia PDF Downloads 188

Authors: Ahmad Zamzam

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With the development of the economy in recent years, Saudi Arabia has been maintaining high economic growth. Therefore, its energy consumption has increased dramatically. This economic growth reflected on the expansion of high-rise tower's construction. Jeddah coastal strip (cornice) has many high-rise buildings planned to start next few years. These projects required a massive amount of electricity that was not planned to be supplied by the old infrastructure. This research studies the effect of the building envelope on its thermal performance. It follows a parametric simulation methodology using Ecotect software to analyze the effect of the building envelope design on its cooling energy load for an office high-rise building in Jeddah, Saudi Arabia, which includes building geometrical form, massing treatments, orientation and glazing type effect. The research describes an integrated passive design approach to reduce the cooling requirement for high-rise building through an improved building envelope design. The research used Ecotect to make four simulation studies; the first simulation compares the thermal performance of five high-rise buildings, presenting the basic shape of the plan. All the buildings have the same plan area and same floor height. The goal of this simulation is to find out the best shape for the thermal performance. The second simulation studies the effect of orientation on the thermal performance by rotating the same building model to find out the best and the worst angle for the building thermal performance. The third simulation studies the effect of the massing treatment on the total cooling load. It compared five models with different massing treatment, but with the same total built up area. The last simulation studied the effect of the glazing type by comparing the total cooling load of the same building using five different glass type and also studies the feasibility of using these glass types by studying the glass cost effect. The results indicate that using the circle shape as building plan could reduce the thermal cooling load by 40%. Also, using shading devices could reduce the cooling loads by 5%. The study states that using any of the massing grooving, recess or any treatment that could increase the outer exposed surface is not preferred and will decrease the building thermal performance. Also, the result shows that the best direction for glazing and openings from thermal performance viewpoint in Jeddah is the North direction while the worst direction is the East one. The best direction angle for openings - regarding the thermal performance in Jeddah- is 15 deg West and the worst is 250 deg West (110 deg East). Regarding the glass type effect, comparing to the double glass with air fill type as a reference case, the double glass with Air-Low-E will save 14% from the required amount of the thermal cooling load annually. Argon fill and triple glass will save 16% and 17% from the total thermal cooling load respectively, but for the glass cost purpose, using the Argon fill and triple glass is not feasible.

Keywords: passive cooling, reduce thermal load, Jeddah, building shape, energy

Procedia PDF Downloads 115

Authors: Christopher Hardly Joseph, Nicola Pelagalli, Davide Mencarelli, Luca Pierantoni

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In this contribution, we report the electromagnetic response of a split ring resonator (SRR) based magnetic metamaterial unit cell in free space nature by means of a full-wave electromagnetic simulation. The effective parameters of these designed structures have been analyzed. The structures have been specifically designed to work at high frequency considering the development of many microwave and lower mm-wave devices. In addition to that, the application of the designed metamaterial structures is also proposed, namely metamaterial loaded planar transmission lines, potentially useful to optimize size and quality factor of circuit components and radiating elements.

Keywords: CPW, Microwave Components, Negative Permeability, Split Ring Resonator (SRR)

Procedia PDF Downloads 165

Authors: Delphine Mukaneza, Lin Qiao, Wang Pengxin, Li Yan, Chen Yingyi

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Human activities on land use make the land-cover gradually change or transit. In this study, we examined the use of Landsat TM data to detect the land use change of Kigali between 1987 and 2009 using remote sensing techniques and analysis of data using ENVI and ArcGIS, a GIS software. Six different categories of land use were distinguished: bare soil, built up land, wetland, water, vegetation, and others. With remote sensing techniques, we analyzed land use data in 1987, 1999 and 2009, changed areas were found and a dynamic situation of land use in Kigali city was found during the 22 years studied. According to relevant Landsat data, the research focused on land use change in accordance with the role of remote sensing in the process of urbanization. The result of the work has shown the rapid increase of built up land between 1987 and 1999 and a big decrease of vegetation caused by the rebuild of the city after the 1994 genocide, while in the period of 1999 to 2009 there was a reduction in built up land and vegetation, after the authority of Kigali city established, a Master Plan where all constructions which were not in the range of the master Plan were destroyed. Rwanda's capital, Kigali City, through the expansion of the urban area, it is increasing the internal employment rate and attracts business investors and the service sector to improve their economy, which will increase the population growth and provide a better life. The overall planning of the city of Kigali considers the environment, land use, infrastructure, cultural and socio-economic factors, the economic development and population forecast, urban development, and constraints specification. To achieve the above purpose, the Government has set for the overall planning of city Kigali, different stages of the detailed description of the design, strategy and action plan that would guide Kigali planners and members of the public in the future to have more detailed regional plans and practical measures. Thus, land use change is significantly the performance of Kigali active human area, which plays an important role for the country to take certain decisions. Another area to take into account is the natural situation of Kigali city. Agriculture in the region does not occupy a dominant position, and with the population growth and socio-economic development, the construction area will gradually rise and speed up the process of urbanization. Thus, as a developing country, Rwanda's population continues to grow and there is low rate of utilization of land, where urbanization remains low. As mentioned earlier, the 1994 genocide massacres, population growth and urbanization processes, have been the factors driving the dramatic changes in land use. The focus on further research would be on analysis of Rwanda’s natural resources, social and economic factors that could be, the driving force of land use change.

Keywords: land use change, urbanization, Kigali City, Landsat

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Authors: Binyam Teferi

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Numerical and theoretical analysis of mixed convection flow of magneto- hydrodynamics micropolar fluid with stretching capillary in the presence of thermal radiation, chemical reaction, viscous dissipation, and heat generation/ absorption have been studied. The non-linear partial differential equations of momentum, angular velocity, energy, and concentration are converted into ordinary differential equations using similarity transformations which can be solved numerically. The dimensionless governing equations are solved by using Runge Kutta fourth and fifth order along with the shooting method. The effect of physical parameters viz., micropolar parameter, unsteadiness parameter, thermal buoyancy parameter, concentration buoyancy parameter, Hartmann number, spin gradient viscosity parameter, microinertial density parameter, thermal radiation parameter, Prandtl number, Eckert number, heat generation or absorption parameter, Schmidt number and chemical reaction parameter on flow variables viz., the velocity of the micropolar fluid, microrotation, temperature, and concentration has been analyzed and discussed graphically. MATLAB code is used to analyze numerical and theoretical facts. From the simulation study, it can be concluded that an increment of micropolar parameter, Hartmann number, unsteadiness parameter, thermal and concentration buoyancy parameter results in decrement of velocity flow of micropolar fluid; microrotation of micropolar fluid decreases with an increment of micropolar parameter, unsteadiness parameter, microinertial density parameter, and spin gradient viscosity parameter; temperature profile of micropolar fluid decreases with an increment of thermal radiation parameter, Prandtl number, micropolar parameter, unsteadiness parameter, heat absorption, and viscous dissipation parameter; concentration of micropolar fluid decreases as unsteadiness parameter, Schmidt number and chemical reaction parameter increases. Furthermore, computational values of local skin friction coefficient, local wall coupled coefficient, local Nusselt number, and local Sherwood number for different values of parameters have been investigated. In this paper, the following important results are obtained; An increment of micropolar parameter and Hartmann number results in a decrement of velocity flow of micropolar fluid. Microrotation decreases with an increment of the microinertial density parameter. Temperature decreases with an increasing value of the thermal radiation parameter and viscous dissipation parameter. Concentration decreases as the values of Schmidt number and chemical reaction parameter increases. The coefficient of local skin friction is enhanced with an increase in values of both the unsteadiness parameter and micropolar parameter. Increasing values of unsteadiness parameter and micropolar parameter results in an increment of the local couple stress. An increment of values of unsteadiness parameter and thermal radiation parameter results in an increment of the rate of heat transfer. As the values of Schmidt number and unsteadiness parameter increases, Sherwood number decreases.

Keywords: thermal radiation, chemical reaction, viscous dissipation, heat absorption/ generation, similarity transformation

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Authors: Allal Bedlaoui, Hamid Boutoutaou

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Due to its superior economics, shrink-fit assembly is one of the best mechanical assembly methods. There are simply two components, the axis and hub. It is used in many different industries, including the production of trains, cars, and airplanes. The outer radius of the inner cylinder must be greater than the inner radius of the outer cylinder for this operation; this difference is referred to as the "interference" between the two cylinders. There are three ways to accomplish this: heating the outer cylinder to cause it to expand; cooling the cylinder's inside to cause it to contract; and third, finishing the fitting under a press. At the intersection of the two matched parts, a contact pressure and friction force are generated. We consider interference and form defects in this article because they prevent the connection between the axis and the hub from having a perfect form surface and because we will be looking at how they affect the assembly. Numerical simulation is used to ascertain if interference and form defects have a beneficial or negative influence in the distribution of stresses, assembly resistance, and plasticity.

Keywords: shrink-fit, interference, form defect, plasticity, extraction force

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Authors: Toshiki Ito, Takahiro Yamane, Yuki Adachi, Yoshiko Kato, Eiji Tsuda, Kousaku Nagasaka, Keigo Yoshida, Yoshiko Kawasaki, Naoki Aizawa, Kyouhei Nishi, Tetsuko Kato

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The epidemic of the coronavirus (COVID-19), first reported in Wuhan at the end of 2019, has drastically changed our daily lives. Under these circumstances, counseling, which provides psychological support to people, was also greatly affected. The structure of counseling, which had generally been implicitly common practice to be conducted in person, was greatly shaken. The author wondered how counseling can be conducted in situations where it is impossible to meet face-to-face. This is where telepsychological support (online counseling) came into use. The authors found that there were the following problems in telepsychological support: (1) anxiety about whether the communication is appropriate, (2) difficulty in understanding the client's situation and condition, (3) inability to perceive what was normally perceived in person, (4) difficulty in adjusting to severely ill clients, (5) difficulty in dealing with emergency situations, etc. In this study, we interviewed psychologists who had been accustomed to telepsychological support for more than two years after the Corona disaster began to clarify how they had or had not overcome the problems of telepsychological support identified in the above studies. We also aim to consider the unique possibilities of how telepsychological support, a new technique of psychological support, can be implemented to provide more effective and meaningful support in society after the end of the Corona disaster (post-Corona society). Thirteen psychologists who are currently providing telepsychological support in the Corona Disaster will be interviewed, and semi-structured interviews will be conducted for one hour per person. In order to empirically examine how the problems in telepsychological support had been overcome or not through the interview survey, the authors asked (1) how they overcame their anxiety about whether they were able to communicate appropriately, (2) how they devised ways to overcome it, (3) how they overcame the difficulty in adapting to heavy clients in terms of the level of the disease, (4) how they overcame the difficulty in dealing with emergency situations. The interviews were analyzed using Thematic Analysis, a qualitative analysis method commonly used in qualitative research overseas. The authors found that some devices and perspectives were newly discovered as a result of two years of practice of telepsychological support and that psychologists in this study considered face-to-face interviews and telepsychological support to be separate and were flexible enough to use them when available and to move to face-to-face interviews when not appropriate.

Keywords: telepsychology, COVID-19, Corona, psychologist

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Authors: Ridvan Yamanoglu, Ismail Daoud

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In the current study, carbonyl nickel powders were sintered by uniaxial hot pressing technique. Loose starting powders were poured directly into a graphite die with a 15.4 mm inner diameter. Two graphite punches with an outer diameter of 15 mm were inserted into the die; then the powders were sintered at different sintering temperatures, holding times and pressure conditions. The sintered samples were polished and examined by optical microscopy. Hardness and bending behavior of the sintered samples were investigated in order to determine the mechanical properties of the sintered nickel samples. To carried out the friction properties of the produced samples wear tests were studied using a pin on disc tribometer. Load and distance were selected as wear test parameters. The fracture surface of the samples after bending test was also carried out by using scanning electron microscopy.

Keywords: nickel powder, sintering, hot press, mechanical properties

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Authors: Fuad Hamsyah

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Since last two decades, major disasters have happened in the Philippines and Indonesia as two countries that are located in the pacific ring of fire territory. While in Southeast Asian countries, the process of psychosocial support provision is facing various constraints such as limited number of mental health professionals and the limited knowledge about the provision of psychosocial support for disaster survivors. Yet after the tsunami disaster in 2004, many Asian countries begin to develop policies about the provision of psychosocial interventions as an effort for future disasters preparedness. In addition, mental health professionals have to consider the local cultural values and beliefs in order to provide people with effective psychosocial support since cultural values and beliefs play a significant role in the diversity of psychological distress that forms symptoms formation, and people’s way to seek for psychological assistance. This study is a critical literature review on 130 relevant selected documents and literatures. IASC MHPSS guideline is used as the research framework in doing critical analysis. The purpose of this study is to conduct a critical analysis on the mental health and psychosocial support provision in the Philippines and Indonesia with three main objectives: 1) To describe strengths, weaknesses, and challenges in the process of psychosocial supports given by public and private organizations in emergency settings of disaster in the Philippines and Indonesia, 2) To compare psychosocial support practices between the Philippines and Indonesia, and to identify the good practices among these countries, 3) To learn how cultural values influence the implementation of psychosocial supports in emergency settings of disaster. This research indicated that almost every function from IASC MHPSS guidelines has been implemented effectively in the Philippines and Indonesia, yet not in every detail of IASC MHPSS guidelines. Several similarities and differences are indicated in this study also based on the IASC MHPSS guidelines as the analysis framework. Further, both countries have some good practices that can be useful as an example of a comprehensive psychosocial support implementation. Apart from the IASC MHPSS guideline, cultural values and beliefs in the Philippines such as kanya-kanya syndrome, pakikipakapwa, utang na loob, bahala na, pagkaya are indicated as several cultural values that have strong influences towards people’s attitude and behavior in disaster situations. While in Indonesia, several cultural values such as sabar and nrimo become two important attitudes to cope disaster situations.

Keywords: disaster, Indonesia, psychosocial support, Philippines

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Authors: Abraham Finkelman

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Computerized Surgical Guides have been proven to be a predictable way to perform dental implants, with a relatively high accuracy in comparison to a treatment plan. When using the CSG Bone supported, it allows us to make the necessary changes of the hard tissue prior to the implant placement and after the implant placement. The CSG gives us an accurate position for the drilling, and during the implant placement it allows us to alter the vertical position of the implant altering the final position of the abutment and avoiding any risk of any damage to the adjacent anatomical structures. Any Changes required to the bone level can be done prior to the fixation of the CSG using a reduction guide, which incur extra surgical fees and the need of a second surgical guide. Any changes of the bone level after the implant placement are at the risk of damaging the implant neck surface. The technique consists of a universal system that allows us to remove the excess bone around the implant sockets prior to the implant placement which then enables us to place the implant in the vertical position with accuracy as planned with the CSG. The systems consist of a hollow pin of different sizes and diameters. Depending on the implant system that we are using. Length sizes are from 6mm-16mm and a diameter of 2.6mm-4.8mm. Upon the completion of the drilling, the pin is then inserted into the implant socket-using the insertion tool. Once the insertion tool has unscrewed the pin, we can continue with the bone reduction. The bone reduction can be done using conventional methods upon the removal of all the excess bone around the pin. The insertion tool is then screwed into the pin and the pin is then removed. We now, have the new bone level at the crest of the implant socket which is our mark for the vertical position of the implant. In some cases, when we are locating the implant very close to anatomical structures, any form of deviation to the vertical position of the implant during the surgery, can cause damage to such anatomical structures, creating irreversible damages such as paresthesia or dysesthesia of the mandibular nerve. If we are planning for immediate loading and we have done our temporary restauration in base of our computerized plan, deviation in the vertical position of the implant will affect the position of the abutment, affecting the accuracy of the temporary prosthesis, extending the working time till we adapt the prosthesis to the new position.

Keywords: bone reduction, computer aided navigation, dental implant placement, surgical guides

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Authors: Karim Adinehvand, Bakhtiar Azadbakht, Amin Sahebnasagh

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Relation to high absorption fraction of Tc SESTAMIBI by internal organs in heart scan, and these organs are near to generation organs (Ovaries and uterus). In this study, Liver is specified as source organ. Method: we have set amount of absorbed fraction radiopharmaceutical in position of Liver in RANDO-phantom in form of elliptical surfaces, then absorbed dose to ovaries and uterus measured by TLD-100 that had set at position of these organs in RANDO-phantom. Calculation had done by MIRD method. Results from direct measurement and MIRD method are too similar. The absorbed dose to uterus and ovaries for Rest are 26.05µGyMBq-1, 17.23µGyMBq-1 and for Stress are 2.04µGyMBq-1, 1.35µGyMBq-1 respectively.

Keywords: absorbed dose, TLD, MIRD, RANDO-phantom, Tc-99m

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Authors: Manish Kumar Thakur, Subrata Kumar Ghosh

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Various types of particles found in lubricant may be characterized by their fractal dimension. Some of the available methods are: yard-stick method or structured walk method, box-counting method. This paper presents a review of the developments and progress in fractal dimension computing methods as applied to characteristics the surface of wear particles. An overview of these methods, their implementation, their advantages and their limits is also present here. It has been accepted that wear particles contain major information about wear and friction of materials. Morphological analysis of wear particles from a lubricant is a very effective way for machine condition monitoring. Fractal dimension methods are used to characterize the morphology of the found particles. It is very useful in the analysis of complexity of irregular substance. The aim of this review is to bring together the fractal methods applicable for wear particles.

Keywords: fractal dimension, morphological analysis, wear, wear particles

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Authors: Rasouli Divkalaee Zeinab, Kalteh Safa, Roudbari Aliakbar

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Introduction: Medical waste can lead to the generation and transmission of many infectious and contagious diseases due to the presence of pathogenic agents, thereby necessitating the need for special management to collect, decontaminate, and finally dispose of such products. This study aimed to design a centralized health care (medical) waste management program for the cities of Semnan, Mahdishahr, and Shahmirzad. Methods: This descriptive-analytical study was conducted for six months in the cities of Semnan, Mahdishahr, and Shahmirzad. In this study, the quantitative and qualitative characteristics of the generated wastes were determined by taking samples from all medical waste production centers. Then, the equipment, devices, and machines required for separate collection of the waste from the production centers and for their subsequent decontamination were estimated. Next, the investment costs, current costs, and working capital required for collection, decontamination, and final disposal of the wastes were determined. Finally, the payment for proper waste management of each category of medical waste-producing centers was determined. Results: 1021 kilograms of medical waste are produced daily in the cities of Semnan, Mahdishahr, and Shahmirzad. It was estimated that a 1000-liter autoclave, a machine for collecting medical waste, four 60-liter bins, four 120-liter bins, and four 1200-liter bins were required for implementing the study plan. Also, the estimated total annual medical waste management costs for Semnan City were determined (23,283,903,720 Iranian Rials). Conclusion: The study results showed that establishing a proper management system for medical wastes generated in the three studied cities will cost between 334,280 and 1,253,715 Iranian Rials in fees for the medical centers. The findings of this study provided comprehensive data regarding medical wastes from the generation point to the landfill site, which is vital for the government and the private sector.

Keywords: clinics, decontamination, management, medical waste

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Authors: Keigo Nishitani, Kohei Mizuta Mizuta, Kazuyoshi Kurita, Yukinori Taniguchi

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To establish mass production process of Ti capsule which has Fe powder inside as magnetic hyperthermia implant, we assumed that Ti thin sheet can be drawn into a φ1.0 mm die hole through the medium of Fe Powder and becomes outer shell of capsule. This study discusses mechanism of powder assisted deep drawing process by both of numerical simulation and experiment. Ti thin sheet blank was placed on die, and was covered by Fe powder layer without pressurizing. Then upper punch was indented on the Fe powder layer, and the blank can be drawn into die cavity as pressurized powder particles were extruded into die cavity from behind of the drawn blank. Distinct Element Method (DEM) has been used to demonstrate the process. To identify bonding parameters on Fe particles which are cohesion, tensile bond stress and inter particle friction angle, axial and diametrical compression failure test of Fe powder compact was conducted. Several density ratios of powder compacts in range of 0.70 - 0.85 were investigated and relationship between mean stress and equivalent stress was calculated with consideration of critical state line which rules failure criterion in consolidation of Fe powder. Since variation of bonding parameters with density ratio has been experimentally identified, and good agreement has been recognized between several failure tests and its simulation, demonstration of powder assisted sheet forming by using DEM becomes applicable. Results of simulation indicated that indent/drawing length of Ti thin sheet is promoted by smaller Fe particle size, larger indent punch diameter, lower friction coefficient between die surface and Ti sheet and certain degrees of die inlet taper angle. In the deep drawing test, we have made die-set with φ2.4 mm punch and φ1.0 mm die bore diameter. Pure Ti sheet with 100 μm thickness, annealed at 650 deg. C has been tested. After indentation, indented/drawn capsule has been observed by microscope, and its length was measured to discuss the feasibility of this capsulation process. Longer drawing length exists on progressive loading pass comparing with the case of single stroke loading. It is expected that progressive loading has an advantage of which extrusion of powder particle into die cavity with Ti sheet is promoted since powder particle layer can be rebuilt while the punch is withdrawn from the layer in each loading steps. This capsulation phenomenon is qualitatively demonstrated by DEM simulation. Finally, we have fabricated Ti capsule which has Fe powder inside for magnetic hyperthermia cancer care treatment. It is concluded that suggested method is possible to use the manufacturing of Ti capsule implant for magnetic hyperthermia cancer care.

Keywords: metal powder compaction, metal forming, distinct element method, cancer care, magnetic hyperthermia

Procedia PDF Downloads 282

Authors: Anderson S. Fonseca, Italo F. S. Da Silva, Robert D. A. Santos, Mayara G. Da Silva, Pedro H. C. Vieira, Antonio M. S. Sobrinho, Victor H. B. Lemos, Petterson S. Diniz, Anselmo C. Paiva, Eliana M. G. Monteiro

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In Brazil, the National Electric Energy Agency (ANEEL) establishes that electrical energy companies are responsible for measuring and billing their customers. Among these regulations, it’s defined that a company must bill your customers within 27-33 days. If a relocation or a change of period is required, the consumer must be notified in writing, in advance of a billing period. To make it easier to organize a workday’s measurements, these companies create a reading plan. These plans consist of grouping customers into reading groups, which are visited by an employee responsible for measuring consumption and billing. The creation process of a plan efficiently and optimally is a capacitated clustering problem with constraints related to homogeneity and compactness, that is, the employee’s working load and the geographical position of the consuming unit. This process is a work done manually by several experts who have experience in the geographic formation of the region, which takes a large number of days to complete the final planning, and because it’s human activity, there is no guarantee of finding the best optimization for planning. In this paper, the GBKMeans method presents a technique based on K-Means and genetic algorithms for creating a capacitated cluster that respects the constraints established in an efficient and balanced manner, that minimizes the cost of relocating consumer units and the time required for final planning creation. The results obtained by the presented method are compared with the current planning of a real city, showing an improvement of 54.71% in the standard deviation of working load and 11.97% in the compactness of the groups.

Keywords: capacitated clustering, k-means, genetic algorithm, districting problems

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Authors: A. Mulry, C. Kealey, D. B. Brady

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Planktonic bacteria can form biofilms which are microbial aggregates embedded within a matrix of extracellular polymeric substances (EPS). They can be found attached to abiotic or biotic surfaces. Biofilms are responsible for oral diseases such as dental caries, gingivitis and the progression of periodontal disease. Biofilms can resist 500 to 1000 times the concentration of biocides and antibiotics used to kill planktonic bacteria. Biofilm development on oral surfaces involves four stages, initial attachment, early development, maturation and dispersal of planktonic cells. The Minimum Inhibitory Concentration (MIC) was determined using a range of saturated and unsaturated fatty acids using the resazurin assay, followed by serial dilution and spot plating on BHI agar plates to establish the Minimum Bactericidal Concentration (MBC). Log reduction of bacteria was also evaluated for each fatty acid. The Minimum Biofilm Inhibition Concentration (MBIC) was determined using crystal violet assay in 96 well plates on forming and pre-formed S. mutans biofilms using BHI supplemented with 1% sucrose. Saturated medium-chain fatty acids Octanoic (C8.0), Decanoic (C10.0) and Undecanoic acid (C11.0) do not display strong antibiofilm properties; however, Lauric (C12.0) and Myristic (C14.0) display moderate antibiofilm properties with 97.83% and 97.5% biofilm inhibition with 1000 µM respectively. Monounsaturated, Oleic acid (C18.1) and polyunsaturated large chain fatty acids, Linoleic acid (C18.2) display potent antibiofilm properties with biofilm inhibition of 99.73% at 125 µM and 100% at 65.5 µM, respectively. Long-chain polyunsaturated Omega-3 fatty acids α-Linoleic (C18.3), Eicosapentaenoic Acid (EPA) (C20.5), Docosahexaenoic Acid (DHA) (C22.6) have displayed strong antibiofilm efficacy from concentrations ranging from 31.25-250µg/ml. DHA is the most promising antibiofilm agent with an MBIC of 99.73% with 15.625µg/ml. This may be due to the presence of six double bonds and the structural orientation of the fatty acid. To conclude, fatty acids displaying the most antimicrobial activity appear to be medium or long-chain unsaturated fatty acids containing one or more double bonds. Most promising agents include Omega-3-fatty acids Linoleic, α-Linoleic, EPA and DHA, as well as Omega-9 fatty acid Oleic acid. These results indicate that fatty acids have the potential to be used as antimicrobials and antibiofilm agents against S. mutans. Future work involves further screening of the most potent fatty acids against a range of bacteria, including Gram-positive and Gram-negative oral pathogens. Future work will involve incorporating the most effective fatty acids onto dental implant devices to prevent biofilm formation.

Keywords: antibiofilm, biofilm, fatty acids, S. mutans

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