Search results for: single unit heavy vehicle
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9277

Search results for: single unit heavy vehicle

2587 Learning Physics Concepts through Language Syntagmatic Paradigmatic Relations

Authors: C. E. Laburu, M. A. Barros, A. F. Zompero, O. H. M. Silva

Abstract:

The work presents a teaching strategy that employs syntagmatic and paradigmatic linguistic relations in order to monitor the understanding of physics students’ concepts. Syntagmatic and paradigmatic relations are theoretical elements of semiotics studies and our research circumstances and justified them within the research program of multi-modal representations. Among the multi-modal representations to learning scientific knowledge, the scope of action of syntagmatic and paradigmatic relations belongs to the discursive writing form. The use of such relations has the purpose to seek innovate didactic work with discourse representation in the write form before translate to another different representational form. The research was conducted with a sample of first year high school students. The students were asked to produce syntagmatic and paradigmatic of Newton’ first law statement. This statement was delivered in paper for each student that should individually write the relations. The student’s records were collected for analysis. It was possible observed in one student used here as example that their monemes replaced and rearrangements produced by, respectively, syntagmatic and paradigmatic relations, kept the original meaning of the law. In paradigmatic production he specified relevant significant units of the linguistic signs, the monemas, which constitute the first articulation and each word substituted kept equivalence to the original meaning of original monema. Also, it was noted a number of diverse and many monemas were chosen, with balanced combination of grammatical (grammatical monema is what changes the meaning of a word, in certain positions of the syntagma, along with a relatively small number of other monemes. It is the smallest linguistic unit that has grammatical meaning) and lexical (lexical monema is what belongs to unlimited inventories; is the monema endowed with lexical meaning) monemas. In syntagmatic production, monemas ordinations were syntactically coherent, being linked with semantic conservation and preserved number. In general, the results showed that the written representation mode based on linguistic relations paradigmatic and syntagmatic qualifies itself to be used in the classroom as a potential identifier and accompanist of meanings acquired from students in the process of scientific inquiry.

Keywords: semiotics, language, high school, physics teaching

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2586 Sustainable Hydrogen Generation via Gasification of Pig Hair Biowaste with NiO/Al₂O₃ Catalysts

Authors: Jamshid Hussain, Kuen Song Lin

Abstract:

Over one thousand tons of pig hair biowaste (PHB) are produced yearly in Taiwan. The improper disposal of PHB can have a negative impact on the environment, consequently contributing to the spread of diseases. The treatment of PHB has become a major environmental and economic challenge. Innovative treatments must be developed because of the heavy metal and sulfur content of PHB. Like most organic materials, PHB is composed of many organic volatiles that contain large amounts of hydrogen. Hydrogen gas can be effectively produced by the catalytic gasification of PHB using a laboratory-scale fixed-bed gasifier, employing 15 wt% NiO/Al₂O₃ catalyst at 753–913 K. The derived kinetic parameters were obtained and refined using simulation calculations. FE–SEM microphotograph showed that NiO/Al₂O₃ catalyst particles are Spherical or irregularly shaped with diameters of 10–20 nm. HR–TEM represented that the fresh Ni particles were evenly dispersed and uniform in the microstructure of Al₂O₃ support. The sizes of the NiO nanoparticles were vital in determining catalyst activity. As displayed in the pre-edge XANES spectra of the NiO/Al₂O₃ catalysts, it exhibited a non-intensive absorbance nature for the 1s to 3d transition, which is prohibited by the selection rule for an ideal octahedral symmetry. Similarly, the populace of Ni(II) and Ni(0) onto Al₂O₃ supports are proportional to the strength of the 1s to 4pxy transition, respectively. The weak shoulder at 8329–8334 eV and a strong character at 8345–8353 eV were ascribed to the 1s to 4pxy shift, which suggested the presence of NiO types onto Al₂O₃ support in PHB catalytic gasification. As determined by the XANES analyses, Ni(II)→Ni(0) reduction was mostly observed. The oxidation of PHB onto the NiO/Al₂O₃ surface may have resulted in Ni(0) and the formation of tar during the gasification process. The EXAFS spectra revealed that the Ni atoms with Ni–Ni/Ni–O bonds were found. The Ni–O bonding proved that the produced syngas were unable to reduce NiO to Ni(0) completely. The weakness of the Ni–Ni bonds may have been caused by the highly dispersed Ni in the Al₂O₃ support. The central Ni atoms have Ni–O (2.01 Å) and Ni–Ni (2.34 Å) bond distances in the fresh NiO/Al₂O₃ catalyst. The PHB was converted into hydrogen-rich syngas (CO + H₂, >89.8% dry basis). When PHB (250 kg h−1) was catalytically gasified at 753–913 K, syngas was produced at approximately 5.45 × 105 kcal h−1 of heat recovery with 76.5%–83.5% cold gas efficiency. The simulation of the pilot-scale PHB catalytic gasification demonstrated that the system could provide hydrogen (purity > 99.99%) and generate electricity for an internal combustion engine of 100 kW and a proton exchange membrane fuel cell (PEMFC) of 175 kW. A projected payback for a PHB catalytic gasification plant with a capacity of 10- or 20-TPD (ton per day) was around 3.2 or 2.5 years, respectively.

Keywords: pig hair biowaste, catalytic gasification, hydrogen production, PEMFC, resource recovery

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2585 A Review on the Future Canadian RADARSAT Constellation Mission and Its Capabilities

Authors: Mohammed Dabboor

Abstract:

Spaceborne Synthetic Aperture Radar (SAR) systems are active remote sensing systems independent of weather and sun illumination, two factors which usually inhibit the use of optical satellite imagery. A SAR system could acquire single, dual, compact or fully polarized SAR imagery. Each SAR imagery type has its advantages and disadvantages. The sensitivity of SAR images is a function of the: 1) band, polarization, and incidence angle of the transmitted electromagnetic signal, and 2) geometric and dielectric properties of the radar target. The RADARSAT-1 (launched on November 4, 1995), RADARSAT-2 ((launched on December 14, 2007) and RADARSAT Constellation Mission (to be launched in July 2018) are three past, current, and future Canadian SAR space missions. Canada is developing the RADARSAT Constellation Mission (RCM) using small satellites to further maximize the capability to carry out round-the-clock surveillance from space. The Canadian Space Agency, in collaboration with other government-of-Canada departments, is leading the design, development and operation of the RADARSAT Constellation Mission to help addressing key priorities. The purpose of our presentation is to give an overview of the future Canadian RCM SAR mission with its satellites. Also, the RCM SAR imaging modes along with the expected SAR products will be described. An emphasis will be given to the mission unique capabilities and characteristics, such as the new compact polarimetry SAR configuration. In this presentation, we will summarize the RCM advancement from previous RADARSAT satellite missions. Furthermore, the potential of the RCM mission for different Earth observation applications will be outlined.

Keywords: compact polarimetry, RADARSAT, SAR mission, SAR applications

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2584 The Influence of Hydrogen Addition to Natural Gas Networks on Gas Appliances

Authors: Yitong Xie, Chaokui Qin, Zhiguang Chen, Shuangqian Guo

Abstract:

Injecting hydrogen, a competitive carbon-free energy carrier, into existing natural gas networks has become a promising step toward alleviating global warming. Considering the differences in properties of hydrogen and natural gas, there is very little evidence showing how many degrees of hydrogen admixture can be accepted and how to adjust appliances to adapt to gas constituents' variation. The lack of this type of analysis provides more uncertainty in injecting hydrogen into networks because of the short the basis of burner design and adjustment. First, the properties of methane and hydrogen were compared for a comprehensive analysis of the impact of hydrogen addition to methane. As the main determinant of flame stability, the burning velocity was adopted for hydrogen addition analysis. Burning velocities for hydrogen-enriched natural gas with different hydrogen percentages and equivalence ratios were calculated by the software CHEMKIN. Interchangeability methods, including single index methods, multi indices methods, and diagram methods, were adopted to determine the limit of hydrogen percentage. Cooktops and water heaters were experimentally tested in the laboratory. Flame structures of different hydrogen percentages and equivalence ratios were observed and photographed. Besides, the change in heat efficiency, burner temperature, emission by hydrogen percentage, and equivalence ratio was studied. The experiment methodologies and results in this paper provide an important basis for the introduction of hydrogen into gas pipelines and the adjustment of gas appliances.

Keywords: hydrogen, methane, combustion, appliances, interchangeability

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2583 Technologic Information about Photovoltaic Applied in Urban Residences

Authors: Stephanie Fabris Russo, Daiane Costa Guimarães, Jonas Pedro Fabris, Maria Emilia Camargo, Suzana Leitão Russo, José Augusto Andrade Filho

Abstract:

Among renewable energy sources, solar energy is the one that has stood out. Solar radiation can be used as a thermal energy source and can also be converted into electricity by means of effects on certain materials, such as thermoelectric and photovoltaic panels. These panels are often used to generate energy in homes, buildings, arenas, etc., and have low pollution emissions. Thus, a technological prospecting was performed to find patents related to the use of photovoltaic plates in urban residences. The patent search was based on ESPACENET, associating the keywords photovoltaic and home, where we found 136 patent documents in the period of 1994-2015 in the fields title and abstract. Note that the years 2009, 2010, 2011, 2012, 2013 and 2014 had the highest number of applicants, with respectively, 11, 13, 23, 29, 15 and 21. Regarding the country that deposited about this technology, it is clear that China leads with 67 patent deposits, followed by Japan with 38 patents applications. It is important to note that most depositors, 50% are companies, 44% are individual inventors and only 6% are universities. On the International Patent classification (IPC) codes, we noted that the most present classification in results was H02J3/38, which represents provisions in parallel to feed a single network by two or more generators, converters or transformers. Among all categories, there is the H session, which means Electricity, with 70% of the patents.

Keywords: photovoltaic, urban residences, technology forecasting, prospecting

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2582 Antiulcer Potential of Heme Oxygenase-1 Inducers

Authors: Gaweł Magdalena, Lipkowska Anna, Olbert Magdalena, Frąckiewicz Ewelina, Librowski Tadeusz, Nowak Gabriel, Pilc Andrzej

Abstract:

Heme oxygenase-1 (HO-1), also known as heat shock protein 32 (HSP32), has been shown to be implicated in cytoprotection in various organs. Its activation plays a significant role in acute and chronic inflammation, protecting cells from oxidative injury and apoptosis. This inducible isoform of HO catalyzes the first and rate-limiting step in heme degradation to produce equimolar quantities of biologically active products: carbon monoxide (CO), free iron and biliverdin. CO has been reported to possess anti-apoptotic properties. Moreover, it inhibits the production of proinflammatory cytokines and stimulates the synthesis of the anti-inflammatory interleukin-10 (IL-10), as well as promotes vasodilatation at sites of inflammation. The second product of catalytic HO-1 activity, free cytotoxic iron, is promptly sequestered into the iron storage protein ferritin, which lowers the pro-oxidant state of the cell. The third product, biliverdin, is subsequently converted by biliverdin reductase into the bile pigment bilirubin, the most potent endogenous antioxidant among the constituents of human serum, which modulates immune effector functions and suppresses inflammatory response. Furthermore, being one of the so-called stress proteins, HO-1 adaptively responds to different stressors, such as reactive oxygen species (ROS), inflammatory cytokines and heavy metals and thus protects cells against such conditions as ischemia, hemorrhagic shock, heat shock or hypoxia. It is suggested that pharmacologic modulation of HO-1 may represent an effective strategy for prevention of stress and drug-induced gastrointestinal toxicity. HO-1 is constitutively expressed in normal gastric, intestinal and colonic mucosa and up-regulated during inflammation. It has been proven that HO-1 up-regulated by hemin, heme and cobalt-protoporphyrin ameliorates experimental colitis. In addition, the up-regulation of HO-1 partially explains the mechanism of action of 5-aminosalicylic acid (5-ASA), which is used clinically as an anti-colitis agent. In 2009 Ueda et al. has reported for the first time that mucosal protection by Polaprezinc, a chelate compound of zinc and L-carnosine used as an anti-ulcer drug in Japan, is also attributed to induction of HO-1 in the stomach. Since then, inducers of HO-1 are desired subject of research, as they may constitute therapeutically effective anti-ulcer drugs.

Keywords: heme oxygenase-1, gastric lesions, gastroprotection, Polaprezinc

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2581 Blast Load Resistance of Bridge Columns

Authors: Amir Kavousifard, Lan Lin

Abstract:

The objective of this study is to evaluate the effects of the detailing in the seismic design of reinforced concrete (RC) bridge columns on the blast load resistance. A generic two-span continuous RC bridge located in Victoria, British Columbia, which represents the highest seismicity in Canada, was examined in the study. The bridge superstructure consists of a single cell box girder while the substructure consists of two circular columns. The bridge was designed according to the 2006 Canadian Highway Bridge Design Code. More specifically, response spectrum analysis was performed to determine the seismic demands using CSI Bridge. The 3D blast load analysis is carried out in the platform of LS-DYNA. Two charge heights, i.e., one at the mid-height of the column and the other at the bottom of the column, are considered. For each height, three cases are analyzed in order to investigate the effects of standoff and charge weight on the structural response. The blast load resistance of the column is assessed in terms of the concrete failure mechanism, steel stress distribution, and column lateral displacement. The results from the study indicate that a column designed in accordance with the code requirements could survive during the blast attack. Spiral columns perform much better than tied columns. The results also show that the charge weight has more impact on the structural response than the standoff. These results are beneficial for the development of the Canadian standards for the design of bridges under blast loads.

Keywords: blast, bridge, charge, height, seismic, standoff

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2580 Comparison between Deterministic and Probabilistic Stability Analysis, Featuring Consequent Risk Assessment

Authors: Isabela Moreira Queiroz

Abstract:

Slope stability analyses are largely carried out by deterministic methods and evaluated through a single security factor. Although it is known that the geotechnical parameters can present great dispersal, such analyses are considered fixed and known. The probabilistic methods, in turn, incorporate the variability of input key parameters (random variables), resulting in a range of values of safety factors, thus enabling the determination of the probability of failure, which is an essential parameter in the calculation of the risk (probability multiplied by the consequence of the event). Among the probabilistic methods, there are three frequently used methods in geotechnical society: FOSM (First-Order, Second-Moment), Rosenblueth (Point Estimates) and Monte Carlo. This paper presents a comparison between the results from deterministic and probabilistic analyses (FOSM method, Monte Carlo and Rosenblueth) applied to a hypothetical slope. The end was held to evaluate the behavior of the slope and consequent risk analysis, which is used to calculate the risk and analyze their mitigation and control solutions. It can be observed that the results obtained by the three probabilistic methods were quite close. It should be noticed that the calculation of the risk makes it possible to list the priority to the implementation of mitigation measures. Therefore, it is recommended to do a good assessment of the geological-geotechnical model incorporating the uncertainty in viability, design, construction, operation and closure by means of risk management. 

Keywords: probabilistic methods, risk assessment, risk management, slope stability

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2579 Quantitative Analysis of Three Sustainability Pillars for Water Tradeoff Projects in Amazon

Authors: Taha Anjamrooz, Sareh Rajabi, Hasan Mahmmud, Ghassan Abulebdeh

Abstract:

Water availability, as well as water demand, are not uniformly distributed in time and space. Numerous extra-large water diversion projects are launched in Amazon to alleviate water scarcities. This research utilizes statistical analysis to examine the temporal and spatial features of 40 extra-large water diversion projects in Amazon. Using a network analysis method, the correlation between seven major basins is measured, while the impact analysis method is employed to explore the associated economic, environmental, and social impacts. The study unearths that the development of water diversion in Amazon has witnessed four stages, from a preliminary or initial period to a phase of rapid development. It is observed that the length of water diversion channels and the quantity of water transferred have amplified significantly in the past five decades. As of 2015, in Amazon, more than 75 billion m³ of water was transferred amidst 12,000 km long channels. These projects extend over half of the Amazon Area. The River Basin E is currently the most significant source of transferred water. Through inter-basin water diversions, Amazon gains the opportunity to enhance the Gross Domestic Product (GDP) by 5%. Nevertheless, the construction costs exceed 70 billion US dollars, which is higher than any other country. The average cost of transferred water per unit has amplified with time and scale but reduced from western to eastern Amazon. Additionally, annual total energy consumption for pumping exceeded 40 billion kilowatt-hours, while the associated greenhouse gas emissions are assessed to be 35 million tons. Noteworthy to comprehend that ecological problems initiated by water diversion influence the River Basin B and River Basin D. Due to water diversion, more than 350 thousand individuals have been relocated, away from their homes. In order to enhance water diversion sustainability, four categories of innovative measures are provided for decision-makers: development of water tradeoff projects strategies, improvement of integrated water resource management, the formation of water-saving inducements, and pricing approach, and application of ex-post assessment.

Keywords: sustainability, water trade-off projects, environment, Amazon

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2578 Experimental Investigation of the Effect of Compression Ratio in a Direct Injection Diesel Engine Running on Different Blends of Rice Bran Oil and Ethanol

Authors: Perminderjit Singh, Randeep Singh

Abstract:

The performance, emission and combustion characteristics of a single cylinder four stroke variable compression ratio multifuel engine when fueled with different blends of rice bran oil methyl ester and ethanol are investigated and compared with the results of standard diesel. Biodiesel produced from rice bran oil by transesterification process has been used in this study. The experiment has been conducted at a fixed engine speed of 1500 rpm, 50% load and at compression ratios of 16.5:1, 17:1, 17.5:1 and 18:1. The impact of compression ratio on fuel consumption, brake thermal efficiency and exhaust gas emissions has been investigated and presented. Optimum compression ratio which gives the best performance has been identified. The results indicate longer ignition delay, the maximum rate of pressure rise, lower heat release rate and higher mass fraction burnt at higher compression ratio for waste cooking oil methyl ester when compared to that of diesel. The brake thermal efficiency at 50% load for rice bran oil methyl ester blends and diesel has been calculated and the blend B40 is found to give maximum thermal efficiency. The blends when used as fuel results in the reduction of carbon monoxide, hydrocarbon and increase in nitrogen oxides emissions.

Keywords: biodiesel, rice bran oil, transesterification, ethanol, compression ratio

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2577 Monitoring Potential Temblor Localities as a Supplemental Risk Control System

Authors: Mikhail Zimin, Svetlana Zimina, Maxim Zimin

Abstract:

Without question, the basic method of prevention of human and material losses is the provision for adequate strength of constructions. At the same time, seismic load has a stochastic character. So, at all times, there is little danger of earthquake forces exceeding the selected design load. This risk is very low, but the consequences of such events may be extremely serious. Very dangerous are also occasional mistakes in seismic zoning, soil conditions changing before temblors, and failure to take into account hazardous natural phenomena caused by earthquakes. Besides, it is known that temblors detrimentally affect the environmental situation in regions where they occur, resulting in panic and worsening various disease courses. It may lead to mistakes of personnel of hazardous production facilities like the production and distribution of gas and oil, which may provoke severe accidents. In addition, gas and oil pipelines often have long mileage and cross many perilous zones by contrast with buildings. This situation increases the risk of heavy accidents. In such cases, complex monitoring of potential earthquake localities would be relevant. Even though the number of successful real-time forecasts of earthquakes is not great, it is well in excess, such as may be under random guessing. Experimental performed time-lapse study and analysis consist of searching seismic, biological, meteorological, and light earthquake precursors, processing such data with the help of fuzzy sets, collecting weather information, utilizing a database of terrain, and computing risk of slope processes under the temblor in a given setting. Works were done in a real-time environment and broadly acceptable results took place. Observations from already in-place seismic recording systems are used. Furthermore, a look back study of precursors of known earthquakes is done. Situations before Ashkhabad, Tashkent, and Haicheng seismic events are analyzed. Fairish findings are obtained. Results of earthquake forecasts can be used for predicting dangerous natural phenomena caused by temblors such as avalanches and mudslides. They may also be utilized for prophylaxis of some diseases and their complications. Relevant software is worked out too. It should be emphasized that such control does not require serious financial expenses and can be performed by a small group of professionals. Thus, complex monitoring of potential earthquake localities, including short-term earthquake forecasts and analysis of possible hazardous consequences of temblors, may further the safety of pipeline facilities.

Keywords: risk, earthquake, monitoring, forecast, precursor

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2576 Intelligent Chemistry Approach to Improvement of Oxygenates Analytical Method in Light Hydrocarbon by Multidimensional Gas Chromatography - FID and MS

Authors: Ahmed Aboforn

Abstract:

Butene-1 product is consider effectively raw material in Polyethylene production, however Oxygenates impurities existing will be effected ethylene/butene-1 copolymers synthesized through titanium-magnesium-supported Ziegler-Natta catalysts. Laterally, Petrochemical industries are challenge against poor quality of Butene-1 and other C4 mix – feedstock that reflected on business impact and production losing. In addition, propylene product suffering from contamination by oxygenates components and causing for lose production and plant upset of Polypropylene process plants. However, Multidimensional gas chromatography (MDGC) innovative analytical methodology is a chromatography technique used to separate complex samples, as mixing different functional group as Hydrocarbon and oxygenates compounds and have similar retention factors, by running the eluent through two or more columns instead of the customary single column. This analytical study striving to enhance the quality of Oxygenates analytical method, as monitoring the concentration of oxygenates with accurate and precise analytical method by utilizing multidimensional GC supported by Backflush technique and Flame Ionization Detector, which have high performance separation of hydrocarbon and Oxygenates; also improving the minimum detection limits (MDL) to detect the concentration <1.0 ppm. However different types of oxygenates as (Alcohols, Aldehyde, Ketones, Ester and Ether) may be determined in other Hydrocarbon streams asC3, C4-mix, until C12 mixture, supported by liquid injection auto-sampler.

Keywords: analytical chemistry, gas chromatography, petrochemicals, oxygenates

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2575 Territorial Analysis of the Public Transport Supply: Case Study of Recife City

Authors: Cláudia Alcoforado, Anabela Ribeiro

Abstract:

This paper is part of an ongoing PhD thesis. It seeks to develop a model to identify the spatial failures of the public transportation supply. In the construction of the model, it also seeks to detect the social needs arising from the disadvantage in transport. The case study is carried out for the Brazilian city of Recife. Currently, Recife has a population density of 7,039.64 inhabitants per km². Unfortunately, only 46.9% of urban households on public roads have adequate urbanization. Allied to this reality, the trend of the occupation of the poorest population is that of the peripheries, a fact that has been consolidated in Brazil and Latin America, thus burdening the families' income, since the greater the distances covered for the basic activities and consequently also the transport costs. In this way, there have been great impacts caused by the supply of public transportation to locations with low demand or lack of urban infrastructure. The model under construction uses methods such as Currie’s Gap Assessment associated with the London’s Public Transport Access Level, and the Public Transport Accessibility Index developed by Saghapour. It is intended to present the stage of the thesis with the spatial/need gaps of the neighborhoods of Recife already detected. The benefits of the geographic information system are used in this paper. It should be noted that gaps are determined from the transport supply indices. In this case, considering the presence of walking catchment areas. Still in relation to the detection of gaps, the relevant demand index is also determined. This, in turn, is calculated through indicators that reflect social needs. With the use of the smaller Brazilian geographical unit, the census sector, the model with the inclusion of population density in the study areas should present more consolidated results. Based on the results achieved, an analysis of transportation disadvantage will be carried out as a factor of social exclusion in the study area. It is anticipated that the results obtained up to the present moment, already indicate a strong trend of public transportation in areas of higher income classes, leading to the understanding that the most disadvantaged population migrates to those neighborhoods in search of employment.

Keywords: gap assessment, public transport supply, social exclusion, spatial gaps

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2574 An Ensemble Learning Method for Applying Particle Swarm Optimization Algorithms to Systems Engineering Problems

Authors: Ken Hampshire, Thomas Mazzuchi, Shahram Sarkani

Abstract:

As a subset of metaheuristics, nature-inspired optimization algorithms such as particle swarm optimization (PSO) have shown promise both in solving intractable problems and in their extensibility to novel problem formulations due to their general approach requiring few assumptions. Unfortunately, single instantiations of algorithms require detailed tuning of parameters and cannot be proven to be best suited to a particular illustrative problem on account of the “no free lunch” (NFL) theorem. Using these algorithms in real-world problems requires exquisite knowledge of the many techniques and is not conducive to reconciling the various approaches to given classes of problems. This research aims to present a unified view of PSO-based approaches from the perspective of relevant systems engineering problems, with the express purpose of then eliciting the best solution for any problem formulation in an ensemble learning bucket of models approach. The central hypothesis of the research is that extending the PSO algorithms found in the literature to real-world optimization problems requires a general ensemble-based method for all problem formulations but a specific implementation and solution for any instance. The main results are a problem-based literature survey and a general method to find more globally optimal solutions for any systems engineering optimization problem.

Keywords: particle swarm optimization, nature-inspired optimization, metaheuristics, systems engineering, ensemble learning

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2573 Is HR in a State of Transition? An International Comparative Study on the Development of HR Competencies

Authors: Barbara Covarrubias Venegas, Sabine Groblschegg, Bernhard Klaus, Julia Domnanovich

Abstract:

Research Objectives: The roles and activities of human resource management (HRM) have changed a lot in the past years. Driven by a changing environment and therefore, new business requirements, the scope of human resource (HR) activities has widened. The extent to which these activities should focus on strategic issues to support the long-term success of a company has been discussed in science for many years. As many economies of Central and Eastern Europe (CEE) experienced a phase of transition after the socialist era and are now recovering from the 2008 global crisis it is needed to examine the current state of HR positioning. Furthermore, a trend in HR work developing from rather administrative units to being strategic partners of management can be noticed. This leads to the question of better understanding the underlying competencies which are necessary to support organisations. This topic was addressed by the international study “HR Competencies in international comparison”. The quantitative survey was conducted by the Institute for Human Resources & Organisation of FHWien University of Applied Science of WKW (A) in cooperation with partner universities in the countries Bosnia-Herzegovina, Croatia, Serbia and Slovenia. Methodology: Using the questionnaire developed by Dave Ulrich we tested whether the HR Competency model can be used for Austria, Bosnia and Herzegovina, Croatia, Serbia and Slovenia. After performing confirmatory and exploratory factor analysis for the whole data set containing all five countries we could clearly distinguish between four competencies. In a further step, our analysis focused on median and average comparisons between the HR competency dimensions. Conclusion: Our literature review, in alignment with other studies, shows a relatively rapid pace of development of HR Roles and HR Competencies in BCSS in the past decades. Comparing data from BCSS and Austria we still can notice that regards strategic orientation there is a lack in BCSS countries, thus competencies are not as developed as in Austria. This leads us to the tentative conclusion that HR has undergone a rapid change but is still in a State of Transition from being a rather administrative unit to performing the role of a strategic partner.

Keywords: comparative study, HR competencies, HRM, HR roles

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2572 Investigation of Night Cooling Event, Experimental Radiator

Authors: Fatemeh Karampour

Abstract:

In the hot climate countries, especially those countries with great desert area, such as Iran, a considerable part of the energy is consumed due to cooling and air conditioning system in a hot season. So it is important to find a renewable energy supply for cooling systems. Although, there are few consistent researches in this field of renewable energy in compare with other fields. This research is presenting a study on performance of a night cooling radiator and working fluid storage for night time operation and day time resting periods. In these experiments, we didn’t expose any heating load but focused only on the possibility of system combination and its potential cooling effect. A very simple radiator has been designed in south of Iran, Shiraz, in order to perform this study. The radiator has been insulated with polystyrene foam and bubbled plastic sheets have been used as top cover. Using a single bubbled plastic sheet, the radiator temperature reached 0°C which is 20°C lower than minimum ambient temperature. Putting a small storage tank in the line increased the radiator’s minimum temperature at night; however, provided some cool fluid source for hot days of Shiraz that easily reaches 40°C. The results have shown very good cooling potential without heating load and acceptable temperature increasing during hot day with a small, short term storage tank. Future studies can make the system more effective and applicable.

Keywords: night cooling, experimental set up, cooling radiator, chill storage

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2571 Research of Stalled Operational Modes of Axial-Flow Compressor for Diagnostics of Pre-Surge State

Authors: F. Mohammadsadeghi

Abstract:

Relevance of research: Axial compressors are used in both aircraft engine construction and ground-based gas turbine engines. The compressor is considered to be one of the main gas turbine engine units, which define absolute and relative indicators of engine in general. Failure of compressor often leads to drastic consequences. Therefore, safe (stable) operation must be maintained when using axial compressor. Currently, we can observe a tendency of increase of power unit, productivity, circumferential velocity and compression ratio of axial compressors in gas turbine engines of aircraft and ground-based application whereas metal consumption of their structure tends to fall. This causes the increase of dynamic loads as well as danger of damage of high load compressor or engine structure elements in general due to transient processes. In operating practices of aeronautical engineering and ground units with gas turbine drive the operational stability failure of gas turbine engines is one of relatively often failure causes what can lead to emergency situations. Surge occurrence is considered to be an absolute buckling failure. This is one of the most dangerous and often occurring types of instability. However detailed were the researches of this phenomenon the development of measures for surge before-the-fact prevention is still relevant. This is why the research of transient processes for axial compressors is necessary in order to provide efficient, stable and secure operation. The paper addresses the problem of automatic control system improvement by integrating the anti-surge algorithms for axial compressor of aircraft gas turbine engine. Paper considers dynamic exhaustion of gas dynamic stability of compressor stage, results of numerical simulation of airflow flowing through the airfoil at design and stalling modes, experimental researches to form the criteria that identify the compressor state at pre-surge mode detection. Authors formulated basic ways for developing surge preventing systems, i.e. forming the algorithms that allow detecting the surge origination and the systems that implement the proposed algorithms.

Keywords: axial compressor, rotation stall, Surg, unstable operation of gas turbine engine

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2570 Influence of Loading Pattern and Shaft Rigidity on Laterally Loaded Helical Piles in Cohesion-Less Soil

Authors: Mohamed Hesham Hamdy Abdelmohsen, Ahmed Shawky Abdul Aziz, Mona Fawzy Al-Daghma

Abstract:

Helical piles are widely used as axially and laterally loaded deep foundations. Once they are required to resist bearing combined loads (BCLs), as axial compression and lateral thrust, different behaviour is expected, necessitating further investigation. The objective of the present article is to clarify the behaviour of a single helical pile of different shaft rigidity embedded in cohesion-less soil and subjected to simultaneous or successive loading patterns of BCLs. The study was first developed analytically and extended numerically. The numerical analysis was further verified through a laboratory experimental program on a set of helical pile models. The results indicate highly interactive effects of the studied parameters, but it is obviously confirmed that the pile performance increases with both the increase of shaft rigidity and the change of BCLs loading pattern from simultaneous to successive. However, it is noted that the increase of vertical load does not always enhance the lateral capacity but may cause a decrement in lateral capacity, as observed with helical piles of flexible shafts. This study provides insightful information for the design of helical piles in structures loaded by complex sequence of forces, wind turbines, and industrial shafts.

Keywords: helical pile, lateral loads, combined loads, cohesion-less soil, analytical, numerical

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2569 3D Hybrid Multiphysics Lattice Boltzmann Model for Studying the Flow Behavior of Emulsions in Structured Rectangular Microchannels

Authors: Luma Al-Tamimi, Hassan Farhat, Wessam Hasan

Abstract:

A three-dimensional (3D) hybrid quasi-steady thermal lattice Boltzmann model is developed to couple the effects of surfactant, temperature, interfacial tension, and contact angle. This 3D model is an extended scheme of a previously introduced two-dimensional (2D) hybrid lattice Boltzmann model. The 3D model is used to study the combined multi-physics effects on emulsion systems flowing in rectangular microchannels with and without confinements, where the suspended phase is made of droplets, plugs, or a mixture of both. The simulation results show that emulsion systems with plugs as the suspended phase are more efficient than with droplets, whereas mixed systems that form large plugs through coalescence have even greater efficiency. The 3D contact angle model generates matching results to those of the 2D model, which were validated with experiments. Furthermore, the effects of various confinements on adhering single drop systems are investigated for delineating their influence on the power required for transporting the suspended phase through the channel. It is shown that the deeper the constriction is, the lower the system efficiency. Increasing the surfactant concentration or fluid temperature in a channel with confinement carries a substantial positive effect on oil droplet transportation.

Keywords: lattice Boltzmann method, thermal, contact angle, surfactants, high viscosity ratio, porous media

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2568 Viability of Rice Husk Ash Concrete Brick/Block from Green Electricity in Bangladesh

Authors: Mohammad A. N. M. Shafiqul Karim

Abstract:

As a developing country, Bangladesh has to face numerous challenges. Self Independence in electricity, contributing to climate change by reducing carbon emission and bringing the backward population of society to the mainstream is more challenging for them. Therefore, it is essential to ensure recycled use of local products to the maximum level in every sector. Some private organizations have already worked alongside government to bring the backward population to the mainstream by developing their financial capacities. As rice husk is the largest single category of the total energy supply in Bangladesh. As part of this strategy, rice husk can play a great as a promising renewable energy source, which is readily available, has considerable environmental benefits and can produce electricity and ensure multiple uses of byproducts in construction technology. For the first time in Bangladesh, an experimental multidimensional project depending on Rice Husk Electricity and Rice Husk Ash (RHA) concrete brick/block under Green Eco-Tech Limited has already been started. Project analysis, opportunity, sustainability, the high monitoring component, limitations and finally evaluated data reflecting the viability of establishing more projects using rice husk are discussed in this paper. The by-product of rice husk from the production of green electricity, RHA, can be used for making, in particular, RHA concrete brick/block in Bangladeshi aspects is also discussed here.

Keywords: project analysis, rice husk, rice husk ash concrete brick/block, compressive strength of rice husk ash concrete brick/block

Procedia PDF Downloads 297
2567 Community-Based Assessment Approach to Empower Child with Disabilities: Institutional Study on Deaf Art Community in Yogyakarta, Indonesia

Authors: Mukhamad Fatkhullah, Arfan Fadli, Marini Kristina Situmeang, Siti Hazar Sitorus

Abstract:

The emergence of a community of people with disabilities along with the various works produced has made great progress to open the public eye to their existence in society. This study focuses attention on a community that is suspected to be one of the pioneers in pursuing the movement. It is Deaf Art Community (DAC), a community of persons with disabilities based in Yogyakarta, with deaf and speech-impaired members who use sign language in everyday communication. Knowing the movement of disabled communities is a good thing, the description of the things behind it then important to know as the basis for initiating similar movements. This research focuses on the question of how community of people with disabilities begin to take shape in different regions and interact with collaborative events. Qualitative method with in-depth interview as data collection techniques was used to describe the process of formation and the emergence of community. The analytical unit in the study initially focuses on the subject in the community, but in the process, it develops to institutional analysis. Therefore some informants were determined purposively and expanded using the snowball technique. The theory used in this research is Phenomenology of Alfred Schutz to be able to see reality from the subject and institutional point of view. The results of this study found that the community is formed because the existing educational institutions (both SLB and inclusion) are less able to empower and make children with disabilities become equal with the society. Through the SLB, the presence of children with disabilities becomes isolated from the society, especially in children of his or her age. Therefore, discrimination and labeling will never be separated from society's view. Meanwhile, facilities for the basic needs of children with disabilities can not be fully provided. Besides that, the guarantee of discrimination, glances, and unpleasant behavior from children without disability does not exist, which then indicates that the existing inclusion schools offer only symbolic acceptance. Thus, both in SLB and Inclusive Schools can not empower children with disabilities. Community-based assistance, in this case, has become an alternative to actually empowering children with disabilities. Not only giving them a place to interact, through the same community, children with disabilities will be guided to discover their talents and develop their potential to be self-reliant in the future.

Keywords: children with disabilities, community-based assessment, community empowerment, social equity

Procedia PDF Downloads 263
2566 Influence of Strong Optical Feedback on Frequency Chirp and Lineshape Broadening in High-Speed Semiconductor Laser

Authors: Moustafa Ahmed, Fumio Koyama

Abstract:

Directly-modulated semiconductor lasers, including edge-emitting and vertical-cavity surface-emitting lasers, have received considerable interest recently for use in data transmitters in cost-effective high-speed data centers, metro, and access networks. Optical feedback has been proved as an efficient technique to boost the modulation bandwidth and enhance the speed of the semiconductor laser. However, both the laser linewidth and frequency chirping in directly-modulated lasers are sensitive to both intensity modulation and optical feedback. These effects along width fiber dispersion affect the transmission bit rate and distance in single-mode fiber links. In this work, we continue our recent research on directly-modulated semiconductor lasers with modulation bandwidth in the millimeter-wave band by introducing simultaneous modeling and simulations on both the frequency chirping and lineshape broadening. The lasers are operating under strong optical feedback. The model takes into account the multiple reflections of laser reflections of laser radiation in the external cavity. The analyses are given in terms of the chirp-to-modulated power ratio, and the results are shown for the possible dynamic states of continuous wave, period-1 oscillation, and chaos.

Keywords: chirp, linewidth, optical feedback, semiconductor laser

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2565 Off-Policy Q-learning Technique for Intrusion Response in Network Security

Authors: Zheni S. Stefanova, Kandethody M. Ramachandran

Abstract:

With the increasing dependency on our computer devices, we face the necessity of adequate, efficient and effective mechanisms, for protecting our network. There are two main problems that Intrusion Detection Systems (IDS) attempt to solve. 1) To detect the attack, by analyzing the incoming traffic and inspect the network (intrusion detection). 2) To produce a prompt response when the attack occurs (intrusion prevention). It is critical creating an Intrusion detection model that will detect a breach in the system on time and also challenging making it provide an automatic and with an acceptable delay response at every single stage of the monitoring process. We cannot afford to adopt security measures with a high exploiting computational power, and we are not able to accept a mechanism that will react with a delay. In this paper, we will propose an intrusion response mechanism that is based on artificial intelligence, and more precisely, reinforcement learning techniques (RLT). The RLT will help us to create a decision agent, who will control the process of interacting with the undetermined environment. The goal is to find an optimal policy, which will represent the intrusion response, therefore, to solve the Reinforcement learning problem, using a Q-learning approach. Our agent will produce an optimal immediate response, in the process of evaluating the network traffic.This Q-learning approach will establish the balance between exploration and exploitation and provide a unique, self-learning and strategic artificial intelligence response mechanism for IDS.

Keywords: cyber security, intrusion prevention, optimal policy, Q-learning

Procedia PDF Downloads 238
2564 Performance Assessment of Horizontal Axis Tidal Turbine with Variable Length Blades

Authors: Farhana Arzu, Roslan Hashim

Abstract:

Renewable energy is the only alternative sources of energy to meet the current energy demand, healthy environment and future growth which is considered essential for essential sustainable development. Marine renewable energy is one of the major means to meet this demand. Turbines (both horizontal and vertical) play a vital role for extraction of tidal energy. The influence of swept area on the performance improvement of tidal turbine is a vital factor to study for the reduction of relatively high power generation cost in marine industry. This study concentrates on performance investigation of variable length blade tidal turbine concept that has already been proved as an efficient way to improve energy extraction in the wind industry. The concept of variable blade length utilizes the idea of increasing swept area through the turbine blade extension when the tidal stream velocity falls below the rated condition to maximize energy capture while blade retracts above rated condition. A three bladed horizontal axis variable length blade horizontal axis tidal turbine was modelled by modifying a standard fixed length blade turbine. Classical blade element momentum theory based numerical investigation has been carried out using QBlade software to predict performance. The results obtained from QBlade were compared with the available published results and found very good agreement. Three major performance parameters (i.e., thrust, moment, and power coefficients) and power output for different blade extensions were studied and compared with a standard fixed bladed baseline turbine at certain operational conditions. Substantial improvement in performance coefficient is observed with the increase in swept area of the turbine rotor. Power generation is found to increase in great extent when operating at below rated tidal stream velocity reducing the associated cost per unit electric power generation.

Keywords: variable length blade, performance, tidal turbine, power generation

Procedia PDF Downloads 276
2563 Evaluating the Factors Controlling the Hydrochemistry of Gaza Coastal Aquifer Using Hydrochemical and Multivariate Statistical Analysis

Authors: Madhat Abu Al-Naeem, Ismail Yusoff, Ng Tham Fatt, Yatimah Alias

Abstract:

Groundwater in Gaza strip is increasingly being exposed to anthropic and natural factors that seriously impacted the groundwater quality. Physiochemical data of groundwater can offer important information on changes in groundwater quality that can be useful in improving water management tactics. An integrative hydrochemical and statistical techniques (Hierarchical cluster analysis (HCA) and factor analysis (FA)) have been applied on the existence ten physiochemical data of 84 samples collected in (2000/2001) using STATA, AquaChem, and Surfer softwares to: 1) Provide valuable insight into the salinization sources and the hydrochemical processes controlling the chemistry of groundwater. 2) Differentiate the influence of natural processes and man-made activities. The recorded large diversity in water facies with dominance Na-Cl type that reveals a highly saline aquifer impacted by multiple complex hydrochemical processes. Based on WHO standards, only (15.5%) of the wells were suitable for drinking. HCA yielded three clusters. Cluster 1 is the highest in salinity, mainly due to the impact of Eocene saline water invasion mixed with human inputs. Cluster 2 is the lowest in salinity also due to Eocene saline water invasion but mixed with recent rainfall recharge and limited carbonate dissolution and nitrate pollution. Cluster 3 is similar in salinity to Cluster 2, but with a high diversity of facies due to the impact of many sources of salinity as sea water invasion, carbonate dissolution and human inputs. Factor analysis yielded two factors accounting for 88% of the total variance. Factor 1 (59%) is a salinization factor demonstrating the mixing contribution of natural saline water with human inputs. Factor 2 measure the hardness and pollution which explained 29% of the total variance. The negative relationship between the NO3- and pH may reveal a denitrification process in a heavy polluted aquifer recharged by a limited oxygenated rainfall. Multivariate statistical analysis combined with hydrochemical analysis indicate that the main factors controlling groundwater chemistry were Eocene saline invasion, seawater invasion, sewage invasion and rainfall recharge and the main hydrochemical processes were base ion and reverse ion exchange processes with clay minerals (water rock interactions), nitrification, carbonate dissolution and a limited denitrification process.

Keywords: dendrogram and cluster analysis, water facies, Eocene saline invasion and sea water invasion, nitrification and denitrification

Procedia PDF Downloads 365
2562 A Comparative Analysis of Carbon Footprints of Households in Different Housing Types and Seasons

Authors: Taehyun Kim

Abstract:

As a result of rapid urbanization, energy demands for lighting, heating and cooling of households have been concentrated in metropolitan areas. The energy resources for housing in urban areas are dominantly fossil fuel whose uses contribute to increase cost of living and carbon dioxide (CO2) emission. To achieve environmentally and economically sustainable residential development, it is important to know how energy use and cost of living can be reduced by planning and design. The purpose of this study is to examine which type of building requires less energy for housing. To do so, carbon footprint (CF) quiz survey was employed which estimates the amount of carbon dioxide required to support households’ consumption of energy uses for housing. The housing carbon footprints (HCF) of 500 households of Seoul, Korea in summer and winter were estimated and compared in three major types of housing: single-family (detached), row-house and apartment. In addition, its differences of HCF were estimated between tower and flat type of apartment. The results of T-test and analysis of variance (ANOVA) provide statistical evidence that housing type is related to housing energy use. Average HCF of detached house was higher than other housing types. Between two types of apartment, tower type shows higher HCF than flat type in winter. These findings may provide new perspectives on CF application in sustainable architecture and urban design.

Keywords: analysis of variance, carbon footprint, energy use, housing type

Procedia PDF Downloads 505
2561 Cellulose Enhancement in Wood Used in Pulp Production by Overexpression of Korrigan and Sucrose Synthase Genes

Authors: Anil Kumar, Diwakar Aggarwal, M. Sudhakara Reddy

Abstract:

The wood of Eucalyptus, Populus and bamboos are some important species used as raw material for the manufacture of pulp. However, higher levels of lignin pose a problem during Kraft pulping and yield of pulp is also lower. In order to increase the yield of pulp per unit wood and reduce the use of chemicals during kraft pulping it is important to reduce the lignin content and/or increase cellulose content in wood. Cellulose biosynthesis in wood takes place by the coordinated action of many enzymes. The two important enzymes are KORRIGAN and SUCROSE SYNTHASE. KORRIGAN (Endo-1,4--glucanase) is implicated in the process of editing growing cellulose chains and improvement of the crystallinity of produced cellulose, whereas SUCROSE SYNTHASE is involved in providing substrate (UDP-glucose) for growing cellulose chains. The present study was aimed at the cloning, characterization and overexpression of these genes in Eucalyptus and Populus. An efficient shoot organogenesis protocol from leaf explants taken from micro shoots of the species has been developed. Agrobacterium mediated genetic transformation using Agrobacterium tumefaciens strain EHA105 and LBA4404 harboring binary vector pBI121 was achieved. Both the genes were cloned from cDNA library of Populus deltoides. These were subsequently characterized using various bioinformatics tools. The cloned genes were then inserted into pBI121 under the CaMV35S promotors replacing GUS gene. The constructs were then mobilized into above strains of Agrobacterium and used for the transformation work. Subsequently, genetic transformation of these clones with target genes following already developed protocol is in progress. Four transgenic lines of Eucalyptus tereticornis overexpressing Korrigan gene under the strong constitutive promoters CaMV35S have been developed, which are being further evaluated. Work on development of more transgenic lines overexpressing these genes in Populus and Eucalyptus is also in progress. This presentation will focus on important developments in this direction.

Keywords: Eucalyptus tereticornis, genetic transformation, Kraft pulping Populus deltoides

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2560 A Survey on the Supervision Experience of Full-Time Intern Counseling Psychologist

Authors: Szu-Fan Chen, Cheng-Tseng Lin, Ting-Chia Lien

Abstract:

This study mainly focuses on understanding the current supervision experience of full-time intern counseling psychologists in Taiwan. This study took 197 full-time intern counseling psychologists as the research subjects, including 146 women (74%) and 51 men (26%). In terms of internship sites, the largest number of internships are in school sites (59%), followed by community sites (30%), and fewer in medical fields or corporate sites (only 11%). In addition, a survey was conducted on whether the subjects had full-time jobs before full-time internship. 42% did not have full-time workers, and 48% had full-time workers. However, among those who had full-time workers, 28% were engaged in work related to psychological counseling. 20% are engaged in work unrelated to psychological counseling. In the sample of this study, each person interviewed on average 2.68 internship institutions in total, and the current internship unit is the 2.29th institution interviewed. All (100%) full-time intern psychologists have entered into individual internship contracts with internship institutions. In terms of professional supervisor candidates, a total of 178 (90%) supervisors were appointed by internal personnel of the institution, and a total of 19 (10%) were hired as supervisors from outside the institution. Regarding the form of supervision, it is mostly conducted through individual supervision (98%), and up to 60% is conducted through discussion of written/oral case reports. In terms of supervision satisfaction, 47% were very satisfied, 28% were satisfied, 18% were OK, and 6% were dissatisfied. It is worth noting that the results of this study show that full-time intern counseling psychologists said that they are under pressure to accept supervision (30%). It is recommended that the internship system should standardize the qualification review and evaluation of internship institutions to facilitate institutional control. Furthermore, the personal difficulties of full-time intern psychologists need to be discussed with the internship institution and supervisor from time to time to jointly assist them in completing their professional studies stably and successfully. Finally, it is recommended that future researchers can use the interview method provided by the author to strengthen their understanding of the supervision experience of full-time intern counseling psychologists, so that in the future, this study can provide relevant specific and feasible suggestions for counseling practitioners and future researchers' reference.

Keywords: full-time intern counseling psychologist, supervision experience, full-time intership, supervision

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2559 Neonatal Subcutaneous Fat Necrosis with Severe Hypercalcemia: Case Report

Authors: Atitallah Sofien, Bouyahia Olfa, Krifi farah, Missaoui Nada, Ben Rabeh Rania, Yahyaoui Salem, Mazigh Sonia, Boukthir Samir

Abstract:

Introduction: Subcutaneous fat necrosis of the newborn (SCFN) is a rare acute hypodermatitis characterized by skin lesions in the form of infiltrated, hard plaques and subcutaneous nodules, with a purplish-red color, occurring between the first and sixth week of life. SCFN is generally a benign condition that spontaneously regresses without sequelae, but it can be complicated by severe hypercalcemia. Methodology: This is a retrospective case report of neonatal subcutaneous fat necrosis complicated with severe hypercalcemia and nephrocalcinosis. Results: This is a case of a female newborn with a family history of a hypothyroid mother on Levothyrox, born to non-consanguineous parents and from a well-monitored pregnancy. The newborn was delivered by cesarean section at 39 weeks gestation due to severe preeclampsia. She was admitted to the Neonatal Intensive Care Unit at 1 hour of life for the management of grade 1 perinatal asphyxia and immediate neonatal respiratory distress related to transient respiratory distress. Hospitalization was complicated by a healthcare-associated infection, requiring intravenous antibiotics for ten days, with a good clinical and biological response. On the 20th day of life, she developed skin lesions in the form of indurated purplish-red nodules on the back and on both arms. A SCFN was suspected. A calcium level test was conducted, which returned a result of 3 mmol/L. The rest of the phosphocalcic assessment was normal, with early signs of nephrocalcinosis observed on renal ultrasound. The diagnosis of SCFN complicated by nephrocalcinosis associated with severe hypercalcemia was made, and the condition improved with intravenous hydration and corticosteroid therapy. Conclusion: SCFN is a rare and generally benign hypodermatitis in newborns with an etiology that is still poorly understood. Despite its benign nature, SCFN can be complicated by hypercalcemia, which can sometimes be life-threatening. Therefore, it is important to conduct a thorough skin examination of newborns, especially those with risk factors, to detect and correct any potential hypercalcemia.

Keywords: subcutaneous fat necrosis, newborn, hypercalcemia, nephrocalcinosis

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2558 Noninvasive Neurally Adjusted Ventilation versus Nasal Continuous or Intermittent Positive Airway Pressure for Preterm Infants: A Systematic Review and Meta-Analysis

Authors: Mohammed S. Bhader, Abdullah A. Ghaddaf, Anas Alamoudi, Amal Abualola, Renad Kalantan, Noura Alkhulaifi, Ibrahim Halawani, Mohammed Alhindi

Abstract:

Background: Noninvasive neurally adjusted ventilatory assist (NAVA) is a relatively new mode of noninvasive ventilation with promising clinical and patient-ventilator outcomes for preterm infants. The aim of this systematic review was to compare NAVA to nasal continuous or positive airway pressure (NCPAP) or intermittent positive airway pressure (NIPP) for preterm infants. Methods: We searched the online databases Medline, Embase, and CENTRAL. We included randomized controlled trials (RCTs) that compared NAVA to NCPAP or NIPP for preterm infants < 37 weeks gestational age. We sought to evaluate the following outcomes: noninvasive intubation failure rate, desaturation rate, the fraction of inspired oxygen (FiO2), and length of stay in the neonatal intensive care unit (NICU). We used the mean difference (MD) to represent continuous outcomes, while the odds ratio (OR) was used to represent dichotomous outcomes. Results: A total of 11 RCTs that enrolled 429 preterm infants were deemed eligible. NAVA showed similar clinical outcomes to NCPAP or NIPP with respect to noninvasive intubation failure (RR for NAVA versus NCPAP: 0.82, 95% confidence interval (CI): 0.49 to 1.37), desaturation rate (RR for NAVA versus NCPAP: 0.69, 95%CI: 0.36 to 1.29; RR for NAVA versus NIPP: 0.58, 95%CI: 0.08 to 4.25), FiO2 (MD for NAVA versus NCPAP: –0.01, 95%CI: –0.04 to 0.02; MD for NAVA versus NIPP: –7.16, 95%CI: –22.63 to 8.31), and length of stay in the NICU (MD for NAVA versus NCPAP: 1.34, 95%CI: –4.17 to 6.85). Conclusion: NAVA showed similar clinical and ventilator-related outcomes compared to the usual care noninvasive respiratory support measures NCPAP or NIPP for preterm infants.

Keywords: preterm infants, noninvasive neurally adjusted ventilatory assist, NIV-NAVA, non-invasive ventilation, nasal continuous or positive airway pressure, NCPAP, intermittent positive airway pressure ventilation, NIPP, respiratory distress syndrome, RDS

Procedia PDF Downloads 109