Search results for: solid isotropic material with penalization method
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 24623

Search results for: solid isotropic material with penalization method

10043 Investigating the Role of Supplier Involvement in the Design Process as an Approach for Enhancing Building Maintainability

Authors: Kamal Ahmed, Othman Ayman, Refat Mostafa

Abstract:

The post-construction phase represents a critical milestone in the project lifecycle. This is because design errors and omissions, as well as construction defects, are examined during this phase. The traditional procurement approaches that are commonly adopted in construction projects separate design from construction, which ultimately inhibits contractors, suppliers and other parties from providing the design team with constructive comments and feedback to improve the project design. As a result, a lack of considering maintainability aspects during the design process results in increasing maintenance and operation costs as well as reducing building performance. This research aims to investigate the role of Early Supplier Involvement (ESI) in the design process as an approach to enhancing building maintainability. In order to achieve this aim, a research methodology consisting of a literature review, case studies and a survey questionnaire was designed to accomplish four objectives. Firstly, a literature review was used to examine the concepts of building maintenance, maintainability, the design process and ESI. Secondly, three case studies were presented and analyzed to investigate the role of ESI in enhancing building maintainability during the design process. Thirdly, a survey questionnaire was conducted with a representative sample of Architectural Design Firms (ADFs) in Egypt to investigate their perception and application of ESI towards enhancing building maintainability during the design process. Finally, the research developed a framework to facilitate ESI in the design process in ADFs in Egypt. Data analysis showed that the ‘Difficulty of trusting external parties and sharing information with transparency’ was ranked the highest challenge of ESI in ADFs in Egypt, followed by ‘Legal competitive advantage restrictions’. Moreover, ‘Better estimation for operation and maintenance costs’ was ranked the highest contribution of ESI towards enhancing building maintainability, followed by ‘Reduce the number of operation and maintenance problems or reworks’. Finally, ‘Innovation, technical expertise, and competence’ was ranked the highest supplier’s selection criteria, while ‘paying consultation fees for offering advice and recommendations to the design team’ was ranked the highest form of supplier’s remuneration. The proposed framework represents a synthesis that is creative in thought and adds value to the knowledge in a manner that has not previously occurred.

Keywords: maintenance, building maintainability, building life cycle cost (ICC), material supplier

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10042 An Experimental Study to Control Single Droplet by Actuating Waveform with Preliminary and Suppressing Vibration

Authors: Oke Oktavianty, Tadayuki Kyoutani, Shigeyuki Haruyama, Ken Kaminishi

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For advancing the experiment system standard of Inkjet printer that is being developed, the actual natural period, fire limitation number in droplet weight measurement and observation distance in droplet velocity measurement was investigated. In another side, the study to control the droplet volume in inkjet printer with negative actuating waveform method is still limited. Therefore, the effect of negative waveform with preliminary and suppressing vibration addition on the droplet formation process, droplet shape, volume and velocity were evaluated. The different voltage and print-head temperature were exerted to obtain the optimum preliminary and suppressing vibration. The mechanism of different phenomenon from each waveform was also discussed.

Keywords: inkjet printer, DoD, waveform, preliminary and suppressing vibration

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10041 The Improvement of Environmental Protection through Motor Vehicle Noise Abatement

Authors: Z. Jovanovic, Z. Masonicic, S. Dragutinovic, Z. Sakota

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In this paper, a methodology for noise reduction of motor vehicles in use is presented. The methodology relies on synergic model of noise generation as a function of time. The arbitrary number of motor vehicle noise sources act in concert yielding the generation of the overall noise level of motor vehicle thereafter. The number of noise sources participating in the overall noise level of motor vehicle is subjected to the constraint of the calculation of the acoustic potential of each noise source under consideration. It is the prerequisite condition for the calculation of the acoustic potential of the whole vehicle. The recast form of pertinent set of equations describing the synergic model is laid down and solved by dint of Gauss method. The bunch of results emerged and some of them i.e. those ensuing from model application to MDD FAP Priboj motor vehicle in use are particularly elucidated.

Keywords: noise abatement, MV noise sources, noise source identification, muffler

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10040 Contradictions of Contemporary Culture and Civilization, Processes of Tradition and Innovation

Authors: G. K. Abdigalieva, Z. N. Ismagambetova, T. H. Gabitov, K. A. Biazdikova, A. A. Mukhanbet , B. E. Moldagaliyev, Saira Shamahay

Abstract:

In the article was shown attitude to contemporary traditional culture and cultural heritage preservation issues and features of further development of a culture. Concerning innovation, appeal to cultural heritage, ability of reception of a culture and cultural diffusion in the process of globalization, it is offered further positive development of Kazakhstan’s based human experience and achieved with time. System of traditions is considered as a phenomenon which describes unity, harmony and stability of social body. Contradictions of contemporary culture and civilization, processes of tradition and innovation, cultural changes, and creativities are considered as second side of a society development. Innovation is analyzed as a method of renewal of a culture, tradition and innovation are considered as universal feature of any culture.

Keywords: culture, civilization, innovation, tradition, reality, customs, social relations, morality, values

Procedia PDF Downloads 732
10039 Multi-Sensor Concept in Optical Surface Metrology

Authors: Özgür Tan

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In different fields of industry, there is a huge demand to acquire surface information in the dimension of micrometer up to centimeter in order to characterize functional behavior of products. Thanks to the latest developments, there are now different methods in surface metrology, but it is not possible to find a unique measurement technique which fulfils all the requirements. Depending on the interaction with the surface, regardless of optical or tactile, every method has its own advantages and disadvantages which are given by nature. However new concepts like ‘multi-sensor’, tools in surface metrology can be improved to solve most of the requirements simultaneously. In this paper, after having presented different optical techniques like confocal microscopy, focus variation and white light interferometry, a new approach is presented which combines white-light interferometry with chromatic confocal probing in a single product. Advantages of different techniques can be used for challenging applications.

Keywords: flatness, chromatic confocal, optical surface metrology, roughness, white-light interferometry

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10038 Pathogenic Escherichia Coli Strains and Their Antibiotic Susceptibility Profiles in Cases of Child Diarrhea at Addis Ababa University, College of Health Sciences, Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia

Authors: Benyam Zenebe, Tesfaye Sisay, Gurja Belay, Workabeba Abebe

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Background: The prevalence and antibiogram of pathogenic E. coli strains, which cause diarrhea vary from region to region, and even within countries in the same geographical area. In Ethiopia, diagnostic approaches to E. coli induced diarrhea in children less than five years of age are not standardized. The aim of this study was to determine the involvement of pathogenic E. coli strains in child diarrhea and determine the antibiograms of the isolates in children less than 5 years of age with diarrhea at Addis Ababa University College of Health Sciences TikurAnbessa Specialized Hospital, Addis Ababa, Ethiopia. Methods: A purposive study that included 98 diarrheic children less than five years of age was conducted at Addis Ababa University College of Health Sciences, TikurAnbessa Specialized Hospital, Addis Ababa, Ethiopia to detect pathogenic E. coli biotypes. Stool culture was used to identify presumptive E. coliisolates. Presumptive isolates were confirmed by biochemical tests, and antimicrobial susceptibility tests were performed on confirmed E. coli isolates by the disk diffusion method. DNA was extracted from confirmed isolates by a heating method and subjected to Polymerase Chain Reaction or the presence of virulence genes. Amplified PCR products were analyzed by agarose gel electrophoresis. Data were collected on child demographics and clinical conditions using administered questionnaires. The prevalence of E. coli strains from the total diarrheic children, and the prevalence of pathogenic strains from total E. coli isolates along with their susceptibility profiles; the distribution of pathogenic E.coli biotypes among different age groups and between the sexes were determined by using descriptive statistics. Result: Out of 98 stool specimens collected from diarrheic children less than 5 years of age, 75 presumptive E. coli isolates were identified by culture; further confirmation by biochemical tests showed that only 56 of the isolates were E. coli; 29 of the isolates were found in male children and 27 of them in female children. Out of the 58 isolates of E. coli, 25 pathotypes belonging to different classes of pathogenic strains: STEC, EPEC, EHEC, EAEC were detected by using the PCR technique. Pathogenic E. coli exhibited high rates of antibiotic resistance to many of the antibiotics tested. Moreover, they exhibited multiple drug resistance. Conclusion: This study found that the isolation rate of E. coli and the involvement of antibiotic-resistant pathogenic E. coli in diarrheic children is prominent, and hence focus should be given on the diagnosis and antimicrobial sensitivity testing of pathogenic E. coli at Addis Ababa University College of Health Sciences TikurAnbessa Specialized Hospital. Among antibiotics tested, Cefotitan could be a drug of choice to treat E. coli.

Keywords: antibiotic susceptibility profile, children, diarrhea, E. coli, pathogenic

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10037 The Culture of Extrajudicial Executions: An Investigative Study of the Philippines’ Fifth Republic

Authors: Nathalie Quinto, Danielle Solancho

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In 1986, after Marcos’ Martial Law of 1972, the Philippines revised its constitution for the fifth time, under the Aquino Administration. Extrajudicial violence was expected to be lessened, if not completely eradicated after this was passed. However, state-sponsored executions continued to persist even in the present time. There are currently identified policy gaps when it comes to extrajudicial cases, as there is no generally accepted definition of the term in the Philippines. In this paper, a triangulation method of historically published papers, key informant interviews, and focus group discussions of academics, scholars, and people who are involved in various cases found, was utilized for the methodology. This paper explores the establishment of a normalized system of state-sponsored executions in the country and why the state resorts to this kind of action. It found that due to a weak political, and social institution, a culture of extrajudicial executions was established.

Keywords: extrajudicial execution, human rights, justice, security

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10036 Variables, Annotation, and Metadata Schemas for Early Modern Greek

Authors: Eleni Karantzola, Athanasios Karasimos, Vasiliki Makri, Ioanna Skouvara

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Historical linguistics unveils the historical depth of languages and traces variation and change by analyzing linguistic variables over time. This field of linguistics usually deals with a closed data set that can only be expanded by the (re)discovery of previously unknown manuscripts or editions. In some cases, it is possible to use (almost) the entire closed corpus of a language for research, as is the case with the Thesaurus Linguae Graecae digital library for Ancient Greek, which contains most of the extant ancient Greek literature. However, concerning ‘dynamic’ periods when the production and circulation of texts in printed as well as manuscript form have not been fully mapped, representative samples and corpora of texts are needed. Such material and tools are utterly lacking for Early Modern Greek (16th-18th c.). In this study, the principles of the creation of EMoGReC, a pilot representative corpus of Early Modern Greek (16th-18th c.) are presented. Its design follows the fundamental principles of historical corpora. The selection of texts aims to create a representative and balanced corpus that gives insight into diachronic, diatopic and diaphasic variation. The pilot sample includes data derived from fully machine-readable vernacular texts, which belong to 4-5 different textual genres and come from different geographical areas. We develop a hierarchical linguistic annotation scheme, further customized to fit the characteristics of our text corpus. Regarding variables and their variants, we use as a point of departure the bundle of twenty-four features (or categories of features) for prose demotic texts of the 16th c. Tags are introduced bearing the variants [+old/archaic] or [+novel/vernacular]. On the other hand, further phenomena that are underway (cf. The Cambridge Grammar of Medieval and Early Modern Greek) are selected for tagging. The annotated texts are enriched with metalinguistic and sociolinguistic metadata to provide a testbed for the development of the first comprehensive set of tools for the Greek language of that period. Based on a relational management system with interconnection of data, annotations, and their metadata, the EMoGReC database aspires to join a state-of-the-art technological ecosystem for the research of observed language variation and change using advanced computational approaches.

Keywords: early modern Greek, variation and change, representative corpus, diachronic variables.

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10035 Numerical Investigation of a Supersonic Ejector for Refrigeration System

Authors: Karima Megdouli, Bourhan Taschtouch

Abstract:

Supersonic ejectors have many applications in refrigeration systems. And improving ejector performance is the key to improve the efficiency of these systems. One of the main advantages of the ejector is its geometric simplicity and the absence of moving parts. This paper presents a theoretical model for evaluating the performance of a new supersonic ejector configuration for refrigeration system applications. The relationship between the flow field and the key parameters of the new configuration has been illustrated by analyzing the Mach number and flow velocity contours. The method of characteristics (MOC) is used to design the supersonic nozzle of the ejector. The results obtained are compared with those obtained by CFD. The ejector is optimized by minimizing exergy destruction due to irreversibility and shock waves. The optimization converges to an efficient optimum solution, ensuring improved and stable performance over the whole considered range of uncertain operating conditions.

Keywords: supersonic ejector, theoretical model, CFD, optimization, performance

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10034 Design Exploration on Mixed-Use Development of Island House: Take the Southeast Coastal Area of Chinese as an Example

Authors: Fu Jiayan, Wang Zhu, Sun Jiaojiao

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Mixed-use development is one of the most important trends in new island house transformation along southeast coastal area in China. Unique island geographical environment and profound fishing village culture coexist for a long time in this. With artistic creation for the purpose of the "live-work" houses are in a large number of emergence, however, still lack of systematic strategy. Based on space effect from marine resources to regional human settlements, this article teases out the evolution regularity of island settlement context and architectural form, then, puts forward the formation mechanism and construction model of art island houses. Thereby, to further explore space design method and site creation strategy of mixed-use development.

Keywords: mixed-use, island house, art creation, Southeast Coastal Area of Chinese

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10033 Two-Stage Approach for Solving the Multi-Objective Optimization Problem on Combinatorial Configurations

Authors: Liudmyla Koliechkina, Olena Dvirna

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The statement of the multi-objective optimization problem on combinatorial configurations is formulated, and the approach to its solution is proposed. The problem is of interest as a combinatorial optimization one with many criteria, which is a model of many applied tasks. The approach to solving the multi-objective optimization problem on combinatorial configurations consists of two stages; the first is the reduction of the multi-objective problem to the single criterion based on existing multi-objective optimization methods, the second stage solves the directly replaced single criterion combinatorial optimization problem by the horizontal combinatorial method. This approach provides the optimal solution to the multi-objective optimization problem on combinatorial configurations, taking into account additional restrictions for a finite number of steps.

Keywords: discrete set, linear combinatorial optimization, multi-objective optimization, Pareto solutions, partial permutation set, structural graph

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10032 Modern State of the Universal Modeling for Centrifugal Compressors

Authors: Y. Galerkin, K. Soldatova, A. Drozdov

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The 6th version of Universal modeling method for centrifugal compressor stage calculation is described. Identification of the new mathematical model was made. As a result of identification the uniform set of empirical coefficients is received. The efficiency definition error is 0,86 % at a design point. The efficiency definition error at five flow rate points (except a point of the maximum flow rate) is 1,22 %. Several variants of the stage with 3D impellers designed by 6th version program and quasi three-dimensional calculation programs were compared by their gas dynamic performances CFD (NUMECA FINE TURBO). Performance comparison demonstrated general principles of design validity and leads to some design recommendations.

Keywords: compressor design, loss model, performance prediction, test data, model stages, flow rate coefficient, work coefficient

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10031 Damage Assessment Based on Full-Polarimetric Decompositions in the 2017 Colombia Landslide

Authors: Hyeongju Jeon, Yonghyun Kim, Yongil Kim

Abstract:

Synthetic Aperture Radar (SAR) is an effective tool for damage assessment induced by disasters due to its all-weather and night/day acquisition capability. In this paper, the 2017 Colombia landslide was observed using full-polarimetric ALOS/PALSAR-2 data. Polarimetric decompositions, including the Freeman-Durden decomposition and the Cloude decomposition, are utilized to analyze the scattering mechanisms changes before and after-landslide. These analyses are used to detect the damaged areas induced by the landslide. Experimental results validate the efficiency of the full polarimetric SAR data since the damaged areas can be well discriminated. Thus, we can conclude the proposed method using full polarimetric data has great potential for damage assessment of landslides.

Keywords: Synthetic Aperture Radar (SAR), polarimetric decomposition, damage assessment, landslide

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10030 The Awareness of Sustainability Concerns in Design Studio Education Process: A Case from TOBB ETU University, Interior Architecture Department in Turkey

Authors: Pelin Atav, Gözen Güner Aktaş, Nur Ayalp

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Today’s world has started to develop design process within an interdisciplinary working environment. There is an aim of creating the most permanent design for the future. While satisfying people’s needs, environment and people relationships should be considered. When this relationship was considered for the future, the sustainability term comes to mind. The term Sustainability has been adapted very well by designer and architects. It is also one of the main and significant parts of the design process. As the education process cultivates the future professionals, the awareness of those concepts in the education process has a vital importance. The question is stated as thus: Are the 3rd and 4th year design studio students, familiar and sensitive to the concept of sustainability in the TOBB ETU University Interior Design Studio. Design studios and the instructors should be taken into consideration while this sustainability term is taught. The term "Sustainability" can not be learned without making any application in the actual real world. While students make this study, They can have the chance to search the topic of sustainability step by step. Due to having various extent, sustainability term becomes quite a comprehensive issue. In order not to create negative consequences, designers and architects work by adapting this term. In terms of material, construction process, lighting, building service, furniture, systems that are used, energy consumption issues that are considered and creating positive drawbacks for the future are aimed. This research is aimed at how university education shapes designer’s works in terms of sustainability. By giving a project that is a main interest in the field of sustainability, students are expected to reach well-thought-of results and analysis. Project process were conducted with instructor and student studies together. According to critics from their instructors, students try to product well- designed results. TOBB University was choosen as a research area situated in Ankara in Turkey. Third and fourth class (interior designer/architect department) students who are from the Faculty of Fine Arts Design and Architecture are the subject group selected for this study. Aim of this study is demonstrating sustainability as a term having application in design studio. Thus, awareness of sustainability terms will be evaluated and its development process in the university education will be observed. Consequently, results that are expected is how sustainability term is conducted in project and for the sustainability term awareness in design studios and their projects have been sufficient or not.

Keywords: design education, design process, interior design studios, sustainability

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10029 River's Bed Level Changing Pattern Due to Sedimentation, Case Study: Gash River, Kassala, Sudan

Authors: Faisal Ali, Hasssan Saad Mohammed Hilmi, Mustafa Mohamed, Shamseddin Musa

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The Gash rivers an ephemeral river, it usually flows from July to September, it has a braided pattern with high sediment content, of 15200 ppm in suspension, and 360 kg/sec as bed load. The Gash river bed has an average slope of 1.3 m/Km. The objectives of this study were: assessing the Gash River bed level patterns; quantifying the annual variations in Gash bed level; and recommending a suitable method to reduce the sediment accumulation on the Gash River bed. The study covered temporally the period 1905-2013 using datasets included the Gash river flows, and the cross sections. The results showed that there is an increasing trend in the river bed of 5 cm3 per year. This is resulted in changing the behavior of the flood routing and consequently the flood hazard is tremendously increased in Kassala city.

Keywords: bed level, cross section, gash river, sedimentation

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10028 Laser-Dicing Modeling: Implementation of a High Accuracy Tool for Laser-Grooving and Cutting Application

Authors: Jeff Moussodji, Dominique Drouin

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The highly complex technology requirements of today’s integrated circuits (ICs), lead to the increased use of several materials types such as metal structures, brittle and porous low-k materials which are used in both front end of line (FEOL) and back end of line (BEOL) process for wafer manufacturing. In order to singulate chip from wafer, a critical laser-grooving process, prior to blade dicing, is used to remove these layers of materials out of the dicing street. The combination of laser-grooving and blade dicing allows to reduce the potential risk of induced mechanical defects such micro-cracks, chipping, on the wafer top surface where circuitry is located. It seems, therefore, essential to have a fundamental understanding of the physics involving laser-dicing in order to maximize control of these critical process and reduce their undesirable effects on process efficiency, quality, and reliability. In this paper, the study was based on the convergence of two approaches, numerical and experimental studies which allowed us to investigate the interaction of a nanosecond pulsed laser and BEOL wafer materials. To evaluate this interaction, several laser grooved samples were compared with finite element modeling, in which three different aspects; phase change, thermo-mechanical and optic sensitive parameters were considered. The mathematical model makes it possible to highlight a groove profile (depth, width, etc.) of a single pulse or multi-pulses on BEOL wafer material. Moreover, the heat affected zone, and thermo-mechanical stress can be also predicted as a function of laser operating parameters (power, frequency, spot size, defocus, speed, etc.). After modeling validation and calibration, a satisfying correlation between experiment and modeling, results have been observed in terms of groove depth, width and heat affected zone. The study proposed in this work is a first step toward implementing a quick assessment tool for design and debug of multiple laser grooving conditions with limited experiments on hardware in industrial application. More correlations and validation tests are in progress and will be included in the full paper.

Keywords: laser-dicing, nano-second pulsed laser, wafer multi-stack, multiphysics modeling

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10027 An Integrated Framework for Wind-Wave Study in Lakes

Authors: Moien Mojabi, Aurelien Hospital, Daniel Potts, Chris Young, Albert Leung

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The wave analysis is an integral part of the hydrotechnical assessment carried out during the permitting and design phases for coastal structures, such as marinas. This analysis aims in quantifying: i) the Suitability of the coastal structure design against Small Craft Harbour wave tranquility safety criterion; ii) Potential environmental impacts of the structure (e.g., effect on wave, flow, and sediment transport); iii) Mooring and dock design and iv) Requirements set by regulatory agency’s (e.g., WSA section 11 application). While a complex three-dimensional hydrodynamic modelling approach can be applied on large-scale projects, the need for an efficient and reliable wave analysis method suitable for smaller scale marina projects was identified. As a result, Tetra Tech has developed and applied an integrated analysis framework (hereafter TT approach), which takes the advantage of the state-of-the-art numerical models while preserving the level of simplicity that fits smaller scale projects. The present paper aims to describe the TT approach and highlight the key advantages of using this integrated framework in lake marina projects. The core of this methodology is made by integrating wind, water level, bathymetry, and structure geometry data. To respond to the needs of specific projects, several add-on modules have been added to the core of the TT approach. The main advantages of this method over the simplified analytical approaches are i) Accounting for the proper physics of the lake through the modelling of the entire lake (capturing real lake geometry) instead of a simplified fetch approach; ii) Providing a more realistic representation of the waves by modelling random waves instead of monochromatic waves; iii) Modelling wave-structure interaction (e.g. wave transmission/reflection application for floating structures and piles amongst others); iv) Accounting for wave interaction with the lakebed (e.g. bottom friction, refraction, and breaking); v) Providing the inputs for flow and sediment transport assessment at the project site; vi) Taking in consideration historical and geographical variations of the wind field; and vii) Independence of the scale of the reservoir under study. Overall, in comparison with simplified analytical approaches, this integrated framework provides a more realistic and reliable estimation of wave parameters (and its spatial distribution) in lake marinas, leading to a realistic hydrotechnical assessment accessible to any project size, from the development of a new marina to marina expansion and pile replacement. Tetra Tech has successfully utilized this approach since many years in the Okanagan area.

Keywords: wave modelling, wind-wave, extreme value analysis, marina

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10026 Ficus Carica as Adsorbent for Removal of Phenol from Aqueous Solutions: Modelling and Optimization

Authors: Tizi Hayet, Berrama Tarek, Bounif Nadia

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Phenol and its derivatives are organic compounds utilized in the chemical industry. They are introduced into the environment by accidental spills and illegal release of industrial and municipal wastewater. Phenols are organic intermediaries that considered as potential pollutants. Adsorption is one of the purification and separation techniques used in this area. Algeria produces annually 131000 tones of fig; therefore, a large amount of fig leaves is generated, and the conversion of this waste into adsorbent allows the valorization of agricultural residue. The main purpose of this present work is to describe an application of the statistical method for modeling and optimization of the conditions of the phenol (Ph) adsorption from agricultural by-product locally available (fig leaves). The best experimental performance of Ph elimination on the adsorbent was obtained with: Adsorbent concentration (X2) = 0.2 g L-1; Initial concentration (X3) = 150 mg L-1; Speed agitation (X1) = 300 rpm.

Keywords: low-cost adsorbents, fig leaves, full factorial design, phenol, biosorption

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10025 The Role of Nickel on the High-Temperature Corrosion of Modell Alloys (Stainless Steels) before and after Breakaway Corrosion at 600°C: A Microstructural Investigation

Authors: Imran Hanif, Amanda Persdotter, Sedigheh Bigdeli, Jesper Liske, Torbjorn Jonsson

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Renewable fuels such as biomass/waste for power production is an attractive alternative to fossil fuels in order to achieve a CO₂ -neutral power generation. However, the combustion results in the release of corrosive species. This puts high demands on the corrosion resistance of the alloys used in the boiler. Stainless steels containing nickel and/or nickel containing coatings are regarded as suitable corrosion resistance material especially in the superheater regions. However, the corrosive environment in the boiler caused by the presence of water vapour and reactive alkali very rapidly breaks down the primary protection, i.e., the Cr-rich oxide scale formed on stainless steels. The lifetime of the components, therefore, relies on the properties of the oxide scale formed after breakaway, i.e., the secondary protection. The aim of the current study is to investigate the role of varying nickel content (0–82%) on the high-temperature corrosion of model alloys with 18% Cr (Fe in balance) in the laboratory mimicking industrial conditions at 600°C. The influence of nickel is investigated on both the primary protection and especially the secondary protection, i.e., the scale formed after breakaway, during the oxidation/corrosion process in the dry O₂ (primary protection) and more aggressive environment such as H₂O, K₂CO₃ and KCl (secondary protection). All investigated alloys experience a very rapid loss of the primary protection, i.e., the Cr-rich (Cr, Fe)₂O₃, and the formation of secondary protection in the aggressive environments. The microstructural investigation showed that secondary protection of all alloys has a very similar microstructure in all more aggressive environments consisting of an outward growing iron oxide and inward growing spinel-oxide (Fe, Cr, Ni)₃O₄. The oxidation kinetics revealed that it is possible to influence the protectiveness of the scale formed after breakaway (secondary protection) through the amount of nickel in the alloy. The difference in oxidation kinetics of the secondary protection is linked to the microstructure and chemical composition of the complex spinel-oxide. The detailed microstructural investigations were carried out using the extensive analytical techniques such as electron back scattered diffraction (EBSD), energy dispersive X-rays spectroscopy (EDS) via the scanning and transmission electron microscopy techniques and results are compared with the thermodynamic calculations using the Thermo-Calc software.

Keywords: breakaway corrosion, EBSD, high-temperature oxidation, SEM, TEM

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10024 Incidence of Fungal Infections and Mycotoxicosis in Pork Meat and Pork By-Products in Egyptian Markets

Authors: Ashraf Samir Hakim, Randa Mohamed Alarousy

Abstract:

The consumption of food contaminated with molds (microscopic filamentous fungi) and their toxic metabolites results in the development of food-borne mycotoxicosis. The spores of molds are ubiquitously spread in the environment and can be detected everywhere. Ochratoxin A is a potentially carcinogenic fungal toxin found in a variety of food commodities , not only is considered the most abundant and hence the most commonly detected member but also is the most toxic one.Ochratoxin A is the most abundant and hence the most commonly detected member, but is also the most toxic of the three. A very limited research works concerning foods of porcine origin in Egypt were obtained in spite of presence a considerable swine population and consumers. In this study, the quality of various ready-to-eat local and imported pork meat and meat byproducts sold in Egyptian markets as well as edible organs as liver and kidney were assessed for the presence of various molds and their toxins as a raw material. Mycological analysis was conducted on (n=110) samples which included pig livers n=10 and kidneys n=10 from the Basateen slaughter house; local n=70 and 20 imported processed pork meat byproducts.The isolates were identified using traditional mycological and biochemical tests while, Ochratoxin A levels were quantitatively analyzed using the high performance liquid. Results of conventional mycological tests for detecting the presence of fungal growth (yeasts or molds) were negative, while the results of mycotoxins concentrations were be greatly above the permiceable limits or "tolerable weekly intake" (TWI) of ochratoxin A established by EFSA in 2006 in local pork and pork byproducts while the imported samples showed a very slightly increasing.Since ochratoxin A is stable and generally resistant to heat and processing, control of ochratoxin A contamination lies in the control of the growth of the toxin-producing fungi. Effective prevention of ochratoxin A contamination therefore depends on good farming and agricultural practices. Good Agricultural Practices (GAP) including methods to reduce fungal infection and growth during harvest, storage, transport and processing provide the primary line of defense against contamination with ochratoxin A. To the best of our knowledge this is the first report of mycological assessment, especially the mycotoxins in pork byproducts in Egypt.

Keywords: Egyptian markets, mycotoxicosis, ochratoxin A, pork meat, pork by-products

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10023 Design and Fabrication of a Scaffold with Appropriate Features for Cartilage Tissue Engineering

Authors: S. S. Salehi, A. Shamloo

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Poor ability of cartilage tissue when experiencing a damage leads scientists to use tissue engineering as a reliable and effective method for regenerating or replacing damaged tissues. An artificial tissue should have some features such as biocompatibility, biodegradation and, enough mechanical properties like the original tissue. In this work, a composite hydrogel is prepared by using natural and synthetic materials that has high porosity. Mechanical properties of different combinations of polymers such as modulus of elasticity were tested, and a hydrogel with good mechanical properties was selected. Bone marrow derived mesenchymal stem cells were also seeded into the pores of the sponge, and the results showed the adhesion and proliferation of cells within the hydrogel after one month. In comparison with previous works, this study offers a new and efficient procedure for the fabrication of cartilage like tissue and further cartilage repair.

Keywords: cartilage tissue engineering, hydrogel, mechanical strength, mesenchymal stem cell

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10022 Study of Durability of Porous Polymer Materials, Glass-Fiber-Reinforced Polyurethane Foam (R-PUF) in MarkIII Containment Membrane System

Authors: Florent Cerdan, Anne-Gaëlle Denay, Annette Roy, Jean-Claude Grandidier, Éric Laine

Abstract:

The insulation of MarkIII membrane of the Liquid Natural Gas Carriers (LNGC) consists of a load- bearing system made of panels in reinforced polyurethane foam (R-PUF). During the shipping, the cargo containment shall be potentially subject to risk events which can be water leakage through the wall ballast tank. The aim of these present works is to further develop understanding of water transfer mechanisms and water effect on properties of R-PUF. This multi-scale approach contributes to improve the durability. Macroscale / Mesoscale Firstly, the use of the gravimetric technique has allowed to define, at room temperature, the water transfer mechanisms and kinetic diffusion, in the R-PUF. The solubility follows a first kinetic fast growing connected to the water absorption by the micro-porosity, and then evolves linearly slowly, this second stage is connected to molecular diffusion and dissolution of water in the dense membranes polyurethane. Secondly, in the purpose of improving the understanding of the transfer mechanism, the study of the evolution of the buoyant force has been established. It allowed to identify the effect of the balance of total and partial pressure of mixture gas contained in pores surface. Mesoscale / Microscale The differential scanning calorimetry (DSC) and Dynamical Mechanical Analysis (DMA), have been used to investigate the hydration of the hard and soft segments of the polyurethane matrix. The purpose was to identify the sensitivity of these two phases. It been shown that the glass transition temperatures shifts towards the low temperatures when the solubility of the water increases. These observations permit to conclude to a plasticization of the polymer matrix. Microscale The Fourier Transform Infrared (FTIR) study has been used to investigate the characterization of functional groups on the edge, the center and mid-way of the sample according the duration of submersion. More water there is in the material, more the water fix themselves on the urethanes groups and more specifically on amide groups. The pic of C=O urethane shifts at lower frequencies quickly before 24 hours of submersion then grows slowly. The intensity of the pic decreases more flatly after that.

Keywords: porous materials, water sorption, glass transition temperature, DSC, DMA, FTIR, transfer mechanisms

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10021 Sloshing Response of Liquid in Prismatic Container under Oscillation

Authors: P. R. Maiti, S. K. Bhattacharyya

Abstract:

Sloshing is a physical phenomenon characterized by the oscillation of unrestrained free surface of liquid in a partially liquid filled container subjected to external excitation. Determination of sloshing frequency in container is important to avoid resonance condition of the system. The complex behavior of the free surface movement and its combined mode of vibration make difficulty for exact analysis of sloshing. In the present study, numerical analysis is carried out for a partially liquid filled tank under external forces. Boundary element approach is used to formulate the sloshing problem in two -dimensional prismatic container with potential flow. Effort has been made to find slosh response for two dimensional problems in partially liquid filled prismatic container.

Keywords: sloshing, boundary element method, prismatic container, oscillation

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10020 Using Cooperation Approaches at Different Levels of Artificial Bee Colony Method

Authors: Vahid Zeighami, Mohsen Ghsemi, Reza Akbari

Abstract:

In this work, a Multi-Level Artificial Bee Colony (called MLABC) is presented. In MLABC two species are used. The first species employs n colonies in which each of the them optimizes the complete solution vector. The cooperation between these colonies is carried out by exchanging information through a leader colony, which contains a set of elite bees. The second species uses a cooperative approach in which the complete solution vector is divided to k sub-vectors, and each of these sub-vectors is optimized by a a colony. The cooperation between these colonies is carried out by compiling sub-vectors into the complete solution vector. Finally, the cooperation between two species is obtained by exchanging information between them. The proposed algorithm is tested on a set of well known test functions. The results show that MLABC algorithms provide efficiency and robustness to solve numerical functions.

Keywords: artificial bee colony, cooperative, multilevel cooperation, vector

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10019 Performance Assessment of GSO Satellites before and after Enhancing the Pointing Effect

Authors: Amr Emam, Joseph Victor, Mohamed Abd Elghany

Abstract:

The paper presents the effect of the orbit inclination on the pointing error of the satellite antenna and consequently on its footprint on earth for a typical Ku- band payload system. The performance assessment is examined both theoretically and by means of practical measurements, taking also into account all additional sources of pointing errors, such as East-West station keeping, orbit eccentricity and actual attitude control performance. An implementation and computation of the sinusoidal biases in satellite roll and pitch used to compensate the pointing error of the satellite antenna coverage is studied and evaluated before and after the pointing corrections performed. A method for evaluation of the performance of the implemented biases has been introduced through measuring satellite received level from a tracking 11m and fixed 4.8m transmitting antenna before and after the implementation of the pointing corrections.

Keywords: satellite, inclined orbit, pointing errors, coverage optimization

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10018 Mechanical Properties and Microstructure of Ultra-High Performance Concrete Containing Fly Ash and Silica Fume

Authors: Jisong Zhang, Yinghua Zhao

Abstract:

The present study investigated the mechanical properties and microstructure of Ultra-High Performance Concrete (UHPC) containing supplementary cementitious materials (SCMs), such as fly ash (FA) and silica fume (SF), and to verify the synergistic effect in the ternary system. On the basis of 30% fly ash replacement, the incorporation of either 10% SF or 20% SF show a better performance compared to the reference sample. The efficiency factor (k-value) was calculated as a synergistic effect to predict the compressive strength of UHPC with these SCMs. The SEM of micrographs and pore volume from BJH method indicate a high correlation with compressive strength. Further, an artificial neural networks model was constructed for prediction of the compressive strength of UHPC containing these SCMs.

Keywords: artificial neural network, fly ash, mechanical properties, ultra-high performance concrete

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10017 Improved K-Means Clustering Algorithm Using RHadoop with Combiner

Authors: Ji Eun Shin, Dong Hoon Lim

Abstract:

Data clustering is a common technique used in data analysis and is used in many applications, such as artificial intelligence, pattern recognition, economics, ecology, psychiatry and marketing. K-means clustering is a well-known clustering algorithm aiming to cluster a set of data points to a predefined number of clusters. In this paper, we implement K-means algorithm based on MapReduce framework with RHadoop to make the clustering method applicable to large scale data. RHadoop is a collection of R packages that allow users to manage and analyze data with Hadoop. The main idea is to introduce a combiner as a function of our map output to decrease the amount of data needed to be processed by reducers. The experimental results demonstrated that K-means algorithm using RHadoop can scale well and efficiently process large data sets on commodity hardware. We also showed that our K-means algorithm using RHadoop with combiner was faster than regular algorithm without combiner as the size of data set increases.

Keywords: big data, combiner, K-means clustering, RHadoop

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10016 General and Sport Specific Fitness Testing Practices: Global Developments

Authors: Peter Smolianov, Jed Smith, Lisa Chen, Steven Dion, Christopher Schoen, Jaclyn Norberg

Abstract:

This study compared general conditioning and sport specific fitness tests used in China, European Union (EU), Russia, and the United States. A constant content comparison method was used to identify the differences. Data from the study indicated that there were shared test components, including aerobic fitness, muscular strength, endurance, and flexibility. However, the testing components and items, as well as the cut-off values of the analyzed tests varied by country for the same gender and age. Culturally unique methods of testing and preparing for the tests were identified. Additionally, evidence revealed support for lifelong fitness and long-term sport participation through comprehensive fitness and wellness guidelines for different age groups and through new internet-based technologies.

Keywords: fitness testing, global trends, new developments, worldwide comparison

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10015 Patterns of Eosinophilia in Cardiac Patients and its Association with Endomyocardial Disease Presenting to Tertiary Care Hospital in Peshawar

Authors: Rashid Azeem

Abstract:

Introduction: Eosinophilia, which can be categorized as mild, moderate, and severe form on the basis of increasing eosinophil counts, might be responsible for a wide range of cardiac manifestations, varying from a simple myocarditis to a severe state like endomyocardial fibrosis. Eosinophils are involved in the pathogenesis of a variety of cardiovascular disorder like Loffler endocarditis, eosinophilic granulomatosis with polyangitis (EGPH), and hyper eosinophilic (HES). Among them HES carries and incidence rate b/w 48% and 75% and is the main causes of cardiac motility and mobility due to eosinophilia involvement. Aims and objectives: The aim of this study is to determine the frequency of eosinophilia in cardiac patients and to ascertain the evidence of endomyocardial diseases in eosinophilic patients in a cardiology institution Material and Methods: This cross sectional analytical study was conducted in hematology Department of Peshawar institute of Cardiology after approval from hospital ethical and research committee. All 70 patients were subjected to detailed history and clinical examination. Investigation like CBC, Chest X-ray, ECG, Echo, Angiography findings were used to monitor patient’s clinical status. Data is analyzed using SPSS version 25 and MS Excel. Results: Out of 70 patients in our study, a total of 66 patients(94 %) shows evidence of cardiac manifestations. In our study, we have observed a number of abnormal ECG patterns in cardiac patients presenting with eosinophilia, like T wave changes, loss of R wave, sinus bradycardia with LVH strain, and ST wave abnormality. abnormal echocardiographic findings were observed in our patients, like valvular abnormalities (in 45.7%), RWMA abnormalities (in 2.8%), isolated ventricular dysfunction (in 21.4%), and in 10% patients, normal echocardiography. We further noted abnormal coronary angiography findings in cardiac patients with eosinophilia ranging from single vessel to multi vessel occlusions. Conclusions: Eosinophils are involved in the pathogenesis of a variety of cardiovascular disorders which can be detected by various diagnostic means, and the severity of the disease increases with time and with increasing eosinophil count ranging from simple myocarditis to a fatal condition like endomyocardial fibrosis. Thus, increased eosinophilic count as a laboratory parameter in cardiac patients may be a sign of endomyocardial damage which will further help cardiologist to intervene more aggressively then routine approach to a cardiac patient.

Keywords: eosinophilia, endomyocardial fibrosis, cardiac, hypereosinophilic syndrome

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10014 Node Insertion in Coalescence Hidden-Variable Fractal Interpolation Surface

Authors: Srijanani Anurag Prasad

Abstract:

The Coalescence Hidden-variable Fractal Interpolation Surface (CHFIS) was built by combining interpolation data from the Iterated Function System (IFS). The interpolation data in a CHFIS comprises a row and/or column of uncertain values when a single point is entered. Alternatively, a row and/or column of additional points are placed in the given interpolation data to demonstrate the node added CHFIS. There are three techniques for inserting new points that correspond to the row and/or column of nodes inserted, and each method is further classified into four types based on the values of the inserted nodes. As a result, numerous forms of node insertion can be found in a CHFIS.

Keywords: fractal, interpolation, iterated function system, coalescence, node insertion, knot insertion

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