Search results for: event structure
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8669

Search results for: event structure

4349 The Physics of Turbulence Generation in a Fluid: Numerical Investigation Using a 1D Damped-MNLS Equation

Authors: Praveen Kumar, R. Uma, R. P. Sharma

Abstract:

This study investigates the generation of turbulence in a deep-fluid environment using a damped 1D-modified nonlinear Schrödinger equation model. The well-known damped modified nonlinear Schrödinger equation (d-MNLS) is solved using numerical methods. Artificial damping is added to the MNLS equation, and turbulence generation is investigated through a numerical simulation. The numerical simulation employs a finite difference method for temporal evolution and a pseudo-spectral approach to characterize spatial patterns. The results reveal a recurring periodic pattern in both space and time when the nonlinear Schrödinger equation is considered. Additionally, the study shows that the modified nonlinear Schrödinger equation disrupts the localization of structure and the recurrence of the Fermi-Pasta-Ulam (FPU) phenomenon. The energy spectrum exhibits a power-law behavior, closely following Kolmogorov's spectra steeper than k⁻⁵/³ in the inertial sub-range.

Keywords: water waves, modulation instability, hydrodynamics, nonlinear Schrödinger's equation

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4348 Meaningful General Education Reform: Integrating Core Curricula and Institutional Values

Authors: Michael W. Markowitz

Abstract:

A central element of higher education today is the “core” or “general education” curriculum: that configuration of courses that often encompasses the essence of liberal arts education. Ensuring that such offerings reflect the mission and values of the institution is a challenge faced by most college and universities, often more than once. This paper presents an action model of program planning designed to structure the processes of developing, implementing and revising core curricula in a manner consistent with key institutional goals and objectives. Through presentation of a case study from a university in the United States, the elements of needs assessment, stakeholder investment and collaborative compromise are shown as key components of a planning strategy that can produce a general education program that is comprehensive, academically rigorous, assessable and mission consistent. The paper concludes with recommendations for both the implementation and evaluation of such programs in practice.

Keywords: academic assessment, academic program planning, curriculum development, general education reform

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4347 Sensitivity Improvement of Optical Ring Resonator for Strain Analysis with the Direction of Strain Recognition Possibility

Authors: Tayebeh Sahraeibelverdi, Ahmad Shirazi Hadi Veladi, Mazdak Radmalekshah

Abstract:

Optical sensors became attractive due to preciseness, low power consumption, and intrinsic electromagnetic interference-free characteristic. Among the waveguide optical sensors, cavity-based ones attended for the high Q-factor. Micro ring resonators as a potential platform have been investigated for various applications as biosensors to pressure sensors thanks to their sensitive ring structure responding to any small change in the refractive index. Furthermore, these small micron size structures can come in an array, bringing the opportunity to have any of the resonance in a specific wavelength and be addressed in this way. Another exciting application is applying a strain to the ring and making them an optical strain gauge where the traditional ones are based on the piezoelectric material. Making them in arrays needs electrical wiring and about fifty times bigger in size. Any physical element that impacts the waveguide cross-section, Waveguide elastic-optic property change, or ring circumference can play a role. In comparison, ring size change has a larger effect than others. Here an engineered ring structure is investigated to study the strain effect on the ring resonance wavelength shift and its potential for more sensitive strain devices. At the same time, these devices can measure any strain by mounting on the surface of interest. The idea is to change the" O" shape ring to a "C" shape ring with a small opening starting from 2π/360 or one degree. We used the Mode solution of Lumbrical software to investigate the effect of changing the ring's opening and the shift induced by applied strain. The designed ring radius is a three Micron silicon on isolator ring which can be fabricated by standard complementary metal-oxide-semiconductor (CMOS) micromachining. The measured wavelength shifts from1-degree opening of the ring to a 6-degree opening have been investigated. Opening the ring for 1-degree affects the ring's quality factor from 3000 to 300, showing an order of magnitude Q-factor reduction. Assuming a strain making the ring-opening from 1 degree to 6 degrees, our simulation results showing negligible Q-factor reduction from 300 to 280. A ring resonator quality factor can reach up to 108 where an order of magnitude reduction is negligible. The resonance wavelength shift showed a blue shift and was obtained to be 1581, 1579,1578,1575nm for 1-, 2-, 4- and 6-degree ring-opening, respectively. This design can find the direction of the strain-induced by applying the opening on different parts of the ring. Moreover, by addressing the specified wavelength, we can precisely find the direction. We can open a significant opportunity to find cracks and any surface mechanical property very specifically and precisely. This idea can be implemented on polymer ring resonators while they can come with a flexible substrate and can be very sensitive to any strain making the two ends of the ring in the slit part come closer or further.

Keywords: optical ring resonator, strain gauge, strain sensor, surface mechanical property analysis

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4346 The Strategy of the International Organization for Migration in Dealing with the Phenomenon of Migration

Authors: Djehich Mohamed Yousri

Abstract:

Nowadays, migration has become a phenomenon that attracts the attention of researchers, countries, agencies, and national and international bodies. Wars and climate change, demographics, poverty, natural disasters, and epidemics are all threats that are contributing daily to forcing more people to migrate. There are those who resort to emigration because of the deteriorating political conditions in their country, others resort to emigration to improve their financial situation, and others emigrate from their country for fear of some penalties and judgments issued against them. In the field of migration, becoming a member of the United Nations as a "relevant organization" gives the United Nations a clear mandate on migration. Its primary goal is to facilitate the management of international migration in an orderly and humane manner. In order to achieve this goal, the organization adopts an international policy to meet the challenges posed in the field of migration. This paper attempts to study the structure of this international organization and its strategy in dealing with the phenomenon of international migration.

Keywords: international organization for migration, immigrants, immigrant rights, resettlement, migration organization strategy

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4345 A FE-Based Scheme for Computing Wave Interaction with Nonlinear Damage and Generation of Harmonics in Layered Composite Structures

Authors: R. K. Apalowo, D. Chronopoulos

Abstract:

A Finite Element (FE) based scheme is presented for quantifying guided wave interaction with Localised Nonlinear Structural Damage (LNSD) within structures of arbitrary layering and geometric complexity. The through-thickness mode-shape of the structure is obtained through a wave and finite element method. This is applied in a time domain FE simulation in order to generate time harmonic excitation for a specific wave mode. Interaction of the wave with LNSD within the system is computed through an element activation and deactivation iteration. The scheme is validated against experimental measurements and a WFE-FE methodology for calculating wave interaction with damage. Case studies for guided wave interaction with crack and delamination are presented to verify the robustness of the proposed method in classifying and identifying damage.

Keywords: layered structures, nonlinear ultrasound, wave interaction with nonlinear damage, wave finite element, finite element

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4344 Fire Risk Information Harmonization for Transboundary Fire Events between Portugal and Spain

Authors: Domingos Viegas, Miguel Almeida, Carmen Rocha, Ilda Novo, Yolanda Luna

Abstract:

Forest fires along the more than 1200km of the Spanish-Portuguese border are more and more frequent, currently achieving around 2000 fire events per year. Some of these events develop to large international wildfire requiring concerted operations based on shared information between the two countries. The fire event of Valencia de Alcantara (2003) causing several fatalities and more than 13000ha burnt, is a reference example of these international events. Currently, Portugal and Spain have a specific cross-border cooperation protocol on wildfires response for a strip of about 30km (15 km for each side). It is recognized by public authorities the successfulness of this collaboration however it is also assumed that this cooperation should include more functionalities such as the development of a common risk information system for transboundary fire events. Since Portuguese and Spanish authorities use different approaches to determine the fire risk indexes inputs and different methodologies to assess the fire risk, sometimes the conjoint firefighting operations are jeopardized since the information is not harmonized and the understanding of the situation by the civil protection agents from both countries is not unique. Thus, a methodology aiming the harmonization of the fire risk calculation and perception by Portuguese and Spanish Civil protection authorities is hereby presented. The final results are presented as well. The fire risk index used in this work is the Canadian Fire Weather Index (FWI), which is based on meteorological data. The FWI is limited on its application as it does not take into account other important factors with great effect on the fire appearance and development. The combination of these factors is very complex since, besides the meteorology, it addresses several parameters of different topics, namely: sociology, topography, vegetation and soil cover. Therefore, the meaning of FWI values is different from region to region, according the specific characteristics of each region. In this work, a methodology for FWI calibration based on the number of fire occurrences and on the burnt area in the transboundary regions of Portugal and Spain, in order to assess the fire risk based on calibrated FWI values, is proposed. As previously mentioned, the cooperative firefighting operations require a common perception of the information shared. Therefore, a common classification of the fire risk for the fire events occurred in the transboundary strip is proposed with the objective of harmonizing this type of information. This work is integrated in the ECHO project SpitFire - Spanish-Portuguese Meteorological Information System for Transboundary Operations in Forest Fires, which aims the development of a web platform for the sharing of information and supporting decision tools to be used in international fire events involving Portugal and Spain.

Keywords: data harmonization, FWI, international collaboration, transboundary wildfires

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4343 Healthcare Fire Disasters: Readiness, Response and Resilience Strategies: A Real-Time Experience of a Healthcare Organization of North India

Authors: Raman Sharma, Ashok Kumar, Vipin Koushal

Abstract:

Healthcare facilities are always seen as places of haven and protection for managing the external incidents, but the situation becomes more difficult and challenging when such facilities themselves are affected from internal hazards. Such internal hazards are arguably more disruptive than external incidents affecting vulnerable ones, as patients are always dependent on supportive measures and are neither in a position to respond to such crisis situation nor do they know how to respond. The situation becomes more arduous and exigent to manage if, in case critical care areas like Intensive Care Units (ICUs) and Operating Rooms (OR) are convoluted. And, due to these complexities of patients’ in-housed there, it becomes difficult to move such critically ill patients on immediate basis. Healthcare organisations use different types of electrical equipment, inflammable liquids, and medical gases often at a single point of use, hence, any sort of error can spark the fire. Even though healthcare facilities face many fire hazards, damage caused by smoke rather than flames is often more severe. Besides burns, smoke inhalation is primary cause of fatality in fire-related incidents. The greatest cause of illness and mortality in fire victims, particularly in enclosed places, appears to be the inhalation of fire smoke, which contains a complex mixture of gases in addition to carbon monoxide. Therefore, healthcare organizations are required to have a well-planned disaster mitigation strategy, proactive and well prepared manpower to cater all types of exigencies resulting from internal as well as external hazards. This case report delineates a true OR fire incident in Emergency Operation Theatre (OT) of a tertiary care multispecialty hospital and details the real life evidence of the challenges encountered by OR staff in preserving both life and property. No adverse event was reported during or after this fire commotion, yet, this case report aimed to congregate the lessons identified of the incident in a sequential and logical manner. Also, timely smoke evacuation and preventing the spread of smoke to adjoining patient care areas by opting appropriate measures, viz. compartmentation, pressurisation, dilution, ventilation, buoyancy, and airflow, helped to reduce smoke-related fatalities. Henceforth, precautionary measures may be implemented to mitigate such incidents. Careful coordination, continuous training, and fire drill exercises can improve the overall outcomes and minimize the possibility of these potentially fatal problems, thereby making a safer healthcare environment for every worker and patient.

Keywords: healthcare, fires, smoke, management, strategies

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4342 Scaling Strategy of a New Experimental Rig for Wheel-Rail Contact

Authors: Meysam Naeimi, Zili Li, Rolf Dollevoet

Abstract:

A new small–scale test rig developed for rolling contact fatigue (RCF) investigations in wheel–rail material. This paper presents the scaling strategy of the rig based on dimensional analysis and mechanical modelling. The new experimental rig is indeed a spinning frame structure with multiple wheel components over a fixed rail-track ring, capable of simulating continuous wheel-rail contact in a laboratory scale. This paper describes the dimensional design of the rig, to derive its overall scaling strategy and to determine the key elements’ specifications. Finite element (FE) modelling is used to simulate the mechanical behavior of the rig with two sample scale factors of 1/5 and 1/7. The results of FE models are compared with the actual railway system to observe the effectiveness of the chosen scales. The mechanical properties of the components and variables of the system are finally determined through the design process.

Keywords: new test rig, rolling contact fatigue, rail, small scale

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4341 The Geometry of Natural Formation: an Application of Geometrical Analysis for Complex Natural Order of Pomegranate

Authors: Anahita Aris

Abstract:

Geometry always plays a key role in natural structures, which can be a source of inspiration for architects and urban designers to create spaces. By understanding formative principles in nature, a variety of options can be provided that lead to freedom of formation. The main purpose of this paper is to analyze the geometrical order found in pomegranate to find formative principles explaining its complex structure. The point is how spherical arils of pomegranate pressed together inside the fruit and filled the space as they expand in the growing process, which made a self-organized system leads to the formation of each of the arils are unique in size, topology and shape. The main challenge of this paper would be using advanced architectural modeling techniques to discover these principles.

Keywords: advanced modeling techniques, architectural modeling, computational design, the geometry of natural formation, geometrical analysis, the natural order of pomegranate, voronoi diagrams

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4340 Conventional Synthesis and Characterization of Zirconium Molybdate, Nd2Zr3(MoO4)9

Authors: G. Çelik Gül, F. Kurtuluş

Abstract:

Rare earths containing complex metal oxides have drawn much attention due to physical, chemical and optical properties which make them feasible in so many areas such as non-linear optical materials and ion exchanger. We have researched a systematic study to obtain rare earth containing zirconium molybdate compound, characterization, investigation of crystal system and calculation of unit cell parameters.  After a successful synthesis of Nd2Zr3(MoO4)9 which is a member of rare earth metal containing complex oxides family, X-ray diffraction (XRD), High Score Plus/Rietveld refinement analysis, and Fourier Transform Infrared Spectroscopy (FTIR) were completed to determine the crystal structure. Morphological properties and elemental composition were determined by scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis. Thermal properties were observed via Thermogravimetric-differential thermal analysis (TG/DTA).

Keywords: Nd₂Zr₃(MoO₄)₉, powder x-ray diffraction, solid state synthesis, zirconium molybdates

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4339 Production of Low-Density Nanocellular Foam Based on PMMA/PEBAX Blends

Authors: Nigus Maregu Demewoz, Shu-Kai Yeh

Abstract:

Low-density nanocellular foam is a fascinating new-generation advanced material due to its mechanical strength and thermal insulation properties. In nanocellular foam, reducing the density increases the insulation ability. However, producing a nanocellular foam of densities less than 0.3 with a cell size of less than 100 nm is very challenging. In this study, poly (methyl methacrylate) (PMMA) was blended with Polyether block amide (PEBAX) to study the effects of PEBAX on the nanocellular foam structure of the PMMA matrix. We added 2 wt% of PEBAX in the PMMA matrix, and the PEBAX nanostructured domain size of 45 nm was well dispersed in the PMMA matrix. The foaming result produced a new generation special bouquet-like nanocellular foam of cell size less than 50 nm with a relative density of 0.24. Also, we were able to produce a nanocellular foam of a relative density of about 0.17. In addition to thermal insulation applications, bouquet-like nanocellular foam may be expected for filtration applications.

Keywords: nanocellular foam, low-density, cell size, relative density, PMMA/PEBAX

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4338 Evaluating Residual Mechanical and Physical Properties of Concrete at Elevated Temperatures

Authors: S. Hachemi, A. Ounis, S. Chabi

Abstract:

This paper presents the results of an experimental study on the effects of elevated temperature on compressive and flexural strength of Normal Strength Concrete (NSC), High Strength Concrete (HSC) and High Performance Concrete (HPC). In addition, the specimen mass and volume were measured before and after heating in order to determine the loss of mass and volume during the test. In terms of non-destructive measurement, ultrasonic pulse velocity test was proposed as a promising initial inspection method for fire damaged concrete structure. 100 Cube specimens for three grades of concrete were prepared and heated at a rate of 3°C/min up to different temperatures (150, 250, 400, 600, and 900°C). The results show a loss of compressive and flexural strength for all the concretes heated to temperature exceeding 400°C. The results also revealed that mass and density of the specimen significantly reduced with an increase in temperature.

Keywords: high temperature, compressive strength, mass loss, ultrasonic pulse velocity

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4337 Intended and Unintended Outcomes of Partnerships at the Local Level in Slovakia

Authors: Daniel Klimovský

Abstract:

Slovakia belongs to the most fragmented countries if one looks at its local government structure. The Slovak central governments implemented both broad devolution and fiscal decentralization some decades ago. However, neither territorial consolidation nor size categorization of local competences and powers has been implemented yet. Taking this fact into account, it is clear that the local governments are challenged not only by their citizens as customers but also by effectiveness as well as efficiency of delivered services. The paper is focused on behavior of the local governments in Slovakia and their approaches towards other local partners, including other local governments. Analysis of set of interviews shows that inter-municipal cooperation is the most common local partnership in Slovakia, but due to diversity of the local governments, this kind of cooperation leads to both intended and unintended outcomes. While in many cases the local governments are more efficient as well as effective in delivery of local services thanks to inter-municipal cooperation, there are many cases where inter-municipal cooperation fails, and it brings rather questionable or even negative outcomes.

Keywords: local governments, local partnerships, inter-municipal cooperation, delivery of local services

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4336 Classification of High Order Thinking Skills (HOTS)

Authors: Mohammed Alkiyumi

Abstract:

Educational systems are currently paying special attention to developing learners' higher thinking skills to develop the capabilities of human resources to deal with contemporary challenges. Although psychologists disagree about the concept of higher-order thinking skills and the skills they include, there is unlimited effort in designing them and building strategies for their implementation. The most important factor helping to develop these skills is their classification according to specific criteria, and the most important of these classifications is Bloom's classification, which is dominant in most educational systems at all levels. Previous classifications have many limitations, including the comprehensiveness of the skills they contain, the logical structure of their hierarchy, and classification criteria. Therefore, this article puts another step in this area by providing a new classification of higher-order thinking skills that includes five categories: the first response stage, transformative stage, application, reasoning stage, and the production stage with a logical justification for this classification, with some techniques to developing it among learners.

Keywords: high-order thinking skills, classification, teaching, education

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4335 Morphological Properties in Ndre Mjeda's Works

Authors: Shyhrete Morina

Abstract:

This paper deals with morphological features in Mjeda's works. To make such a distinction, these features will be compared to standard Albanian language, considering the linguistic structure in the morphological field, which represent an all-important segment of Albanian language. Therefore, the study will focus mainly on the description and construction of these paradigms, which will give a linguistic insight into the entire work of Mjeda as the author who wrote in the dialect of northwestern Geg. Therefore, we have tried to distinguish different parts of the author's language, as well as the distinctive features or even the similarities of these paradigms that arise in the literary work of Mjeda. By constructing the corpus of this phonetic and grammar segment from the whole of Mjeda's work, we have seen that in these fields has built a variety of grammar structures, which for the history of Albanian are of special importance, that in the full variant of the work, as far as we can investigate, we will point out in all the distinctive features. Therefore, our study aims to highlight the linguistic features, namely the author's deep knowledge toward the language, the authenticity of its use, and its mutual relationship with it.

Keywords: distinctive morpholgy, nouns, adjetives, pronouns, Albanian standard language

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4334 Flexible Polyaniline-Based Composite Films for High-Performance Super Capacitors

Authors: A. Khosrozadeh, M. A. Darabi, M. Xing, Q. Wang

Abstract:

Fabrication of a high-performance supercapacitor (SC) using a flexible cellulose-based composite film of polyaniline (PANI), reduced graphene oxide (RGO), and silver nanowires (AgNWs) is reported. The flexibility, high capacitive behaviour, and cyclic stability of the entire device make it a good candidate for wearable SCs. The results show that a capacitance as high as 73.4 F/g (1.6 F/cm2) at a discharge rate of 1.1 A/g is achieved by the device. In addition, the SC demonstrates a power density up to 468.8 W/kg and an energy density up to 5.1 wh/kg. The flexibility of the composite film is attributed to the binding effect of cellulose fibers as well as reinforcing effect of AgNWs. The excellent electrochemical performance of the device is found to be owing to the synergistic effect between PANI/RGO/AgNWs ternary in a cushiony cellulose matrix and porous structure of the composite.

Keywords: cellulose, polyaniline, reduced graphene oxide, silver, super capacitor

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4333 Cryotopic Macroporous Polymeric Matrices for Regenerative Medicine and Tissue Engineering Applications

Authors: Archana Sharma, Vijayashree Nayak, Ashok Kumar

Abstract:

Three-dimensional matrices were fabricated from blend of natural-natural polymers like carrageenan-gelatin and synthetic -natural polymers such as PEG- gelatin (PEG of different molecular weights (2,000 and 6,000) using two different crosslinkers; glutaraldehyde and EDC-NHS by cryogelation technique. Blends represented a feasible approach to design 3-D scaffolds with controllable mechanical, physical and biochemical properties without compromising biocompatibility and biodegradability. These matrices possessed interconnected porous structure, good mechanical strength, biodegradable nature, constant swelling kinetics, ability to withstand high temperature and visco-elastic behavior. Hemocompatibility of cryogel matrices was determined by coagulation assays and hemolytic activity assay which demonstrated that these cryogels have negligible effects on coagulation time and have excellent blood compatibility. In vitro biocompatibility (cell-matrix interaction) inferred good cell adhesion, proliferation, and secretion of ECM on matrices. These matrices provide a microenvironment for the growth, proliferation, differentiation and secretion of ECM of different cell types such as IMR-32, C2C12, Cos-7, rat bone marrow derived MSCs and human bone marrow MSCs. Hoechst 33342 and PI staining also confirmed that the cells were uniformly distributed, adhered and proliferated properly on the cryogel matrix. An ideal scaffold used for tissue engineering application should allow the cells to adhere, proliferate and maintain their functionality. Neurotransmitter analysis has been done which indicated that IMR-32 cells adhered, proliferated and secreted neurotransmitters when they interacted with these matrices which showed restoration of their functionality. The cell-matrix interaction up to molecular level was also evaluated so to check genotoxicity and protein expression profile which indicated that these cryogel matrices are non-genotoxic and maintained biofunctionality of cells growing on these matrices. All these cryogels, when implanted subcutaneously in balb/c mice, showed no adverse systemic or local toxicity effects at implantation site. There was no significant increase in inflammatory cell count has otherwise been observed after scaffold implantation. These cryogels are supermacroporous and this porous structure allows cell infiltration and proliferation of host cells. This showed the integration and presence of infiltrated cells into the cryogel implants. Histological analysis confirmed that the implanted cryogels do not have any adverse effect in spite of host immune system recognition at the site of implantation, on its surrounding tissues and other vital host organs. In vivo biocompatibility study after in vitro biocompatibility analysis has also concluded that these synthesized cryogels act as important biological substitutes, more adaptable and appropriate for transplantation. Thus, these cryogels showed their potential for soft tissue engineering applications.

Keywords: cryogelation, hemocompatibility, in vitro biocompatibility, in vivo biocompatibility, soft tissue engineering applications

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4332 Effect of Heat Treatment on the Corrosion Behavior of Stainless Steel

Authors: Altoumi Alndalusi

Abstract:

The work examines the aqueous corrosion behavior of grades of stain less steel which are used as corrosion resistant castings for applications such as valve and pump bodies. The corrosion behavior of steels in the as-cast condition has been examined using potentiostatic studies to illustrate the need for correct thermal treatment. A metallurgical examination and chemical analysis were carried out to establish the morphology of the steel structure. Heat treatment was carried out in order to compare damage in relation to microstructure. Optical and scanning electron microscopy examinations confirmed that the austenitic steels suffers from severe localized inter-dendritic pitting attack, while non homogenized castings highly alloyed duplex steels gave inferior corrosion resistance. Through the heat treatment conditions a significant of phase transformation of the duplex steel C were occurred (from ferrite to austenite and sigma plus carbides) and were gave reduction resistance.

Keywords: cast, corrosion, duplex stainless, heat treatment, material, steel

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4331 The Relationship between Fatigue Crack Growth and Residual Stress in Rails

Authors: F. Husem, M. E. Turan, Y. Sun, H. Ahlatci, I. Tozlu

Abstract:

Residual stress and fatigue crack growth rates are important to determine mechanical behavior of rails. This study aims to make relationship between residual stress and fatigue crack growth values in rails. For this purpose, three R260 quality rails (0.6-0.8% C, 0.6-1.25 Mn) were chosen. Residual stress of samples was measured by cutting method that is related in railway standard. Then samples were machined for fatigue crack growth test and analyze was completed according to the ASTM E647 standard which gives information about parameters of rails for this test. Microstructure characterizations were examined by Light Optic Microscope (LOM). The results showed that residual stress change with fatigue crack growth rate. The sample has highest residual stress exhibits highest crack growth rate and pearlitic structure can be seen clearly for all samples by microstructure analyze.

Keywords: residual stress, fatigue crack growth, R260, SEM, ASTM E647

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4330 A Study on Development Strategies of Marine Leisure Tourism Using AHP

Authors: Da-Hye Jang, Woo-Jeong Cho

Abstract:

Marine leisure tourism contributes greatly to the national economy in which the sea is located nearby and many countries are using marine tourism to create value added. The interest and investment of government and local governments on marine leisure tourism growing as a major trend of marine tourism is steadily increasing. But indiscriminate investment in marine leisure tourism such as duplicated business wastes limited resources. In other words, government and local governments need to select and concentrate on the goal they pursue by drawing priority on maritime leisure tourism policies. The purpose of this study is to analyze development strategies on supplier for marine leisure tourism and thus provide a comprehensive and rational framework for developing marine leisure tourism. In order to achieve the purpose, this study is to analyze priorities for each evaluation criterion of marine leisure tourism development policies using Analytic Hierarchy Process. In this study, a questionnaire was used as the survey tool and was developed based on the previous studies, government report, regional report, related thesis and literature for marine leisure tourism. The questionnaire was constructed by verifying the validity of contents from the expert group related to marine leisure tourism after conducting the first and second preliminary surveys. The AHP survey was conducted to experts (university professors, researchers, field specialists and related public officials) from April 6, 2018 to April 30, 2018 by visiting in person or e-mail. This study distributed 123 questionnaires and 68 valid questionnaires were used for data analysis. As a result, 4 factors with 12 detail strategies were analyzed using Excel. Extracted factors of development strategies of marine leisure tourism are consist of 4 factors such as infrastructure, popularization, law & system improvement and advancement. In conclusion, the results of the pairwise comparison of the four major factor on the first class were infrastructure, popularization, law & system improvement and advancement in order. Second, marine water front space maintenance had higher priority than marina facilities expansion and the establishment of marine leisure education center. Third, marine leisure safety·culture improvement had higher priority than strengthening experience·education program and the upkeep and open promotion event. Fourth, specialization·cluster of marine leisure tourism had higher priority than business support system of marine leisure tourism. Fifth, the revision of water-related leisure activities safety act had higher priority than an enactment of marine tourism promotion act and the foster of marina service industry. Finally, marine water front space maintenance was the most important development plan to boost marine leisure tourism.

Keywords: marine leisure tourism, marine leisure, marine tourism, analytic hierarchy process

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4329 Dual Ion-Crosslinking Human Keratin Based Bioink for 3D Bioprinting

Authors: Jae Seo Lee, Il Keun Kwon

Abstract:

In the last decades, keratin-based on natural extracts has considerably increased interest as a skin tissue regeneration. However, most parts of keratin had a limitation to 3D scaffolds due to low biological affinity and general low mechanical properties. To create a 3D structure, a facile bioink was designed with a photocurable crosslinking stage system using natural polymer-based human keratin. Keratin-based bioink enables the crosslinking more quickly through two types of photo and ion crosslinking for module engineering assembly. Rheological results showed that keratin-based bioink with high concentration possessed superior mechanical rigidity for 3D bioprinting. Different 3D geometrically constructs were successfully fabricated with optimal bioprinting parameters through the 3D printer with X-Y-Z controlled UV laser system. The presented study has offered a distinct advantage for 3D printing of keratin-based hydrogel into 3D complex-shaped biomimetic constructs. Thus, keratin-based bioink opens up new avenues in bioprinting to directly substitute tissue or organs.

Keywords: human keratin, hydrogel, ion-crosslinking, 3D bioprinting

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4328 Reduced Power Consumption by Randomization for DSI3

Authors: David Levy

Abstract:

The newly released Distributed System Interface 3 (DSI3) Bus Standard specification defines 3 modulation levels from which 16 valid symbols are coded. This structure creates power consumption variations depending on the transmitted data of a factor of more than 2 between minimum and maximum. The power generation unit has to consider therefore the worst case maximum consumption all the time and be built accordingly. This paper proposes a method to reduce both the average current consumption and worst case current consumption. The transmitter randomizes the data using several pseudo-random sequences. It then estimates the energy consumption of the generated frames and selects to transmit the one which consumes the least. The transmitter also prepends the index of the pseudo-random sequence, which is not randomized, to allow the receiver to recover the original data using the correct sequence. We show that in the case that the frame occupies most of the DSI3 synchronization period, we achieve average power consumption reduction by up to 13% and the worst case power consumption is reduced by 17.7%.

Keywords: DSI3, energy, power consumption, randomization

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4327 Thermoelectric Properties of Doped Polycrystalline Silicon Film

Authors: Li Long, Thomas Ortlepp

Abstract:

The transport properties of carriers in polycrystalline silicon film affect the performance of polycrystalline silicon-based devices. They depend strongly on the grain structure, grain boundary trap properties and doping concentration, which in turn are determined by the film deposition and processing conditions. Based on the properties of charge carriers, phonons, grain boundaries and their interactions, the thermoelectric properties of polycrystalline silicon are analyzed with the relaxation time approximation of the Boltz- mann transport equation. With this approach, thermal conductivity, electrical conductivity and Seebeck coefficient as a function of grain size, trap properties and doping concentration can be determined. Experiment on heavily doped polycrystalline silicon is carried out and measurement results are compared with the model.

Keywords: conductivity, polycrystalline silicon, relaxation time approximation, Seebeck coefficient, thermoelectric property

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4326 Prediction of the Thermodynamic Properties of Hydrocarbons Using Gaussian Process Regression

Authors: N. Alhazmi

Abstract:

Knowing the thermodynamics properties of hydrocarbons is vital when it comes to analyzing the related chemical reaction outcomes and understanding the reaction process, especially in terms of petrochemical industrial applications, combustions, and catalytic reactions. However, measuring the thermodynamics properties experimentally is time-consuming and costly. In this paper, Gaussian process regression (GPR) has been used to directly predict the main thermodynamic properties - standard enthalpy of formation, standard entropy, and heat capacity -for more than 360 cyclic and non-cyclic alkanes, alkenes, and alkynes. A simple workflow has been proposed that can be applied to directly predict the main properties of any hydrocarbon by knowing its descriptors and chemical structure and can be generalized to predict the main properties of any material. The model was evaluated by calculating the statistical error R², which was more than 0.9794 for all the predicted properties.

Keywords: thermodynamic, Gaussian process regression, hydrocarbons, regression, supervised learning, entropy, enthalpy, heat capacity

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4325 Characterization of Surface Microstructures on Bio-Based PLA Fabricated with Nano-Imprint Lithography

Authors: D. Bikiaris, M. Nerantzaki, I. Koliakou, A. Francone, N. Kehagias

Abstract:

In the present study, the formation of structures in poly(lactic acid) (PLA) has been investigated with respect to producing areas of regular, superficial features with dimensions comparable to those of cells or biological macromolecules. Nanoimprint lithography, a method of pattern replication in polymers, has been used for the production of features ranging from tens of micrometers, covering areas up to 1 cm², down to hundreds of nanometers. Both micro- and nano-structures were faithfully replicated. Potentially, PLA has wide uses within biomedical fields, from implantable medical devices, including screws and pins, to membrane applications, such as wound covers, and even as an injectable polymer for, for example, lipoatrophy. The possibility of fabricating structured PLA surfaces, with structures of the dimensions associated with cells or biological macro- molecules, is of interest in fields such as cellular engineering. Imprint-based technologies have demonstrated the ability to selectively imprint polymer films over large areas resulting in 3D imprints over flat, curved or pre-patterned surfaces. Here, we compare nano-patterned with nano-patterned by nanoimprint lithography (NIL) PLA film. A silicon nanostructured stamp (provided by Nanotypos company) having positive and negative protrusions was used to pattern PLA films by means of thermal NIL. The polymer film was heated from 40°C to 60°C above its Tg and embossed with a pressure of 60 bars for 3 min. The stamp and substrate were demolded at room temperature. Scanning electron microscope (SEM) images showed good replication fidelity of the replicated Si stamp. Contact-angle measurements suggested that positive microstructuring of the polymer (where features protrude from the polymer surface) produced a more hydrophilic surface than negative micro-structuring. The ability to structure the surface of the poly(lactic acid), allied to the polymer’s post-processing transparency and proven biocompatibility. Films produced in this were also shown to enhance the aligned attachment behavior and proliferation of Wharton’s Jelly Mesenchymal Stem cells, leading to the observed growth contact guidance. The bacterial attachment patterns of some bacteria, highlighted that the nano-patterned PLA structure can reduce the propensity for the bacteria to attach to the surface, with a greater bactericidal being demonstrated activity against the Staphylococcus aureus cells. These biocompatible, micro- and nanopatterned PLA surfaces could be useful for polymer– cell interaction experiments at dimensions at, or below, that of individual cells. Indeed, post-fabrication modification of the microstructured PLA surface, with materials such as collagen (which can further reduce the hydrophobicity of the surface), will extend the range of applications, possibly through the use of PLA’s inherent biodegradability. Further study is being undertaken to examine whether these structures promote cell growth on the polymer surface.

Keywords: poly(lactic acid), nano-imprint lithography, anti-bacterial properties, PLA

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4324 Numerical Analysis and Design of Dielectric to Plasmonic Waveguides Couplers

Authors: Emanuela Paranhos Lima, Vitaly Félix Rodríguez Esquerre

Abstract:

In this work, efficient directional coupler composed of dielectric waveguides and metallic film has been analyzed in details by simulations using finite element method (FEM). The structure consists of a step-index fiber with dielectric core, silica cladding, and a metal nanowire parallel to the core. The results show that an efficient conversion of optical dielectric modes to long range plasmonic is possible. Low insertion losses in conjunction with short coupling length and a broadband operation can be achieved under certain conditions. This kind of couplers has potential applications for the design of photonic integrated circuits for signal routing between dielectric/plasmonic waveguides, sensing, lithography, and optical storage systems. A high efficient focusing of light in a very small region can be obtained.

Keywords: directional coupler, finite element method, metallic nanowire, plasmonic, surface plasmon polariton, superfocusing

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4323 Investigation Of The Catalyst's Effect On Nickel Sulfide Thin Films

Authors: Randa Slatnia

Abstract:

In this study, the nanostructured stable phase identification elaborated by nickel nitrate hyxahydrate and thiourea compounds. After the preparation of the solution (Stirred mixture with methanol as solvent), a deposition of eight layers of this solution on a glass substrate and annealed at 300 °C for energy applications. The annealed sample was analyzed by X-ray Grazing incidence diffraction (GID) with a Bruker D8 Advance diffractometer using Cu Kα1 radiation at 40 kV and 40 mA (1600 W) and Scanning electron microscopy (Thermo Fisher environmental SEM). The results of XRD-GID analysis for the prepared sample showed the formation of an identified stable phase NiS2 and the XRD-GID pattern of the elaborated sample with eight layers prepared solution and annealed show wide and characteristic peaks of the NiS2 with cubic structure (ICDD card no. PDF 01-078-4702). The morphology of the NiS2 thin films confirmed by XRD-GID analysis was investigated by ESEM showed a surface with a uniform and homogeneous distribution nanostructure.

Keywords: nickel sulfide, thin films, XRD, ESEM

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4322 Sustainable Development Goals: The Effect of a Board Structure on the Sustainability Performance

Authors: V. Naciti, L. Pulejo, F. Cesaroni

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This study empirically analyzes whether the composition of the board of directors (BoD) enhances sustainability performance, in order to understand how the BoD contribute to the integration of Sustainable Development Goals (SDGs) in their businesses. Hypotheses are developed based on the agency theory and stakeholder theory. Using a system generalized method of the moment (SGMM) two-step estimator, with data from Sustainalytics and Compustat databases for 362 firms in six regions, we find that firms with more diversity on the board and a separation of chair and CEO roles have higher sustainability performance. Moreover, our findings provide that a higher number of independent directors is negatively associated with sustainability performance. This study contributes to the literature on corporate governance and the firm’s performance by demonstrating that the composition of the board of directors contributes to a better sustainability performance: by the implementation of a particular corporate governance mechanism, it is possible to integrate SDGs in the corporate strategy.

Keywords: sustainable development goals, corporate governance, board of directors, sustainability performance

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4321 Seismic Response of Braced Steel Frames with Shape Memory Alloy and Mega Bracing Systems

Authors: Mohamed Omar

Abstract:

Steel bracing members are widely used in steel structures to reduce lateral displacement and dissipate energy during earthquake motions. Concentric steel bracing provide an excellent approach for strengthening and stiffening steel buildings. Using these braces the designer can hardly adjust the stiffness together with ductility as needed because of buckling of braces in compression. In this study the use of SMA bracing and steel bracing (Mega) utilized in steel frames are investigated. The effectiveness of these two systems in rehabilitating a mid-rise eight-storey steel frames were examined using time-history nonlinear analysis utilizing Seismo-Struct software. Results show that both systems improve the strength and stiffness of the original structure but due to excellent behavior of SMA in nonlinear phase and under compressive forces this system shows much better performance than the rehabilitation system of Mega bracing.

Keywords: finite element analysis, seismic response, shapes memory alloy, steel frame, mega bracing

Procedia PDF Downloads 307
4320 Factors Affecting the Critical Understanding of the Strategies Which Children Use to Motivate Parents in the Family Buying Process: Case of British Bangladeshi Children in the UK

Authors: Salma Akter, Mohammad M. Haque, Lawrence Akwetey

Abstract:

An empirical research design will analyze different factors/predictors children use to influence their parents in the family buying decision process in the unexplored area of British Bangladeshi children in the United Kingdom. The proposed conceptual model of factors- buying decision making process will be tested by the Structure Equation Model. A structured Questionnaire and secondary sources will employ to collect data and analyse and measure the validity by Statistical tools (SPSS) and Microsoft Excel. The Contemporary research aims to use the deductive approach developing the research questions and testing the hypothesis to identify the impact of different strategies British Bangladeshi children used to influence their parents in the family buying decision which was overlooked in the previous research.

Keywords: British Bangladeshi children, buying decision process, children influence, influential factors

Procedia PDF Downloads 248