Search results for: soft clays
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1052

Search results for: soft clays

482 Electrochemistry of Metal Chalcogenides Semiconductor Materials; Theory and Practical Applications

Authors: Mahmoud Elrouby

Abstract:

Metal chalcogenide materials have wide spectrum of properties, for that these materials can be used in electronics, optics, magnetics, solar energy conversion, catalysis, passivation, ion sensing, batteries, and fuel cells. This work aims to, how can obtain these materials via electrochemical methods simply for further applications. The work regards in particular the systems relevant to the sulphur sub-group elements, i.e., sulphur, selenium, and tellurium. The role of electrochemistry in synthesis, development, and characterization of the metal chalcogenide materials and related devices is vital and important. Electrochemical methods as preparation tool offer the advantages of soft chemistry to access bulk, thin, nano film and epitaxial growth of a wide range of alloys and compounds, while as a characterization tool provides exceptional assistance in specifying the physicochemical properties of materials. Moreover, quite important applications and modern devices base their operation on electrochemical principles. Thereupon, our scope in the first place was to organize existing facts on the electrochemistry of metal chalcogenides regarding their synthesis, properties, and applications.

Keywords: electrodeposition, metal chacogenides, semiconductors, applications

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481 From Problem Space to Executional Architecture: The Development of a Simulator to Examine the Effect of Autonomy on Mainline Rail Capacity

Authors: Emily J. Morey, Kevin Galvin, Thomas Riley, R. Eddie Wilson

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The key challenges faced by integrating autonomous rail operations into the existing mainline railway environment have been identified through the understanding and framing of the problem space and stakeholder analysis. This was achieved through the completion of the first four steps of Soft Systems Methodology, where the problem space has been expressed via conceptual models. Having identified these challenges, we investigated one of them, namely capacity, via the use of models and simulation. This paper examines the approach used to move from the conceptual models to a simulation which can determine whether the integration of autonomous trains can plausibly increase capacity. Within this approach, we developed an architecture and converted logical models into physical resource models and associated design features which were used to build a simulator. From this simulator, we are able to analyse mixtures of legacy-autonomous operations and produce fundamental diagrams and trajectory plots to describe the dynamic behaviour of mixed mainline railway operations.

Keywords: autonomy, executable architecture, modelling and simulation, railway capacity

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480 The Proportion of Dysthymia Prevailing in Men and Women With Anxiety as Comorbidity

Authors: Yashvi Italiya

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Dysthymia (DD) is a much-overlooked soft mood disorder and mostly confused with other forms of chronic depression. This research paper gives a spotlight to the DD prevailing in men and women. It also focuses on one of the comorbidities of Dysthymia, i.e., Anxiety. The comorbidities, hurdles in diagnosis, the ubiquity of the disorder, and the relation of Anxiety and DD are briefly described. Gender was the main focus here because the researcher of this paper found it as a research gap while doing the literature review. The study was done through secondary data obtained primarily from a questionnaire having Alpha 0.891 reliability. T-test method of data analysis was used to test the hypotheses. The result shows that the researcher failed to accept alternative hypothesis 1 (M1 > M2), while the alternative hypothesis 2 (M1 > M2) was accepted. The ratio of DD in women (M1) is not higher than that of men (M2) (hypothesis 1). But, women are more anxious than men (hypothesis 2). It was found that comorbid Anxiety is more widespread in one gender. It further plays a significant role in mixing up the symptoms. It was concluded that the dividing line between Dysthymia and MDD is still unclear for an accurate diagnosis. There is an essential need for spreading knowledge concerning the differences between the symptoms of DD and MDD so that the actual disorder can be identified, and proper help can be received from/provided by professionals.

Keywords: anxiety, comorbidity, dysthymia, gender, MDD

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479 Phosphate Tailings in View of a Better Waste Disposal And/or Valorization: Case of Tunisian Phosphates Mines

Authors: Mouna Ettoumi, Jouini Marouen, Carmen Mihaela Neculita, Salah Bouhlel, Lucie Coudert, Mostafa Benzaazoua, Y. Taha

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In the context of sustainable development and circular economy, waste valorization is considered a promising alternative to overcome issues related to their disposal or elimination. The aim of this study is to evaluate the potential use of phosphate sludges (tailings) from the Kef Shfeir mine site (Gafsa, Tunisia) as an alternative material in the production of fired bricks. To do so, representative samples of raw phosphate treatment sludges were collected and characterized for their physical, chemical, mineralogical and environmental characteristics. Then, the raw materials were baked at different temperatures (900°C, 1000°C, and 1100°C) for bricks making. Afterward, fired bricks were characterized for their physical (particle size distribution, density, and plasticity), chemical (XRF and digestion), mineralogical (XRD) and mechanical (flexural strength) properties as well as for their environmental behavior (TCLP, SPLP, and CTEU-9) to ensure whether they meet the required construction standards. Results showed that the raw materials had low density (2.47g/cm 3), were non-plastic and were mainly composed of fluoroapatite (15.6%), calcite (23.1%) and clays (22.2% - mainly as heulandite, vermiculite and palygorskite). With respect to the environmental behavior, all metals (e.g., Pb, Zn, As, Cr, Ba, Cd) complied with the requirements set by the USEPA. In addition, fired bricks had varying porosity (9-13%), firing shrinking (5.2-7.5%), water absorption (12.5-17.2%) and flexural strength (3.86-13.4 MPa). Noteworthy, an improvement in the properties (porosity, firing shrinking, water absorption, and flexural strength) of manufactured fired bricks was observed with the increase of firing temperature from 900 to 1100°C. All the measured properties complied with the construction norms and requirements. Moreover, regardless of the firing temperature, the environmental behavior of metals obeyed the requirements of the USEPA standards. Finally, fired bricks could be produced at high temperatures (1000°C) based on 100% of phosphate sludge without any substitution or addition of either chemical agents or binders. This sustainable brick-making process could be a promising approach for the Phosphate Company to partially manage these wastes, which are considered “non-profitable” for the moment and preserve soils that are exploited presently.

Keywords: phosphate treatment sludge, mine waste, backed bricks, waste valorization

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478 Debris' Effect on Bearing Capacity of Defective Piles in Sand

Authors: A. M. Nasr, W. R. Azzam, K. E. Ebeed

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For bored piles, careful cleaning must be used to reduce the amount of material trapped in the drilled hole; otherwise, the debris' presence might cause the soft toe effect, which would affect the axial resistance. There isn't much comprehensive research on bored piles with debris. In order to investigate the behavior of a single pile, a pile composite foundation, a two pile group, a three pile group and a four pile group investigation conducts, forty-eight numerical tests in which the debris is simulated using foam rubber.1m pile diameter and 10m length with spacing 3D and depth of foundation 1m used in this study. It is found that the existence of debris causes a reduction of bearing capacity by 64.58% and 33.23% for single pile and pile composite foundation, respectively, 23.27% and 24.24% for the number of defective piles / total number of pile =1/2 and 1 respectively for two group pile, 10.23%, 19.42% and 28.47% for the number of defective piles / total number of pile =1/3,2/3 and 1 respectively for three group pile and, this reduction increase with the increase in a number of defective piles / a total number of piles and 7.1%, 13.32%,19.02% and 26.36 for the number of defective piles / total number of pile =1/4,2/4,3/4 and 1 respectively for four group pile and decreases with an increase of number of pile duo to interaction effect.

Keywords: debris, Foundation, defective, interaction, board pile

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477 A Hyperflexion Hallux Mallet Injury: A Case Report

Authors: Tan G. K. Y., Chew M. S. J., Sajeev S., Vellasamy A.

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Injuries of the extensor hallucis longus (EHL) tendon are a rare phenomenon, with most occurring due to lacerations or penetrating injuries. Closed traumatic ruptures of the EHL are described as “Mallet injuries of the toe”. These can be classified as bony or soft mallet injuries depending on the presence or absence of a fracture at the insertion site of the EHL tendon in the distal phalanx. We present a case of a 33-year-old woman who presented with a hyperflexion injury to the left big toe with an inability to extend the big toe. Ultrasound showed a complete rupture of the EHL tendon with retraction proximal to the hallucal interphalangeal joint of the big toe. The patient was treated through transarticular pinning and repair using the Arthrex Mini Bio-Suture Tak with a 2-0 fibre wire. Six months postoperatively, the patient had symmetrical EHL power and full range of motion of the toe. The lessons to be drawn from this case report are that isolated hallux mallet injuries are rare and can be easily missed in the absence of penetrating wounds. Patients who have such injuries should be investigated early with the appropriate imaging techniques, such as ultrasound or MRI, and treated surgically.

Keywords: hallux mallet, extensor hallucis longus tendon, extensor hallucis longus

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476 Teaching Entrepreneurship in Light of the Triple Bottom Line

Authors: Sherry Robinson, Hans Anton Stubberud

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Entrepreneurship can take many forms. Traditional entrepreneurs seek profits and growth for the businesses they start themselves. Intrapreneurs act entrepreneurially within a business they do not own. Social entrepreneurs have goals other than (but not excluding) profit and growth as they seek to solve social problems or protect the environment. This type of entrepreneur often focuses on the triple bottom line, which includes a concern for people and the planet as well as profit. Ecopreneurs in particular are driven by their desire to create and promote environmentally sustainable products and processes. All of these entrepreneurs need an entrepreneurial orientation in order to survive and thrive. The three most common elements of an entrepreneurial orientation are (1) creativity and innovation, (2) the willingness to take risks and (3) the proactiveness to put ideas into action. This study describes an interdisciplinary entrepreneurship course integrating topics regarding the triple bottom line with those relevant to an entrepreneurial orientation. The results show that students significantly increased their skill levels in many areas, including soft skills such as communicating and working in teams, as well as designing innovative products and taking calculated risk.

Keywords: creativity, entrepreneurship education, sustainability, triple bottom line

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475 Comparative Study of Equivalent Linear and Non-Linear Ground Response Analysis for Rapar District of Kutch, India

Authors: Kulin Dave, Kapil Mohan

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Earthquakes are considered to be the most destructive rapid-onset disasters human beings are exposed to. The amount of loss it brings in is sufficient to take careful considerations for designing of structures and facilities. Seismic Hazard Analysis is one such tool which can be used for earthquake resistant design. Ground Response Analysis is one of the most crucial and decisive steps for seismic hazard analysis. Rapar district of Kutch, Gujarat falls in Zone 5 of earthquake zone map of India and thus has high seismicity because of which it is selected for analysis. In total 8 bore-log data were studied at different locations in and around Rapar district. Different soil engineering properties were analyzed and relevant empirical correlations were used to calculate maximum shear modulus (Gmax) and shear wave velocity (Vs) for the soil layers. The soil was modeled using Pressure-Dependent Modified Kodner Zelasko (MKZ) model and the reference curve used for fitting was Seed and Idriss (1970) for sand and Darendeli (2001) for clay. Both Equivalent linear (EL), as well as Non-linear (NL) ground response analysis, has been carried out with Masing Hysteretic Re/Unloading formulation for comparison. Commercially available DEEPSOIL v. 7.0 software is used for this analysis. In this study an attempt is made to quantify ground response regarding generated acceleration time-history at top of the soil column, Response spectra calculation at 5 % damping and Fourier amplitude spectrum calculation. Moreover, the variation of Peak Ground Acceleration (PGA), Maximum Displacement, Maximum Strain (in %), Maximum Stress Ratio, Mobilized Shear Stress with depth is also calculated. From the study, PGA values estimated in rocky strata are nearly same as bedrock motion and marginal amplification is observed in sandy silt and silty clays by both analyses. The NL analysis gives conservative results of maximum displacement as compared to EL analysis. Maximum strain predicted by both studies is very close to each other. And overall NL analysis is more efficient and realistic because it follows the actual hyperbolic stress-strain relationship, considers stiffness degradation and mobilizes stresses generated due to pore water pressure.

Keywords: DEEPSOIL v 7.0, ground response analysis, pressure-dependent modified Kodner Zelasko model, MKZ model, response spectra, shear wave velocity

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474 Synthesis and Characterization of Novel Hollow Silica Particle through DODAB Vesicle Templating

Authors: Eun Ju Park, Wendy Rusli, He Tao, Alexander M. Van Herk, Sanggu Kim

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Hollow micro-/nano- structured materials have proven to be promising in wide range of applications, such as catalysis, drug delivery and controlled release, biotechnology, and personal and consumer care. Hollow sphere structures can be obtained through various templating approaches; colloid templates, emulsion templates, multi-surfactant templates, and single crystal templates. Vesicles are generally the self-directed assemblies of amphiphilic molecules including cationic, anionic, and cationic surfactants in aqueous solutions. The directed silica capsule formations were performed at the surface of dioctadecyldimethylammoniumbromide(DODAB) bilayer vesicles as soft template. The size of DODAB bilayer vesicles could be tuned by extrusion of a preheated dispersion of DODAB. The synthesized hollow silica particles were characterized by conventional TEM, cryo-TEM and SEM to determine the morphology and structure of particles and dynamic light scattering (DLS) method to measure the particle size and particle size distribution.

Keywords: characterization, DODAB, hollow silica particle, synthesis, vesicle

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473 Reimagining Writing as a Healing Art: A Case Study on Emotional Intelligence

Authors: Shawnrece Campbell

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Emotional intelligence as an essential job skill is growing in popularity among human resource professionals and hiring managers. Companies value those who have high emotional intelligence because of their personal competences (self-awareness, self-regulation, motivation) and social competences (empathy, social skills). In implementing any training system to teach emotional intelligence, the best methodologies for acquiring and/or improving these competences should be taken into consideration. This study focuses on how students perceived the art of writing as a tool for self-improvement. During this session, participants will engage in a brief activity designed to help students develop emotional intelligence. As a part of the discussion, participants will learn the results of a junior-level literary seminar conducted to better understand students’ thoughts and views about the effectiveness of writing as a tool for emotional healing. An analysis of qualitative textual data is presented. The outcomes indicated that students found using writing as a tool for emotional intelligence development as highly effective. The findings also revealed that students have positive perceptions of using writing as a self-healing art that leads to increased emotional intelligence and believe that writing courses of this nature enhance students’ appreciation of the value of the liberal arts.

Keywords: emotional intelligence quotient, healing, soft skills, writing

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472 Promotion of Healthy Food Choices in School Children through Nutrition Education

Authors: Vinti Davar

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Introduction: Childhood overweight increases the risk for certain medical and psychological conditions. Millions of school-age children worldwide are affected by serious yet easily treatable and preventable illnesses that inhibit their ability to learn. Healthier children stay in school longer, attend more regularly, learn more and become healthier and more productive adults. Schools are an important setting for nutrition education because one can reach most children, teachers and parents. These years offer a key window for shaping their lifetime habits, which have an impact on their health throughout life. Against this background, an attempt was made to impart nutrition education to school children in Haryana state of India to promote healthy food choices and assess the effectiveness of this program. Methodology: This study was completed in two phases. During the first phase, pre-intervention anthropometric and dietary survey was conducted; the teaching materials for nutrition intervention program were developed and tested; and the questionnaire was validated. In the second phase, an intervention was implemented in two schools of Kurukshetra, Haryana for six months by personal visits once a week. A total of 350 children in the age group of 6-12 years were selected. Out of these, 279 children, 153 boys and 126 girls completed the study. The subjects were divided into four groups namely: underweight, normal, overweight and obese based on body mass index-for-age categories. A power point colorful presentation to improve the quality of tiffin, snacks and meals emphasizing inclusion of all food groups especially vegetables every day and fruits at least 3-4 days per week was used. An extra 20 minutes of aerobic exercise daily was likewise organized and a healthy school environment created. Provision of clean drinking water by school authorities was ensured. Selling of soft drinks and energy-dense snacks in the school canteen as well as advertisements about soft drink and snacks on the school walls were banned. Post intervention, anthropometric indices and food selections were reassessed. Results: The results of this study reiterate the critical role of nutrition education and promotion in improving the healthier food choices by school children. It was observed that normal, overweight and obese children participating in nutrition education intervention program significantly (p≤0.05) increased their daily seasonal fruit and vegetable consumption. Fat and oil consumption was significantly reduced by overweight and obese subjects. Fast food intake was controlled by obese children. The nutrition knowledge of school children significantly improved (p≤0.05) from pre to post intervention. A highly significant increase (p≤0.00) was noted in the nutrition attitude score after intervention in all four groups. Conclusion: This study has shown that a well-planned nutrition education program could improve nutrition knowledge and promote positive changes in healthy food choices. A nutrition program inculcates wholesome eating and active life style habits in children and adolescents that could not only prevent them from chronic diseases and early death but also reduce healthcare cost and enhance the quality of life of citizens and thereby nations.

Keywords: children, eating habits healthy food, obesity, school going, fast foods

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471 Realization of Wearable Inertial Measurement Units-Sensor-Fusion Harness to Control Therapeutic Smartphone Applications

Authors: Svilen Dimitrov, Manthan Pancholi, Norbert Schmitz, Didier Stricker

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This paper presents the end-to-end development of a wearable motion sensing harness consisting of computational unit and four inertial measurement units to control three smartphone therapeutic games for children. The inertial data is processed in real time to obtain lower body motion information like knee raises, feet taps and squads. By providing a Wi-Fi connection interface the sensor harness acts wireless remote control for smartphone applications. By performing various lower body movements the users provoke corresponding game state changes. In contrary to the current similar offers, like Nintendo Wii Remote, Xbox Kinect and Playstation Move, this product, consisting of the sensor harness and the applications on top of it, are fully wearable, which means they do not rely on the user to be bound to concrete soft- or hardwareequipped space.

Keywords: wearable harness, inertial measurement units, smartphone therapeutic games, motion tracking, lower-body activity monitoring

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470 Seismic Assessment of Old Existing RC Buildings with Masonry Infill in Madinah as Per ASCE

Authors: Tarek M. Alguhane, Ayman H. Khalil, Nour M. Fayed, Ayman M. Ismail

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An existing RC building in Madinah is seismically evaluated with and without infill wall. Four model systems have been considered i. e. model I (no infill), model IIA (strut infill-update from field test), model IIB (strut infill- ASCE/SEI 41) and model IIC (strut infill-Soft storey-ASCE/SEI 41). Three dimensional pushover analyses have been carried out using SAP 2000 software incorporating inelastic material behavior for concrete, steel and infill walls. Infill wall has been modeled as equivalent strut according to suggested equation matching field test measurements and to the ASCE/SEI 41 equation. The effect of building modeling on the performance point as well as capacity and demand spectra due to EQ design spectrum function in Madinah area has been investigated. The response modification factor (R) for the 5 story RC building is evaluated from capacity and demand spectra (ATC-40) for the studied models. The results are summarized and discussed.

Keywords: infill wall, pushover analysis, response modification factor, seismic assessment

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469 Competition for Talent: Retaining Graduates in the Euregio Meuse-Rhine

Authors: Julia Reinold, Inge Hooijen, Christoph Meng, Melissa Siegel

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This paper investigates whether or not students intend to stay in the Euregio Meuse-Rhine (EMR) after graduation taking into account the role of hard and soft locational factors, social factors as well as demographic aspects in shaping their mobility preferences. Since graduates are considered a convenient source of human capital in today’s knowledge based economy, it is crucial to understand what drives their mobility intentions in order to retain larger numbers of graduates. This is particularly true for peripheral regions, which need to compete with assumed more attractive economic centres. This paper adds a euregional perspective to the existing literature on graduate migration. Using survey data from 2015 from five higher education institutions in the EMR, this paper finds that mobility intentions are determined by students’ perceptions of the quality of life, openness and career opportunities in the euroregion. In addition, distance to the partner and other social ties such as family and friends influence migration intentions.

Keywords: Euroregion, graduate migration, highly skilled migration, human capital

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468 The Impact of the Media in the Implementation of Qatar’s Foreign Policy on the Public Opinion of the People of the Middle East (2011-2023)

Authors: Negar Vkilbashi, Hassan Kabiri

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Modern diplomacy, in its general form, refers to the people and not the governments, and diplomacy tactics are more addressed to the people than to the governments. Media diplomacy and cyber diplomacy are also one of the sub-branches of public diplomacy and, in fact, the role of media in the process of influencing public opinion and directing foreign policy. Mass media, including written, radio and television, theater, satellite, internet, and news agencies, transmit information and demands. What the Qatari government tried to implement in the countries of the region during the Arab Spring and after was through its important media, Al Jazeera. The embargo on Qatar began in 2017, when Saudi Arabia, the United Arab Emirates, Bahrain, and Egypt imposed a land, sea, and air blockade against the country. The media tool constitutes the cornerstone of soft power in the field of foreign policy, which Qatari leaders have consistently resorted to over the past two decades. Undoubtedly, the role it played in covering the events of the Arab Spring has created geopolitical tensions. The United Arab Emirates and other neighboring countries sometimes criticize Al Jazeera for providing a platform for the Muslim Brotherhood, Hamas, and other Islamists to promote their ideology. In 2011, at the same time as the Arab Spring, Al Jazeera reached the peak of its popularity. Al Jazeera's live coverage of protests in Tunisia, Egypt, Yemen, Libya, and Syria helped create a unified narrative of the Arab Spring, with audiences tuning in every Friday to watch simultaneous protests across the Middle East. Al Jazeera operates in three groups: First, it is a powerful base in the hands of the government so that it can direct and influence Arab public opinion. Therefore, this network has been able to benefit from the unlimited financial support of the Qatar government to promote its desired policies and culture. Second, it has provided an attractive platform for politicians and scientific and intellectual elites, thus attracting their support and defense from the government and its rulers. Third, during the last years of Prince Hamad's reign, the Al Jazeera network formed a deterrent weapon to counter the media and political struggle campaigns. The importance of the research is that this network covers a wide range of people in the Middle East and, therefore, has a high influence on the decision-making of countries. On the other hand, Al Jazeera is influential as a tool of public diplomacy and soft power in Qatar's foreign policy, and by studying it, the results of its effectiveness in the past years can be examined. Using a qualitative method, this research analyzes the impact of the media on the implementation of Qatar's foreign policy on the public opinion of the people of the Middle East. Data collection has been done by the secondary method, that is, reading related books, magazine articles, newspaper reports and articles, and analytical reports of think tanks. The most important findings of the research are that Al Jazeera plays an important role in Qatar's foreign policy in Qatar's public diplomacy. So that, in 2011, 2017 and 2023, it played an important role in Qatar's foreign policy in various crises. Also, the people of Arab countries use Al-Jazeera as their first reference.

Keywords: Al Jazeera, Qatar, media, diplomacy

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467 Effect of Al Contents on Magnetic Domains of {100} Grains in Electrical Steels

Authors: Hyunseo Choi, Jaewan Hong, Seil Lee, Yang Mo Koo

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Non-oriented (NO) electrical steel is one of the most important soft magnetic materials for rotating machines. Si has usually been added to electrical steels to reduce eddy current loss by increasing the electrical resistivity. Si content more than 3.5 wt% causes cracks during cold rolling due to increase of brittleness. Al also increases the electrical resistivity of the materials as much as Si. In addition, cold workability of Fe-Al is better than Fe-Si, so that Al can be added up to 6.0 wt%. However, the effect of Al contents on magnetic properties of electrical steels has not been studied in detail. Magnetic domains of {100} grains in electrical steels, ranging from 1.85 to 6.54 wt% Al, were observed by magneto-optic Kerr microscopy. Furthermore, the correlation of magnetic domains with magnetic properties was investigated. As Al contents increased, the magnetic domain size of {100} grains decreased due to lowered domain wall energy. Reorganization of magnetic domain structure became more complex as domain size decreased. Therefore, the addition of Al to electrical steel caused hysteresis loss to increase. Anomalous loss decreased and saturated after 4.68% Al.

Keywords: electrical steel, magnetic domain structure, Al addition, core loss, rearrangement of domains

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466 Comparison of Meshing Stiffness of Altered Tooth Sum Spur Gear Tooth with Different Pressure Angles

Authors: H. K. Sachidananda, K. Raghunandana, B. Shivamurthy

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The estimation of gear tooth stiffness is important for finding the load distribution between the gear teeth when two consecutive sets of teeth are in contact. Based on dynamic model a C-program has been developed to compute mesh stiffness. By using this program position dependent mesh stiffness of spur gear tooth for various profile shifts have been computed for a fixed center distance and altering tooth-sum gearing (100 by ± 4%). It is found that the C-program using dynamic model is one of the rapid soft computing technique which helps in design of gears. The mesh tooth stiffness along the path of contact is studied for both 20° and 25° pressure angle gears at various profile shifts. Better tooth stiffness is noticed in case of negative alteration tooth-sum gears compared to standard and positive alteration tooth-sum gears. Also, in case of negative alteration tooth-sum gearing better mesh stiffness is noticed in 20° pressure angle when compared to 25°.

Keywords: altered tooth-sum gearing, bending fatigue, mesh stiffness, spur gear

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465 A New Approach towards the Development of Next Generation CNC

Authors: Yusri Yusof, Kamran Latif

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Computer Numeric Control (CNC) machine has been widely used in the industries since its inception. Currently, in CNC technology has been used for various operations like milling, drilling, packing and welding etc. with the rapid growth in the manufacturing world the demand of flexibility in the CNC machines has rapidly increased. Previously, the commercial CNC failed to provide flexibility because its structure was of closed nature that does not provide access to the inner features of CNC. Also CNC’s operating ISO data interface model was found to be limited. Therefore, to overcome that problem, Open Architecture Control (OAC) technology and STEP-NC data interface model are introduced. At present the Personal Computer (PC) has been the best platform for the development of open-CNC systems. In this paper, both ISO data interface model interpretation, its verification and execution has been highlighted with the introduction of the new techniques. The proposed is composed of ISO data interpretation, 3D simulation and machine motion control modules. The system is tested on an old 3 axis CNC milling machine. The results are found to be satisfactory in performance. This implementation has successfully enabled sustainable manufacturing environment.

Keywords: CNC, ISO 6983, ISO 14649, LabVIEW, open architecture control, reconfigurable manufacturing systems, sustainable manufacturing, Soft-CNC

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464 Physical and Mechanical Phenomena Associated with Rock Failure in Brazilian Disc Specimens

Authors: Hamid Reza Nejati, Amin Nazerigivi, Ahmad Reza Sayadi

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Failure mechanism of rocks is one of the fundamental aspects to study rock engineering stability. Rock is a material that contains flaws, initial damage, micro-cracks, etc. Failure of rock structure is largely due to tensile stress and was influenced by various parameters. In the present study, the effect of brittleness and loading rate on the physical and mechanical phenomena produced in rock during loading sequences is considered. For this purpose, Acoustic Emission (AE) technique is used to monitor fracturing process of three rock types (onyx marble, sandstone and soft limestone) with different brittleness and sandstone samples under different loading rate. The results of experimental tests revealed that brittleness and loading rate have a significant effect on the mode and number of induced fracture in rocks. An increase in rock brittleness increases the frequency of induced cracks, and the number of tensile fracture decreases when loading rate increases.

Keywords: brittleness, loading rate, acoustic emission, tensile fracture, shear fracture

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463 3D Numerical Analysis of Stone Columns Reinforced with Horizontal and Vertical Geosynthetic Materials

Authors: R. Ziaie Moayed, A. Khalili

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Improvement and reinforcement of soils with poor strength and engineering properties for constructing low height structures or structures such as liquid storage tanks, bridge columns, and heavy structures have necessitated applying particular techniques. Stone columns are among the well-known methods applied in such soils. This method provides an economically justified way for improving engineering properties of soft clay and loose sandy soils. Stone column implementation in these soils increases their bearing capacity and reduces the settlement of foundation build on them. In the present study, the finite difference based FLAC3D software was used to investigate the performance and effect of soil reinforcement through stone columns without lining and those with geosynthetic lining with different levels of stiffness in horizontal and vertical modes in clayey soils. The results showed that soil improvement using stone columns with lining in vertical and horizontal modes results in improvement of bearing capacity and foundation settlement.

Keywords: bearing capacity, FLAC3D, geosynthetic, settlement, stone column

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462 A Computational Framework for Load Mediated Patellar Ligaments Damage at the Tropocollagen Level

Authors: Fadi Al Khatib, Raouf Mbarki, Malek Adouni

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In various sport and recreational activities, the patellofemoral joint undergoes large forces and moments while accommodating the significant knee joint movement. In doing so, this joint is commonly the source of anterior knee pain related to instability in normal patellar tracking and excessive pressure syndrome. One well-observed explanation of the instability of the normal patellar tracking is the patellofemoral ligaments and patellar tendon damage. Improved knowledge of the damage mechanism mediating ligaments and tendon injuries can be a great help not only in rehabilitation and prevention procedures but also in the design of better reconstruction systems in the management of knee joint disorders. This damage mechanism, specifically due to excessive mechanical loading, has been linked to the micro level of the fibred structure precisely to the tropocollagen molecules and their connection density. We argue defining a clear frame starting from the bottom (micro level) to up (macro level) in the hierarchies of the soft tissue may elucidate the essential underpinning on the state of the ligaments damage. To do so, in this study a multiscale fibril reinforced hyper elastoplastic Finite Element model that accounts for the synergy between molecular and continuum syntheses was developed to determine the short-term stresses/strains patellofemoral ligaments and tendon response. The plasticity of the proposed model is associated only with the uniaxial deformation of the collagen fibril. The yield strength of the fibril is a function of the cross-link density between tropocollagen molecules, defined here by a density function. This function obtained through a Coarse-graining procedure linking nanoscale collagen features and the tissue level materials properties using molecular dynamics simulations. The hierarchies of the soft tissues were implemented using the rule of mixtures. Thereafter, the model was calibrated using a statistical calibration procedure. The model then implemented into a real structure of patellofemoral ligaments and patellar tendon (OpenKnee) and simulated under realistic loading conditions. With the calibrated material parameters the calculated axial stress lies well with the experimental measurement with a coefficient of determination (R2) equal to 0.91 and 0.92 for the patellofemoral ligaments and the patellar tendon respectively. The ‘best’ prediction of the yielding strength and strain as compared with the reported experimental data yielded when the cross-link density between the tropocollagen molecule of the fibril equal to 5.5 ± 0.5 (patellofemoral ligaments) and 12 (patellar tendon). Damage initiation of the patellofemoral ligaments was located at the femoral insertions while the damage of the patellar tendon happened in the middle of the structure. These predicted finding showed a meaningful correlation between the cross-link density of the tropocollagen molecules and the stiffness of the connective tissues of the extensor mechanism. Also, damage initiation and propagation were documented with this model, which were in satisfactory agreement with earlier observation. To the best of our knowledge, this is the first attempt to model ligaments from the bottom up, predicted depending to the tropocollagen cross-link density. This approach appears more meaningful towards a realistic simulation of a damaging process or repair attempt compared with certain published studies.

Keywords: tropocollagen, multiscale model, fibrils, knee ligaments

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461 Piezosurgery in Periodontics and Oral Implantology

Authors: Neelesh Papineni

Abstract:

Aim: Piezosurgery is a relatively new technique for osteotomy and osteoplasty that uses ultrasonic vibration. The conventional method of treating periodontal cases are by conventional surgeries. However, in this advancing field the use of motor-driven instruments is being considered less invasive. Out of these motor-driven instruments, piezo-electric device has been introduced to the field of periodontics and oral implantology. This article discusses about the wide range of application of piezo-electric device in periodontology, its advantages over conventional surgical therapies and other motor-driven instruments. Results: Piezo- electric has shown better results in aspect of osteotomy, osteoplasty, implants, and any procedure which includes conserving the bone. Also piezo-electric does not cause any kind of damage to the surrounding soft tissue and eliminates the risk of bone necrosis which is a risk factor in other motor driven instruments. Conclusion: In this era of modern dentistry , a successful periodontal and implant surgery requires a sound osseous support. This review gives a pictorial representation about the wide range of application of piezo-electric device in periodontology.

Keywords: piezo-electric, osteotomy, osteoplasty, implantology

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460 Superoxide Dismutase Activity of Male Rats after Administration of Extract and Nanoparticle of Ginger Torch Flower

Authors: Tresna Lestari, Tita Nofianti, Ade Yeni Aprilia, Lilis Tuslinah, Ruswanto Ruswanto

Abstract:

Nanoparticle formulation is often used to improve drug absorptivity, thus increasing the sharpness of the action. Ginger torch flower extract was formulated into nanoparticle form using poloxamer 1, 3 and 5%. The nanoparticle was then characterized by its particle size, polydispersity index, zeta potential, entrapment efficiency and morphological form by SEM. The result shows that nanoparticle formulations have particle size 134.7-193.1 nm, polydispersity index less than 0.5 for all formulations, zeta potential -41.0 - (-24.3) mV and entrapment efficiency 89.93-97.99 against flavonoid content with a soft surface and spherical form of particles. Methanolic extract of ginger torch flower could enhance superoxide dismutase activity by 1,3183 U/mL in male rats. Nanoparticle formulation of ginger torch extract is expected to increase the capability of the drug to enhance superoxide dismutase activity.

Keywords: superoxide dismutase, ginger torch flower, nanoparticle, poloxamer

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459 Higher-Level Return to Female Karate Competition Following Multiple Patella Dislocations

Authors: A. Maso, C. Bellissimo, G. Facchinetti, N. Milani, D. Panzin, D. Pogliana, L. Garlaschelli, L. Rivaroli, S. Rivaroli, M. Zurek, J. Konin

Abstract:

15 year-old female karate athlete experienced two unilateral patella dislocations: one contact and one non-contact. This challenged her from competing as planned at the regional and national competitions as a result of her inability to perform at a high level. Despite these injuries and other complicated factors, she was able to modify her training timeline and successfully perform, winning third at the National Cup. Initial pain numeric rating scale 8/10 during karate training isometric figures, taking the stairs, long walking, a positive rasp test, palpation pain on the lateral patella joint 9/10, pain performing open kinetic chain 0°-45° and close kinetic chain 30°-90°, tensor fascia lata, vastus lateralis, psoas muscles retraction/stiffness. Foot hyper pronation, internally rotated femur, and knee flexion 15° were the postural findings. Exercise prescription for three days/week for three weeks to include exercise-based rehabilitation and soft tissue mobilization with massage and foam rolling. After three weeks, the pain was improved during activity daily living 5/10, and soft tissue stiffness decreased. An additional four weeks of exercise-based rehabilitation was continued. At this time, axial x-rays and TA-GT TAC were taken, and an orthopaedic medical check was recommended to continue conservative treatment. At week seven, she performed 2/4 karate position technique without pain and 2/4 with pain. An isokinetic test was performed at week 12, demonstrating a 10% strength deficit and 6% resistance deficit both to the left hamstrings. Moreover, an 8% strength and resistance surplus to the left quadriceps was found. No pain was present during activity, daily living and sports activity, allowing a return to play training to begin. A plan for the return to play framework collaborated with her trainer, her father, a physiotherapist, a sports scientist, an osteopath, and a nutritionist. Within 4 and 5 months, both non-athlete and athlete movement quality analysis tests were performed. The plan agreed to establish a return to play goal of 7 months and the highest level return to competition goal of 9 months from the start of rehabilitation. This included three days/week of training and repeated testing of movement quality before return to competition with detectable improvements from 77% to 93%. Beginning goals of the rehabilitation plan included the importance of a team approach. The patient’s father and trainer were important to collaborate with to assure a safe and timely return to competition. The possibility of achieving the goals was strongly related to orthopaedic decision-making and progress during the first weeks of rehabilitation. Without complications or setbacks, the patient can successfully return to her highest level of competition. The patient returned to participation after five months of rehabilitation and training, and then she returned to competition at the national level in nine months. The successful return was the result of a team approach and a compliant patient with clear goals.

Keywords: karate, knee, performance, rehabilitation

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458 Compact Low Loss Design of SOI 1x2 Y-Branch Optical Power Splitter with S-Bend Waveguide and Study on the Variation of Transmitted Power with Various Waveguide Parameters

Authors: Nagaraju Pendam, C. P. Vardhani

Abstract:

A simple technology–compatible design of silicon-on-insulator based 1×2 optical power splitter is proposed. For developing large area Opto-electronic Silicon-on-Insulator (SOI) devices, the power splitter is a key passive device. The SOI rib- waveguide dimensions (height, width, and etching depth, refractive indices, length of waveguide) leading simultaneously to single mode propagation. In this paper a low loss optical power splitter is designed by using R Soft cad tool and simulated by Beam propagation method, here s-bend waveguides proposed. We concentrate changing the refractive index difference, branching angle, width of the waveguide, free space wavelength of the waveguide and observing transmitted power, effective refractive index in the designed waveguide, and choosing the best simulated results to be fabricated on silicon-on insulator platform. In this design 1550 nm free spacing are used.

Keywords: beam propagation method, insertion loss, optical power splitter, rib waveguide, transmitted power

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457 Optimal Load Factors for Seismic Design of Buildings

Authors: Juan Bojórquez, Sonia E. Ruiz, Edén Bojórquez, David de León Escobedo

Abstract:

A life-cycle optimization procedure to establish the best load factors combinations for seismic design of buildings, is proposed. The expected cost of damage from future earthquakes within the life of the structure is estimated, and realistic cost functions are assumed. The functions include: Repair cost, cost of contents damage, cost associated with loss of life, cost of injuries and economic loss. The loads considered are dead, live and earthquake load. The study is performed for reinforced concrete buildings located in Mexico City. The buildings are modeled as multiple-degree-of-freedom frame structures. The parameter selected to measure the structural damage is the maximum inter-story drift. The structural models are subjected to 31 soft-soil ground motions recorded in the Lake Zone of Mexico City. In order to obtain the annual structural failure rates, a numerical integration method is applied.

Keywords: load factors, life-cycle analysis, seismic design, reinforced concrete buildings

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456 The Nation as Brand: Postcolonial Construction of National Identity in Late 20th/21st Century Qatar

Authors: Ryunhye Kim

Abstract:

Despite its relatively short history as an independent state, Qatar has emerged as a highly regarded Gulf state and global power. Since its independence in September 1971, the state has employed deliberate policy initiatives designed to put Qatar on the map and distinguish it from other Gulf states. Because Qatar and its neighbors are resource-poor apart from energy, whoever is first to introduce a unique aspect of branding not only takes the lead but assumes what is often an insurmountable advantage. This study examines three specific modes of branding undertaken by Qatar: (1) energy policies to utilize its natural gas to become a dominant supplier; (2) the deliberate construction of a distinct cultural brand utilizing sports, architecture, museums, and media; and (3) ‘niche diplomacy’ to serve as a mediator in regional and intra-national conflicts, especially as interlocutor between the United States and Arab regimes and Muslim groups. Gleaning data from a range of sources, this study analyzes the effectiveness and significance of Qatar’s place branding on the global stage, as well as potential disadvantages and limits in this branding, including problems encountered before and after the ‘Qatar crisis.’

Keywords: national branding, national-identity, Qatar, soft-power

Procedia PDF Downloads 148
455 Production of Keratinase and Its Insilico Characterization

Authors: Akshita Bhardwaj

Abstract:

Keratinase is an enzyme obtained from extracellular sources that is involved in biodegradation of keratin. It is a member of a group of proteases that can break down keratin into amino acids. Keratinases are produced only in the presence of substrate that contain keratin. It attacked the disulfide bond of substrate and involve in keratin degradation. Human hair, feathers, animal hard tissues, horns, claws, and hooves all contain keratin.. It exists in two form alpha keratin (found in soft tissues) and beta keratin (found in hard tissue). By taking part in the degradation of keratin, keratinases derived from microbial sources, often referred to as microbial keratinases, are important in the process of turning wastes containing keratin into products with added value. Chicken feathers contain high level of keratin protein content than other sources and became a suitable protein source. Keratinase production occurs at near alkaline pH and thermophilic temperatures. The bioprocessing of keratinous waste benefits greatly from the use of keratinases. Additionally, it lessens the issue caused by poultry excrement. The use of feather meal, along with keratinase, improves the digestion of proteins and amino acids.

Keywords: mili litre (ml), micro litre (Ul), TCA - trichloroacetic acid, OD - optical density

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454 Reliability-Based Ductility Seismic Spectra of Structures with Tilting

Authors: Federico Valenzuela-Beltran, Sonia E. Ruiz, Alfredo Reyes-Salazar, Juan Bojorquez

Abstract:

A reliability-based methodology which uses structural demand hazard curves to consider the increment of the ductility demands of structures with tilting is proposed. The approach considers the effect of two orthogonal components of the ground motions as well as the influence of soil-structure interaction. The approach involves the calculation of ductility demand hazard curves for symmetric systems and, alternatively, for systems with different degrees of asymmetry. To get this objective, demand hazard curves corresponding to different global ductility demands of the systems are calculated. Next, Uniform Exceedance Rate Spectra (UERS) are developed for a specific mean annual rate of exceedance value. Ratios between UERS corresponding to asymmetric and to symmetric systems located in soft soil of the valley of Mexico are obtained. Results indicate that the ductility demands corresponding to tilted structures may be several times higher than those corresponding to symmetric structures, depending on several factors such as tilting angle and vibration period of structure and soil.

Keywords: asymmetric yielding, seismic performance, structural reliability, tilted structures

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453 Bio-Mimetic Foot Design for Legged Locomotion over Unstructured Terrain

Authors: Hannah Kolano, Paul Nadan, Jeremy Ryan, Sophia Nielsen

Abstract:

The hooves of goats and other ruminants, or the family Ruminantia, are uniquely structured to adapt to rough terrain. Their hooves possess a hard outer shell and a soft interior that allow them to both conform to uneven surfaces and hook onto prominent features. In an effort to apply this unique mechanism to a robotics context, artificial feet for a hexapedal robot have been designed based on the hooves of ruminants to improve the robot’s ability to traverse unstructured environments such as those found on a rocky planet or asteroid, as well as in earth-based environments such as rubble, caves, and mountainous regions. The feet were manufactured using a combination of 3D printing and polyurethane casting techniques and attached to a commercially available hexapedal robot. The robot was programmed with a terrain-adaptive gait and proved capable of traversing a variety of uneven surfaces and inclines. This development of more adaptable robotic feet allows legged robots to operate in a wider range of environments and expands their possible applications.

Keywords: biomimicry, legged locomotion, robotic foot design, ruminant feet, unstructured terrain navigation

Procedia PDF Downloads 121