Search results for: retaining structure
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7923

Search results for: retaining structure

6393 A Modified Periodic 2D Cellular Re-Entrant Honeycomb Model to Enhance the Auxetic Elastic Properties

Authors: Sohaib Z. Khan, Farrukh Mustahsan, Essam R. I. Mahmoud, S. H. Masood

Abstract:

Materials or structures that contract laterally on the application of a compressive load and vice versa are said to be Auxetic materials which exhibit Negative Poisson’s Ratio (NPR). Numerous auxetic structures are proposed in the literature. One of the most studied periodic auxetic structure is the re-entrant honeycomb model. In this paper, a modified re-entrant model is proposed to enhance the auxetic behavior. The paper aimed to investigate the elastic behaviour of the proposed model to improve Young’s modulus and NPR by evaluating the analytical model. Finite Element Analysis (FEA) is also conducted to support the analytical results. A significant increment in Young’s modulus and NPR can be achieved in one of the two orthogonal directions of the loading at the cost of compromising these values in other direction. The proposed modification resulted in lower relative densities when compared to the existing re-entrant honeycomb structure. A trade-off in the elastic properties in one direction at low relative density makes the proposed model suitable for uni-direction applications where higher stiffness and NPR is required, and strength to weight ratio is important.

Keywords: 2D model, auxetic materials, re-entrant honeycomb, negative Poisson's ratio

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6392 Ageing, the Reality, and Its Gender Dimension

Authors: Forhana Rahman Noor, Shafia Jannat Khanam

Abstract:

The image of old age in Bangladesh is associated with graying of hair, wrinkling of skin, with poor physical health, and decreased ability to work. The common expression “bura hoechi”, to be aged, means to be limited in terms of performing economically productive activities, known as ‘work’. For ‘old-old’ age, there is a saying, “uthan akhon onek dure”, which literally means “even the courtyard is like a very distant place (for an old person).” Traditionally, Bengali society had a structure caring the life of older people. It was common in the joint families of Bangladeshi culture. The situation has been changing. Complexities of the societies with growing rapid urbanization are influencing the traditional respects and caring structure of the elderly persons and facing social challenges. Bangladesh is projected to have 10 percent of its population of age 60 years and above in the year 2025. The ageing process is expected to accelerate in the next century, mainly because the large cohorts born in 1950s and 1960s respectively will be joining the ranks of 60 years and over during this period. The decline in mortality, particularly at young ages, also means that a higher proportion of the large cohorts will survive to old age. The country does not have enough policy or strategy to face this upcoming challenge for the aged persons which needs immediate attention.

Keywords: ageing, gender, dimension, elderly population, Bangladesh

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6391 Thermal Ageing of a 316 Nb Stainless Steel: From Mechanical and Microstructural Analyses to Thermal Ageing Models for Long Time Prediction

Authors: Julien Monnier, Isabelle Mouton, Francois Buy, Adrien Michel, Sylvain Ringeval, Joel Malaplate, Caroline Toffolon, Bernard Marini, Audrey Lechartier

Abstract:

Chosen to design and assemble massive components for nuclear industry, the 316 Nb austenitic stainless steel (also called 316 Nb) suits well this function thanks to its mechanical, heat and corrosion handling properties. However, these properties might change during steel’s life due to thermal ageing causing changes within its microstructure. Our main purpose is to determine if the 316 Nb will keep its mechanical properties after an exposition to industrial temperatures (around 300 °C) during a long period of time (< 10 years). The 316 Nb is composed by different phases, which are austenite as main phase, niobium-carbides, and ferrite remaining from the ferrite to austenite transformation during the process. Our purpose is to understand thermal ageing effects on the material microstructure and properties and to submit a model predicting the evolution of 316 Nb properties as a function of temperature and time. To do so, based on Fe-Cr and 316 Nb phase diagrams, we studied the thermal ageing of 316 Nb steel alloys (1%v of ferrite) and welds (10%v of ferrite) for various temperatures (350, 400, and 450 °C) and ageing time (from 1 to 10.000 hours). Higher temperatures have been chosen to reduce thermal treatment time by exploiting a kinetic effect of temperature on 316 Nb ageing without modifying reaction mechanisms. Our results from early times of ageing show no effect on steel’s global properties linked to austenite stability, but an increase of ferrite hardness during thermal ageing has been observed. It has been shown that austenite’s crystalline structure (cfc) grants it a thermal stability, however, ferrite crystalline structure (bcc) favours iron-chromium demixion and formation of iron-rich and chromium-rich phases within ferrite. Observations of thermal ageing effects on ferrite’s microstructure were necessary to understand the changes caused by the thermal treatment. Analyses have been performed by using different techniques like Atomic Probe Tomography (APT) and Differential Scanning Calorimetry (DSC). A demixion of alloy’s elements leading to formation of iron-rich (α phase, bcc structure), chromium-rich (α’ phase, bcc structure), and nickel-rich (fcc structure) phases within the ferrite have been observed and associated to the increase of ferrite’s hardness. APT results grant information about phases’ volume fraction and composition, allowing to associate hardness measurements to the volume fractions of the different phases and to set up a way to calculate α’ and nickel-rich particles’ growth rate depending on temperature. The same methodology has been applied to DSC results, which allowed us to measure the enthalpy of α’ phase dissolution between 500 and 600_°C. To resume, we started from mechanical and macroscopic measurements and explained the results through microstructural study. The data obtained has been match to CALPHAD models’ prediction and used to improve these calculations and employ them to predict 316 Nb properties’ change during the industrial process.

Keywords: stainless steel characterization, atom probe tomography APT, vickers hardness, differential scanning calorimetry DSC, thermal ageing

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6390 Student Motivation as an Important Factor in Teaching and Learning English Language

Authors: Deborah Asibu Abu

Abstract:

Motivation is the process that initiates, guides, and maintains goal-oriented behaviors. It is one of the most important ingredients in teaching and learning yet it does not come by chance; it involves necessary strategies appropriate to achieve a common goal. In learning, the psychological attention of the student is very important. This helps them to imagine whatever is being taught for a simple understanding, nonetheless, many students will be able to imagine how the environment is in social studies or how the bones or plant is, in integrated Science but will find it difficult to imagine what subject-verb agreement or phrases and clauses actually looks like until they are motivated or with the use of TLM’s to stir their interest to learn and forever remember. For students to be able to receive the motivation they need, there must be an effective relationship between the teacher and the student as well as the use of strategies for effectual execution of achievable goals. Every teacher must understand the importance of motivation by applying various kinds of teaching methodology, especially in the English Language as a subject. Hence this paper suggests some important factors necessary for student’s motivation in teaching and learning English Language, it handles what teaching method is, types of motivation, educational curriculum structure of many, what suitable teaching methods can achieve, appropriate teachers’ disposition, learning environment as tool for motivation and some other domestic factors that can also influence student motivation.

Keywords: english language, teacher-student relationship, curriculum structure, learning environment

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6389 Advanced Seismic Retrofit of a School Building by a DFP Base Isolation Solution

Authors: Stefano Sorace, Gloria Terenzi

Abstract:

The study of a base isolation seismic retrofit solution for a reinforced concrete school building is presented in this paper. The building was assumed as a benchmark structure for a Research Project financed by the Italian Department of Civil Protection, and is representative of several similar public edifices designed with earlier Technical Standards editions, in Italy as well as in other earthquake-prone European countries. The structural characteristics of the building, and a synthesis of the investigation campaigns developed on it, are initially presented. The mechanical parameters, dimensions, locations and installation details of the base isolation system, incorporating double friction pendulum sliding bearings as protective devices, are then illustrated, along with the performance assessment analyses carried out in original and rehabilitated conditions according to a full non-linear dynamic approach. The results of the analyses show a remarkable enhancement of the seismic response capacities of the structure in base-isolated configuration. This allows reaching the high performance levels postulated in the rehabilitation design with notably lower costs and architectural intrusion as compared to traditional retrofit interventions designed for the same objectives.

Keywords: seismic retrofit, seismic assessment, r/c structures, school buildings, base isolation

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6388 Disperse Innovation in the Turning German Energy Market

Authors: J. Gochermann

Abstract:

German energy market is under historical change. Turning-off the nuclear power plants and intensive subsidization of the renewable energies causes a paradigm change from big central energy production and distribution to more local structures, bringing the energy production near to the consumption. The formerly big energy market with only a few big energy plants and grid operating companies is changing into a disperse market with growing numbers of small and medium size companies (SME) generating new value-added products and services. This change in then energy market, in Germany called the “Energiewende”, inverts also the previous innovation system. Big power plants and large grids required also big operating companies. Innovations in the energy market focused mainly on big projects and complex energy technologies. Innovation in the new energy market structure is much more dispersed. Increasing number of SME is now able to develop energy production and storage technologies, smart technologies to control the grids, and numerous new energy related services. Innovation is now regional distributed, which is a remarkable problem for the old big energy companies. The paper will explain the change in the German energy market and the paradigm change as well as the consequences for the innovation structure in the German energy market. It will show examples how SME participate from this change and how innovation systems, as well for the big companies and for SME, can be adapted.

Keywords: changing energy markets, disperse innovation, new value-added products and services, SME

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6387 Characteristics of Cumulative Distribution Function of Grown Crack Size at Specified Fatigue Crack Propagation Life under Different Maximum Fatigue Loads in AZ31

Authors: Seon Soon Choi

Abstract:

Magnesium alloy has been widely used in structure such as an automobile. It is necessary to consider probabilistic characteristics of a structural material because a fatigue behavior of a structure has a randomness and uncertainty. The purpose of this study is to find the characteristics of the cumulative distribution function (CDF) of the grown crack size at a specified fatigue crack propagation life and to investigate a statistical crack propagation in magnesium alloys. The statistical fatigue data of the grown crack size are obtained through the fatigue crack propagation (FCP) tests under different maximum fatigue load conditions conducted on the replicated specimens of magnesium alloys. The 3-parameter Weibull distribution is used to find the CDF of grown crack size. The CDF of grown crack size in case of larger maximum fatigue load has longer tail in below 10 percent and above 90 percent. The fatigue failure occurs easily as the tail of CDF of grown crack size becomes long. The fatigue behavior under the larger maximum fatigue load condition shows more rapid propagation and failure mode.

Keywords: cumulative distribution function, fatigue crack propagation, grown crack size, magnesium alloys, maximum fatigue load

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6386 Lock in, Lock Out: A Double Lens Analysis of Local Media Paywall Strategies and User Response

Authors: Mona Solvoll, Ragnhild Kr. Olsen

Abstract:

Background and significance of the study: Newspapers are going through radical changes with increased competition, eroding readerships and declining advertising resulting in plummeting overall revenues. This has lead to a quest for new business models, focusing on monetizing content. This research paper investigates both how local online newspapers have introduced user payment and how the audience has received these changes. Given the role of local media in keeping their communities informed and those in power accountable, their potential impact on civic engagement and cultural integration in local communities, the business model innovations of local media deserves far more research interest. Empirically, the findings are interesting for local journalists, local media managers as well as local advertisers. Basic methodologies: The study is based on interviews with commercial leaders in 20 Norwegian local newspapers in addition to a national survey data from 1600 respondents among local media users. The interviews were conducted in the second half of 2015, while the survey was conducted in September 2016. Theoretically, the study draws on the business model framework. Findings: The analysis indicates that paywalls aim more at reducing digital cannibalisation of print revenue than about creating new digital income. The newspapers are mostly concerned with retaining “old” print subscribers and transform them into digital subscribers. However, this strategy may come at a high price for newspapers if their defensive print strategy drives away younger digital readership and hamper their recruitment potential for new audiences as some previous studies have indicated. Analysis of young reader news habits indicates that attracting the younger audience to traditional local news providers is particularly challenging and that they are more prone to seek alternative news sources than the older audience is. Conclusion: The paywall strategy applied by the local newspapers may be well fitted to stabilise print subscription figures and facilitate more tailored and better services for already existing customers, but far less suited for attracting new ones. The paywall is a short-sighted strategy, which drives away younger readers and paves the road for substitute offerings, particularly Facebook.

Keywords: business model, newspapers, paywall, user payment

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6385 A Potential Spin-orbit Torque Device Using the Tri-layer Structure

Authors: Chih-Wei Cheng, Wei-Jen Chan, Yu-Han Huang, Yi-Tsung Lin, Yen-Wei Huang, Min-Cheng Chen, Shou-Zen Chang, G. Chern, Yuan-Chieh Tseng

Abstract:

How to develop spin-orbit-torque (SOT) devices with the virtues of field-free, perpendicular magnetic anisotropy (PMA), and low switching current is one of the many challenges in spintronics today. We propose a CoFeB/Ta/CoFeB tri-layer antiferromagnetic SOT device that could meet the above requirements. The device’s PMA was developed by adopting CoFeB–MgO interface. The key to the success of this structure is to ensure that (i)changes of the inter-layer coupling(IEC) and CoFeB anisotropy can occur simultaneously; (ii) one of the CoFeB needs to have a slightly tilted moment in the beginning. When sufficient current is given, the SHEreverses the already-tiltedCoFeB, and the other CoFeB can be reversed simultaneously by the IEC with the field-free nature. Adjusting the thickness of Ta can modify the coupling state to reduce the switching current while the field-free nature was preserved. Micromagnetic simulation suggests that the Néel orange peel effect (NOPE) is non-negligible due to interface roughness and coupling effect in the presence of perpendicular anisotropy. Fortunately, the Néel field induced by the NOPE appears to favor the field-free reversal.

Keywords: CoFeB, spin-orbit torque, antiferromagnetic, MRAM, trilayer

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6384 Performance of Buildings with Base-Isolation System under Geometric Irregularities

Authors: Firoz Alam Faroque, Ankur Neog

Abstract:

Earthquake causes significant loss of lives and severe damage to infrastructure. Base isolator is one of the most suitable solutions to make a building earthquake resistant. Base isolation consists of installing an isolator along with the steel plates covered with pads of strong material like steel, rubber, etc. In our study, we have used lead rubber bearing (LRB). The basic idea of seismic isolation is based on the reduction of the earthquake-induced inertia forces by shifting the fundamental period of the structure out of dangerous resonance range, and concentration of the deformation and energy dissipation demands at the isolation and energy dissipation systems, which are designed for this purpose. In this paper, RC frame buildings have been modeled and analyzed by response spectrum method using ETABS software. The LRB used in the model is designed as per uniform building code (UBC) 97. It is found that time period for the base isolated structures are higher than that of the fixed base structure and the value of base shear significantly reduces in the case of base-isolated buildings. It has also been found that buildings with vertical irregularities give better performance as compared to building with plan irregularities using base isolators.

Keywords: base isolation, base shear, irregularities in buildings, lead rubber bearing (LRB)

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6383 Moulding Photovoice to Community: Supporting Aboriginal People Experiencing Homelessness to Share Their Stories through Photography

Authors: Jocelyn Jones, Louise Southalan, Lindey Andrews, Mandy Wilson, Emma Vieira, Jackie Oakley, Dorothy Bagshaw, Alice V. Brown, Patrick Egan, Duc Dau, Lucy Spanswick

Abstract:

Working with people experiencing homelessness requires careful use of methods that support them to comfortably share their experiences. This is particularly important for Aboriginal and Torres Strait Islander peoples, the traditional owners of Australia, who have experienced intergenerational and compounding trauma since colonisation. Aboriginal cultures regularly experience research fatigue and distrust in research’s potential for impact. They often view research as an extraction -a process of taking the knowledge that empowers the research team and its institution, rather than benefiting those being researched. Through a partnership between an Aboriginal Community Controlled Organisation and a university research institute, we conducted a community-driven research project with 70-90 Aboriginal people experiencing homelessness in Perth, Western Australia. The project aimed to listen to and advocate for the voices of those who are experiencing homelessness, guided by the Aboriginal community. In consultation with Aboriginal Elders, we selected methods that are considered culturally safe, including those who would prefer to express their experiences creatively. This led us to run a series of Photovoice workshops -an established method that supports people to share their experiences through photography. This method treats participants as experts and is regularly used with marginalised groups across the world. We detail our experience and lessons in using Photovoice with Aboriginal community members experiencing homelessness. This includes the ways the method needed to be moulded to community needs and driven by their individual choices, such as being dynamic in the length of time participants would spend with us, how we would introduce the method to them, and providing support workers for participants when taking photos. We also discuss lessons in establishing and retaining engagement and how the method was successful in supporting participants to comfortably share their stories. Finally, we outline the insights into homelessness that the method offered, including highlighting the difficulty experienced by participants in transitioning from homelessness to accommodation and the diversity of hopes people who have experienced homelessness have for the future.

Keywords: Aboriginal and Torres Strait Islander peoples, photovoice, homelessness, community-led research

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6382 Application of Micro-Tunneling Technique to Rectify Tilted Structures Constructed on Cohesive Soil

Authors: Yasser R. Tawfic, Mohamed A. Eid

Abstract:

Foundation differential settlement and supported structure tilting is an occasionally occurred engineering problem. This may be caused by overloading, changes in ground soil properties or unsupported nearby excavations. Engineering thinking points directly toward the logic solution for such problem by uplifting the settled side. This can be achieved with deep foundation elements such as micro-piles and macro-piles™, jacked piers and helical piers, jet grouted soil-crete columns, compaction grout columns, cement grouting or with chemical grouting, or traditional pit underpinning with concrete and mortar. Although, some of these techniques offer economic, fast and low noise solutions, many of them are quite the contrary. For tilted structures, with limited inclination, it may be much easier to cause a balancing settlement on the less-settlement side which shall be done carefully in a proper rate. This principal has been applied in Leaning Tower of Pisa stabilization with soil extraction from the ground surface. In this research, the authors attempt to introduce a new solution with a different point of view. So, micro-tunneling technique is presented in here as an intended ground deformation cause. In general, micro-tunneling is expected to induce limited ground deformations. Thus, the researchers propose to apply the technique to form small size ground unsupported holes to produce the target deformations. This shall be done in four phases: •Application of one or more micro-tunnels, regarding the existing differential settlement value, under the raised side of the tilted structure. •For each individual tunnel, the lining shall be pulled out from both sides (from jacking and receiving shafts) in slow rate. •If required, according to calculations and site records, an additional surface load can be applied on the raised foundation side. •Finally, a strengthening soil grouting shall be applied for stabilization after adjustment. A finite element based numerical model is presented to simulate the proposed construction phases for different tunneling positions and tunnels group. For each case, the surface settlements are calculated and induced plasticity points are checked. These results show the impact of the suggested procedure on the tilted structure and its feasibility. Comparing results also show the importance of the position selection and tunnels group gradual effect. Thus, a new engineering solution is presented to one of the structural and geotechnical engineering challenges.

Keywords: differential settlement, micro-tunneling, soil-structure interaction, tilted structures

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6381 Construction of QSAR Models to Predict Potency on a Series of substituted Imidazole Derivatives as Anti-fungal Agents

Authors: Sara El Mansouria Beghdadi

Abstract:

Quantitative structure–activity relationship (QSAR) modelling is one of the main computer tools used in medicinal chemistry. Over the past two decades, the incidence of fungal infections has increased due to the development of resistance. In this study, the QSAR was performed on a series of esters of 2-carboxamido-3-(1H-imidazole-1-yl) propanoic acid derivatives. These compounds have showed moderate and very good antifungal activity. The multiple linear regression (MLR) was used to generate the linear 2d-QSAR models. The dataset consists of 115 compounds with their antifungal activity (log MIC) against «Candida albicans» (ATCC SC5314). Descriptors were calculated, and different models were generated using Chemoffice, Avogadro, GaussView software. The selected model was validated. The study suggests that the increase in lipophilicity and the reduction in the electronic character of the substituent in R1, as well as the reduction in the steric hindrance of the substituent in R2 and its aromatic character, supporting the potentiation of the antifungal effect. The results of QSAR could help scientists to propose new compounds with higher antifungal activities intended for immunocompromised patients susceptible to multi-resistant nosocomial infections.

Keywords: quantitative structure–activity relationship, imidazole, antifungal, candida albicans (ATCC SC5314)

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6380 Corporate Governance and Performance of Islamic Banks in GCC Countries

Authors: Samir Srairi

Abstract:

This paper investigates the impact of the internal corporate governance on bank performance by constructing a corporate governance index (CGI) for 27 Islamic banks operating in five Arab Gulf countries. Using content analysis on the banks’ annual reports for 3 years (2011-2013), the index construction uses information on six important corporate governance mechanisms, namely board structure, risk management, transparency and disclosure, audit committee, Sharia supervisory board and investment account holders. The results demonstrate that Islamic banks adhere to 54% of the attributes addressed in the CGI. The most frequently reported and disclosed elements are Sharia supervisory board followed by board structure and risk management. The findings related to countries revealed that only two countries, the United Arab Emirates and Bahrain, possess a higher level of CGI. Our regression results provide evidence that Islamic banks with higher levels of corporate governance report high operating performance measured by return on assets and net interest margin. Finally, as of the effect of internal and external factors, we identified four variables that were associated with bank performance, namely size, equity, risk and concentration.

Keywords: governance mechanisms, corporate governance index, bank performance, Islamic banks, GCC countries

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6379 Evaluation of Expected Annual Loss Probabilities of RC Moment Resisting Frames

Authors: Saemee Jun, Dong-Hyeon Shin, Tae-Sang Ahn, Hyung-Joon Kim

Abstract:

Building loss estimation methodologies which have been advanced considerably in recent decades are usually used to estimate socio and economic impacts resulting from seismic structural damage. In accordance with these methods, this paper presents the evaluation of an annual loss probability of a reinforced concrete moment resisting frame designed according to Korean Building Code. The annual loss probability is defined by (1) a fragility curve obtained from a capacity spectrum method which is similar to a method adopted from HAZUS, and (2) a seismic hazard curve derived from annual frequencies of exceedance per peak ground acceleration. Seismic fragilities are computed to calculate the annual loss probability of a certain structure using functions depending on structural capacity, seismic demand, structural response and the probability of exceeding damage state thresholds. This study carried out a nonlinear static analysis to obtain the capacity of a RC moment resisting frame selected as a prototype building. The analysis results show that the probability of being extensive structural damage in the prototype building is expected to 0.004% in a year.

Keywords: expected annual loss, loss estimation, RC structure, fragility analysis

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6378 A New Co(II) Metal Complex Template with 4-dimethylaminopyridine Organic Cation: Structural, Hirshfeld Surface, Phase Transition, Electrical Study and Dielectric Behavior

Authors: Mohamed dammak

Abstract:

Great attention has been paid to the design and synthesis of novel organic-inorganic compounds in recent decades because of their structural variety and the large diversity of atomic arrangements. In this work, the structure for the novel dimethyl aminopyridine tetrachlorocobaltate (C₇H₁₁N₂)₂CoCl₄ prepared by the slow evaporation method at room temperature has been successfully discussed. The X-ray diffraction results indicate that the hybrid material has a triclinic structure with a P space group and features a 0D structure containing isolated distorted [CoCl₄]2- tetrahedra interposed between [C7H11N²⁻]+ cations forming planes perpendicular to the c axis at z = 0 and z = ½. The effect of the synthesis conditions and the reactants used, the interactions between the cationic planes, and the isolated [CoCl4]2- tetrahedra are employing N-H...Cl and C-H…Cl hydrogen bonding contacts. The inspection of the Hirshfeld surface analysis helps to discuss the strength of hydrogen bonds and to quantify the inter-contacts. A phase transition was discovered by thermal analysis at 390 K, and comprehensive dielectric research was reported, showing a good agreement with thermal data. Impedance spectroscopy measurements were used to study the electrical and dielectric characteristics over a wide range of frequencies and temperatures, 40 Hz–10 MHz and 313–483 K, respectively. The Nyquist plot (Z" versus Z') from the complex impedance spectrum revealed semicircular arcs described by a Cole-Cole model. An electrical circuit consisting of a link of grain and grain boundary elements is employed. The real and imaginary parts of dielectric permittivity, as well as tg(δ) of (C₇H₁₁N₂)₂CoCl₄ at different frequencies, reveal a distribution of relaxation times. The presence of grain and grain boundaries is confirmed by the modulus investigations. Electric and dielectric analyses highlight the good protonic conduction of this material.

Keywords: organic-inorganic, phase transitions, complex impedance, protonic conduction, dielectric analysis

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6377 Optimum Dimensions of Hydraulic Structures Foundation and Protections Using Coupled Genetic Algorithm with Artificial Neural Network Model

Authors: Dheyaa W. Abbood, Rafa H. AL-Suhaili, May S. Saleh

Abstract:

A model using the artificial neural networks and genetic algorithm technique is developed for obtaining optimum dimensions of the foundation length and protections of small hydraulic structures. The procedure involves optimizing an objective function comprising a weighted summation of the state variables. The decision variables considered in the optimization are the upstream and downstream cutoffs length sand their angles of inclination, the foundation length, and the length of the downstream soil protection. These were obtained for a given maximum difference in head, depth of impervious layer and degree of anisotropy.The optimization carried out subjected to constraints that ensure a safe structure against the uplift pressure force and sufficient protection length at the downstream side of the structure to overcome an excessive exit gradient. The Geo-studios oft ware, was used to analyze 1200 different cases. For each case the length of protection and volume of structure required to satisfy the safety factors mentioned previously were estimated. An ANN model was developed and verified using these cases input-output sets as its data base. A MatLAB code was written to perform a genetic algorithm optimization modeling coupled with this ANN model using a formulated optimization model. A sensitivity analysis was done for selecting the cross-over probability, the mutation probability and level ,the number of population, the position of the crossover and the weights distribution for all the terms of the objective function. Results indicate that the most factor that affects the optimum solution is the number of population required. The minimum value that gives stable global optimum solution of this parameters is (30000) while other variables have little effect on the optimum solution.

Keywords: inclined cutoff, optimization, genetic algorithm, artificial neural networks, geo-studio, uplift pressure, exit gradient, factor of safety

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6376 Urban Spatial Metamorphoses: The Case of Kazan City With Using GIS-Technologies

Authors: Irna Malganova

Abstract:

The paper assessed the effectiveness of the use of urban functional zoning using the method of M.A. Kramer by the example of Kazan city (Republic of Tatarstan, Russian Federation) using geoinformation technologies. On the basis of the data obtained, the calculations were carried out to obtain data on population density, overcoming geographic determinism, as well as the effectiveness of the formation of urban frameworks. The authors proposed recommendations for the effectiveness of municipal frameworks in the period from 2018 to 2021: economic, social, environmental and social. The study of effective territorial planning in a given period allows to display of the dynamics of planning changes, as well as assessment of changes in the formation of urban frameworks. Based on the incoming data obtained from the master plan of the municipal formation of Kazan, in the period from 2018 to 2021, there was an increase in population by 13841 people or 1.1% of the values of 2018. In addition, the area of Kazan increased by 2419.6 hectares. In the structure of the distribution of areas of functional zones, there was an increase in such zones of the municipality as zones of residential and public purpose. Changes in functional zoning, as well as territories requiring reorganization, are presented using geoinformation technologies in open-source software Quantum Geographic Information System (QGIS 3.32). According to the calculations based on the method of functional zoning efficiency by M.A. Kreimer, the territorial-planning structure of Kazan City is quite effective. However, in the development of spatial planning concepts, it is possible to emphasize the weakened interest of the population in the development of territorial planning documents. Thus, the approach to spatial planning of Kazan differs from foreign methods and approaches based on the joint development of planning directions and development of territories of municipalities between the developers of the planning structure, business representatives and the population. The population plays the role of the target audience on which territorial planning is oriented. It follows that there is a need to satisfy the opinions and demands of the population.

Keywords: spatial development, metamorphosis, Kazan city, spatial planning, efficiency, geographic determinism., GIS, QGIS

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6375 Effect of Enzymatic Modification on the Crystallinity of Cellulose Pulps

Authors: J. Janicki, M. Rom, C. Slusarczyk, J. Fabia, M. Siika-aho, K. Marjamaa, K. Kruus, K. Langfelder, C. Steel, M. Paloheimo, T. Puranen, S. Mäkinen, D. Wawro

Abstract:

The cellulose is one of the most abundant polymers in the world, however, its application in the high-end value products such as films or fibres, it triggered by the cellulose properties. The noticeable presence of hydrogen bonding reflected with partially crystalline structure makes the cellulose insoluble in common solvents and not meltable. The existing technologies, such as viscose process, suffer from environmental and economical problems, because of the risk of harmful chemicals liberation during the spinning process. The enzymatic modification of cellulose with endoglucanase makes it directly alkali soluble in NaOH solution, giving the opportunities for film and fibers formation. As the effect of enzymatic treatment, there are observed changes in crystalline structure and accompanying changes of the affinity of cellulose to water, demonstrated by water retention value. The objective of the project ELMO - Novel carbohydrate modifying enzymes for fibre modification is is to develop new enzyme products for modification of dissolving grade pulps. The aim is to increase the reactivity of dissolving grade pulps and remove residual hemicellulose. The scientific aim of this paper is to present the effect of enzymatic treatment on the crystallinity and affinity to water of cellulose pulps modified with enzymes.

Keywords: cellulose, crystallinity, WAXS, enzyme

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6374 Influence of Cobalt Incorporation on the Structure and Properties of SOL-Gel Derived Mesoporous Bioglass Nanoparticles

Authors: Ahmed El-Fiqi, Hae-Won Kim

Abstract:

Incorporation of therapeutic elements such as Sr, Cu and Co into bioglass structure and their release as ions is considered as one of the promising approaches to enhance cellular responses, e.g., osteogenesis and angiogenesis. Here, cobalt as angiogenesis promoter has been incorporated (at 0, 1 and 4 mol%) into sol-gel derived calcium silicate mesoporous bioglass nanoparticles. The composition and structure of cobalt-free (CFN) and cobalt-doped (CDN) mesoporous bioglass nanoparticles have been analyzed by X-ray fluorescence (XRF), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Fourier-Transform Infra-red spectroscopy (FT-IR). The physicochemical properties of CFN and CDN have been investigated using high-resolution transmission electron microscopy (HR-TEM), Selected area electron diffraction (SAED), and Energy-dispersive X-ray (EDX). Furthermore, the textural properties, including specific surface area, pore-volume, and pore size, have been analyzed from N²⁻sorption analyses. Surface charges of CFN and CDN were also determined from surface zeta potential measurements. The release of ions, including Co²⁺, Ca²⁺, and SiO₄⁴⁻ has been analyzed using inductively coupled plasma atomic emission spectrometry (ICP-AES). Loading and release of diclofenac as an anti-inflammatory drug model were explored in vitro using Ultraviolet-visible spectroscopy (UV-Vis). XRD results ensured the amorphous state of CFN and CDN whereas, XRF further confirmed that their chemical compositions are very close to the designed compositions. HR-TEM analyses unveiled nanoparticles with spherical morphologies, highly mesoporous textures, and sizes in the range of 90 - 100 nm. Moreover, N²⁻ sorption analyses revealed that the nanoparticles have pores with sizes of 3.2 - 2.6 nm, pore volumes of 0.41 - 0.35 cc/g and highly surface areas in the range of 716 - 830 m²/g. High-resolution XPS analysis of Co 2p core level provided structural information about Co atomic environment and it confirmed the electronic state of Co in the glass matrix. ICP-AES analysis showed the release of therapeutic doses of Co²⁺ ions from 4% CDN up to 100 ppm within 14 days. Finally, diclofenac loading and release have ensured the drug/ion co-delivery capability of 4% CDN.

Keywords: mesoporous bioactive glass, nanoparticles, cobalt ions, release

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6373 Collapse Capacity Assessment of Inelastic Structures under Seismic Sequences

Authors: Shahrzad Mohammadi, Ghasem Boshrouei Sharq

Abstract:

All seismic design codes are based on the determination of the design earthquake without taking into account the effects of aftershocks in the design practice. In regions with a high level of seismicity, the occurrence of several aftershocks of various magnitudes and different time lags is very likely. This research aims to estimate the collapse capacity of a 10-story steel bundled tube moment frame subjected to as-recorded seismic sequences. The studied structure is designed according to the seismic regulations of the fourth revision of the Iranian code of practice for the seismic-resistant design of buildings (Code No.2800). A series of incremental dynamic analyses (IDA) is performed up to the collapse level of the intact structure. Then, in order to demonstrate the effects of aftershock events on the collapse vulnerability of the building, aftershock IDA analyzes are carried out. To gain deeper insight, collapse fragility curves are developed and compared for both series. Also, a study on the influence of various ground motion characteristics on collapse capacity is carried out. The results highlight the importance of considering the decisive effects of aftershocks in seismic codes due to their contribution to the occurrence of collapse.

Keywords: IDA, aftershock, bundled tube frame, fragility assessment, GM characteristics, as-recorded seismic sequences

Procedia PDF Downloads 142
6372 Building Safety Through Real-time Design Fire Protection Systems

Authors: Mohsin Ali Shaikh, Song Weiguo, Muhammad Kashan Surahio, Usman Shahid, Rehmat Karim

Abstract:

When the area of a structure that is threatened by a disaster affects personal safety, the effectiveness of disaster prevention, evacuation, and rescue operations can be summarized by three assessment indicators: personal safety, property preservation, and attribution of responsibility. These indicators are applicable regardless of the disaster that affects the building. People need to get out of the hazardous area and to a safe place as soon as possible because there's no other way to respond. The results of the tragedy are thus closely related to how quickly people are advised to evacuate and how quickly they are rescued. This study considers present fire prevention systems to address catastrophes and improve building safety. It proposes the methods of Prevention Level for Deployment in Advance and Spatial Transformation by Human-Machine Collaboration. We present and prototype a real-time fire protection system architecture for building disaster prevention, evacuation, and rescue operations. The design encourages the use of simulations to check the efficacy of evacuation, rescue, and disaster prevention procedures throughout the planning and design phase of the structure.

Keywords: prevention level, building information modeling, quality management system, simulated reality

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6371 The Revival of Asakusa Entertainment Streets and Social Conflicts Since Its Inceptive Point, the Post-war Time

Authors: Seung Oh, Satoshi Okada

Abstract:

Today, religious organizations that have long existed alongside local people are being challenged by social changes in the districts they control. The influence of religious organizations is declining everywhere as locals seeking diversity and economic benefits become more interested in developing projects that attract investors and increase market value instead of opting for conservation. Religions whose moral and philosophical stance rejects materialism have a limited capacity to act as agents of local development in modern society. However, in Tokyo, the city’s oldest temple, Senso-Ji played a vital role in the local development of Asakusa, as an entertainment district while nevertheless retaining the area’s traditional character, despite almost complete destruction caused by the Tokyo air raids. The temple played a vigorous role as a mediator between the community and the Tokyo Metropolitan Government as a spokesman for common interests. This research, therefore, examines the social conflicts that Senso-Ji has confronted with regard to the pressures of development of Asakusa on the one hand, and the legitimacy of perpetuating its traditional religious and cultural role in local society on the other. First, this article examines Senso-Ji’s place in society based on its location in the history of Japanese Buddhism, which existed to offer spiritual and practical help to the ordinary people, and to investigate its social legitimacy as a local stakeholder and historical institution. Second, this paper considers the impact of the social changes that Asakusa had undergone during the Meiji and Taisho eras, by examining the social conflicts and changes in the Asakusa entertainment district, taking the Tokyo Air Raids as the Inceptive Point (IP). Third, it reconsiders how Senso-Ji responded to today’s growth-oriented local developments, as proposed by Tokyo’s Metropolitan planning authorities along lines commonly seen in all cities. Studying the role of Senso-Ji in the development of Asakusa can serve as a case study to justify the involvement of religious institutions in local issues and as a useful and practical example of progressive development which nevertheless permitted conservation of traditional features, as a result of pressure from social groups in a way that may be useful for other places facing similar problems.

Keywords: Architecture, Urban Design, Urban Planning, Preservation, Conservation, Social Science

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6370 Resilient Modulus and Deformation Responses of Waste Glass in Flexible Pavement System

Authors: M. Al-Saedi, A. Chegenizadeh, H. Nikraz

Abstract:

Experimental investigations are conducted to assess a layered structure of glass (G) - rock (R) blends under the impact of repeated loading. Laboratory tests included sieve analyses, modified compaction test and repeated load triaxial test (RLTT) is conducted on different structures of stratified GR samples to reach the objectives of this study. Waste materials are such essential components in the climate system, and also commonly used in minimising the need for natural materials in many countries. Glass is one of the most widely used groups of waste materials which have been extensively using in road applications. Full range particle size and colours of glass are collected and mixed at different ratios with natural rock material trying to use the blends in pavement layers. Whole subsurface specimen sequentially consists of a single layer of R and a layer of G-R blend. 12G/88R and 45G/55R mix ratios are employed in this research, the thickness of G-R layer was changed, and the results were compared between the pure rock and the layered specimens. The relations between resilient module (Mr) and permanent deformation with sequence number are presented. During the earlier stages of RLTT, the results indicated that the 45G/55R specimen shows higher moduli than R specimen.

Keywords: Rock base course, Layered Structure, Glass, Resilient Modulus

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6369 Development of Mesoporous Gel Based Nonwoven Structure for Thermal Barrier Application

Authors: R. P. Naik, A. K. Rakshit

Abstract:

In recent years, with the rapid development in science and technology, people have increasing requirements on uses of clothing for new functions, which contributes to opportunities for further development and incorporation of new technologies along with novel materials. In this context, textiles are of fast decalescence or fast heat radiation media as per as comfort accountability of textile articles are concern. The microstructure and texture of textiles play a vital role in determining the heat-moisture comfort level of the human body because clothing serves as a barrier to the outside environment and a transporter of heat and moisture from the body to the surrounding environment to keep thermal balance between body heat produced and body heat loss. The main bottleneck which is associated with textile materials to be successful as thermal insulation materials can be enumerated as; firstly, high loft or bulkiness of material so as to provide predetermined amount of insulation by ensuring sufficient trapping of air. Secondly, the insulation depends on forced convection; such convective heat loss cannot be prevented by textile material. Third is that the textile alone cannot reach the level of thermal conductivity lower than 0.025 W/ m.k of air. Perhaps, nano-fibers can do so, but still, mass production and cost-effectiveness is a problem. Finally, such high loft materials for thermal insulation becomes heavier and uneasy to manage especially when required to carry over a body. The proposed works aim at developing lightweight effective thermal insulation textiles in combination with nanoporous silica-gel which provides the fundamental basis for the optimization of material properties to achieve good performance of the clothing system. This flexible nonwoven silica-gel composites fabric in intact monolith was successfully developed by reinforcing SiO2-gel in thermal bonded nonwoven fabric via sol-gel processing. Ambient Pressure Drying method is opted for silica gel preparation for cost-effective manufacturing. The formed structure of the nonwoven / SiO₂ -gel composites were analyzed, and the transfer properties were measured. The effects of structure and fibre on the thermal properties of the SiO₂-gel composites were evaluated. Samples are then tested against untreated samples of same GSM in order to study the effect of SiO₂-gel application on various properties of nonwoven fabric. The nonwoven fabric composites reinforced with aerogel showed intact monolith structure were also analyzed for their surface structure, functional group present, microscopic images. Developed product reveals a significant reduction in pores' size and air permeability than the conventional nonwoven fabric. Composite made from polyester fibre with lower GSM shows lowest thermal conductivity. Results obtained were statistically analyzed by using STATISTICA-6 software for their level of significance. Univariate tests of significance for various parameters are practiced which gives the P value for analyzing significance level along with that regression summary for dependent variable are also studied to obtain correlation coefficient.

Keywords: silica-gel, heat insulation, nonwoven fabric, thermal barrier clothing

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6368 Revealing the Structural and Dynamic Properties of Betaine Aldehyde Dehydrogenase 2 from Rice (Oryza sativa): Simulation Studies

Authors: Apisaraporn Baicharoen, Prapasiri Pongprayoon

Abstract:

Betaine aldehyde dehydrogenase 2 (BADH2) is an enzyme that inhibits the accumulation of 2-acetyl-1-pyrroline (2AP), a potent flavor compound in rice fragrance. BADH2 contains three domains (NAD-binding, substrate-binding, and oligomerization domains). It catalyzes the oxidation of amino aldehydes. The lack of BADH2 results in the formation of 2AP and consequently an increase in rice fragrance. To date, inadequate data on BADH2 structure and function are available. An insight into the nature of BADH2 can serve as one of key starting points for the production of high quality fragrant rice. In this study, we therefore constructed the homology model of BADH2 and employed 500-ns Molecular Dynamics simulations (MD) to primarily understand the structural and dynamic properties of BADH2. Initially, Ramachandran plot confirms the good quality of modeled protein structure. Principle Component Analysis (PCA) was also calculated to capture the protein dynamics. Among 3 domains, the results show that NAD binding site is found to be more flexible. Moreover, interactions from key amino acids (N162, E260, C294, and Y419) that are crucial for function are investigated.

Keywords: betaine aldehyde dehydrogenase 2, fragrant rice, homology modeling, molecular dynamics simulations

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6367 Developing a Mathematical Model for Trade-Off Analysis of New Green Products

Authors: M. R. Gholizadeh, N. Bhuiyan, M. Salari

Abstract:

In the near future, companies will be increasingly forced to shift their activities along a new road in order to decrease the harmful effects of their design, production and after-life on our environment. Products must meet environmental standards to not only prevent penalties but to consider the sustainability for future generations. However, the most important factor that companies will face is selecting a reasonable strategy to maximize their profit. Thus, companies need to have precise forecast from their profit after design stage through Trade-off analysis. This paper is an attempt to introduce a mathematical model that considers effective factors that impact the total profit when products are designed for resource and energy efficiency or recyclability. The modification is according to different strategies based on a Cost-Volume-Profit model. Here, the cost structure consists of Recycling cost, Development cost, Ramp-up cost, Production cost, and Pollution cost. Also, the model shows the effect of implementation of design for recyclable on revenue structure through revenue of used parts and revenue of recycled materials. A numerical example is used to evaluate the proposed model. Results show that fulfillment of Green Product Development not only can reduce the environmental impact of products but also it will increase profit of company in long term.

Keywords: green product, design for environment, C-V-P model, trade-off analysis

Procedia PDF Downloads 316
6366 Decision-Making using Fuzzy Linguistic Hypersoft Set Topology

Authors: Muhammad Saqlain, Poom Kumam

Abstract:

Language being an abstract system and creative act, is quite complicated as its meaning varies depending on the context. The context is determined by the empirical knowledge of a person, which is derived from observation and experience. About further subdivided attributes, the decision-making challenges may entail quantitative and qualitative factors. However, because there is no norm for putting a numerical value on language, existing approaches cannot carry out the operations of linguistic knowledge. The assigning of mathematical values (fuzzy, intuitionistic, and neutrosophic) to any decision-making problem; without considering any rule of linguistic knowledge is ambiguous and inaccurate. Thus, this paper aims to provide a generic model for these issues. This paper provides the linguistic set structure of the fuzzy hypersoft set (FLHSS) to solve decision-making issues. We have proposed the definition some basic operations like AND, NOT, OR, AND, compliment, negation, etc., along with Topology and examples, and properties. Secondly, the operational laws for the fuzzy linguistic hypersoft set have been proposed to deal with the decision-making issues. Implementing proposed aggregate operators and operational laws can be used to convert linguistic quantifiers into numerical values. This will increase the accuracy and precision of the fuzzy hypersoft set structure to deal with decision-making issues.

Keywords: linguistic quantifiers, aggregate operators, multi-criteria decision making (mcdm)., fuzzy topology

Procedia PDF Downloads 97
6365 Data Structure Learning Platform to Aid in Higher Education IT Courses (DSLEP)

Authors: Estevan B. Costa, Armando M. Toda, Marcell A. A. Mesquita, Jacques D. Brancher

Abstract:

The advances in technology in the last five years allowed an improvement in the educational area, as the increasing in the development of educational software. One of the techniques that emerged in this lapse is called Gamification, which is the utilization of video game mechanics outside its bounds. Recent studies involving this technique provided positive results in the application of these concepts in many areas as marketing, health and education. In the last area there are studies that cover from elementary to higher education, with many variations to adequate to the educators methodologies. Among higher education, focusing on IT courses, data structures are an important subject taught in many of these courses, as they are base for many systems. Based on the exposed this paper exposes the development of an interactive web learning environment, called DSLEP (Data Structure Learning Platform), to aid students in higher education IT courses. The system includes basic concepts seen on this subject such as stacks, queues, lists, arrays, trees and was implemented to ease the insertion of new structures. It was also implemented with gamification concepts, such as points, levels, and leader boards, to engage students in the search for knowledge and stimulate self-learning.

Keywords: gamification, Interactive learning environment, data structures, e-learning

Procedia PDF Downloads 495
6364 Comparative Study in Evaluating the Antioxidation Efficiency for Native Types Antioxidants Extracted from Crude Oil with the Synthesized Class

Authors: Mohammad Jamil Abd AlGhani

Abstract:

The natural native antioxidants N,N-P-methyl phenyl acetone and N,N-phenyl acetone were isolated from the Iraqi crude oil region of Kirkuk by ion exchange and their structure was characterized by spectral and chemical analysis methods. Tetraline was used as a liquid hydrocarbon to detect the efficiency of isolated molecules at elevated temperature (393 K) that it has physicochemical specifications and structure closed to hydrocarbons fractionated from crude oil. The synthesized universal antioxidant 2,6-ditertiaryisobutyl-p-methyl phenol (Unol) with known stochiometric coefficient of inhibition equal to (2) was used as a model for comparative evaluation at the same conditions. Modified chemiluminescence method was used to find the amount of absorbed oxygen and the induction periods in and without the existence of isolated antioxidants molecules. The results of induction periods and quantity of absorbed oxygen during the oxidation process were measured by manometric installation. It was seen that at specific equal concentrations of N,N-phenyl acetone and N, N-P-methyl phenyl acetone in comparison with Unol at 393 K were with (2) and (2.5) times efficient than do Unol. It means that they had the ability to inhibit the formation of new free radicals and prevent the chain reaction to pass from the propagation to the termination step rather than decomposition of formed hydroperoxides.

Keywords: antioxidants, chemiluminescence, inhibition, Unol

Procedia PDF Downloads 200