Search results for: independent sets
2153 Keying Effect During Fracture of Stainless Steel
Authors: Farej Ahmed Emhmmed
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Fracture of duplex stainless steels (DSS) was investigated in air and in 3.5 wt % NaCl solution. Tow sets of fatigued specimens were heat treated at 475ºC for different times and pulled to failure either in air or after kept in 3.5% NaCl with polarization of -900 mV/ SCE. Fracture took place in general by ferrite cleavage and austenite ductile fracture in transgranular mode. Specimens measured stiffness (Ms) was affected by the aging time, with higher values measured for specimens aged for longer times. Microstructural features played a role in "blocking" the crack propagation process leading to lower the CTOD values specially for specimens aged for short times. Unbroken ligaments/ austenite were observed at the crack wake. These features may exerted a bridging stress, blocking effect, at the crack tip giving resistance to the crack propagation process i.e the crack mouth opening was reduced. Higher stress intensity factor Kıc values were observed with increased amounts of crack growth suggesting longer zone of unbroken ligaments in the crack wake. The bridging zone was typically several mm in length. Attempt to model the bridge stress was suggested to understand the role of ligaments/unbroken austenite in increasing the fracture toughness factor.Keywords: stainless steels, fracture toughness, crack keying effect, ligaments
Procedia PDF Downloads 3632152 Implementation of a Multimodal Biometrics Recognition System with Combined Palm Print and Iris Features
Authors: Rabab M. Ramadan, Elaraby A. Elgallad
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With extensive application, the performance of unimodal biometrics systems has to face a diversity of problems such as signal and background noise, distortion, and environment differences. Therefore, multimodal biometric systems are proposed to solve the above stated problems. This paper introduces a bimodal biometric recognition system based on the extracted features of the human palm print and iris. Palm print biometric is fairly a new evolving technology that is used to identify people by their palm features. The iris is a strong competitor together with face and fingerprints for presence in multimodal recognition systems. In this research, we introduced an algorithm to the combination of the palm and iris-extracted features using a texture-based descriptor, the Scale Invariant Feature Transform (SIFT). Since the feature sets are non-homogeneous as features of different biometric modalities are used, these features will be concatenated to form a single feature vector. Particle swarm optimization (PSO) is used as a feature selection technique to reduce the dimensionality of the feature. The proposed algorithm will be applied to the Institute of Technology of Delhi (IITD) database and its performance will be compared with various iris recognition algorithms found in the literature.Keywords: iris recognition, particle swarm optimization, feature extraction, feature selection, palm print, the Scale Invariant Feature Transform (SIFT)
Procedia PDF Downloads 2402151 Vertical Electrical Sounding and Seismic Refraction Techniques in Resolving Groundwater Problems at Kujama Prison Farm, Kaduna, Nigeria
Authors: M. D. Dogara, C. G, Afuwai, O. O. Esther, A. M. Dawai
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For two decades, the inhabitants of Kujama Prison Farm faced problems of water for domestic and agricultural purposes, even after the drilling of three deep boreholes. The scarcity of this groundwater resource led to the geophysical investigation of the basement complex of the prison farm. Two geophysical techniques, vertical electrical sounding and seismic refraction methods were deployed to unravel the cause(s) of the non-productivity of the three boreholes. The area of investigation covered was 400,000 m2 of ten profiles with six investigative points. In all, 60 vertical electrical points were sounded, and sixty sets of seismic refraction data were collected using the forward and reverse approach. From the geoelectric sections, it is suggestive that the area is underlain by three to five geoelectric layers of varying thicknesses and resistivities. The result of the interpreted seismic data revealed two geovelocity layers, with velocities ranging between 478m/s to 1666m/s for the first layer and 1166m/s to 7141m/s for the second layer. From the combined results of the two techniques, it was suggestive that all the three unproductive boreholes were drilled at points that were neither weathered nor fractured. It was, therefore, suggested that new boreholes should be drilled at areas identified with depressed bedrock topography having geophysical evidence of intense weathering and fracturing within the fresh basement.Keywords: groundwater, Kujama prison farm, kaduna, nigeria, seismic refraction, vertical electrical sounding
Procedia PDF Downloads 1622150 Comparison Learning Vocabulary Implicitly and Explicitly
Authors: Akram Hashemi
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This study provided an empirical evidence for learners of elementary level of language proficiency to investigate the potential role of contextualization in vocabulary learning. Prior to the main study, pilot study was performed to determine the reliability and validity of the researcher-made pretest and posttest. After manifesting the homogeneity of the participants, the participants (n = 90) were randomly assigned into three equal groups, i.e., two experimental groups and a control group. They were pretested by a vocabulary test, in order to test participants' pre-knowledge of vocabulary. Then, vocabulary instruction was provided through three methods of visual instruction, the use of context and the use of conventional techniques. At the end of the study, all participants took the same posttest in order to assess their vocabulary gain. The results of independent sample t-test indicated that there is a significant difference between learning vocabulary visually and learning vocabulary contextually. The results of paired sample t-test showed that different teaching strategies have significantly different impacts on learners’ vocabulary gains. Also, the contextual strategy was significantly more effective than visual strategy in improving students’ performance in vocabulary test.Keywords: vocabulary instruction, explicit instruction, implicit instruction, strategy
Procedia PDF Downloads 3382149 Factors Determining the Women Empowerment through Microfinance: An Empirical Study in Sri Lanka
Authors: Y. Rathiranee, D. M. Semasinghe
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This study attempts to identify the factors influencing on women empowerment of rural area in Sri Lanka through micro finance services. Data were collected from one hundred (100) rural women involving self employment activities through a questionnaire using direct personal interviews. Judgment and Convenience Random sampling technique was used to select the sample size from three Divisional Secretariat divisions of Kandawalai, Poonakari and Karachchi in Kilinochchi District. The factor analysis was performed on fourteen (14) variables for screening and reducing the variables to identify the influencing factors on empowerment. Multiple regression analysis was used to identify the relationship between the three empowerment factors and the impact of micro-finance on overall empowerment of rural women. The result of this study summarized the variables into three factors namely decision making, freedom to mobility and family support and which are positively associated with empowerment. In addition to this the value of adjusted R2 is 0.248 indicates that all the variables extracted can be explained 24.8% of the variation in the women empowerment through microfinance. Independent variables of these three factors have a positive correlation with women empowerment as well as significant values at 5 percent level.Keywords: influencing factors, micro finance, rural women, women empowerment
Procedia PDF Downloads 4772148 Loneliness and Depression in Relation to Latchkey Situation
Authors: Samaneh Sadat Fattahi Massoom, Hossein Salimi Bajestani
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The study examines loneliness and depression in students who regularly care for themselves after school (latchkey students) in Mashhad and compares them with parent supervised students using a causal-comparative research method. The 270 participants, aged 7 -13, were selected using convenience and cluster random-assignment sampling. Independent t-test results showed significant differences between loneliness (-4.32, p ≤ 0.05) and depression (-3.02, p ≤0.05) among latchkey and non-latchkey students. Using the Pearson correlation test, significant correlation between depression and loneliness among latchkey students was also discovered (r=0.59, p ≤ 0.05). However, regarding non latchkey students, no significant difference between loneliness and depression was observed (r= 0.02. p ≥ 0.05). Multiple regression results also showed that depression variance can be determined by gender (22%) and loneliness (34%). The findings of this study, specifically the significant difference between latchkey and non-latchkey children regarding feelings of loneliness and depression, carries clear implications for parents. It can be concluded that mothers who spend most of their time working out of the house and devoid their children of their presence in the home may cause some form of mental distress like loneliness and depression. Moreover, gender differences affect the degree of these psychological disorders.Keywords: loneliness, depression, self-care students, latchkey and non-latchkey students, gender
Procedia PDF Downloads 4192147 Optimal Hybrid Linear and Nonlinear Control for a Quadcopter Drone
Authors: Xinhuang Wu, Yousef Sardahi
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A hybrid and optimal multi-loop control structure combining linear and nonlinear control algorithms are introduced in this paper to regulate the position of a quadcopter unmanned aerial vehicle (UAV) driven by four brushless DC motors. To this end, a nonlinear mathematical model of the UAV is derived and then linearized around one of its operating points. Using the nonlinear version of the model, a sliding mode control is used to derive the control laws of the motor thrust forces required to drive the UAV to a certain position. The linear model is used to design two controllers, XG-controller and YG-controller, responsible for calculating the required roll and pitch to maneuver the vehicle to the desired X and Y position. Three attitude controllers are designed to calculate the desired angular rates of rotors, assuming that the Euler angles are minimal. After that, a many-objective optimization problem involving 20 design parameters and ten objective functions is formulated and solved by HypE (Hypervolume estimation algorithm), one of the widely used many-objective optimization algorithms approaches. Both stability and performance constraints are imposed on the optimization problem. The optimization results in terms of Pareto sets and fronts are obtained and show that some of the design objectives are competing. That is, when one objective goes down, the other goes up. Also, Numerical simulations conducted on the nonlinear UAV model show that the proposed optimization method is quite effective.Keywords: optimal control, many-objective optimization, sliding mode control, linear control, cascade controllers, UAV, drones
Procedia PDF Downloads 742146 Nongovernmental Organisations’ Sustainable Strategic Planning and Its Impact on Donors’ Loyalty
Authors: Farah Mahmoud Attallah
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The nonprofit sector has been heavily rising with the rise of sustainable development in developed and developing countries. Most economies are putting high pressure on this sector, believing that nongovernmental organizations (NGOs) are one of the main rescues during crises worldwide. Talking about the Egyptian NGOs, the number of those organizations has reached an average of 50,278 organizations which is the highest number Egypt has faced through the past decade. However, with the rising number of those NGOs comes their incapability of sustaining their performance and fundraising. Additionally, donors who are considered the key partners for those organizations have become knowledgeable about this sector which made them more demanding, putting high pressure on those organizations to believe that there must be a valuable return for the economy in order to donate. This research study aims to study the impact of a sustainable strategic planning model on raising loyal donors; the proposed model of this research presents several independent variables determining their impact on donors' intention to become loyal.Keywords: nonprofit sector, non-governmental organizations, strategic planning, sustainable business model, CRM, RM
Procedia PDF Downloads 782145 High Harmonics Generation in Hexagonal Graphene Quantum Dots
Authors: Armenuhi Ghazaryan, Qnarik Poghosyan, Tadevos Markosyan
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We have considered the high-order harmonic generation in-plane graphene quantum dots of hexagonal shape by the independent quasiparticle approximation-tight binding model. We have investigated how such a nonlinear effect is affected by a strong optical wave field, quantum dot typical band gap and lateral size, and dephasing processes. The equation of motion for the density matrix is solved by performing the time integration with the eight-order Runge-Kutta algorithm. If the optical wave frequency is much less than the quantum dot intrinsic band gap, the main aspects of multiphoton high harmonic emission in quantum dots are revealed. In such a case, the dependence of the cutoff photon energy on the strength of the optical pump wave is almost linear. But when the wave frequency is comparable to the bandgap of the quantum dot, the cutoff photon energy shows saturation behavior with an increase in the wave field strength.Keywords: strong wave field, multiphoton, bandgap, wave field strength, nanostructure
Procedia PDF Downloads 1622144 The Statistical Significant of Adsorbents for Effective Zn(II) Ions Removal
Authors: Kiurski S. Jelena, Oros B. Ivana, Kecić S. Vesna, Kovačević M. Ilija, Aksentijević M. Snežana
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The adsorption efficiency of various adsorbents for the removal of Zn(II) ions from the waste printing developer was studied in laboratory batch mode. The maximum adsorption efficiency of 94.1% was achieved with unfired clay pellets size (d≈15 mm). The obtained values of adsorption efficiency was subjected to the independent samples t-test in order to investigate the statistically significant differences of the investigated adsorbents for the effective removal of Zn(II) ions from the waste printing developer. The most statistically significant differences of adsorption efficiencies for Zn(II) ions removal were obtained between unfired clay pellets size (d≈15 mm) and activated carbon (|t|= 6.909), natural zeolite (|t|= 10.380), mixture of activated carbon and natural zeolite (|t|= 9.865), bentonite (|t|= 6.159), fired clay (|t|= 6.641), fired clay pellets size (d≈5 mm) (|t|= 6.678), fired clay pellets size (d≈8 mm) (|t|= 3.422), respectively.Keywords: Adsorption efficiency, adsorbent, statistical analysis, zinc ion.
Procedia PDF Downloads 3922143 A Novel Approach to Design and Implement Context Aware Mobile Phone
Authors: G. S. Thyagaraju, U. P. Kulkarni
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Context-aware computing refers to a general class of computing systems that can sense their physical environment, and adapt their behaviour accordingly. Context aware computing makes systems aware of situations of interest, enhances services to users, automates systems and personalizes applications. Context-aware services have been introduced into mobile devices, such as PDA and mobile phones. In this paper we are presenting a novel approaches used to realize the context aware mobile. The context aware mobile phone (CAMP) proposed in this paper senses the users situation automatically and provides user context required services. The proposed system is developed by using artificial intelligence techniques like Bayesian Network, fuzzy logic and rough sets theory based decision table. Bayesian Network to classify the incoming call (high priority call, low priority call and unknown calls), fuzzy linguistic variables and membership degrees to define the context situations, the decision table based rules for service recommendation. To exemplify and demonstrate the effectiveness of the proposed methods, the context aware mobile phone is tested for college campus scenario including different locations like library, class room, meeting room, administrative building and college canteen.Keywords: context aware mobile, fuzzy logic, decision table, Bayesian probability
Procedia PDF Downloads 3712142 Board of Directors of Small and Medium-Sized Enterprises to Go Public: Characteristics and Moderating Factors
Authors: María-José Palacin-Sanchez, Filippo Di Pietro, Reyes Samaniego-Medina
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This article examines, in an institutional context such as Spanish one, the corporate board structure characteristics and determinants in entrepreneurial firms to go public. Specifically, it explores these issues through all the initial public offerings in the Spanish Alternative Equity Market (MAB), which is a market segment for smaller growing companies. The results show that: a) firm size, age of the company, and the reputation of the auditor and the nominated advisor and Corporate Governance Code favour a larger and more independent board structure that enhances its monitoring functions; and b) leverage, opportunities of growth, sector risk and ownership by executive directors all lead towards a smaller broad of directors where the role of entrepreneurship provided by executive directors remains crucial. This reflects the delicate balance of power between small-business entrepreneurs and financial equity market forces, which demand more transparency and monitoring in the companies.Keywords: board composition, board size, corporate governance, IPO, SMEs
Procedia PDF Downloads 4072141 Open Educational Resource in Online Mathematics Learning
Authors: Haohao Wang
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Technology, multimedia in Open Educational Resources, can contribute positively to student performance in an online instructional environment. Student performance data of past four years were obtained from an online course entitled Applied Calculus (MA139). This paper examined the data to determine whether multimedia (independent variable) had any impact on student performance (dependent variable) in online math learning, and how students felt about the value of the technology. Two groups of student data were analyzed, group 1 (control) from the online applied calculus course that did not use multimedia instructional materials, and group 2 (treatment) of the same online applied calculus course that used multimedia instructional materials. For the MA139 class, results indicate a statistically significant difference (p = .001) between the two groups, where group 1 had a final score mean of 56.36 (out of 100), group 2 of 70.68. Additionally, student testimonials were discussed in which students shared their experience in learning applied calculus online with multimedia instructional materials.Keywords: online learning, open educational resources, multimedia, technology
Procedia PDF Downloads 3792140 Estimation of Carbon Sequestration and Air Quality of Terrestrial Ecosystems Using Remote Sensing Techniques
Authors: Kanwal Javid, Shazia Pervaiz, Maria Mumtaz, Muhammad Ameer Nawaz Akram
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Forests and grasslands ecosystems play an important role in the global carbon cycle. Land management activities influence both ecosystems and enable them to absorb and sequester carbon dioxide (CO2). Similarly, in Pakistan, these terrestrial ecosystems are well known to mitigate carbon emissions and have a great source to supply a variety of services such as clean air and water, biodiversity, wood products, wildlife habitat, food, recreation and carbon sequestration. Carbon sequestration is the main agenda of developed and developing nations to reduce the impacts of global warming. But the amount of carbon storage within these ecosystems can be affected by many factors related to air quality such as land management, land-use change, deforestation, over grazing and natural calamities. Moreover, the long-term capacity of forests and grasslands to absorb and sequester CO2 depends on their health, productivity, resilience and ability to adapt to changing conditions. Thus, the main rationale of this study is to monitor the difference in carbon amount of forests and grasslands of Northern Pakistan using MODIS data sets and map results using Geographic Information System. Results of the study conclude that forests ecosystems are more effective in reducing the CO2 level and play a key role in improving the quality of air.Keywords: carbon sequestration, grasslands, global warming, climate change.
Procedia PDF Downloads 1912139 Wireless Sensor Networks Optimization by Using 2-Stage Algorithm Based on Imperialist Competitive Algorithm
Authors: Hamid R. Lashgarian Azad, Seyed N. Shetab Boushehri
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Wireless sensor networks (WSN) have become progressively popular due to their wide range of applications. Wireless Sensor Network is made of numerous tiny sensor nodes that are battery-powered. It is a very significant problem to maximize the lifetime of wireless sensor networks. In this paper, we propose a two-stage protocol based on an imperialist competitive algorithm (2S-ICA) to solve a sensor network optimization problem. The energy of the sensors can be greatly reduced and the lifetime of the network reduced by long communication distances between the sensors and the sink. We can minimize the overall communication distance considerably, thereby extending the lifetime of the network lifetime through connecting sensors into a series of independent clusters using 2SICA. Comparison results of the proposed protocol and LEACH protocol, which is common to solving WSN problems, show that our protocol has a better performance in terms of improving network life and increasing the number of transmitted data.Keywords: wireless sensor network, imperialist competitive algorithm, LEACH protocol, k-means clustering
Procedia PDF Downloads 1122138 A Two Tailed Secretary Problem with Multiple Criteria
Authors: Alaka Padhye, S. P. Kane
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The following study considers some variations made to the secretary problem (SP). In a multiple criteria secretary problem (MCSP), the selection of a unit is based on two independent characteristics. The units that appear before an observer are known say N, the best rank of a unit being N. A unit is selected, if it is better with respect to either first or second or both the characteristics. When the number of units is large and due to constraints like time and cost, the observer might want to stop earlier instead of inspecting all the available units. Let the process terminate at r2th unit where r12137 Examining the Perceptions of Religious Stakeholders Towards Religious Tourism Development
Authors: Sotiroula Liasidou, Katerina Pericleous, Zanete Garanti,
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Traveling for religious and pilgrimage purposes consists of an early-stage motivation for the historical development of tourism. Sacred places have become important attractions for local and foreign visitors, and many countries invest in the development of religious and pilgrimage tourism. Cyprus has a rich tradition as an important place for the establishment and diffusion of the Christian Orthodox Religion (Greek). Being considered the ‘island of Saints’, Cyprus sets strong foundations to be recognised as a spiritual destination of devotion for visitors interested in discovering the roots and the spiritual essence of the Christian Orthodox Religion. The paper elucidates on bringing together the fact of whether tourism in sacred places affects spirituality and religiosity. Thus, the aim is to consider the perceptions of the main religious stakeholders, including monastery abbots, in relation to the development of religious tourism. The aim of the study is fulfilled by incorporating questionnaires targeting the responses of the involved religious key players and stakeholders. The results of the study are indicative and provide an understanding in terms of religious tourism as an important product by interpreting the stance of religious stakeholders. In general, religious leaders support tourism in religious sites and argue that spirituality and holiness can be maintained as long there is a policy that is followed both by religious and tourism policymakers. Undoubtedly, establishing Cyprus as a religious tourism destination would bring many economic and social benefits.Keywords: religious tourism, pilgrimage, Cyprus, Christian Orthodox Religion, sacred places, monasteries
Procedia PDF Downloads 1482136 The Attitude and Willingness to Use Telecare for Arthritis Patients
Authors: Jui-Chen Huang
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Nowadays, the population is aging, the number of people who need to be taken care of is increased, but the manpower and funding are insufficient. Therefore, this study aims to explore the attitudes and willingness of arthritis patients to adopt telecare and to take a large medical institution in the central area of Taiwan as a sample hospital. A structured questionnaire (using the Likert five-point scale) was used to collect chronic patients over 20 years old as sample data, and a total of 500 valid questionnaires were effectively collected. The SPSS 18.0 statistical software was used for reliability analysis and independent sample t-test to explore the differences in attitudes and willingness to use telecare for arthritis patients and non-arthritic patients. The Cronbach's alpha value of this study questionnaire was above 0.94, showing good reliability. Arthritis patients and non-arthritic patients had statistically significant differences in attitudes toward telecare, while the willingness to use did not reach statistically significant differences. In addition, the average attitude and intention of arthritis patients for telecare are 3.38 and 3.41, respectively, indicating that arthritis patients have a certain degree of attitude and willingness to adopt telecare, which is worthy of follow-up research and practical industry push.Keywords: telecare, arthritis patients, attitudes, intention
Procedia PDF Downloads 1452135 Influence of Urban Fabric on Child’s Upbringing: A Comparative Analysis between Modern and Traditional City
Authors: Mohamed A. Tantawy, Nourelhoda A. Hussein, Moataz A. Mahrous
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New planning and city design theories are continuously debated and optimized for seeking efficiency and adequacy in economic and life quality aspects. Here, we examine the children-city relationship, to reflect on how modern and traditional cities affect the social climate. We adopt children as a proper caliber for urbanism, as for their very young age, they are independent and attached to family. Their fragility offers a chance to gauge how various urban settings directly affect their feeling of safety, containment, and their perception of belonging for home territory. The importance of street play for the child development process is discussed thoroughly. The authority they have on their play (when and what to play) pushes us to our conclusion. A mediocre built environment characterized by spontaneity and human-scale semi-private urban spaces, is irreplaceable by a perfectly designed far away playgrounds. Street play has a huge role in empowering children for a gradual engagement with grown-ups’ urban flow.Keywords: child's psychology, social activity, street play, urban fabric
Procedia PDF Downloads 3182134 A Study of Evolutional Control Systems
Authors: Ti-Jun Xiao, Zhe Xu
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Controllability is one of the fundamental issues in control systems. In this paper, we study the controllability of second order evolutional control systems in Hilbert spaces with memory and boundary controls, which model dynamic behaviors of some viscoelastic materials. Transferring the control problem into a moment problem and showing the Riesz property of a family of functions related to Cauchy problems for some integrodifferential equations, we obtain a general boundary controllability theorem for these second order evolutional control systems. This controllability theorem is applicable to various concrete 1D viscoelastic systems and recovers some previous related results. It is worth noting that Riesz sequences can be used for numerical computations of the control functions and the identification of new Riesz sequence is of independent interest for the basis-function theory. Moreover, using the Riesz sequences, we obtain the existence and uniqueness of (weak) solutions to these second order evolutional control systems in Hilbert spaces. Finally, we derive the exact boundary controllability of a viscoelastic beam equation, as an application of our abstract theorem.Keywords: evolutional control system, controllability, boundary control, existence and uniqueness
Procedia PDF Downloads 2262133 Dynamic Analysis of a Moderately Thick Plate on Pasternak Type Foundation under Impact and Moving Loads
Authors: Neslihan Genckal, Reha Gursoy, Vedat Z. Dogan
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In this study, dynamic responses of composite plates on elastic foundations subjected to impact and moving loads are investigated. The first order shear deformation (FSDT) theory is used for moderately thick plates. Pasternak-type (two-parameter) elastic foundation is assumed. Elastic foundation effects are integrated into the governing equations. It is assumed that plate is first hit by a mass as an impact type loading then the mass continues to move on the composite plate as a distributed moving loading, which resembles the aircraft landing on airport pavements. Impact and moving loadings are modeled by a mass-spring-damper system with a wheel. The wheel is assumed to be continuously in contact with the plate after impact. The governing partial differential equations of motion for displacements are converted into the ordinary differential equations in the time domain by using Galerkin’s method. Then, these sets of equations are solved by using the Runge-Kutta method. Several parameters such as vertical and horizontal velocities of the aircraft, volume fractions of the steel rebar in the reinforced concrete layer, and the different touchdown locations of the aircraft tire on the runway are considered in the numerical simulation. The results are compared with those of the ABAQUS, which is a commercial finite element code.Keywords: elastic foundation, impact, moving load, thick plate
Procedia PDF Downloads 3182132 Optimization of Pretreatment Process of Napier Grass for Improved Sugar Yield
Authors: Shashikant Kumar, Chandraraj K.
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Perennial grasses have presented interesting choices in the current demand for renewable and sustainable energy sources to alleviate the load of the global energy problem. The perennial grass Napier grass (Pennisetum purpureum Schumach) is a promising feedstock for the production of cellulosic ethanol. The conversion of biomass into glucose and xylose is a crucial stage in the production of bioethanol, and it necessitates optimal pretreatment. Alkali treatment, among the several pretreatments available, effectively reduces lignin concentration and crystallinity of cellulose. Response surface methodology was used to optimize the alkali pretreatment of Napier grass for maximal reducing sugar production. The combined effects of three independent variables, viz. sodium hydroxide concentration, temperature, and reaction time, were studied. A second-order polynomial equation was used to fit the observed data. Maximum reducing sugar (590.54 mg/g) was obtained under the following conditions: 1.6 % sodium hydroxide, a reaction period of 30 min., and 120˚C. The results showed that Napier grass is a desirable feedstock for bioethanol production.Keywords: Napier grass, optimization, pretreatment, sodium hydroxide
Procedia PDF Downloads 5132131 Company-Independent Standardization of Timber Construction to Promote Urban Redensification of Housing Stock
Authors: Andreas Schweiger, Matthias Gnigler, Elisabeth Wieder, Michael Grobbauer
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Especially in the alpine region, available areas for new residential development are limited. One possible solution is to exploit the potential of existing settlements. Urban redensification, especially the addition of floors to existing buildings, requires efficient, lightweight constructions with short construction times. This topic is being addressed in the five-year Alpine Building Centre. The focus of this cooperation between Salzburg University of Applied Sciences and RSA GH Studio iSPACE is on transdisciplinary research in the fields of building and energy technology, building envelopes and geoinformation, as well as the transfer of research results to industry. One development objective is a system of wood panel system construction with a high degree of prefabrication to optimize the construction quality, the construction time and the applicability for small and medium-sized enterprises. The system serves as a reliable working basis for mastering the complex building task of redensification. The technical solution is the development of an open system in timber frame and solid wood construction, which is suitable for a maximum two-story addition of residential buildings. The applicability of the system is mainly influenced by the existing building stock. Therefore, timber frame and solid timber construction are combined where necessary to bridge large spans of the existing structure while keeping the dead weight as low as possible. Escape routes are usually constructed in reinforced concrete and are located outside the system boundary. Thus, within the framework of the legal and normative requirements of timber construction, a hybrid construction method for redensification created. Component structure, load-bearing structure and detail constructions are developed in accordance with the relevant requirements. The results are directly applicable in individual cases, with the exception of the required verifications. In order to verify the practical suitability of the developed system, stakeholder workshops are held on the one hand, and the system is applied in the planning of a two-storey extension on the other hand. A company-independent construction standard offers the possibility of cooperation and bundling of capacities in order to be able to handle larger construction volumes in collaboration with several companies. Numerous further developments can take place on the basis of the system, which is under open license. The construction system will support planners and contractors from design to execution. In this context, open means publicly published and freely usable and modifiable for own use as long as the authorship and deviations are mentioned. The companies are provided with a system manual, which contains the system description and an application manual. This manual will facilitate the selection of the correct component cross-sections for the specific construction projects by means of all component and detail specifications. This presentation highlights the initial situation, the motivation, the approach, but especially the technical solution as well as the possibilities for the application. After an explanation of the objectives and working methods, the component and detail specifications are presented as work results and their application.Keywords: redensification, SME, urban development, wood building system
Procedia PDF Downloads 1132130 An Epistemic Approach to Confidence Through Objectivity in Assurance of Safety-Critical Complex Systems
Authors: Odd Ivar Haugen
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This paper presents a framework for assessing the objectivity of the assurance effort for safety-critical complex systems. Assurance is the process of building justified confidence that a system will behave as expected. Objectivity, as a property of the inquiry process, is key to generating this confidence. The framework identifies three main dimensions of objectivity: the methods and processes used to generate system and assurance artefacts, the reasoning and values underlying those artefacts, and the social processes that enable agreement on their validity. Each dimension contributes to overall objectivity, however, not as a set of independent dimensions. Objectivity is not a binary but a matter of degree, and different levels are required depending on the criticality of the system. The framework provides guidance on how to apply the concept of objectivity to different aspects of the assurance effort, from identifying stakeholders and their concerns to communicating risk. Requirement identification and refinement, verification, and risk communication are illustrations of its use in various assurance activities. Overall, this work offers a systematic approach to building justified confidence in the safety of complex engineered systems.Keywords: assurance, objectivity, risk, uncertainty, knowledge, system safety
Procedia PDF Downloads 192129 Artificially Intelligent Context Aware Personal Computer Assistant (ACPCA)
Authors: Abdul Mannan Akhtar
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In this paper a novel concept of a self learning smart personalized computer assistant (ACPCA) is established which is a context aware system. Based on user habits, moods, and other routines/situational reactions the system will manage various services and suggestions at appropriate times including what schedule to follow, what to watch, what software to be used, what should be deleted etc. This system will utilize a hybrid fuzzyNeural model to predict what the user will do next and support his actions. This will be done by establishing fuzzy sets of user activities, choices, preferences etc. and utilizing their combinations to predict his moods and immediate preferences. Various application of context aware systems exist separately e.g. on certain websites for music or multimedia suggestions but a personalized autonomous system that could adapt to user’s personality does not exist at present. Due to the novelty and massiveness of this concept, this paper will primarily focus on the problem establishment, product features and its functionality; however a small mini case is also implemented on MATLAB to demonstrate some of the aspects of ACPCA. The mini case involves prediction of user moods, activity, routine and food preference using a hybrid fuzzy-Neural soft computing technique.Keywords: context aware systems, APCPCA, soft computing techniques, artificial intelligence, fuzzy logic, neural network, mood detection, face detection, activity detection
Procedia PDF Downloads 4662128 Authority and Function of Administrative Organs According to the Constitution: A Construction of Democracy in the Administrative Law of Indonesia
Authors: Andhika Danesjvara, Nur Widyastanti
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The constitution regulates the forms, types, and powers of sState organs in a government. The powers of the organs are then regulated in more detail in the legislation. One of these organs is a government organ, headed by a president or by another name that serves as the main organizer of government. The laws and regulations will govern how the organs of government shall exercise their authority and functions. In a modern state, the function of enacting laws or called executive power does not exercise the functions of government alone, but there are other organs that help the government run the country. These organs are often called government agencies, government accelerating bodies, independent regulatory bodies, commissions, councils or other similar names. The legislation also limits the power of officials within the organs to keep from abusing its authority. The main question in this paper is whether organs are the implementation of a democratic country, or as a form of compromise with the power of stakeholders. It becomes important to see how the administrative organs perform their functions. The administrative organs that are bound by government procedures work in the public service; therefore the next question is how far the function of public service is appropriate and not contradictory to the constitution.Keywords: administrative organs, constitution, democracy, government
Procedia PDF Downloads 3142127 Factors Affecting the Effective Management of the Employee Welfare Fund at the Department of Labour Protection and Welfare
Authors: Nareerut Rodwring
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The purposes of this research were to study the current problems of the management of welfare fund at the department of labor protection and welfare, to study important factors affecting the management of welfare fund at the department of labor protection and welfare, to study major influences of the management of welfare fund at the department of labor protection and welfare, and finally to propose the proper guidelines for the management of welfare fund at the department of labor protection and welfare. This research study utilized the information from document, laws, rules, and regulations of the government, handbook for welfare, and government policy in the past. Moreover, the qualitative research was conducted by retrieving insight information from key informants, 15 persons for the committee of welfare employees, and 10 persons from a high level of management in the welfare area, academics, and experts. In terms of quantitative method, the study covers all 76 provinces and 10 areas of Bangkok. Independent variables included strategy, structure, shared value, system, whereas the dependent variables included the management factors such as speed, punctuation, and quality of work.Keywords: strategy, welfare, labor protection, management
Procedia PDF Downloads 1852126 Estimation of the Temperatures in an Asynchronous Machine Using Extended Kalman Filter
Authors: Yi Huang, Clemens Guehmann
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In order to monitor the thermal behavior of an asynchronous machine with squirrel cage rotor, a 9th-order extended Kalman filter (EKF) algorithm is implemented to estimate the temperatures of the stator windings, the rotor cage and the stator core. The state-space equations of EKF are established based on the electrical, mechanical and the simplified thermal models of an asynchronous machine. The asynchronous machine with simplified thermal model in Dymola is compiled as DymolaBlock, a physical model in MATLAB/Simulink. The coolant air temperature, three-phase voltages and currents are exported from the physical model and are processed by EKF estimator as inputs. Compared to the temperatures exported from the physical model of the machine, three parts of temperatures can be estimated quite accurately by the EKF estimator. The online EKF estimator is independent from the machine control algorithm and can work under any speed and load condition if the stator current is nonzero current system.Keywords: asynchronous machine, extended Kalman filter, resistance, simulation, temperature estimation, thermal model
Procedia PDF Downloads 2882125 Electronic and Optical Properties of Orthorhombic NdMnO3 with the Modified Becke-Johnson Potential
Authors: B. Bouadjemi, S. Bentata, T. Lantri, A. Abbad, W. Benstaali, A. Zitouni, S. Cherid
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We investigate the electronic structure, magnetic and optical properties of the orthorhombic NdMnO3 through density-functional-theory (DFT) calculations using both generalized gradient approximation GGA and GGA+U approaches, the exchange and correlation effects are taken into account by an orbital independent modified Becke Johnson (MBJ). The predicted band gaps using the MBJ exchange approximation show a significant improvement over previous theoretical work with the common GGA and GGA+U very closer to the experimental results. Band gap dependent optical parameters like dielectric constant, index of refraction, absorption coefficient, reflectivity and conductivity are calculated and analyzed. We find that when using MBJ we have obtained better results for band gap of NdMnO3 than in the case of GGA and GGA+U. The values of band gap founded in this work by MBJ are in a very good agreement with corresponding experimental values compared to other calculations. This comprehensive theoretical study of the optoelectronic properties predicts that this material can be effectively used in optical devices.Keywords: DFT, optical properties, absorption coefficient, strong correlation, MBJ, orthorhombic NdMnO3, optoelectronic
Procedia PDF Downloads 9142124 Dual-Band Microwave Metamaterial Absorber Using Modified Circular Ring Resonator for Sensor Applications
Authors: Ramesh Amugothu, Vakula Damera, Narasimha Sarma N. V. S.
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This study presents a dual-band metamaterial microwave absorber that functions at frequencies of 3.5 GHz and 5.7 GHz. The design comprises modified ring and rectangular patch resonators fabricated on an FR4 dielectric substrate with a ground layer beneath it, emphasizing simplicity. Each absorption frequency is independent and can be individually adjusted by altering the dimensions of the respective resonator structures. The unit cell of the absorber is simulated and optimized parametrically using high-frequency structure simulator (HFSS) software. The mechanism behind the absorption is examined through surface current analysis as well as the symmetric model method. The absorber demonstrates over 97% absorption at both resonant frequencies and is shown to be suitable for sensing applications related to dielectric constant measurement. With its straightforward design, wide-angle acceptance, and polarization-insensitive characteristics, the proposed absorber is likely to be beneficial for both absorption and sensing purposes.Keywords: absorption, dielectric permittivity, metamaterials, metasurfaces, resonant structures, sensor devices
Procedia PDF Downloads 16