Search results for: structural induction
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4815

Search results for: structural induction

4635 The Antioxidant and Antinociceptive Effects of Curcumin in Experimentally Induced Pain in Rats

Authors: Valeriu Mihai But, Sorana Daniela Bolboacă, Adriana Elena Bulboacă

Abstract:

The nutraceutical compound Curcumin (Curcuma longa L.) is known for its anti-inflammatory, anti-cancer, and antioxidant effects. This study aimed to evaluate the antioxidative and analgesic effects of Curcumin (CC) compared to Tramadol (T) in chemical-induced nociceptive pain in rats. Thirty-five rats were randomly divided into five groups of seven rats each and were treated as follows: C group (control group): treated with saline solution 0.9%, (1 ml, i.p. administration), ethanoic acid (EA) group: pretreated with saline solution 0.9% - 30 min before EA nociceptive pain induction, (1 ml, i.p. administration), T group: pretreated with Tramadol, 10 mg/kg body weight (bw), i.p. administration - 30 min before EA nociceptive pain induction, CC1-group: pretreated with 1 mg/100g bw Curcumin i.p. administration - 2 days before EA pain induction and CC2-group: pretreated with Curcumin 2 mg/100g bw i.p. administration - 2 days before EA nociceptive pain induction. The following oxidative stress parameters were assessed: malondialdehyde (MDA), nitric oxide (NOx), total oxidative status (TOS), total antioxidative capacity (TAC), and thiol (Th). The antalgic activity was measured by the ethanoic acid writhing test. Treatment with Curcumin, both 1 mg/100g bw, and 2 mg/100g bw, showed significant differences as compared with the control group (p<0.001) regarding malondialdehyde (MDA), nitric oxide (NOx), and total oxidative status (TOS) oxidative biomarkers. Pretreatment with 2 mg/100g bw of Curcumin presented a significant decrease in MDA values compared with Tramadol (p<0.001). The TAC significantly increased in pretreatment with Curcumin compared with group control. (p<0.001) The nociceptive response to EA was significantly reduced in Curcumin and Tramadol groups. Treatment with Curcumin at a higher concentration was more effective. In an experimental pain model, this study demonstrates an important antioxidant and antinociceptive activity of Curcumin comparable with Tramadol treatment.

Keywords: curcumin, nociception, oxidative stress, pain

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4634 Weight Regulation Mechanism on Bridges

Authors: S. Siddharth, Saravana Kumar

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All Metros across the world tend to have a large number of bridges and there have been concerns about the safety of these bridges. As the traffic in most cities in India is heterogeneous, Trucks and Heavy vehicles traverse on our roads on an everyday basis this will lead to structural damage on the long run. All bridges are designed with a maximum Load limit and this limit is seldom checked. We have hence come up with an idea to check the load of all the vehicles entering the bridge and block the bridge with barricades if the vehicle surpasses the maximum load , this is done to catch hold of the perpetrators. By doing this we can avoid further structural damage and also provide an effective way to enforce the law. If our solution is put in place structural damage and accidents would be reduced to a great deal and it would also make the law enforcement job easier.

Keywords: heterogeneous, structural, load, law, heavy, vehicles

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4633 Scope of Samarium Content on Microstructural and Structural Properties of Potassium-Sodium Niobate (KNN) Based Ceramics

Authors: Geraldine Giraldo

Abstract:

In the research of advanced materials, ceramics based on KNN are an important topic, especially for multifunctional applications. In this work, the physical, structural, and microstructural properties of the (KNN-CaLi-xSm) system were analyzed by varying the concentration of samarium, which was prepared using the conventional solid-state reaction method by mixing oxides. It was found that the increase in Sm+3 concentration led to higher porosity in the sample and, consequently, a decrease in density, which is attributed to the structural vacancies at the A-sites of the perovskite-type structure of the ceramic system. In the structural analysis, a coexistence of Tetragonal (T) and Orthorhombic (O) phases were observed at different rare-earth ion contents, with a higher content of the T phase at xSm=0.010. Furthermore, the structural changes in the calcined powders at different temperatures were studied using the results of DTA-TG, which allowed for the analysis of the system's composition. It was found that the lowest total decomposition temperature occurred when xSm=0.010 at 770°C.

Keywords: perovskite, piezoelectric, multifunctional, Structure, ceramic

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4632 Backstepping Controller for a Variable Wind Speed Energy Conversion System Based on a DFIG

Authors: Sara Mensou, Ahmed Essadki, Issam Minka, Tamou Nasser, Badr Bououlid Idrissi

Abstract:

In this paper we present a contribution for the modeling and control of wind energy conversion system based on a Doubly Fed Induction Generator (DFIG). Since the wind speed is random the system has to produce an optimal electrical power to the Network and ensures important strength and stability. In this work, the Backstepping controller is used to control the generator via two converter witch placed a DC bus capacitor and connected to the grid by a Filter R-L, in order to optimize capture wind energy. All is simulated and presented under MATLAB/Simulink Software to show performance and robustness of the proposed controller.

Keywords: wind turbine, doubly fed induction generator, MPPT control, backstepping controller, power converter

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4631 Harnessing Nigeria's Forestry Potential for Structural Applications: Structural Reliability of Nigerian Grown Opepe Timber

Authors: J. I. Aguwa, S. Sadiku, M. Abdullahi

Abstract:

This study examined the structural reliability of the Nigerian grown Opepe timber as bridge beam material. The strength of a particular specie of timber depends so much on some factors such as soil and environment in which it is grown. The steps involved are collection of the Opepe timber samples, seasoning/preparation of the test specimens, determination of the strength properties/statistical analysis, development of a computer programme in FORTRAN language and finally structural reliability analysis using FORM 5 software. The result revealed that the Nigerian grown Opepe is a reliable and durable structural bridge beam material for span of 5000mm, depth of 400mm, breadth of 250mm and end bearing length of 150mm. The probabilities of failure in bending parallel to the grain, compression perpendicular to the grain, shear parallel to the grain and deflection are 1.61 x 10-7, 1.43 x 10-8, 1.93 x 10-4 and 1.51 x 10-15 respectively. The paper recommends establishment of Opepe plantation in various Local Government Areas in Nigeria for structural applications such as in bridges, railway sleepers, generation of income to the nation as well as creating employment for the numerous unemployed youths.

Keywords: bending and deflection, bridge beam, compression, Nigerian Opepe, shear, structural reliability

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4630 Non-Chronological Approach in Crane Girder and Composite Steel Beam Installation: Case Study

Authors: Govindaraj Ramanathan

Abstract:

The time delay and the structural stability are major issues in big size projects due to several factors. Improper planning and poor coordination lead to delay in construction, which sometimes result in reworking or rebuilding. This definitely increases the cost and time of project. This situation stresses the structural engineers to plan out of the limits of contemporary technology utilizing non-chronological approach with creative ideas. One of the strategies to solve this issue is through structural integrity solutions in a cost-effective way. We have faced several problems in a project worth 470 million USD, and one such issue is crane girder installation with composite steel beams. We have applied structural integrity approach with the proper and revised planning schedule to solve the problem efficiently with minimal expenses.

Keywords: construction management, delay, non-chronological approach, composite beam, structural integrity

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4629 Investigating the Experiences of Higher Education Academics on the Blended Approach Used during the Induction Course

Authors: Ann-May Marais

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South African higher education institutions are following the global adoption of a blended approach to teaching and learning. Blended learning is viewed as a transformative teaching-learning approach, as it provides students with the optimum experience by mixing the best of face-to-face and online learning. Although academics realise the benefits of blended learning, they find it challenging and time-consuming to implement blended strategies. Professional development is a critical component of the adoption of higher education teaching-learning approaches. The Institutional course for higher education academics offered at a South African University was designed in a blended model, implemented and evaluated. This paper reports on a study that investigated the experiences of academics on the blended approach used during the induction course. A qualitative design-based research methodology was employed, and data was collected using participant feedback and document analysis. The data gathered from each of the four ICNL offerings were used to inform the design of the next course. Findings indicated that lecturers realised that blended learning could cater to student diversity, different learning styles, engagement, and innovation. Furthermore, it emerged that the course has to cater for diversity in technology proficiency and readiness of participants. Participants also require ongoing support in technology usage and discipline-specific blended learning workshops. This paper contends that the modelling of a blended approach to professional development can be an effective way to motivate academics to apply blended learning in their teaching-learning experiences.

Keywords: blended learning, professional development, induction course, integration of technology

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4628 Apoptotic Induction Ability of Harmalol and Its Binding: Biochemical and Biophysical Perspectives

Authors: Kakali Bhadra

Abstract:

Harmalol administration caused remarkable reduction in proliferation of HepG2 cells with GI50 of 14.2 mM, without showing much cytotoxicity in embryonic liver cell line, WRL-68. Data from circular dichroism and differential scanning calorimetric analysis of harmalol-CT DNA complex shows conformational changes with prominent CD perturbation and stabilization of CT DNA by 8 oC. Binding constant and stoichiometry was also calculated using the above biophysical techniques. Further, dose dependent apoptotic induction ability of harmalol was studied in HepG2 cells using different biochemical assays. Generation of ROS, DNA damage, changes in cellular external and ultramorphology, alteration of membrane, formation of comet tail, decreased mitochondrial membrane potential and a significant increase in Sub Go/G1 population made the cancer cell, HepG2, prone to apoptosis. Up regulation of p53 and caspase 3 further indicated the apoptotic role of harmalol.

Keywords: apoptosis, beta carboline alkaloid, comet assay, cytotoxicity, ROS

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4627 The Structural Pattern: An Event-Related Potential Study on Tang Poetry

Authors: ShuHui Yang, ChingChing Lu

Abstract:

Measuring event-related potentials (ERPs) has been fundamental to our understanding of how people process language. One specific ERP component, a P600, has been hypothesized to be associated with syntactic reanalysis processes. We, however, propose that the P600 is not restricted to reanalysis processes, but is the index of the structural pattern processing. To investigate the structural pattern processing, we utilized the effects of stimulus degradation in structural priming. To put it another way, there was no P600 effect if the structure of the prime was the same with the structure of the target. Otherwise, there would be a P600 effect if the structure were different between the prime and the target. In the experiment, twenty-two participants were presented with four sentences of Tang poetry. All of the first two sentences, being prime, were conducted with SVO+VP. The last two sentences, being the target, were divided into three types. Type one of the targets was SVO+VP. Type two of the targets was SVO+VPVP. Type three of the targets was VP+VP. The result showed that both of the targets, SVO+VPVP and VP+VP, elicited positive-going brainwave, a P600 effect, at 600~900ms time window. Furthermore, the P600 component was lager for the target’ VP+VP’ than the target’ SVO+VPVP’. That meant the more dissimilar the structure was, the lager the P600 effect we got. These results indicate that P600 was the index of the structure processing, and it would affect the P600 effect intensity with the degrees of structural heterogeneity.

Keywords: ERPs, P600, structural pattern, structural priming, Tang poetry

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4626 Progressive Structural Capacity Loss Assessment

Authors: M. Zain, Thaung H. Aung, Naveed Anwar

Abstract:

During the service life, a structure may experience extreme loading conditions. The current study proposes a new methodology that covers the effect of uncertainty involved in gravity loadings on key structural elements of new and complex structures by emphasizing on a very realistic assumption that allows the 'Performance-Based Assessment' to be executed on the structure against the gravity loadings. The methodology does not require the complete removal of an element, instead, it permits the incremental reduction in the capacity of key structural elements and preserves the same stiffness of the member in each case of capacity loss. To demonstrate the application of the proposed methodology, a 13 story complex structure is selected that comprises of a diverse structural configuration. The results ensure the structural integrity against the applied gravity loadings, as well as the effectiveness of the proposed methodology.

Keywords: force-deformation relationship, gravity loading, incremental capacity reduction, multi-linear plastic link element, SAP2000, stiffness

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4625 Hybrid Approximate Structural-Semantic Frequent Subgraph Mining

Authors: Montaceur Zaghdoud, Mohamed Moussaoui, Jalel Akaichi

Abstract:

Frequent subgraph mining refers usually to graph matching and it is widely used in when analyzing big data with large graphs. A lot of research works dealt with structural exact or inexact graph matching but a little attention is paid to semantic matching when graph vertices and/or edges are attributed and typed. Therefore, it seems very interesting to integrate background knowledge into the analysis and that extracted frequent subgraphs should become more pruned by applying a new semantic filter instead of using only structural similarity in graph matching process. Consequently, this paper focuses on developing a new hybrid approximate structuralsemantic graph matching to discover a set of frequent subgraphs. It uses simultaneously an approximate structural similarity function based on graph edit distance function and a possibilistic vertices similarity function based on affinity function. Both structural and semantic filters contribute together to prune extracted frequent set. Indeed, new hybrid structural-semantic frequent subgraph mining approach searches will be suitable to be applied to several application such as community detection in social networks.

Keywords: approximate graph matching, hybrid frequent subgraph mining, graph mining, possibility theory

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4624 Long-Term Mechanical and Structural Properties of Metakaolin-Based Geopolymers

Authors: Lenka Matulova

Abstract:

Geopolymers are alumosilicate materials that have long been studied. Despite this fact, little is known about the long-term stability of geopolymer mechanical and structural properties, so crucial for their successful industrial application. To improve understanding, we investigated the effect of four different types of environments on the mechanical and structural properties of a metakaolin-based geopolymer (MK GP). The MK GP samples were stored in laboratory conditions (control samples), in water at 20 °C, in water at 80 °C, and outside exposed to the weather. Compressive and tensile strengths were measured after 28, 56, 90, and 360 days. In parallel, structural properties were analyzed using XRD, SEM, and mercury intrusion porosimetry. Whereas the mechanical properties of the samples in laboratory conditions and in 20 °C water were stable, the mechanical properties of the outdoor samples and the samples 80 °C water decreased noticeably after 360 days. Structural analyses were focused on changes in sample microstructure (developing microcrack network, porosity) and identifying zeolites, the presence of which would indicate detrimental processes in the structure that can change it from amorphous to crystalline. No zeolites were found during the 360-day period in MK GP samples, but the reduction in mechanical properties coincided with a developing network of microcracks and changes in pore size distribution.

Keywords: geopolymer, long-term properties, mechanical properties, metakaolin, structural properties

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4623 Advancements in Truss Design for High-Performance Facades and Roof System: A Structural Analysis

Authors: Milind Anurag

Abstract:

This study investigates cutting-edge truss design improvements, which are specifically adapted to satisfy the structural demands and difficulties associated with high-performance facades and roofs in modern architectural environments. With a growing emphasis on sustainability, energy efficiency, and eye-catching architectural aesthetics, the structural components that support these characteristics play an important part in attaining the right balance of form and function. The paper seeks to contribute to the evolution of truss design methods by combining data from these investigations, giving significant insights for architects, engineers, and researchers interested in the creation of high-performance building envelopes. The findings of this study are meant to inform future design standards and practices, promoting the development of structures that seamlessly integrate architectural innovation with structural robustness and environmental responsibility.

Keywords: truss design, high-performance, facades, finite element analysis, structural efficiency

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4622 Redundancy Component Matrix and Structural Robustness

Authors: Xinjian Kou, Linlin Li, Yongju Zhou, Jimian Song

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We introduce the redundancy matrix that expresses clearly the geometrical/topological configuration of the structure. With the matrix, the redundancy of the structure is resolved into redundant components and assigned to each member or rigid joint. The values of the diagonal elements in the matrix indicates the importance of the corresponding members or rigid joints, and the geometrically correlations can be shown with the non-diagonal elements. If a member or rigid joint failures, reassignment of the redundant components can be calculated with the recursive method given in the paper. By combining the indexes of reliability and redundancy components, we define an index concerning the structural robustness. To further explain the properties of the redundancy matrix, we cited several examples of statically indeterminate structures, including two trusses and a rigid frame. With the examples, some simple results and the properties of the matrix are discussed. The examples also illustrate that the redundancy matrix and the relevant concepts are valuable in structural safety analysis.

Keywords: Structural Robustness, Structural Reliability, Redundancy Component, Redundancy Matrix

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4621 The Influence of Structural Disorder and Phonon on Metal-To-Insulator Transition of VO₂

Authors: Sang-Wook Han, In-Hui Hwang, Zhenlan Jin, Chang-In Park

Abstract:

We used temperature-dependent X-Ray absorption fine structure (XAFS) measurements to examine the local structural properties around vanadium atoms at the V K edge from VO₂ films. A direct comparison of simultaneously-measured resistance and XAFS from the VO₂ films showed that the thermally-driven structural phase transition (SPT) occurred prior to the metal-insulator transition (MIT) during heating, whereas these changed simultaneously during cooling. XAFS revealed a significant increase in the Debye-Waller factors of the V-O and V-V pairs in the {111} direction of the R-phase VO₂ due to the phonons of the V-V arrays along the direction in a metallic phase. A substantial amount of structural disorder existing on the V-V pairs along the c-axis in both M₁ and R phases indicates the structural instability of V-V arrays in the axis. The anomalous structural disorder observed on all atomic sites at the SPT prevents the migration of the V 3d¹ electrons, resulting in a Mott insulator in the M₂-phase VO₂. The anomalous structural disorder, particularly, at vanadium sites, effectively affects the migration of metallic electrons, resulting in the Mott insulating properties in M₂ phase and a non-congruence of the SPT, MIT, and local density of state. The thermally-induced phonons in the {111} direction assist the delocalization of the V 3d¹ electrons in the R phase VO₂ and the electrons likely migrate via the V-V array in the {111} direction as well as the V-V dimerization along the c-axis. This study clarifies that the tetragonal symmetry is essentially important for the metallic phase in VO₂.

Keywords: metal-insulator transition, XAFS, VO₂, structural-phase transition

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4620 Influence of Thickness on Electrical and Structural Properties of Zinc Oxide (ZnO) Thin Films Prepared by RF Sputtering Technique

Authors: M. Momoh, S. Abdullahi, A. U. Moreh

Abstract:

Zinc oxide (ZnO) thin films were prepared on corning (7059) glass substrates at a thickness of 75.5 and 130.5 nm by RF sputtering technique. The deposition was carried out at room temperature after which the samples were annealed in open air at 150°C. The electrical and structural properties of these films were studied. The electrical properties of the films were monitored by four-point probe method while the structural properties were studied by X-ray diffraction (XRD). It was found that the electrical resistance of the films decreases with increase in the thickness of the films. The XRD analysis of the films showed that the films have a peak located at 34.31°-34.35° with hkl (002). Other parameters calculated include the stress (σ) and the grain size (D).

Keywords: electrical properties, film thickness, structural properties, zinc oxide

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4619 Seismic Considerations in Case Study of Kindergarten Building Design: Ensuring Safety and Structural Integrity

Authors: Al-Naqdi Ibtehal Abdulmonem, Hameed Reem Majeed

Abstract:

Kindergarten buildings are essential for early childhood education, providing a secure environment for children's development. However, they are susceptible to seismic forces, which can endanger occupants during earthquakes. This article emphasizes the importance of conducting thorough seismic analysis and implementing proper structural design to protect the well-being of children, staff, and visitors. By prioritizing structural integrity and considering functional requirements, engineers can mitigate risks associated with seismic events. The use of specialized software like ETABS is crucial for designing earthquake-resistant kindergartens. An analysis using ETABS software compared the structural performance of a single-story kindergarten in Iraq's Ministry of Education, designed with and without seismic considerations. The analysis aimed to assess the impact of seismic design on structural integrity and safety. The kindergarten was designed with seismic considerations, including moment frames. In contrast, the same kindergarten was analyzed without seismic effects, revealing a lack of structural elements to resist lateral forces, rendering it vulnerable to structural failure during an earthquake. Maximum major shear increased over 4 times and over 5 times for bending moment in the kindergarten designed with seismic considerations induced by lateral loads and seismic forces. This component of shear force is vital for designing elements to resist lateral loads and ensure structural stability.

Keywords: seismic analysis, structural design, lateral loads, earthquake resistance, major shear, ETABS

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4618 Structural Reliability of Existing Structures: A Case Study

Authors: Z. Sakka, I. Assakkaf, T. Al-Yaqoub, J. Parol

Abstract:

A reliability-based methodology for the analysis assessment and evaluation of reinforced concrete structural elements of concrete structures is presented herein. The results of the reliability analysis and assessment for structural elements are verified by the results obtained from the deterministic methods. The analysis outcomes of reliability-based analysis are compared against the safety limits of the required reliability index β according to international standards and codes. The methodology is based on probabilistic analysis using reliability concepts and statistics of the main random variables that are relevant to the subject matter, and for which they are to be used in the performance-function equation(s) related to the structural elements under study. These methodology techniques can result in reliability index β, which is commonly known as the reliability index or reliability measure value that can be utilized to assess and evaluate the safety, human risk, and functionality of the structural component. Also, these methods can result in revised partial safety factor values for certain target reliability indices that can be used for the purpose of redesigning the reinforced concrete elements of the building and in which they could assist in considering some other remedial actions to improve the safety and functionality of the member.

Keywords: structural reliability, concrete structures, FORM, Monte Carlo simulation

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4617 Application of Matrix Converter for the Power Control of a DFIG-Based Wind Turbine

Authors: E. Bounadja, M. O. Mahmoudi, A. Djahbar, Z. Boudjema

Abstract:

This paper presents a control approach of the doubly fed induction generator (DFIG) in conjunction with a direct AC-AC matrix converter used in generating mode. This device is intended to be implemented in a variable speed wind energy conversion system connected to the grid. Firstly, we developed a model of matrix converter, controlled by the Venturini modulation technique. In order to control the power exchanged between the stator of the DFIG and the grid, a control law is synthesized using a high order sliding mode controller. The use of this method provides very satisfactory performance for the DFIG control. The overall strategy has been validated on a 2-MW wind turbine driven a DFIG using the Matlab/Simulink.

Keywords: doubly fed induction generator (DFIG), matrix converter, high-order sliding mode controller, wind energy

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4616 Integration of Virtual Learning of Induction Machines for Undergraduates

Authors: Rajesh Kumar, Puneet Aggarwal

Abstract:

In context of understanding problems faced by undergraduate students while carrying out laboratory experiments dealing with high voltages, it was found that most of the students are hesitant to work directly on machine. The reason is that error in the circuitry might lead to deterioration of machine and laboratory instruments. So, it has become inevitable to include modern pedagogic techniques for undergraduate students, which would help them to first carry out experiment in virtual system and then to work on live circuit. Further advantages include that students can try out their intuitive ideas and perform in virtual environment, hence leading to new research and innovations. In this paper, virtual environment used is of MATLAB/Simulink for three-phase induction machines. The performance analysis of three-phase induction machine is carried out using virtual environment which includes Direct Current (DC) Test, No-Load Test, and Block Rotor Test along with speed torque characteristics for different rotor resistances and input voltage, respectively. Further, this paper carries out computer aided teaching of basic Voltage Source Inverter (VSI) drive circuitry. Hence, this paper gave undergraduates a clearer view of experiments performed on virtual machine (No-Load test, Block Rotor test and DC test, respectively). After successful implementation of basic tests, VSI circuitry is implemented, and related harmonic distortion (THD) and Fast Fourier Transform (FFT) of current and voltage waveform are studied.

Keywords: block rotor test, DC test, no load test, virtual environment, voltage source inverter

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4615 Structural Safety Assessment of Transmission Tower with High-Low Legs

Authors: Chi-Rung Jiang, Chun-Chung Chen, Sheng-Yuan Shiao, Fang-Yao Yeh

Abstract:

Transmission lines are essential for power systems which play a significant role in a city for the development of infrastructures. Once a tower on the transmission line is damaged or becomes unstable, small-scale transmission tower damage might cause a large-scale electric power failure, and consequently, the enormous economic losses will occur. This paper assesses the structural safety and considers the impact of earthquakes and winds, presents a preliminary study of transmission tower with high-low legs by building structural analysis models of towers. The result shows that the high-low legs towers do have some structural characteristics need to be considered, such as the length of the difference of high legs and low legs should be restricted and the deployment direction of legs must be carefully planned during the design of transmission towers. The outcome of this study is beneficial to power systems authorities.

Keywords: power transition tower, structural analysis, high-low legs, safety assessment

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4614 Lessons from Vernacular Architecture for Lightweight Construction

Authors: Alireza Taghdiri, Sara Ghanbarzade Ghomi

Abstract:

With the gravity load reduction in the structural and non-structural components, the lightweight construction will be achieved as well as the improvement of efficiency and functional specifications. The advantages of lightweight construction can be examined in two levels. The first is the mass reduction of load bearing structure which results in increasing internal useful space and the other one is the mass reduction of building which decreases the effects of seismic load as a result. In order to achieve this goal, the essential building materials specifications and also optimum load bearing geometry of structural systems and elements have to be considered, so lightweight materials selection particularly with lightweight aggregate for building components will be the first step of lightweight construction. In the next step, in addition to selecting the prominent samples of Iran's traditional architecture, the process of these works improvement is analyzed through the viewpoints of structural efficiency and lightweighting and also the practical methods of lightweight construction have been extracted. The optimum design of load bearing geometry of structural system has to be considered not only in the structural system elements, but also in their composition and the selection of dimensions, proportions, forms and optimum orientations, can lead to get a maximum materials efficiency for loads and stresses bearing.

Keywords: gravity load, light-weighting structural system, load bearing geometry, seismic behavior

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4613 Hybrid Control Strategy for Nine-Level Asymmetrical Cascaded H-Bridge Inverter

Authors: Bachir Belmadani, Rachid Taleb, M’hamed Helaimi

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Multilevel inverters are well used in high power electronic applications because of their ability to generate a very good quality of waveforms, reducing switching frequency, and their low voltage stress across the power devices. This paper presents the hybrid pulse-width modulation (HPWM) strategy of a uniform step asymmetrical cascaded H-bridge nine-level Inverter (USACHB9LI). The HPWM approach is compared to the well-known sinusoidal pulse-width modulation (SPWM) strategy. Simulation results demonstrate the better performances and technical advantages of the HPWM controller in feeding a high power induction motor.

Keywords: uniform step asymmetrical cascaded h-bridge high-level inverter, hybrid pwm, sinusoidal pwm, high power induction motor

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4612 Differences in the Processing of Sentences with Lexical Ambiguity and Structural Ambiguity: An Experimental Study

Authors: Mariana T. Teixeira, Joana P. Luz

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This paper is based on assumptions of psycholinguistics and investigates the processing of ambiguous sentences in Brazilian Portuguese. Specifically, it aims to verify if there is a difference in processing time between sentences with lexical ambiguity and sentences with structural (or syntactic) ambiguity. We hypothesize, based on the Garden Path Theory, that the two types of ambiguity entail different cognitive efforts, since sentences with structural ambiguity require that two structures be processed, whereas ambiguous phrases whose root of ambiguity is in a word require the processing of a single structure, which admits a variation of punctual meaning, within the scope of only one lexical item. In order to test this hypothesis, 25 undergraduate students, whose average age was 27.66 years, native speakers of Brazilian Portuguese, performed a self-monitoring reading task of ambiguous sentences, which had lexical and structural ambiguity. The results suggest that unambiguous sentence processing is faster than ambiguous sentence processing, whether it has lexical or structural ambiguity. In addition, participants presented a mean reading time greater for sentences with syntactic ambiguity than for sentences with lexical ambiguity, evidencing a greater cognitive effort in sentence processing with structural ambiguity.

Keywords: Brazilian portuguese, lexical ambiguity, sentence processing, syntactic ambiguity

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4611 Structural Analysis and Detail Design of APV Module Structure Using Topology Optimization Design

Authors: Hyun Kyu Cho, Jun Soo Kim, Young Hoon Lee, Sang Hoon Kang, Young Chul Park

Abstract:

In the study, structure for one of offshore drilling system APV(Air Pressure Vessle) modules was designed by using topology optimum design and performed structural safety evaluation according to DNV rules. 3D model created base on design area and non-design area separated by using topology optimization for the environmental loads. This model separated 17 types for wind loads and dynamic loads and performed structural analysis evaluation for each model. As a result, the maximum stress occurred 181.25MPa.

Keywords: APV, topology optimum design, DNV, structural analysis, stress

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4610 The MHz Frequency Range EM Induction Device Development and Experimental Study for Low Conductive Objects Detection

Authors: D. Kakulia, L. Shoshiashvili, G. Sapharishvili

Abstract:

The results of the study are related to the direction of plastic mine detection research using electromagnetic induction, the development of appropriate equipment, and the evaluation of expected results. Electromagnetic induction sensing is effectively used in the detection of metal objects in the soil and in the discrimination of unexploded ordnances. Metal objects interact well with a low-frequency alternating magnetic field. Their electromagnetic response can be detected at the low-frequency range even when they are placed in the ground. Detection of plastic things such as plastic mines by electromagnetic induction is associated with difficulties. The interaction of non-conducting bodies or low-conductive objects with a low-frequency alternating magnetic field is very weak. At the high-frequency range where already wave processes take place, the interaction increases. Interactions with other distant objects also increase. A complex interference picture is formed, and extraction of useful information also meets difficulties. Sensing by electromagnetic induction at the intermediate MHz frequency range is the subject of research. The concept of detecting plastic mines in this range can be based on the study of the electromagnetic response of non-conductive cavity in a low-conductivity environment or the detection of small metal components in plastic mines, taking into account constructive features. The detector node based on the amplitude and phase detector 'Analog Devices ad8302' has been developed for experimental studies. The node has two inputs. At one of the inputs, the node receives a sinusoidal signal from the generator, to which a transmitting coil is also connected. The receiver coil is attached to the second input of the node. The additional circuit provides an option to amplify the signal output from the receiver coil by 20 dB. The node has two outputs. The voltages obtained at the output reflect the ratio of the amplitudes and the phase difference of the input harmonic signals. Experimental measurements were performed in different positions of the transmitter and receiver coils at the frequency range 1-20 MHz. Arbitrary/Function Generator Tektronix AFG3052C and the eight-channel high-resolution oscilloscope PICOSCOPE 4824 were used in the experiments. Experimental measurements were also performed with a low-conductive test object. The results of the measurements and comparative analysis show the capabilities of the simple detector node and the prospects for its further development in this direction. The results of the experimental measurements are compared and analyzed with the results of appropriate computer modeling based on the method of auxiliary sources (MAS). The experimental measurements are driven using the MATLAB environment. Acknowledgment -This work was supported by Shota Rustaveli National Science Foundation (SRNSF) (Grant number: NFR 17_523).

Keywords: EM induction sensing, detector, plastic mines, remote sensing

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4609 Efficient Microspore Isolation Methods for High Yield Embryoids and Regeneration in Rice (Oryza sativa L.)

Authors: S. M. Shahinul Islam, Israt Ara, Narendra Tuteja, Sreeramanan Subramaniam

Abstract:

Through anther and microspore culture methods, complete homozygous plants can be produced within a year as compared to the long inbreeding method. Isolated microspore culture is one of the most important techniques for rapid development of haploid plants. The efficiency of this method is influenced by several factors such as cultural conditions, growth regulators, plant media, pretreatments, physical and growth conditions of the donor plants, pollen isolation procedure, etc. The main purpose of this study was to improve the isolated microspore culture protocol in order to increase the efficiency of embryoids, its regeneration and reducing albinisms. Under this study we have tested mainly three different microspore isolation procedures by glass rod, homozeniger and by blending and found the efficiency on gametic embryogenesis. There are three types of media viz. washing, pre-culture and induction was used. The induction medium as AMC (modified MS) supplemented by 2, 4-D (2.5 mg/l), kinetin (0.5 mg/l) and higher amount of D-Manitol (90 g/l) instead of sucrose and two types of amino acids (L-glutamine and L-serine) were used. Out of three main microspore isolation procedure by homogenizer isolation (P4) showed best performance on ELS induction (177%) and green plantlets (104%) compared with other techniques. For all cases albinisims occurred but microspore isolation from excised anthers by glass rod and homogenizer showed lesser numbers of albino plants that was also one of the important findings in this study.

Keywords: androgenesis, pretreatment, microspore culture, regeneration, albino plants, Oryza sativa

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4608 Hypothesis about the Origin of the Lighting

Authors: Igor Kuzminov

Abstract:

Till now, the nature of lightning is not established. A hypothesis of the origin of lightning is proposed. The lightning charge is formed by electromagnetic induction. The role of the conductor is performed by the air mass of the cloud. This conductor moves in the Earth's magnetic field. The upper and lower edges of the cloud are the plates of the capacitor. Lightning is a special case of electromagnetic processes in an atmosphere. The category of lightning occurs in the process of accumulation of a charge. The process of accumulation goes constantly, but the charge is not fixed. Naturally, the hypothesis demands the carrying out of additional experiments and official acknowledgement. As the proof of a hypothesis can serve that the maximal lighting activity in an equatorial zone where cosφ it is close to 1. An experiment conducted privately showed that there is a potential difference in the atmosphere at different levels. The probability of applied value development of power installation is great.

Keywords: electromagnetic induction, Earth's magnetic field, plates of the capacitors, charge accumulation

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4607 Reliability-Based Codified Design of Concrete Structures

Authors: Naser Alenezi, Ibrahim Alsakkaf, Osama Eid

Abstract:

The main objective of this study is to develop an independent reliability based code for reinforced concrete (R/C) structural components and elements solely for the State of Kuwait and its neighboring countries. The proposed code will take into account the harsh Kuwait’s harsh environment, loading conditions and material strengths. The method for developing such a code is based on structural reliability theory that takes into accounts the specific geographical and the various prescribed societal environment of the Kuwait region. These methods were developed according to the following four components: (1) loads, (2) structural strength, (3) reliability analysis, and (4) achieving target reliability levels (reliability index ’s ). The final product from this study will be a design code for R/C structural elements that include beams and columns, and some other structural members. This reliability-based LRFD design code will provide appropriate, easy, fast, and economical approach for designing R/C structural elements such as, beams and columns, for both houses and bridges, and other concrete structures. In addition, this reliability-based codified design of R/C beams, columns, and, possibly, concrete slabs will improve the design and serviceability of R/C bridge and building systems in Kuwait and neighboring GCC countries. Also, it has the potential to reduce the cost of new concrete structures, as fewer materials are used with more design efficiency.

Keywords: live laod, design, evaluation, structural building

Procedia PDF Downloads 310
4606 Concepts in the Design of Lateral-Load Systems in High Rise Buildings to Reduce Operational Energy Consumption

Authors: Mohamed Ali MiladKrem Salem, Sergio F.Breña, Sanjay R. Arwade, Simi T. Hoque

Abstract:

The location of the main lateral‐load resisting system in high-rise buildings may have positive impacts on sustainability through a reduction in operational energy consumption, and this paper describes an assessment of the accompanying effects on structural performance. It is found that there is a strong influence of design for environmental performance on the structural performance the building, and that systems selected primarily with an eye towards energy use reduction may require substantial additional structural stiffening to meet safety and serviceability limits under lateral load cases. We present a framework for incorporating the environmental costs of meeting structural design requirements through the embodied energy of the core structural materials and also address the issue of economic cost brought on by incorporation of environmental concerns into the selection of the structural system. We address these issues through four case study high-rise buildings with differing structural morphologies (floor plan and core arrangement) and assess each of these building models for cost and embodied energy when the base structural system, which has been suggested by architect Kenneth Yeang based on environmental concerns, is augmented to meet lateral drift requirements under the wind loads prescribed by ASCE 7-10.

Keywords: sustainable, embodied, Outrigger, skyscraper, morphology, efficiency

Procedia PDF Downloads 437