Search results for: finite group
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10443

Search results for: finite group

10173 Effect of Hill Interval Training on VO₂ Max among Filed Hockey Players

Authors: Sujay Bisht

Abstract:

The purpose of the study was to evaluate and find out the effect of Hill interval training on VO₂ MAX among field Hockey players. Thirty male field hockey players were selected from LNIPE, Guwahati who were studied in B.P.Ed course. The selected subjects were aged between 18 to 23 years. The VO₂ MAX was calculated and they were divided into two group. One group (N=15) considered as control group that did not participated in any special training apart from regular scheduled/curriculum and another group (N=15) considered as an experimental group which underwent four week Hill Training program. The selected criterion variable such VO₂ Max was measured by the cooper 12min/run/walk test and scores was recorded in ml/kg/min. The subjects were tested on selected criterion variable such as VO₂ Max prior and immediately after the training program. The pretest and posttest data were evaluate by the Analysis of Covariance (ANCOVA) to find out the significance difference if any between the experimental and control group on selected criterion variable. The level of significance was set at 0.05 level of confidence. After applied ANCOVA it was revealed that there was a significant different among the experimental and control group on VO₂ Max. Finally it was concluded that 4 week of Hill interval training effect the VO₂ max performance of field hockey players.

Keywords: VO₂ max, hill interval training, ANCOVA, experimental group

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10172 Anterior Segment Optical Coherence Tomography Study of Cornea and Tear Film Parameters in Juvenile Systemic Lupus Erythematous Patients

Authors: Mohamed Salah El-Din Mahmoud, Ahmed Hamed, Asmaa Anwar Mohamed

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Purpose: To study the tear film parameters, total corneal thickness (CT), corneal epithelial thickness and, corneal power in Juvenile systemic lupus erythematosus (JSLE) patients compared to age-matched controls using anterior segment optical coherence tomography (AS-OCT). Methods: This was a cross-sectional study. Study participants were divided into 2 groups: Group A: 75 eyes of JSLE patients, Group B: 75 eyes of healthy controls. Tear meniscus height (TMH), tear meniscus depth (TMD), and tear meniscus area (TMA) were the lower tear meniscus parameters that were measured. The corneal power, CT, and epithelial thickness were all determined automatically. Results: In the JSLE group, the range of age was 10 to 15 years while the control group was 11 to 16 years. TMH, TMA, and TMD were 527.7±46.8, 0.059±0.015 and 343.3±59.9 respectively in JSLE group while 525.4±44.6, 0.058±0.011 and 340.6±58.0 respectively in control group without significant difference (p-value<0.001). The corneal power was 43.3±0.55 in the JSLE while 43.2±0.54 in the control group without significant difference (p-value= 0.407). CT was 551.1±13.5 in JSLE group while 551.2±15.3 in control group without significant difference (p-value= 0.982). Epithelial thickness was 52.66±1.35 in the JSLE group while 52.60±1.36 in the control group without significant difference (p-value= 0.765). Conclusion: We demonstrated no significant difference in tear meniscus dimensions, CT, epithelial thickness, and corneal power in the JSLE patients compared to age-matched controls using AS-OCT.

Keywords: tear film, ASOCT, JSLE, pachymetry, corneal thickness

Procedia PDF Downloads 164
10171 Structural Evaluation of Airfield Pavement Using Finite Element Analysis Based Methodology

Authors: Richard Ji

Abstract:

Nondestructive deflection testing has been accepted widely as a cost-effective tool for evaluating the structural condition of airfield pavements. Backcalculation of pavement layer moduli can be used to characterize the pavement existing condition in order to compute the load bearing capacity of pavement. This paper presents an improved best-fit backcalculation methodology based on deflection predictions obtained using finite element method (FEM). The best-fit approach is based on minimizing the squared error between falling weight deflectometer (FWD) measured deflections and FEM predicted deflections. Then, concrete elastic modulus and modulus of subgrade reaction were back-calculated using Heavy Weight Deflectometer (HWD) deflections collected at the National Airport Pavement Testing Facility (NAPTF) test site. It is an alternative and more versatile method in considering concrete slab geometry and HWD testing locations compared to methods currently available.

Keywords: nondestructive testing, pavement moduli backcalculation, finite element method, concrete pavements

Procedia PDF Downloads 162
10170 The Permutation of Symmetric Triangular Equilateral Group in the Cryptography of Private and Public Key

Authors: Fola John Adeyeye

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In this paper, we propose a cryptosystem private and public key base on symmetric group Pn and validates its theoretical formulation. This proposed system benefits from the algebraic properties of Pn such as noncommutative high logical, computational speed and high flexibility in selecting key which makes the discrete permutation multiplier logic (DPML) resist to attack by any algorithm such as Pohlig-Hellman. One of the advantages of this scheme is that it explore all the possible triangular symmetries. Against these properties, the only disadvantage is that the law of permutation multiplicity only allow an operation from left to right. Many other cryptosystems can be transformed into their symmetric group.

Keywords: cryptosystem, private and public key, DPML, symmetric group Pn

Procedia PDF Downloads 198
10169 Developing a Group Guidance Framework: A Review of Literature

Authors: Abdul Rawuf Hussein, Rusnani Abdul Kadir, Mona Adlina Binti Adanan

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Guidance program has been an essential approach in helping professions from many institutions of learning as well as communities, organizations, and clinical settings. Although the term varies depending on the approaches, objectives, and theories, the core and central element is typically developmental in nature. In this conceptual paper, the researcher will review literature on the concept of group guidance, its impact on students’ and individual’s development, developing a guidance module and proposing a synthesised framework for group guidance program.

Keywords: concept, framework, group guidance, module development

Procedia PDF Downloads 516
10168 Estimation of a Finite Population Mean under Random Non Response Using Improved Nadaraya and Watson Kernel Weights

Authors: Nelson Bii, Christopher Ouma, John Odhiambo

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Non-response is a potential source of errors in sample surveys. It introduces bias and large variance in the estimation of finite population parameters. Regression models have been recognized as one of the techniques of reducing bias and variance due to random non-response using auxiliary data. In this study, it is assumed that random non-response occurs in the survey variable in the second stage of cluster sampling, assuming full auxiliary information is available throughout. Auxiliary information is used at the estimation stage via a regression model to address the problem of random non-response. In particular, the auxiliary information is used via an improved Nadaraya-Watson kernel regression technique to compensate for random non-response. The asymptotic bias and mean squared error of the estimator proposed are derived. Besides, a simulation study conducted indicates that the proposed estimator has smaller values of the bias and smaller mean squared error values compared to existing estimators of finite population mean. The proposed estimator is also shown to have tighter confidence interval lengths at a 95% coverage rate. The results obtained in this study are useful, for instance, in choosing efficient estimators of the finite population mean in demographic sample surveys.

Keywords: mean squared error, random non-response, two-stage cluster sampling, confidence interval lengths

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10167 A Comparative Study of Granisetron and Palonosetron in Postoperative Nausea and Vomiting Following Laparoscopic Surgery

Authors: Burra Vijitha

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A prospective randomized comparative study for the prevention of postoperative nausea and vomiting in the patients undergoing general anesthesia ,for elective laparoscopic surgeries with respect to efficacy and side effects of granisetron and palonosetron. Sixty adult patients of class ASA 1,2 of either sex in age group between 20-70 yrs,scheduled for elective laparoscopic surgeries were selected for the study.Patients were randomly divided into two groups 30 each. Group G: Granisetron group (n=30), 40µg/kg; Group P: Palonosetron group (n=30), 0.075 mg. at end of surgery before extubation group G patients 40 µg/kg of inj.granisetron and group P patients received 0.075 mg of inj.palonosetron slow iv over 30 sec.In post anesthesia care unit, episodes of nausea and vomiting experienced by each patient was recorded by direct questioning the patient .study medication was assessed in terms of incidence of nausea and vomiting during periods of 0-4 hrs,4-12 hrs,12-24 hrs,24-48hrs.our study demonstrated that complete response for those patients who received granisetron were 86.66%,80% and 66.66% ,while those received palonosetron were 100%,86.6%,90% between 0-4hrs,4-12hrs,12-24 hrs. It shows no statistically signidficant differences between the baseline values of hemodynamic variables beween two groups during study. Keywords: Granisetron, nausea, palonosetron, vomiting.

Keywords: granisetron, palonosetron, nausea, vomiting

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10166 Efficacy and Safety of Inhaled Nebulized Chemotherapy in Treatment of Patients with Newly Diagnosed Pulmonary Tuberculosis in Comparison to Standard Antimycobacterial Therapy

Authors: M. Kuzhko, M. Gumeniuk, D. Butov, T. Tlustova, O. Denysov, T. Sprynsian

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Abstract: The objective of this work was to study the efficacy and safety of inhaled nebulized chemotherapy in the treatment of patients with newly diagnosed pulmonary tuberculosis in comparison with standard antimycobacterial therapy. Materials and methods: The study involved 68 patients aged between 20 and 70 years with newly diagnosed pulmonary tuberculosis. Patients were allocated to two groups. The first (main, n=21) group of patients received standard chemotherapy and further 0.15 g of isoniazid and rifampicin 0.15 g inhaled through a nebulizer, also they received salmeterol 50 mcg + fluticasone propionate 250 mcg at 2 breaths twice a day for 2 months. The second (control, n=47) group of patients received standard chemotherapy, consisting of orally administered isoniazid (0.3 g), rifampicin (0.6 g), pyrazinamide (2 g), ethambutol (1.2 g) with a dose reduction after the intensive phase of the therapy. The anti-TB drugs were procured through the Ukraine’s centralized national supply system. Results: Intoxication symptoms in the first group reduced following 1.39±0.18 months, whereas in the second group, intoxication symptoms reduced following 2.7±0.1 months, p<.001. Moreover, respiratory symptoms regression in the first group was observed following 1.6±0.2 months, whereas in the second group – following 2.5±0.2 months, p<0.05. Bacillary excretion period evaluated within 1 month was reduced, as it was shown by 66.6±10.5% in the main group compared to 27.6±6.5%, p<0.05, in the control group. In addition, period of cavities healing was reduced to 2.9±0.2 months in the main group compared to 3.7±0.1 months, p<0.05, in the control group. Residual radiological lung damage findings (large residual changes) were observed in 22 (23.8±9.5 %) patients of the main group versus 24 (51.0±7.2 %) patients in the control group, p<0.05. After completion of treatment scar stenosis of the bronchi II-III art. diagnosed in 3 (14.2±7.8%) patients in main group and 17 (68.0±6.8%) - control group, p<0.05. The duration of hospital treatment was 2.4±0.4 months in main group and 4.1±0.4 months in control group, p<0.05. Conclusion: Administration of of inhaled nebulized chemotherapy in patients with newly diagnosed pulmonary tuberculosis resulted in a comparatively quick reduction of disease manifestation.

Keywords: inhaled nebulized chemotherapy, pulmonary tuberculosis, tuberculosis, treatment of tuberculosis

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10165 Influence of Existing Foundations on Soil-Structure Interaction of New Foundations in a Reconstruction Project

Authors: Kanagarajah Ravishankar

Abstract:

This paper describes a study performed for a project featuring an elevated steel bridge structure supported by various types of foundation systems. This project focused on rehabilitation or redesign of a portion of the bridge substructures founded on caisson foundations. The study that this paper focuses on is the evaluation of foundation and soil stiffnesses and interactions between the existing caissons and proposed foundations. The caisson foundations were founded on top of rock, where the depth to the top of rock varies from approximately 50 to 140 feet below ground surface. Based on a comprehensive investigation of the existing piers and caissons, the presence of ASR was suspected from observed whitish deposits on cracked surfaces as well as internal damages sustained through the entire depth of foundation structures. Reuse of existing piers and caissons was precluded and deemed unsuitable under the earthquake condition because of these defects on the structures. The proposed design of new foundations and substructures which was selected ultimately neglected the contribution from the existing caisson and pier columns. Due to the complicated configuration between the existing caisson and the proposed foundation system, three-dimensional finite element method (FEM) was employed to evaluate soil-structure interaction (SSI), to evaluate the effect of the existing caissons on the proposed foundations, and to compare the results with conventional group analysis. The FEM models include separate models for existing caissons, proposed foundations, and combining both.

Keywords: soil-structure interaction, foundation stiffness, finite element, seismic design

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10164 3D Finite Element Analysis for Mechanics of Soil-Tool Interaction

Authors: A. Armin, R. Fotouhi, W. Szyszkowski

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This paper is part of a study to develop robots for farming. As such power requirement to operate equipment attach to such robots become an important factor. Soil-tool interaction play major role in power consumption, thus predicting accurately the forces which act on the blade during the farming is prime importance for optimal designing of farm equipment. In this paper a finite element investigation for tillage tools and soil interaction is described by using an inelastic constitutive material law for agriculture application. A 3-dimentional (3D) nonlinear finite element analysis (FEA) is developed to examine behavior of a blade with different rake angles moving in a block of soil, and to estimate the blade force. The soil model considered is an elastic-plastic with non-associated Drucker-Prager material model. Special use of contact elements are employed to consider connection between soil-blade and soil-soil surfaces. The FEA results are compared with experiment ones, which show good agreement in accurately predicting draft forces developed on the blade when it moves through the soil. Also, a very good correlation was obtained between FEA results and analytical results from classical soil mechanics theories for straight blades. These comparisons verified the FEA model developed. For analyzing complicated soil-tool interactions and for optimum design of blades, this method will be useful.

Keywords: finite element analysis, soil-blade contact modeling, blade force, mechanical engineering

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10163 To Individualisation of Subject, Donar, by Determination of Serological Markers from Obtain Biological Fluid at Crime Scene

Authors: Arun Kumar, Ravindra Pal Verma, Harsh Sharma, Shani Kumar

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For the present study samples was collected from 20 donors with unknown blood group and secretor status had been determined from saliva by using biological fluid. ABO typing on the concentrated samples was successfully performed after 1 month of storage. Urine stained clothing samples are often submitted to forensic science laboratories for ABH blood group antigen determination. The serogenetic markers of semen stains submitted can be used to determine the origin of any of these samples. ABH blood group substances have previously been identified from urine. ABH blood group substance is low in urine in comparison with other body fluids.

Keywords: ABH blood group, crime scene, serological markers, body fluids and urine

Procedia PDF Downloads 579
10162 The Effectiveness of Group Spiritual Therapy on Increasing the Life Expectancy and Mental Health in Elderlies

Authors: Seyed Reza Mirmahdi, Seyedeh Maryam Hashemi Jabali

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This research was conducted to evaluate the effects of group spiritual therapy on increasing the life expectancy and mental health among the elderlies. This was a quasi-experimental research using a pretest-posttest design with a control group conducted over a population including all the elderly people of Tehran in 2012-13. A randomized sampling method was used to select 30 elderly people living in Parham nursing home that were then randomly assigned into two control and experimental groups of 15 people each. The instruments used were Miller’s life expectancy and mental health test (SCL.90.R) standard questionnaires. Individuals in experimental group received 12 sessions of group spiritual therapy while those in control group did not receive any kind of therapy. The tests were performed again for all the subjects (30 individuals) at the end of the experiment. To test the hypotheses, the data collected by questionnaires were analyzed using descriptive methods through relevant tables and charts and also inferential methods through the analysis of covariance using the SPSS software. Results showed that group spiritual therapy leads to a significant increase in both mental health and life expectancy in the experimental group of elderlies living in Parham nursing home compared to those in the control group.

Keywords: spiritual therapy, life expectancy, mental health, elderlies

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10161 Identification of High Stress Regions in Proximal Femur During Single-Leg Stance and Sideways Fall Using QCT-Based Finite Element Model

Authors: Hossein Kheirollahi, Yunhua Luo

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Studying stress and strain trends in the femur and recognizing femur failure mechanism is very important for preventing hip fracture in the elderly. The aim of this study was to identify high stress and strain regions in the femur during normal walking and falling to find the mechanical behavior and failure mechanism of the femur. We developed a finite element model of the femur from the subject’s quantitative computed tomography (QCT) image and used it to identify potentially high stress and strain regions during the single-leg stance and the sideways fall. It was found that fracture may initiate from the superior region of femoral neck and propagate to the inferior region during a high impact force such as sideways fall. The results of this study showed that the femur bone is more sensitive to strain than stress which indicates the effect of strain, in addition to effect of stress, should be considered for failure analysis.

Keywords: finite element analysis, hip fracture, strain, stress

Procedia PDF Downloads 500
10160 Hybrid Finite Element Analysis of Expansion Joints for Piping Systems in Aircraft Engine External Configurations and Nuclear Power Plants

Authors: Dong Wook Lee

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This paper presents a method to analyze the stiffness of the expansion joint with structural support using a hybrid method combining computational and analytical methods. Many expansion joints found in tubes and ducts of mechanical structures are designed to absorb thermal expansion mismatch between their structural members and deal with misalignments introduced from the assembly/manufacturing processes. One of the important design perspectives is the system’s vibrational characteristics. We calculate the stiffness as a characterization parameter for structural joint systems using a combined Finite Element Analysis (FEA) and an analytical method. We apply the methods to two sample applications: external configurations of aircraft engines and nuclear power plant structures.

Keywords: expansion joint, expansion joint stiffness, finite element analysis, nuclear power plants, aircraft engine external configurations

Procedia PDF Downloads 105
10159 Effects of Visual Agnosia in Children’s Linguistic Abilities: Psychoneurolinguistic Approach

Authors: Sadeq Al Yaari, Ayman Al Yaari, Adham Al Yaari, Montaha Al Yaari, Aayah Al Yaari, Sajedah Al Yaari

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Objective: The aim of the study is to examine the relationship between visual agnosia and learning delay in Yemeni children. Method: A total of 80 subjects (experimental group= 60, 30 males and 30 females and control group= 20, 10 males and 10 females) in two institutions (old and new). The age of all subjects at hand ranges between 6- and 12 years old. Pre and post-tests were administered. Results: Outline results show severe effects on the performance of the children due to visual agnosia this effect was benign in the group that received the treatment, and this can be clearly seen in their results in the post-test compared to the other group that did not receive the treatment and outcomes in general can be better understood in light of the control group.

Keywords: visual, agnosia, linguistics, abilities, effects, psychoneurolinguistics

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10158 On the Volume of Ganglion Cell Stimulation in Visual Prostheses by Finite Element Discretization

Authors: Diego Luján Villarreal

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Visual prostheses are designed to repair some eyesight in patients blinded by photoreceptor diseases, such as retinitis pigmentosa (RP) and age-related macular degeneration (AMD). Electrode-to-cell proximity has drawn attention due to its implications on secure single-localized stimulation. Yet, few techniques are available for understanding the relationship between the number of cells activated and the current injection. We propose an answering technique by solving the governing equation for time-dependent electrical currents using finite element discretization to obtain the volume of stimulation.

Keywords: visual prosthetic devices, volume for stimulation, FEM discretization, 3D simulation

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10157 A Coupled Extended-Finite-Discrete Element Method: On the Different Contact Schemes between Continua and Discontinua

Authors: Shervin Khazaeli, Shahab Haj-zamani

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Recently, advanced geotechnical engineering problems related to soil movement, particle loss, and modeling of local failure (i.e. discontinua) as well as modeling the in-contact structures (i.e. continua) are of the great interest among researchers. The aim of this research is to meet the requirements with respect to the modeling of the above-mentioned two different domains simultaneously. To this end, a coupled numerical method is introduced based on Discrete Element Method (DEM) and eXtended-Finite Element Method (X-FEM). In the coupled procedure, DEM is employed to capture the interactions and relative movements of soil particles as discontinua, while X-FEM is utilized to model in-contact structures as continua, which may consist of different types of discontinuities. For verification purposes, the new coupled approach is utilized to examine benchmark problems including different contacts between/within continua and discontinua. Results are validated by comparison with those of existing analytical and numerical solutions. This study proves that extended-finite-discrete element method can be used to robustly analyze not only contact problems, but also other types of discontinuities in continua such as (i) crack formations and propagations, (ii) voids and bimaterial interfaces, and (iii) combination of previous cases. In essence, the proposed method can be used vastly in advanced soil-structure interaction problems to investigate the micro and macro behaviour of the surrounding soil and the response of the embedded structure that contains discontinuities.

Keywords: contact problems, discrete element method, extended-finite element method, soil-structure interaction

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10156 Variation of Hedonic Capacity of People According to Age and Its Correlation with Chronotype

Authors: T. Hojageldiyev, Y. Bolmammedov

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Increasing evidence suggests late chronotype individuals are at increased risk of developing psychopathological conditions. Our previously conducted study aimed to know the distribution of chronotypes according to age revealed that evening-types reaching a peak at age 14. While there is growing number of studies evaluating associations between chronotype and affective symptoms, to our best knowledge there are no studies addressing the issue of prevalence of anhedonia according to age groups of people. The sample included 545 healthy students between 13-21 years old from secondary schools and universities of Turkmenistan. Self-report 14 item Snaith-Hamilton Pleasure Scale (SHAPS) was used to assess hedonic tone of students. SHAPS score of 3 or higher indicates the criteria for the anhedonia. According to similarity of hedonic capacity participants divided into three age groups. Group I (age 13-14-15) includes 206 students (92 female), group II (age 16-17) includes 256 students (111 female) and group III (age 18-19-20-21) includes 83 (37 female). Statistical analysis was performed using Microsoft Excel 2013 and GraphPad Prism 7.0 programs. According to results average SHAPS scores of group I is 1.93 ± 1.94, group II 1.08 ± 1.43 and group III 1.29 ± 1.62. Students with anhedonia in group I consisted 30.5%, in group II 13,2% and in group III 12.04%. There are no gender differences. According to questionnaire results, higher prevalence of anhedonia is at the age between 13-15 than other age groups, and hedonic capacity increases as the age of students increases (p < 0.05). As a result, distribution of evening-types according to age correlates with hedonic capacity which is evening-types tends to have lower hedonic capacity.

Keywords: anhedonia, age, chronotype, hedonic capacity

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10155 Modelling Asymmetric Magnetic Recording Heads with an Underlayer Using Superposition

Authors: Ammar Edress Mohamed, Mustafa Aziz, David Wright

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This paper analyses and calculates the head fields of asymmetrical 2D magnetic recording heads when the soft-underlayer is present using the appropriate Green's function to derive the surface potential/field by utilising the surface potential for asymmetrical head without underlayer. The results follow closely the corners, while the gap region shows a linear behaviour for d/g < 0.5 compared with the calculated fields from finite-element.

Keywords: magnetic recording, finite elements, asymmetrical magnetic heads, superposition, Laplace's equation

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10154 Multi-Disciplinary Optimisation Methodology for Aircraft Load Prediction

Authors: Sudhir Kumar Tiwari

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The paper demonstrates a methodology that can be used at an early design stage of any conventional aircraft. This research activity assesses the feasibility derivation of methodology for aircraft loads estimation during the various phases of design for a transport category aircraft by utilizing potential of using commercial finite element analysis software, which may drive significant time saving. Early Design phase have limited data and quick changing configuration results in handling of large number of load cases. It is useful to idealize the aircraft as a connection of beams, which can be very accurately modelled using finite element analysis (beam elements). This research explores the correct approach towards idealizing an aircraft using beam elements. FEM Techniques like inertia relief were studied for implementation during course of work. The correct boundary condition technique envisaged for generation of shear force, bending moment and torque diagrams for the aircraft. The possible applications of this approach are the aircraft design process, which have been investigated.

Keywords: multi-disciplinary optimization, aircraft load, finite element analysis, stick model

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10153 Mathematical and Numerical Analysis of a Nonlinear Cross Diffusion System

Authors: Hassan Al Salman

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We consider a nonlinear parabolic cross diffusion model arising in applied mathematics. A fully practical piecewise linear finite element approximation of the model is studied. By using entropy-type inequalities and compactness arguments, existence of a global weak solution is proved. Providing further regularity of the solution of the model, some uniqueness results and error estimates are established. Finally, some numerical experiments are performed.

Keywords: cross diffusion model, entropy-type inequality, finite element approximation, numerical analysis

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10152 Investigation of the Multiaxial Pedicle Screw Tulip Design Using Finite Element Analysis

Authors: S. Daqiqeh Rezaei, S. Mohajerzadeh, M. R. Sharifi

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Pedicle screws are used to stabilize vertebrae and treat several types of spinal diseases and injuries. Multiaxial pedicle screws are a type of pedicle screw that increase surgical versatility, but they also increase design complexity. Failure of multiaxial pedicle screws caused by static loading, dynamic loading and fatigue can lead to irreparable damage to the patient. Inappropriate deformation of the multiaxial pedicle screw tulip can cause system failure. Investigation of deformation and stress in these tulips can be employed to optimize multiaxial pedicle screw design. The sensitivity of this matter necessitates precise analyzing and modeling of pedicle screws. In this work, three commercial multiaxial pedicle screw tulips and a newly designed tulip are investigated using finite element analysis. Employing video measuring machine (VMM), tulips are modeled. Afterwards, utilizing ANSYS, static analysis is performed on these models. In the end, stresses and displacements of the models are compared.

Keywords: pedicle screw, multiaxial pedicle screw, finite element analysis, static analysis

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10151 Is There a Group of "Digital Natives" at Secondary Schools?

Authors: L. Janská, J. Kubrický

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The article describes a research focused on the influence of the information and communication technology (ICT) on the pupils' learning. The investigation deals with the influences that distinguish between the group of pupils influenced by ICT and the group of pupils not influenced by ICT. The group influenced by ICT should evince a different approach in number of areas (in managing of two and more activities at once, in a quick orientation and searching for information on the Internet, in an ability to quickly and effectively assess the data sources, in the assessment of attitudes and opinions of the other users of the network, in critical thinking, in the preference to work in teams, in the sharing of information and personal data via the virtual social networking, in insisting on the immediate reaction on their every action etc.).

Keywords: ICT influence, digital natives, pupil´s learning

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10150 Experimental Investigations on Group Interaction Effects of Laterally Loaded Piles in Submerged Sand

Authors: Jasaswini Mishra, Ashim K. Dey

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This paper aims to investigate the group interaction effects of laterally loaded pile groups driven into a medium dense sand layer in submerged state. Static lateral load tests were carried out on pile groups consisting of varying number of piles and at different spacings. The test setup consists of a load cell (500 kg capacity) and an LVDT (50 mm) to measure the load and pile head deflection respectively. The piles were extensively instrumented with strain gauges so as to study the variation of soil resistance within the group. The bending moments at various depths were calculated from strain gauge data and these curves were fitted using a higher order polynomial in order to get 'p-y' curves. A comparative study between a single pile and a pile under a group has also been done for a better understanding of the group effect. It is observed that average load per pile is significantly reduced relative to single pile and it decreases with increase in the number of piles in a pile group. The loss of efficiency of the piles in the group, commonly referred to as "shadowing" effect, has been expressed by the use of a 'p-multiplier'. Leading rows carries greater amount of load when compared with the trailing rows. The variations of bending moment with depth for different rows of pile within a group and different spacing have been analyzed and compared with that of a single pile. p multipliers within different rows in a pile group were evaluated from the experimental study.

Keywords: group action, laterally loaded piles, p-multiplier, strain gauge

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10149 Effect of Rituximab Therapy Depending on the Age of Disease Onset in Systemic Sclerosis

Authors: Liudmila Garzanova, Lidia Ananyeva, Olga Koneva, Olga Ovsyannikova, Oxana Desinova, Mayya Starovoytova, Rushana Shayahmetova, Anna Khelkovskaya-Sergeeva

Abstract:

Objectives. The age of the disease onset could have an impact on the effect of therapy in systemic sclerosis(SSc). Late-age onset in SSc could have a more severe course of the disease and worse clinical effects on therapy. The aim of our study was to evaluate changes in skin fibrosis on rituximab(RTX) therapy in patients with SSc and different ages of the disease onset. Methods. 151 patients with SSc were included in this study. Patients were divided into groups depending on the age of the disease onset: group 1 - younger than 30 years (40 patients(26%), group 2 - 31-59 years (90 patients(60%) and group 3 – more than 60 years (21 patients(14%). The mean follow-up period was 13±2.3month. The mean age was 48±13years, female-83% of patients, and the diffuse cutaneous subset of the disease had 52% of patients. The mean disease duration was 6.4±5years. The cumulative mean dose of RTX was 1.5±0.6grams. Patients received RTX as a therapy for interstitial lung disease. All patients received prednisone at a dose of 11.6±4.8mg/day, immunosuppressants received 48% of them. The results at baseline and at the end of the follow-up are presented in the form of mean values. Results. There was a significant decrease of modified Rodnan skin score(mRss) in all groups: in group 1 - from 10.2±8 to 7.7±6.5(p=0.01); in group 2 - from 9±7.2 to 6.2±4.7(p=0.0001); in group 3 - from 20.5±14.1 to 10.8±9.4(p=0.001). There was a significant decrease of the activity index (EScSG-AI): in group 1 from 2.5±1.8 to 1.3±1.1; in group 2 – from 3.2±1.6 to 1.5±1.2; in group 3 – from 4.2±2.1 to 1.3±1. Conclusion. There was a significant improvement in skin fibrosis in a year after initiation of RTX therapy regardless of the age of the disease onset. The improvement was more pronounced in the group with late-age onset of the disease, but these data require further investigations.

Keywords: skin fibrosis, systemic sclerosis, rituximab, disease onset

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10148 Effect of Preoperative Single Dose Dexamethasone and Lignocaine on Post-Operative Quality of Recovery and Pain Relief after Laparoscopic Cholecystectomy

Authors: Gurjeet Khurana, Surender Singh, Poonam Arora, Praveendra K. Sachan

Abstract:

Introduction: Post-operative quality of recovery is the key outcome in the perspective of anesthesiologist. It is directly related to patient satisfaction. This is unsurprising, considering most aspects of a poor quality recovery after surgery will impair satisfaction with care. This study was thus undertaken to evaluate effects of Dexamethasone and Lignocaine on Quality of Recovery using QoR- 40 questionnaire and compare their effects. Material and methods: After obtaining the ethical committee approval and written informed consent, 67 patients of 18-60 years, ASA grade I and II scheduled for elective laparoscopic cholecystectomy were randomly allocated into two groups. Group I of 34 patients received 2mg/kg lignocaine diluted to 10ml with normal saline. Group 2 of 33 patients received 0.1 mg/kg I/V Dexamethasone diluted to 10ml with normal saline. QoR-40 was assessed on pre-operative day, and again QoR-40 was assessed at 24 hr post-operative day-1. Postoperative pain scores, nausea and vomiting and shoulder pain were secondary outcomes. Results: The Global QoR-40 was more than 180 at 24 hr in both the groups. The Dexamethasone group had higher Global QoR-40 than lignocaine group 187.94 v/s 182.85. Amongst dimensions of QoR-40 Dexamethasone had statistically better physical comfort, physical independence, and pain relief as compared to Lignocaine. Positive items had excellent responses in Dexamethasone group. Headache, backache and sore throat were also less severe in Dexamethasone group as compared to Lignocaine group. Dexamethasone group had lower VAS compared to lignocaine group. Similarly, there was less fentanyl consumption in dexamethasone group (364.08 ± 127.31) in postoperative period when compared to the lignocaine group (412.31 ± 147.8). Group receiving dexamethasone had 36% increase in appetite compared to lignocaine group (17.6%), which facilitated early oral feeding. Frequency of PONV was less in group-2 at different time interval as compared to group 1. Total episode of PONV were 18 in group 1 and 7 in group 2. Statistically significant difference was seen among two groups (p value= 0.007). Use of antiemetic was more in group 1 as compared to group 2 at all the times, though it was not statistically significant at different time intervals. Antiemetics were administered to 18 patients in group 1 as compared to 5 patients in group 2 postoperatively. Statistically significant difference (p value= 0.011) was seen in total antiemetic consumption. Conclusion: Our study demonstrated that pre-operative administration of a single dose of dexamethasone enhanced the quality of recovery after laparoscopic cholecystectomy as compared to Lignocaine bolus dose.

Keywords: dexamethasone, lignocaine, QoR-40 questionnaire, quality of recovery

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10147 Effect of Erythropoietin Hormone Supplementation on Hypoxia-Inducible Factor1-Alpha in Rat Kidneys with Experimental Diabetic Nephropathy

Authors: Maha Deif, Alaa Eldin Hassan, Eman Shaat, Nesrine Elazhary, Eman Magdy

Abstract:

Background: Erythropoietin (EPO) is a hematopoietic factor with multiple protective effects. The aim of the present study was to investigate the potential effect of EPO administration on renal functions and hypoxia inducible factor 1-alpha (HIF-1a) in diabetic rat kidneys. Methodology: The current study was carried out on 40 male albino rats divided into four groups (n= 10 in each). Group I served as normal control, group II was the diabetic control, group III rats received EPO on the same day of diagnosis of diabetes mellitus (DM), while group IV received the first dose of EPO 2 weeks after the diagnosis of DM. Results: The results showed that EPO supplementation leads to a significant decrease in serum urea, urinary protein and creatinine clearance as well as a significant increase in renal HIF-1a in group III and IV rats compared to the diabetic control group (group II). However, fasting blood glucose was significantly decreased in group III as compared to the diabetic control group in the third week, but no significant difference was reported in the fourth week among groups II, III and IV. Conclusion: EPO administration leads to the improvement of renal functions and increased levels of HIF-1a in diabetic rats.

Keywords: erythropoietin, diabetic nephropathy, hypoxia-inducible factor1-alpha, renal functions

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10146 Second Representation of Modules over Commutative Rings

Authors: Jawad Abuhlail, Hamza Hroub

Abstract:

Let R be a commutative ring. Representation theory studies the representation of R-modules as (possibly finite) sums of special types of R-submodules. Here we are interested in a class of R-modules between the class of semisimple R-modules and the class of R-modules that can be written as (possibly finite) sums of secondary R-submodules (we know that every simple R-submodule is secondary). We investigate R-modules which can be written as (possibly finite) sums of second R-submodules (we call those modules second representable). Moreover, we investigate the class of (main) second attached prime ideals related to a module with such representation. We provide sufficient conditions for an R-module M to get a (minimal) second representation. We also found the collection of second attached prime ideals for some types of second representable R-modules, in particular within the class of injective R-modules. As we know that every simple R-submodule is second and every second R-submodule is secondary, we can see the importance of the second representable R-module.

Keywords: lifting modules, second attached prime ideals, second representations, secondary representations, semisimple modules, second submodules

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10145 The Effect of Arbitrary Support Conditions on the Static Behavior of Curved Beams Using the Finite Element Method

Authors: Hossein Mottaghi T., Amir R. Masoodi

Abstract:

This study presents a finite curved element for analyzing the static behavior of curved beams within the elastic range. The objective is to enhance accuracy while reducing the number of elements by incorporating first-order shear deformations of Timoshenko beams. Initially, finite element formulations are developed by considering polynomial initial functions for axial, shear, and rotational deformations for a three-node element. Subsequently, nodal interpolation functions for this element are derived, followed by the construction of the element stiffness matrix. To enable the utilization of the stiffness matrix in the static analysis of curved beams, the constructed matrix in the local coordinates of the element is transformed to the global coordinate system using the rotation matrix. A numerical benchmark example is investigated to assess the accuracy and effectiveness of this method. Moreover, the influence of spring stiffness on the rotation of the endpoint of a clamped beam is examined by substituting each support reaction of the beam with a spring. In the parametric study, the effect of the central angle of the beam on the rotation of the beam's endpoint in a cantilever beam under a concentrated load is examined. This research encompasses various mechanical, geometrical, and boundary configurations to evaluate the static characteristics of curved beams, thus providing valuable insights for their analysis and examination.

Keywords: curved beam, finite element method, first-order shear deformation theory, elastic support

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10144 A Study on the Failure Modes of Steel Moment Frame in Post-Earthquake Fire Using Coupled Mechanical-Thermal Analysis

Authors: Ehsan Asgari, Meisam Afazeli, Nezhla Attarchian

Abstract:

Post-earthquake fire is considered as a major threat in seismic areas. After an earthquake, fire is possible in structures. In this research, the effect of post-earthquake fire on steel moment frames with and without fireproofing coating is investigated. For this purpose, finite element method is employed. For the verification of finite element results, the results of an experimental study carried out by previous researchers are used, and the predicted FE results are compared with the test results, and good agreement is observed. After ensuring the accuracy of the predictions of finite element models, the effect of post-earthquake fire on the frames is investigated taking into account the parameters including the presence or absence of fire protection, frame design assumptions, earthquake type and different fire scenario. Ordinary fire and post-earthquake fire effect on the frames is also studied. The plastic hinges induced by earthquake in the structure are determined in the beam to the column connection and in panel zone. These areas should be accurately considered when providing fireproofing coatings. The results of the study show that the occurrence of fire beside corner columns is the most damaging scenario that results in progressive collapse of structure. It was also concluded that the behavior of structure in fire after a strong ground motion is significantly different from that in a normal fire.

Keywords: post earthquake fire, moment frame, finite element simulation, coupled temperature-displacement analysis, fire scenario

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