Search results for: Comparisons
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 231

Search results for: Comparisons

201 Application of Higher Order Splines for Boundary Value Problems

Authors: Pankaj Kumar Srivastava

Abstract:

Bringing forth a survey on recent higher order spline techniques for solving boundary value problems in ordinary differential equations. Here we have discussed the summary of the articles since 2000 till date based on higher order splines like Septic, Octic, Nonic, Tenth, Eleventh, Twelfth and Thirteenth Degree splines. Comparisons of methods with own critical comments as remarks have been included.

Keywords: Septic spline, Octic spline, Nonic spline, Tenth, Eleventh, Twelfth and Thirteenth Degree spline, parametric and non-parametric splines, thermal instability, astrophysics.

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200 A Constitutive Model for Time-Dependent Behavior of Clay

Authors: T. N. Mac, B. Shahbodaghkhan, N. Khalili

Abstract:

A new elastic-viscoplastic (EVP) constitutive model is proposed for the analysis of time-dependent behavior of clay. The proposed model is based on the bounding surface plasticity and the concept of viscoplastic consistency framework to establish continuous transition from plasticity to rate dependent viscoplasticity. Unlike the overstress based models, this model will meet the consistency condition in formulating the constitutive equation for EVP model. The procedure of deriving the constitutive relationship is also presented. Simulation results and comparisons with experimental data are then presented to demonstrate the performance of the model.

Keywords: Bounding surface, consistency theory, constitutive model, viscosity.

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199 A Cell-centered Diffusion Finite Volume Scheme and it's Application to Magnetic Flux Compression Generators

Authors: Qiang Zhao, Yina Shi, Guangwei Yuan, Zhiwei Dong

Abstract:

A cell-centered finite volume scheme for discretizing diffusion operators on distorted quadrilateral meshes has recently been designed and added to APMFCG to enable that code to be used as a tool for studying explosive magnetic flux compression generators. This paper describes this scheme. Comparisons with analytic results for 2-D test cases are presented, as well as 2-D results from a test of a "realistic" generator configuration.

Keywords: Cell-centered FVM, distorted meshes, diffusion scheme, MFCG.

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198 Statistical Properties and Performance of Ecological Indices Based On Relative Abundances

Authors: Gebriel M. Shamia

Abstract:

The Improved Generalized Diversity Index (IGDI) has been proposed as a tool that can be used to identify areas that have high conservation value and measure the ecological condition of an area. IGDI is based on the species relative abundances. This paper is concerned with particular attention is given to comparisons involving the MacArthur model of species abundances. The properties and performance of various species indices were assessed. Both IGDI and species richness increased with sampling area according to a power function. IGDI were also found to be acceptable ecological indicators of conditions and consistently outperformed coefficient of conservatism indices.

Keywords: Statistical ecology, MacArthur model, Functional Diversity.

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197 Design Alternatives for Lateral Force-Resisting Systems of Tall Buildings in Dubai, UAE

Authors: Mohammad AlHamaydeh, Sherif Yehia, Nader Aly, Ammar Douba, Layane Hamzeh

Abstract:

Four design alternatives for lateral force-resisting systems of tall buildings in Dubai, UAE are presented. Quantitative comparisons between the different designs are also made. This paper is intended to provide different feasible lateral systems to be used in Dubai in light of the available seismic hazard studies of the UAE. The different lateral systems are chosen in conformance with the International Building Code (IBC). Moreover, the expected behavior of each system is highlighted and light is shed on some of the cost implications associated with lateral system selection.

Keywords: Concrete, Dual, Dubai UAE Seismicity, Special Moment-Resisting Frames (SMRF), Special Shear Wall, Steel

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196 The Effect of Different Compression Schemes on Speech Signals

Authors: Jalal Karam, Raed Saad

Abstract:

This paper studies the effect of different compression constraints and schemes presented in a new and flexible paradigm to achieve high compression ratios and acceptable signal to noise ratios of Arabic speech signals. Compression parameters are computed for variable frame sizes of a level 5 to 7 Discrete Wavelet Transform (DWT) representation of the signals for different analyzing mother wavelet functions. Results are obtained and compared for Global threshold and level dependent threshold techniques. The results obtained also include comparisons with Signal to Noise Ratios, Peak Signal to Noise Ratios and Normalized Root Mean Square Error.

Keywords: Speech Compression, Wavelets.

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195 Analytical Solutions of Three Dimensional Steady-State Heat Transfer in Rectangular Ribs

Authors: Tao Nie, Weiqiang Liu

Abstract:

In order to obtain an accurate result of the heat transfer of the rib in the internal cooling Rectangular channel, using separation of variables, analytical solutions of three dimensional steady-state heat conduction in rectangular ribs are given by solving three dimensional steady-state function of the rectangular ribs. Therefore, we can get solution of three dimensional temperature field in the rib. Based on the solution, we can get how the Bi number affected on heat transfer. Furthermore, comparisons of the analytical and numerical results indicate agreement on temperature field in the rib.

Keywords: variable separation method, analytical solution, rib, heat transfer

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194 Embedded Singly Diagonally Implicit Runge-Kutta –Nystrom Method Order 5(4) for the Integration of Special Second Order ODEs

Authors: Fudziah Ismail

Abstract:

In this paper a new embedded Singly Diagonally Implicit Runge-Kutta Nystrom fourth order in fifth order method for solving special second order initial value problems is derived. A standard set of test problems are tested upon and comparisons on the numerical results are made when the same set of test problems are reduced to first order systems and solved using the existing embedded diagonally implicit Runge-Kutta method. The results suggests the superiority of the new method.

Keywords: Runge-Kutta Nystrom, Special second orderproblems.

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193 A Note on Penalized Power-Divergence Test Statistics

Authors: Aylin Alin

Abstract:

In this paper, penalized power-divergence test statistics have been defined and their exact size properties to test a nested sequence of log-linear models have been compared with ordinary power-divergence test statistics for various penalization, λ and main effect values. Since the ordinary and penalized power-divergence test statistics have the same asymptotic distribution, comparisons have been only made for small and moderate samples. Three-way contingency tables distributed according to a multinomial distribution have been considered. Simulation results reveal that penalized power-divergence test statistics perform much better than their ordinary counterparts.

Keywords: Contingency table, Log-linear models, Penalization, Power-divergence measure, Penalized power-divergence measure.

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192 Operation Assay of an Industrial Single-Source – Single-Detector Gamma CT Using MCNP4C Code Simulation and Experimental Test Comparisons

Authors: M. Ghanadi, M. Rezazadeh*, M. Ardeshiri, R. Gholipour Peyvandi, M. Jafarzadeh, M. Shahriari, M.Rezaei Rad, Z. Gholamzadeh

Abstract:

A 3D industrial computed tomography (CT) manufactured based on a first generation CT systems, single-source – single-detector, was evaluated. Operation accuracy assessment of the manufactured system was achieved using simulation in comparison with experimental tests. 137Cs and 60Co were used as a gamma source. Simulations were achieved using MCNP4C code. Experimental tests of 137Cs were in good agreement with the simulations

Keywords: Gamma source, Industrial CT, MCNP4C, Operation assessment

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191 Regeneration of Spent Catalysts with Ozone

Authors: Jyh-Cherng Chen, Chang-Yong Liu

Abstract:

This study investigates the in-situ regeneration of deactivated Pt-Pd catalyst in a laboratory-scale catalysis reactor. Different regeneration conditions are tested and the activity and characteristics of regenerated catalysts are analyzed. Experimental results show that the conversion efficiencies of C3H6 by different regenerated Pt-Pd catalysts were significantly improved from 77%, 55% and 41% to 86%, 98% and 99%, respectively. The best regeneration conditions was 52ppm ozone, 500oC, and 10min. Regeneration temperature has more influences than ozone concentration and regeneration time. With the comparisons of characteristics of deactivated catalyst and regenerated catalyst, the major poison species (carbon, metals, chloride, and sulfate) on the spent catalysts can be effectively removed by ozone regeneration. 

Keywords: Catalyst, deactivated, ozone, regeneration.

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190 An Analytical Method to Analysis of Foam Drainage Problem

Authors: A. Nikkar, M. Mighani

Abstract:

In this study, a new reliable technique use to handle the foam drainage equation. This new method is resulted from VIM by a simple modification that is Reconstruction of Variational Iteration Method (RVIM). The drainage of liquid foams involves the interplay of gravity, surface tension, and viscous forces. Foaming occurs in many distillation and absorption processes. Results are compared with those of Adomian’s decomposition method (ADM).The comparisons show that the Reconstruction of Variational Iteration Method is very effective and overcome the difficulty of traditional methods and quite accurate to systems of non-linear partial differential equations.

Keywords: Reconstruction of Variational Iteration Method (RVIM), Foam drainage, nonlinear partial differential equation.

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189 Impact of Financial System’s Development on Economic Development: An Empirical Investigation

Authors: Vilma Deltuvaitė

Abstract:

Comparisons of financial development across countries are central to answering many of the questions on factors leading to economic development. For this reason this study analyzes the implications of financial system’s development on country’s economic development. The aim of the article: to analyze the impact of financial system’s development on economic development. The following research methods were used: systemic, logical and comparative analysis of scientific literature, analysis of statistical data, time series model (Autoregressive Distributed Lag (ARDL) Model). The empirical results suggest about positive short and long term effect of stock market development on GDP per capita.

Keywords: Banking sector, economic development, financial system’s development, stock market, private bond market.

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188 Network Analysis in a Natural Perturbed Ecosystem

Authors: Nelson F.F. Ebecken, Gilberto C. Pereira

Abstract:

The objective of this work is to explicit knowledge on the interactions between the chlorophyll-a and nine meroplankton larvae of epibenthonic fauna. The studied case is the Arraial do Cabo upwelling system, Southeastern of Brazil, which provides different environmental conditions. To assess this information a network approach based in probability estimative was used. Comparisons among the generated graphs are made in the light of different water masses, application of Shannon biodiversity index, and the closeness and betweenness centralities measurements. Our results show the main pattern among different water masses and how the core organisms belonging to the network skeleton are correlated to the main environmental variable. We conclude that the approach of complex networks is a promising tool for environmental diagnostic.

Keywords: Coastal upwelling, Ecological networks, Plankton - interactions, Environmental analysis.

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187 On the Use of Correlated Binary Model in Social Network Analysis

Authors: Elsayed A. Habib Elamir

Abstract:

In social network analysis the mean nodal degree and density of the graph can be considered as a measure of the activity of all actors in the network and this is an important property of a graph and for making comparisons among networks. Since subjects in a family or organization are subject to common environment factors, it is prime interest to study the association between responses. Therefore, we study the distribution of the mean nodal degree and density of the graph under correlated binary units. The cross product ratio is used to capture the intra-units association among subjects. Computer program and an application are given to show the benefits of the method.

Keywords: Correlated Binary data, cross product ratio, densityof the graph, multiplicative binomial distribution.

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186 The Performance of the Character-Access on the Checking Phase in String Searching Algorithms

Authors: Mahmoud M. Mhashi

Abstract:

A new algorithm called Character-Comparison to Character-Access (CCCA) is developed to test the effect of both: 1) converting character-comparison and number-comparison into character-access and 2) the starting point of checking on the performance of the checking operation in string searching. An experiment is performed; the results are compared with five algorithms, namely, Naive, BM, Inf_Suf_Pref, Raita, and Circle. With the CCCA algorithm, the results suggest that the evaluation criteria of the average number of comparisons are improved up to 74.0%. Furthermore, the results suggest that the clock time required by the other algorithms is improved in range from 28% to 68% by the new CCCA algorithm

Keywords: Pattern matching, string searching, charactercomparison, character-access, and checking.

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185 New Fourth Order Explicit Group Method in the Solution of the Helmholtz Equation

Authors: Norhashidah Hj. Mohd Ali, Teng Wai Ping

Abstract:

In this paper, the formulation of a new group explicit method with a fourth order accuracy is described in solving the two dimensional Helmholtz equation. The formulation is based on the nine-point fourth order compact finite difference approximation formula. The complexity analysis of the developed scheme is also presented. Several numerical experiments were conducted to test the feasibility of the developed scheme. Comparisons with other existing schemes will be reported and discussed. Preliminary results indicate that this method is a viable alternative high accuracy solver to the Helmholtz equation.

Keywords: Explicit group method, finite difference, Helmholtz equation, five-point formula, nine-point formula.

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184 A Hypermap for Supply Chain Management

Authors: James K. Ho

Abstract:

We present a prototype interactive (hyper) map of strategic, tactical, and logistic options for Supply Chain Management. The map comprises an anthology of options, broadly classified within the strategic spectrum of efficiency versus responsiveness, and according to logistic and cross-functional drivers. They are exemplified by cases in diverse industries. We seek to get all these information and ideas organized to help supply chain managers identify effective choices for specific business environments. The key and innovative linkage we introduce is the configuration of competitive forces. Instead of going through seemingly endless and isolated cases and wondering how one can borrow from them, we aim to provide a guide by force comparisons. The premise is that best practices in a different industry facing similar forces may be a most productive resource in supply chain design and planning. A prototype template is demonstrated.

Keywords: Competitive forces, strategic innovation, supplychain management.

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183 The Comparisons of Average Outgoing Quality Limit between the MCSP-2-C and MCSP-C

Authors: P. Guayjarernpanishkand, T. Mayureesawan

Abstract:

This paper presents a comparison of average outgoing quality limit of the MCSP-2-C plan with MCSP-C when MCSP-2-C has been developed from MCSP-C. The parameters used in MCSP-2- C are: i (the clearance number), c (the acceptance number), m (the number of conforming units to be found before allowing c nonconforming units in the sampling inspection), f1 and f2 (the sampling frequency at level 1 and 2, respectively). The average outgoing quality limit (AOQL) values from two plans were compared and we found that for all sets of i, r, and c values, MCSP-2-C gives higher values than MCSP-C. For all sets of i, r, and c values, the average outgoing quality values of MCSP-C and MCSP-2-C are similar when p is low or high but is difference when p is moderate.

Keywords: average outgoing quality, average outgoing quality limit, continuous sampling plan.

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182 Empirical Analysis of Velocity Behavior for Collaborative Robots in Transient Contact Cases

Authors: C. Schneider, M. M. Seizmeir, T. Suchanek, M. Hutter-Mironovová, M. Bdiwi, M. Putz

Abstract:

In this paper, a suitable measurement setup is presented to conduct force and pressure measurements for transient contact cases at the example of lathe machine tending. Empirical measurements were executed on a selected collaborative robot’s behavior regarding allowable operating speeds under consideration of sensor- and workpiece-specific factors. Comparisons between the theoretic calculations proposed in ISO/TS 15066 and the practical measurement results reveal a basis for future research. With the created database, preliminary risk assessment and economic assessment procedures of collaborative machine tending cells can be facilitated.

Keywords: biomechanical thresholds, collaborative robots, force and pressure measurements, machine tending, transient contact

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181 The Negative Effect of Traditional Loops Style on the Performance of Algorithms

Authors: Mahmoud Moh'd Mhashi

Abstract:

A new algorithm called Character-Comparison to Character-Access (CCCA) is developed to test the effect of both: 1) converting character-comparison and number-comparison into character-access and 2) the starting point of checking on the performance of the checking operation in string searching. An experiment is performed using both English text and DNA text with different sizes. The results are compared with five algorithms, namely, Naive, BM, Inf_Suf_Pref, Raita, and Cycle. With the CCCA algorithm, the results suggest that the evaluation criteria of the average number of total comparisons are improved up to 35%. Furthermore, the results suggest that the clock time required by the other algorithms is improved in range from 22.13% to 42.33% by the new CCCA algorithm.

Keywords: Pattern matching, string searching, charactercomparison, character-access, text type, and checking

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180 A Boundary Fitted Nested Grid Model for Modelling Tsunami Propagation of 2004 Indonesian Tsunami along Southern Thailand

Authors: Md. Fazlul Karim, Esa Al-Islam

Abstract:

This paper describes the development of a boundary fitted nested grid (BFNG) model to compute tsunami propagation of 2004 Indonesian tsunami in Southern Thailand coastal waters. We develop a numerical model employing the shallow water nested model and an orthogonal boundary fitted grid to investigate the tsunami impact on the Southern Thailand due to the Indonesian tsunami of 2004. Comparisons of water surface elevation obtained from numerical simulations and field measurements are made.

Keywords: Boundary-fitted nested grid model, finite difference method, Indonesian tsunami of 2004, Southern Thailand.

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179 CFD Simulation of Solid-Liquid Stirred Tank with Rushton Turbine and Propeller Impeller

Authors: M. H. Pour, V. M. Nansa, M. Saberi, A. M. Ghanadi, A. Aghayari, M. Mirzajanzadeh

Abstract:

Stirred tanks have applications in many chemical processes where mixing is important for the overall performance of the system. In present work 5%v of the tank is filled by solid particles with diameter of 700 m that Rushton Turbine and Propeller impeller is used for stirring. An Eulerian-Eulerian Multi Fluid Model coupled and for modeling rotating of impeller, moving reference frame (MRF) technique was used and standard-k- model was selected for turbulency. Flow field, radial velocity and axial distribution of solid for both of impellers was investigation and comparison. Comparisons of simulation results between Rushton Turbine and propeller impeller shows that final quality of solid-liquid slurry in different rotating speed for propeller impeller is better than the Rushton Turbine.

Keywords: CFD, Particle Velocity, Propeller Impeller, Rushton Turbine.

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178 The Interaction between Human and Environment on the Perspective of Environmental Ethics

Authors: Mella Ismelina Farma Rahayu

Abstract:

Environmental problems could not be separated from unethical human perspectives and behaviors toward the environment. There is a fundamental error in the philosophy of people’s perspective about human and nature and their relationship with the environment, which in turn will create an inappropriate behavior in relation to the environment. The aim of this study is to investigate and to understand the ethics of the environment in the context of humans interacting with the environment by using the hermeneutic approach. The related theories and concepts collected from literature review are used as data, which were analyzed by using interpretation, critical evaluation, internal coherence, comparisons, and heuristic techniques. As a result of this study, there will be a picture related to the interaction of human and environment in the perspective of environmental ethics, as well as the problems of the value of ecological justice in the interaction of humans and environment. We suggest that the interaction between humans and environment need to be based on environmental ethics, in a spirit of mutual respect between humans and the natural world.

Keywords: The environment, environmental ethics, the interaction, value.

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177 A Decision Support Model for Bank Branch Location Selection

Authors: Nihan Cinar

Abstract:

Location selection is one of the most important decision making process which requires to consider several criteria based on the mission and the strategy. This study-s object is to provide a decision support model in order to help the bank selecting the most appropriate location for a bank-s branch considering a case study in Turkey. The object of the bank is to select the most appropriate city for opening a branch among six alternatives in the South-Eastern of Turkey. The model in this study was consisted of five main criteria which are Demographic, Socio-Economic, Sectoral Employment, Banking and Trade Potential and twenty one subcriteria which represent the bank-s mission and strategy. Because of the multi-criteria structure of the problem and the fuzziness in the comparisons of the criteria, fuzzy AHP is used and for the ranking of the alternatives, TOPSIS method is used.

Keywords: MCDM, bank branch location, fuzzy AHP, TOPSIS.

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176 A Fuzzy Predictive Filter for Sinusoidal Signals with Time-Varying Frequencies

Authors: X. Z. Gao, S. J. Ovaska, X. Wang

Abstract:

Prediction of sinusoidal signals with time-varying frequencies has been an important research topic in power electronics systems. To solve this problem, we propose a new fuzzy predictive filtering scheme, which is based on a Finite Impulse Response (FIR) filter bank. Fuzzy logic is introduced here to provide appropriate interpolation of individual filter outputs. Therefore, instead of regular 'hard' switching, our method has the advantageous 'soft' switching among different filters. Simulation comparisons between the fuzzy predictive filtering and conventional filter bank-based approach are made to demonstrate that the new scheme can achieve an enhanced prediction performance for slowly changing sinusoidal input signals.

Keywords: Predictive filtering, fuzzy logic, sinusoidal signals, time-varying frequencies.

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175 A Purpose Based Usage Access Control Model

Authors: Lili Sun, Hua Wang

Abstract:

As privacy becomes a major concern for consumers and enterprises, many research have been focused on the privacy protecting technology in recent years. In this paper, we present a comprehensive approach for usage access control based on the notion purpose. In our model, purpose information associated with a given data element specifies the intended use of the subjects and objects in the usage access control model. A key feature of our model is that it allows when an access is required, the access purpose is checked against the intended purposes for the data item. We propose an approach to represent purpose information to support access control based on purpose information. Our proposed solution relies on usage access control (UAC) models as well as the components which based on the notions of the purpose information used in subjects and objects. Finally, comparisons with related works are analyzed.

Keywords: Purpose, privacy, access control, authorization

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174 Comparison of Different PWM Switching Modes of BLDC Motor as Drive Train of Electric Vehicles

Authors: A. Tashakori, M. Ektesabi

Abstract:

Electric vehicle (EV) is one of the effective solutions to control emission of greenhouses gases in the world. It is of interest for future transportation due to its sustainability and efficiency by automotive manufacturers. Various electrical motors have been used for propulsion system of electric vehicles in last decades. In this paper brushed DC motor, Induction motor (IM), switched reluctance motor (SRM) and brushless DC motor (BLDC) are simulated and compared. BLDC motor is recommended for high performance electric vehicles. PWM switching technique is implemented for speed control of BLDC motor. Behavior of different modes of PWM speed controller of BLDC motor are simulated in MATLAB/SIMULINK. BLDC motor characteristics are compared and discussed for various PWM switching modes under normal and inverter fault conditions. Comparisons and discussions are verified through simulation results.

Keywords: BLDC motor, PWM switching technique, in-wheel technology, electric vehicle.

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173 Simulation of Natural Convection Flow in an Inclined open Cavity using Lattice Boltzmann Method

Authors: H. Sajjadi, M. Gorji, GH.R. Kefayati, D. D. Ganji, M. Shayan nia

Abstract:

In this paper effects of inclination angle on natural convection flow in an open cavity has been analyzed with Lattice Boltzmann Method (LBM).The angle of inclination varied from θ= - 45° to 45° with 15° intervals. Study has been conducted for Rayleigh numbers (Ra) 104 to 106. The comparisons show that the average Nusselt number increases with growth of Rayleigh number and the average Nusselt number increase as inclination angles increases at Ra=104.At Ra=105 and Ra=106 the average Nusselt number enhance as inclination angels varied from θ= -45° to θ= 0° and decrease as inclination angels increase in θ= 0° to θ= 45°.

Keywords: Lattice Boltzmann Method, Inclination angle, Opencavity, Natural convection

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172 An Analytical Solution for Vibration of Elevator Cables with Small Bending Stiffness

Authors: R. Mirabdollah Yani, E. Darabi

Abstract:

Responses of the dynamical systems are highly affected by the natural frequencies and it has a huge impact on design and operation of high-rise and high-speed elevators. In the present paper, the variational iteration method (VIM) is employed to investigate better understanding the dynamics of elevator cable as a single-degree-of-freedom (SDOF) swing system. Comparisons made among the results of the proposed closed-form analytical solution, the traditional numerical iterative time integration solution, and the linearized governing equations confirm the accuracy and efficiency of the proposed approach. Furthermore, based on the results of the proposed closed-form solution, the linearization errors in calculating the natural frequencies in different cases are discussed.

Keywords: variational iteration method (VIM), cable vibration, closed-form solution

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