Search results for: fully differential transconductor

Authors: E. G. Bautista, J. M. Reyes, O. Bautista, J. C. Arcos

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In this work, we analyze the deformation of surface waves in shallow flows conditions, propagating in a channel of slowly varying cross-section. Based on a singular perturbation technique, the main purpose is to predict the motion of waves by using a dimensionless formulation of the governing equations, considering that the longitudinal variation of the transversal section obey a power-law distribution. We show that the spatial distribution of the waves in the varying cross-section is a function of a kinematic parameter,κ , and two geometrical parameters εh and w ε . The above spatial behavior of the surface elevation is modeled by an ordinary differential equation. The use of single formulas to model the varying cross sections or transitions considered in this work can be a useful approximation to natural or artificial geometrical configurations.

Keywords: Surface waves, Asymptotic solution, Power law function, Non-dispersive waves.

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Authors: Charalampos Saridakis, Stelios Tsafarakis

Abstract:

Although environmental concern is on the rise across Europe, current market data indicate that adoption rates of environmentally friendly vehicles remain extremely low. Against this background, the aim of this paper is to a) assess preferences of European consumers for clean-fuel cars and their characteristics and b) design car lines that optimize the combination of fuel types among models in the line-up. In this direction, the authors introduce a new evolutionary mechanism and implement it to stated-preference data derived from a large-scale choice-based conjoint experiment that measures consumer preferences for various factors affecting clean-fuel vehicle (CFV) adoption. The proposed two-step methodology provides interesting insights into how new and existing fuel-types can be combined in a car line that maximizes customer satisfaction.

Keywords: Clean-fuel vehicles, product line design, conjoint analysis, choice experiment, differential evolution.

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Authors: Nan Jiang, Jian Wang

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Random Oracle Model (ROM) is an effective method for measuring the practical security of cryptograph. In this paper, we try to use it into information hiding system (IHS). Because IHS has its own properties, the ROM must be modified if it is used into IHS. Firstly, we fully discuss why and how to modify each part of ROM respectively. The main changes include: 1) Divide the attacks that IHS may be suffered into two phases and divide the attacks of each phase into several kinds. 2) Distinguish Oracles and Black-boxes clearly. 3) Define Oracle and four Black-boxes that IHS used. 4) Propose the formalized adversary model. And 5) Give the definition of judge. Secondly, based on ROM of IHS, the security against known original cover attack (KOCA-KOCA-security) is defined. Then, we give an actual information hiding scheme and prove that it is KOCA-KOCA-secure. Finally, we conclude the paper and propose the open problems of further research.

Keywords: Attack, Information Hiding, Provable Security, Random Oracle Model.

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Authors: F. Nkontchou Ngongang, M. Tchawe Tchawe, B. Djeumako, B. Kenmeugne

Abstract:

In this work, the flow structure in the Songloulou dam, is visualized in a time interval to observe the different fluid layers in our structure. Firstly, the three-dimensional modelling of the penstock is carried out in the software Gambit, followed by calculations in Fluent that proceeds introduction of boundary conditions. After calculation, we identified four periods corresponding to four regimes. In the first, spanning from 0.00 to 1.50s, we have the non-developed hydraulically rough turbulent regime, characterized by abrupt variations with modifications of the velocity fields. The second extends from 1.50 to 3.50s, where we have the transition regime characterized by slight variations and modifications of the velocity fields but with a great difference of the values of the current lines. From 3.50 to 5.00s, we encounter the third, which is the fully developed turbulent hydraulically rough regime, characterized by fields that vary no more, but have minute differences in the streamlines. The last period is from 5.00s and more, where we have a flow that is almost stationary, hence there are no changes in the fields.

Keywords: Unsteady flow, penstock, friction coefficient, hydroelectric dam.

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Authors: Taewon Seo

Abstract:

The characteristics of physiological blood flow in human carotid arterial bifurcation model have been numerically studied using a fully coupled fluid-structure interaction (FSI) analysis. This computational model with the fluid-structure interaction is constructed to investigate the flow characteristics and wall shear stress in the carotid artery. As the flow begins to decelerate after the peak flow, a large recirculation zone develops at the non-divider wall of both internal carotid artery (ICA) and external carotid artery (ECA) in FSI model due to the elastic energy stored in the expanding compliant wall. The calculated difference in wall shear stress (WSS) in both Non-FSI and FSI models is a range of between 5 and 11% at the mean WSS. The low WSS corresponds to regions of carotid artery that are more susceptible to atherosclerosis.

Keywords: Carotid artery, Fluid-structure interaction, Hemodynamics, Wall shear stress.

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Authors: Lorenzo Putzu, Cecilia Di Ruberto

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The counting and analysis of blood cells allows the evaluation and diagnosis of a vast number of diseases. In particular, the analysis of white blood cells (WBCs) is a topic of great interest to hematologists. Nowadays the morphological analysis of blood cells is performed manually by skilled operators. This involves numerous drawbacks, such as slowness of the analysis and a nonstandard accuracy, dependent on the operator skills. In literature there are only few examples of automated systems in order to analyze the white blood cells, most of which only partial. This paper presents a complete and fully automatic method for white blood cells identification from microscopic images. The proposed method firstly individuates white blood cells from which, subsequently, nucleus and cytoplasm are extracted. The whole work has been developed using MATLAB environment, in particular the Image Processing Toolbox.

Keywords: Automatic detection, Biomedical image processing, Segmentation, White blood cell analysis.

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Authors: Byung-Soo Shin, Nam-Seok Kim, Sang-Kyu Lee, O-Hyun Keum

Abstract:

This analysis investigates the distortion of flow measurement and the increase of cavitation along orifice flowmeter. The analysis using the numerical method (CFD) validated the distortion of flow measurement through the inlet velocity profile considering the convergence and grid dependency. Realizable k-e model was selected and y+ was about 50 in this numerical analysis. This analysis also estimated the vulnerability of cavitation effect due to inlet velocity profile. The investigation concludes that inclined inlet velocity profile could vary the pressure which was measured at pressure tab near pipe wall and it led to distort the pressure values ranged from -3.8% to 5.3% near the orifice plate and to make the increase of cavitation. The investigation recommends that the fully developed inlet velocity flow is beneficial to accurate flow measurement in orifice flowmeter.

Keywords: Orifice, k-e model, CFD

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Authors: Marko Čular

Abstract:

The aim of this paper is to raise general awareness of transparency importance for audit firms and for audit services’ users. This paper analyzes transparency of audit firms that audited financial statements of listed companies, for year 2011 and 2012. We use this two years because in the meantime Code of Ethics for Professional Accountants has been adopted. This paper investigates whether transparency reports of audit firms are in accordance with the Croatian Audit Act and whether there is a difference on transparency in observed years. For this paper quality index of transparency report and financial indicators of audit firms are used to get conclusion about condition of audit firms transparency reporting. Results of our study indicate that audit firms are not fully transparent, looking for both years. Transparency of audit firms in 2012 has improved significantly, compared with transparency in 2011.

Keywords: Transparency report, Index quality of transparency report, Croatian Audit Act, Code of Ethics for Professional Accountants.

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Authors: S. Damodaran, T. V. S.Sekhar

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The motion of a sphere moving along the axis of a rotating viscous fluid is studied at high Reynolds numbers and moderate values of Taylor number. The Higher Order Compact Scheme is used to solve the governing Navier-Stokes equations. The equations are written in the form of Stream function, Vorticity function and angular velocity which are highly non-linear, coupled and elliptic partial differential equations. The flow is governed by two parameters Reynolds number (Re) and Taylor number (T). For very low values of Re and T, the results agree with the available experimental and theoretical results in the literature. The results are obtained at higher values of Re and moderate values of T and compared with the experimental results. The results are fourth order accurate.

Keywords: Navier_Stokes equations, Taylor number, Reynolds number, Higher order compact scheme, Rotating Fluid.

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Authors: A. A. James, A. O. Adesanya, M. R. Odekunle, D. G. Yakubu

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This paper examines the development of one step, five hybrid point method for the solution of first order initial value problems. We adopted the method of collocation and interpolation of power series approximate solution to generate a continuous linear multistep method. The continuous linear multistep method was evaluated at selected grid points to give the discrete linear multistep method. The method was implemented using a constant order predictor of order seven over an overlapping interval. The basic properties of the derived corrector was investigated and found to be zero stable, consistent and convergent. The region of absolute stability was also investigated. The method was tested on some numerical experiments and found to compete favorably with the existing methods.

Keywords: Interpolation, Approximate Solution, Collocation, Differential system, Half step, Converges, Block method, Efficiency.

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Authors: Pavla Ruzickova, Petr Teply

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There are many debates now regarding undervalued and overvalued currencies currently traded on the world financial market. This paper contributes to these debates from a theoretical point of view. We present the three most commonly used methods of estimating the equilibrium real effective exchange rate (REER): macroeconomic balance approach, external sustainability approach and equilibrium real effective exchange rate approach in the reduced form. Moreover, we discuss key concepts of the calculation of the real exchange rate (RER) based on applied explanatory variables: nominal exchange rates, terms of trade and tradable and non-tradable goods. Last but not least, we discuss the three main driving forces behind real exchange rates movements which include terms of trade, relative productivity growth and the interest rate differential.

Keywords: real exchange rate, real effective exchange rate, foreign exchange, terms of trade

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Authors: Nam-Seok Kim, Sang-Kyu Lee, Byung-Soo Shin, O-Hyun Keum

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The present paper represents a methodology for investigating flow characteristics near orifice plate by using a commercial computational fluid dynamics code. The flow characteristics near orifice plate which is located in the auxiliary feedwater system were modeled via three different levels of grid and four different types of Reynolds Averaged Navier-Stokes (RANS) equations with proper near-wall treatment. The results from CFD code were compared with experimental data in terms of differential pressure through the orifice plate. In this preliminary study, the Realizable k-ε and the Reynolds stress models with enhanced wall treatment were suitable to analyze flow characteristics near orifice plate, and the results had a good agreement with experimental data.

Keywords: Auxiliary Feedwater, Computational Fluid Dynamics, Orifice, Nuclear Power Plant

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Authors: S. Alotaibi, D. Roussinov

Abstract:

Mobile government services implementation faces several challenges in developing countries. This paper studies some of those challenges in the context of Saudi Arabia. The study aims to investigate factors affecting m-government acceptance in Saudi Arabia, including ease of use, usefulness, service quality, trust, intention to use and users’ satisfaction. Our investigation will help in integrating the m-government services in citizens’ everyday life. We collected and analyzed our data from focus groups. These focus groups are from King Saud University and Imam Muhammed Bin Saud University, so the samples size are five and seven participants, respectively. We found that there are some factors to identifying citizen requirements to Saudi mobile government services. These services should be easy to use and not require too much effort. Also, these services must be fully trusted.

Keywords: E-government, M-government, focus group, Saudi mobile government services.

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Authors: Nasser Mohamed Ramli, Mohamad Syafiq Mohamad

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Many types of controllers were applied on the continuous stirred tank reactor (CSTR) unit to control the temperature. In this research paper, Proportional-Integral-Derivative (PID) controller are compared with Fuzzy Logic controller for temperature control of CSTR. The control system for temperature non-isothermal of a CSTR will produce a stable response curve to its set point temperature. A mathematical model of a CSTR using the most general operating condition was developed through a set of differential equations into S-function using MATLAB. The reactor model and S-function are developed using m.file. After developing the S-function of CSTR model, User-Defined functions are used to link to SIMULINK file. Results that are obtained from simulation and temperature control were better when using Fuzzy logic control compared to PID control.

Keywords: CSTR, temperature, PID, fuzzy logic.

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Authors: Taneli Eisto, Venlakaisa Hölttä

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Customer-supplier collaboration enables firms to achieve greater success than acting independently. Nevertheless, not many firms have fully utilized the potential of collaboration. This paper presents organizational and human related success factors for collaboration in manufacturing supply chains in casting industry. Our research approach was a case study including multiple cases. Data was gathered by interviews and group discussions in two different research projects. In the first research project we studied seven firms and in the second five. It was found that the success factors are interrelated, in other words, organizational and human factors together enable success but not any of them alone. Some of the found success factors are a culture of following agreements, and a speed of informing the partner about changes affecting to the product or the delivery chain.

Keywords: Casting industry, collaboration success factors, customer-supplier collaboration, supply chain collaboration.

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Authors: Liping Zhang, Kelin Li

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In this paper, a class of impulsive BAM fuzzy cellular neural networks with time delays in the leakage terms is formulated and investigated. By establishing a delay differential inequality and M-matrix theory, some sufficient conditions ensuring the existence, uniqueness and global exponential stability of equilibrium point for impulsive BAM fuzzy cellular neural networks with time delays in the leakage terms are obtained. In particular, a precise estimate of the exponential convergence rate is also provided, which depends on system parameters and impulsive perturbation intention. It is believed that these results are significant and useful for the design and applications of BAM fuzzy cellular neural networks. An example is given to show the effectiveness of the results obtained here.

Keywords: Global exponential stability, bidirectional associative memory, fuzzy cellular neural networks, leakage delays, impulses.

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Authors: Hiroyuki Ohsaki, Makoto Imase

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In Grid computing, a data transfer protocol called GridFTP has been widely used for efficiently transferring a large volume of data. Currently, two versions of GridFTP protocols, GridFTP version 1 (GridFTP v1) and GridFTP version 2 (GridFTP v2), have been proposed in the GGF. GridFTP v2 supports several advanced features such as data streaming, dynamic resource allocation, and checksum transfer, by defining a transfer mode called X-block mode. However, in the literature, effectiveness of GridFTP v2 has not been fully investigated. In this paper, we therefore quantitatively evaluate performance of GridFTP v1 and GridFTP v2 using mathematical analysis and simulation experiments. We reveal the performance limitation of GridFTP v1, and quantitatively show effectiveness of GridFTP v2. Through several numerical examples, we show that by utilizing the data streaming feature, the average file transfer time of GridFTP v2 is significantly smaller than that of GridFTP v1.

Keywords: Grid Computing, GridFTP, Performance Evaluation, Queuing Theory.

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Authors: Jianwei Wang, Timo Korhonen, Yuping Zhao

Abstract:

Cross layer optimization based on utility functions has been recently studied extensively, meanwhile, numerous types of utility functions have been examined in the corresponding literature. However, a major drawback is that most utility functions take a fixed mathematical form or are based on simple combining, which can not fully exploit available information. In this paper, we formulate a framework of cross layer optimization based on Adaptively Weighted Utility Functions (AWUF) for fairness balancing in OFDMA networks. Under this framework, a two-step allocation algorithm is provided as a sub-optimal solution, whose control parameters can be updated in real-time to accommodate instantaneous QoS constrains. The simulation results show that the proposed algorithm achieves high throughput while balancing the fairness among multiple users.

Keywords: OFDMA, Fairness, AWUF, QoS.

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Authors: Wondwosen Teshome B.

Abstract:

One of the approaches to democratization is the fostering of civil society organizations. In Africa, civil society organizations did not fully play their role in the continent-s democratization process due to many factors including the repressive regulations imposed on them by governing parties. In Ethiopia, for the first time in the country-s political history, the civil society played a very active role in the 2005 multi-party election. The involvement of the civil society in this election has far-reaching consequences. One of the objectives of this paper is to assess the consequences of such involvement for both the civil society and the political society in the country. The paper also examines the peculiarities of civil society formation in Africa in general, and in Ethiopia in particular by assessing both the “traditional" and “modern" civil society organizations.

Keywords: Africa, Civil Society, CSO, Democratization, Election, Ethiopia, NGO, Western donors.

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Authors: N.S. Tomer, Phool Singh, Manoj Kumar

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The flow and heat transfer characteristics for natural convection along an inclined plate in a saturated porous medium with an applied magnetic field have been studied. The fluid viscosity has been assumed to be an inverse function of temperature. Assuming temperature vary as a power function of distance. The transformed ordinary differential equations have solved by numerical integration using Runge-Kutta method. The velocity and temperature profile components on the plate are computed and discussed in detail for various values of the variable viscosity parameter, inclination angle, magnetic field parameter, and real constant (λ). The results have also been interpreted with the aid of tables and graphs. The numerical values of Nusselt number have been calculated for the mentioned parameters.

Keywords: Heat Transfer, Magnetic Field, Porosity, Viscosity

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Authors: Faruk Fırat Çalım, Nurullah Karaca, Hakan Tacettin Türker

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In this study, out-of-plane free vibrations of a circular rods is investigated theoretically. The governing equations for naturally twisted and curved spatial rods are obtained using Timoshenko beam theory and rewritten for circular rods. Effects of the axial and shear deformations are considered in the formulations. Ordinary differential equations in scalar form are solved analytically by using transfer matrix method. The circular rods of the mass matrix are obtained by using straight rod of consistent mass matrix. Free vibrations frequencies obtained by solving eigenvalue problem. A computer program coded in MATHEMATICA language is prepared. Circular beams are analyzed through various examples for free vibrations analysis. Results are compared with ANSYS results based on finite element method and available in the literature.

Keywords: Circular rod, Out-of-plane free vibration analysis, Transfer Matrix Method.

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Authors: J. Miao, C. W. Leung, C. S. Cheung, R. C. K. Leung

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The present project was conducted with the circumferential-fuel-jets inverse diffusion flame (CIDF) burner burning liquefied petroleum gas (LPG) enriched with 50% of hydrogen fuel (H2). The range of stable operation of the CIDF burner in terms of Reynolds number (from laminar to turbulent flow regions), equivalence ratio and fuel jet velocity of LPG of the 50% H2-LPG mixed fuel was identified. Experiments were also carried out to investigate the flame structures of the LPG flame and LPG enriched H2 flame. Experimental results obtained from these two flames were compared to fully explore the influence of hydrogen addition on flame stability. Flame heights obtained by burning these two kinds of fuels at various equivalence ratios were compared and correlated with the Global Momentum Ratio (GMR).

Keywords: Flame stability, hydrogen enriched LPG, inverse diffusion flame.

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Authors: H. Sezgin, O. B. Berkalp, R. Mishra, J. Militky

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In the last few decades, due to their advanced properties, there has been an increasing interest in hybrid composite materials. In this study, the effect of different stacking sequences of jute and carbon fabric plies on dynamic mechanical properties of composite laminates were investigated. Vacuum bagging system was used to fabricate the composite samples. Each composite laminate was reinforced with two plies of jute fabric and two plies of carbon fabric by varying the position of layers. Dynamic mechanical analyzer (DMA) was used to examine the dynamic mechanical properties of composite laminates with increasing temperature. Results showed that the composite sample, which has carbon fabric at the outer layers, has the highest storage and loss modulus. Besides, it was observed that glass transition temperature (T_g) of samples are close to each other and at about 75 °C.

Keywords: Differential scanning calorimetry dynamic mechanical analysis, textile reinforced composites, thermogravimetric analysis.

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Authors: L. Sterken, S. Sebben, L. Löfdahl

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In this paper an alternative visualisation approach of the wake behind different vehicle body shapes with simplified and fully-detailed underbody has been proposed and analysed. This allows for a more clear distinction among the different wake regions. This visualisation is based on a transformation of the cartesian coordinates of a chosen wake plane to polar coordinates, using as filter velocities lower than the freestream. This transformation produces a polar wake plot that enables the division and quantification of the wake in a number of sections. In this paper, local drag has been used to visualise the drag contribution of the flow by the different sections. Visually, a balanced wake can be observed by the concentric behaviour of the polar plots. Alternatively, integration of the local drag of each degree section as a ratio of the total local drag yields a quantifiable approach of the wake uniformity, where different sections contribute equally to the local drag, with the exception of the wheels.

Keywords: Coordinate transformation, ground vehicle, local drag, wake.

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Authors: A. Radzevičius, P. Viškelis, J. Viškelis, R. Karklelienė, D. Juškevičienė

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Tomato (Lycopersicon esculentum Mill.) hybrid 'Brooklyn' was investigated at the LRCAF Institute of Horticulture. For investigation, five green tomatoes, which were grown on vine, were selected. Color measurements were made in the greenhouse with the same selected tomato fruits (fruits were not harvested and were growing and ripening on tomato vine through all experiment) in every two days while tomatoes fruits became fully ripen. Study showed that color index L has tendency to decline and established determination coefficient (R²) was 0.9504. Also, hue angle has tendency to decline during tomato fruit ripening on vine and it’s coefficient of determination (R²) reached – 0.9739. Opposite tendency was determined with color index a*, which has tendency to increase during tomato ripening and that was expressed by polynomial trendline where coefficient of determination (R²) reached – 0.9592.

Keywords: Color, color index, ripening, tomato.

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Authors: Rong-Jong Wai, Chia-Ming Liu

Abstract:

Generally speaking, the mobile robot is capable of sensing its surrounding environment, interpreting the sensed information to obtain the knowledge of its location and the environment, planning a real-time trajectory to reach the object. In this process, the issue of obstacle avoidance is a fundamental topic to be challenged. Thus, an adaptive path-planning control scheme is designed without detailed environmental information, large memory size and heavy computation burden in this study for the obstacle avoidance of a mobile robot. In this scheme, the robot can gradually approach its object according to the motion tracking mode, obstacle avoidance mode, self-rotation mode, and robot state selection. The effectiveness of the proposed adaptive path-planning control scheme is verified by numerical simulations of a differential-driving mobile robot under the possible occurrence of obstacle shapes.

Keywords: Adaptive Path Planning, Mobile Robot ObstacleAvoidance

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Authors: Wiem Gadri

Abstract:

This study delves into the intriguing properties of Pisot and Salem numbers within the framework of formal Laurent series over finite fields, a domain where these numbers’ spectral characteristics, Λm(β) and lm(β), have yet to be fully explored. Utilizing a methodological approach that combines algebraic number theory with the analysis of power series, we extend the foundational work of Erdos, Joo, and Komornik to this setting. Our research uncovers bounds for lm(β), revealing how these depend on the degree of the minimal polynomial of β and thus offering a characterization of Pisot and Salem formal power series. The findings significantly contribute to our understanding of these numbers, highlighting their distribution and properties in the context of formal power series. This investigation not only bridges number theory with formal power series analysis but also sets the stage for further interdisciplinary research in these areas.

Keywords: Pisot numbers, Salem numbers, Formal power series, Minimal polynomial degree.

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Authors: Awni H. Alkhazaleh, Baljinder K. Kandola

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In this study, a form-stable composite Paraffin/Nanoclay (PA-NC) has been prepared by absorbing PA into porous particles of NC to be used for low-temperature latent heat thermal energy storage. The leakage test shows that the maximum mass fraction of PA that can be incorporated in NC without leakage is 60 wt.%. Differential scanning calorimetry (DSC) has been used to measure the thermal properties of the PA and PA-NC both before and after incorporation in plasterboard (PL). The mechanical performance of the samples has been evaluated in flexural mode. The thermal energy storage performance has been studied using a small test chamber (100 mm × 100 mm × 100 mm) made from 10 mm thick PL and measuring the temperatures using thermocouples. The flammability of the PL+PL-NC has been discussed using a cone calorimeter. The results indicate that the form composite PA has good potential for use as thermal energy storage materials in building applications.

Keywords: Flammability, paraffin, plasterboard, thermal energy storage.

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Authors: Marco Soares dos Santos, Jorge Augusto Ferreira, Camila Nicola Boeri, Fernando Neto da Silva

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The present paper proposes high performance nonlinear force controllers for a servopneumatic real-time fatigue test machine. A CompactRIO® controller was used, being fully programmed using LabVIEW language. Fuzzy logic control algorithms were evaluated to tune the integral and derivative components in the development of hybrid controllers, namely a FLC P and a hybrid FLC PID real-time-based controllers. Their behaviours were described by using state diagrams. The main contribution is to ensure a smooth transition between control states, avoiding discrete transitions in controller outputs. Steady-state errors lower than 1.5 N were reached, without retuning the controllers. Good results were also obtained for sinusoidal tracking tasks from 1/¤Ç to 8/¤Ç Hz.

Keywords: Hybrid Fuzzy Selecting, Control, Range Controllers, Servopneumatic Fatigue System.

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Authors: K. Kuntanoo, S. Promkotra, P. Kaewkannetra

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According to synthetic plastics obtained from petroleum cause some environmental problems. Therefore, degradable plastics become widely used and studied for replacing the synthetic plastic waste. A biopolymer of poly hydroxybutyrate-co-hydroxyvalerate (PHBV) is subgroups of a main kind of polyhydroxyalkanoates (PHAs). Naturally, PHBV is hard, brittle and low flexible while natural rubber (NR) is high elastic latex. Then, they are blended and the biodegradation of the blended PHBV and NR films were examined in soil environment. The results showed that the degradation occurs predominantly in the bulk of the samples. The order of biodegradability was shown as follows: PHBV> PHBV/NR> NR. After biodegradation, the blended films were characterized by appearance analysis such as Scanning Electron Microscope (SEM), Fourier transform infrared spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC). It was found that the biodegradation mainly occurred at the polymer surface.

Keywords: Biodegradation, polyhydroxyalkanoates (PHAs), Polyhydroxybutyrate-co-hydroxyvalerate (PHBV), natural rubber (NR).

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