**Commenced**in January 2007

**Frequency:**Monthly

**Edition:**International

**Paper Count:**143

# Search results for: constant coefficients

##### 143 Determine of Constant Coefficients to RelateTotal Dissolved Solids to Electrical Conductivity

**Authors:**
M. Siosemarde,
F. Kave,
E. Pazira,
H. Sedghi,
S. J. Ghaderi

**Abstract:**

**Keywords:**
constant coefficients,
electrical conductivity,
Khuzestan plain and total dissolved solids.

##### 142 Solubility of Organics in Water and Silicon Oil: A Comparative Study

**Authors:**
Edison Muzenda

**Abstract:**

The aim of this study was to compare the solubility of selected volatile organic compounds in water and silicon oil using the simple static headspace method. The experimental design allowed equilibrium achievement within 30 – 60 minutes. Infinite dilution activity coefficients and Henry-s law constants for various organics representing esters, ketones, alkanes, aromatics, cycloalkanes and amines were measured at 303K. The measurements were reproducible with a relative standard deviation and coefficient of variation of 1.3x10-3 and 1.3 respectively. The static determined activity coefficients using shaker flasks were reasonably comparable to those obtained using the gas liquid - chromatographic technique and those predicted using the group contribution methods mainly the UNIFAC. Silicon oil chemically known as polydimethysiloxane was found to be better absorbent for VOCs than water which quickly becomes saturated. For example the infinite dilution mole fraction based activity coefficients of hexane is 0.503 and 277 000 in silicon oil and water respectively. Thus silicon oil gives a superior factor of 550 696. Henry-s law constants and activity coefficients at infinite dilution play a significant role in the design of scrubbers for abatement of volatile organic compounds from contaminated air streams. This paper presents the phase equilibrium of volatile organic compounds in very dilute aqueous and polymeric solutions indicating the movement and fate of chemical in air and solvent. The successful comparison of the results obtained here and those obtained using other methods by the same authors and in literature, means that the results obtained here are reliable.

**Keywords:**
Abatement,
absorbent,
activity coefficients,
equilibrium,
Henry's law constant.

##### 141 Computational Prediction of Complicated Atmospheric Motion for Spinning or non- Spinning Projectiles

**Authors:**
Dimitrios N. Gkritzapis,
Elias E. Panagiotopoulos,
Dionissios P. Margaris,
Dimitrios G. Papanikas

**Abstract:**

**Keywords:**
Constant-Variable aerodynamic coefficients,
low and high pitch angles,
wind.

##### 140 Physical Parameter Based Compact Expression for Propagation Constant of SWCNT Interconnects

**Authors:**
Kollarama Subramanyam,
Nisha Kuruvilla,
J. P. Raina

**Abstract:**

Novel compact expressions for propagation constant (γ) of SWCNT and bundled SWCNTs interconnect, in terms of physical parameters such as length, operating frequency and diameter of CNTs is proposed in this work. These simplified expressions enable physical insight and accurate estimation of signal attenuation level and its phase change at any length for a particular frequency. The proposed expressions are validated against SPICE simulated results of lumped as well as distributed equivalent electrical RLC nets of CNT interconnect. These expressions also help us to evaluate the cut off frequencies of SWCNTs for different interconnect lengths.

**Keywords:**
Attenuation constant,
Bundled SWCNT,
CNT interconnects,
Propagation Constant.

##### 139 A Simplified Approach for Load Flow Analysis of Radial Distribution Network

**Authors:**
K. Vinoth Kumar,
M.P. Selvan

**Abstract:**

**Keywords:**
constant current load,
constant impedance load,
constant power load,
forward–backward sweep,
load flow
analysis,
radial distribution system.

##### 138 Design and Development of Constant Stress Composite Cantilever Beam

**Authors:**
Vinod B. Suryawanshi,
Ajit D. Kelkar

**Abstract:**

Composite materials, due to their unique properties such as high strength to weight ratio, corrosion resistance, and impact resistance have huge potential as structural materials in automotive, construction and transportation applications. However, these properties often come at higher cost owing to complex design methods, difficult manufacturing processes and raw material cost. Traditionally, tapered laminated composite structures are manufactured using autoclave manufacturing process by ply drop off technique. Autoclave manufacturing though very powerful suffers from high capital investment and higher energy consumption. As per the current trends in composite manufacturing, Out of Autoclave (OoA) processes are looked as emerging technologies for manufacturing the structural composite components for aerospace and defense applications. However, there is a need for improvement among these processes to make them reliable and consistent. In this paper, feasibility of using out of autoclave process to manufacture the variable thickness cantilever beam is discussed. The minimum weight design for the composite beam is obtained using constant stress beam concept by tailoring the thickness of the beam. Ply drop off techniques was used to fabricate the variable thickness beam from glass/epoxy prepregs. Experiments were conducted to measure bending stresses along the span of the cantilever beam at different intervals by applying the concentrated load at the free end. Experimental results showed that the stresses in the bean at different intervals were constant. This proves the ability of OoA process to manufacture the constant stress beam. Finite element model for the constant stress beam was developed using commercial finite element simulation software. It was observed that the simulation results agreed very well with the experimental results and thus validated design and manufacturing approach used.

**Keywords:**
Beams,
Composites,
Constant Stress,
Structures.

##### 137 Analysis of Distribution of Thrust, Torque and Efficiency of a Constant Chord, Constant Pitch C.R.P. Fan by H.E.S. Method

**Authors:**
Morteza Abbaszadeh,
Parvin Nikpoorparizi,
Mina Shahrooz

**Abstract:**

**Keywords:**
C.F.D Test,
Counter Rotating Propeller,
H.E.S. Method,
R.S.M. Method

##### 136 Computation of Probability Coefficients using Binary Decision Diagram and their Application in Test Vector Generation

**Authors:**
Ashutosh Kumar Singh,
Anand Mohan

**Abstract:**

**Keywords:**
Binary Decision Diagrams,
Spectral Coefficients,
Fault detection

##### 135 Computing Center Conditions for Non-analytic Vector Fields with Constant Angular Speed

**Authors:**
Li Feng

**Abstract:**

We investigate the planar quasi-septic non-analytic systems which have a center-focus equilibrium at the origin and whose angular speed is constant. The system could be changed into an analytic system by two transformations, with the help of computer algebra system MATHEMATICA, the conditions of uniform isochronous center are obtained.

**Keywords:**
Non-analytic,
center–focus problem,
Lyapunov constant,
uniform isochronous center.

##### 134 Comparison of MFCC and Cepstral Coefficients as a Feature Set for PCG Biometric Systems

**Authors:**
Justin Leo Cheang Loong,
Khazaimatol S Subari,
Muhammad Kamil Abdullah,
Nurul Nadia Ahmad,
RosliBesar

**Abstract:**

**Keywords:**
Biometric,
Phonocardiogram,
Cepstral Coefficients,
Mel Frequency

##### 133 Modeling and Simulation of a Serial Production Line with Constant Work-In-Process

**Authors:**
Mehmet Savsar

**Abstract:**

**Keywords:**
Production line simulator,
Push-pull system,
JIT
system,
Constant WIP,
Machine failures.

##### 132 Effects of Video Games and Online Chat on Mathematics Performance in High School: An Approach of Multivariate Data Analysis

**Authors:**
Lina Wu,
Wenyi Lu,
Ye Li

**Abstract:**

Regarding heavy video game players for boys and super online chat lovers for girls as a symbolic phrase in the current adolescent culture, this project of data analysis verifies the displacement effect on deteriorating mathematics performance. To evaluate correlation or regression coefficients between a factor of playing video games or chatting online and mathematics performance compared with other factors, we use multivariate analysis technique and take gender difference into account. We find the most important reason for the negative sign of the displacement effect on mathematics performance due to students’ poor academic background. Statistical analysis methods in this project could be applied to study internet users’ academic performance from the high school education to the college education.

**Keywords:**
Correlation coefficients,
displacement effect,
gender difference,
multivariate analysis technique,
regression coefficients.

##### 131 Effect of Assumptions of Normal Shock Location on the Design of Supersonic Ejectors for Refrigeration

**Authors:**
Payam Haghparast,
Mikhail V. Sorin,
Hakim Nesreddine

**Abstract:**

The complex oblique shock phenomenon can be simply assumed as a normal shock at the constant area section to simulate a sharp pressure increase and velocity decrease in 1-D thermodynamic models. The assumed normal shock location is one of the greatest sources of error in ejector thermodynamic models. Most researchers consider an arbitrary location without justifying it. Our study compares the effect of normal shock place on ejector dimensions in 1-D models. To this aim, two different ejector experimental test benches, a constant area-mixing ejector (CAM) and a constant pressure-mixing (CPM) are considered, with different known geometries, operating conditions and working fluids (R245fa, R141b). In the first step, in order to evaluate the real value of the efficiencies in the different ejector parts and critical back pressure, a CFD model was built and validated by experimental data for two types of ejectors. These reference data are then used as input to the 1D model to calculate the lengths and the diameters of the ejectors. Afterwards, the design output geometry calculated by the 1D model is compared directly with the corresponding experimental geometry. It was found that there is a good agreement between the ejector dimensions obtained by the 1D model, for both CAM and CPM, with experimental ejector data. Furthermore, it is shown that normal shock place affects only the constant area length as it is proven that the inlet normal shock assumption results in more accurate length. Taking into account previous 1D models, the results suggest the use of the assumed normal shock location at the inlet of the constant area duct to design the supersonic ejectors.

**Keywords:**
1D model,
constant area-mixing,
constant pressure-mixing,
normal shock location,
ejector dimensions.

##### 130 Pulse Generator with Constant Pulse Width

**Authors:**
Hanif Che Lah,
Wee Leong Son,
Rozita Borhan

**Abstract:**

This paper is about method to produce a stable and accurate constant output pulse width regardless of the amplitude, period and pulse width variation of the input signal source. The pulse generated is usually being used in numerous applications as the reference input source to other circuits in the system. Therefore, it is crucial to produce a clean and constant pulse width to make sure the system is working accurately as expected.

**Keywords:**
Amplitude,
Constant Pulse Width,
Frequency
Divider,
Pulse Generator.

##### 129 The Capacity of Mel Frequency Cepstral Coefficients for Speech Recognition

**Authors:**
Fawaz S. Al-Anzi,
Dia AbuZeina

**Abstract:**

Speech recognition is of an important contribution in promoting new technologies in human computer interaction. Today, there is a growing need to employ speech technology in daily life and business activities. However, speech recognition is a challenging task that requires different stages before obtaining the desired output. Among automatic speech recognition (ASR) components is the feature extraction process, which parameterizes the speech signal to produce the corresponding feature vectors. Feature extraction process aims at approximating the linguistic content that is conveyed by the input speech signal. In speech processing field, there are several methods to extract speech features, however, Mel Frequency Cepstral Coefficients (MFCC) is the popular technique. It has been long observed that the MFCC is dominantly used in the well-known recognizers such as the Carnegie Mellon University (CMU) Sphinx and the Markov Model Toolkit (HTK). Hence, this paper focuses on the MFCC method as the standard choice to identify the different speech segments in order to obtain the language phonemes for further training and decoding steps. Due to MFCC good performance, the previous studies show that the MFCC dominates the Arabic ASR research. In this paper, we demonstrate MFCC as well as the intermediate steps that are performed to get these coefficients using the HTK toolkit.

**Keywords:**
Speech recognition,
acoustic features,
Mel Frequency Cepstral Coefficients.

##### 128 Design of a Constant Chord Single-Rotating Propeller using Lock and Goldstein Techniques

**Authors:**
Samrand Rashahmadi,
Morteza Abbaszadeh,
Sana Hoseyni,
Raziyeh Alizadeh

**Abstract:**

**Keywords:**
Single rotating propeller,
Design,
C.F.D. test,
constant chord

##### 127 Comparing Autoregressive Moving Average (ARMA) Coefficients Determination using Artificial Neural Networks with Other Techniques

**Authors:**
Abiodun M. Aibinu,
Momoh J. E. Salami,
Amir A. Shafie,
Athaur Rahman Najeeb

**Abstract:**

Autoregressive Moving average (ARMA) is a parametric based method of signal representation. It is suitable for problems in which the signal can be modeled by explicit known source functions with a few adjustable parameters. Various methods have been suggested for the coefficients determination among which are Prony, Pade, Autocorrelation, Covariance and most recently, the use of Artificial Neural Network technique. In this paper, the method of using Artificial Neural network (ANN) technique is compared with some known and widely acceptable techniques. The comparisons is entirely based on the value of the coefficients obtained. Result obtained shows that the use of ANN also gives accurate in computing the coefficients of an ARMA system.

**Keywords:**
Autoregressive moving average,
coefficients,
back propagation,
model parameters,
neural network,
weight.

##### 126 Determination of Unsaturated Soil Permeability Based on Geometric Factor Development of Constant Discharge Model

**Authors:**
A. Rifa’i,
Y. Takeshita,
M. Komatsu

**Abstract:**

*k*) in both saturated and unsaturated conditions to solve this problem. More accurate and efficient field testing procedure is required to obtain permeability data that present the field condition. One of the field permeability test equipment is Constant Discharge procedure to determine the permeability coefficient. Necessary adjustments of the Constant Discharge procedure are needed to be determined especially the value of geometric factor (

*F*) to improve the corresponding value of permeability coefficient. The value of

*k*will be correlated with the value of volumetric water content (

*θ*) of an unsaturated condition until saturated condition. The principle procedure of Constant Discharge model provides a constant flow in permeameter tube that flows into the ground until the water level in the tube becomes constant. Constant water level in the tube is highly dependent on the tube dimension. Every tube dimension has a shape factor called the geometric factor that affects the result of the test. Geometric factor value is defined as the characteristic of shape and radius of the tube. This research has modified the geometric factor parameters by using empty material tube method so that the geometric factor will change. Saturation level is monitored by using soil moisture sensor. The field test results were compared with the results of laboratory tests to validate the results of the test. Field and laboratory test results of empty tube material method have an average difference of 3.33 x 10

^{-4}cm/sec. The test results showed that modified geometric factor provides more accurate data. The improved methods of constant discharge procedure provide more relevant results.

**Keywords:**
Constant discharge,
geometric factor,
permeability coefficient,
unsaturated soils.

##### 125 Improvement Approach on Rotor Time Constant Adaptation with Optimum Flux in IFOC for Induction Machines Drives

**Authors:**
S. Grouni,
R. Ibtiouen,
M. Kidouche,
O. Touhami

**Abstract:**

**Keywords:**
Indirect Field Oriented Control (IFOC),
InductionMachine (IM),
Rotor Time Constant,
Parameters ApproachAdaptation. Optimum rotor flux.

##### 124 Development of In Situ Permeability Test Using Constant Discharge Method for Sandy Soils

**Authors:**
A. Rifa’i,
Y. Takeshita,
M. Komatsu

**Abstract:**

The post-rain puddles problem that occurs in the first yard of Prambanan Temple are often disturbing visitor activity. A poodle layer and a drainage system had ever built to avoid such a problem, but puddles still did not stop appearing after rain. Permeability parameter needs to be determined by using a simpler procedure to find exact method of solution. The instrument modelling was proposed according to the development of field permeability testing instrument. This experiment used a proposed Constant Discharge method. Constant Discharge method used a tube poured with constant water flow from unsaturated until saturated soil condition. Volumetric water content (θ) were monitored by soil moisture measurement device. The results were correlations between k and θ which were drawn by numerical approach from Van Genutchen model. Parameters θr optimum value obtained from the test was at very dry soil. Coefficient of permeability with a density of 19.8 kN/m3 for unsaturated conditions was in range of 3 x 10-6 cm/sec (Sr=68%) until 9.98 x 10-4 cm/sec (Sr=82%). The equipment and testing procedure developed in this research was quite effective, simple and easy to be implemented on determining field soil permeability coefficient value of sandy soil. Using constant discharge method in proposed permeability test, value of permeability coefficient under unsaturated condition can be obtained without establish soil water characteristic curve.

**Keywords:**
Constant discharge method,
in situ permeability test,
sandy soil,
unsaturated conditions.

##### 123 Selection of Rayleigh Damping Coefficients for Seismic Response Analysis of Soil Layers

**Authors:**
Huai-Feng Wang,
Meng-Lin Lou,
Ru-Lin Zhang

**Abstract:**

**Keywords:**
Rayleigh damping,
modal damping,
damping coefficients,
seismic response analysis.

##### 122 Heat Transfer Coefficients for Particulate Airflow in Shell and Coiled Tube Heat Exchangers

**Authors:**
W. Witchayanuwat,
S. Kheawhom

**Abstract:**

**Keywords:**
Shell and coiled tube heat exchanger,
Spray drying
tower,
Heat transfer coefficients.

##### 121 Prediction of Henry's Constant in Polymer Solutions using the Peng-Robinson Equation of State

**Authors:**
Somayeh Tourani,
Alireza Behvandi

**Abstract:**

The peng-Robinson (PR), a cubic equation of state (EoS), is extended to polymers by using a single set of energy (A1, A2, A3) and co-volume (b) parameters per polymer fitted to experimental volume data. Excellent results for the volumetric behavior of the 11 polymer up to 2000 bar pressure are obtained. The EoS is applied to the correlation and prediction of Henry constants in polymer solutions comprising three polymer and many nonpolar and polar solvents, including supercritical gases. The correlation achieved with two adjustable parameter is satisfactory compared with the experimental data. As a result, the present work provides a simple and useful model for the prediction of Henry's constant for polymer containing systems including those containing polar, nonpolar and supercritical fluids.

**Keywords:**
Equation of state,
Henry's constant,
Peng-Robinson,
polymer solution.

##### 120 Evaluation of Stiffness and Damping Coefficients of Multiple Axial Groove Water Lubricated Bearing Using Computational Fluid Dynamics

**Authors:**
Neville Fernandes,
Satish Shenoy B.,
Raghuvir Pai B.,
Rammohan S. Pai B,
Shrikanth Rao.D

**Abstract:**

This research details a Computational Fluid Dynamics (CFD) approach to model fluid flow in a journal bearing with 8 equispaced semi-circular axial grooves. Water is used as the lubricant and is fed from one end of the bearing to the other, under pressure. The geometry of the bearing is modeled using a commercially available modeling software GAMBIT and the flow analysis is performed using a dedicated CFD analysis software FLUENT. The pressure distribution in the bearing clearance is obtained from FLUENT for various whirl ratios and is used to calculate the hydrodynamic force components in the radial and tangential direction of the bearing. These values along with the various whirl speeds can be used to do a regression analysis to determine the stiffness and damping coefficients. The values obtained are then compared with the stiffness and damping coefficients of a 3 Axial groove water lubricated journal bearing and those obtained from a FORTRAN code for a similar bearing.

**Keywords:**
CFD,
multiple axial groove,
Water lubricated,
Stiffness and Damping Coefficients.

##### 119 Speech Enhancement Using Wavelet Coefficients Masking with Local Binary Patterns

**Authors:**
Christian Arcos,
Marley Vellasco,
Abraham Alcaim

**Abstract:**

**Keywords:**
Binary labels,
local binary patterns,
mask,
wavelet
coefficients,
speech enhancement,
speech recognition.

##### 118 Effect of Prandtl Number on Natural Convection Heat Transfer from a Heated Semi-Circular Cylinder

**Authors:**
Avinash Chandra,
R. P. Chhabra

**Abstract:**

**Keywords:**
Constant heat flux,
Constant surface temperature,
Grashof number,
natural convection,
Prandtl number,
Semi-circular
cylinder

##### 117 Medical Image Watermark and Tamper Detection Using Constant Correlation Spread Spectrum Watermarking

**Authors:**
Peter U. Eze,
P. Udaya,
Robin J. Evans

**Abstract:**

Data hiding can be achieved by Steganography or invisible digital watermarking. For digital watermarking, both accurate retrieval of the embedded watermark and the integrity of the cover image are important. Medical image security in Teleradiology is one of the applications where the embedded patient record needs to be extracted with accuracy as well as the medical image integrity verified. In this research paper, the Constant Correlation Spread Spectrum digital watermarking for medical image tamper detection and accurate embedded watermark retrieval is introduced. In the proposed method, a watermark bit from a patient record is spread in a medical image sub-block such that the correlation of all watermarked sub-blocks with a spreading code, W, would have a constant value, *p.* The constant correlation *p*, spreading code, W and the size of the sub-blocks constitute the secret key. Tamper detection is achieved by flagging any sub-block whose correlation value deviates by more than a small value, ℇ, from *p*. The major features of our new scheme include: (1) Improving watermark detection accuracy for high-pixel depth medical images by reducing the Bit Error Rate (BER) to Zero and (2) block-level tamper detection in a single computational process with simultaneous watermark detection, thereby increasing utility with the same computational cost.

**Keywords:**
Constant correlation,
medical image,
spread spectrum,
tamper detection,
watermarking.

##### 116 Constructive Proof of Tychonoff’s Fixed Point Theorem for Sequentially Locally Non-Constant Functions

**Authors:**
Yasuhito Tanaka

**Abstract:**

We present a constructive proof of Tychonoff’s fixed point theorem in a locally convex space for uniformly continuous and sequentially locally non-constant functions.

**Keywords:**
sequentially locally non-constant functions,
Tychonoff’s
fixed point theorem,
constructive mathematics.

##### 115 Constructive Proof of the Existence of an Equilibrium in a Competitive Economy with Sequentially Locally Non-Constant Excess Demand Functions

**Authors:**
Yasuhito Tanaka

**Abstract:**

**Keywords:**
Sequentially locally non-constant excess demand functions,
Equilibrium in a competitive economy,
Constructive mathematics

##### 114 Design of an Stable GPC for Nonminimum Phase LTI Systems

**Authors:**
Mahdi Yaghobi,
Mohammad Haeri

**Abstract:**

**Keywords:**
GPC,
Stability,
Varying Weighting Coefficients.