**Commenced**in January 2007

**Frequency:**Monthly

**Edition:**International

**Paper Count:**194

# Search results for: Hall coefficient

##### 194 The Hall Coefficient and Magnetoresistance in Rectangular Quantum Wires with Infinitely High Potential under the Influence of a Laser Radiation

**Authors:**
Nguyen Thu Huong,
Nguyen Quang Bau

**Abstract:**

**Keywords:**
Hall coefficient,
rectangular quantum wires,
electron-optical phonon interaction,
quantum kinetic equation.

##### 193 Hall Coefficient in the Presence of Strong Electromagnetic Waves Caused by Confined Electrons and Phonons in a Rectangular Quantum Wire

**Authors:**
Nguyen Quang Bau,
Nguyen Thu Huong,
Dang Thi Thanh Thuy

**Abstract:**

**Keywords:**
Hall coefficient,
rectangular quantum wires,
electron-optical phonon interaction,
quantum kinetic equation,
confined phonons.

##### 192 Thailand Throne Hall Architecture in the Grand Palace in the Early Days of Ratthanakosin Era

**Authors:**
Somchai Seviset,
Lin Jian Qun

**Abstract:**

**Keywords:**
Amarindra-vinitchai-mahaisuraya Bhiman throne
hall,
throne hall architecture,
grand palace,
Thai traditional
architecture,
Ratthanakosin era

##### 191 Experimental Investigation of Adjacent Hall Structures Parameters

**Authors:**
Ivelina N. Cholakova,
Tihomir B. Takov,
Radostin Ts. Tsankov,
Nicolas Simonne,
Slavka S. Tzanova

**Abstract:**

**Keywords:**
Adjacent Hall sensors,
offset compensation,
voltage related sensitivity,
0.18μm CMOS technology.

##### 190 Lookup Table Reduction and Its Error Analysis of Hall Sensor-Based Rotation Angle Measurement

**Authors:**
Young-San Shin,
Seongsoo Lee

**Abstract:**

Hall sensor is widely used to measure rotation angle. When the Hall voltage is measured for linear displacement, it is converted to angular displacement using arctangent function, which requires a large lookup table. In this paper, a lookup table reduction technique is presented for angle measurement. When the input of the lookup table is small within a certain threshold, the change of the outputs with respect to the change of the inputs is relatively small. Thus, several inputs can share same output, which significantly reduce the lookup table size. Its error analysis was also performed, and the threshold was determined so as to maintain the error less than 1°. When the Hall voltage has 11-bit resolution, the lookup table size is reduced from 1,024 samples to 279 samples.

**Keywords:**
Hall sensor,
angle measurement,
lookup table,
arctangent.

##### 189 Applications of AUSM+ Scheme on Subsonic, Supersonic and Hypersonic Flows Fields

**Authors:**
Muhammad Yamin Younis,
Muhammad Amjad Sohail,
Tawfiqur Rahman,
Zaka Muhammad,
Saifur Rahman Bakaul

**Abstract:**

**Keywords:**
Subsonic,
supersonic,
Hypersonic,
AUSM+,
Drag
Coefficient,
lift Coefficient,
Pitching moment coefficient,
pressure
Coefficient,
turbulent flow.

##### 188 A Study on the Determinants of Earnings Response Coefficient in an Emerging Market

**Authors:**
Bita Mashayekhi,
Zeynab Lotfi Aghel

**Abstract:**

**Keywords:**
Earnings response coefficient,
return response coefficient,
firm size,
earnings growth,
earnings persistence.

##### 187 Calculation Analysis of an Axial Compressor Supersonic Stage Impeller

**Authors:**
Y. B. Galerkin,
E. Y. Popova,
K. V. Soldatova

**Abstract:**

There is an evident trend to elevate pressure ratio of a single stage of a turbo compressors - axial compressors in particular. Whilst there was an opinion recently that a pressure ratio 1,9 was a reasonable limit, later appeared information on successful modeling tested of stages with pressure ratio up to 2,8. The authors recon that lack of information on high pressure stages makes actual a study of rational choice of design parameters before high supersonic flow problems solving. The computer program of an engineering type was developed. Below is presented a sample of its application to study possible parameters of the impeller of the stage with pressure ratio 3,0. Influence of two main design parameters on expected efficiency, periphery blade speed and flow structure is demonstrated. The results had lead to choose a variant for further analysis and improvement by CFD methods.

**Keywords:**
Supersonic stage,
impeller,
efficiency,
flow rate
coefficient,
work coefficient,
loss coefficient,
oblique shock,
direct
shock.

##### 186 Experimental and Semi-Analytical Investigation of Wave Interaction with Double Vertical Slotted Walls

**Authors:**
H. Ahmed,
A. Schlenkhoff,
R. Rousta,
R. Abdelaziz

**Abstract:**

Vertical slotted walls can be used as permeable breakwaters to provide economical and environmental protection from undesirable waves and currents inside the port. The permeable breakwaters are partially protection and have been suggested to overcome the environmental disadvantages of fully protection breakwaters. For regular waves a semi-analytical model is based on an eigenfunction expansion method and utilizes a boundary condition at the surface of each wall are developed to detect the energy dissipation through the slots. Extensive laboratory tests are carried out to validate the semi-analytic models. The structure of the physical model contains two walls and it consists of impermeable upper and lower part, where the draft is based a decimal multiple of the total depth. The middle part is permeable with a porosity of 50%. The second barrier is located at a distant of 0.5, 1, 1.5 and 2 times of the water depth from the first one. A comparison of the theoretical results with previous studies and experimental measurements of the present study show a good agreement and that, the semi-analytical model is able to adequately reproduce most the important features of the experiment.

**Keywords:**
Permeable breakwater,
double vertical slotted walls,
semi-analytical model,
transmission coefficient,
reflection
coefficient,
energy dissipation coefficient.

##### 185 On the Hierarchical Ergodicity Coefficient

**Authors:**
Yilun Shang

**Abstract:**

In this paper, we deal with the fundamental concepts and properties of ergodicity coefficients in a hierarchical sense by making use of partition. Moreover, we establish a hierarchial Hajnal’s inequality improving some previous results.

**Keywords:**
Stochastic matrix,
ergodicity coefficient,
partition.

##### 184 A New Algorithm for Determining the Leading Coefficient of in the Parabolic Equation

**Authors:**
Shiping Zhou,
Minggen Cui

**Abstract:**

**Keywords:**
parabolic equations,
coefficient inverse problem,
reproducing
kernel.

##### 183 Confidence Intervals for the Normal Mean with Known Coefficient of Variation

**Authors:**
Suparat Niwitpong

**Abstract:**

In this paper we proposed two new confidence intervals for the normal population mean with known coefficient of variation. This situation occurs normally in environment and agriculture experiments where the scientist knows the coefficient of variation of their experiments. We propose two new confidence intervals for this problem based on the recent work of Searls [5] and the new method proposed in this paper for the first time. We derive analytic expressions for the coverage probability and the expected length of each confidence interval. Monte Carlo simulation will be used to assess the performance of these intervals based on their expected lengths.

**Keywords:**
confidence interval,
coverage probability,
expected length,
known coefficient of variation.

##### 182 Approximations to the Distribution of the Sample Correlation Coefficient

**Authors:**
John N. Haddad,
Serge B. Provost

**Abstract:**

**Keywords:**
Sample correlation coefficient,
density approximation,
confidence intervals.

##### 181 Effect of Composition on Work Hardening Coefficient of Bismuth-Lead Binary Alloy

**Authors:**
K. A. Mistry,
I. B. Patel,
A. H. Prajapati

**Abstract:**

In the present work, the alloy of Bismuth-lead is prepared on the basis of percentage of molecular weight 9:1, 5:5 and 1:9 ratios and grown by Zone- Refining Technique under a vacuum atmosphere. The EDAX of these samples are done and the results are reported. Micro hardness test has been used as an alternative test for measuring material’s tensile properties. The effect of temperature and load on the hardness of the grown alloy has been studied. Further the comparative studies of work hardening coefficients are reported.

**Keywords:**
EDAX,
hardening coefficient,
Micro hardness,
Bi-Pb
alloy.

##### 180 Modern State of the Universal Modeling for Centrifugal Compressors

**Authors:**
Y. Galerkin,
K. Soldatova,
A. Drozdov

**Abstract:**

The 6th version of Universal modeling method for centrifugal compressor stage calculation is described. Identification of the new mathematical model was made. As a result of identification the uniform set of empirical coefficients is received. The efficiency definition error is 0,86 % at a design point. The efficiency definition error at five flow rate points (except a point of the maximum flow rate) is 1,22 %. Several variants of the stage with 3D impellers designed by 6th version program and quasi threedimensional calculation programs were compared by their gas dynamic performances CFD (NUMECA FINE TURBO). Performance comparison demonstrated general principles of design validity and leads to some design recommendations.

**Keywords:**
Compressor design,
loss model,
performance
prediction,
test data,
model stages,
flow rate coefficient,
work
coefficient.

##### 179 Generalization of Clustering Coefficient on Lattice Networks Applied to Criminal Networks

**Authors:**
Christian H. Sanabria-Montaña,
Rodrigo Huerta-Quintanilla

**Abstract:**

**Keywords:**
Clustering coefficient,
criminology,
generalized,
regular network d-dimensional.

##### 178 Coefficient of Parentage for Crop Hybridization

**Authors:**
Manpreet Singh,
Parvinder Singh Sandhu,
Basant Raj Singh

**Abstract:**

**Keywords:**
Coefficient of Parentage,
Morphological characters,
Pedigree,
Genetic Diversity.

##### 177 Bending Gradient Coefficient Correction for I-Beams

**Authors:**
H. R. Kazemi Nia,
A. Yeganeh Fallah

**Abstract:**

**Keywords:**
Beams critical moment,
Bending Gradient Coefficient,
finite element,
Lateral Torsional Buckling

##### 176 On Simple Confidence Intervals for the Normal Mean with Known Coefficient of Variation

**Authors:**
Suparat Niwitpong,
Sa-aat Niwitpong

**Abstract:**

In this paper we proposed the new confidence interval for the normal population mean with known coefficient of variation. In practice, this situation occurs normally in environment and agriculture sciences where we know the standard deviation is proportional to the mean. As a result, the coefficient of variation of is known. We propose the new confidence interval based on the recent work of Khan [3] and this new confidence interval will compare with our previous work, see, e.g. Niwitpong [5]. We derive analytic expressions for the coverage probability and the expected length of each confidence interval. A numerical method will be used to assess the performance of these intervals based on their expected lengths.

**Keywords:**
confidence interval,
coverage probability,
expected length,
known coefficient of variation.

##### 175 A Communication Signal Recognition Algorithm Based on Holder Coefficient Characteristics

**Authors:**
Hui Zhang,
Ye Tian,
Fang Ye,
Ziming Guo

**Abstract:**

**Keywords:**
Communication signal,
feature extraction,
holder
coefficient,
improved cloud model.

##### 174 A Study of the Change of Damping Coefficient Regarding Minimum Displacement

**Authors:**
Tawiwat V.,
Narongkorn D.,
Auttapoom L.

**Abstract:**

This research proposes the change of damping coefficient regarding minimum displacement. From the mass with external forced and damper problem, when is the constant external forced transmitted to the understructure in the difference angle between 30 and 60 degrees. This force generates the vibration as general known; however, the objective of this problem is to have minimum displacement. As the angle is changed and the goal is the same; therefore, the damper of the system must be varied while keeping constant spring stiffness. The problem is solved by using nonlinear programming and the suitable changing of the damping coefficient is provided.

**Keywords:**
Damping coefficient,
Optimal control,
Minimum Displacement and Vibration

##### 173 Moderation in Temperature Dependence on Counter Frictional Coefficient and Prevention of Wear of C/C Composites by Synthesizing SiC around Surface and Internal Vacancies

**Authors:**
Noboru Wakamoto,
Kiyotaka Obunai,
Kazuya Okubo,
Toru Fujii

**Abstract:**

The aim of this study is to moderate the dependence of counter frictional coefficient on temperature between counter surfaces and to reduce the wear of C/C composites at low temperature. To modify the C/C composites, Silica (SiO_{2}) powders were added into phenolic resin for carbon precursor. The preform plate of the precursor of C/C composites was prepared by conventional filament winding method. The C/C composites plates were obtained by carbonizing preform plate at 2200 °C under an argon atmosphere. At that time, the silicon carbides (SiC) were synthesized around the surfaces and the internal vacancies of the C/C composites. The frictional coefficient on the counter surfaces and specific wear volumes of the C/C composites were measured by our developed frictional test machine like pin-on disk type. The XRD indicated that SiC was synthesized in the body of C/C composite fabricated by current method. The results of friction test showed that coefficient of friction of unmodified C/C composites have temperature dependence when the test condition was changed. In contrast, frictional coefficient of the C/C composite modified with SiO_{2 }powders was almost constant at about 0.27 when the temperature condition was changed from Room Temperature (RT) to 300 °C. The specific wear rate decreased from 25×10^{-6} mm^{2}/N to 0.1×10^{-6} mm^{2}/N. The observations of the surfaces after friction tests showed that the frictional surface of the modified C/C composites was covered with a film produced by the friction. This study found that synthesizing SiC around surface and internal vacancies of C/C composites was effective to moderate the dependence on the frictional coefficient and reduce to the abrasion of C/C composites.

**Keywords:**
C/C composites,
frictional coefficient,
SiC,
wear.

##### 172 Mathematical Models for Overall Gas Transfer Coefficient Using Different Theories and Evaluating Their Measurement Accuracy

**Authors:**
Shashank.B. Thakre,
Lalit.B. Bhuyar,
Samir.J. Deshmukh

**Abstract:**

**Keywords:**
Theories,
Dissolved oxygen,
Mathematical model,
Gas Transfer coefficient,
Accuracy.

##### 171 The Effect of Discontinued Water Spray Cooling on the Heat Transfer Coefficient

**Authors:**
J. Hrabovský,
M. Chabičovský,
J. Horský

**Abstract:**

Water spray cooling is a technique typically used in heat treatment and other metallurgical processes where controlled temperature regimes are required. Water spray cooling is used in static (without movement) or dynamic (with movement of the steel plate) regimes. The static regime is notable for the fixed position of the hot steel plate and fixed spray nozzle. This regime is typical for quenching systems focused on heat treatment of the steel plate. The second application of spray cooling is the dynamic regime. The dynamic regime is notable for its static section cooling system and moving steel plate. This regime is used in rolling and finishing mills. The fixed position of cooling sections with nozzles and the movement of the steel plate produce nonhomogeneous water distribution on the steel plate. The length of cooling sections and placement of water nozzles in combination with the nonhomogeneity of water distribution lead to discontinued or interrupted cooling conditions. The impact of static and dynamic regimes on cooling intensity and the heat transfer coefficient during the cooling process of steel plates is an important issue. Heat treatment of steel is accompanied by oxide scale growth. The oxide scale layers can significantly modify the cooling properties and intensity during the cooling. The combination of static and dynamic (section) regimes with the variable thickness of the oxide scale layer on the steel surface impact the final cooling intensity. The study of the influence of the oxide scale layers with different cooling regimes was carried out using experimental measurements and numerical analysis. The experimental measurements compared both types of cooling regimes and the cooling of scale-free surfaces and oxidized surfaces. A numerical analysis was prepared to simulate the cooling process with different conditions of the section and samples with different oxide scale layers.

**Keywords:**
Heat transfer coefficient,
numerical analysis,
oxide
layer,
spray cooling.

##### 170 The Prediction of Sound Absorbing Coefficient for Multi-Layer Non-Woven

**Authors:**
Un-Hwan Park,
Jun-Hyeok Heo,
In-Sung Lee,
Tae-Hyeon Oh,
Dae-Gyu Park

**Abstract:**

**Keywords:**
Multi-layer nonwoven,
sound absorption coefficient,
scaled reverberation chamber,
impedance tubes.

##### 169 Development of Mathematical Model for Overall Oxygen Transfer Coefficient of an Aerator and Comparison with CFD Modeling

**Authors:**
Shashank.B. Thakre,
L.B. Bhuyar,
Samir.J. Deshmukh

**Abstract:**

**Keywords:**
CFD Model,
Overall oxygen transfer coefficient,
Power,
Mathematical Model,
Validation.

##### 168 Effect of Modeling of Hydraulic Form Loss Coefficient to Break on Emergency Core Coolant Bypass

**Authors:**
Young S. Bang,
Dong H. Yoon,
Seung H. Yoo

**Abstract:**

Emergency Core Coolant Bypass (ECC Bypass) has been regarded as an important phenomenon to peak cladding temperature of large-break loss-of-coolant-accidents (LBLOCA) in nuclear power plants (NPP). A modeling scheme to address the ECC Bypass phenomena and the calculation of LBLOCA using that scheme are discussed in the present paper. A hydraulic form loss coefficient (HFLC) from the reactor vessel downcomer to the broken cold leg is predicted by the computational fluid dynamics (CFD) code with a variation of the void fraction incoming from the downcomer. The maximum, mean, and minimum values of FLC are derived from the CFD results and are incorporated into the LBLOCA calculation using a system thermal-hydraulic code, MARS-KS. As a relevant parameter addressing the ECC Bypass phenomena, the FLC to the break and its range are proposed.

**Keywords:**
CFD analysis,
ECC Bypass,
hydraulic form loss coefficient,
system thermal-hydraulic code.

##### 167 On Quasi Conformally Flat LP-Sasakian Manifolds with a Coefficient α

**Authors:**
Jay Prakash Singh

**Abstract:**

**Keywords:**
LP-Sasakian manifolds,
coefficient α,
quasi conformal
curvature tensor,
concircular vector field,
torse forming vector field,
η-Einstein manifold.

##### 166 Experimental Study of Open Water Non-Series Marine Propeller Performance

**Authors:**
M. A. Elghorab,
A. Abou El-Azm Aly,
A. S. Elwetedy,
M. A. Kotb

**Abstract:**

**Keywords:**
Advance speed,
marine propeller,
open water performance,
thrust coefficient,
torque coefficient.

##### 165 Preparing the Curve Number (CN) and Surface Runoff Coefficient (C) Map of the Basin in the Aghche Watershed, Iran

**Authors:**
Ali Gholami,
Ebrahim Panahpour,
Amir Hossein Davami

**Abstract:**

**Keywords:**
Aghche Watershed,
Curve Numbers (CV),
Land UseChanges,
Surface Runoff Coefficient(C) Map,
W indicator