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Indian Journal of Engineering & Materials Sciences

 

 

 

 

ISSN : 0971-4588

 

CODEN : IEMSEW

VOLUME 11

NUMBER 5

OCTOBER 2004

  

 

CONTENTS

 

 

Engineering

 

 

 

Damage assessment of structures from changes in curvature damage factor using artificial neural network

 

369

Rashmi Ranjan Tripathy & Damodar Maity

 

[IPC Code: Int. Cl.7 G06N 3/06]

 

 

 

Effect of bluff body shape on vortex flow meter performance

378

B K Gandhi, S N Singh, V Seshadri & Jeeot Singh

 

[IPC Code: Int. Cl.7 F15D 1/00, B04C 7/00]

 

 

 

Numerical analysis of free surface flow around a ship in deep water

385

Md Shahjada Tarafder & Gazi Md Khalil

 

[IPC Code: Int. Cl.7 E02B 3/00]

 

 

 

Parametric analysis of combined turning and ball burnishing process

391

U M Shirsat & B B Ahujab

 

[IPC Code: Int. Cl.7 B23F 19/00, B23B 3/00]

 

 

 

Applications of new FGMOS based CCII in low voltage analog filters

397

Susheel Sharma, S S Rajput, L K Mangotra & S S Jamuar

 

[IPC Code: Int. Cl.7 H03H 15/02]

 

 

 

Evaluation of a conveyor belt material based on multi-criteria decision making

401

S Bhattacharya, B Sarkar & R N Mukherjee

 

[IPC Code: Int. Cl.7 B29D 29/06]

 

 

 

Effect of tyre overload and inflation pressure on rolling loss (resistance) and fuel consumption of automobile and truck/bus tyres

 

406

Padmanabha S Pillai

 

[IPC Code: Int. Cl.7 B60C 17/00, G01L 17/00]

 

 

 

Materials Science

 

 

 

Optical and dielectric properties of organic laser dye Rhodamine 6G doped silica xerogels with the variation of the sol-gel parameters

 

413

A Parvathy Rao & A Venkateswara Rao

 

[IPC Code: Int. Cl.7 C01B 33/16]

 

 

Theoretical approach to the tunneling mechanoluminescence produced during cleavage of II-VI semiconductors

 

421

Vibha Choudhary, Anubha Singh, V.K.Chandra, R.K.Gupta & B P Chandra

 

[IPC Code: Int. Cl.7 F21V 13/00, B28D 5/00]

 

 

 

Predicting detonation velocity of ideal and less ideal explosives via specific impulse

429

M H Keshavarz & H R Pouretedal

 

[IPC Code: Int. Cl.7 C06C ]

 

 

 

Mineral industries and their environmental aspects in Indian context

433

Mrinal K Ghose & Anjay Kumar

 

[IPC Code: Int. Cl.7 E21C ]

 

 

 

Effect of facet coatings on laser diode characteristics

438

P V Bhore, A P Shah, M R Gokhale, S Ghosh, A Bhattacharya & B M Arora

 

[IPC Code: Int. Cl.7 H01S 5/028]

 

 

 

 

Indian Journal of Engineering & Materials Sciences

 Vol. 11, October 2004, pp. 369-377

 

Damage assessment of structures from changes in curvature damage factor using artificial neural network

Rashmi Ranjan Tripathy & Damodar Maity

 

This paper presents a neural network based approach to detect and assess the structural damage. The basic strategy applied in this study is to train a neural network to recognize the behaviour of the undamaged structure as well as the structure with various possible damaged states. Curvature damage factor (CDF) is used as a possible candidate for the damage identification by error back-propagation training algorithm (EBPTA). When this trained network is subjected to the measured response, it should be able to detect any existing damage. This idea is applied on a cantilever beam and a plane frame. The results show the efficiency of the developed algorithm.

 

IPC Code: Int. Cl.7 G 06 N 3/06

 

 

 

Indian Journal of Engineering & Materials Sciences

 Vol. 11, October 2004, pp. 378-384

 

Effect of bluff body shape on vortex flow meter performance  

B K Gandhi, S N Singh, V Seshadri & Jeeot Singh

 

Frequency of shedding vortices in the wake of a bluff body is used to measure the flow rate in vortex flowmeters. A smooth bluff body shape may not generate stable vortices and needs sharp edges for the consistency of pulsed output. However, such bluff bodies give higher-pressure loss and drag force and therefore a need exists for optimising the body shape. In the present work, the flow over various body shapes in a pipe have been analysed using computational fluid dynamics to study the effect of body shape on pressure loss and drag coefficient. It is observed that the body shape with sharp corners have higher-pressure loss and drag compared to the cylindrical one. However, a triangular body shape with splitter plate or diamond shape has low coefficients of permanent pressure loss and drags compared to the other sharp cornered bodies and hence are better suited for use in the vortex flowmeters.

 

IPC Code: Int. Cl.7 F15D 1/00, B04C 7/00

 

 

 

Indian Journal of Engineering & Materials Sciences

 Vol. 11, October 2004, pp. 385-390

 

Numerical analysis of free surface flow around a ship in deep water

Md Shahjada Tarafder & Gazi Md Khalil

 

A boundary element method is presented for solving a non-linear free surface flow problem for a ship moving with a uniform speed in deep water. The free surface boundary condition is linearized by the systematic method of perturbation in terms of a small parameter. The surfaces are discretized into flat quadrilateral elements and the influence coefficients are calculated by Morino’s analytical formula. Dawson’s upstream finite difference operator is used in order to satisfy the radiation condition. The method of solution is based on the distribution of sources and dipoles on the body and the free surface, which will be obtained by a matrix solution. The matrix is solved by the L-U decomposition method. A verification of the numerical modelling is made using the Wigley hull and validity of the computer program is examined by comparing the details of wave profiles and wave-making resistance with the experimental result. The wave pattern consisting of transverse and diverging waves around ships in deep water is well predicted numerically.

 

IPC Code: Int. Cl.7 E 02 B 3/00

 

 

 

Indian Journal of Engineering & Materials Sciences

 Vol. 11, October 2004, pp. 391-396

 

Parametric analysis of combined turning and ball burnishing process  

U M Shirsat & B B Ahuja

 

Burnishing is a plastic deformation process, which is becoming more popular as a finishing process. Experimental work based on 23 factorial design has been carried out on Turn master T-40 lathe to establish the effect of the combined turning and two ball-burnishing parameters on the surface roughness and surface hardness of aluminum specimen. The results have been analyzed by the variance technique and the F-test, showing thereby that the lubricant, force, speed, and feed have significant effects on surface roughness and surface hardness. A pre-machined surface roughness of 0.63-0.75 mm (by turning) can be finished up to 0.11 mm (by burnishing) and improved micro hardness is obtained.

 

IPC Code: Int. Cl.7 B23F 19/00, B23B 3/00

  

 

 

Indian Journal of Engineering & Materials Sciences

 Vol. 11, October 2004, pp. 397-400

 

Applications of new FGMOS based CCII in low voltage analog filters

Susheel Sharma, S S Rajput, L K Mangotra & S S Jamuar

 

This paper aims at to develop floating gate MOSFET (FGMOS) based low voltage, voltage-mode and current-mode circuits operating at ± 0.75 V supply voltages. The utility of FGMOS for low voltage applications lies in its threshold voltage tunability. FGMOS based low voltage current mirror and its subsequent use in the development of second-generation current conveyor is presented which in turn has been used to realize low voltage all-pass and low-pass filters. The performance of these circuits has been verified by using PSpice simulations for 0.5 mm CMOS technology.

 

IPC Code: Int. Cl.7 H03H 15/02

 

 

 

Indian Journal of Engineering & Materials Sciences

Vol. 11, October 2004, pp. 401-405

 

Evaluation of a conveyor belt material based on multi-criteria decision making

S Bhattacharya, B Sarkar & R N Mukherjee

 

Conveyor belts are required to transport different types of materials in industries under varying operating conditions. A number of materials for such belts are available in the market. However, it is impossible to identify one such material, which will perfectly respond to all such requirements in a given environment. Hence arises the question of optimization. The present paper is based on one such optimization technique known as analytic hierarchy process (AHP). It considers a number of alternative materials as well as design criteria and arrives at the most suitable material. The algorithm calculates the priority vector (PV) values by eigen-vector method of pair-wise comparison. These PV values are calculated through an iterative process, and are accepted if the concerned matrices yield consistency ratios (CR) below a specific limit. Finally, composite priority (CP) values are calculated, and the alternatives are ranked according to their CP values. The algorithm is coded in FORTRAN language. The program is general, and can be used to handle smaller or larger number of criteria and alternatives as well.

 

IPC Code: Int. Cl.7 B29D 29/06

 

 

 

Indian Journal of Engineering & Materials Sciences

Vol. 11, October 2004, pp. 406-412

 

Effect of tyre overload and inflation pressure on rolling loss (resistance) and fuel consumption of
automobile and truck/bus tyres

Padmanabha S Pillai

 

The effect of rolling resistance R on fuel consumption of radial passenger and truck tires is discussed in this paper. The model equation for the rolling loss R was directly proportional to tire load W (R a W) and inversely proportional to inflation pressure p (R a 1/px). These relationships were experimentally quantified. Using manufacturer’s recommended values for load W and pressure p as reference points the R values for different overload conditions (from +10 to +100%) at constant p were estimated. Similarly, the required p values to support 10 to 50% additional load to maintain original R were also estimated. Then the estimated R values for different overload/inflation pressure conditions were combined with the fuel saving factor F (obtained from published literature results). Then the relative change in fuel consumption of truck/bus tires for different load/pressure combinations vis-a-vis the fuel use for the manufacturer’s recommended W and p values was evaluated. The present analysis showed that for the same amount of fuel use a truck carrying a 100% overload and making one round trip would correspond to slightly more than two round trips by a truck of same size carrying the recommended load. Finally, a possible method of optimizing fuel use by adjusting the tire load/pressure conditions was suggested. All these estimates were obtained for radial tires. The author feels that the same methodology is applicable for bias tires also.

 

IPC Code: Int. Cl.7 B60C 17/00, G01L 17/00

 

 

 

Indian Journal of Engineering & Materials Sciences

Vol. 11, October 2004, pp. 413-420

 

Optical and dielectric properties of organic laser dye Rhodamine 6G doped silica xerogels
with the variation of the sol-gel parameters

A Parvathy Rao & A Venkateswara Rao

 

The effect of sol-gel parameters such as pH of the alcosol, R6G/TEOS, H2O/TEOS and EtOH/TEOS molar ratios on the optical and dielectric characteristics of R6G doped silica xerogels are reported here. Optical absorption and emission have been studied in the visible range. The dielectric property such as dielectric permittivity () is carried out for pure and the R6G doped silica xerogels in the frequency range of the applied field (f) from 100 Hz to 1 MHz. It has been found that the optical and dielectric properties of the R6G doped silica xerogels are strongly dependent on the sol-gel parameters. Monolithicity and transparency of the R6G doped silica xerogels have also been studied. There is a remarkable shrinkage with the variation of the sol-gel parameters.

 

IPC Code: Int. Cl7 C 01 B 33/16

 

  

 

Indian Journal of Engineering & Materials Sciences

Vol. 11, October 2004, pp. 421-428

 

Theoretical approach to the tunneling mechanoluminescence produced during cleavage of
II-VI semiconductors  

Vibha Choudhary, Anubha Singh, V K Chandra, R K Gupta & B P Chandra

 

This paper describes the tunneling mechanoluminescence (ML) produced during fracture of II-VI semiconductors. The electric potential surrounding the charged dislocations bends, valence band and conduction band strongly and consequently, the electron centres float up in synchronism with the band bending as the dislocations core approaches starting distance from the dislocation core the process of electron tunneling from the centre into the conduction band becomes significant. Thus, a moving dislocation can transfer electrons form deep traps to the conduction band. These electrons subsequently recombine with the holes at impurity centres and give rise to luminescence, which is the characteristic of the centres. When a II-VI semiconductor is fractured or cleaved initially the mechanoluminescence (ML) intensity increases with time attains a peak value Im at the time tm corresponding to completion of the fracture of semiconductors. After the completion of fracture, the ML intensity decay with time, whereby the initial fast decay is controlled by the pinning time of dislocations and the subsequent slow decay is controlled by the lifetime of electrons in the shallow traps. In the ML produced during the fracture of II-VI semiconductors, both Im and IT increase directly with the area of the newly created surfaces of the crystals. The ML intensity of II-VI compounds decreases with temperature. Expressions are derived for the rise of ML intensity, and the total ML intensity. A good agreement is found between the theoretical and experimental results related to the ML produced during the cleavage of II-VI semiconductors.

 

IPC Code: Int. Cl.7 F21V 13/00, B28D 5/00

 

 

 

Indian Journal of Engineering & Materials Sciences

Vol. 11, October 2004, pp. 429-432

 

Predicting detonation velocity of ideal and less ideal explosives via specific impulse

M H Keshavarz & H R Pouretedal

 

A novel method is given to estimate the detonation velocity of mostly ideal and less ideal composition explosives. This method is based on the utilization of theoretical specific impulse of the explosive, which can be designated as a monopropellant, and loading density. The simple empirical equation in calculating the detonation velocity has the form: DCJ=1.453ISPr0 + 1.98, where DCJ is the Chapman-Jouguet detonation velocity, ISP is the specific impulse and r0 is the initial density. Calculated detonation velocity by this procedure shows good agreement with respect to measured detonation velocity.

 

IPC Code: Int.Cl.7 C06C

 

 

 

Indian Journal of Engineering & Materials Sciences

 Vol. 11, October 2004, pp. 433-437

  

Mineral industries and their environmental aspects in Indian context

Mrinal K Ghose & Anjay Kumar

 

The Indian mining industry indicates almost the full range of extractive mineral products. Mineral deposits are worked in areas, which are considered to be ecologically sensitive and environmental conservation is generally a major barrier for successful development of mines. This paper overviews the mineral production in India. It focuses on the key environmental issues and outlines a range of environmental impacts that are relevant to the planning of a modern mine. This paper identifies variety of mining operations and mining techniques to minimize environmental impacts, which cannot be standardized and no single element of mining can minimize environmental impacts.

 

IPC Code: Int. Cl.7 E 21 C

 

 

 

Indian Journal of Engineering & Materials Sciences

Vol. 11, October 2004, pp. 438-440

 

Effect of facet coatings on laser diode characteristics

P V Bhore, A P Shah, M R Gokhale, S Ghosh, A Bhattacharya & B M Arora

 

The cleaved facets of semiconductor diode lasers act like mirror. Mirror coatings are applied to change the reflectivity and passivate the surfaces. Design of antireflection coating is optimized for single layer of Al2O3 and high reflection coating is optimized for stacks of Al2O3 and Si Bragg reflector. Electron beam evaporation has been used to deposit uniform Al2O3/Si film under high vacuum with pressure 10-6 mbar and temperature 150-160°C. The optimization of experimental parameters for the dummy GaAs substrate has been discussed. Using these parameters laser facets were coated and changes in the L-I characteristics have been measured and investigated step by step. The output light power versus current characteristics of coated laser diode is compared with that of uncoated one for its characterization under pulsed conditions and have shown that the facet reflectivity has played a major role in determining threshold current density of semiconductor laser.

 

IPC Code: Int. Cl.7 H01S 5/028