012137   Vadapalli S;Usharani A;Chowdhary P S R;Gautam D K;Samuel E P;Patil D S (IACQER Member, Raghu Engineering College, Visakhapatnam, Email: edsaedwin@rediffmail.com) : Analysis of optical properties of quantum well ultra violet laser diode. Bionano Front 2010, ICLAM(spl), 1-2.

The near and far field intensities have been analyzed for better optical confinement and to explore the applicability of GaN based quantum well laser diode for high density optical storage. The 30% of Aluminum mole fraction was retained in Al_xGa_1-xN cladding layers. The results reveal that the L valley has ascendancy over other two inter-vallies for both far field and near field intensity. The near field confinement within the quantum well laser diode seems to be excellent. The overall length of the devices was kept to be 4 micron while the investigation for the field intensity was carried out for the 5 nanometerwide quantum well.

5 ref

012136   Unlu B S (Mechinery Dep, Vocational High School, Celal Bayar Univ, 45400-Turgutlu-Manisa, Turkey, Email: bekir.unlu@bayar.edu.tr) : Investigation of tribological and mechanical properties of metal bearings. Bull Mater Sci 2009, 32(4), 451-7.

Copper, aluminum and tin-lead based alloys are widely used as journal bearing materials in tri-bological applications. Bronze and brass are widely used as journal bearing materials for copper based alloys. Zamacs find applications as journal bearing materials for zinc based alloys, while duralumines are chosen as journal bearing materials for aluminum based alloys. In addition, white metals are widely used as journal bearing materials for tin-lead based alloys. These alloys ensure properties expected from journal bearings. In this study, tribological and mechanical properties of these journal bearings manufactured by metals were investigated. SAE 1050 steel shaft was used as counter abrader. Experiments were carried out in every 30 inin for a total of 150 min by using radial journal bearing wear test rig.

9 illus, 3 tables, 30 ref

012135   Twala B (NO, , Council of Scientific Industrial Research (CSIR), PO Box 395, Pretoria 0001, South Africa, Email: bwala1@csir.co.za) : Handling out-of-sequence data: kalman filter methods or statistical imputation?. Def Sci J 2010, 60(1), 87-99.

The issue of handling sensor measurements data over single and multiple lag delays also known as out-of-sequence measurement (OOSM) has been considered. It is argued that this problem can also be addressed using model-based imputation strategies and their application in comparison to Kalman filter (KF)-based approaches for a multi-sensor tracking prediction problem has also been demonstrated. The effectiveness of two model-based imputation procedures against five OOSM methods was investigated in Monte Carlo simulation experiments. The delayed measurements were either incorporated (or fused) at the time these were finally available (using OOSM methods) or imputed in a random way with higher probability of delays for multiple lags and lower probability of delays for a single lag (using single or multiple imputation). For single lag, estimates of target tracking computed from the observed data and those based on a data set in which the delayed measurements were imputed were equally unbiased; however, the KF estimates obtained using the Bayesian framework (BF-KF) were more precise. When the measurements were delayed in a multiple lag fashion, there were significant differences in bias or precision between multiple imputation (MI) and OOSM methods, with the former exhibiting a superior performance at nearly all levels of probability of measurement delay and range of manoeuvring indices. Researchers working on sensor data are encouraged to take advantage of software to implement delayed measurements using MI, as estimates of tracking are more precise and less biased in the presence of delayed multi-sensor data than those derived from an observed data analysis approach.

8 illus, 2 tables, 54 ref

012134   Talele K;Samuel E;Patil D S (Electronics Dep, North Maharashtra Univ, Jalgaon, Email: k_talete@yhoo.co.in) : Analysis of near field intensity of ZnO based superlattice nanostructure. Bionano Front 2010, ICLAM(spl), 50-1.

The analysis of near filed intensity of ZnO/MgZnO has been carried out. The near field intensity has been obtained through the solutions of Maxwell's equation solved in TE mode. The near filed intensity has the sharp peak at the centre of the devices, due to the different refractive index of ZnO/MgZnO material. As the concentration of magnesium in the barrier region increases the full width of half maxima (FWHM) decreases.

7 ref

012133   Sujatha K N;Kumari B A;Vaisakh K (Electrical Engineering Dep, Andhra Univ College of Engineering, Andhra Univ, Visakhapatnam-530 003, Email: knagasujatha@yahoo.co.in) : Fuzzy speed controller for scalar controlled induction motor drive. Icfai Univ J Sci Technol 2009, 5(3), 7-19.

Presents a fuzzy logic-based speed controller for scalar controlled closed loop Volts/Hz Induction Motor (IM) drive with slip regulation. The IM is modeled in terms of dq windings, with synchronous frame associated with the frequency ω of the stator excitation. The two inputs to the Fuzzy Logic Controller (FLC) are the linguistic variables of speed error and change of speed error, while the output is the frequency change. They are also compared with traditional Proportional-Integral (PI) controller and without controller. The results validate the effectiveness of the proposed FLC for scalar controlled (or) Volts/Hz IM drive which is considered as a highly nonlinear dynamic complex systems. Matlab/Simulink software was used to simulate the proposed model.

12 illus, 1 table, 11 ref

012132   Srinivasan K;Dash S S (NO, Sathyabama Univ, Chennai-600 119, Email: omsrivas@yahoo.co.in) : Comparison of component minimized Z - source inverter and six switch z - source inverter for motor drives. Natn J Technol 2009, 5(4), 14-22.

In this paper, two different inverters: Traditional PWM six switch Z-source inverter and component minimized [four switch three phase (FSTP) ] Z-source inverter for Induction Motor Drive were investigated. Total switching device power of each of these inverters was calculated. For purposes of comparison, an example of the total switching device power, requirement of passive components and the constant power speed ratio of the different inverters powered by the same source and loaded by the same motor were conducted. This comparison shows that the four switch Z-source inverter is very promising for Induction Motor Drive.

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012131   Sohani D A;Shrivastava V S (Centre for P.G. Research in Chemistry, G.T.P. College, Nandurbar-425 412) : Impact of industrial waste on seed germination and metals uptake : a bio-accumalation study. Asian J chem envir Res 2009, 2(3-4), 79-81.

Bioaccumulation of Industrial waste by Arachis hypogea was investigated by performing pot experiment (In-situ and In-vitro). The plants were treated with different concentrations of the industrial waste through soil in four weeks. During this period the germination, length of root and shoot was observed. After the completion of experiment total dry mass, chlorophyll content, carbohydrate, protein was also calculated. In the industrial waste and the experimental plants the concentration of metals like Ni, Cr, Zn, Fe, Cu, Cd were analysed by ICP-AES.

4 tables, 12 ref

012130   Singh G K;Gopal A (NO, National Aerospace Laboratories, Bangalore, Email: gksnal@rediffmail.com) : Path planning in the presence of dynamically moving obstacles with uncertainty. Def Sci J 2010, 60(1), 55-60.

The problem of path-planning with dynamically moving elliptical obstacles is addressed. A new analytical result for computing the axes aligned bounding box for the ellipses with bounded uncertainty in the position of the centre and the orientation is presented. Genetic algorithm is utilised for finding the shortest path from the initial to goal position avoiding the moving obstacles.

3 illus, 12 ref

012129   Singh C (Economics Dep, Nitishwar Singh College, Sarmastpur, Muzaffarpur, Email: c.chandrakantsingh@gmail.com) : Impact of new technologies on precision agriculture. Bull agric Sci 2009, 7(1), 23-6.

Agriculture assumes immense importance in India's economy. The rise of newer sciences in agriculture along with the development of new technologies, products and processes had resulted in transferring farm innovations to farmers a difficult task. Though complicated in nature during the production process, the end product has many desirable traits compared to traditionally evolved technologies. Few innovations had replaced chemical fertilizers herbicides and pesticides in the Agricultural production system. Moreover many new technologies namely use of bio-fertilizers, bio-pesticides, use of tissue culture plant has helped fanners achieve greater productivity gains and also realize good profits. However, many of these technologies developed over years are yet to be communicated to a major of farm populations.

5 ref

012128   Shrivastava J (Electrical Engineering Dep, Allahabad Agricultural Institute - Deemed Univ, Allahabad-211 007) : Comparing vegetable oil with mineral oil as a dielectric for power transformers. Allahabad Fmr 2009, 64(2), 7-19.

The transformers generate significant amounts of heat and must contain cooling and insulating mediums to prevent gas formation, electrical shorts, fire, explosion and transformer damage. The media can be solid, liquid such as mineral oil, high molecular weight hydrocarbons (HMWHs), synthetic oil such as silicone or gas such as sulfur hexafluoride. Most transformers currently use some type of mineral oil as the cooling fluid; however HMWHs and synthetics (less- flammable fluids) are used in transformers that operate in safety related applications. Recently, transformer oil suppliers have developed vegetable seed oil -based dielectric fluid. These fluids have been certified as meeting less-flammable safety related requirements. Distribution and power transformers store oil in range of 100 litre to 100 kilolitre. Spills from transformers are potentially an environment concern because even small amounts of oil can contaminate bodies of water, possibly deplete oxygen, coat plant and animal life, be toxic or form toxic products, after breeding, produce rancid odors, or foul shoreline or other habitats. This paper discusses technical issues of vegetable oil like dielectric, thermal manufacturing, monitoring environmental. Although vegetable oil is expensive by 20 to 30% to widely used mineral oil its flash and fire point are quite high and reduces ageing of paper.

3 illus, 4 tables, 9 ref

012127   Seotsanyana M (NO, Council for Scientific and Industrial Research, Pretoria, South Africa, Email: mseotsanyana@csir.co.za) : Temporal logic motion planning. Def Sci J 2010, 60(1), 23-38.

A critical review on temporal logic motion planning is presented. The review paper aims to address the following problems: (a) In a realistic situation, the motion planning problem is carried out in real-time, in a dynamic, uncertain and ever-changing environment, and (b) The accomplishment of high-level specification tasks which are more than just the traditional planning problem (i.e., start at initial state A and go to the goal state B) are considered. The use of theory of computation and formal methods, tools and techniques present a promising direction of research in solving motion planning problems that are influenced by high-level specification of complex tasks. The review, therefore, focuses only on those papers that use the aforementioned tools and techniques to solve a motion planning problem. A proposed robust platform that deals with the complexity of more expressive temporal logics is also presented.

4 illus, 1 table, 41 ref

012126   Savanur S R;Patel A V (NO, B.L.D.E.A's College of Engineering and Technology, Bijapur, Email: srsavanur@yahoo.co.in) : Sensor/control surface fault detection and reconfiguration using fuzzy logic. Def Sci J 2010, 60(1), 76-86.

In the aircraft flight control systems, a quick detection of the faults, that occur in actuators, control surfaces or sensors, is necessary. In this paper, sensor fault detection and reconfiguration is performed using Kalman filter by estimating the states of the plant and comparing them with respective measured values from the sensors. Sensor fault detection and reconfiguration is carried out using non-model-based fuzzy logic technique. Control surface fault detection and reconfiguration is carried out by identifying the elements of control distribution matrix using extended Kalman filter and fuzzy logic. In estimating the factor of effectiveness of the control surface using fuzzy logic, different implication methods such as Mamadani's minimum, Larsen's product, bounded product and drastic product have been used and a comparison is made.

20 illus, 6 tables, 12 ref

012125   Satish Kumar D;Gautam D K;Samuel E P (NO, IACQER Raghu Engineering College, Visakhapatnam, Email: edsaedwin@rediffmail.com) : Exploration of photonic crystal fibers as gas sensors. Bionano Front 2010, ICLAM(spl), 67-8.

Deals present the gas sensing capability of the porous photonic crystal fibers. The relative have been found to be increasing with the increase in the wavelength of the light source traveling in the photonic crystal fiber waveguide. The gas concentrations with respect time and distance have been calculated. It was realized that the transmittance with respect to increasing time decreases exponentially. The transfer matrix method has been utilized to solve the general solutions of the Maxwell equation, while the integration has been obtained by using Simpson's method. The MATLAB software have been utilized for developing the simulation tools for obtaining high accuracy to predicate the sensitivity of gases realized in the photonic crystal cavities.

3 illus, 4 ref

012124   Sameena N M;Konda R B;Mulgi S N;Hunagund P V (PG Studies and Research in Applied Electronics Dep, Gulberga Univ, Gulberga, Email: sameena.nm@rediffmail.com) : Novel slot for enhancing impedance bandwidth and gain of microstrip antenna. Icfai Univ J Sci Technol 2009, 5(3), 64-70.

The paper exhibits a novel design of slot rectangular Microstrip Antenna (MSAs) for dual band operation at 7.28 to 7.37 GHz and 7.62 to 7.88 GHz with corresponding impedance bandwidth of 1.22% and 3.35%, respectively, and a gain of -9.68 dB. By loading a slot of plus shape on the ground plane of this antenna, the dual band merges into single band, i.e., at 6.45 to 7.9 GHz with a total impedance bandwidth of 20.2% with an increased gain of 2.55 dB without changing the nature of broadside radiation characteristics. These dual, wideband and high gain antennas may find application in WLAN systems. Details of antenna design are described and the experimental results are discussed.

6 illus, 1 table, 5 ref

012123   Sakri M I;Saravanan S;Mohanram P V;Syath Abuthakeer S (NO, PSG College of Technology, Coimbatore-641 004) : Estimation of fatigue-life of electronic packages subjected to random vibration load. Def Sci J 2009, 59(1), 58-62.

Random vibration is being specified lor acceptance tests, screening tests, and qualification tests by manufacturers of electronic equipment meant for military applications, because it has been shown that random vibration more closely represents the true environment in which the electronic equipment must operate. In this paper, the methodology of testing an electronic package subjected to random vibration load is illustrated using Joint Electronic Device Engineering Council's (JEDEC) JESD22-1BI03B standard. The electronic package mounted at the centre of the printed circuit board was subjected to vibration, variable frequency condition 'D' of JEDEC standard for 30 min. After 30 min of random vibration test, the component lead-wires, solder-joints, and PCB were thoroughly inspected for failure. From the observations, it was found thai no failure occurred during the test period. The fatigue life of the component, estimated using analytical method, was found to be 96.48 hours.

8 illus, 3 tables, 12 ref

012122   Sadagopan P (Automobile Engineering Dep, PSG College of Technology, Coimbatore-641 004) : Performance evaluation of muffler of a minidor vehicle with the modified muffler. Natn J Technol 2009, 5(4), 27-36.

Automotive Industries in India is undergoing a sea change in Technology due to global competition and stringent norms on noise and exhaust gas pollution. Noise level emanated from cars on Indian Roads are generally low compared to commercial vehicles and is significantly high in the case of minidor499cc three wheelers. Exhaust noise of 1C engines is the main component of noise pollution of the urban environment. To attenuate the exhaust noise, expansion chambers with different configuration has become an important area of research and development. In this present work, performance on noise, pressure drop and velocity of exhaust gas of the existing muffler of minidor 499 cc diesel engine is made. By using the model based on Sterrett, a modified multi chamber muffler was fabricated and its performance was measured on similar grounds and the results are compared. It is observed that the modified design of muffler is having a better performance.

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012121   Ravichandran A;Mohanasundaram K M;Raja Murugadoss J (Mechanical Engineering Dep, Bannari Amman Institute of Technology, Sathyamangalam-638 401, Email: atrmathy@rediffmail.com) : Order picking distance of a multiple cross aisle warehouse using an enhanced ANT colony algorithm. Natn J Technol 2009, 5(4), 56-65.

This paper aims at introducing an enhanced version of ant based optimization technique namely, "Block Based Multiple Ant Colony (BB-MAC)" algorithm. The proposed algorithm is implemented to minimize the order picking distance/time which is considered to be the most labor-intensive and capital-intensive part of warehouse operations. The applicability of the suggested algorithm is experimented with a standard well known order picking problem, a discrete unconstrained optimization problem reported in literature. It is further extended for few more similar problems to handle high pick loads. Results reveal that the algorithm is intuitively superior in generating some more improved solutions at the end of each iteration rather than converging to infeasible solutions as prevailing in other algorithm.

8 illus, 13 tables, 7 ref

012120   Ravi Kumar B V R;Soni J S (Mechanical Engineering Dep, VNR Vignana Jyothi Institute of Engineering and Technology, Bachupally, Hyderabad-500 090, Email: raviraj-1970@yahoo.com) : Microstructure and properties of welded 15CDV6 alloy steel. Icfai Univ J Sci Technol 2009, 5(2), 7-25.

The study of non-destructive testing, tensiZe test of weldments have been carried out on a 15CDV6 alloy steel using Gas Tungsten Arc Welding fGTAW) with non-pulsed and pulsed current at different frequencies-2, 4 and 6 Hz respectively. The radiography, liquid penetrant test and mechanical properties of the iveldments have been evaluated and compared with non-pulsed and pulsed current welding at different frequencies. The radiography, liquid penetrant test and tensile test have been carried out on the weldments of the above material having two different thicknesses, i.e., 1.5 and 5.0 mm of 15CDV6 alloy steel. This study also presents the weld joint efficiency of the material at different welding process parameters. The aim of this study is to see the effect of pulsed current on the quality of weldments. The experimental results pertaining to different welding parameters for the above alloys using pulsed and non-pulsed current GTAW are discussed and compared. This paper also covers the weld microstructure development of the weldments carried out using pulsed and non-pulsed current GTAW. In order to improve the mechanical integrity of the weldments, it would be desirable to study the microstructure of the weld Fusion Zone (FZ) and Heat Affected Zone (HAZ). This study has been performed in order to show the differences in macro and microstructure of the weldments made with non-pulsed and pulsed current at different frequencies of GTAW.

20 illus, 10 tables, 14 ref

012119   Ravi Krishna;Surit R;Kushari A;Ghosh A K (NO, Aerial Delivery Research and Development Establishment, Agra-282 001) : Anomalies in the flow over projectile with wrap-around fins. Def Sci J 2009, 59(5), 471-84.

This paper presents the results of a numerical study to understand the flow field over a projectile with wraparound fins. This investigation is performed in order to determine aerodynamic coefficients for the missile model for varying Mach number from 1.2 to 2.5. The roll moment coefficients were computed from the flow field solution and compared with other computational models and experimental works. The results show a reversal of the rolling moment in a Mach number from 1.2 to 1.4. While generating Mach number profile along missile body, a transition from subsonic to supersonic flow was notably found just before the fin-tip in the Mach number range from 1.2 to 1.4. This transition from subsonic to supersonic just before the fin seems to be the main cause for the roll reversal, which makes the flow inside the fin passage behave differently. Furthermore, it was seen that most of the effect was confined towards the leading edge of the fins.

2 illus, 1 table, 21 ref

012118   Rathod S M;Rajuskar R S (Physics Dep, Abasahab Garware College, Pune-4) : Simulation of power MOSFET circuit for pulsed lasers. Bionano Front 2010, ICLAM(spl), 21-2.

Study the considerable work done on base of simulation of Power MOSFET circuits used for pulsed lasers. Power MOSFET have been used in development of pulsed power generators used in industrial applications. For effective laser pumping high voltage pulses (kV) with the pulse rise time in <10ns is necessary. A high speed switching Power MOSFET circuits with >1 kV is simulated using PSpice. This work will provide to design and construction of pulsed laser for good efficient power.

5 illus, 3 ref

012117   Ramanathan P;Vanathi P T (ECE Dep, PSG College of Technology, Coimbatore) : Novel decomposition algorithm for power delay product optimization in wallace and carry save multipliers. Natn J Technol 2009, 5(4), 92-100.

The need for low power has caused a major paradigm shift where power dissipation has become as important a consideration as performance and area. Multiplier forms the core of a Digital Signal Processor and is a major source of power dissipation. Often, the multiplier forms the limiting factor for the maximum speed of operation of a Digital Signal Processor. Due to continuing integrating intensity and growing needs of portable devices, low-power, high-performance design is of prime importance. A new technique of implementing multiplier circuit using Decomposition Logic is proposed which improves power delay product when compared to conventional tree structured Wallace multiplier. In this paper, 8x8 and 16x16 Wallace multiplier and Carry Save multiplier structures have been designed using the proposed decomposition algorithm. The power delay product of the multipliers implemented using the proposed decomposition algorithm was found to be lesser when compared to the conventional Wallace and carry save multiplier structures. The design was done using three different families, namely CMOS, CPL and HYBRID EXOR. Tanner EDA was used for simulation in the TSMC180nm technology, with a supply voltage of 1.8 V.

11 illus, 8 tables, 12 ref

012116   Radhakrishnan R;Ravi Shankar S (Statistics Dep, PSG College of Arts & Science, Coimbatore-641 014) : Three class attributes single sampling plan indexed through inflection point. Natn J Technol 2009, 5(4), 70-6.

Traditionally, 2-class sampling plans are used to classify the lot of items as acceptable or non-acceptable by considering only the number of non-conformities found in the sample. These plans do not provide any consideration for marginal defective items. By considering the near miss item as marginal, the 3-class sampling plans are used in food and pharmaceutical industries to take a decision to accept or reject a lot based on not only the number of nonconformities; but also on the number of marginal items. This paper presents a procedure for constructing the Single Sampling Plan for three attribute classes indexed through Maximum Allowable Percent Defective (p*) and the relative slope (h*) at the inflection point. A table is also constructed for easy selection of these plans.

4 illus, 1 table, 18 ref

012115   Prabha;Goswami K;Chatterjee B (Humanities and Social Sciences Dep, Indian Institute of Technology, Kharagpur-721 302) : Impact of infrastructure and technology on agricultural productivity in Uttar Pradesh. Agric Econ Res Rev 2009, 22(1), 61-70.

Trends of composite and individual infrastructural indicators, fertilizer and HYVs have been examined and their impacts on agricultural productivity in Uttar Pradesh have been reported. The trend of composite infrastructure index has shown sharp fluctuations, while electrified villages and rural roads have indicated a rising trend. The agricultural productivity and fertilizer have shown increasing trend with marginal fluctuations, while HYVs have illustrated an increasing trend at a decreasing rate. The impact of composite infrastructure index, fertilizer and HYVs on agricultural productivity has been found positive and significant. Analysis of the impact of individual infrastructural indicators has revealed that the electrified villages along with fertilizer and HYVs have positive and significant impact, while rural roads have an insignificant impact.

6 illus, 3 tables, 16 ref

012114   Patil A B;Saraf K B (P.G. Dep of Physics, Pratap College, Amalner-425 401) : Spherulites of mercuric iodate grown by gel technique and its analysis. Asian J chem envir Res 2009, 2(3-4), 69-74.

Spherulites of Mercuric iodate were grown by a simple gel technique using diffusion method. The optimum growth conditions were established by varying various parameters such as pH of the gel solution, gel concentration, gel setting time, concentrations of reactants etc. Spherulitic crystals of mercuric iodate were obtained and were opaque. The crystals were characterized using XRD, TGA/DTA, FT-1R and EDAX.

4 illus, 4 tables, 9 ref

012113   Padmanabhan S;Sukhi Y;Jeyashree Y (ECE Dep, AVIT, Chennai, Email: spgaythri@hexaware.com) : Application of soft switching inverter for regulated power supply. Natn J Technol 2009, 5(4), 45-55.

Proposes a soft switching dc-dc converter topology in which a series parallel resonant converter is coupled by a high frequency transformer to the load. The topology offers pulse width modulation for the dc-ac conversion. It is shown that soft switching technique reduces the switching losses either by zero-voltage or zero-current switching conditions for all semiconductor devices in all points of operation. The analysis is done for the different modes of operation. The design and operation of a 60W, 1.5A and 40V prototype converter system is described. Experimental results obtained from a laboratory prototype are presented.

17 illus, 4 tables, 10 ref

012112   Niranjan Kumar M S R;Sarcar M M M;Balakrishna Murthy V;Rao K M (Production Engineering Dep, V.R. Siddhartha Engineering College, Vijayawada-520 007, Email: m_niranjankumar@rediffmail.com) : Effect of ellipse orientation on the thermoelastic behaviour of skew laminated composite plate with elliptical cutout. Bull Mater Sci 2009, 32(1), 59-64.

An effort is made to study the thermoelastic behaviour of a cross-ply laminated composite skew plate with elliptical cutout subjected to pressure and non-linearly varying temperature loading in the present analysis. Orientation of the elliptical cut out is varied from 0° to 180° with respect to horizontal at an interval of 30° in the anti clockwise direction is considered for the present analysis. A three-dimensional heat conduction analysis in fibre reinforced composite laminates has been simulated by finite element method to get realistic temperature in the laminate under different thermal boundary conditions. A finite element method, which works on the basis of three-dimensional theory of elasticity, is employed to evaluate the stresses and deformations. The effect of orientation due to pressure loading on the stresses and transverse deflection is observed to be insignificant. The magnitudes of the in-plane normal stresses, σ_x and (σ_y for temperature loading are greatly affected by ellipse orientation and are observed to be minimum at the ellipse orientation of 0° and 90°, respectively. The in-plane and inter-laminar shear stresses are observed to be minimum at the ellipse orientation.

8 illus, 1 table, 10 ref

012111   Naskar M K;Kundu D;Chatterjee M (Sol-Gel Div, Central Glass and Ceramic Research Institute (Council of Scientific an, Kolkata-700 032, Email: milan@cgcri.res.in) : Silicalite-a zeolite membranes on unmodified and modified surfaces of ceramic supports: a comparative study. Bull Mater Sci 2009, 32(5), 537-41.

Silicalite-1 zeolite membranes were prepared hydrothermally on the porous ceramic supports, both unmodified and modified with 3-aminopropyl triethoxysilane (APTES) as a coupling agent following ex situ (secondary) crystal growth process. The microstructure of the membranes was examined by scanning electron microscopy (SEM). The permeation study with a single gas, nitrogen (N₂) was performed through the membranes. For the surface modified support, a more surface coverage of the seed crystals on the porous support was observed resulting in a relatively higher dense packing of the crystals during secondary crystal growth process compared to that obtained from the unmodified support. The membrane developed on surface modified support rendered lower permeance value i.e. 9 x 10^{-7 mol m-2s-1 Pa-1 of N₂ compared to that formed on the unmodified support which gave permeance value of 20 x 10_-7 rnol m2 s-1 Pa-1 of N₂.}

8 illus, 23 ref

012110   Naidu V P S (NO, National Aerospace Laboratories, Bangalore, Email: vpsnaidu@gmail.com) : Discrete cosine transform-based image fusion. Def Sci J 2010, 60(1), 48-54.

Image fusion by multi-resolution discrete cosine transform (MDCT) algorithm has been implemented and evaluated. The performance of this algorithm is compared with that of well known image fusion technique using wavelets. It is observed that image fusion by MDCT perform almost similar to that of wavelets. It is computationally very simple and it could be well suited for real time applications.

9 illus, 1 table, 36 ref

012109   Mtshali M;Engelbrecht A (NO, , Council for Scientific and Industrial Research, Pretoria, South Africa, Email: mmtshali@csir.co.za) : Robotic architectures. Def Sci J 2010, 60(1), 15-22.

In the development of mobile robotic systems, a robotic architecture plays a crucial role in interconnecting all the sub-systems and controlling the system. The design of robotic architectures for mobile autonomous robots is a challenging and complex task. With a number of existing architectures and tools to choose from, a review of the existing robotic architecture is essential. This paper surveys the different paradigms in robotic architectures. A classification of the existing robotic architectures and comparison of different proposals attributes and properties have been carried out. The paper also provides a view on the current state of designing robot architectures. It also proposes a conceptual model of a generalised robotic architecture for mobile autonomous robots.

8 illus, 2 tables, 41 ref

012108   Moses S C;Alam R N;Tripathi A (Farm Machinery and Power Engg Dep, College of Agricultural Engineering, Allahabad Agricultural Institute-Deemed Univ, Allahabad-211 007) : Feasibility study of light weight rotary tiller for seed bed preparation in Allahabad region. Allahabad Fmr 2009, 65(1), 15-21.

The feasibility test of light weight rotary tiller was conducted in the research farm of AAI-DU. The present study finds the effect of three levels of speed and depth of operation on actual field capacity, field efficiency, fuels consumption and soil mean weight diameter. Actual field capacity increased as speed increased and decreased as depth of operation increased. Field efficiency decreased with increase in speed as well as depth of operation. Fuel consumption increased with speed and depth of operation. Mean weight diameter decreased with increase in speed as well as depth of operation. Cost of operation with rotary tiller was estimated to be Rs. 815.17 and was found to be economical by Rs. 384.83 per hectare as compared to that of bullock drawn implements. Since, in case of seedbed preparation, more depth is required so the machine can be recommended to be used at maximum depth of 10 cm and maximum speed of 1.57 km/h. Although the field efficiency is lesser and fuel consumption is higher at this depth and speed of operation, but the field capacity and soil pulverization are very good.

2 tables, 5 ref

012107   Moses S C;Aalam R N;D'Souza P M (Farm Machinery and Power Engg. Dep, College of Agricultural Engineering and Technology, Allahabad Agricult, Allahabad-211 007) : Field testing of self propelled power weeder for brinjal and sugarcane crop. Allahabad Fmr 2009, 64(2), 32-6.

The performance of a self-propelled power weeder manufactured by Amar Farm Equipment Ltd. was evaluated. The self-propelled power weeder was tested at village Dadri, Chaka Block, Allahabad on Brinjal and Sugarcane crop. The weeding efficiency, plant damage and fuel consumption were observed. The weeding efficiency in Brinjal and Sugarcane were found at 68.2% and 82.5% respectively. The weeding efficiency was found increasing with increase in depth of operation. The plant damage was minimum at depth of 30 mm in Brinjal crop and found maximum at depth of 50 mm in Sugarcane crop. The fuel consumption was minimum at 30 mm depth in both crops. The actual field capacity found in brinjal was 0.051 ha/hr and in sugarcane crop 0.032 ha/hr at 40 mm depth. The cost of operation with power weeder in Brinjal was Rs.1935/ha and in Sugarcane Rs.l332/ha against Rs.2580/ha and Rs.2430/ha for manual weeding respectively. The saving in cost of weeding in Brinjal was 25% and in Sugarcane was 45.2%. The actual field capacity found in Brinjal crop was 0.051 ha/hr and in Sugarcane was 0.032 ha/hr.

2 tables, 4 ref

012106   Malhotra N;Hari Singh (School of Mechanical Engineering, Shri Mata Vaishno Devi Univ, Kakrial, Jammu, Jammu & Kashmir, Email: navdeep_malhotra2001@yahoo.com) : Effects of process parameters and flushing techniques on surface roughness in EDM. Natn J Technol 2009, 5(4), 23-6.

Surface roughness, an indicator of surface quality, is one of the most specified customer requirements in machining parts. Surface roughness influences not only the dimensional accuracy of machined parts, but also their properties. In this research, one variable at a time approach is used to investigate the effect of type of flushing method along with six controlled input variables - Discharge Current, Voltage, Spark Gap, Ton, Toff and Flushing rate, on surface roughness of EDMed parts. The objective of this paper is to study the comparison & optimization of machining process parameters to obtain high surface finish in Electro-discharge Machining. The experiments were conducted on EN 31 & round copper tools with kerosene as dielectric under center flushing & side flushing. The experiment has shown that machining parameters & flushing conditions had large effect on surface roughness.

9 illus, 14 tables

012105   Maini A K;Verma A L (NO, Laser Science and Technology Centre, Metcalfe House, Delhi-110 054) : Pre-flight functionality check to enhance mission efficacy of precision guided munitions. Def Sci J 2009, 59(5), 459-65.

Precision-guided munitions (PGMs), because of their precision strike capability, are used extensively in the modern warfare. The efficacy of the mission is critically dependent on the successful deployment of the weapon. To ensure high level of effectiveness of these sophisticated weapons, these must be tested at regular intervals. Periodic functionality checks of these weapons are carried out using comprehensive characterisation systems. In addition to comprehensive testing, pre-flight functionality checks with the weapon strapped on to the launch platform using portable test systems should be carried out. These functionality checks, also referred to as serviceability checks, perform Go/No Go testing of the weapon by focusing on one or two vital parameters of the guided weapon. Pre-flight functionality check of PGM allows a quick appraisal on the functional status of the vital operational parameters of relevance to efficacy of the mission. This review highlights the parameters that need to be checked, both for comprehensive testing of these weapons on a periodic basis and also those required for pre-flight functionality or readiness checks. International systems available for the purpose have also been reviewed, vis-a-vis, their capabilities and limitations to perform the two types of tests with particular emphasis on the pre-flight functionality checks with guided weapon in strap-on condition. Some alternative design approaches have also been proposed.

14 illus, 7 ref

012104   Mahesh V;Kandaswamy A;Venkatesan R (Information Technology Dep, PSG College of Technology, Coimbatore, Email: vm@ity.psgtech.ac.in) : Neural classification of heart murmurs using wavelet decomposition. Natn J Technol 2009, 5(4), 37-44.

Heart auscultation is a non-invasive diagnostic technique used for the detection and classification of heart disorders. The diagnostic accuracy depends upon the physician's listening skills and interpretation. The results are therefore subjective. To circumvent the subjective inaccuracies and support the physician in his decision making, the development of a computer aided technique for heart sound analysis is presented hi this paper. Heart murmur files, normal and pathological, obtained from different internet sites are used in this work. These files are first preprocessed. Preprocessing includes conversion from mp3 to wav format and denoising. Each murmur file is segmented and only the portion of interest is extracted. Wavelet transform is used to decompose the signal into subbands. Coefficients obtained in each subband are used to calculate a set of time and frequency related parameters. These parameters form the input feature vector for a two layer feedforward artificial neural network trained using supervised learning with back propagation algorithm. The network classifies heart sounds into eight types viz., normal, early systolic, mid systolic, late systolic, holo systolic, early diastolic, mid diastolic and late diastolic. The classification performance of the neural network, expressed in terms of specificity, sensitivity and overall accuracy are 98.86 %, 100 % and 99.02 % respectively. The results demonstrate that the developed system can be a support tool for physicians in detecting heart disorders.

5 illus, 6 tables, 14 ref

012103   Madhavi M;Rao K V J;Rao K N (NO, M.V.S.R. Engineering College, Hyderabad-500 079) : Design and analysis of filament wound composite pressure vessel with integrated-end domes. Def Sci J 2009, 59(1), 73-81.

Filament-wound composite pressure vessels are an important type of high-pressure container that is widely used in the commercial and aerospace industries. The pressure vessels with integrated end domes develop hoop stresses that are twice longitudinal stresses and when isotropic materials like metals arc used for realizing the hardware, the material is not fully utilized in the longitudinal/meridonial direction resulting in over weight components. On the other hand FRP composite materials with their higher specific strength and moduli and tailoribility characteristics will result in reduction of weight of the structure. The determination of a proper winding angle and thickness is very important to decrease manufacturing difficulties and to increase structural efficiency. In this study, material characterization of FRP of carbon T300/Epoxy for variou-s configurations as per ASTM standards is experimentally determined using filament winding and matched die mould technique. The mechanical and physical properties thus obtained are used in the design of the composite shell. The design of the composite shell is described in detail. Netting analysis is used for the calculation of hoop and helical thickness of the shell. A balanced symmetric ply sequence for carbon T300/cpoxy is considered for the entire pressure vessel. Progressive failure analysis of composite pressure vessel with geodesic end domes is carried out. A software code SHELL Solver is developed using Classical Lamination-theory to determine matrix crack failure, burst pressure values at various positions of the shell. The results can be utilized to understand structural characteristics of filament wound pressure vessels with integrated end domes.

11 illus, 3 tables, 13 ref

012102   Madej W (NO, Koszalin Univ of Technology, 2 Sniadeckich St. 75-453, Koszalin, Poland) : Computations of coordinates in a multidimensional digital prediction system. Def Sci J 2009, 59(5), 530-6.

Prediction of the meeting point for air targets moving in the space with a high velocity and possessing the manoeuverable ability requires considering of the advance point corresponding the shift of the target during the flight of the missile to the target. In the paper, the procedure of computing of coordinates of the moving object (target) used for prediction of the meeting point in the multidimensional digital prediction system is presented. The multidimensional system is understood as a system possessing many systems of coordinates and mutual correlations between them. This system must realize all tasks in a real time.

^ssc10 illus, 13 ref

012101   Linga Murthy A;Krishna Y;Murti V S R (NO, Research Center Imarat, Hyderabad-500 069) : Design of packaging for microballoon actuators and feasibility of their integration within aerodynamic flight vehicle. Def Sci J 2009, 59(5), 485-93.

The microballoon actuators are used for the active flow control in turbulent boundary layer for aerodynamic control of flight vehicles. The packaging, interfacing, and integration of the microballoon actuators within the flight vehicle play a key role for functioning of the microballoon actuators during the flight conditions. This paper addresses the design and analysis of packaging and integration aspects and associated issues. The use of microballoon actuators on the control surfaces and nose cone of flight vehicles has the positive influence of delaying the flow separation from the aerodynamic surface. This results in enhancing aerodynamic effectiveness and lift as well as reduction of drag. A typical control surface is configured with eight microballoon actuators symmetric wrt the hinge line of the control surface and embedded within the control surface. Provision of the Pneumatic feed line system for inflation and deflation of the microballoons within the control surface has been made. The nose cone has been designed to have 32 such actuators at the circular periphery. The design is found to be completely feasible for the incorporation of microballoon actuators, both in the nose cone and in the control surface.

17 illus, 1 table, 6 ref

012100   Lin T;Jia D;Wang M;He P;Liang D (NO, Institute for Advanced Ceramics, Harbin 150001, People's Republic of China, China, Email: dcjia@it.edu.cn) : Effect of fibre content on mechanical properties and fracture behaviour of short carbon fibre reinforced geopolymer matrix composites. Bull Mater Sci 2009, 32(1), 77-81.

Geopolymer matrix composites reinforced with different volume fractions of short carbon fibres (C_f/geopolymer composites) were prepared and the mechanical properties, fracture behaviour and micro-structure of as-prepared composites were studied and correlated with fibre content. The results show that short carbon fibres have a great strengthening and toughening effect at low volume percentages of fibres (3.5 and 4.5 vol.%). With the increase of fibre content, the strengthening and toughening effect of short carbon fibres reduce, possibly due to fibre damage, formation of high shear stresses at intersect between fibres and strong interface cohesion of fibre/matrix under higher forming pressure. The property improvements are primarily based on the network structure of short carbon fibre preform and the predominant strengthening and toughening mechanisms are attributed to the apparent fibre bridging and pulling-out effect.

8 illus, 1 table, 11 ref

012099   Kushwah V S;Tomar G S (NO, Amity School of Engineering and Technology, New Delhi, Email: vive_kushwah@rediffmail.com) : Design of microstrip patch antennas using neural network. Icfai Univ J Sci Technol 2009, 5(2), 59-71.

Presents the general design ofmicrostrip antennas using Artificial Neural Networks (ANN) for rectangular patch geometry. The design consists of synthesis as the forward side and analysis as the reverse side of the problem. In this work, the neural network is employed as a tool in the design of microstrip antennas. The neural network training algorithms are used for training the samples to minimize the error and to obtain the geometric dimensions of patch antenna with high accuracy for selective band of frequencies using reverse modeling.

10 illus, 5 tables

012098   Kumar S;Tewari P C;Sunand Kumar (Mechanical Engineering Dep, AKG Engineering College, Ghaziabad-201 009, Email: getsan25@rediffmail.com) : Performance modeling and decision support system for desulphurization system of a fertilizer plant. Icfai Univ J Sci Technol 2009, 5(3), 41-52.

Discusses performance modeling and decision support system for the desulphurization system of a fertilizer plant using the concept of performance analysis and modeling. The fertilizer plant comprises various systems, viz., shell gasification and carbon recovery, desulphurization, co- shift conversion, decarbonation, nitrogen wash and ammonia synthesis, etc. One of the most important functionaries of a fertilizer plant is the desulphurization system. The desulphurization system of a fertilizer plant has five main subsystems arranged in series. The decision support system for desulphurization system has been developed with the help of performance modeling using probabilistic approach. After drawing the transition diagram, differential equations have been generated. The steady state probabilities are then determined. This availability model (i.e., measure of performance) deals with the quantitative analysis of all factors (courses of action and states of nature), which influence all maintenance decisions associated with the desulphurization system. The results of this paper are useful for the performance evaluation of the fertilizer plant concerned.

5 illus, 4 tables, 15 ref

012097   Kumar D;Mishra R N (Directorate of Standardisation, Ministry of Defence, New Delhi-110 011) : Angular orientation of anti-aircraft gun for interception of a moving air target. Def Sci J 2009, 59(1), 3-14.

Considers the problem of angular orientation of anti-aircraft guns towards a moving air target. The factors affecting the collision of the projectile fired from a gun with the moving air target arc highlighted. Thereafter, a mathematical model has been developed to estimate the angular orientation of the anti-aircraft gun in terms of bearing and elevation, in the direction of the predicted future position of the moving air target, to enable collision of the projectile with the target.

6 illus, 3 tables, 14 ref

012096   Kulkarni R K;Rajput S P S (Mechanical Engineering Dep, Maulana Azad National Institute of Technology, Bhopal-462 051, Email: rkk288in@gmail.com) : Performance evaluation of evaporative cooling pads of alternative materials and shapes suitable for seocnd stage. Asian J expl Sci 2010, 24(1), 141-50.

Evaporative coolers are normally operated as direct evaporative coolers with wetted pads. Addition of an indirect pre-cooler stage increases their efficiency. In this study, rectangular, cylindrical and hexagonal shapes suitable for use in direct stage with rigid cellulose, corrugated paper, high density polythene packing and aspen fiber materials are analyzed for performance. The geometrical parameters of pad like volume, wetted surface area and mass flow rate of air and performance parameters like saturation efficiency, outlet temperature of air and cooling capacity are calculated for velocities between 0.75 to 2.25 m/s. The effect of air mass flow rate on the saturation efficiency for different shapes of each material is shown. Rectangular shape gives highest efficiency of about 89% with aspen material and lowest of 80% with cellulose material for mass flow rates of about 0.3 kg/s. Cylindrical and hexagonal shapes have highest efficiency of about 83% with aspen material and lowest 72% with cellulose material for mass flow rates of about 0.4 kg/s. These efficiencies decrease with increase in mass flow rate of air and decrease in wetted surface area of the material. Drop in dry bulb temperature of air decreases with mass flow rate where as cooling capacity increases.

7 illus, 5 tables, 11 ref

012095   Khanra A K;Pathak L C;Godkhindi M M (Metallurgical and Materials Engineering Dep, National Institute of Technology, Warangal-506 004, Email: asit_iitkgp@yahoo.com) : Application of new tool material for electrical discharge machining (EDM). Bull Mater Sci 2009, 32(4), 401-5.

In EDM, Cu and graphite are commonly used as tool materials. The poor wear resistance is the drawback of these tools. In the current study, an attempt has been made to develop a ZrB₂-Cu composite as an EDM tool material to overcome this problem. Initially, the ZrB₂ powder is prepared by self-propagating high-temperature synthesis (SIIS) technique and synthesized powder is mixed with different amounts of Cu powder. Dense composite is developed by a pressureless sintering at 1250°C. The composites are tested as tool material at different EDM process parameters during machining of mild steel. The ZrB₂-40 wt% Cu composite shows highest metal removal rate (MRR) with significant tool removal rate (TRR) than other composites. The performance of ZrB₂-40 wt% Cu composite is compared to conventional Cu tool. The composite shows higher MRR with less TRR than Cu tool but it shows more average surface roughness and diameteral overcut than Cu tool.

10 illus, 10 ref

012094   Kazeminezhad M (Materials Science and Engineering Dep, Sharif Univ of Technology, Azadi Avenue, Tehran, Iran, Email: mkazemi@sharif.edu) : Modeling nano-scale grain growth of intermetallics. Bull Mater Sci 2009, 32(1), 19-21.

The Monte Carlo simulation is utilized to model the nano-scale grain growth of two nano-crystalline materials, Pd_8lZr₁₉ and RuAl. In this regard, the relationship between the real time and the time unit of simulation, i.e. Monte Carlo step (MCS), is determined. The results of modeling show that with increasing time of heating, the grain sizes of both nano-crystalline materials increased as in the ease of conventional materials. Moreover, it is found that for both nano-crystalline materials the relationship between the real time and MCS is in power law form, which is linear for the conventional materials.

4 illus, 2 tables, 10 ref

012093   Kashyap K T (Mechanical Engineering Dep, PES Institute of Technology, Bangalore-560 085, Email: ktkashyap@yahoo.com ) : Discontinuous precipitation in copper base alloys. Bull Mater Sci 2009, 32(4), 413-14.

Discontinuous precipitation (DP) is associated with grain boundary migration in the wake of which alternate plates of the precipitate and the depleted matrix form. Some copper base alloys show DP while others do not. In this paper the misfit strain parameter, η, has been calculated and predicted that if 100 η>±0-1, DP is observed. This criterion points to diffusional coherency strain theory to be the operative mechanism for DP.

2 tables, 6 ref

012092   Joshi B;Islam S S;Mavi H S;Kumari V;Islam T; Shukla A K;Harsh (Applied Sciences and Humanities Dep, Jamia Millia Islamia, Central Univ, New Delhi-110 025, Email: safiul_el@rediffmail.com ) : Wavelength dependent laser-induced etching of Cr-O doped GaAs: morphology studies by SEM and AFM. Bull Mater Sci 2009, 32(1), 31-5.

The laser induced etching of semi-insulating GaAs (100) is carried out to create porous structure under super- and sub-bandgap photon illumination (h v). The etching mechanism is different for these separate illuminations where defect states play the key role in making distinction between these two processes. Separate models are proposed for both the cases to explain the etching efficiency. It is observed that under sub-bandgap photon illumination the etching process starts vigorously through the mediation of intermediate defect states. The defect states initiate the pits formation and subsequently pore propagation occurs due to asymmetric electric field in the pore. Formation of GaAs nanostructures is observed using scanning electron (SEM) and atomic force microscopy (AFM).

6 illus, 13 ref

012091   Jiaxiang Y;Deyun X;Ludong J;Rui G (Automation Dep, Tsinghua Univ, Beijing-100 084) : New geo-location approach based on camera coordinates and common points on multiple images. Def Sci J 2009, 59(1), 43-8.

The accuracy of tradiiional unmanned aerial vehicle (UAV) geo-location based on single image is too low to meet the needs of precise strike. In this paper, a new UAV geo-location method is presented. The mathematical models are constructed by linearization of the collinearity equations to iterativcly compute the pose angles and focal length of the camera. At least three images of the target, along with at least three identifiable common points among the images, are needed for reckoning camera pose angles and focal length. The three dimensional (3D) coordinates of ground target are calculated using forward intersection. The new method can get the target coordinates with no dependence on digital elevation model (DEM) and the measured values of camera pose angles, therefore two of the three primary error sources in the traditional UAV target location approach are eliminated. Simulation and real image experiment results show that the accuracy of the estimated target location is close to that of the UAV position, and that target location error is within 5m circular error probable (CEP) on condition that the UAV is navigated by differential global positioning systems (DGPS).

3 illus, 17 ref

012090   Jagadeesha T;Kim L;Gonsalvis J;Gowda T (NO, SJEC, Mangalore, Email: jagdishsg@yahoo.com) : Correlation between wafer temperature and partice performance in a HDP - CVD FSG process. Natn J Technol 2009, 5(4), 1-4.

Investigates root cause for non-mechanical particle contamination of fluorinated oxide (FSG) films. It is shown that the wafer temperature at SiF₄ introduction and during process is a controlling factor for particle generation. If the wafer temperature is too low the doped oxide exhibits hazing. In some cases, the film appeared to be bubbled and even peeled off locally. If the wafer temperature is too high, the film is also hazy, particularly at the edge of the wafer. When the SiF₄ flows along with SiH₄ to the chamber within a specific range of wafer temperatures, we can deposit a nearly particle-free damascene FSG film in the 300mm High Density Plasma -Chemical Vaporization Deposition (HDP-CVD) chamber.

3 illus, 6 ref

012089   Jacob K T;Gupta S (Materials Engineering Dep, Indian Institute of Science, Bangalore-560 012, Email: katob@materials.iisc.ernet.in) : Phase diagram of the system Ca-Ti-O at 1200 K. Bull Mater Sci 2009, 32(6), 611-16.

Phase relations in the system Ca-Ti-O have been established by equilibration of several samples at 1200 K for prolonged periods and identification of phases in quenched samples by optical and scanning electron microscopy, XRD and EDS. Samples representing 20 compositions in the ternary system were analyzed. There was negligible solid solubility of Ca in the phases along the binary Ti-O, and of Ti in CaO. Four ternary oxides were identified: CaTiO₃, Ca₄Ti₃O₁₀ and Ca₄Ti₂O₇ containing tetravalent titanium, and CaTi₂O₄ containing trivalent titanium. Tie-lines link calcium titanite (CaTi₂O₄) with the three calcium titanates (CaTiO₃, Ca₄Ti₃O₁₀ and Ca₃Ti₂O₇), CaO, oxygen excess TiO_1+δ and stoichiometric TiO. Tie-lines connect CaTiO3 with TiO_2-x, Magneli phases Ti_nO_{2n_1} (28 ≥ n≥ 4), Ti₃O₅, Ti₃O₅ and TiO_1+δ. CaO was found to coexist with TiO, and Ti-O solid solutions a and β. The phase diagram is useful for understanding the mechanisms and kinetics of direct calciothermic reduction of TiO₂ to metal and electrochemical reduction of TiO₂ using graphite anode and molten CaCl₂ electrolyte.

2 illus, 2 tables, 17 ref

012088   Himanshu Shekhar H (NO, High Energy Materials Research Laboratory, Pune-411 021) : Design of funnel port tubular propellant grain for neutral burning profile in rockets. Def Sci J 2009, 59(5), 494-8.

Radial outward burning tubular propellant grain gives progressive burning profile, but trimming port at one end to conical form gives close to neutral burning profile. Though this configuration is easy to realize, but close-form burnback equation for performance prediction of such propellant geometry is not available. In this paper, close-form burnback equation for conically trimmed tubular propellant grain is developed. One propellant grain is also evaluated and performance matching to prediction by developed formulation is realised. Parametric study for different aspect ratio (L/D), diameter ratio (d/D) and slant angle (6) is carried out for a typical configuration and variation is explained. The developed formulation is simple, handy, easy and quick.

6 illus, 1 table, 6 ref