Showing papers by "Thapar University published in 2008"
TL;DR: The effect of recycled and waste plastic on bulk density, air content, workability, compressive strength, splitting tensile strength, modulus of elasticity, impact resistance, permeability, and abrasion resistance is discussed in this paper.
804 citations
TL;DR: Five aerobic consortia capable of degrading chlorpyrifos as a sole carbon source in aqueous medium showed degradation in the range of 46–72% after 20 days, while population dynamics of the introduced isolates based on antibiotic resistance survival and REP-PCR indicated 60–70% survival based on antibiotics resistance, but only 35–45% of the inoculated population based on REP -PCR.
122 citations
TL;DR: In this paper, the authors present an overview of some of the research published on the use of SFS in controlled low-strength materials and concrete, including concrete properties such as compressive strength, splitting tensile strength, modulus of elasticity, freezing-thawing resistance and shrinkage.
Abstract: With ever increasing quantities of industrial by-products and waste materials, solid waste management has become the principal environmental concerns in the world. Scarcity of land-filling space and due to its ever increasing cost, utilization/recycling of by-products/waste has become an attractive alternative to disposal. Several types of by-products and waste materials are generated. Each of these waste products has specific effects on the properties of cement-based materials (CLSM and Concrete). The utilization of such materials in concrete/CLSM not only makes it economical, but also do help in reducing disposal problems. Reuse of bulk wastes is considered the best environmental alternative for solving the problem of disposal. One of such industrial by-products is Spent Foundry Sand (SFS). Spent foundry sand is a by-product of ferrous and non-ferrous metal casting industries. Foundries successfully recycle and reuse the sand many times in a foundry. When the sand can no longer be reused in the foundry, it is removed from the foundry and is termed as spent foundry sand. Published literature has shown that SFS could be possibly used in manufacturing Controlled Low-Strength Materials (CLSM) and concrete. This paper presents an overview of some of the research published on the use of SFS in controlled low-strength materials and concrete. Effect of SFS on CLSM characteristics like plastic properties, compressive strength, permeability, and leachate analysis, and concrete properties such as compressive strength, splitting tensile strength, modulus of elasticity, freezing–thawing resistance, and shrinkage are presented.
121 citations
TL;DR: Among the three mixed bacterial culture AE, BE, and CE, developed by enrichment technique with endosulfan as sole carbon source, consortium CE was found to be the most efficient with 72% and 87% degradation of alpha-endosolfan and beta-endOSulfan, respectively, in 20 days.
94 citations
27 May 2008
TL;DR: In this article, an elastic matching technique was used to recognize online handwritten Gurmukhi characters, which achieved a 90.08% recognition rate for 60 writer's and 41 characters.
Abstract: This paper presents implementation of elastic matching technique to recognize online handwritten Gurmukhi characters. We have discussed a process that recognizes characters in two stages. First stage recognizes the strokes, in second stage, character is evaluated on the basis of recognized strokes. Feature are computed to strengthen recognition results. Also, we have discussed a simple way to store data for handwritten strokes and characters. The database for strokes stores script number, stroke number and stroke sample number for every point of a stroke. For 60 writer's and a set of 41 Gurmukhi characters, we have obtained recognition rate as 90.08%.
79 citations
TL;DR: In this paper, a series of SiO 2 -B 2 O 3 -MgO/SrO / SrO glasses of different compositions were prepared by taking appropriate proportion (mol%) of each oxide constituents followed by mixing and melting in alumina crucible at 1550 ∘ C The molten glasses were quenched in air.
73 citations
TL;DR: The enzyme activities such as acid phosphatase and phytase increased significantly in mutants compared to the wild type and suggested the role of these enzymes in P solubilization apart from the organic acid exudation and H+ pump in A. tubingensis.
Abstract: The mechanisms of action of phosphate solubilization were studied in the wild-type strain Aspergillus tubingensis and the phenotypic mutants derived from it. The P solubilization activities of these isolates were measured in liquid media using different carbon and nitrogen sources. All the mutants showed higher P solubilization compared to the wild type. Glucose and sucrose significantly promoted P solubilization compared to fructose, lactose, galactose, and xylose. Potassium nitrate significantly increased P solubilization compared to other nitrogen sources such as ammonium sulfate, ammonium nitrate, aspargine, and tryptophan. The P solubilization activity was strongly associated with the production of organic acids, especially succinic acid and acetic acid. The enzyme activities such as acid phosphatase and phytase also increased significantly in mutants compared to the wild type. These results suggested the role of these enzymes in P solubilization apart from the organic acid exudation and H+ pump in A. tubingensis.
71 citations
TL;DR: This paper surveys a number of quality models for traditional and component-based systems and proposes a new model for CBS by proposing some new characteristics, which may be very relevant in the context of components, by using Analytical Hierarchy Process.
Abstract: Component-Based Development (CBD) approach now is widely accepted in software industry. This approach enables efficient application development through the integration of already developed software components. The success of these applications heavily depends upon the selection of appropriate components to fit customer requirements. Therefore it is very necessary to evaluate the quality of components before using them in the final system. Quality models proposed so far can not be fully implemented as-it-is on components and component-based systems (CBS) due to architectural differences in the development approach. Present paper surveys a number of quality models for traditional and component-based systems and proposes a new model for CBS by proposing some new characteristics, which may be very relevant in the context of components. All the quality characteristics may not be of prime importance for an application to be developed for a specific domain. Therefore, it is necessary to identify only those characteristics/sub-characteristics, which may have higher priorities over the others. The present work uses Analytical Hierarchy Process (AHP) to assign the weight values to the characteristics for the proposed model. These weight values are then used to evaluate the quality contribution of sub-characteristics, characteristics and then finally the overall quality of the component by using the appropriate metrics. This approach can be used to identify and select better quality component among several others which can be used in the final system.
71 citations
TL;DR: In this article, a new series of Bi4V2−x Alx O11− (0 x 04) samples were prepared by taking an appropriate amount of constituent oxides The sintered pellets were characterized by a scanning electron microscope (SEM) and an X-ray diffraction (XRD) technique.
59 citations
TL;DR: Mn-doped ZnS nanoparticles, having average diameter 3-5 nm, have been synthesized using chemical precipitation technique without using any external capping agent Zinc blende crystal structure has been confirmed using the X-ray diffraction studies as mentioned in this paper.
Abstract: Mn-doped ZnS nanoparticles, having average diameter 3–5 nm, have been synthesized using chemical precipitation technique without using any external capping agent Zinc blende crystal structure has been confirmed using the X-ray diffraction studies The effect of various concentrations of Mn doping on the photoluminescent properties of ZnS nanoparticles has been studied The time-resolved photoluminescence spectra of the ZnS:Mn quantum dots have been recorded and various parameters like lifetimes, trap depths, and decay constant have been calculated from the decay curves at room temperature The band gap was calculated using UV–Visible absorption spectra
57 citations
TL;DR: In this article, a glass of composition 40SiO2−30BaO−20ZnO−10B2O3 was made by conventional melting and casting process.
Abstract: Glass of composition 40SiO2–30BaO–20ZnO–10B2O3 (mol%) was made by conventional melting and casting process. Crystallization kinetics of above glass has been investigated under non-isothermal conditions, using the formal theory of transformations for heterogeneous nucleation. The procedure is applied to the experimental data obtained by differential thermal analysis (DTA), using continuous-heating techniques. The crystallization results are analyzed, and both the activation energy of crystallization process as well as the crystallization mechanism is characterized. Dilatometric measurement of this glass was also done and data obtained was used to calculate the viscosity of the formed glass. Development of crystalline phases on thermal treatments of the glass at various temperatures has been analyzed by X-ray diffraction. Microstructure of the crystalline phases was investigated by scanning electron microscopy (SEM) and the development of various structural features with variation in heat treatment cycle was observed. The nucleation and growth of these phases in the matrix of glass has been described and discussed.
TL;DR: The Weibull distribution model provided a good description of the kinetics of inactivation of peroxidase in mint leaves over the selected temperatures, and the temperature dependence of parameters and distribution curve characteristics were determined.
TL;DR: In this article, a review on the problems encountered in machining titanium and application of USM was presented, which has been concluded that all factors have significant effect on Material Removal Rate (MRR), Tool Wear Rate (TWR), and surface roughness of the machined surface.
Abstract: This paper presents a review on the problems encountered in machining titanium and application of USM in machining titanium and its alloys. Experiments have been conducted to assess the effect of three factors-tool material, grit size of the abrasive slurry and power rating of ultrasonic machine on machining characteristics of titanium (ASTM Grade I) using full factorial approach for design and analysis of experiments. It has been concluded that all factors have significant effect on Material Removal Rate (MRR), Tool Wear Rate (TWR) and surface roughness of the machined surface. Two-way interactions having significant effect on MRR, TWR and surface roughness have also been identified using Minitab14 software. The levels for each factor that contribute the most to the variation in machining performance of USM of titanium have also been established. It has been concluded that titanium is fairly machinable with USM process. Moreover, the surface finish obtained is better than many of the other non-traditional processes.
TL;DR: In this paper, the role of system size and momentum dependent effects in multifragmenation was analyzed by simulating symmetric reactions of symmetric reaction with incident energies between 50 and 1000 MeV/nucleon and over full impact parameter zones, and it was shown that there exists a system size dependence when the reaction is simulated with momentum dependent interactions.
Abstract: The role of system size and momentum dependent effects are analyzed in multifragmenation by simulating symmetric reactions of $\mathrm{Ca}+\mathrm{Ca}$, $\mathrm{Ni}+\mathrm{Ni}$, $\mathrm{Nb}+\mathrm{Nb}$, $\mathrm{Xe}+\mathrm{Xe}$, $\mathrm{Er}+\mathrm{Er}$, $\mathrm{Au}+\mathrm{Au}$, and $\mathrm{U}+\mathrm{U}$ at incident energies between 50 MeV/nucleon and 1000 MeV/nucleon and over full impact parameter zones. Our detailed study reveals that there exists a system size dependence when the reaction is simulated with momentum dependent interactions. This dependence exhibits a mass power law behavior.
TL;DR: In this paper, the effects of gamma ray irradiation and glass composition on the optical and infrared spectra of quaternary silicate glasses were investigated and the formation of radiation-induced absorption bands in the visible region attributed to nonbridging oxygen hole centres was revealed.
Abstract: This paper reports the effects of gamma ray irradiation and glass composition on the optical and infrared spectra of quaternary silicate glasses. Experimental results reveal the formation of radiation-induced absorption bands in the visible region attributed to nonbridging oxygen hole centres. The band gap energy and the width of the energy tail above the mobility gap have been measured before and after irradiation. The decrease in the energy gap values has been discussed in terms of radiation-induced structural modifications and the glass composition. Changes in the infrared spectra with progressive gamma irradiation have been observed and explained with reference to the radiolysis of Si–O–Si bonds.
TL;DR: In this article, the authors reported on differential thermal analysis (DTA) and dilatometric studies to characterize the thermal stability, kinetics and crystallization processes of a glass with composition 30BaO−20ZnO−2.5Al 2 O 3 −40SiO 2 (mol%) (designated as BZAS).
Abstract: We report on differential thermal analysis (DTA) and dilatometric studies to characterize the thermal stability, kinetics and crystallization processes of a glass with composition 30BaO–20ZnO–2.5Al 2 O 3 –7.5B 2 O 3 –40SiO 2 (mol%) (designated as BZAS). The empirical relation between the viscosity of the glass with temperature was calculated by employing the Vogel–Fulcher–Tamman (VFT) equation. Crystallization kinetics was determined under non-isothermal conditions, using the formal theory of transformations for heterogeneous nucleation. The experimentally determined crystallization kinetics was fit to calculate the activation energy for crystallization. Development of crystalline phases on thermal treatments of the glass at various temperatures has been followed by X-ray diffraction (XRD). Microstructure and chemical composition of the crystalline phases were investigated by scanning electron microscopy (SEM) and energy-dispersive spectroscopic (EDS) analysis. Our results suggest that BZAS glass is a thermodynamically stable glass and is derived from a kinetically strong glass-forming liquid. DTA crystallization curve is formed by the overlapping of two exothermic crystallization curves designating two predominant phases, barium aluminum silicate and barium zinc silicate, as revealed by XRD, with activation energies for crystallization of 243 and 195 kJ/mol, and calculated values of Avrami constant of 2.05 and 3.07, respectively. However, it is difficult to confirm which of these two phases is first formed as both seem to appear simultaneously.
TL;DR: In this paper, the velocity and turbulence characteristics in an evolving scour hole downstream of an apron due to submerged jets issuing from a sluice opening detected by an acoustic Doppler velocimeter were investigated.
Abstract: This paper reports an experimental investigation on the velocity and turbulence characteristics in an evolving scour hole downstream of an apron due to submerged jets issuing from a sluice opening detected by an acoustic Doppler velocimeter. Experiments were carried out for the conditions of submerged jets, having submergence factors from 0.96 to 1.85 and jet Froude numbers from 2.58 to 4.87, over sediment beds downstream of a rigid apron. The distributions of time-averaged velocity vectors, turbulence intensities, and Reynolds stress at different streamwise distances are plotted for the conditions of initial flat bed, intermediate scour holes, and equilibrium scour hole downstream of an apron. Vector plots of the flow field show that the rate of decay of the submerged jet velocity increases with an increase in scour hole dimension. The bed-shear stresses are determined from the Reynolds stress distributions. The flow characteristics in evolving scour holes are analyzed in the context of self-preservation, growth of the length scale, and decay of the velocity and turbulence characteristics scales. The most significant observation is that the flow in the scour holes (intermediate and equilibrium) is found to be plausibly self-preserving.
TL;DR: In this paper, an exploratory study of North Indian medium and large-scale manufacturing organizations, which are in the process of achieving manufacturing flexibility at various levels by acquiring, developing or utilising AMT or by the use of specific sourcing practice, was conducted.
Abstract: Manufacturing flexibility is widely recognised as a critical component to achieving a competitive advantage in the marketplace and improves an organisation's capability to respond to customer demands without incurring excessive time and cost penalties. The objective of this paper is to understand and explicate the interaction between Advanced Manufacturing Technology (AMT) sourcing practices and manufacturing flexibilities at tactical and strategic levels and assess the first two's relative impact on different flexibilities. This research reports the findings of an exploratory study of North Indian medium- and large-scale manufacturing organisations, which are in the process of achieving manufacturing flexibilities at various levels by acquiring, developing or utilising AMT or by the use of specific sourcing practice. The statistical results suggest significant relationships between sourcing practises and manufacturing flexibilities at different levels of manufacturing flexibility. The results also suggest that an organisation could deploy specific sourcing practices or AMTs to target specific manufacturing flexibilities in pursuit of agility-based competitive advantages.
TL;DR: In this paper, the effect of increase in signal input power for the three power compensation methods is compared in terms of eye diagram, bit error rate, eye closure penalty and output received power.
TL;DR: This paper analyses some of existing Approaches for Resource Discovery, which can search for the preferred resources quickly and efficiently (return the correct results quickly and reduce network complexity) in Grid computing.
Abstract: Grid technologies enable the sharing of a wide variety of distributed resources. To utilize these resources, effective Resource Management systems are needed. Resource Management system performs resource discovery to obtain information about the available resources. However, the complex and dynamic nature of grid resources make sharing and discovery, a challenging issue. Resource Discovery is initiated by a network application to find suitable resources with in the Grid. Resource Discovery process is critical for efficient resource allocation and management. For making the Resource Discovery more efficient and reliable large numbers of Approaches are there. This paper analyses some of existing Approaches for Resource Discovery, which can search for the preferred resources quickly and efficiently (return the correct results quickly and reduce network complexity) in Grid computing. Finally a qualitative comparison between these Approaches based on the factors that affect Grid Resource Discovery process, has been done and results are presented.
TL;DR: This is the first report of isolated and characterized a xylanolytic actinomycete strain from the extremely alkaline bauxite residue obtained from National Aluminum Company Ltd., Damanjodi, India and offers a new source of xylanase-producing strains.
Abstract: We have isolated and characterized a xylanolytic actinomycete strain (RM1) from the extremely alkaline bauxite residue obtained from National Aluminum Company Ltd., Damanjodi, India. The phenotypic features and complete sequence of 16S rRNA revealed that this strain belong the genus Kocuria and showed 98% sequence similarity with Kocuria aegyptia. The RM1 strain was able to grow at pH 10.5 in buffered and unbuffered media and utilize 40 different carbon substrates. The RM1 strain under optimal conditions produced extracellular xylanase at 311 U/ml. The xylanase produced by RM1 showed a wide range of temperature (30–85°C) and pH (4.5–9) tolerance by retaining 90% of its activity. This is the first report of isolation of actinomycetes, Kocuria sp., which produces high amount of xylanase, from bauxite residue and offers a new source of xylanase-producing strains.
TL;DR: Wolfe and Mond-Weir type second-order symmetric duals are formulated and appropriate duality theorems are established under @h-bonvexity/@h-pseudobonvexy assumptions as mentioned in this paper.
TL;DR: Through simulations, it shows that a decrease in burst loss probability, cost effectiveness and a gain in processing time are obtained when optical label processing is used as compared with electronic processing.
Abstract: A novel optical burst switching (OBS) high speed network architecture has been proposed. To verify its feasibility and evaluate its performance, just-enough-time (JET) signaling has been considered as a high performance protocol. In the proposed architecture, to avoid burst losses, firstly, a short-prior-confirmation-packet (SPCP) is sent over the control channel that simulates the events that the actual packet will experience. Once SPCP detects a drop at any of the intermediate nodes, the actual packet is not sent but the process repeats. In order to increase network utilization, cost effectiveness and to overcome some limitations of conventional OBS, inherent codes (e.g., orthogonal optical codes (OOC)), which are codified only in intensity, has been used. Through simulations, it shows that a decrease in burst loss probability, cost effectiveness and a gain in processing time are obtained when optical label processing is used as compared with electronic processing.
TL;DR: In this paper, a three phase multistage mathematical model for exiting gas composition of rice husk in fluidized bed has been derived, which is based on three-phase theory of fluidization and material balance for shrinking rice hulls particles and is similar to model developed by Kunii and Levenspiel.
TL;DR: A generic changeability assessment technique that takes into account two well known fami-lies of available AOP languages viz, AspectJ and CaesarJ is defined and shows that highly dependent AO systems will absorb low changeability.
Abstract: Maintenance of software systems has become a major concern for software developers and users. In environments, where software changes are frequently required to improve software quality, chan-geability is an important characteristic of maintainability in ISO/IEC 9126 quality standards. Many researchers and practition-ers have proposed changeability assessment techniques for Object-Oriented Programming (OOP) and Aspect-Oriented Programming (AOP). To the best of our knowledge, no one has proposed chan-geability assessment technique for generic Aspect-Oriented (AO) Systems. AOP is an emerging technique that provides a means to clearly encapsulate and implement aspects that crosscut other modules. In this paper, we have defined a generic changeability assessment technique that takes into account two well known fami-lies of available AOP languages viz, AspectJ and CaesarJ. A co-relation analysis between changeability and dependency has been performed. Result shows that highly dependent AO systems will absorb low changeability.
TL;DR: In this article, an experimental investigation was carried out to evaluate the flow characteristics of refrigerant R-134a through an adiabatic helically coiled capillary tube.
Abstract: An experimental investigation was carried out to evaluate the flow characteristics of refrigerant R-134a through an adiabatic helically coiled capillary tube. The effect of various physical parameters like diameter and length of capillary tube, coil pitch, and inlet subcooling on the mass flow rate of R-134a was investigated. Moreover, the refrigerant mass flow rate through an instrumented capillary tube was also compared to that through a noninstrumented capillary tube. It was found that the provision of taps for pressure measurement on the capillary tube surface has a negligible effect on the mass flow rate of R-134a. Further, the coil pitch had a significant effect on the performance of the adiabatic helically coiled capillary tube. It was established that the coil pitch significantly influenced the mass flow rate through the adiabatic helically coiled capillary tube. It was concluded that the effect of coiling of the capillary tube reduces the mass flow rate by 5% to 15%, as compared to those of the s...
TL;DR: A liquid membrane based Zn2+ ion selective electrode containing N, N′-Bis(2-dimethylaminoethyl)-N,N′-dimethyl-9,10 anthracenedimethanamine (Bis (TMEDA) anthracene) (I) as ionophore has been prepared and characterized as mentioned in this paper.
TL;DR: In this paper, the degradation mechanism for hygrothermal aging of woven carbon-epoxy and woven glass-poxy composite laminates was investigated in the micro-scale.
Abstract: The degradation mechanism for hygrothermal aging of woven carbon-epoxy and woven glass-epoxy composite laminates was investigated in the micro-scale. Interlaminar shear and cross laminar flexural tests were performed on notched and unnotched specimens to know the mechanical performance of the composite laminates. The Interlaminar Shear Stress (ISS) for both the composites was also evaluated and correlated with the number of hygrothermal cycles. Four-point bending and tensile or compression shear loading configurations were also used. The stress at the onset of delamination (Delamination Damage Tolerance, DDT) was identified from the load-deflection curve of the flexural specimens and correlated with the number of hygrothermal cycles. It was found that both the ISS and DDT decrease with the exposure time. Dimensional stability was almost unchanged throughout the aging process, although there was a very little moisture absorption (∼1.3%) in glass-epoxy and carbon-epoxy composite laminates. SEM photomicrographs of the delaminated surface show that failure occurs suddenly in a macroscopically brittle mode by crack initiation and propagation method. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers.
TL;DR: In this article, a high-energy planetary ball mill with tungsten carbide jar and ball was used to prepare strontium hexaferrite powder and the magnetic properties were measured by Pulse magneto meter.
Abstract: In the present investigation celestite (natural ore of strontium) and blue dust (iron ore fines) have been used for the preparation of strontium hexaferrite powder. The mechanical alloying process has been adopted to prepare strontium hexaferrite powder. The celestite after chemical upradation and physically upgraded blue dust alongwith sodium carbonate was taken for the preparation of strontium hexaferrite in this experiment. The high-energy planetary ball mill with tungsten carbide jar and ball was used to prepare strontium hexaferrite powder. A long time of ball milling for different duration has led to displacement solid-state reaction. At the end of each experiment the product was washed thoroughly and dried. The X-ray diffaction study after annealing shows the development of single-phase strontium hexaferrite after 40 hrs. of milling. The resultant powder was compacted under magnetic field and sintered to prepare the magnet after annealing the ferrite powder. The magnetic properties were measured by Pulse magneto meter. The moderate value of coercivity, remanence and energy product were observed in this sintered magnet. The work illustrates the feasibility to prepare strontium hexaferrite magnetic powders directly from natural ores which can reduce the total cost of production as compared to conventional method.