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Epigeal and Hypogeal Macroinvertebrate Diversity in Different Microhabitats of the Yusmarg Hill Resort (Kashmir, India)
Abroo Ali,G. A. Bhat,Mudasir Ali
Ecologia Balkanica , 2012,
Abstract: Soil macroinvertebrate communities are important within the soil system and contribute to a wide variety of soil processes. A soil study was conducted to assess the composition and diversity of soil macroinvertebrates in Yusmarg hill resort of Kashmir valley at four sites characterised by different types of vegetation and interferences like grazing or fencing, during the months of May, June, November and December 2010. During the study, it was observed that different sites exhibited variations in diversity of both epigeal as well as hypogeal soil macroinvertebrates. For epigeal macroinvertebrates, highest diversity was recorded in forest edge (2.089) and inner forest (2.058) and relatively low diversity in grazed (1.61) and fenced areas (1.09). For hypogeal macroinvertebrates, diversity was recorded highest for inner forest site (2.216) than forest edge (1.9) and relatively lower in fenced (1.22) and grazed (1.21) sites. The physical disturbance in the form of grazing and fencing probably reduce the diversity of the soil macro fauna as is inferred from the present study.
Ultrastructural Identification of the Basal-Granulated Cells in the Duodenum of Albino Rat  [PDF]
Ali Hassan A. Ali
Open Journal of Gastroenterology (OJGas) , 2014, DOI: 10.4236/ojgas.2014.47041
Abstract: The fine structure of the crypt epithelium of the duodenal mucosa in albino rats was studied to represent the types and distribution of the basal-granulated or endocrine cells. Twenty male animals were used. Perfusion-fixation was made and samples of duodenal mucosa were taken and processed to prepare epon-embedded specimens for examination by a transmission electron microscope. Cells containing membrane-bound granules were seen in the crypt epithelium. They were identified to be basal-granulated cells. Six different types of such cells were demonstrated. All of the cells were of the closed type. The possible functional significance of these closed cell types was discussed. Correlation among the distributions of such cells in the intestine of albino rat might enable the physiologists, internists and other research workers to study several biologically active peptides with well-established functions other than those which have long been investigated.
A Primal-Dual Simplex Algorithm for Solving Linear Programming Problems with Symmetric Trapezoidal Fuzzy Numbers  [PDF]
Ali Ebrahimnejad
Applied Mathematics (AM) , 2011, DOI: 10.4236/am.2011.26089
Abstract: Two existing methods for solving a class of fuzzy linear programming (FLP) problems involving symmetric trapezoidal fuzzy numbers without converting them to crisp linear programming problems are the fuzzy primal simplex method proposed by Ganesan and Veeramani [1] and the fuzzy dual simplex method proposed by Ebrahimnejad and Nasseri [2]. The former method is not applicable when a primal basic feasible solution is not easily at hand and the later method needs to an initial dual basic feasible solution. In this paper, we develop a novel approach namely the primal-dual simplex algorithm to overcome mentioned shortcomings. A numerical example is given to illustrate the proposed approach.
Application of Linear Model Predictive Control and Input-Output Linearization to Constrained Control of 3D Cable Robots  [PDF]
Ali Ghasemi
Modern Mechanical Engineering (MME) , 2011, DOI: 10.4236/mme.2011.12009
Abstract: Cable robots are structurally the same as parallel robots but with the basic difference that cables can only pull the platform and cannot push it. This feature makes control of cable robots a lot more challenging compared to parallel robots. This paper introduces a controller for cable robots under force constraint. The controller is based on input-output linearization and linear model predictive control. Performance of input-output linearizing (IOL) controllers suffers due to constraints on input and output variables. This problem is successfully tackled by augmenting IOL controllers with linear model predictive controller (LMPC). The effecttiveness of the proposed method is illustrated by numerical simulation.
A Study on Wear Resistance, Hardness and Impact Behaviour of Carburized Fe-Based Powder Metallurgy Parts for Automotive Applications  [PDF]
Ali Emamian
Materials Sciences and Applications (MSA) , 2012, DOI: 10.4236/msa.2012.38073
Abstract: In order to study the mechanical and triboloical properties of powder metallurgy (PM) parts under different process parameters, the specimens were used in pack carburizing processes. These specimens made from industrial test pieces were carburized in a powder pack for about two to five hours at a temperature of about 850?C - 950?C. The effects of austenitization and quenching are investigated on some specimens. Also the wear tests are performed by means of a pin-on-disc tribotester using roll bearing steel as the counterface material. The results indicate that by appropriate selection of process parameters, it is possible to obtain high wear resistance along with moderate toughness. It is concluded that surface treatments increases the wear resistance and performance of PM parts in service conditions. By increasing the role of PM in industry which resulted from their ability to produce the complex shapes, high production rate, and dimension accuracy of final products, they need to be heat treated. Carburizing method was selected as a surface hardening method for PM parts. Results of wear and hardness show considerable enhancement in mechanical properties of PM parts.
Influence of Ferric and Ferrous Iron on Chemical and Bacterial Leaching of Copper Flotation Concentrates  [PDF]
Ali Ahmadi
International Journal of Nonferrous Metallurgy (IJNM) , 2012, DOI: 10.4236/ijnm.2012.13006
Abstract: The effects of ferrous and ferric iron as well as redox potential on copper and iron extraction from the copper flotation concentrate of Sarcheshmeh, Kerman, Iran, were evaluated using shake flask leaching examinations. Experiments were carried out in the presence and absence of a mixed culture of moderately thermophile microorganisms at 50?C. Chemical leaching experiments were performed in the absence and presence of 0.15 M iron (ferric added medium, ferrous added medium and a mixture medium regulated at 420 mV, Pt. vs. Ag/AgCl). In addition, bioleaching experiments were carried out in the presence and absence of 0.1 M iron (ferric and ferrous added mediua) at pulp density 10% (w/v), inoculated bacteria 20% (v/v), initial pH 1.6, nutrient medium Norris and yeast extract addition 0.02% (w/w). Abiotic leaching tests showed that the addition of iron at low solution redox potentials significantly increased the rate and extent of copper dissolution but when ferric iron was added, despite a higher initial rate of copper dissolution, leaching process stopped. Addition of both ferrous and ferric iron to the bioleaching medium levelled off the copper extraction and had an inhibitory effect which decreased the final redox potential. The monitoring of ferrous iron, ferric iron and copper extraction in leach solutions gave helpful results to understand the behaviour of iron cations during chemical and bacterial leaching processes.
Nitrification of Reactively Magnetron Sputter Deposited Ti-Cu Nano-Composite Thin Films  [PDF]
Ali Rahmati
Soft Nanoscience Letters (SNL) , 2013, DOI: 10.4236/snl.2013.31004
Abstract:

A metalloid Ti13Cu87 target was sputtered by reactive DC magnetron sputtering at various substrate temperatures in an Ar-N2 mixture ambient. The sputtered species were condensed on Si (111), glass slide and Potsssium bromide (KBr) substrates. The as-deposited films were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), optical spectrophotometry and four point probe technique. The as-deposited films present composite structure of nano-crystallite cubic anti-ReO3 structure of Ti inserted Cu3N (Ti:Cu3N) and nano-crystallite face centre cubic (fcc) structure of Cu. The titanium atoms and sequential nitrogen excess form a solid solution within the Cu3N crystal structure and accommodate in crystal lattice and vacant interstitial site, respectively. Depending on substrate temperature, unreacted N atoms interdiffuse between crystallites and their (and grain) boundaries. The films have agglomerated structure with atomic Ti:Cu ratio less than that of the original targets. A theoretical model has been developed, based on sputtering yield, to predict the atomic Ti:Cu ratio for the as-deposited films. Film thickness, refractive index and extinction coefficient are extracted from the measured transmittance spectra. The films’ resistivity is strongly depending on its microstructural features and substrate temperature.

An Automata-Based Approach to Pattern Matching  [PDF]
Ali Sever
Intelligent Control and Automation (ICA) , 2013, DOI: 10.4236/ica.2013.43036
Abstract: Due to its importance in security, syntax analysis has found usage in many high-level programming languages. The Lisp language has its share of operations for evaluating regular expressions, but native parsing of Lisp code in this way is unsupported. Matching on lists requires a significantly more complicated model, with a different programmatic approach than that of string matching. This work presents a new automata-based approach centered on a set of functions and macros for identifying sequences of Lisp S-expressions using finite tree automata. The objective is to test that a given list is an element of a given tree language. We use a macro that takes a grammar and generates a function that reads off the leaves of a tree and tries to parse them as a string in a context-free language. The experimental results indicate that this approach is a viable tool for parsing Lisp lists and expressions in the abstract interpretation framework
On the Numerical Solutions of One and Two-Stage Model of Carcinogenesis Mutations with Time Delay and Diffusion  [PDF]
Ishtiaq Ali
Applied Mathematics (AM) , 2013, DOI: 10.4236/am.2013.410A2012
Abstract:

In this paper, we focused on numerical solutions of carcinogenesis mutations models that are based on reaction-diffusion systems and Lotka-Volterra food chains. We consider the case with one and two-stages of mutations with appropriate initial conditions and the zero-flux boundary conditions. The main purpose is to construct a stable discretization scheme, which allows much accuracy than those of a standard approach. To this end, we use the spectral method to postprocess numerical solutions for the proposed model by using some classical methods for solving differential equations. The implementation of the algorithm is simple and it does not need to solve the linear or nonlinear system (in case the model is nonlinear). We simulate the one and two-stage carcinogenesis mutations model and compared the results with previously published ones.

On (2, 3, t)-Generations for the Rudvalis Group Ru  [PDF]
Faryad Ali
Applied Mathematics (AM) , 2013, DOI: 10.4236/am.2013.49174
Abstract:

A group G is said to be(2,3,t) -generated if it can be generated by an involution x and an element y so that 0(y)=3 and 0(xy)=t. In the present article, we determine all (2,3,t)-generations for the Rudvalis sporadic simple group Ru, where t is any divisor of \"\".

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