August 2010
The solution of the real scalar field in SdS and RNdS spaces
In this letter, several works about the solutions of the real scalar field in SdS and RNdS are compared. Some previous works gave out that the wave amplitude near the potential peak is harmonic versus the radius, some gave out the wave amplitude near the potential peak increases, and others showed contrary results. By a simple mathematical calculation, here we unite the aforementioned results and denote that the wave...
August 2010
Sand water storage systems using coefficient of uniformity as surrogate for optimal design : A laboratory study
Uneven surfaces of sand particles provide ideal opportunities, under arid conditions, for runoff to be stored in the voids of sandy riverbed of ephemeral river. Series of laboratory experiments were performed to study major controlling parameters of sedimentation in sand water storage in order to optimize storage potential. Analysis was based on coefficient of uniformity of grain size distributions of deposited...
August 2010
Comparison of mechanical and bond properties of oil palm kernel shell concrete with normal weight concrete
The comparison of the fresh, mechanical and bond properties of grade 30 lightweight concrete, namely oil palm kernel shell concrete (OPKSC) with normal weight concrete (NWC) of similar strength is presented in this paper. Oil palm kernel shell (OPKS), an industrial waste has been used as lightweight aggregates (LWA) in the OPKSC. In addition, mineral admixtures, 10% of silica fume and 5% fly ash have been used. The...
August 2010
A comparison of horizontal roughing filters and vertical roughing filters in wastewater treatment using gravel as a filter media
Roughing filtration can be considered as a major pretreatment process for waste water, since the process efficiently separate fine solid particles over prolonged periods without addition of chemicals. Roughing filters mainly act as physical filters and reduce the solid mass. However, the large filter surface area available for sedimentation and relatively small filtration rates also supports adsorption as well as...
August 2010
Presence enabled conditional call setup model for IP multimedia subsystem
IP multimedia subsystem (IMS) provides the architectural framework for next generation networks. Presence is considered as the most important service of IMS. Currently, a user needs to subscribe for the presence service of the receiver before deciding whether to call that particular receiver or not. This mechanism increases the network traffic and may result in more delay in call setup. To handle this problem, we...
August 2010
Mesogenic azomethine esters with different end groups: Synthesis and thermotropic properties
Series of elongated azomethine esters containing two aromatic rings with stearoyl moiety as one of the terminal carbon chain and various substituents X (where X = H, F, Cl, Br, OCH3, CH3 and C2H5) at the other end of molecule have been isolated and their structures were proposed via physical measurement. The mesomorphic properties of these compounds were investigated via differential scanning calorimetry and...
August 2010
Synthesis and characterization of organotin(IV) complexes derived of 4-(diethylamino) benzoic acid: In vitro antibacterial screening activity
Four organotin(IV) carboxylate complexes derivative of 4-(diethylamino)benzoic acid have been successfully synthesized and characterized quantitatively and qualitatively. The complexes obtained are screened for their in vitro antibacterial screening activity. Monomeric {4-[N(C2H5)2]C6H4COO}2(R)2Sn (R = methyl 1, butyl 2), [{4-[N(C2H5)2]C6H4COO(C4H9)2Sn}2O]2 dimer 3 and...
August 2010
Equilibrium studies for the removal of basic dye by sunflower seed husk (Helianthus annuus)
The sorption characteristics of sunflower (Helianthus annuus) seed husk (SSH) to remove Methylene Blue (MB) from aqueous solution under batch conditions have been investigated. Sorption of MB was found to be pH, concentration and agitation dependent. The kinetics of sorption was rapid with 80% sorption taking place within the first 60 min regardless of its initial concentration. The fast attainment of equilibrium...
August 2010
A one-way dissection of high-order compact scheme for the solution of 2D Poisson equation
We present a one-way dissection formulation of high-order compact scheme for the solution of 2D Poisson equation. One-way dissection is a type of matrix reordering, divide and conquers procedure. Efficient and concise compact schemes of 4th and 6th orders are derived using the truncation errors of the Taylors’ series expansion of the governing equation. The system is split into sub-domains and each sub-domain is...
August 2010
Construction of the Frenet-Serret frame of a curve in 4D Galilean space and some applications
In this work, first, we construct Frenet-Serret frame of a curve in the Galilean 4-space. As a result of this, we obtain the mentioned curve’s Frenet-Serret equations. Then, we prove that tangent vector of a curve in Galilean 4-space satisfies a vector differential equation of fourth order. Additionally, some characterizations of Galilean spherical curves and an example of the main results are...
August 2010
Improving multiplication and reminder using implementation based on word and index
Asynchronous cryptography is one of the most widely used cryptographic algorithms. Much research has been done to find other applications of this cryptography method. Modular exponentiation is one of the primitive operations in these algorithms. Since we need to perform multiplication, square and modular division, most aspects of these studies were based on optimizing each of these algorithms. Since access to faster...
August 2010
Linking the balanced scorecard (BSC) to business management performance: A preliminary concept of fit theory for navigation science and management
Natural oceanic phenomenon, such as internal waves and ocean currents, produce rapid environmental changes which can disrupt ocean-going mass transportation and shipping. The purpose of this study is to examine the relationship between ocean-induced environmental uncertainties and navigational business performance. A number of technical models, both numerical, regression and phenomenological, have already been...
August 2010
Characterization of groundwater chemistry in the coastal plain-sand aquifer of Owerri using factor analysis
Groundwater is a valuable natural resource for various human activities. Factor analysis was applied to the hydrochemical data from the coastal plain-sand (Benin Formation) aquifers of Owerri in order to extract the principal factors responsible for the different hydrochemical facies. By using Kaiser Normalization, the principal factors were extracted from the data. The analysis reveals five sources of solutes. The...
August 2010
Calculation and analysis of pore vapor pressure of concrete exposed to fire
The present work involves calculation and analysis of pore vapor pressure in high strength concrete (HSC) exposed to fire. In order to study the spalling of high strength concrete exposed to fire, a mathematical model of the coupled actions of hydro-thermal effects is established. The temperature field and the pressure field are calculated at a given temperature. Then, the pore vapor pressure is calculated and analyzed...
August 2010
Observation of the students’ “earthquake†perceptions by means of phenomenographic analysis (primary education 7th grade – Turkey)
The purpose of this research is to define and explain how 7th grade students’ in Turkey perceive “earthquake” concept using phenomenographic research methods. The research group of the study is comprised of 553 7th grade students in four cities (Ankara, Adana, Antalya and Karabük) in Turkey. The data of the research was gathered by students’ completing “I...
Advertisement
Advertisement
