Showing papers by "Jordan University of Science and Technology published in 1987"

Effect of Piracetam on electrocorticogram and local cerebral glucose utilization in the rat.

Abstract: 1. 1. The effect of Piracetam on hypoxia-induced alterations of cerebral cortex electrogenesis is studied. The results showed protection. 2. 2. As this anti-hypoxidotic property could be linked to Piracetam influence on energy-metabolic processes in the brain, we studied the effect of this nootropic drug on local cerebral glucose utilization (LCGU) by means of a variant of the Sokoloff's technique. 3. 3. Our results showed that Piracetam enhances LCGU. 4. 4. We suggest that both effects, the functional and the metabolic one, are related.

Fishing line connecting system and method of connecting a fishing line to a lure or weight to be moved through the water and components of such a system

Abstract: A fishing system in which removable line connectors can be attached to a lure that is to be pulled through the water to attract a fish. The connectors can be connected to the lure in various ways. The heads of the connectors are preferably eccentrically mounted on a stem of the connectors so that the fishing line, when threaded through the head, will have a different pull angle, depending on the orientation of the head in the lure. The connectors are ideally used with a lure having a bend and a twist and a distinct forward and rear end. The connectors can be removed and repositioned on this type of lure to change the action of the lure through the water. The invention includes a method of removing and reinstalling these lures to change the action. Various additional attachments can be provided in combination wiht the connectors. The invention includes apparatus for changing weights using connectors.

High performance liquid chromatographic analysis of cephalexin in serum and urine.

Abstract: A rapid, highly sensitive high performance liquid chromatographic method has been developed for the determination of cephalexin in serum and urine. Serum protein was precipitated with 1% zinc sulphate solution containing cephradine as the internal standard. The drugs were eluted from a 5 micron, C-18 reversed-phase column at ambient temperature with a mobile phase consisting of acetonitrile-methanol-acetate buffer of pH 4.2 (10:10:80%), at a flow rate of 1.4 ml/min with ultraviolet detection at 254 nm. Each analysis lasted 9 min. Quantification was achieved by the measurement of the peak-height ratio and the relative and absolute recoveries varied from 98 to 103%. Detection limits for cephalexin were 1 microgram/ml in serum and 5 micrograms/ml in urine. Within-run coefficient of variation ranged from 0.73 to 5.63% at three different concentrations for the serum and urine assay.

High Pressure Liquid Chromatographic Analysis of Orphenadrine Citrate and Acetaminophen in Pharmaceutical Dosage Forms

Abstract: An ion pair reversed phase high pressure liquid chromatographic method for the analysis of orphenadrine citrate (I) and acetaminophen (II) was developed. The mobile phase consisted of 20mM sodium-1-octane sulfonate in 50mM phosphate buffer (pH=3.0), mixed with 22.5% organic solvents (50:50, acetonitrile: methanol). The method is simple, reliable and could be adapted for quality control purposes.

Time-optimal output regulators for linear multivariable discrete-time systems Part 1. Right invertible decouplable systems

Abstract: Corsetti and Houpis (1985) presented a simple algebraic solution for the timeoptimal output regulator problem. This solution has been obtained for a special class of right invertible decouplable systems S(A, B, C) satisfying the condition that CB is of full rank. In this paper a general method is presented to extend the results of Corsetti and Houpis to all classes of right invertible decouplable systems S(A, B, C, E). It is shown that a simple state feedback control law drives each output of S(A, B, C, E) in a minimum number of steps equal to the order of the associated infinite zero. This state feedback represents the optimal solution for the considered time-optimal output regulator problem. A class of optimal solutions, parametrized by a free parameter matrix K, is obtained for non-square systems. The properties of the resulting optimal closed-loop system is given and a numerical example is worked out to illustrate the generality and feasibility of the proposed method.

New triangular finite element for plates and shells

Abstract: A new triangular shell finite element ‘TNTE.1’ (Ten Node Triangular Element, Model 1) is presented. The formulation is based on Sanders' theory which involves the inclusion of the normal rotation Φn in the bending‐strain relations only. The element displacement functions are complete cubic polynomials for inplane displacements u and v. For out‐of‐plane displacement w, three new singular rational shape functions were added at the element corners. Thus a conforming triangular element with twenty seven degrees‐of‐freedom is obtained after eliminating the internal displacements by static condensation. The formulation of this element is new in that an integration technique is developed and applied to the element stiffness matrix and load vector. This technique is based on performing all the necessary integrations externally (i.e. outside the main computer program) and then modifying the formulation of the element matrices to account for this change. Hence, such a method allows the inclusion of higher‐order integration rules without any loss of economy, due to computer time, in the main program. Results using this element showed good agreement with other finite element and closed form solutions.

Estimating the parameters of a low frequency sinusoid with noise and harmonic distortion

Abstract: A digital method is presented for measuring the amplitude and frequency of low frequency sinusoidal signals. Theoretical and simulation results show that the proposed method is robust when the sinusoid is contaminated with noise. Moreover, the method can be adapted to eliminate the effect of harmonic distortion.

Sulfate resistance of jordanian cements as evaluated by different methods

Abstract: The relative sulfate resistance of cements available in Jordan are evaluated using different test methods. The cements included a pozzolanic portland with about 15% natural pozzolan addition, two ordinary portland cements, a sulfate resisting portland and a white cement. The test methods involved storing cubic, briquette and prismatic mortar specimens in the Dead Sea and Red Sea waters, in sodium and magnesium sulfate solutions and studying their deterioration through visual observations, ultrasonic pulse velocity measurements and relative strength determinations. The visual deterioration index concept used to follow the condition of the test specimens was found to be very useful. ASTM C 452 and C 1012 test methods were also applied. According to the results the pozzolanic portland along with the sulfate resisting cement performed better than the others. However, the behavior of the sulfate resisting cement in Dead Sea water was not satisfactory.

Effect of Magnetic Anisotropy on a One - Dimensional System of Magnetic Particles

Abstract: Using a statistical approach, the magnetization and the initial susceptibility for a one dimensional chain of a dilute ferromagnetic fluid have been investigated. Our assembly consisted of an N particle chain with N/3 non - interacting systems.

Fast measurement of telephone channel phase characteristics. Part 2: Method analysis

Abstract: A fast algorithm for measuring the frequency shift and phase jitter of telephone data channels which uses simple methods for extracting and processing the phase information of a received test signal was described in Part 1. A detailed analysis is now carried out for the Hilbert transformer and phase filter. The Hilbert transformer requires only one delay element, and two additions for each signal sample, and is thus attractive for general phase extraction applications with sinusoidal signals.

Fast measurement of telephone channel phase characteristics. Part 1: Method description

Abstract: A procedure for measuring the frequency shift and phase jitter of telephone data channels in the voice frequency band (300-3400 Hz) is presented. Rather than processing a received signal to obtain the required measurements, the phase is extracted and processed by a `phase filter'. An implementation of the phase filter is described which utilises power-2 coefficients to avoid the need for multiplication. This procedure is based on modern signal processing techniques which allow both simple and fast operation when implemented using a microprocessor. The technique can thus be easily incorporated into a telephone line measuring equipment or communication network monitoring system. Simulation results are given showing the effect of noise on the accuracy of the proposed algorithm, and some methods for the reduction of noise are also described. The trade-offs between the test signal duration and measurement accuracy are also considered.